Quantum Monte Carlo calculations of neutron matter with chiral three-body forces
Tews, I.; Gandolfi, Stefano; Gezerlis, A.; ...
2016-02-02
Chiral effective field theory (EFT) enables a systematic description of low-energy hadronic interactions with controlled theoretical uncertainties. For strongly interacting systems, quantum Monte Carlo (QMC) methods provide some of the most accurate solutions, but they require as input local potentials. We have recently constructed local chiral nucleon-nucleon (NN) interactions up to next-to-next-to-leading order (N 2LO). Chiral EFT naturally predicts consistent many-body forces. In this paper, we consider the leading chiral three-nucleon (3N) interactions in local form. These are included in auxiliary field diffusion Monte Carlo (AFDMC) simulations. We present results for the equation of state of neutron matter and formore » the energies and radii of neutron drops. Specifically, we study the regulator dependence at the Hartree-Fock level and in AFDMC and find that present local regulators lead to less repulsion from 3N forces compared to the usual nonlocal regulators.« less
$$\\chi$$EFT studies of few-nucleon systems: a status report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schiavilla, Rocco
2016-06-01
A status report onmore » $$\\chi$$EFT studies of few-nucleon electroweak structure and dynamics is provided, including electromagnetic elastic form factors of few-nucleon systems, the $pp$ weak fusion and muon weak captures on deuteron and $^3$He, and a number of parity-violating processes induced by hadronic weak interactions.« less
Symbolic computation of the Hartree-Fock energy from a chiral EFT three-nucleon interaction at N 2LO
NASA Astrophysics Data System (ADS)
Gebremariam, B.; Bogner, S. K.; Duguet, T.
2010-06-01
We present the first of a two-part Mathematica notebook collection that implements a symbolic approach for the application of the density matrix expansion (DME) to the Hartree-Fock (HF) energy from a chiral effective field theory (EFT) three-nucleon interaction at N 2LO. The final output from the notebooks is a Skyrme-like energy density functional that provides a quasi-local approximation to the non-local HF energy. In this paper, we discuss the derivation of the HF energy and its simplification in terms of the scalar/vector-isoscalar/isovector parts of the one-body density matrix. Furthermore, a set of steps is described and illustrated on how to extend the approach to other three-nucleon interactions. Program summaryProgram title: SymbHFNNN Catalogue identifier: AEGC_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEGC_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 96 666 No. of bytes in distributed program, including test data, etc.: 378 083 Distribution format: tar.gz Programming language: Mathematica 7.1 Computer: Any computer running Mathematica 6.0 and later versions Operating system: Windows Xp, Linux/Unix RAM: 256 Mb Classification: 5, 17.16, 17.22 Nature of problem: The calculation of the HF energy from the chiral EFT three-nucleon interaction at N 2LO involves tremendous spin-isospin algebra. The problem is compounded by the need to eventually obtain a quasi-local approximation to the HF energy, which requires the HF energy to be expressed in terms of scalar/vector-isoscalar/isovector parts of the one-body density matrix. The Mathematica notebooks discussed in this paper solve the latter issue. Solution method: The HF energy from the chiral EFT three-nucleon interaction at N 2LO is cast into a form suitable for an automatic simplification of the spin-isospin traces. Several Mathematica functions and symbolic manipulation techniques are used to obtain the result in terms of the scalar/vector-isoscalar/isovector parts of the one-body density matrix. Running time: Several hours
Chiral symmetry and the nucleon-nucleon interaction
Machleidt, Ruprecht
2016-04-20
We review how nuclear forces emerge from low-energy quantum chromodynamics (QCD) via chiral effective field theory (EFT). During the past two decades, this approach has evolved into a powerful tool to derive nuclear two- and many-body forces in a systematic and model-independent way. We then focus on the nucleon-nucleon (NN) interaction and show in detail how, governed by chiral symmetry, the long- and intermediate-range of the NN potential builds up order by order. We proceed up to sixth order in small momenta, where convergence is achieved. Lastly, the final result allows for a full assessment of the validity of themore » chiral EFT approach to the NN interaction.« less
Bayesian Methods for Effective Field Theories
NASA Astrophysics Data System (ADS)
Wesolowski, Sarah
Microscopic predictions of the properties of atomic nuclei have reached a high level of precision in the past decade. This progress mandates improved uncertainty quantification (UQ) for a robust comparison of experiment with theory. With the uncertainty from many-body methods under control, calculations are now sensitive to the input inter-nucleon interactions. These interactions include parameters that must be fit to experiment, inducing both uncertainty from the fit and from missing physics in the operator structure of the Hamiltonian. Furthermore, the implementation of the inter-nucleon interactions is not unique, which presents the additional problem of assessing results using different interactions. Effective field theories (EFTs) take advantage of a separation of high- and low-energy scales in the problem to form a power-counting scheme that allows the organization of terms in the Hamiltonian based on their expected contribution to observable predictions. This scheme gives a natural framework for quantification of uncertainty due to missing physics. The free parameters of the EFT, called the low-energy constants (LECs), must be fit to data, but in a properly constructed EFT these constants will be natural-sized, i.e., of order unity. The constraints provided by the EFT, namely the size of the systematic uncertainty from truncation of the theory and the natural size of the LECs, are assumed information even before a calculation is performed or a fit is done. Bayesian statistical methods provide a framework for treating uncertainties that naturally incorporates prior information as well as putting stochastic and systematic uncertainties on an equal footing. For EFT UQ Bayesian methods allow the relevant EFT properties to be incorporated quantitatively as prior probability distribution functions (pdfs). Following the logic of probability theory, observable quantities and underlying physical parameters such as the EFT breakdown scale may be expressed as pdfs that incorporate the prior pdfs. Problems of model selection, such as distinguishing between competing EFT implementations, are also natural in a Bayesian framework. In this thesis we focus on two complementary topics for EFT UQ using Bayesian methods--quantifying EFT truncation uncertainty and parameter estimation for LECs. Using the order-by-order calculations and underlying EFT constraints as prior information, we show how to estimate EFT truncation uncertainties. We then apply the result to calculating truncation uncertainties on predictions of nucleon-nucleon scattering in chiral effective field theory. We apply model-checking diagnostics to our calculations to ensure that the statistical model of truncation uncertainty produces consistent results. A framework for EFT parameter estimation based on EFT convergence properties and naturalness is developed which includes a series of diagnostics to ensure the extraction of the maximum amount of available information from data to estimate LECs with minimal bias. We develop this framework using model EFTs and apply it to the problem of extrapolating lattice quantum chromodynamics results for the nucleon mass. We then apply aspects of the parameter estimation framework to perform case studies in chiral EFT parameter estimation, investigating a possible operator redundancy at fourth order in the chiral expansion and the appropriate inclusion of truncation uncertainty in estimating LECs.
Chiral effective theory methods and their application to the structure of hadrons from lattice QCD
NASA Astrophysics Data System (ADS)
Shanahan, P. E.
2016-12-01
For many years chiral effective theory (ChEFT) has enabled and supported lattice QCD calculations of hadron observables by allowing systematic effects from unphysical lattice parameters to be controlled. In the modern era of precision lattice simulations approaching the physical point, ChEFT techniques remain valuable tools. In this review we discuss the modern uses of ChEFT applied to lattice studies of hadron structure in the context of recent determinations of important and topical quantities. We consider muon g-2, strangeness in the nucleon, the proton radius, nucleon polarizabilities, and sigma terms relevant to the prediction of dark-matter-hadron interaction cross-sections, among others.
Uncertainty Analysis and Order-by-Order Optimization of Chiral Nuclear Interactions
Carlsson, Boris; Forssen, Christian; Fahlin Strömberg, D.; ...
2016-02-24
Chiral effective field theory ( ΧEFT) provides a systematic approach to describe low-energy nuclear forces. Moreover, EFT is able to provide well-founded estimates of statistical and systematic uncertainties | although this unique advantage has not yet been fully exploited. We ll this gap by performing an optimization and statistical analysis of all the low-energy constants (LECs) up to next-to-next-to-leading order. Our optimization protocol corresponds to a simultaneous t to scattering and bound-state observables in the pion-nucleon, nucleon-nucleon, and few-nucleon sectors, thereby utilizing the full model capabilities of EFT. Finally, we study the effect on other observables by demonstrating forward-error-propagation methodsmore » that can easily be adopted by future works. We employ mathematical optimization and implement automatic differentiation to attain e cient and machine-precise first- and second-order derivatives of the objective function with respect to the LECs. This is also vital for the regression analysis. We use power-counting arguments to estimate the systematic uncertainty that is inherent to EFT and we construct chiral interactions at different orders with quantified uncertainties. Statistical error propagation is compared with Monte Carlo sampling showing that statistical errors are in general small compared to systematic ones. In conclusion, we find that a simultaneous t to different sets of data is critical to (i) identify the optimal set of LECs, (ii) capture all relevant correlations, (iii) reduce the statistical uncertainty, and (iv) attain order-by-order convergence in EFT. Furthermore, certain systematic uncertainties in the few-nucleon sector are shown to get substantially magnified in the many-body sector; in particlar when varying the cutoff in the chiral potentials. The methodology and results presented in this Paper open a new frontier for uncertainty quantification in ab initio nuclear theory.« less
Effective field theory description of halo nuclei
NASA Astrophysics Data System (ADS)
Hammer, H.-W.; Ji, C.; Phillips, D. R.
2017-10-01
Nuclear halos emerge as new degrees of freedom near the neutron and proton driplines. They consist of a core and one or a few nucleons which spend most of their time in the classically-forbidden region outside the range of the interaction. Individual nucleons inside the core are thus unresolved in the halo configuration, and the low-energy effective interactions are short-range forces between the core and the valence nucleons. Similar phenomena occur in clusters of 4He atoms, cold atomic gases near a Feshbach resonance, and some exotic hadrons. In these weakly-bound quantum systems universal scaling laws for s-wave binding emerge that are independent of the details of the interaction. Effective field theory (EFT) exposes these correlations and permits the calculation of non-universal corrections to them due to short-distance effects, as well as the extension of these ideas to systems involving the Coulomb interaction and/or binding in higher angular-momentum channels. Halo nuclei exhibit all these features. Halo EFT, the EFT for halo nuclei, has been used to compute the properties of single-neutron, two-neutron, and single-proton halos of s-wave and p-wave type. This review summarizes these results for halo binding energies, radii, Coulomb dissociation, and radiative capture, as well as the connection of these properties to scattering parameters, thereby elucidating the universal correlations between all these observables. We also discuss how Halo EFT's encoding of the long-distance physics of halo nuclei can be used to check and extend ab initio calculations that include detailed modeling of their short-distance dynamics.
The scalar and electromagnetic form factors of the nucleon in dispersively improved Chiral EFT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alarcon, Jose Manuel
We present a method for calculating the nucleon form factors of G-parity-even operators. This method combines chiral effective field theory (χEFT) and dispersion theory. Through unitarity we factorize the imaginary part of the form factors into a perturbative part, calculable with χEFT, and a non-perturbative part, obtained through other methods. We consider the scalar and electromagnetic (EM) form factors of the nucleon. The results show an important improvement compared to standard chiral calculations, and can be used in analysis of the low-energy properties of the nucleon.
Dark matter effective field theory scattering in direct detection experiments
Schneck, K.
2015-05-01
We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implicationsmore » of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.« less
Dark matter effective field theory scattering in direct detection experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneck, K.; Cabrera, B.; Cerdeño, D. G.
2015-05-18
We examine the consequences of the effective field theory (EFT) of dark matter-nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. Here. we demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. In conclusion, we discussmore » the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.« less
Dark matter effective field theory scattering in direct detection experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneck, K.; Cabrera, B.; Cerdeño, D. G.
2015-05-18
We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implicationsmore » of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.« less
Light-front representation of chiral dynamics with Δ isobar and large-N c relations
Granados, C.; Weiss, C.
2016-06-13
Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O(M π –1) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). Recent work has shown that the EFT results can be represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition of the nucleon to soft-pion-nucleon intermediate states, resulting in a quantum-mechanical picture of the peripheral transverse densities. We now extend this representation to include intermediate states with Δ isobars and implement relations basedmore » on the large-N c limit of QCD. We derive the wave function overlap formulas for the Δ contributions to the peripheral transverse densities by way of a three-dimensional reduction of relativistic chiral EFT expressions. Our procedure effectively maintains rotational invariance and avoids the ambiguities with higher-spin particles in the light-front time-ordered approach. We study the interplay of πN and πΔ intermediate states in the quantum-mechanical picture of the densities in a transversely polarized nucleon. We show that the correct N c-scaling of the charge and magnetization densities emerges as the result of the particular combination of currents generated by intermediate states with degenerate N and Δ. The off-shell behavior of the chiral EFT is summarized in contact terms and can be studied easily. As a result, the methods developed here can be applied to other peripheral densities and to moments of the nucleon's generalized parton distributions.« less
Study of the Hyperon-Nucleon Interaction in Exclusive Λ Photoproduction off the Deuteron
NASA Astrophysics Data System (ADS)
Zachariou, Nicholas; CLAS Collaboration
2014-09-01
Understanding the nature of the nuclear force in terms of the fundamental degrees of freedom of the theory of strong interaction, Quantum Chromodynamics (QCD), is one of the primary goals of modern nuclear physics. While the nucleon-nucleon (NN) interaction has been studied for decades, a systematic description of the NN potential has been achieved only recently with the development of low-energy Effective Field Theories (EFT). To obtain a comprehensive understanding of the strong interaction, dynamics involving strange baryons must be studied. Currently, little is known about the properties of the hyperon-nucleon (YN) and the hyperon-hyperon (YY) interactions. In this talk I will describe our current research of the Λn interaction using the E06-103 experiment performed with the CLAS detector in Hall B at Jefferson Lab. The large kinematic coverage of the CLAS combined with the exceptionally high quality of the experimental data allows to identify and select final-state interaction events in the reaction γd -->K+ Λn and to establish their kinematical dependencies. The large set of observables we aim to obtain will provide tight constraints on modern YN potentials. I will present the current status of the project and will discuss future incentives. Understanding the nature of the nuclear force in terms of the fundamental degrees of freedom of the theory of strong interaction, Quantum Chromodynamics (QCD), is one of the primary goals of modern nuclear physics. While the nucleon-nucleon (NN) interaction has been studied for decades, a systematic description of the NN potential has been achieved only recently with the development of low-energy Effective Field Theories (EFT). To obtain a comprehensive understanding of the strong interaction, dynamics involving strange baryons must be studied. Currently, little is known about the properties of the hyperon-nucleon (YN) and the hyperon-hyperon (YY) interactions. In this talk I will describe our current research of the Λn interaction using the E06-103 experiment performed with the CLAS detector in Hall B at Jefferson Lab. The large kinematic coverage of the CLAS combined with the exceptionally high quality of the experimental data allows to identify and select final-state interaction events in the reaction γd -->K+ Λn and to establish their kinematical dependencies. The large set of observables we aim to obtain will provide tight constraints on modern YN potentials. I will present the current status of the project and will discuss future incentives. for the CLAS Collaboration.
Tritium β decay in chiral effective field theory
Baroni, A.; Girlanda, L.; Kievsky, A.; ...
2016-08-18
We evaluate the Fermi and Gamow-Teller (GT) matrix elements in tritiummore » $$\\beta$$-decay by including in the charge-changing weak current the corrections up to one loop recently derived in nuclear chiral effective field theory ($$\\chi$$ EFT). The trinucleon wave functions are obtained from hyperspherical-harmonics solutions of the Schroedinger equation with two- and three-nucleon potentials corresponding to either $$\\chi$$ EFT (the N3LO/N2LO combination) or meson-exchange phenomenology (the AV18/UIX combination). We find that contributions due to loop corrections in the axial current are, in relative terms, as large as (and in some cases, dominate) those from one-pion exchange, which nominally occur at lower order in the power counting. Furthermore, we also provide values for the low-energy constants multiplying the contact axial current and three-nucleon potential, required to reproduce the experimental GT matrix element and trinucleon binding energies in the N3LO/N2LO and AV18/UIX calculations.« less
NASA Astrophysics Data System (ADS)
Barnea, N.; Bazak, B.; Friedman, E.; Gal, A.
2017-12-01
A three-body force acting between the η-meson and two nucleons was overlooked inadvertently in the model description and discussion in the published version of our paper "Onset of η-nuclear binding in a pionless EFT approach" [Phys. Lett. B 771 (2017) 297-302] while present in the actual numerical calculations. The stated conclusion that a stabilizing ηNN contact term was not needed is therefore incorrect. Such a three-body force, associated with a new low energy constant dηNNΛ, must be introduced at leading order to stabilize η-nucleus systems.
Chiral EFT based nuclear forces: achievements and challenges
NASA Astrophysics Data System (ADS)
Machleidt, R.; Sammarruca, F.
2016-08-01
During the past two decades, chiral effective field theory has become a popular tool to derive nuclear forces from first principles. Two-nucleon interactions have been worked out up to sixth order of chiral perturbation theory and three-nucleon forces up to fifth order. Applications of some of these forces have been conducted in nuclear few- and many-body systems—with a certain degree of success. But in spite of these achievements, we are still faced with great challenges. Among them is the issue of a proper uncertainty quantification of predictions obtained when applying these forces in ab initio calculations of nuclear structure and reactions. A related problem is the order by order convergence of the chiral expansion. We start this review with a pedagogical introduction and then present the current status of the field of chiral nuclear forces. This is followed by a discussion of representative examples for the application of chiral two- and three-body forces in the nuclear many-body system including convergence issues.
The parity-violating asymmetry in the 3He(n,p)3H reaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
M. Viviani, R. Schiavilla, L. Girlanda, A. Kievsky, L.E. Marcucci
2010-10-01
The longitudinal asymmetry induced by parity-violating (PV) components in the nucleon-nucleon potential is studied in the charge-exchange reaction 3He(n,p)3H at vanishing incident neutron energies. An expression for the PV observable is derived in terms of T-matrix elements for transitions from the {2S+1}L_J=1S_0 and 3S_1 states in the incoming n-3He channel to states with J=0 and 1 in the outgoing p-3H channel. The T-matrix elements involving PV transitions are obtained in first-order perturbation theory in the hadronic weak-interaction potential, while those connecting states of the same parity are derived from solutions of the strong-interaction Hamiltonian with the hyperspherical-harmonics method. The coupled-channelmore » nature of the scattering problem is fully accounted for. Results are obtained corresponding to realistic or chiral two- and three-nucleon strong-interaction potentials in combination with either the DDH or pionless EFT model for the weak-interaction potential. The asymmetries, predicted with PV pion and vector-meson coupling constants corresponding (essentially) to the DDH "best values" set, range from -9.44 to -2.48 in units of 10^{-8}, depending on the input strong-interaction Hamiltonian. This large model dependence is a consequence of cancellations between long-range (pion) and short-range (vector-meson) contributions, and is of course sensitive to the assumed values for the PV coupling constants.« less
Nucleon form factors in dispersively improved chiral effective field theory: Scalar form factor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alarcon Soriano, Jose Manuel; Weiss, Christian
We propose a method for calculating the nucleon form factors (FFs) ofmore » $G$-parity-even operators by combining Chiral Effective Field Theory ($$\\chi$$EFT) and dispersion analysis. The FFs are expressed as dispersive integrals over the two-pion cut at $$t > 4 M_\\pi^2$$. The spectral functions are obtained from the elastic unitarity condition and expressed as products of the complex $$\\pi\\pi \\rightarrow N\\bar N$$ partial-wave amplitudes and the timelike pion FF. $$\\chi$$EFT is used to calculate the ratio of the partial-wave amplitudes and the pion FF, which is real and free of $$\\pi\\pi$$ rescattering in the $t$-channel ($N/D$ method). The rescattering effects are then incorporated by multiplying with the squared modulus of the empirical pion FF. The procedure results in a marked improvement compared to conventional $$\\chi$$EFT calculations of the spectral functions. We apply the method to the nucleon scalar FF and compute the scalar spectral function, the scalar radius, the $t$-dependent FF, and the Cheng-Dashen discrepancy. Higher-order chiral corrections are estimated through the $$\\pi N$$ low-energy constants. Results are in excellent agreement with dispersion-theoretical calculations. We elaborate several other interesting aspects of our method. The results show proper scaling behavior in the large-$$N_c$$ limit of QCD because the $$\\chi$$EFT includes $N$ and $$\\Delta$$ intermediate states. The squared modulus of the timelike pion FF required by our method can be extracted from Lattice QCD calculations of vacuum correlation functions of the operator at large Euclidean distances. Our method can be applied to the nucleon FFs of other operators of interest, such as the isovector-vector current, the energy-momentum tensor, and twist-2 QCD operators (moments of generalized parton distributions).« less
Nucleon form factors in dispersively improved chiral effective field theory: Scalar form factor
Alarcon Soriano, Jose Manuel; Weiss, Christian
2017-11-20
We propose a method for calculating the nucleon form factors (FFs) ofmore » $G$-parity-even operators by combining Chiral Effective Field Theory ($$\\chi$$EFT) and dispersion analysis. The FFs are expressed as dispersive integrals over the two-pion cut at $$t > 4 M_\\pi^2$$. The spectral functions are obtained from the elastic unitarity condition and expressed as products of the complex $$\\pi\\pi \\rightarrow N\\bar N$$ partial-wave amplitudes and the timelike pion FF. $$\\chi$$EFT is used to calculate the ratio of the partial-wave amplitudes and the pion FF, which is real and free of $$\\pi\\pi$$ rescattering in the $t$-channel ($N/D$ method). The rescattering effects are then incorporated by multiplying with the squared modulus of the empirical pion FF. The procedure results in a marked improvement compared to conventional $$\\chi$$EFT calculations of the spectral functions. We apply the method to the nucleon scalar FF and compute the scalar spectral function, the scalar radius, the $t$-dependent FF, and the Cheng-Dashen discrepancy. Higher-order chiral corrections are estimated through the $$\\pi N$$ low-energy constants. Results are in excellent agreement with dispersion-theoretical calculations. We elaborate several other interesting aspects of our method. The results show proper scaling behavior in the large-$$N_c$$ limit of QCD because the $$\\chi$$EFT includes $N$ and $$\\Delta$$ intermediate states. The squared modulus of the timelike pion FF required by our method can be extracted from Lattice QCD calculations of vacuum correlation functions of the operator at large Euclidean distances. Our method can be applied to the nucleon FFs of other operators of interest, such as the isovector-vector current, the energy-momentum tensor, and twist-2 QCD operators (moments of generalized parton distributions).« less
Ab initio description of continuum effects in A=11 exotic systems with chiral NN+3N forces
NASA Astrophysics Data System (ADS)
Calci, Angelo; Navratil, Petr; Roth, Robert; Dohet-Eraly, Jeremy; Quaglioni, Sofia; Hupin, Guillaume
2016-09-01
Based on the fundamental symmetries of QCD, chiral effective field theory (EFT) provides two- (NN), three- (3N) and many-nucleon interactions in a consistent and systematically improvable scheme. The rapid developments to construct divers families of chiral NN+3N interactions and the conceptual and technical improvements of ab initio many-body approaches pose a great opportunity for nuclear physics. By studying particular interesting phenomena in nuclear structure and reaction observables one can discriminate between different forces and study the predictive power of chiral EFT. The accurate description of the 11Be nucleus, in particular, the ground-state parity inversion and exceptionally strong E1 transition between its two bound states constitute an enormous challenge for the developments of nuclear forces and many-body approaches. We present a sensitivity analysis of structure and reaction observables to different NN+3N interactions in 11Be and n+10Be as well as the mirror p+10C scattering using the ab initio NCSM with continuum (NCSMC). Supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Work Proposal No. SCW1158. TRIUMF receives federal funding via a contribution agreement with the National Research Council of Canada.
Light-front representation of chiral dynamics in peripheral transverse densities
Granados, Carlos G.; Weiss, Christian
2015-07-31
The nucleon's electromagnetic form factors are expressed in terms of the transverse densities of charge and magnetization at fixed light-front time. At peripheral transverse distances b = O(M_pi^{-1}) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). We represent the leading-order chiral EFT results for the peripheral transverse densities as overlap integrals of chiral light-front wave functions, describing the transition of the initial nucleon to soft pion-nucleon intermediate states and back. The new representation (a) explains the parametric order of the peripheral transverse densities; (b) establishes an inequality between the spin-independentmore » and -dependent densities; (c) exposes the role of pion orbital angular momentum in chiral dynamics; (d) reveals a large left-right asymmetry of the current in a transversely polarized nucleon and suggests a simple interpretation. The light-front representation enables a first-quantized, quantum-mechanical view of chiral dynamics that is fully relativistic and exactly equivalent to the second-quantized, field-theoretical formulation. It relates the charge and magnetization densities measured in low-energy elastic scattering to the generalized parton distributions probed in peripheral high-energy scattering processes. The method can be applied to nucleon form factors of other operators, e.g. the energy-momentum tensor.« less
Nucleon Polarisabilities and Effective Field Theories
NASA Astrophysics Data System (ADS)
Griesshammer, Harald W.
2017-09-01
Low-energy Compton scattering probes the nucleon's two-photon response to electric and magnetic fields at fixed photon frequency and multipolarity. It tests the symmetries and strengths of the interactions between constituents, and with photons. For convenience, this energy-dependent information is often compressed into the two scalar dipole polarisabilities αE 1 and βM 1 at zero photon energy. These are fundamental quantities, and important for the proton charge radius puzzle and the Lamb shift of muonic hydrogen. Combined with emerging lattice QCD computations, they provide stringent tests for our understanding of hadron structure. Extractions of the proton and neutron polarisabilities from all published elastic data below 300 MeV in Chiral Effective Field Theory with explicit Δ (1232) are now available. This talk emphasises χEFT as natural bridge between lattice QCD and ongoing or approved efforts at HI γS, MAMI and MAX-lab. Chiral lattice extrapolations from mπ > 200 MeV to the physical point compare well to lattice computations. Combining χEFT with high-intensity experiments with polarised targets and polarised beams will extract not only scalar polarisabilities, but in particular the four so-far poorly explored spin-polarisabilities. These parametrise the stiffness of the spin in external electro-magnetic fields (nucleonic bi-refringence/Faraday effect). New chiral predictions for proton, deuteron and 3He observables show intriguing sensitivities on spin and neutron polarisabilities. Data consistency and a model-independent quantification of residual theory uncertainties by Bayesian analysis are also discussed. Proton-neutron differences explore the interplay between chiral symmetry breaking and short-distance Physics. Finally, I address their impact on the neutron-proton mass difference, big-bang nucleosynthesis, and their relevance for anthropic arguments. Supported in part by DOE DE-SC0015393 and George Washington University.
Properties of infrared extrapolations in a harmonic oscillator basis
Coon, Sidney A.; Kruse, Michael K. G.
2016-02-22
Here, the success and utility of effective field theory (EFT) in explaining the structure and reactions of few-nucleon systems has prompted the initiation of EFT-inspired extrapolations to larger model spaces in ab initio methods such as the no-core shell model (NCSM). In this contribution, we review and continue our studies of infrared (ir) and ultraviolet (uv) regulators of NCSM calculations in which the input is phenomenological NN and NNN interactions fitted to data. We extend our previous findings that an extrapolation in the ir cutoff with the uv cutoff above the intrinsic uv scale of the interaction is quite successful,more » not only for the eigenstates of the Hamiltonian but also for expectation values of operators, such as r 2, considered long range. The latter results are obtained with Hamiltonians transformed by the similarity renormalization group (SRG) evolution. On the other hand, a possible extrapolation of ground state energies in the uv cutoff when the ir cutoff is below the intrinsic ir scale is not robust and does not agree with the ir extrapolation of the same data or with independent calculations using other methods.« less
Fundamental Neutron Physics: Theory and Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gudkov, Vladimir
The goal of the proposal was to study the possibility of searching for manifestations of new physics beyond the Standard model in fundamental neutron physics experiments. This involves detailed theoretical analyses of parity- and time reversal invariance-violating processes in neutron-induced reactions, properties of neutron β-decay, and the precise description of properties of neutron interactions with nuclei. To describe neutron-nuclear interactions, we use both the effective field theory approach and the theory of nuclear reaction with phenomenological nucleon potentials for the systematic description of parity- and time reversal-violating effects in the consistent way. A major emphasis of our research during themore » funding period has been the study of parity violation (PV) and time reversal invariance violation (TRIV) in few-body systems. We studied PV effects in non-elastic processes in three-nucleon system using both ”DDH-like” and effective field theory (EFT) approaches. The wave functions were obtained by solving three-body Faddeev equations in configuration space for a number of realistic strong potentials. The observed model dependence for the DDH approach indicates intrinsic difficulty in the description of nuclear PV effects, and it could be the reason for the observed discrepancies in the nuclear PV data analysis. It shows that the DDH approach could be a reasonable approach for analysis of PV effects only if exactly the same strong and weak potentials are used in calculating all PV observables in all nuclei. However, the existing calculations of nuclear PV effects were performed using different potentials; therefore, strictly speaking, one cannot compare the existing results of these calculations among themselves.« less
Electromagnetic structure of few-nucleon ground states
Marcucci, Laura E.; Gross, Franz L.; Peña, M. T.; ...
2016-01-08
Experimental form factors of the hydrogen and helium isotopes, extracted from an up-to-date global analysis of cross sections and polarization observables measured in elastic electron scattering from these systems, are compared to predictions obtained in three different theoretical approaches: the first is based on realistic interactions and currents, including relativistic corrections (labeled as the conventional approach); the second relies on a chiral effective field theory description of the strong and electromagnetic interactions in nuclei (labeled ChiEFT); the third utilizes a fully relativistic treatment of nuclear dynamics as implemented in the covariant spectator theory (labeled CST). Furthermore, for momentum transfers belowmore » Q < 5 fm -1 there is satisfactory agreement between experimental data and theoretical results in all three approaches. Conversely, at Q > 5 fm -1, particularly in the case of the deuteron, a relativistic treatment of the dynamics, as is done in the CST, is necessary. The experimental data on the deuteron A structure function extend to Q ~ 12 fm -1, and the close agreement between these data and the CST results suggests that, even in this extreme kinematical regime, there is no evidence for new effects coming from quark and gluon degrees of freedom at short distances.« less
NASA Astrophysics Data System (ADS)
Ormand, Erich; Brown, Alex; Hjorth-Jensen, Morten
2017-09-01
We present calculations for the c-coefficients of the isobaric mass multiplet equation for nuclei from A = 42 to A = 54 based on two-body effective interactions derived from three realistic nucleon-nucleon interactions: CD-Bonn, N3LO, and Argonne V18. The two-body effective interactions were derived using G-matrix or Vlowk augmented by perturbation theory extended to third order. We demonstrate a clear dependence in the c-coefficients on the short-ranged charge-symmetry breaking (CSB) part of the strong interaction, which is required to reproduce their overall behavior as a function of excitation (angular momentum). We find, however, that the CSB component in all three realistic nucleon-nucleon interactions is too large when compared to experiment, and that, furthermore, there is significant disagreement between each of the three interactions. This implies either: 1) a deficiency in our understanding of isospin-symmetry breaking in the nucleon-nucleon interaction, 2) significant isospin-symmetry breaking in the initial three-nucleon interaction, or 3) large contributions to isospin-symmetry breaking in three-nucleon interactions induced by the renormalization procedure. This work performed for the U.S. DOE by LLNL under Contract DE-AC52-07NA27344. WEO: DOE/NP FWP SCW0498. BAB: NSF Grant No. PHY-1404442. MHJ: NSF Grant No. PHY-1404159 and the Research Council of Norway contract ISP-Fysikk/216699.
Onset of η-nuclear binding in a pionless EFT approach
NASA Astrophysics Data System (ADS)
Barnea, N.; Bazak, B.; Friedman, E.; Gal, A.
2017-08-01
ηNNN and ηNNNN bound states are explored in stochastic variational method (SVM) calculations within a pionless effective field theory (EFT) approach at leading order. The theoretical input consists of regulated NN and NNN contact terms, and a regulated energy dependent ηN contact term derived from coupled-channel models of the N* (1535) nucleon resonance. A self consistency procedure is applied to deal with the energy dependence of the ηN subthreshold input, resulting in a weak dependence of the calculated η-nuclear binding energies on the EFT regulator. It is found, in terms of the ηN scattering length aηN, that the onset of binding η 3He requires a minimal value of ReaηN close to 1 fm, yielding then a few MeV η binding in η 4He. The onset of binding η 4He requires a lower value of ReaηN, but exceeding 0.7 fm.
Lynn, J. E.; Tews, I.; Carlson, J.; ...
2017-11-30
Local chiral effective field theory interactions have recently been developed and used in the context of quantum Monte Carlo few- and many-body methods for nuclear physics. In this paper, we go over detailed features of local chiral nucleon-nucleon interactions and examine their effect on properties of the deuteron, paying special attention to the perturbativeness of the expansion. We then turn to three-nucleon interactions, focusing on operator ambiguities and their interplay with regulator effects. We then discuss the nuclear Green's function Monte Carlo method, going over both wave-function correlations and approximations for the two- and three-body propagators. Finally, following this, wemore » present a range of results on light nuclei: Binding energies and distribution functions are contrasted and compared, starting from several different microscopic interactions.« less
Chiral effective-field theory of the nucleon spin structure
NASA Astrophysics Data System (ADS)
Pascalutsa, Vladimir
2017-01-01
I will review the recent chiral EFT calculations of the nucleon (spin) structure functions at low Q2, confronted with the Jefferson Lab measurements. The moments of the structure functions correspond with various polarizabilities, and I will explain why one of them - δLT - is especially interesting. I will also discuss how the spin structure functions at low Q enter in the atomic calculations of the hyperfine splittings and how they are impacting the ongoing experimental program at PSI (Switzerland) to measure the ground-state hyperfine splitting of muonic hydrogen. Partially supported by the Deutsche Forschungsgemeinschaft (DFG) through the Collaborative Research Center SFB 1044 [The Low-Energy Frontier of the Standard Model].
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alarcon, J. M.; Weiss, C.
We study the nucleon electromagnetic form factors (EM FFs) using a recently developed method combining Chiral Effective Field Theory (more » $$\\chi$$EFT) and dispersion analysis. The spectral functions on the two-pion cut at $$t > 4 M_\\pi^2$$ are constructed using the elastic unitarity relation and an $N/D$ representation. $$\\chi$$EFT is used to calculate the real unctions $$J_\\pm^1 (t) = f_\\pm^1(t)/F_\\pi(t)$$ (ratios of the complex $$\\pi\\pi \\rightarrow N \\bar N$$ partial-wave amplitudes and the timelike pion FF), which are free of $$\\pi\\pi$$ rescattering. Rescattering effects are included through the empirical timelike pion FF $$|F_\\pi(t)|^2$$. The method allows us to compute the isovector EM spectral functions up to $$t \\sim 1$$ GeV$^2$ with controlled accuracy (LO, NLO, and partial N2LO). With the spectral functions we calculate the isovector nucleon EM FFs and their derivatives at $t = 0$ (EM radii, moments) using subtracted dispersion relations. We predict the values of higher FF derivatives with minimal uncertainties and explain their collective behavior. Finally, we estimate the individual proton and neutron FFs by adding an empirical parametrization of the isoscalar sector. Excellent agreement with the present low-$Q^2$ FF data is achieved up to $$\\sim$$0.5 GeV$^2$ for $$G_E$$, and up to $$\\sim$$0.2 GeV$^2$ for $$G_M$$. Our results can be used to guide the analysis of low-$Q^2$ elastic scattering data and the extraction of the proton charge radius.« less
Alarcon, J. M.; Weiss, C.
2018-05-08
We study the nucleon electromagnetic form factors (EM FFs) using a recently developed method combining Chiral Effective Field Theory (more » $$\\chi$$EFT) and dispersion analysis. The spectral functions on the two-pion cut at $$t > 4 M_\\pi^2$$ are constructed using the elastic unitarity relation and an $N/D$ representation. $$\\chi$$EFT is used to calculate the real unctions $$J_\\pm^1 (t) = f_\\pm^1(t)/F_\\pi(t)$$ (ratios of the complex $$\\pi\\pi \\rightarrow N \\bar N$$ partial-wave amplitudes and the timelike pion FF), which are free of $$\\pi\\pi$$ rescattering. Rescattering effects are included through the empirical timelike pion FF $$|F_\\pi(t)|^2$$. The method allows us to compute the isovector EM spectral functions up to $$t \\sim 1$$ GeV$^2$ with controlled accuracy (LO, NLO, and partial N2LO). With the spectral functions we calculate the isovector nucleon EM FFs and their derivatives at $t = 0$ (EM radii, moments) using subtracted dispersion relations. We predict the values of higher FF derivatives with minimal uncertainties and explain their collective behavior. Finally, we estimate the individual proton and neutron FFs by adding an empirical parametrization of the isoscalar sector. Excellent agreement with the present low-$Q^2$ FF data is achieved up to $$\\sim$$0.5 GeV$^2$ for $$G_E$$, and up to $$\\sim$$0.2 GeV$^2$ for $$G_M$$. Our results can be used to guide the analysis of low-$Q^2$ elastic scattering data and the extraction of the proton charge radius.« less
Few-Nucleon Research at TUNL: Probing Two- and Three-Nucleon Interactions with Neutrons
NASA Astrophysics Data System (ADS)
Howell, C. R.; Tornow, W.; Witała, H.
2016-03-01
The central goal of few-nucleon research at the Triangle Universities Nuclear Laboratory (TUNL) is to perform measurements that contribute to advancing ab-initio calculations of nuclear structure and reactions. The program aims include evaluating theoretical treatments of few-nucleon reaction dynamics through strategically comparing theory predictions to data, determining properties of the neutron-neutron interaction that are not accessible in two-nucleon reactions, and searching for evidence of longrange features of three-nucleon interactions, e.g., spin and isospin dependence. This paper will review studies of three- and four-nucleon systems at TUNL conducted using unpolarized and polarized neutron beams. Measurements of neutron-induced reactions performed by groups at TUNL over the last six years are described in comparison with theory predictions. The results are discussed in the context of the program goals stated above. Measurements of vector analyzing powers for elastic scattering in A=3 and A=4 systems, differential cross sections for neutron-deuteron elastic scattering and neutrondeuteron breakup in several final-state configurations are described. The findings from these studies and plans for the coming three years are presented in the context of worldwide activities in this front, in particular, research presented in this session.
A periodic table of effective field theories
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cheung, Clifford; Kampf, Karol; Novotny, Jiri
We systematically explore the space of scalar effective field theories (EFTs) consistent with a Lorentz invariant and local S-matrix. To do so we define an EFT classification based on four parameters characterizing 1) the number of derivatives per interaction, 2) the soft properties of amplitudes, 3) the leading valency of the interactions, and 4) the spacetime dimension. Carving out the allowed space of EFTs, we prove that exceptional EFTs like the non-linear sigma model, Dirac-Born-Infeld theory, and the special Galileon lie precisely on the boundary of allowed theory space. Using on-shell momentum shifts and recursion relations, we prove that EFTsmore » with arbitrarily soft behavior are forbidden and EFTs with leading valency much greater than the spacetime dimension cannot have enhanced soft behavior. We then enumerate all single scalar EFTs in d < 6 and verify that they correspond to known theories in the literature. Finally, our results suggest that the exceptional theories are the natural EFT analogs of gauge theory and gravity because they are one-parameter theories whose interactions are strictly dictated by properties of the S-matrix.« less
A periodic table of effective field theories
Cheung, Clifford; Kampf, Karol; Novotny, Jiri; ...
2017-02-06
We systematically explore the space of scalar effective field theories (EFTs) consistent with a Lorentz invariant and local S-matrix. To do so we define an EFT classification based on four parameters characterizing 1) the number of derivatives per interaction, 2) the soft properties of amplitudes, 3) the leading valency of the interactions, and 4) the spacetime dimension. Carving out the allowed space of EFTs, we prove that exceptional EFTs like the non-linear sigma model, Dirac-Born-Infeld theory, and the special Galileon lie precisely on the boundary of allowed theory space. Using on-shell momentum shifts and recursion relations, we prove that EFTsmore » with arbitrarily soft behavior are forbidden and EFTs with leading valency much greater than the spacetime dimension cannot have enhanced soft behavior. We then enumerate all single scalar EFTs in d < 6 and verify that they correspond to known theories in the literature. Finally, our results suggest that the exceptional theories are the natural EFT analogs of gauge theory and gravity because they are one-parameter theories whose interactions are strictly dictated by properties of the S-matrix.« less
Extracting Neutron Polarizabilities from Compton Scattering on Quasi-Free Neutrons in γd -> γnp
NASA Astrophysics Data System (ADS)
Demissie, Berhan
2017-01-01
Compton scattering processes are ideal to study electric and magnetic dipole polarizability coefficients of nucleons. These fundamental quantities parametrize the response to a monochromatic photon probe. In this work, the inelastic channel γd -> γnp is treated in χEFT, with a focus on the NQFP - neutron quasi-free peak - kinematic region. In this region, the momentum of the outgoing proton is small enough that it is considered to remain at rest. This provides access to the Compton scattering process γn -> γn from which the neutron scalar polarizabilites α and β are extracted. Using χEFT, differential cross-sections, d3 σ / dEn dΩγ'Ωn , in the photon energy range of 200-400 MeV are computed. The biggest contribution comes from the impulse approximation, with small corrections stemming from final state interaction, meson exchange currents and rescattering. A new extraction of neutron polarizabilities from a two-parameter fit to the Kossert et al. data taken at MAMI in 2002 is presented. This work is supported by the US Department of Energy under contracts DE-FG02- 95ER-40907, and by the Dean's Research Chair programme of the Columbian College of Arts and Sciences of The George Washington University.
High-Accuracy Analysis of Compton Scattering in Chiral EFT: Proton and Neutron Polarisabilities
NASA Astrophysics Data System (ADS)
Griesshammer, Harald W.; Phillips, Daniel R.; McGovern, Judith A.
2013-10-01
Compton scattering from protons and neutrons provides important insight into the structure of the nucleon. A new extraction of the static electric and magnetic dipole polarisabilities αE 1 and βM 1 of the proton and neutron from all published elastic data below 300 MeV in Chiral Effective Field Theory shows that within the statistics-dominated errors, the proton and neutron polarisabilities are identical, i.e. no iso-spin breaking effects of the pion cloud are seen. Particular attention is paid to the precision and accuracy of each data set, and to an estimate of residual theoretical uncertainties. ChiEFT is ideal for that purpose since it provides a model-independent estimate of higher-order corrections and encodes the correct low-energy dynamics of QCD, including, for few-nucleon systems used to extract neutron polarisabilities, consistent nuclear currents, rescattering effects and wave functions. It therefore automatically respects the low-energy theorems for photon-nucleus scattering. The Δ (1232) as active degree of freedom is essential to realise the full power of the world's Compton data.Its parameters are constrained in the resonance region. A brief outlook is provided on what kind of future experiments can improve the database. Supported in part by UK STFC, DOE, NSF, and the Sino-German CRC 110.
Ormand, W. E.; Brown, B. A.; Hjorth-Jensen, M.
2017-08-01
We present calculations for the c coefficients of the isobaric mass multiplet equation for nuclei from A = 42 to A = 54 based on input from three realistic nucleon-nucleon interactions. We demonstrate that there is a clear dependence on the short-range charge-symmetry-breaking (CSB) part of the strong interaction and that there is significant disagreement in the CSB part between the commonly used CD-Bonn, chiral effective field theory at next-to-next-to-next-to-leading-order, and Argonne V18 nucleon-nucleon interactions. In addition, we show that all three interactions give a CSB contribution to the c coefficient that is too large when compared to experiment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ormand, W. E.; Brown, B. A.; Hjorth-Jensen, M.
We present calculations for the c coefficients of the isobaric mass multiplet equation for nuclei from A = 42 to A = 54 based on input from three realistic nucleon-nucleon interactions. We demonstrate that there is a clear dependence on the short-range charge-symmetry-breaking (CSB) part of the strong interaction and that there is significant disagreement in the CSB part between the commonly used CD-Bonn, chiral effective field theory at next-to-next-to-next-to-leading-order, and Argonne V18 nucleon-nucleon interactions. In addition, we show that all three interactions give a CSB contribution to the c coefficient that is too large when compared to experiment.
NASA Astrophysics Data System (ADS)
Alarcón, J. M.; Weiss, C.
2018-05-01
We study the nucleon electromagnetic form factors (EM FFs) using a recently developed method combining chiral effective field theory (χ EFT ) and dispersion analysis. The spectral functions on the two-pion cut at t >4 Mπ2 are constructed using the elastic unitarity relation and an N /D representation. χ EFT is used to calculate the real functions J±1(t ) =f±1(t ) /Fπ(t ) (ratios of the complex π π →N N ¯ partial-wave amplitudes and the timelike pion FF), which are free of π π rescattering. Rescattering effects are included through the empirical timelike pion FF | Fπ(t) | 2 . The method allows us to compute the isovector EM spectral functions up to t ˜1 GeV2 with controlled accuracy (leading order, next-to-leading order, and partial next-to-next-to-leading order). With the spectral functions we calculate the isovector nucleon EM FFs and their derivatives at t =0 (EM radii, moments) using subtracted dispersion relations. We predict the values of higher FF derivatives, which are not affected by higher-order chiral corrections and are obtained almost parameter-free in our approach, and explain their collective behavior. We estimate the individual proton and neutron FFs by adding an empirical parametrization of the isoscalar sector. Excellent agreement with the present low-Q2 FF data is achieved up to ˜0.5 GeV2 for GE, and up to ˜0.2 GeV2 for GM. Our results can be used to guide the analysis of low-Q2 elastic scattering data and the extraction of the proton charge radius.
Properties of Nuclei up to A = 16 using Local Chiral Interactions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lonardoni, Diego; Carlson, Joseph; Gandolfi, Stefano
Here, we report accurate quantum Monte Carlo calculations of nuclei up to A = 16 based on local chiral two- and three-nucleon interactions up to next-to-next-to-leading order. We examine the theoretical uncertainties associated with the chiral expansion and the cutoff in the theory, as well as the associated operator choices in the three-nucleon interactions. While in light nuclei the cutoff variation and systematic uncertainties are rather small, in 16O these can be significant for large coordinate-space cutoffs. Overall, we show that chiral interactions constructed to reproduce properties of very light systems and nucleon-nucleon scattering give an excellent description of bindingmore » energies, charge radii, and form factors for all these nuclei, including open-shell systems in A = 6 and 12.« less
Properties of Nuclei up to A = 16 using Local Chiral Interactions
Lonardoni, Diego; Carlson, Joseph; Gandolfi, Stefano; ...
2018-03-22
Here, we report accurate quantum Monte Carlo calculations of nuclei up to A = 16 based on local chiral two- and three-nucleon interactions up to next-to-next-to-leading order. We examine the theoretical uncertainties associated with the chiral expansion and the cutoff in the theory, as well as the associated operator choices in the three-nucleon interactions. While in light nuclei the cutoff variation and systematic uncertainties are rather small, in 16O these can be significant for large coordinate-space cutoffs. Overall, we show that chiral interactions constructed to reproduce properties of very light systems and nucleon-nucleon scattering give an excellent description of bindingmore » energies, charge radii, and form factors for all these nuclei, including open-shell systems in A = 6 and 12.« less
Algebraic diagrammatic construction formalism with three-body interactions
NASA Astrophysics Data System (ADS)
Raimondi, Francesco; Barbieri, Carlo
2018-05-01
Background: Self-consistent Green's function theory has recently been extended to the basic formalism needed to account for three-body interactions [Carbone, Cipollone, Barbieri, Rios, and Polls, Phys. Rev. C 88, 054326 (2013), 10.1103/PhysRevC.88.054326]. The contribution of three-nucleon forces has so far been included in ab initio calculations on nuclear matter and finite nuclei only as averaged two-nucleon forces. Purpose: We derive the working equations for all possible two- and three-nucleon terms that enter the expansion of the self-energy up to the third order, thus including the interaction-irreducible (i.e., not averaged) diagrams with three-nucleon forces that have been previously neglected. Methods: We employ the algebraic diagrammatic construction up to the third order as an organization scheme for generating a nonperturbative self-energy, in which ring (particle-hole) and ladder (particle-particle) diagrams are resummed to all orders. Results: We derive expressions of the static and dynamic self-energy up to the third order, by taking into account the set of diagrams required when either the skeleton or nonskeleton expansions of the single-particle propagator are assumed. A hierarchy of importance among different diagrams is revealed, and a particular emphasis is given to a third-order diagram [see Fig. 2(c)] that is expected to play a significant role among those featuring an interaction-irreducible three-nucleon force. Conclusion: A consistent formalism to resum at infinite order correlations induced by three-nucleon forces in the self-consistent Green's function theory is now available and ready to be implemented in the many-body solvers.
Three-cluster dynamics within an ab initio framework
Quaglioni, Sofia; Romero-Redondo, Carolina; Navratil, Petr
2013-09-26
In this study, we introduce a fully antisymmetrized treatment of three-cluster dynamics within the ab initio framework of the no-core shell model/resonating-group method. Energy-independent nonlocal interactions among the three nuclear fragments are obtained from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with bound-state boundary conditions by means of the hyperspherical-harmonic method on a Lagrange mesh. We discuss the formalism in detail and give algebraic expressions for systems of two single nucleons plus a nucleus. Using a soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we apply the method to amore » 4He+n+n description of 6He and compare the results to experiment and to a six-body diagonalization of the Hamiltonian performed within the harmonic-oscillator expansions of the no-core shell model. Differences between the two calculations provide a measure of core ( 4He) polarization effects.« less
The quest for novel modes of excitation in exotic nuclei
NASA Astrophysics Data System (ADS)
Paar, N.
2010-06-01
This paper provides an insight into several open problems in the quest for novel modes of excitation in nuclei with isospin asymmetry, deformation and finite-temperature characteristics in stellar environments. Major unsolved problems include the nature of pygmy dipole resonances, the quest for various multipole and spin-isospin excitations both in neutron-rich and proton drip-line nuclei mainly driven by loosely bound nucleons, excitations in unstable deformed nuclei and evolution of their properties with the shape phase transition. Exotic modes of excitation in nuclei at finite temperatures characteristic of supernova evolution present open problems with a possible impact in modeling astrophysically relevant weak interaction rates. All these issues challenge self-consistent many-body theory frameworks at the frontiers of on-going research, including nuclear energy density functionals, both phenomenological and constrained by the strong interaction physics of QCD, models based on low-momentum two-nucleon interaction Vlow-k and correlated realistic nucleon-nucleon interaction VUCOM, supplemented by three-body force, as well as two-nucleon and three-nucleon interactions derived from the chiral effective field theory. Joined theoretical and experimental efforts, including research with radioactive isotope beams, are needed to provide insight into dynamical properties of nuclei away from the valley of stability, involving the interplay of isospin asymmetry, deformation and finite temperature.
Ab initio description of p-shell hypernuclei.
Wirth, Roland; Gazda, Daniel; Navrátil, Petr; Calci, Angelo; Langhammer, Joachim; Roth, Robert
2014-11-07
We present the first ab initio calculations for p-shell single-Λ hypernuclei. For the solution of the many-baryon problem, we develop two variants of the no-core shell model with explicit Λ and Σ(+),Σ(0),Σ(-) hyperons including Λ-Σ conversion, optionally supplemented by a similarity renormalization group transformation to accelerate model-space convergence. In addition to state-of-the-art chiral two- and three-nucleon interactions, we use leading-order chiral hyperon-nucleon interactions and a recent meson-exchange hyperon-nucleon interaction. We validate the approach for s-shell hypernuclei and apply it to p-shell hypernuclei, in particular to (Λ)(7)Li, (Λ)(9)Be, and (Λ)(13)C. We show that the chiral hyperon-nucleon interactions provide ground-state and excitation energies that generally agree with experiment within the cutoff dependence. At the same time we demonstrate that hypernuclear spectroscopy provides tight constraints on the hyperon-nucleon interactions.
Scattering calculations and confining interactions
NASA Technical Reports Server (NTRS)
Buck, Warren W.; Maung, Khin M.
1993-01-01
Most of the research work performed under this grant were concerned with strong interaction processes ranging from kaon-nucleon interaction to proton-nucleus scattering calculations. Research performed under this grant can be categorized into three groups: (1) parametrization of fundamental interactions, (2) development of formal theory, and (3) calculations based upon the first two. Parametrizations of certain fundamental interactions, such as kaon-nucleon interaction, for example, were necessary because kaon-nucleon scattering amplitude was needed to perform kaon-nucleus scattering calculations. It was possible to calculate kaon-nucleon amplitudes from the first principle, but it was unnecessary for the purpose of the project. Similar work was also done for example for anti-protons and anti-nuclei. Formal developments to some extent were also pursued so that consistent calculations can be done.
Origin of the anomalous long lifetime of ¹⁴C.
Maris, P; Vary, J P; Navrátil, P; Ormand, W E; Nam, H; Dean, D J
2011-05-20
We report the microscopic origins of the anomalously suppressed beta decay of ¹⁴C to ¹⁴N using the ab initio no-core shell model with the Hamiltonian from the chiral effective field theory including three-nucleon force terms. The three-nucleon force induces unexpectedly large cancellations within the p shell between contributions to beta decay, which reduce the traditionally large contributions from the nucleon-nucleon interactions by an order of magnitude, leading to the long lifetime of ¹⁴C.
Structure of the Lightest Tin Isotopes
NASA Astrophysics Data System (ADS)
Morris, T. D.; Simonis, J.; Stroberg, S. R.; Stumpf, C.; Hagen, G.; Holt, J. D.; Jansen, G. R.; Papenbrock, T.; Roth, R.; Schwenk, A.
2018-04-01
We link the structure of nuclei around 100Sn, the heaviest doubly magic nucleus with equal neutron and proton numbers (N =Z =50 ), to nucleon-nucleon (N N ) and three-nucleon (N N N ) forces constrained by data of few-nucleon systems. Our results indicate that 100Sn is doubly magic, and we predict its quadrupole collectivity. We present precise computations of 101Sn based on three-particle-two-hole excitations of 100Sn, and we find that one interaction accurately reproduces the small splitting between the lowest Jπ=7 /2+ and 5 /2+ states.
Analysis of drug use in institutionalized individuals with intellectual disability and tube feeding.
Joos, Elke; Mehuys, Els; Remon, Jean Paul; Van Winckel, Myriam; Boussery, Koen
2016-04-01
Little is known about the medication used by people with intellectual disabilities (ID) and enteral feeding tube (EFT). However, in light of the complexity associated with drug administration through EFT, data on medication use in this population may be helpful in the development of practical guidelines and staff training initiatives. A cross-sectional, observational study was conducted in six Belgian residential care facilities (RCFs) for individuals with ID. Anonymized medication records of all residents receiving chronic medication through EFT were collected (n = 156). All chronic drugs were categorized according to the ATC classification, and medication records were checked for potential major drug-drug interactions (DDI). The 156 residents used a total of 1029 chronic drugs via EFT, with a median of six drugs per resident (range 1-14). A total of 148 different drug molecules were identified, belonging to 38 main ATC therapeutic groups (ATC level 2). Antiepileptics, drugs for constipation and drugs for acid-related disorders were the most frequently used groups. Seventy-four of the 156 screened medication records (47%) contained at least one potential DDI; in total, 116 potential interactions were identified, which represent 38 different interacting drug pairs. This study describes medication use through EFT among people with ID in Belgian RCFs, with antiepileptics being the most frequently used group. Our study also demonstrated that a high number of drugs is administered through EFT, and that the number of potential DDIs is high. These observations warrant an increased attention for drug administration through the EFT in individuals with ID.
4He binding energy calculation including full tensor-force effects
NASA Astrophysics Data System (ADS)
Fonseca, A. C.
1989-09-01
The four-body equations of Alt, Grassberger, and Sandhas are solved in the version where the (2)+(2) subamplitudes are treated exactly by convolution, using one-term separable Yamaguchy nucleon-nucleon potentials in the 1S0 and 3S1-3D1 channels. The resulting jp=1/2+ and (3/2+ three-body subamplitudes are represented in a separable form using the energy-dependent pole expansion. Converged bound-state results are calculated for the first time using the full interaction, and are compared with those obtained from a simplified treatment of the tensor force. The Tjon line that correlates three-nucleon and four-nucleon binding energies is shown using different nucleon-nucleon potentials. In all calculations the Coulomb force has been neglected.
Effective field theory in the harmonic oscillator basis
Binder, S.; Ekström, Jan A.; Hagen, Gaute; ...
2016-04-25
In this paper, we develop interactions from chiral effective field theory (EFT) that are tailored to the harmonic oscillator basis. As a consequence, ultraviolet convergence with respect to the model space is implemented by construction and infrared convergence can be achieved by enlarging the model space for the kinetic energy. In oscillator EFT, matrix elements of EFTs formulated for continuous momenta are evaluated at the discrete momenta that stem from the diagonalization of the kinetic energy in the finite oscillator space. By fitting to realistic phase shifts and deuteron data we construct an effective interaction from chiral EFT at next-to-leadingmore » order. Finally, many-body coupled-cluster calculations of nuclei up to 132Sn converge fast for the ground-state energies and radii in feasible model spaces.« less
Analysis of general power counting rules in effective field theory
Gavela, Belen; Jenkins, Elizabeth E.; Manohar, Aneesh V.; ...
2016-09-02
We derive the general counting rules for a quantum effective field theory (EFT) in d dimensions. The rules are valid for strongly and weakly coupled theories, and they predict that all kinetic energy terms are canonically normalized. They determine the energy dependence of scattering cross sections in the range of validity of the EFT expansion. We show that the size of the cross sections is controlled by the Λ power counting of EFT, not by chiral counting, even for chiral perturbation theory (χPT). The relation between Λ and f is generalized to d dimensions. We show that the naive dimensionalmore » analysis 4π counting is related to ℏ counting. The EFT counting rules are applied to χPT, low-energy weak interactions, Standard Model EFT and the non-trivial case of Higgs EFT.« less
Induced Hyperon-Nucleon-Nucleon Interactions and the Hyperon Puzzle.
Wirth, Roland; Roth, Robert
2016-10-28
We present the first ab initio calculations for p-shell hypernuclei including hyperon-nucleon-nucleon (YNN) contributions induced by a similarity renormalization group transformation of the initial hyperon-nucleon interaction. The transformation including the YNN terms conserves the spectrum of the Hamiltonian while drastically improving model-space convergence of the importance-truncated no-core model, allowing a precise extraction of binding and excitation energies. Results using a hyperon-nucleon interaction at leading order in chiral effective field theory for lower- to mid-p-shell hypernuclei show a good reproduction of experimental excitation energies while hyperon separation energies are typically overestimated. The induced YNN contributions are strongly repulsive and we show that they are related to a decoupling of the Σ hyperons from the hypernuclear system, i.e., a suppression of the Λ-Σ conversion terms in the Hamiltonian. This is linked to the so-called hyperon puzzle in neutron-star physics and provides a basic mechanism for the explanation of strong ΛNN three-baryon forces.
NASA Astrophysics Data System (ADS)
Ismail, M.; Seif, W. M.; Botros, M. M.
2016-04-01
We investigate the fusion cross-section and the fusion barrier distribution of 16O +238U at near- and sub-barrier energies. We use an interaction potential generated by the semi-microscopic double folding model-based on density dependent (DD) form of the realistic Michigan-three-Yukawa (M3Y) Reid nucleon-nucleon (NN) interaction. We studied the role of both the static and dynamic deformations of the target nucleus on the fusion process. Rotational and vibrational degrees of freedom of 238U-nucleus are considered. We found that the deformation and the octupole vibrations in 238U enhance its sub-barrier fusion cross-section. The signature of the the octupole vibrational modes of 238U appears clearly in its fusion barrier distribution profile.
Neutrino Opacity in High Density Nuclear Matter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Santos, Sergio M. dos; Razeira, Moises; Vasconcellos, Cesar A.Z.
2004-12-02
We estimate the contribution of the nucleon weak magnetism on the neutrino absorption mean free path inside high density nuclear matter. In the mean field approach, three different ingredients are taken into account: (a) a relativistic generalization of the approach developed by Sanjay et al.; (b) the inclusion of the nucleon weak-magnetism (c) and the pseudo-scalar interaction involving the nucleons. Our main result shows that the neutrino absorption mean free path is three times the corresponding result obtained by those authors.
Δ isobars and nuclear saturation
NASA Astrophysics Data System (ADS)
Ekström, A.; Hagen, G.; Morris, T. D.; Papenbrock, T.; Schwartz, P. D.
2018-02-01
We construct a nuclear interaction in chiral effective field theory with explicit inclusion of the Δ -isobar Δ (1232 ) degree of freedom at all orders up to next-to-next-to-leading order (NNLO). We use pion-nucleon (π N ) low-energy constants (LECs) from a Roy-Steiner analysis of π N scattering data, optimize the LECs in the contact potentials up to NNLO to reproduce low-energy nucleon-nucleon scattering phase shifts, and constrain the three-nucleon interaction at NNLO to reproduce the binding energy and point-proton radius of 4He. For heavier nuclei we use the coupled-cluster method to compute binding energies, radii, and neutron skins. We find that radii and binding energies are much improved for interactions with explicit inclusion of Δ (1232 ) , while Δ -less interactions produce nuclei that are not bound with respect to breakup into α particles. The saturation of nuclear matter is significantly improved, and its symmetry energy is consistent with empirical estimates.
Iowa State University – Final Report for SciDAC3/NUCLEI
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vary, James P
The Iowa State University (ISU) contributions to the NUCLEI project are focused on developing, implementing and running an efficient and scalable configuration interaction code (Many-Fermion Dynamics – nuclear or MFDn) for leadership class supercomputers addressing forefront research problems in low-energy nuclear physics. We investigate nuclear structure and reactions with realistic nucleon-nucleon (NN) and three-nucleon (3N) interactions. We select a few highlights from our work that has produced a total of more than 82 refereed publications and more than 109 invited talks under SciDAC3/NUCLEI.
Electromagnetic Structure of A=2 and 3 Nuclei and the Nuclear Current Operator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rocco Schiavilla
Different models for conserved two- and three-body electromagnetic currents are constructed from two- and three-nucleon interactions, using either meson-exchange mechanisms or minimal substitution in the momentum dependence of these interactions. The connection between these two different schemes is elucidated. A number of low-energy electronuclear observables, including (i) np radiative capture at thermal neutron energies and deuteron photodisintegration at low energies, (ii) nd and pd radiative capture reactions, and (iii) isoscalar and isovector magnetic form factors of {sup 3}H and {sup 3}He, are calculated in order to make a comparative study of these models for the current operator. The realistic Argonnemore » v{sub 18} two-nucleon and Urbana IX or Tucson-Melbourne three-nucleon interactions are taken as a case study. For A=3 processes, the bound and continuum wave functions, both below and above deuteron breakup threshold, are obtained with the correlated hyperspherical-harmonics method. Three-body currents give small but significant contributions to some of the polarization observables in the {sup 2}H(p,{gamma}){sup 3}He process and the {sup 2}H(n,{gamma}){sup 3}H cross section at thermal neutron energies. It is shown that the use of a current which did not exactly satisfy current conservation with the two- and three-nucleon interactions in the Hamiltonian was responsible for some of the discrepancies reported in previous studies between the experimental and theoretical polarization observables in pd radiative capture.« less
Coherent neutrinoproduction of photons and pions in a chiral effective field theory for nuclei
NASA Astrophysics Data System (ADS)
Zhang, Xilin; Serot, Brian D.
2012-09-01
Background: The neutrinoproduction of photons and pions from nucleons and nuclei is relevant to the background analysis in neutrino-oscillation experiments [for example, the MiniBooNE; MiniBooNE Collaboration, A. A. Aquilar-Arevalo , Phys. Rev. Lett.0031-900710.1103/PhysRevLett.100.032301 100, 032301 (2008)]. The production from nucleons and incoherent production with Eν⩽0.5GeV have been studied in B. D. Serot and X. Zhang, Phys. Rev. CPRVCAN0556-281310.1103/PhysRevC.86.015501 86, 015501 (2012); and X. Zhang and B. D. Serot, Phys. Rev. C1110-865710.1103/PhysRevC.86.035502 86, 035502 (2012).Purpose: Study coherent productions with Eν⩽0.5GeV. Also address the contributions of two contact terms in neutral current (NC) photon production that are partially related to the proposed anomalous ω(ρ), Z boson, and photon interactions.Methods: We work in the framework of a Lorentz-covariant effective field theory (EFT), which contains nucleons, pions, the Δ (1232) (Δs), isoscalar scalar (σ) and vector (ω) fields, and isovector vector (ρ) fields, and incorporates a nonlinear realization of (approximate) SU(2)L⊗SU(2)R chiral symmetry. A revised version of the so-called “optimal approximation” is applied, where one-nucleon interaction amplitude is factorized out and the medium-modifications and pion wave function distortion are included. The calculation is tested against the coherent pion photoproduction data.Results: The computation shows an agreement with the pion photoproduction data, although precisely determining the Δ modification is entangled with one mentioned contact term. The uncertainty in the Δ modification leads to uncertainties in both pion and photon neutrinoproductions. In addition, the contact term plays a significant role in NC photon production.Conclusions: First, the contact term increases NC photon production by ˜10% assuming a reasonable range of the contact coupling, which however seems not significant enough to explain the MiniBooNE excess. A high energy computation is needed to gain a firm conclusion and will be presented elsewhere. Second, the behavior of coherent neutrinoproductions computed here is significantly different from the expectation at high energy by ignoring the vector current contribution.
NASA Astrophysics Data System (ADS)
Li, Cheng; Tian, Jun-Long; Wang, Ning
2013-11-01
The nucleon-nucleon interaction is investigated by using the ImQMD model with the three sets of parameters IQ1, IQ2 and IQ3 in which the corresponding incompressibility coefficients of nuclear matter are different. Fusion excitation function and the charge distribution of fragments are calculated for reaction systems 40Ca+40Ca at different incident energies. It is found that obvious differences in the charge distribution were observed at the energy region 10-25A MeV by adopting the three sets of parameters, while the results were close to each other at energy region of 30-45A MeV for the reaction system. It indicates that the Fermi energy region is a sensitive energy region to explore the N-N interaction. The fragment multiplicity spectrum for 238U+197Au at 15A MeV are reproduced by the ImQMD model with the set of parameter IQ3. It is concluded that charge distribution of the fragments and the fragment multiplicity spectrum are good observables for studying N-N interaction, and IQ3 is a suitable set of parameters for the ImQMD model.
Nuclear matter from effective quark-quark interaction.
Baldo, M; Fukukawa, K
2014-12-12
We study neutron matter and symmetric nuclear matter with the quark-meson model for the two-nucleon interaction. The Bethe-Bruckner-Goldstone many-body theory is used to describe the correlations up to the three hole-line approximation with no extra parameters. At variance with other nonrelativistic realistic interactions, the three hole-line contribution turns out to be non-negligible and to have a substantial saturation effect. The saturation point of nuclear matter, the compressibility, the symmetry energy, and its slope are within the phenomenological constraints. Since the interaction also reproduces fairly well the properties of the three-nucleon system, these results indicate that the explicit introduction of the quark degrees of freedom within the considered constituent quark model is expected to reduce the role of three-body forces.
Transverse Densities of Octet Baryons from Chiral Effective Field Theory
Alarcón, Jose Manuel; Hiller Blin, Astrid N.; Weiss, Christian
2017-03-24
Transverse densities describe the distribution of charge and current at fixed light-front time and provide a frame-independent spatial representation of hadrons as relativistic systems. In this paper, we calculate the transverse densities of the octet baryons at peripheral distances b=O(M π -1) in an approach that combines chiral effective field theory (χχEFT) and dispersion analysis. The densities are represented as dispersive integrals of the imaginary parts of the baryon electromagnetic form factors in the timelike region (spectral functions). The spectral functions on the two-pion cut at t>4Mmore » $$2\\atop{π}$$ are computed using relativistic χEFT with octet and decuplet baryons in the extended on-mass-shell renormalization scheme. The calculations are extended into the ρ-meson mass region using a dispersive method that incorporates the timelike pion form-factor data. The approach allows us to construct densities at distances b>1 fm with controlled uncertainties. Finally, our results provide insight into the peripheral structure of nucleons and hyperons and can be compared with empirical densities and lattice-QCD calculations.« less
Semilocal momentum-space regularized chiral two-nucleon potentials up to fifth order
NASA Astrophysics Data System (ADS)
Reinert, P.; Krebs, H.; Epelbaum, E.
2018-05-01
We introduce new semilocal two-nucleon potentials up to fifth order in the chiral expansion. We employ a simple regularization approach for the pion exchange contributions which i) maintains the long-range part of the interaction, ii) is implemented in momentum space and iii) can be straightforwardly applied to regularize many-body forces and current operators. We discuss in detail the two-nucleon contact interactions at fourth order and demonstrate that three terms out of fifteen used in previous calculations can be eliminated via suitably chosen unitary transformations. The removal of the redundant contact terms results in a drastic simplification of the fits to scattering data and leads to interactions which are much softer ( i.e., more perturbative) than our recent semilocal coordinate-space regularized potentials. Using the pion-nucleon low-energy constants from matching pion-nucleon Roy-Steiner equations to chiral perturbation theory, we perform a comprehensive analysis of nucleon-nucleon scattering and the deuteron properties up to fifth chiral order and study the impact of the leading F-wave two-nucleon contact interactions which appear at sixth order. The resulting chiral potentials at fifth order lead to an outstanding description of the proton-proton and neutron-proton scattering data from the self-consistent Granada-2013 database below the pion production threshold, which is significantly better than for any other chiral potential. For the first time, the chiral potentials match in precision and even outperform the available high-precision phenomenological potentials, while the number of adjustable parameters is, at the same time, reduced by about ˜ 40%. Last but not least, we perform a detailed error analysis and, in particular, quantify for the first time the statistical uncertainties of the fourth- and the considered sixth-order contact interactions.
4He+n+n continuum within an ab initio framework
Romero-Redondo, Carolina; Quaglioni, Sofia; Navratil, Petr; ...
2014-07-16
In this study, the low-lying continuum spectrum of the 6He nucleus is investigated for the first time within an ab initio framework that encompasses the 4He+n+n three-cluster dynamics characterizing its lowest decay channel. This is achieved through an extension of the no-core shell model combined with the resonating-group method, in which energy-independent nonlocal interactions among three nuclear fragments can be calculated microscopically, starting from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with three-body scattering boundary conditions by means of the hyperspherical-harmonics method on a Lagrange mesh. Using amore » soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we find the known J π = 2 + resonance as well as a result consistent with a new low-lying second 2 + resonance recently observed at GANIL at ~2.6 MeV above the He6 ground state. We also find resonances in the 2 –, 1 +, and 0 – channels, while no low-lying resonances are present in the 0 + and 1 – channels.« less
Spin-isospin excitation of 3He with three-proton final state
NASA Astrophysics Data System (ADS)
Ishikawa, Souichi
2018-01-01
Spin-isospin excitation of the {}^3He nucleus by a proton-induced charge exchange reaction, {}^3He(p,n)ppp, at forward neutron scattering angle is studied in a plane wave impulse approximation (PWIA). In PWIA, cross sections of the reaction are written in terms of proton-neutron scattering amplitudes and response functions of the transition from {}3He to the three-proton state by spin-isospin transition operators. The response functions are calculated with realistic nucleon-nucleon potential models using a Faddeev three-body method. Calculated cross sections agree with available experimental data in substance. Possible effects arising from the uncertainty of proton-neutron amplitudes and three-nucleon interactions in the three-proton system are examined.
Model-independent description of quartet nd scattering at low energies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grinyuk, B.E.; Simenog, I.V.; Sitnichenko, A.I.
1984-02-01
Asymptotic expansions are obtained for the scattering length a/sub 3//sub ///sub 2/ and the effective range r/sub 3//sub ///sub 2/ for the quartet state of three nucleons in the form of series in powers of the two-nucleon triplet effective range r/sub 0t/. This allows a model-independent description of these parameters and of the quartet phase shift of nd scattering in the effective-range approximation. Correlations between the parameters of three- and two-nucleon scattering are proposed and explained; these correlations allow the systematization of numerical calculations of a/sub 3//sub ///sub 2/ and r/sub 3//sub ///sub 2/ for different forms of interaction potentials.more » The influence of the energy dependence of the interaction on a/sub 3//sub ///sub 2/ is also considered.« less
NASA Astrophysics Data System (ADS)
Kohno, M.
2018-03-01
Adopting hyperon-nucleon and hyperon-nucleon-nucleon interactions parametrized in chiral effective field theory, single-particle potentials of the Λ and Σ hyperons are evaluated in symmetric nuclear matter and in pure neutron matter within the framework of lowest-order Bruckner theory. The chiral NLO interaction bears strong Λ N -Σ N coupling. Although the Λ potential is repulsive if the coupling is switched off, the Λ N -Σ N correlation brings about the attraction consistent with empirical data. The Σ potential is repulsive, which is also consistent with empirical information. The interesting result is that the Λ potential becomes shallower beyond normal density. This provides the possibility of solving the hyperon puzzle without introducing ad hoc assumptions. The effects of the Λ N N -Λ N N and Λ N N -Σ N N three-baryon forces are considered. These three-baryon forces are first reduced to normal-ordered effective two-baryon interactions in nuclear matter and then incorporated in the G -matrix equation. The repulsion from the Λ N N -Λ N N interaction is of the order of 5 MeV at normal density and becomes larger with increasing density. The effects of the Λ N N -Σ N N coupling compensate the repulsion at normal density. The net effect of the three-baryon interactions on the Λ single-particle potential is repulsive at higher densities.
K- absorption on two nucleons and ppK- bound state search in the Σ0p final state
NASA Astrophysics Data System (ADS)
Vázquez Doce, O.; Fabbietti, L.; Cargnelli, M.; Curceanu, C.; Marton, J.; Piscicchia, K.; Scordo, A.; Sirghi, D.; Tucakovic, I.; Wycech, S.; Zmeskal, J.; Anastasi, A.; Curciarello, F.; Czerwinski, E.; Krzemien, W.; Mandaglio, G.; Martini, M.; Moskal, P.; Patera, V.; Pérez del Rio, E.; Silarski, M.
2016-07-01
We report the measurement of K- absorption processes in the Σ0p final state and the first exclusive measurement of the two nucleon absorption (2NA) with the KLOE detector. The 2NA process without further interactions is found to be 9% of the sum of all other contributing processes, including absorption on three and more nucleons or 2NA followed by final state interactions with the residual nucleons. We also determine the possible contribution of the ppK- bound state to the Σ0p final state. The yield of ppK- /Kstop- is found to be (0.044 ± 0.009stat-0.005+0.004 syst) ṡ10-2 but its statistical significance based on an F-test is only 1σ.
Numerical Exact Ab Initio Four-Nucleon Scattering Calculations: from Dream to Reality
NASA Astrophysics Data System (ADS)
Fonseca, A. C.; Deltuva, A.
2017-03-01
In the present manuscript we review the work of the last ten years on the pursuit to obtain numerical exact solutions of the four-nucleon scattering problem using the most advanced force models that fit two nucleon data up to pion production threshold with a χ ^2 per data point approximately one, together with the Coulomb interaction between protons; three- and four-nucleon forces are also included in the framework of a meson exchange potential model where NN couples to NΔ. Failure to describe the world data on four-nucleon scattering observables in the framework of a non relativistic scattering approach falls necessarily on the force models one uses. Four-nucleon observables pose very clear challenges, particular in the low energy region where there are a number of resonances whose position and width needs to be dynamically generated by the nucleon-nucleon (NN) interactions one uses. In addition, our calculations constitute the most advance piece of work where observables for all four-nucleon reactions involving isospin I=0, I=0 coupled to I=1 and isospin I=1 initial states are calculated at energies both below and above breakup threshold. We also present a very extensive comparison between calculated results and data for cross sections and spin observables. Therefore the present work reveals both the shortcomings and successes of some of the present NN force models in describing four-nucleon data and serve as a benchmark for future developments.
Neutron Measurements and the Weak Nucleon-Nucleon Interaction
Snow, W. M.
2005-01-01
The weak interaction between nucleons remains one of the most poorly-understood sectors of the Standard Model. A quantitative description of this interaction is needed to understand weak interaction phenomena in atomic, nuclear, and hadronic systems. This paper summarizes briefly what is known about the weak nucleon-nucleon interaction, tries to place this phenomenon in the context of other studies of the weak and strong interactions, and outlines a set of measurements involving low energy neutrons which can lead to significant experimental progress. PMID:27308120
Single pion production in neutrino-nucleon interactions
NASA Astrophysics Data System (ADS)
Kabirnezhad, M.
2018-01-01
This work represents an extension of the single pion production model proposed by Rein [Z. Phys. C 35, 43 (1987)., 10.1007/BF01561054]. The model consists of resonant pion production and nonresonant background contributions coming from three Born diagrams in the helicity basis. The new work includes lepton mass effects, and nonresonance interaction is described by five diagrams based on a nonlinear σ model. This work provides a full kinematic description of single pion production in the neutrino-nucleon interactions, including resonant and nonresonant interactions in the helicity basis, in order to study the interference effect.
Nucleon-deuteron scattering with the JISP16 potential
NASA Astrophysics Data System (ADS)
Skibiński, R.; Golak, J.; Topolnicki, K.; Witała, H.; Volkotrub, Yu.; Kamada, H.; Shirokov, A. M.; Okamoto, R.; Suzuki, K.; Vary, J. P.
2018-01-01
The nucleon-nucleon J -matrix inverse scattering potential JISP16 is applied to elastic nucleon-deuteron scattering and the deuteron breakup process at the laboratory nucleon energies up to 135 MeV. The formalism of the Faddeev equations is used to obtain three-nucleon scattering states. We compare predictions based on the JISP16 force with data and with results based on various two-body interactions, including the CD Bonn, the Argonne AV18, the chiral force with the semilocal regularization at the fifth order of the chiral expansion and with low-momentum interactions obtained from the CD Bonn force as well as with the predictions from the combination of the AV18 NN interaction and the Urbana IX 3 N force. JISP16 provides a satisfactory description of some observables at low energies but strong deviations from data as well as from standard and chiral potential predictions with increasing energy. However, there are also polarization observables at low energies for which the JISP16 predictions differ from those based on the other forces by a factor of two. The reason for such a behavior can be traced back to the P -wave components of the JISP16 force. At higher energies the deviations can be enhanced by an interference with higher partial waves and by the properties of the JISP16 deuteron wave function. In addition, we compare the energy and angular dependence of predictions based on the JISP16 force with the results of the low-momentum interactions obtained with different values of the momentum cutoff parameter. We found that such low-momentum forces can be employed to interpret the nucleon-deuteron elastic scattering data only below some specific energy which depends on the cutoff parameter. Since JISP16 is defined in a finite oscillator basis, it has properties similar to low momentum interactions and its application to the description of nucleon-deuteron scattering data is limited to a low momentum transfer region.
Studies of the Three-Nucleon System Dynamics in the Deuteron-Proton Breakup Reaction
NASA Astrophysics Data System (ADS)
Ciepał, I.; Kłos, B.; Stephan, E.; Kistryn, St.; Biegun, A.; Bodek, K.; Deltuva, A.; Epelbaum, E.; Eslami-Kalantari, M.; Fonseca, A. C.; Golak, J.; Jha, V.; Kalantar-Nayestanaki, N.; Kamada, H.; Khatri, G.; Kirillov, Da.; Kirillov, Di.; Kliczewski, St.; Kozela, A.; Kravcikova, M.; Machner, H.; Magiera, A.; Martinska, G.; Messchendorp, J.; Nogga, A.; Parol, W.; Ramazani-Moghaddam-Arani, A.; Roy, B. J.; Sakai, H.; Sekiguchi, K.; Sitnik, I.; Siudak, R.; Skibiński, R.; Sworst, R.; Urban, J.; Witała, H.; Zejma, J.
2014-03-01
One of the most important goals of modern nuclear physics is to contruct nuclear force model which properly describes the experimental data. To develop and test predictions of current models the breakup 1H(overrightarrow d, pp)n reaction was investigated experimentally at 100 and 130 MeV deuteron beam energies. Rich set of data for cross section, vector and tensor analyzing powers was obtained with the use of the SALAD and BINA detectors at KVI and Germanium Wall setup at FZ-Jülich. Results are compared with various theoretical approaches which describe the three-nucleon (3N) system dynamics. For correct description of the cross section data both, three-nucleon force (3NF) and Coulomb force, have to be included into calculations and influence of those ingredients is seizable at specific parts of the phase space. In case of the vector analyzing powers very low sensitivity to any effects beyond nucleon-nucleon interaction was found. At 130 MeV, the Axy data are not correctly described when 3NF models are included into calculations.
Ab initio theories for light nuclei and neutron stars
NASA Astrophysics Data System (ADS)
Gezerlis, Alexandros
2016-09-01
In this talk I will touch upon several features of modern ab initio low-energy nuclear theory. I will start by discussing what ``ab initio'' means in this context. Specifically, I will spend some time going over nucleon-nucleon and three-nucleon interactions and their connections with the underlying theory of Quantum Chromodynamics. I will then show how these interactions are used to describe light nuclei using essentially exact few-body methods. I will then discuss heavier systems, especially those of astrophysical relevance, as well as the methods used to tackle them. This work was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada and the Canada Foundation for Innovation (CFI).
Unified ab initio approaches to nuclear structure and reactions
Navratil, Petr; Quaglioni, Sofia; Hupin, Guillaume; ...
2016-04-13
The description of nuclei starting from the constituent nucleons and the realistic interactions among them has been a long-standing goal in nuclear physics. In addition to the complex nature of the nuclear forces, with two-, three- and possibly higher many-nucleon components, one faces the quantum-mechanical many-nucleon problem governed by an interplay between bound and continuum states. In recent years, significant progress has been made in ab initio nuclear structure and reaction calculations based on input from QCD-employing Hamiltonians constructed within chiral effective field theory. After a brief overview of the field, we focus on ab initio many-body approaches—built upon the no-core shell model—that are capable of simultaneously describing both bound and scattering nuclear states, and present results for resonances in light nuclei, reactions important for astrophysics and fusion research. In particular, we review recent calculations of resonances in the 6He halo nucleus, of five- and six-nucleon scattering, and an investigation of the role of chiral three-nucleon interactions in the structure of 9Be. Further, we discuss applications to the 7Bemore » $${({\\rm{p}},\\gamma )}^{8}{\\rm{B}}$$ radiative capture. Lastly, we highlight our efforts to describe transfer reactions including the 3H$${({\\rm{d}},{\\rm{n}})}^{4}$$He fusion.« less
Ab initio many-body calculations of nucleon- 4He scattering with three-nucleon forces
Hupin, Guillaume; Langhammer, Joachim; Navratil, Petr; ...
2013-11-27
We extend the ab initio no-core shell model/resonating-group method to include three-nucleon (3N) interactions for the description of nucleon-nucleus collisions. We outline the formalism, give algebraic expressions for the 3N-force integration kernels, and discuss computational aspects of two alternative implementations. The extended theoretical framework is then applied to nucleon- 4He elastic scattering using similarity-renormalization-group (SRG)-evolved nucleon-nucleon plus 3N potentials derived from chiral effective field theory. We analyze the convergence properties of the calculated phase shifts and explore their dependence upon the SRG evolution parameter. We include up to six excited states of the 4He target and find significant effects frommore » the inclusion of the chiral 3N force, e.g., it enhances the spin-orbit splitting between the 3/2 – and 1/2 – resonances and leads to an improved agreement with the phase shifts obtained from an accurate R-matrix analysis of the five-nucleon experimental data. As a result, we find remarkably good agreement with measured differential cross sections at various energies below the d+ 3H threshold, while analyzing powers manifest larger deviations from experiment for certain energies and angles.« less
Structure of the Nucleon and its Excitations
NASA Astrophysics Data System (ADS)
Kamleh, Waseem; Leinweber, Derek; Liu, Zhan-wei; Stokes, Finn; Thomas, Anthony; Thomas, Samuel; Wu, Jia-jun
2018-03-01
The structure of the ground state nucleon and its finite-volume excitations are examined from three different perspectives. Using new techniques to extract the relativistic components of the nucleon wave function, the node structure of both the upper and lower components of the nucleon wave function are illustrated. A non-trivial role for gluonic components is manifest. In the second approach, the parity-expanded variational analysis (PEVA) technique is utilised to isolate states at finite momenta, enabling a novel examination of the electric and magnetic form factors of nucleon excitations. Here the magnetic form factors of low-lying odd-parity nucleons are particularly interesting. Finally, the structure of the nucleon spectrum is examined in a Hamiltonian effective field theory analysis incorporating recent lattice-QCD determinations of low-lying two-particle scattering-state energies in the finite volume. The Roper resonance of Nature is observed to originate from multi-particle coupled-channel interactions while the first radial excitation of the nucleon sits much higher at approximately 1.9 GeV.
Chiral Three-Nucleon Interactions in Light Nuclei, Neutron-α Scattering, and Neutron Matter
Lynn, J. E.; Tews, I.; Carlson, Joseph Allen; ...
2016-02-09
Here we present quantum Monte Carlo calculations of light nuclei, neutron- scattering, and neutron matter using local two- and three-nucleon (3N) interactions derived from chiral e effective fi eld theory up to next-to-next-to-leading order (N 2LO). The two undetermined 3N low-energy couplings are fi t to the 4He binding energy and, for the first time, to the spin-orbit splitting in the neutron- P-wave phase shifts. Furthermore, we investigate different choices of local 3N-operator structures and find that chiral interactions at N 2LO are able to simultaneously reproduce the properties of A = 3; 4; 5 systems and of neutron matter,more » in contrast to commonly used phenomenological 3N interactions.« less
Chiral Three-Nucleon Interactions in Light Nuclei, Neutron-α Scattering, and Neutron Matter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lynn, J. E.; Tews, I.; Carlson, Joseph Allen
Here we present quantum Monte Carlo calculations of light nuclei, neutron- scattering, and neutron matter using local two- and three-nucleon (3N) interactions derived from chiral e effective fi eld theory up to next-to-next-to-leading order (N 2LO). The two undetermined 3N low-energy couplings are fi t to the 4He binding energy and, for the first time, to the spin-orbit splitting in the neutron- P-wave phase shifts. Furthermore, we investigate different choices of local 3N-operator structures and find that chiral interactions at N 2LO are able to simultaneously reproduce the properties of A = 3; 4; 5 systems and of neutron matter,more » in contrast to commonly used phenomenological 3N interactions.« less
Tensor Fermi liquid parameters in nuclear matter from chiral effective field theory
NASA Astrophysics Data System (ADS)
Holt, J. W.; Kaiser, N.; Whitehead, T. R.
2018-05-01
We compute from chiral two- and three-body forces the complete quasiparticle interaction in symmetric nuclear matter up to twice nuclear matter saturation density. Second-order perturbative contributions that account for Pauli blocking and medium polarization are included, allowing for an exploration of the full set of central and noncentral operator structures permitted by symmetries and the long-wavelength limit. At the Hartree-Fock level, the next-to-next-to-leading order three-nucleon force contributes to all noncentral interactions, and their strengths grow approximately linearly with the nucleon density up to that of saturated nuclear matter. Three-body forces are shown to enhance the already strong proton-neutron effective tensor interaction, while the corresponding like-particle tensor force remains small. We also find a large isovector cross-vector interaction but small center-of-mass tensor interactions in the isoscalar and isovector channels. The convergence of the expansion of the noncentral quasiparticle interaction in Landau parameters and Legendre polynomials is studied in detail.
Jurgenson, E. D.; Maris, P.; Furnstahl, R. J.; ...
2013-05-13
The similarity renormalization group (SRG) is used to soften interactions for ab initio nuclear structure calculations by decoupling low- and high-energy Hamiltonian matrix elements. The substantial contribution of both initial and SRG-induced three-nucleon forces requires their consistent evolution in a three-particle basis space before applying them to larger nuclei. While, in principle, the evolved Hamiltonians are unitarily equivalent, in practice the need for basis truncation introduces deviations, which must be monitored. Here we present benchmark no-core full configuration calculations with SRG-evolved interactions in p-shell nuclei over a wide range of softening. As a result, these calculations are used to assessmore » convergence properties, extrapolation techniques, and the dependence of energies, including four-body contributions, on the SRG resolution scale.« less
Higgs EFT for 2HDM and beyond.
Bélusca-Maïto, Hermès; Falkowski, Adam; Fontes, Duarte; Romão, Jorge C; Silva, João P
2017-01-01
We discuss the validity of the Standard Model Effective Field Theory (SM EFT) as the low-energy effective theory for the two-Higgs-doublet Model (2HDM). Using the up-to-date Higgs signal strength measurements at the LHC, one can obtain a likelihood function for the Wilson coefficients of dimension-6 operators in the EFT Lagrangian. Given the matching between the 2HDM and the EFT, the constraints on the Wilson coefficients can be translated into constraints on the parameters of the 2HDM Lagrangian. We discuss under which conditions such a procedure correctly reproduces the true limits on the 2HDM. Finally, we employ the SM EFT to identify the pattern of the Higgs boson couplings that are needed to improve the fit to the current Higgs data. To this end, one needs, simultaneously, to increase the top Yukawa coupling, decrease the bottom Yukawa coupling, and induce a new contact interaction of the Higgs boson with gluons. We comment on how these modifications can be realized in the 2HDM extended by new colored particles.
Open sd-shell nuclei from first principles
Jansen, Gustav R.; Signoracci, Angelo J.; Hagen, Gaute; ...
2016-07-05
We extend the ab initio coupled-cluster effective interaction (CCEI) method to open-shell nuclei with protons and neutrons in the valence space, and compute binding energies and excited states of isotopes of neon and magnesium. We employ a nucleon-nucleon and three-nucleon interaction from chiral effective field theory evolved to a lower cutoff via a similarity renormalization group transformation. We find good agreement with experiment for binding energies and spectra, while charge radii of neon isotopes are underestimated. For the deformed nuclei 20Ne and 24Mg we reproduce rotational bands and electric quadrupole transitions within uncertainties estimated from an effective field theory formore » deformed nuclei, thereby demonstrating that collective phenomena in sd-shell nuclei emerge from complex ab initio calculations.« less
Open sd-shell nuclei from first principles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jansen, Gustav R.; Signoracci, Angelo J.; Hagen, Gaute
We extend the ab initio coupled-cluster effective interaction (CCEI) method to open-shell nuclei with protons and neutrons in the valence space, and compute binding energies and excited states of isotopes of neon and magnesium. We employ a nucleon-nucleon and three-nucleon interaction from chiral effective field theory evolved to a lower cutoff via a similarity renormalization group transformation. We find good agreement with experiment for binding energies and spectra, while charge radii of neon isotopes are underestimated. For the deformed nuclei 20Ne and 24Mg we reproduce rotational bands and electric quadrupole transitions within uncertainties estimated from an effective field theory formore » deformed nuclei, thereby demonstrating that collective phenomena in sd-shell nuclei emerge from complex ab initio calculations.« less
The direct detection of boosted dark matter at high energies and PeV events at IceCube
Bhattacharya, A.; Gandhi, R.; Gupta, A.
2015-03-13
We study the possibility of detecting dark matter directly via a small but energetic component that is allowed within present-day constraints. Drawing closely upon the fact that neutral current neutrino nucleon interactions are indistinguishable from DM-nucleon interactions at low energies, we extend this feature to high energies for a small, non-thermal but highly energetic population of DM particle χ, created via the decay of a significantly more massive and long-lived non-thermal relic Φ, which forms the bulk of DM. If χ interacts with nucleons, its cross-section, like the neutrino-nucleus coherent cross-section, can rise sharply with energy leading to deep inelasticmore » scattering, similar to neutral current neutrino-nucleon interactions at high energies. Thus, its direct detection may be possible via cascades in very large neutrino detectors. As a specific example, we apply this notion to the recently reported three ultra-high energy PeV cascade events clustered around 1 – 2 PeV at IceCube (IC). We discuss the features which may help discriminate this scenario from one in which only astrophysical neutrinos constitute the event sample in detectors like IC.« less
Ernst, Alexandra; Blanc, Frédéric; De Seze, Jérôme; Manning, Liliann
2015-01-01
The co-occurrence of autobiographical memory (AM) and episodic future thinking (EFT) impairment has been documented in relapsing-remitting multiple sclerosis (RR-MS) patients. On these bases, we aimed at probing the efficacy of a mental visual imagery (MVI)-based facilitation programme on AM and EFT functioning in the context of a randomised-controlled trial study in RR-MS patients. Using the Autobiographical Interview (AI), 40 patients presenting with an AM/EFT impairment were randomly assigned in three groups: (i) the experimental (n = 17), who followed the MVI programme, (ii) the verbal control (n = 10), who followed a sham verbal programme, and (iii) the stability groups (n = 13), who underwent the AM/EFT test twice, with no intervention in between. AI's second assessment scores showed a significant improvement of AM and EFT performance only for the experimental group, with a long-term robustness of treatment benefits. The control and stability groups' results ruled out nursing and test learning effects as explanations of AM/EFT improvement. These benefits were corroborated by the patients' comments, which indicated an effective MVI strategy transfer to daily life. Our results suggest that the MVI programme tackles a common cognitive process of scene construction present in AM and EFT.
Effects of Episodic Future Thinking and Self-Projection on Children’s Prospective Memory Performance
Kretschmer-Trendowicz, Anett; Ellis, Judith A.; Altgassen, Mareike
2016-01-01
The present study is the first to investigate the benefits of episodic future thinking (EFT) at encoding on prospective memory (PM) in preschool (age: M = 66.34 months, SD = 3.28) and primary school children (age: M = 88.36 months, SD = 3.12). A second aim was to examine if self-projection influences the possible effects of EFT instructions. PM was assessed using a standard PM paradigm in children with a picture-naming task as the ongoing activity in which the PM task was embedded. Further, two first- and two second-order ToM tasks were administered as indicator of children’s self-projection abilities. Forty-one preschoolers and 39 school-aged children were recruited. Half of the participants in each age group were instructed to use EFT as a strategy to encode the PM task, while the others received standard PM instructions. Results revealed a significant age effect, with school-aged children significantly outperforming preschoolers and a significant effect of encoding condition with overall better performance when receiving EFT instructions compared to the standard encoding condition. Even though the interaction between age group and encoding condition was not significant, planned comparisons revealed first evidence that compared to the younger age group, older children’s PM benefitted more from EFT instructions during intention encoding. Moreover, results showed that although self-projection had a significant impact on PM performance, it did not influence the effects of EFT instructions. Overall, results indicate that children can use EFT encoding strategies to improve their PM performance once EFT abilities are sufficiently developed. Further, they provide first evidence that in addition to executive functions, which have already been shown to influence the development of PM across childhood, self-projection seems to be another key mechanism underlying this development. PMID:27355645
Two nucleon systems at m π ~ 450 MeV from lattice QCD
Orginos, Kostas; Parreño, Assumpta; Savage, Martin J.; ...
2015-12-23
Nucleon-nucleon systems are studied with lattice quantum chromodynamics at a pion mass ofmore » $$m_\\pi\\sim 450~{\\rm MeV}$$ in three spatial volumes using $$n_f=2+1$$ flavors of light quarks. At the quark masses employed in this work, the deuteron binding energy is calculated to be $$B_d = 14.4^{+3.2}_{-2.6} ~{\\rm MeV}$$, while the dineutron is bound by $$B_{nn} = 12.5^{+3.0}_{-5.0}~{\\rm MeV}$$. Over the range of energies that are studied, the S-wave scattering phase shifts calculated in the 1S0 and 3S1-3D1 channels are found to be similar to those in nature, and indicate repulsive short-range components of the interactions, consistent with phenomenological nucleon-nucleon interactions. In both channels, the phase shifts are determined at three energies that lie within the radius of convergence of the effective range expansion, allowing for constraints to be placed on the inverse scattering lengths and effective ranges. Thus, the extracted phase shifts allow for matching to nuclear effective field theories, from which low energy counterterms are extracted and issues of convergence are investigated. As part of the analysis, a detailed investigation of the single hadron sector is performed, enabling a precise determination of the violation of the Gell-Mann–Okubo mass relation.« less
NASA Astrophysics Data System (ADS)
Aoki, Sinya
2013-07-01
We review the potential method in lattice QCD, which has recently been proposed to extract nucleon-nucleon interactions via numerical simulations. We focus on the methodology of this approach by emphasizing the strategy of the potential method, the theoretical foundation behind it, and special numerical techniques. We compare the potential method with the standard finite volume method in lattice QCD, in order to make pros and cons of the approach clear. We also present several numerical results for nucleon-nucleon potentials.
Three-Nucleon Forces and Triplet Pairing in Neutron Matter
NASA Astrophysics Data System (ADS)
Papakonstantinou, P.; Clark, J. W.
2017-12-01
The existence of superfluidity of the neutron component in the core of a neutron star, associated specifically with triplet P-wave pairing, is currently an open question that is central to interpretation of the observed cooling curves and other neutron-star observables. Ab initio theoretical calculations aimed at resolving this issue face unique challenges in the relevant high-density domain, which reaches beyond the saturation density of symmetrical nuclear matter. These issues include uncertainties in the three-nucleon (3N) interaction and in the effects of strong short-range correlations—and more generally of in-medium modification of nucleonic self-energies and interactions. A survey of existing solutions of the gap equations in the triplet channel demonstrates that the net impact on the gap magnitude of 3N forces, coupled channels, and mass renormalization shows extreme variation dependent on specific theoretical inputs, in some cases even pointing to the absence of a triplet gap, thus motivating a detailed analysis of competing effects within a well-controlled model. In the present study, we track the effects of the 3N force and in-medium modifications in the representative case of the ^3P_2 channel, based on the Argonne v_{18} two-nucleon (2N) interaction supplemented by 3N interactions of the Urbana IX family. Sensitivity of the results to the input interaction is clearly demonstrated. We point out consistency issues with respect to the simultaneous treatment of 3N forces and in-medium effects, which warrant further investigation. We consider this pilot study as the first step toward a systematic and comprehensive exploration of coupled-channel ^3P F_2 pairing using a broad range of 2N and 3N interactions from the current generation of refined semi-phenomenological models and models derived from chiral effective field theory.
Variational Calculation of the Ground State of Closed-Shell Nuclei Up to $A$ = 40
Lonardoni, Diego; Lovato, Alessandro; Pieper, Steven C.; ...
2017-08-31
Variational calculations of ground-state properties of 4He, 16O and 40Ca are carried out employing realistic phenomenological two- and three-nucleon potentials. The trial wave function includes twoand three-body correlations acting on a product of single-particle determinants. Expectation values are evaluated with a cluster expansion for the spin-isospin dependent correlations considering up to five-body cluster terms. The optimal wave function is obtained by minimizing the energy expectation value over a set of up to 20 parameters by means of a nonlinear optimization library. We present results for the binding energy, charge radius, point density, single-nucleon momentum distribution, charge form factor, and Coulombmore » sum rule. We find that the employed three-nucleon interaction becomes repulsive for A ≥ 16. In 16O the inclusion of such a force provides a better description of the properties of the nucleus. In 40Ca instead, the repulsive behavior of the three-body interaction fails to reproduce experimental data for the charge radius and the charge form factor. We find that the high-momentum region of the momentum distributions, determined by the short-range terms of nuclear correlations, exhibit a universal behavior independent of the particular nucleus. The comparison of the Coulomb sum rules for 4He, 16O, and 40Ca reported in this work will help elucidate in-medium modifications of the nucleon form factors.« less
A survey of the alpha-nucleon interaction
NASA Astrophysics Data System (ADS)
Ali, S.; Ahmad, A. A. Z.; Ferdous, N.
1985-10-01
This paper gives a survey of the alpha-nucleon interaction and then describes experimental work on angular distributions of differential scattering cross sections and polarizations in proton-alpha and neutron-alpha scattering. The phenomenological approach, which includes the study of both local and nonlocal potentials reproducing the experimental alpha-nucleon scattering data, is discussed. Basic studies of the alpha-nucleon interaction attempting to build an interaction between an alpha particle and a nucleon from first principles are then described. The authors then present a critical discussion of the results with some concluding remarks suggesting the direction for further investigation.
Three-body approach to the K-d scattering length in particle basis
NASA Astrophysics Data System (ADS)
Bahaoui, A.; Fayard, C.; Mizutani, T.; Saghai, B.
2002-11-01
We report on the first calculation of the scattering length AK-d based on a relativistic three-body approach where the K¯N coupled channel two-body input amplitudes have been obtained with the chiral SU(3) constraint, but with isospin symmetry breaking effects taken into account. Results are compared with a recent calculation applying a similar set of two-body amplitudes, based on the fixed center approximation, and for which we find significant deviations from the three-body results. Effects of the deuteron D-wave component, pion-nucleon, and hyperon-nucleon interactions are also evaluated.
Three-nucleon force contribution in the distorted-wave theory of (d ,p ) reactions
NASA Astrophysics Data System (ADS)
Timofeyuk, N. K.
2018-05-01
The distorted-wave theory of A (d ,p )B reactions, widely used to analyze experimental data, is based on a Hamiltonian that includes only two-nucleon interactions. However, numerous studies of few-nucleon systems and many modern developments in nuclear structure theory show the importance of the three-nucleon (3 N ) force. The purpose of this paper is to study the contribution of the 3 N force of the simplest possible form to the A (d ,p )B reaction amplitude. This contribution is given by a new term that accounts for the interaction of the neutron and proton in the incoming deuteron with one of the target nucleons. This term involves a new type of nuclear matrix elements containing an infinite number of target excitations in addition to the main part associated with the traditional overlap function between A and B . The nuclear matrix elements are calculated for double-closed shell targets within a mean field theory where target excitations are shown to be equivalent to exchanges between valence and core nucleons. These matrix elements can be readily incorporated into available reaction codes if the 3 N interaction has a spin-independent zero-range form. Distorted-wave calculations are presented for a contact 3 N force with the volume integral fixed by the chiral effective field theory at the next-to-next-to-leading order. For this particular choice, the 3 N contribution is noticeable, especially at high deuteron incident energies. No 3 N effects are seen for incident energies below the Coulomb barrier. The finite range can significantly affect the 3 N contribution to the (d ,p ) cross sections. Finite-range studies require new formal developments and, therefore, their contribution is preliminarily assessed within the plane-wave Born approximation, together with sensitivity to the choice of the deuteron model.
Leading order relativistic hyperon-nucleon interactions in chiral effective field theory
NASA Astrophysics Data System (ADS)
Li, Kai-Wen; Ren, Xiu-Lei; Geng, Li-Sheng; Long, Bing-Wei
2018-01-01
We apply a recently proposed covariant power counting in nucleon-nucleon interactions to study strangeness S=-1 {{\\varLambda }}N-{{\\varSigma }}N interactions in chiral effective field theory. At leading order, Lorentz invariance introduces 12 low energy constants, in contrast to the heavy baryon approach, where only five appear. The Kadyshevsky equation is adopted to resum the potential in order to account for the non-perturbative nature of hyperon-nucleon interactions. A fit to the 36 hyperon-nucleon scattering data points yields {χ }2≃ 16, which is comparable with the sophisticated phenomenological models and the next-to-leading order heavy baryon approach. However, one cannot achieve a simultaneous description of the nucleon-nucleon phase shifts and strangeness S=-1 hyperon-nucleon scattering data at leading order. Supported by the National Natural Science Foundation of China (11375024, 11522539, 11375120), the China Postdoctoral Science Foundation (2016M600845, 2017T100008) and the Fundamental Research Funds for the Central Universities
Secondary neutron-production cross sections from heavy-ion interactions in composite targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heilbronn, L.; Iwata, Y.; Murakami, T.
Secondary neutron-production cross sections have been measured from interactions of 290 MeV/nucleon C and 600 MeV/nucleon Ne in a target composed of simulated Martian regolith and polyethylene, and from 400 MeV/nucleon Ne interactions in wall material from the International Space Station. The data were measured between 5 deg. and 80 deg. in the laboratory. We report the double-differential cross sections, angular distributions, and total neutron-production cross sections from all three systems. The spectra from all three systems exhibit behavior previously reported in other heavy-ion neutron-production experiments, namely, a peak at forward angles near the energy corresponding to the beam velocity,more » with the remaining spectra generated by pre-equilibrium and equilibrium processes. The double-differential cross sections are fitted with a moving-source parametrization. Also reported are the data without corrections for neutron flux attenuation in the target and other intervening materials and for neutron production in nontarget materials near the target position. These uncorrected spectra are compared with SHIELD-HIT and PHITS transport model calculations. The transport model calculations reproduce the spectral shapes well but, on average, underestimate the magnitudes of the cross sections.« less
Manchester, Keith L
2004-01-30
An analysis is made of the rate constants for the reactions involving the interactions of EF-Tu, EF-Ts, GDP, and GTP recently derived by Gromadski et al. [Biochemistry 41 (2002) 162]. Though their measured values appear to allow a reasonable rate of nucleotide exchange sufficient to support rates of protein synthesis in vivo, their data underestimate the thermodynamic barrier involved in nucleotide exchange and therefore cannot be considered definitive. A kinetic scheme consistent with the thermodynamic barrier can be achieved by modification of various rate constants, particularly of those involving the release of EF-Ts from EF-Tu.GTP.EF-Ts, but such constants are markedly different from what are experimentally observed. It thus remains impossible at present satisfactorily to model guanine nucleotide exchange on EF-Tu, catalysed by EF-Ts by a double displacement mechanism, with experimentally derived rate constants. Metabolic control analysis has been applied to determine the degree of flux control of the different steps in the pathway.
Dark matter in the Sun: scattering off electrons vs nucleons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garani, Raghuveer; Palomares-Ruiz, Sergio, E-mail: garani@th.physik.uni-bonn.de, E-mail: sergiopr@ific.uv.es
The annihilation of dark matter (DM) particles accumulated in the Sun could produce a flux of neutrinos, which is potentially detectable with neutrino detectors/telescopes and the DM elastic scattering cross section can be constrained. Although the process of DM capture in astrophysical objects like the Sun is commonly assumed to be due to interactions only with nucleons, there are scenarios in which tree-level DM couplings to quarks are absent, and even if loop-induced interactions with nucleons are allowed, scatterings off electrons could be the dominant capture mechanism. We consider this possibility and study in detail all the ingredients necessary tomore » compute the neutrino production rates from DM annihilations in the Sun (capture, annihilation and evaporation rates) for velocity-independent and isotropic, velocity-dependent and isotropic and momentum-dependent scattering cross sections for DM interactions with electrons and compare them with the results obtained for the case of interactions with nucleons. Moreover, we improve the usual calculations in a number of ways and provide analytical expressions in three appendices. Interestingly, we find that the evaporation mass in the case of interactions with electrons could be below the GeV range, depending on the high-velocity tail of the DM distribution in the Sun, which would open a new mass window for searching for this type of scenarios.« less
3He(γ,pp)n cross sections with tagged photons below the Δ resonance energy
NASA Astrophysics Data System (ADS)
Kolb, N. R.; Feldman, G.; O'rielly, G. V.; Pywell, R. E.; Skopik, D. M.; Hackett, E. D.; Quraan, M. A.; Rodning, N. L.
1996-11-01
Cross sections have been measured for the 3He(γ,pp)n reaction with tagged photons in the range Eγ =161-208 MeV using the Saskatchewan-Alberta Large Acceptance Detector (SALAD). The protons were detected over a range of polar angles of 40°-140° and azimuthal angles of 0°-360° with an energy threshold of 40 MeV. Comparisons are made with a microscopic calculation which includes one-, two-, and three-nucleon absorption mechanisms. One- and two-nucleon processes, including final-state interactions, are unable to account for the measured cross sections. The addition of three-nucleon absorption diagrams gives roughly the right strength, but the distribution in phase space is in disagreement with the data.
Gaesser, Amy H; Karan, Orv C
2017-02-01
The objective of this pilot study was to compare the efficacy of Emotional Freedom Techniques (EFT) with that of Cognitive-Behavioral Therapy (CBT) in reducing adolescent anxiety. Randomized controlled study. This study took place in 10 schools (8 public/2 private; 4 high schools/6 middle schools) in 2 northeastern states in the United States. Sixty-three high-ability students in grades 6-12, ages 10-18 years, who scored in the moderate to high ranges for anxiety on the Revised Children's Manifest Anxiety Scale-2 (RCMAS-2) were randomly assigned to CBT (n = 21), EFT (n = 21), or waitlist control (n = 21) intervention groups. CBT is the gold standard of anxiety treatment for adolescent anxiety. EFT is an evidence-based treatment for anxiety that incorporates acupoint stimulation. Students assigned to the CBT or EFT treatment groups received three individual sessions of the identified protocols from trained graduate counseling, psychology, or social work students enrolled at a large northeastern research university. The RCMAS-2 was used to assess preintervention and postintervention anxiety levels in participants. EFT participants (n = 20; M = 52.16, SD = 9.23) showed significant reduction in anxiety levels compared with the waitlist control group (n = 21; M = 57.93, SD = 6.02) (p = 0.005, d = 0.74, 95% CI [-9.76, -1.77]) with a moderate to large effect size. CBT participants (n = 21; M = 54.82, SD = 5.81) showed reduction in anxiety but did not differ significantly from the EFT (p = 0.18, d = 0.34; 95% CI [-6.61, 1.30]) or control (p = 0.12, d = 0.53, 95% CI [-7.06, .84]). EFT is an efficacious intervention to significantly reduce anxiety for high-ability adolescents.
Investigations of Few-Nucleon System Dynamics in Medium Energy Domain
NASA Astrophysics Data System (ADS)
Ciepał, I.; Kłos, B.; Kistryn, St.; Stephan, E.; Biegun, A.; Bodek, K.; Deltuva, A.; Epelbaum, E.; Eslami-Kalantari, M.; Fonseca, A. C.; Golak, J.; Jha, V.; Kalantar-Nayestanaki, N.; Kamada, H.; Khatri, G.; Kirillov, Da.; Kirillov, Di.; Kliczewski, St.; Kozela, A.; Kravcikova, M.; Machner, H.; Magiera, A.; Martinska, G.; Messchendorp, J.; Nogga, A.; Parol, W.; Ramazani-Moghaddam-Arani, A.; Roy, B. J.; Sakai, H.; Sekiguchi, K.; Sitnik, I.; Siudak, R.; Skibiński, R.; Sworst, R.; Urban, J.; Witała, H.; Wrońska, A.; Zejma, J.
2013-08-01
Precise and large set of cross sections, vector A x , A y and tensor A xx , A xy , A yy analyzing powers for the 1 H( d, pp) n breakup reactions were measured at 100 and 130 MeV deuteron beam energies with the use of the SALAD and BINA detectors at KVI and Germanium Wall setup at FZ-Jülich. Results are compared with various theoretical approaches which model the three-nucleon (3N) system dynamics. The calculations are based on different two-nucleon (2N) potentials which can be combined with models of the three-nucleon force (3NF) and other pieces of the dynamics can also be included like the Coulomb interaction and relativistic effects. The cross sections data reveal seizable 3NF and Coulomb force influence. In case of analyzing powers very low sensitivity to the effects was found and the data are well describe by 2N models only. At 130 MeV for A xy serious disagreements appear when 3NF models are included into calculations.
Strangeness S =-1 hyperon-nucleon interactions: Chiral effective field theory versus lattice QCD
NASA Astrophysics Data System (ADS)
Song, Jing; Li, Kai-Wen; Geng, Li-Sheng
2018-06-01
Hyperon-nucleon interactions serve as basic inputs to studies of hypernuclear physics and dense (neutron) stars. Unfortunately, a precise understanding of these important quantities has lagged far behind that of the nucleon-nucleon interaction due to lack of high-precision experimental data. Historically, hyperon-nucleon interactions are either formulated in quark models or meson exchange models. In recent years, lattice QCD simulations and chiral effective field theory approaches start to offer new insights from first principles. In the present work, we contrast the state-of-the-art lattice QCD simulations with the latest chiral hyperon-nucleon forces and show that the leading order relativistic chiral results can already describe the lattice QCD data reasonably well. Given the fact that the lattice QCD simulations are performed with pion masses ranging from the (almost) physical point to 700 MeV, such studies provide a useful check on both the chiral effective field theory approaches as well as lattice QCD simulations. Nevertheless more precise lattice QCD simulations are eagerly needed to refine our understanding of hyperon-nucleon interactions.
A Lagrangian effective field theory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vlah, Zvonimir; White, Martin; Aviles, Alejandro
We have continued the development of Lagrangian, cosmological perturbation theory for the low-order correlators of the matter density field. We provide a new route to understanding how the effective field theory (EFT) of large-scale structure can be formulated in the Lagrandian framework and a new resummation scheme, comparing our results to earlier work and to a series of high-resolution N-body simulations in both Fourier and configuration space. The `new' terms arising from EFT serve to tame the dependence of perturbation theory on small-scale physics and improve agreement with simulations (though with an additional free parameter). We find that all ofmore » our models fare well on scales larger than about two to three times the non-linear scale, but fail as the non-linear scale is approached. This is slightly less reach than has been seen previously. At low redshift the Lagrangian model fares as well as EFT in its Eulerian formulation, but at higher z the Eulerian EFT fits the data to smaller scales than resummed, Lagrangian EFT. Furthermore, all the perturbative models fare better than linear theory.« less
A Lagrangian effective field theory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vlah, Zvonimir; White, Martin; Aviles, Alejandro, E-mail: zvlah@stanford.edu, E-mail: mwhite@berkeley.edu, E-mail: aviles@berkeley.edu
We have continued the development of Lagrangian, cosmological perturbation theory for the low-order correlators of the matter density field. We provide a new route to understanding how the effective field theory (EFT) of large-scale structure can be formulated in the Lagrandian framework and a new resummation scheme, comparing our results to earlier work and to a series of high-resolution N-body simulations in both Fourier and configuration space. The 'new' terms arising from EFT serve to tame the dependence of perturbation theory on small-scale physics and improve agreement with simulations (though with an additional free parameter). We find that all ofmore » our models fare well on scales larger than about two to three times the non-linear scale, but fail as the non-linear scale is approached. This is slightly less reach than has been seen previously. At low redshift the Lagrangian model fares as well as EFT in its Eulerian formulation, but at higher z the Eulerian EFT fits the data to smaller scales than resummed, Lagrangian EFT. All the perturbative models fare better than linear theory.« less
A Lagrangian effective field theory
Vlah, Zvonimir; White, Martin; Aviles, Alejandro
2015-09-02
We have continued the development of Lagrangian, cosmological perturbation theory for the low-order correlators of the matter density field. We provide a new route to understanding how the effective field theory (EFT) of large-scale structure can be formulated in the Lagrandian framework and a new resummation scheme, comparing our results to earlier work and to a series of high-resolution N-body simulations in both Fourier and configuration space. The `new' terms arising from EFT serve to tame the dependence of perturbation theory on small-scale physics and improve agreement with simulations (though with an additional free parameter). We find that all ofmore » our models fare well on scales larger than about two to three times the non-linear scale, but fail as the non-linear scale is approached. This is slightly less reach than has been seen previously. At low redshift the Lagrangian model fares as well as EFT in its Eulerian formulation, but at higher z the Eulerian EFT fits the data to smaller scales than resummed, Lagrangian EFT. Furthermore, all the perturbative models fare better than linear theory.« less
30 CFR 1218.51 - How to make payments.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., General § 1218.51 How to make payments. (a) Definitions. ACH—Automated Clearing House. A type of EFT using... (three-alpha and nine-numeric characters). Pay.gov—A type of EFT using the ACH network that is initiated...) Federal Reserve check. (5) You must include your payor code on all payments. (6) You must pay in U.S...
Analyzing the Fierz rearrangement freedom for local chiral two-nucleon potentials
NASA Astrophysics Data System (ADS)
Huth, L.; Tews, I.; Lynn, J. E.; Schwenk, A.
2017-11-01
Chiral effective field theory is a framework to derive systematic nuclear interactions. It is based on the symmetries of quantum chromodynamics and includes long-range pion physics explicitly, while shorter-range physics is expanded in a general operator basis. The number of low-energy couplings at a particular order in the expansion can be reduced by exploiting the fact that nucleons are fermions and therefore obey the Pauli exclusion principle. The antisymmetry permits the selection of a subset of the allowed contact operators at a given order. When local regulators are used for these short-range interactions, however, this "Fierz rearrangement freedom" is violated. In this paper, we investigate the impact of this violation at leading order (LO) in the chiral expansion. We construct LO and next-to-leading order (NLO) potentials for all possible LO-operator pairs and study their reproduction of phase shifts, the 4He ground-state energy, and the neutron-matter energy at different densities. We demonstrate that the Fierz rearrangement freedom is partially restored at NLO where subleading contact interactions enter. We also discuss implications for local chiral three-nucleon interactions.
Origin of fine structure of the giant dipole resonance in s d -shell nuclei
NASA Astrophysics Data System (ADS)
Fearick, R. W.; Erler, B.; Matsubara, H.; von Neumann-Cosel, P.; Richter, A.; Roth, R.; Tamii, A.
2018-04-01
A set of high-resolution zero-degree inelastic proton scattering data on 24Mg, 28Si, 32S, and 40Ca provides new insight into the long-standing puzzle of the origin of fragmentation of the giant dipole resonance (GDR) in s d -shell nuclei. Understanding is achieved by comparison with random phase approximation calculations for deformed nuclei using for the first time a realistic nucleon-nucleon interaction derived from the Argonne V18 potential with the unitary correlation operator method and supplemented by a phenomenological three-nucleon contact interaction. A wavelet analysis allows one to extract significant scales both in the data and calculations characterizing the fine structure of the GDR. The fair agreement for scales in the range of a few hundred keV supports the surmise that the fine structure arises from ground-state deformation driven by α clustering.
Deriving the nuclear shell model from first principles
NASA Astrophysics Data System (ADS)
Barrett, Bruce R.; Dikmen, Erdal; Vary, James P.; Maris, Pieter; Shirokov, Andrey M.; Lisetskiy, Alexander F.
2014-09-01
The results of an 18-nucleon No Core Shell Model calculation, performed in a large basis space using a bare, soft NN interaction, can be projected into the 0 ℏω space, i.e., the sd -shell. Because the 16 nucleons in the 16O core are frozen in the 0 ℏω space, all the correlations of the 18-nucleon system are captured by the two valence, sd -shell nucleons. By the projection, we obtain microscopically the sd -shell 2-body effective interactions, the core energy and the sd -shell s.p. energies. Thus, the input for standard shell-model calculations can be determined microscopically by this approach. If the same procedure is then applied to 19-nucleon systems, the sd -shell 3-body effective interactions can also be obtained, indicating the importance of these 3-body effective interactions relative to the 2-body effective interactions. Applications to A = 19 and heavier nuclei with different intrinsic NN interactions will be presented and discussed. The results of an 18-nucleon No Core Shell Model calculation, performed in a large basis space using a bare, soft NN interaction, can be projected into the 0 ℏω space, i.e., the sd -shell. Because the 16 nucleons in the 16O core are frozen in the 0 ℏω space, all the correlations of the 18-nucleon system are captured by the two valence, sd -shell nucleons. By the projection, we obtain microscopically the sd -shell 2-body effective interactions, the core energy and the sd -shell s.p. energies. Thus, the input for standard shell-model calculations can be determined microscopically by this approach. If the same procedure is then applied to 19-nucleon systems, the sd -shell 3-body effective interactions can also be obtained, indicating the importance of these 3-body effective interactions relative to the 2-body effective interactions. Applications to A = 19 and heavier nuclei with different intrinsic NN interactions will be presented and discussed. Supported by the US NSF under Grant No. 0854912, the US DOE under Grants Nos. DESC0008485 and DE-FG02-87ER40371, the Higher Education Council of Turkey(YOK), and the Ministry of Education and Science of Russian Fed. under contracts P521 and 14.v37.21.1297.
Reentrant behavior in the nearest-neighbor Ising antiferromagnet in a magnetic field
NASA Astrophysics Data System (ADS)
Neto, Minos A.; de Sousa, J. Ricardo
2004-12-01
Motived by the H-T phase diagram in the bcc Ising antiferromagnetic with nearest-neighbor interactions obtained by Monte Carlo simulation [Landau, Phys. Rev. B 16, 4164 (1977)] that shows a reentrant behavior at low temperature, with two critical temperatures in magnetic field about 2% greater than the critical value Hc=8J , we apply the effective field renormalization group (EFRG) approach in this model on three-dimensional lattices (simple cubic-sc and body centered cubic-bcc). We find that the critical curve TN(H) exhibits a maximum point around of H≃Hc only in the bcc lattice case. We also discuss the critical behavior by the effective field theory in clusters with one (EFT-1) and two (EFT-2) spins, and a reentrant behavior is observed for the sc and bcc lattices. We have compared our results of EFRG in the bcc lattice with Monte Carlo and series expansion, and we observe a good accordance between the methods.
Cloning and characterization of EF-Tu and EF-Ts from Pseudomonas aeruginosa.
Palmer, Stephanie O; Rangel, Edna Y; Montalvo, Alberto E; Tran, Alexis T; Ferguson, Kate C; Bullard, James M
2013-01-01
We have cloned genes encoding elongation factors EF-Tu and EF-Ts from Pseudomonas aeruginosa and expressed and purified the proteins to greater than 95% homogeneity. Sequence analysis indicated that P. aeruginosa EF-Tu and EF-Ts are 84% and 55% identical to E. coli counterparts, respectively. P. aeruginosa EF-Tu was active when assayed in GDP exchange assays. Kinetic parameters for the interaction of EF-Tu with GDP in the absence of EF-Ts were observed to be K M = 33 μM, k cat (obs) = 0.003 s(-1), and the specificity constant k cat (obs)/K M was 0.1 × 10(-3) s(-1) μM(-1). In the presence of EF-Ts, these values were shifted to K M = 2 μM, k cat (obs) = 0.005 s(-1), and the specificity constant k(cat)(obs)/K M was 2.5 × 10(-3) s(-1) μM(-1). The equilibrium dissociation constants governing the binding of EF-Tu to GDP (K GDP) were 30-75 nM and to GTP (K GTP) were 125-200 nM. EF-Ts stimulated the exchange of GDP by EF-Tu 10-fold. P. aeruginosa EF-Tu was active in forming a ternary complex with GTP and aminoacylated tRNA and was functional in poly(U)-dependent binding of Phe-tRNA(Phe) at the A-site of P. aeruginosa ribosomes. P. aeruginosa EF-Tu was active in poly(U)-programmed polyphenylalanine protein synthesis system composed of all P. aeruginosa components.
Beyond BCS pairing in high-density neutron matter
NASA Astrophysics Data System (ADS)
Rios, A.; Ding, D.; Dussan, H.; Dickhoff, W. H.; Witte, S. J.; Polls, A.
2018-01-01
Pairing gaps in neutron matter need to be computed in a wide range of densities to address open questions in neutron star phenomenology. Traditionally, the Bardeen-Cooper-Schrieffer approach has been used to compute gaps from bare nucleon-nucleon interactions. Here, we incorporate the influence of short- and long-range correlations into pairing properties. Short-range correlations are treated including the appropriate fragmentation of single-particle states, and they suppress the gaps substantially. Long-range correlations dress the pairing interaction via density and spin modes, and provide a relatively small correction. We use three different interactions as a starting point to control for any systematic effects. Results are relevant for neutron-star cooling scenarios, in particular in view of the recent observational data on Cassiopeia A.
QCD structure of nuclear interactions
NASA Astrophysics Data System (ADS)
Granados, Carlos G.
The research presented in this dissertation investigated selected processes involving baryons and nuclei in hard scattering reactions. These processes are characterized by the production of particles with large energies and transverse momenta. Through these processes, this work explored both, the constituent (quark) structure of baryons (specifically nucleons and Delta-Isobars), and the mechanisms through which the interactions between these constituents ultimately control the selected reactions. The first of such reactions is the hard nucleon-nucleon elastic scattering, which was studied here considering the quark exchange between the nucleons to be the dominant mechanism of interaction in the constituent picture. In particular, it was found that an angular asymmetry exhibited by proton-neutron elastic scattering data is explained within this framework if a quark-diquark picture dominates the nucleon's structure instead of a more traditional SU(6) three quarks picture. The latter yields an asymmetry around 90o center of mass scattering with a sign opposite to what is experimentally observed. The second process is the hard breakup by a photon of a nucleon-nucleon system in light nuclei. Proton-proton (pp) and proton-neutron (pn) breakup in 3He, and DeltaDelta-isobars production in deuteron breakup were analyzed in the hard rescattering model (HRM), which in conjunction with the quark interchange mechanism provides a Quantum Chromodynamics (QCD) description of the reaction. Through the HRM, cross sections for both channels in 3He photodisintegration were computed without the need of a fitting parameter. The results presented here for pp breakup show excellent agreement with recent experimental data. In DeltaDelta-isobars production in deuteron breakup, HRM angular distributions for the two DeltaDelta channels were compared to the pn channel and to each other. An important prediction fromthis study is that the Delta++Delta- channel consistently dominates Delta+Delta0, which is in contrast with models that unlike the HRM consider a DeltaDelta system in the initial state of the interaction. For such models both channels should have the same strength. These results are important in developing a QCD description of the atomic nucleus.
The chiral quark condensate and pion decay constant in nuclear matter at next-to-leading order
NASA Astrophysics Data System (ADS)
Lacour, A.; Oller, J. A.; Meißner, U.-G.
2010-12-01
Making use of the recently developed chiral power counting for the physics of nuclear matter (Oller et al 2010 J. Phys. G: Nucl. Part. Phys. 37 015106, Lacour et al Ann. Phys. at press), we evaluate the in-medium chiral quark condensate up to next-to-leading order for both symmetric nuclear matter and neutron matter. Our calculation includes the full in-medium iteration of the leading order local and one-pion exchange nucleon-nucleon interactions. Interestingly, we find a cancellation between the contributions stemming from the quark mass dependence of the nucleon mass appearing in the in-medium nucleon-nucleon interactions. Only the contributions originating from the explicit quark mass dependence of the pion mass survive. This cancellation is the reason of previous observations concerning the dominant role of the long-range pion contributions and the suppression of short-range nucleon-nucleon interactions. We find that the linear density contribution to the in-medium chiral quark condensate is only slightly modified for pure neutron matter by the nucleon-nucleon interactions. For symmetric nuclear matter, the in-medium corrections are larger, although smaller compared to other approaches due to the full iteration of the lowest order nucleon-nucleon tree-level amplitudes. Our calculation satisfies the Hellmann-Feynman theorem to the order worked out. Also we address the problem of calculating the leading in-medium corrections to the pion decay constant. We find that there are no extra in-medium corrections that violate the Gell-Mann-Oakes-Renner relation up to next-to-leading order.
Nucleon interaction data bases for background estimates
NASA Technical Reports Server (NTRS)
Wilson, John W.; Townsend, Lawrence W.
1989-01-01
Nucleon interaction data bases available in the open literature are examined for potential use in a recently developed nucleon transport code. Particular attention is given to secondary particle penetration and the multiple charged ion products. A brief description of the transport algorithm is given.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Golak, J.; Skibinski, R.; Topolnicki, K.
Here, we solve three-nucleon Faddeev equations with nucleon-nucleon and three-nucleon forces derived consistently in the framework of chiral perturbation theory at next-to-next-to-next-to-leading order in the chiral expansion. In this first investigation we include only matrix elements of the three-nucleon force for partial waves with the total two-nucleon (three-nucleon) angular momenta up to 3 (5/2). Low-energy neutron-deuteron elastic scattering and deuteron breakup reaction are studied. Emphasis is put on A y puzzle in elastic scattering and cross sections in symmetric-space-star and neutron-neutron quasi-free-scattering breakup configurations, for which large discrepancies between data and theory have been reported.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Babenko, V. A.; Petrov, N. M., E-mail: pet2@ukr.net
2016-01-15
The relation between quantities that characterize the pion–nucleon and nucleon–nucleon interactions is studied with allowance for the fact that, at low energies, nuclear forces in nucleon–nucleon systems are mediated predominantly by one-pion exchange. On the basis of the values currently recommended for the low-energy parameters of the proton–proton interaction, the charged pion–nucleon coupling constant is evaluated at g{sub π}{sup 2}±/4π = 14.55(13). This value is in perfect agreement with the experimental value of g{sub π}{sup 2}±/4π = 14.52(26) found by the Uppsala Neutron Research Group. At the same time, the value obtained for the charged pion–nucleon coupling constant differs sizablymore » from the value of the pion–nucleon coupling constant for neutral pions, which is g{sub π}{sup 2} 0/4π = 13.55(13). This is indicative of a substantial charge dependence of the coupling constant.« less
Katlandur, Hüseyin; Ulucan, Şeref; Özdil, Hüseyin; Keser, Ahmet; Kaya, Zeynettin; Özbek, Kerem; Ülgen, M Sıddık
2016-11-01
The association between epicardial fat thickness (EFT) and positive exercise test results for the diagnosis of coronary artery diseases (CAD) has yet to be evaluated. This study assessed the predictive value of EFT for CAD on the angiographs of patients with positive exercise tests. A total of 91 subjects were chosen consecutively from stable angina pectoris patients who were referred for coronary angiography due to a positive exercise test result. The EFT measures were obtained by echocardiographic parasternal long-axis views on the free wall of the right ventricle at end-systole of three cardiac cycles. Gensini scores were calculated by a conventional coronary angiography technique using a calculation method previously defined. Receiver operator characteristic (ROC) curve analysis revealed a 0.65 cm (95% confidence interval: 0.628, 0.832, p < 0.001) area under the curve with 74.3% sensitivity and 62.3% specificity at the cut-off value of EFT for the prediction of critical coronary artery stenosis. Following ROC curve analysis, two groups were defined according to EFT cut-off value (groups 1 and 2). The severe coronary stenosis ratio was significantly higher in group 2 compared to group 1 (31.9 % vs. 11%, p < 0.001) and Gensini scores were significantly higher in group 2 (6.3 ± 13.3 vs. 16.5 ± 17.9; p < 0.001). There was no significant correlation between Gensini scores and EFT in group 1 (r = 0.093, p = 0.549), but there was a strong significant correlation in group 2 (r = 0.730, p < 0.001). Linear multivariate regression analysis revealed that EFT (> 0.65 cm) was the only independent risk factor for critical coronary artery stenosis (β = 0.451, p < 0.001). EFT was significantly correlated with the severity and prevalence of coronary artery disease in positive exercise test patients.
Can Ab Initio Theory Explain the Phenomenon of Parity Inversion in Be 11 ?
Calci, Angelo; Navratil, Petr; Roth, Robert; ...
2016-12-09
The weakly bound exotic 11Be nucleus, famous for its ground-state parity inversion and distinct n + 10Be halo structure, is investigated from first principles using chiral two- and three-nucleon forces. An explicit treatment of continuum effects is found to be indispensable. We study the sensitivity of the 11Be spectrum to the details of the three-nucleon force and demonstrate that only certain chiral interactions are capable of reproducing the parity inversion. With such interactions, the extremely large E1 transition between the bound states is reproduced. We compare our photodisintegration calculations to conflicting experimental data and predict a distinct dip around themore » 3/2 – 1 resonance energy. Finally, we predict low-lying 3/2 + and 9/2 + resonances that are not or not sufficiently measured in experiments.« less
Nuclear structure research at the Triangle Universities Nuclear Laboratory
NASA Astrophysics Data System (ADS)
Mitchell, G. E.
1992-10-01
Studies of fundamental symmetries by the TRIPLE collaboration using the unique capabilities at LAMTF have found unexpected systematics in the parity-violating amplitudes for epithermal-neutron scattering. Tests to lower the present limits on time-reversal-invariance violation in the strong interaction are being made at in experiments on the scattering of polarized fast neutrons from aligned holmium targets. Studies of few-nucleon systems have received increasing emphasis over the past year, involving a broad program for testing the low- to medium-energy internucleon interactions, from the tensor component in n-p scattering and the n-n scattering lengths, through three-nucleon systems and the alpha particle, on up to Be-8. Of particular interest are three-nucleon systems, both in elastic scattering and in three-body breakup. Beam requirements range from production of intense and highly-polarized neutron beams to tensor-polarized beams for measurements at both very low energies (25-80 keV) and at tandem energies for definitive measurements of D-state components of the triton, He-3, and He-4 obtained from transfer reactions. The program in nuclear astrophysics expanded during 1991-1992. Several facets of the nuclear many-body problem and of excitation mechanisms of the nucleus are being elucidated, including measurements and analyses to elucidate the neutron-nucleus elastic-scattering interaction over a wide range of nuclei and energies. Several projects involved developments in electronuclear physics, instrumentation, RF-transition units, and low-temperature bolometric particle detectors.
Low-energy neutron-deuteron reactions with N 3LO chiral forces
Golak, J.; Skibinski, R.; Topolnicki, K.; ...
2014-11-27
Here, we solve three-nucleon Faddeev equations with nucleon-nucleon and three-nucleon forces derived consistently in the framework of chiral perturbation theory at next-to-next-to-next-to-leading order in the chiral expansion. In this first investigation we include only matrix elements of the three-nucleon force for partial waves with the total two-nucleon (three-nucleon) angular momenta up to 3 (5/2). Low-energy neutron-deuteron elastic scattering and deuteron breakup reaction are studied. Emphasis is put on A y puzzle in elastic scattering and cross sections in symmetric-space-star and neutron-neutron quasi-free-scattering breakup configurations, for which large discrepancies between data and theory have been reported.
Sebastian, Brenda; Nelms, Jerrod
Over the past two decades, growing numbers of clinicians have been utilizing emotional freedom techniques (EFT) in the treatment of posttraumatic stress disorder (PTSD), anxiety, and depression. Randomized controlled trials (RCTs) have shown encouraging outcomes for all three conditions. To assess the efficacy of EFT in treating PTSD by conducting a meta-analysis of existing RCTs. A systematic review of databases was undertaken to identify RCTs investigating EFT in the treatment of PTSD. The RCTs were evaluated for quality using evidence-based standards published by the American Psychological Association Division 12 Task Force on Empirically Validated Therapies. Those meeting the criteria were assessed using a meta-analysis that synthesized the data to determine effect sizes. While uncontrolled outcome studies were excluded, they were examined for clinical implications of treatment that can extend knowledge of this condition. Seven randomized controlled trials were found to meet the criteria and were included in the meta-analysis. A large treatment effect was found, with a weighted Cohen׳s d = 2.96 (95% CI: 1.96-3.97, P < .001) for the studies that compared EFT to usual care or a waitlist. No treatment effect differences were found in studies comparing EFT to other evidence-based therapies such as eye movement desensitization and reprocessing (EMDR; 1 study) and cognitive behavior therapy (CBT; 1 study). The analysis of existing studies showed that a series of 4-10 EFT sessions is an efficacious treatment for PTSD with a variety of populations. The studies examined reported no adverse effects from EFT interventions and showed that it can be used both on a self-help basis and as a primary evidence-based treatment for PTSD. Copyright © 2017 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scopel, Stefano; Yu, Hyeonhye, E-mail: scopel@sogang.ac.kr, E-mail: skyh2yu@gmail.com
We discuss strategies to make inferences on the thermal relic abundance of a Weakly Interacting Massive Particle (WIMP) when the same effective dimension-six operator that explains an experimental excess in direct detection is assumed to drive decoupling at freeze-out, and apply them to the explicit scenario of WIMP inelastic up-scattering with spin-dependent couplings to protons (proton-philic Spin-dependent Inelastic Dark Matter, pSIDM), a phenomenological set-up containing two Dark Matter (DM) particles χ{sub 1} and χ{sub 2} with masses m {sub χ}= m {sub χ{sub 1}} and m {sub χ{sub 2}}= m {sub χ}+δ that we have shown in a previous papermore » to explain the DAMA effect in compliance with the constraints from other detectors. We also update experimental constraints on pSIDM, extend the analysis to the most general spin-dependent momentum-dependent interactions allowed by non-relativistic Effective Field Theory (EFT), and consider for the WIMP velocity distribution in our Galaxy f ( v ) both a halo-independent approach and a standard Maxwellian. Under these conditions we find that the DAMA effect can be explained in terms of the particle χ{sub 1} in compliance with all the other constraints for all the analyzed EFT couplings and also for a Maxwellian f ( v ). As far as the relic abundance is concerned, we show that the problem of calculating it by using direct detection data to fix the model parameters is affected by a strong sensitivity on f ( v ) and by the degeneracy between the WIMP local density ρ{sub χ} and the WIMP-nucleon scattering cross section, since ρ{sub χ} must be rescaled with respect to the observed DM density in the neighborhood of the Sun when the calculated relic density Ω is smaller than the observed one Ω{sub 0}. As a consequence, a DM direct detection experiment is not directly sensitive to the physical cut-off scale of the EFT, but on some dimensional combination that does not depend on the actual value of Ω. However, such degeneracy can be used to develop a consistency test on the possibility that the WIMP is a thermal relic in the first place. When we apply it to the pSIDM scenario we find that only a WIMP with the standard spin-dependent interaction O=χ-bar {sub 1γ}{sup μ}γ{sup 5χ{sub 2}} q-bar γ{sub μ}γ{sup 5} q + h.c. with quarks can be a thermal relic for, approximately, 10 GeV\\;≲ m {sub χ}≲ 16 GeV, 17 keV\\;≲ δ≲ 28 keV, and a large uncertainty on Ω, 6× 10{sup −7}Ω{sub 0≲} Ω ≲ Ω{sub 0}. In order for the scenario to work the WIMP galactic velocity distribution must depart from a Maxwellian. Moreover, all the χ{sub 2} states must have already decayed today, and this requires some additional mechanism besides that provided by the O operator.« less
Nucleon decay and atmospheric neutrinos in the Mont Blanc experiment
NASA Technical Reports Server (NTRS)
Battistoni, G.; Bellotti, E.; Bologne, G.; Campana, P.; Castagnoli, C.; Chiarella, V.; Ciocio, A.; Cundy, D. C.; Dettorepiazzoli, B.; Fiorini, E.
1985-01-01
In the NUSEX experiment, during 2.8 years of operation, 31 fully contained events have been collected; 3 among them are nucleon decay candidates, while the others have been attributed to upsilon interactions. Limits on nucleon lifetime and determinations of upsilon interaction rates are presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henning, Brian; Lu, Xiaochuan; Murayama, Hitoshi
Here, we present a practical three-step procedure of using the Standard Model effective field theory (SM EFT) to connect ultraviolet (UV) models of new physics with weak scale precision observables. With this procedure, one can interpret precision measurements as constraints on a given UV model. We give a detailed explanation for calculating the effective action up to one-loop order in a manifestly gauge covariant fashion. This covariant derivative expansion method dramatically simplifies the process of matching a UV model with the SM EFT, and also makes available a universal formalism that is easy to use for a variety of UVmore » models. A few general aspects of RG running effects and choosing operator bases are discussed. Finally, we provide mapping results between the bosonic sector of the SM EFT and a complete set of precision electroweak and Higgs observables to which present and near future experiments are sensitive. Many results and tools which should prove useful to those wishing to use the SM EFT are detailed in several appendices.« less
Secondary neutron-production cross sections from heavy-ioninteractions in composite targets.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heilbronn, L.; Iwata, Y.; Iwase,H.
Secondary neutron-production cross-sections have been measured from interactions of 290 MeV/nucleon C and 600 MeV/nucleon Ne in a target composed of simulated Martian regolith and polyethylene, and from 400 MeV/nucleon Ne interactions in wall material from the International Space Station. The data were measured between 5 and 80 deg in the laboratory. We report the double-differential cross sections, angular distributions, and total neutron-production cross sections from all three systems. The spectra from all three systems exhibit behavior previously reported in other heavy-ion, neutron production experiments; namely, a peak at forward angles near the energy corresponding to the beam velocity, withmore » the remaining spectra generated by pre-equilibrium and equilibrium processes. The double differential cross sections are fitted with a moving-source parameterization. Also reported are the data without corrections for neutron flux attenuation in the target and other intervening materials, and for neutron production in non-target materials near the target position. These uncorrected spectra are compared with SHIELD-HIT and PHITS transport model calculations. The transport model calculations reproduce the spectral shapes well, but, on average, underestimate the magnitudes of the cross sections.« less
A Review of the Research in Emotionally Focused Therapy for Couples.
Wiebe, Stephanie A; Johnson, Susan M
2016-09-01
Emotionally Focused Therapy for Couples (EFT) is a brief evidence-based couple therapy based in attachment theory. Since the development of EFT, efficacy and effectiveness research has accumulated to address a range of couple concerns. EFT meets or exceeds the guidelines for classification as an evidence-based couple therapy outlined for couple and family research. Furthermore, EFT researchers have examined the process of change and predictors of outcome in EFT. Future research in EFT will continue to examine the process of change in EFT and test the efficacy and effectiveness of EFT in new applications and for couples of diverse backgrounds and concerns. © 2016 Family Process Institute.
Structure of Ni 78 from First-Principles Computations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hagen, Gaute; Univ. of Tennessee, Knoxville, TN; Jansen, Gustav R.
Doubly magic nuclei have a simple structure and are the cornerstones for entire regions of the nuclear chart. Theoretical insights into the supposedly doubly magic 78Ni and its neighbors are challenging because of the extreme neutron-to-proton ratio and the proximity of the continuum. In this study, we predict the J π = 2more » $$+\\atop{1}$$ state in 78Ni from a correlation with the J π = 2$$+\\atop{1}$$ state in 48Ca using chiral nucleon-nucleon and three-nucleon interactions. Our results confirm that 78Ni is doubly magic, and the predicted low-lying states of 79,80Ni open the way for shell-model studies of many more rare isotopes.« less
Structure of Ni 78 from First-Principles Computations
Hagen, Gaute; Univ. of Tennessee, Knoxville, TN; Jansen, Gustav R.; ...
2016-10-17
Doubly magic nuclei have a simple structure and are the cornerstones for entire regions of the nuclear chart. Theoretical insights into the supposedly doubly magic 78Ni and its neighbors are challenging because of the extreme neutron-to-proton ratio and the proximity of the continuum. In this study, we predict the J π = 2more » $$+\\atop{1}$$ state in 78Ni from a correlation with the J π = 2$$+\\atop{1}$$ state in 48Ca using chiral nucleon-nucleon and three-nucleon interactions. Our results confirm that 78Ni is doubly magic, and the predicted low-lying states of 79,80Ni open the way for shell-model studies of many more rare isotopes.« less
Λ N → NN EFT potentials and hypertriton non-mesonic weak decay
NASA Astrophysics Data System (ADS)
Pérez-Obiol, Axel; Entem, David R.; Nogga, Andreas
2018-05-01
The potential for the Λ N → NN weak transition, the main responsible for the non-mesonic weak decay of hypernuclei, has been developed within the framework of effective field theory (EFT) up to next-to-leading order (NLO). The leading order (LO) and NLO contributions have been calculated in both momentum and coordinate space, and have been organised into the different operators which mediate the N → NN transition. We compare the ranges of the one-meson and two-pion exchanges for each operator. The non-mesonic weak decay of the hypertriton has been computed within the plane-wave approximation using the LO weak potential and modern strong EFT NN potentials. Formally, two methods to calculate the final state interactions among the decay products are presented. We briefly comment on the calculation of the {}{{Λ }}{}3H{\\to }3 He+{π }- mesonic weak decay.
Army Communicator. Volume 34, Number 1, Winter 2009
2009-01-01
First, I will double- tap Yingling’s asser- tion that during the 1990s the United States repeatedly failed to estimate the likelihood of success in...country terrain, WIN-T Increment Two and Three lead test engineer Kenneth Hutchin- son has said. The 30 node EFT held at Fort Huachuca, Ariz...Transmission Systems DoD – Department of Defense EFT – Engineering Field Tests ESB – Expeditionary Signal Battalion FEMA – Federal Emergency Management
Extraction of In-Medium Nucleon-Nucleon Amplitude From Experiment
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Cucinotta, Francis A.; Wilson, John W.
1998-01-01
The in-medium nucleon-nucleon amplitudes are extracted from the available proton-nucleus total reaction cross sections data. The retrieval of the information from the experiment makes the estimate of reaction cross sections very reliable. Simple expressions are given for the in-medium nucleon-nucleon amplitudes for any system of colliding nuclei as a function of energy. Excellent agreement with experimental observations is demonstrated in the ion-nucleus interactions.
Similarity-transformed chiral NN + 3N interactions for the ab initio description of 12C and 16O.
Roth, Robert; Langhammer, Joachim; Calci, Angelo; Binder, Sven; Navrátil, Petr
2011-08-12
We present first ab initio no-core shell model (NCSM) calculations using similarity renormalization group (SRG) transformed chiral two-nucleon (NN) plus three-nucleon (3N) interactions for nuclei throughout the p-shell, particularly (12)C and (16)O. By introducing an adaptive importance truncation for the NCSM model space and an efficient JT-coupling scheme for the 3N matrix elements, we are able to surpass previous NCSM studies including 3N interactions. We present ground and excited states in (12)C and (16)O for model spaces up to N(max) = 12 including full 3N interactions. We analyze the contributions of induced and initial 3N interactions and probe induced 4N terms through the sensitivity of the energies on the SRG flow parameter. Unlike for light p-shell nuclei, SRG-induced 4N contributions originating from the long-range two-pion terms of the chiral 3N interaction are sizable in (12)C and (16)O.
Enhanced Flight Termination System (EFTS): Flight Demonstration and Results
NASA Technical Reports Server (NTRS)
Tow, David; Arce, Dennis
2008-01-01
The Enhanced Flight Termination System (EFTS) program was initiated and propelled due to the inadvertent terminations of Global Hawk and the Strategic Target System and the NASA Inspector General's assessment letter and recommendations regarding the exploration of low-cost, lightweight space COMSEC for FTS. Additionally, the standard analog and high alphabet systems most commonly used in FTS are secure, but not encrypted. A study group was initiated to select and document a robust, affordable, reliable technology that provides encrypted FTS capability. A flight demonstration was conducted to gain experience using EFTS in an operational environment, provide confidence in the use of the EFTS components, integrate EFTS into an existing range infrastructure to demonstrate the scalability of system components, to provide a command controller that generated the EFTS waveform using an existing range infrastructure, and to provide a report documenting the results of the demonstration. The primary goal of the demonstration was to obtain operational experience with EFTS. Areas of operational experience include: mission planning, pre-flight configuration and testing, mission monitoring and recording, vehicle termination, developing mission procedures. and post mission data reduction and other post mission activities. An Advanced Medium-Range Air-to-Air Missile (AMRAAM) was selected to support the EFTS demonstration due to interest in future use of EFTS by the AMRAAM program, familiarity of EFTS by range personnel, and the availability of existing operational environment to support EFTS testing with available program funding. For demonstration purposes, the AMRAAM was successfully terminated using an EFTS receiver and successfully demonstrating EFTS. The EFTS monitoring software with spectrum analyzer and digital graphical display of aircraft, missile, and target were also demonstrated.
Neutron yields from 155 MeV/nucleon carbon and helium stopping in aluminum
NASA Technical Reports Server (NTRS)
Heilbronn, L.; Cary, R. S.; Cronqvist, M.; Deak, F.; Frankel, K.; Galonsky, A.; Holabird, K.; Horvath, A.; Kiss, A.; Kruse, J.;
1999-01-01
Neutron fluences have been measured from 155 MeV/nucleon 4He and 12C ions stopping in an Al target at laboratory angles between 10 and 160 deg. The resultant spectra were integrated over angle and energy above 10 MeV to produce total neutron yields. Comparison of the two systems shows that approximately two times as many neutrons are produced from 155 MeV/nucleon 4He stopping in Al and 155 MeV/nucleon 12C stopping in Al. Using an energy-dependent geometric cross-section formula to calculate the expected number of primary nuclear interactions shows that the 12C + Al system has, within uncertainties, the same number of neutrons per interaction (0.99 +/- 0.03) as does the 4He + Al system (1.02 +/- 0.04), despite the fact that 12C has three times as many neutrons as does 4He. Energy and angular distributions for both systems are also reported. No major differences can be seen between the two systems in those distributions, except for the overall magnitude. Where possible, the 4He + Al spectra are compared with previously measured spectra from 160 and 177.5 MeV/nucleon 4He interactions in a variety of stopping targets. The reported spectra are consistent with previously measured spectra. The data were acquired to provide data applicable to problems dealing with the determination of the radiation risk to humans engaged in long-term missions in space; however, the data are also of interest for issues related to the determination of the radiation environment in high-altitude flight, with shielding at high-energy heavy-ion accelerators and with doses delivered outside tumor sites treated with high-energy hadronic beams.
Many body effects in nuclear matter QCD sum rules
NASA Astrophysics Data System (ADS)
Drukarev, E. G.; Ryskin, M. G.; Sadovnikova, V. A.
2017-12-01
We calculate the single-particle nucleon characteristics in symmetric nuclear matter with inclusion of the 3N and 4N interactions. We calculated the contribution of the 3N interactions earlier, now we add that of the 4N ones. The contribution of the 4N forces to nucleon self energies is expressed in terms of the nonlocal scalar condensate (d = 3) and of the configurations of the vector-scalar and the scalar-scalar quark condensates (d = 6) in which two diquark operators act on two different nucleons of the matter.These four-quark condensates are obtained in the model-independent way. The density dependence of the nucleon effective mass, of the vector self energy and of the single-particle potential energy are obtained. We traced the dependence of the nucleon characteristics on the actual value of the pion-nucleon sigma term. We obtained also the nucleon characteristics in terms of the quasifree nucleons, with the noninteracting nucleons surrounded by their pion clouds as the starting point. This approach leads to strict hierarchy of the many body forces.
Proportional Counter Calibration and Analysis for 12C + p Resonance Scattering
NASA Astrophysics Data System (ADS)
Nelson, Austin; Rogachev, Grigory; Uberseder, Ethan; Hooker, Josh; Koshchiy, Yevgen
2014-09-01
Light exotic nuclei provide a unique opportunity to test the predictions of modern ab initio theoretical calculations near the drip line. In ab initio approaches, nuclear structure is described starting from bare nucleon-nucleon and three-nucleon interactions. Calculations are very heavy and can only be performed for the lightest nuclei (A < 16). Experimental information on the structure of light exotic nuclei is crucial to determine the validity of these calculations and to fix the parameters for the three-nucleon forces. Resonance scattering with rare isotope beams is a very effective tool to study spectroscopy of nuclei near the drip line. A new setup was developed at the Cyclotron Institute for effective resonance scattering measurements. The setup includes ionization chamber, silicon array, and an array of proportional counters. The proportional counter array, consisting of 8 anode wires arranged in a parallel cellular grid, is used for particle identification and to track the positioning of light recoils. The main objective of this project was to test the performance and perform position calibration of this proportional counter array. The test was done using 12C beam. The excitation function for 12C + p elastic scattering was measured and calibration of the proportional counter was performed using known resonances in 13N. The method of calibration, including solid angle calculations, normalization corrections, and position calibration will be presented. Light exotic nuclei provide a unique opportunity to test the predictions of modern ab initio theoretical calculations near the drip line. In ab initio approaches, nuclear structure is described starting from bare nucleon-nucleon and three-nucleon interactions. Calculations are very heavy and can only be performed for the lightest nuclei (A < 16). Experimental information on the structure of light exotic nuclei is crucial to determine the validity of these calculations and to fix the parameters for the three-nucleon forces. Resonance scattering with rare isotope beams is a very effective tool to study spectroscopy of nuclei near the drip line. A new setup was developed at the Cyclotron Institute for effective resonance scattering measurements. The setup includes ionization chamber, silicon array, and an array of proportional counters. The proportional counter array, consisting of 8 anode wires arranged in a parallel cellular grid, is used for particle identification and to track the positioning of light recoils. The main objective of this project was to test the performance and perform position calibration of this proportional counter array. The test was done using 12C beam. The excitation function for 12C + p elastic scattering was measured and calibration of the proportional counter was performed using known resonances in 13N. The method of calibration, including solid angle calculations, normalization corrections, and position calibration will be presented. Funded by DOE and NSF-REU Program; Grant No. PHY-1263281.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quaglioni, S.
2016-09-22
A 2011 DOE-NP Early Career Award (ECA) under Field Work Proposal (FWP) SCW1158 supported the project “Solving the Long-Standing Problem of Low-Energy Nuclear Reactions at the Highest Microscopic Level” in the five-year period from June 15, 2011 to June 14, 2016. This project, led by PI S. Quaglioni, aimed at developing a comprehensive and computationally efficient framework to arrive at a unified description of structural properties and reactions of light nuclei in terms of constituent protons and neutrons interacting through nucleon-nucleon (NN) and three-nucleon (3N) forces. Specifically, the project had three main goals: 1) arriving at the accurate predictions formore » fusion reactions that power stars and Earth-based fusion facilities; 2) realizing a comprehensive description of clustering and continuum effects in exotic nuclei, including light Borromean systems; and 3) achieving fundamental understanding of the role of the 3N force in nuclear reactions and nuclei at the drip line.« less
How to use the Standard Model effective field theory
Henning, Brian; Lu, Xiaochuan; Murayama, Hitoshi
2016-01-06
Here, we present a practical three-step procedure of using the Standard Model effective field theory (SM EFT) to connect ultraviolet (UV) models of new physics with weak scale precision observables. With this procedure, one can interpret precision measurements as constraints on a given UV model. We give a detailed explanation for calculating the effective action up to one-loop order in a manifestly gauge covariant fashion. This covariant derivative expansion method dramatically simplifies the process of matching a UV model with the SM EFT, and also makes available a universal formalism that is easy to use for a variety of UVmore » models. A few general aspects of RG running effects and choosing operator bases are discussed. Finally, we provide mapping results between the bosonic sector of the SM EFT and a complete set of precision electroweak and Higgs observables to which present and near future experiments are sensitive. Many results and tools which should prove useful to those wishing to use the SM EFT are detailed in several appendices.« less
Pionic retardation effects in two-pion-exchange three-nucleon forces
NASA Astrophysics Data System (ADS)
Coon, S. A.; Friar, J. L.
1986-09-01
Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v/c)2 relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential.
The Antiproton-Nucleon Annihilation Process (Antiproton Collaboration Experiment)
DOE R&D Accomplishments Database
Barkas, W. H.; Birge, R. W.; Chupp, W. W.; Ekspong, A. G.; Goldhaber, G.; Goldhaber, S.; Heckman, H. H.; Perkins, D. H.; Sandweiss, J.; Segre, E.; Smith, F. M.; Stork, D. H.; Rossum, L. Van; Amaldi, E.; Baroni, G.; Castagnoli, C.; Franzinetti, C.; Manfredini, A.
1956-09-10
In the exposure to a 700-MeV/c negative particle beam, 35 antiproton stars have been found. Of these antiprotons, 21 annihilate in flight and three give large-angle scatters ({Theta} > 15 , T{sub P-} > 50 Mev), while 14 annihilate at rest. From the interactions in flight we obtain the total cross section for antiproton interaction.
Lattice quantum chromodynamical approach to nuclear physics
NASA Astrophysics Data System (ADS)
Aoki, Sinya; Doi, Takumi; Hatsuda, Tetsuo; Ikeda, Yoichi; Inoue, Takashi; Ishii, Noriyoshi; Murano, Keiko; Nemura, Hidekatsu; Sasaki, Kenji; HAL QCD Collaboration
2012-09-01
We review recent progress in the HAL QCD method, which was recently proposed to investigate hadron interactions in lattice quantum chromodynamics (QCD). The strategy to extract the energy-independent non-local potential in lattice QCD is explained in detail. The method is applied to study nucleon-nucleon, nucleon-hyperon, hyperon-hyperon, and meson-baryon interactions. Several extensions of the method are also discussed.
Relativistic Few-Body Hadronic Physics Calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Polyzou, Wayne
2016-06-20
The goal of this research proposal was to use ``few-body'' methods to understand the structure and reactions of systems of interacting hadrons (neutrons, protons, mesons, quarks) over a broad range of energy scales. Realistic mathematical models of few-hadron systems have the advantage that they are sufficiently simple that they can be solved with mathematically controlled errors. These systems are also simple enough that it is possible to perform complete accurate experimental measurements on these systems. Comparison between theory and experiment puts strong constraints on the structure of the models. Even though these systems are ``simple'', both the experiments and computationsmore » push the limits of technology. The important property of ``few-body'' systems is that the ``cluster property'' implies that the interactions that appear in few-body systems are identical to the interactions that appear in complicated many-body systems. Of particular interest are models that correctly describe physics at distance scales that are sensitive to the internal structure of the individual nucleons. The Heisenberg uncertainty principle implies that in order to be sensitive to physics on distance scales that are a fraction of the proton or neutron radius, a relativistic treatment of quantum mechanics is necessary. The research supported by this grant involved 30 years of effort devoted to studying all aspects of interacting two and three-body systems. Realistic interactions were used to compute bound states of two- and three-nucleon, and two- and three-quark systems. Scattering observables for these systems were computed for a broad range of energies - from zero energy scattering to few GeV scattering, where experimental evidence of sub-nucleon degrees of freedom is beginning to appear. Benchmark calculations were produced, which when compared with calculations of other groups provided an essential check on these complicated calculations. In addition to computing bound state properties and scattering cross section, we also computed electron scattering cross sections in few-nucleon and few-quark systems, which are sensitive to the electric currents in these systems. We produced the definitive review on article on relativistic quantum mechanics, which and been used by many groups. In addition we developed and tested many computational techniques are used by other groups. Many of these techniques have applications in other areas of physics. The research benefited by collaborations with physicists from many different institutions and countries. It also involved working with seventeen undergraduate and graduate students.« less
The Leuven Embedded Figures Test (L-EFT): measuring perception, intelligence or executive function?
Van der Hallen, Ruth; Wagemans, Johan; de-Wit, Lee; Chamberlain, Rebecca
2018-01-01
Performance on the Embedded Figures Test (EFT) has been interpreted as a reflection of local/global perceptual style, weak central coherence and/or field independence, as well as a measure of intelligence and executive function. The variable ways in which EFT findings have been interpreted demonstrate that the construct validity of this measure is unclear. In order to address this lack of clarity, we investigated to what extent performance on a new Embedded Figures Test (L-EFT) correlated with measures of intelligence, executive functions and estimates of local/global perceptual styles. In addition, we compared L-EFT performance to the original group EFT to directly contrast both tasks. Taken together, our results indicate that performance on the L-EFT does not correlate strongly with estimates of local/global perceptual style, intelligence or executive functions. Additionally, the results show that performance on the L-EFT is similarly associated with memory span and fluid intelligence as the group EFT. These results suggest that the L-EFT does not reflect a general perceptual or cognitive style/ability. These results further emphasize that empirical data on the construct validity of a task do not always align with the face validity of a task. PMID:29607257
Pionic retardation effects in two-pion-exchange three-nucleon forces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coon, S.A.; Friar, J.L.
1986-09-01
Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v-italic/c-italic)/sup 2/ relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and inmore » the specification of the choice of ambiguity parameters in the latter potential.« less
Forward Bay Cover Separation Modeling and Testing for the Orion Multi-Purpose Crew Vehicle
NASA Technical Reports Server (NTRS)
Ali, Yasmin; Radke, Tara; Chuhta, Jesse; Hughes, Michael
2014-01-01
Spacecraft multi-body separation events during atmospheric descent require complex testing and analysis to validate the flight separation dynamics model and to verify no recontact. NASA Orion Multi-Purpose Crew Vehicle (MPCV) teams examined key model parameters and risk areas to develop a robust but affordable test campaign in order to validate and verify the Forward Bay Cover (FBC) separation event for Exploration Flight Test-1 (EFT-1). The FBC jettison simulation model is highly complex, consisting of dozens of parameters varied simultaneously, with numerous multi-parameter interactions (coupling and feedback) among the various model elements, and encompassing distinct near-field, mid-field, and far-field regimes. The test campaign was composed of component-level testing (for example gas-piston thrusters and parachute mortars), ground FBC jettison tests, and FBC jettison air-drop tests that were accomplished by a highly multi-disciplinary team. Three ground jettison tests isolated the testing of mechanisms and structures to anchor the simulation models excluding aerodynamic effects. Subsequently, two air-drop tests added aerodynamic and parachute parameters, and served as integrated system demonstrations, which had been preliminarily explored during the Orion Pad Abort-1 (PA-1) flight test in May 2010. Both ground and drop tests provided extensive data to validate analytical models and to verify the FBC jettison event for EFT-1, but more testing is required to support human certification, for which NASA and Lockheed Martin are applying knowledge from Apollo and EFT-1 testing and modeling to develop a robust but affordable human spacecraft capability.
Three-Body Forces and the Limit of Oxygen Isotopes
NASA Astrophysics Data System (ADS)
Otsuka, Takaharu; Suzuki, Toshio; Holt, Jason D.; Schwenk, Achim; Akaishi, Yoshinori
2010-07-01
The limit of neutron-rich nuclei, the neutron drip line, evolves regularly from light to medium-mass nuclei except for a striking anomaly in the oxygen isotopes. This anomaly is not reproduced in shell-model calculations derived from microscopic two-nucleon forces. Here, we present the first microscopic explanation of the oxygen anomaly based on three-nucleon forces that have been established in few-body systems. This leads to repulsive contributions to the interactions among excess neutrons that change the location of the neutron drip line from O28 to the experimentally observed O24. Since the mechanism is robust and general, our findings impact the prediction of the most neutron-rich nuclei and the synthesis of heavy elements in neutron-rich environments.
Neutrino Nucleon Elastic Scattering in MiniBooNE
NASA Astrophysics Data System (ADS)
Cox, D. Christopher
2007-12-01
Neutrino nucleon elastic scattering νN→νN is a fundamental process of the weak interaction, and can be used to study the structure of the nucleon. This is the third largest scattering process in MiniBooNE comprising ˜15% of all neutrino interactions. Analysis of this sample has yielded a neutral current elastic differential cross section as a function of Q2 that agrees within errors to model predictions.
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – A barge arrives at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. The core booster and starboard booster will be offloaded and then transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – Two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The core booster and starboard booster will be offloaded and then transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – Two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The core booster and starboard booster were offloaded and are being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – Two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The core booster and starboard booster have been offloaded and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Focus on the future: Episodic future thinking reduces discount rate and snacking.
Dassen, Fania C M; Jansen, Anita; Nederkoorn, Chantal; Houben, Katrijn
2016-01-01
Obesity seems related to a preference for immediate gratification. By changing this focus on short term benefits to a more future-oriented outlook, delay discounting (impulsive decision making) can be changed by a manipulation of episodic future thinking (EFT). EFT comprises a vivid mental simulation of general future experiences. EFT may also affect consumption of unhealthy foods, which can be seen as a choice for immediate gratification. Recent research shows that future orientation should be tailored to the behavior at outcome. We therefore hypothesize that the effectiveness of EFT on food intake could be enhanced by making the content food-related. We conducted a 2 (future vs past thinking) by 2 (food vs non-food related thoughts) between-subject design experiment in female undergraduates (N = 94), to compare the efficacy of EFT versus the recalling of episodic past events in reducing discount rate and caloric intake. Content of imagery was either unrestricted or food-related. Participants engaged in EFT or control episodic imagery while snacks were offered to freely consume, and next the Monetary Choice Questionnaire was completed as a measure of delay discounting, while again being engaged in EFT or control imagery. Both types of EFT reduced delay discounting, however, only food-related EFT lead to more restricted caloric consumption. Thus, we found evidence that EFT reduced discount rate during decision making. However, in order to restrict caloric intake, EFT should entail food-related imagery. As discount rate and caloric intake were not related in the current sample, the underlying mechanism remains to be discovered. Results however suggest that EFT is a promising technique to resist immediate gratification. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Witała, H.; Golak, J.; Skibiński, R.; Topolnicki, K.; Kamada, H.
We discuss the importance of the three-nucleon isospin T = 3/2 component in elastic neutron-deuteron scattering and in the deuteron breakup reaction. The contribution of this amplitude originates from charge-independence breaking of the nucleon-nucleon potential. We study the magnitude of that contribution to the elastic scattering and breakup observables, taking the Av18 nucleon-nucleon potential alone or combined with the Urbana IX three-nucleon force as well as the locally regularized chiral N4LO nucleon-nucleon potential alone or supplemented by the chiral N2LO three-nucleon force. We find that the isospin T = 3/2 component is important for the breakup reaction and the proper treatment of charge-independence breaking in this case requires the inclusion of the 1S 0 state with isospin T = 3/2. For neutron-deuteron elastic scattering the T = 3/2 contributions are insignificant and charge-independence breaking can be accounted for by neglecting T = 3/2 component and using the effective t-matrix generated with the so-called “2/3 ‑ 1/3″ rule.
Nuclear half-lives for {alpha}-radioactivity of elements with 100 {<=} Z {<=} 130
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chowdhury, P. Roy; Samanta, C.; Physics Department, Gottwald Science Center, University of Richmond, Richmond, VA 23173
2008-11-15
Theoretical estimates for the half-lives of about 1700 isotopes of heavy elements with 100 {<=} Z {<=} 130 are tabulated using theoretical Q-values. The quantum mechanical tunneling probabilities are calculated within a WKB framework using microscopic nuclear potentials. The microscopic nucleus-nucleus potentials are obtained by folding the densities of interacting nuclei with a density-dependent M3Y effective nucleon-nucleon interaction. The {alpha}-decay half-lives calculated in this formalism using the experimental Q-values were found to be in good agreement over a wide range of experimental data spanning about 20 orders of magnitude. The theoretical Q-values used for the present calculations are extracted frommore » three different mass estimates viz. Myers-Swiatecki, Muntian-Hofmann-Patyk-Sobiczewski, and Koura-Tachibana-Uno-Yamada.« less
NASA Astrophysics Data System (ADS)
Armendariz, Raul L.
Measuring energy produced in relativistic heavy-ion collisions is a way to investigate if a model of quark participants, or nucleon participants better describes the internal dynamics of the collision. The energy produced is proportional to the energy density in the interaction region; changes in fluctuations of energy production could be a signature for a phase transition between ordinary hadronic matter to a liberated quark-gluon plasma phase, QGP, thought to have existed one millionth of a second after the Big Bang creation of the Universe and before protons and neutrons had formed. Three experimental nuclear physics data-analyses were conducted using the sum energy of all particles produced in the direction transverse to the beam, ET, when nuclei collide in a 2.4 mile long circular atom smasher. The nuclei are accelerated in opposite directions at 99.995% the speed of light, and center-of-mass energies available for new particle production of sNN = 62.4 GeV, and 200 GeV per colliding nucleon pair were studied. The ET was recorded by the lead-scintillator electromagnetic calorimeter detectors of the Pioneering High Energy Interactions Experiment (PHENIX), at the Relativistic heavy Ion Collider (RHIC), of Brookhaven National Laboratory (BNL). The collision systems studied were 200 GeV protons with protons ( p + p), deuterons with Au ions (d+Au), and 62.4 GeV and 200 GeV gold ions with gold ions (Au+Au). The first analysis, mean ET in collision centrality, explores whether a model of nucleon participants, or quark participants, better describes energy production with collision impact. The second analysis, ET fluctuations in collision centrality, looks for non-random fluctuations in ET distributions when the density of colliding partons becomes high. The third analysis, ET fluctuations in geometric acceptance, examines fluctuations as a function of detector fiducial volume in a search for correlated energy distribution in space (correlations ), known to occur in phenomena such as elliptic flow and particle jets. The Au+Au results are as follows. In both 62.4 GeV and 200 GeV interactions mean ET production per participant nucleon rises steadily, and per participant quark remains constant to within the identified errors. In both 62.4 GeV and 200 GeV collisions energy densities estimated for QGP formation were measured: at 200 GeV these levels of 1 GeV/fm 3, to 3 GeV/fm3 were measured in interactions of 30 and 150 participant nucleons respectively (corresponding to the 60-65%, and 25-30% centrality classes of data). In neither 62.4 GeV nor 200 GeV interactions are changes in fluctuations over collision impact observed above the 40% systematic errors introduced by the centrality definitions. Fluctuations in acceptance for the 200 GeV 0-5% most central class of collisions, corresponding to 350 participant nucleons, exhibit a 115% rise in a 6-fold increase of the transverse angle; from this a correlation-length of 3.1° is calculated; removal of known contamination effects to the fluctuations from event reaction-plane rotation and elliptic-flow are under investigation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walker-Loud, Andre
The research supported by this grant is aimed at probing the limits of the Standard Model through precision low-energy nuclear physics. The work of the PI (AWL) and additional personnel is to provide theory input needed for a number of potentially high-impact experiments, notably, hadronic parity violation, Dark Matter direct detection and searches for permanent electric dipole moments (EDMs) in nucleons and nuclei. In all these examples, a quantitative understanding of low-energy nuclear physics from the fundamental theory of strong interactions, Quantum Chromo-Dynamics (QCD), is necessary to interpret the experimental results. The main theoretical tools used and developed in thismore » work are the numerical solution to QCD known as lattice QCD (LQCD) and Effective Field Theory (EFT). This grant is supporting a new research program for the PI, and as such, needed to be developed from the ground up. Therefore, the first fiscal year of this grant, 08/01/2014-07/31/2015, has been spent predominantly establishing this new research effort. Very good progress has been made, although, at this time, there are not many publications to show for the effort. After one year, the PI accepted a job at Lawrence Berkeley National Laboratory, so this final report covers just a single year of five years of the grant.« less
Spin-Flavor van der Waals Forces and NN interaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alvaro Calle Cordon, Enrique Ruiz Arriola
A major goal in Nuclear Physics is the derivation of the Nucleon-Nucleon (NN) interaction from Quantum Chromodynamics (QCD). In QCD the fundamental degrees of freedom are colored quarks and gluons which are confined to form colorless strongly interacting hadrons. Because of this the resulting nuclear forces at sufficiently large distances correspond to spin-flavor excitations, very much like the dipole excitations generating the van der Waals (vdW) forces acting between atoms. We study the Nucleon-Nucleon interaction in the Born-Oppenheimer approximation at second order in perturbation theory including the Delta resonance as an intermediate state. The potential resembles strongly chiral potentials computedmore » either via soliton models or chiral perturbation theory and has a van der Waals like singularity at short distances which is handled by means of renormalization techniques. Results for the deuteron are discussed.« less
Continuum and three-nucleon force effects on Be 9 energy levels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Langhammer, Joachim; Navrátil, Petr; Quaglioni, Sofia
2015-02-05
In this paper, we extend the recently proposed ab initio no-core shell model with continuum to include three-nucleon (3N) interactions beyond the few-body domain. The extended approach allows for the assessment of effects of continuum degrees of freedom as well as of the 3N force in ab initio calculations of structure and reaction observables of p- and lower-sd-shell nuclei. As a first application we concentrate on energy levels of the 9Be system for which all excited states lie above the n- 8Be threshold. For all energy levels, the inclusion of the continuum significantly improves the agreement with experiment, which wasmore » an issue in standard no-core shell model calculations. Furthermore, we find the proper treatment of the continuum indispensable for reliable statements about the quality of the adopted 3N interaction from chiral effective field theory. Finally, in particular, we find the 1/2 + resonance energy, which is of astrophysical interest, in good agreement with experiment.« less
Graeff, Daniela Bertol; Foppa, Murilo; Pires, Julio Cesar Gall; Vigo, Alvaro; Schmidt, Maria Ines; Lotufo, Paulo Andrade; Mill, Jose Geraldo; Duncan, Bruce Bartholow
2016-04-01
Epicardial fat thickness (EFT) has emerged as a marker of cardiometabolic risk, but its clinical use warrants proper knowledge of its distribution and associations in populations. We aimed to describe the distribution of EFT, its demographic correlates and independent associations with diabetes, hypertension and metabolic syndrome (MS) in free-living Brazilian adults. From the baseline echocardiography of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)-a cohort study of civil servants aged 35-74 years-EFT was measured from a randomly selected sample of 998 participants as the mean of two paraesternal windows obtained at end systole (EFTsyst) and end diastole (EFTdiast). From the 421 individuals free of diabetes, hypertension and MS, we defined EFT reference values and the EFTsyst 75th percentile cut-off. Median EFTsyst was 1.5 (IQR 0-2.6) mm; a large proportion (84 %) had EFTdiast = 0. EFT was higher in women and lower in blacks, and increased with age and BMI. Although EFT was higher in those with diabetes, hypertension, and MS, EFT associations were reduced when adjusted for age, sex and ethnicity, and were non-significant after adjusting for obesity measures. In conclusion, the amount of EFT in this large multiethnic population is smaller than reported in other populations. EFT reference values varied across demographic and clinical variables, EFT associations with cardiometabolic variables being largely explained by age, sex, ethnicity and central obesity. Although EFT can help identify individuals at increased cardiometabolic risk, it will likely have a limited additional role compared to current risk stratification strategies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Acciarri, R.; Adams, C.; Asaadi, J.
2014-07-01
Short range nucleon-nucleon correlations in nuclei (NN SRC) carry important information on nuclear structure and dynamics. NN SRC have been extensively probed through two-nucleon knock- out reactions in both pion and electron scattering experiments. We report here on the detection of two-nucleon knock-out events from neutrino interactions and discuss their topological features as possibly involving NN SRC content in the target argon nuclei. The ArgoNeuT detector in the Main Injector neutrino beam at Fermilab has recorded a sample of 30 fully reconstructed charged current events where the leading muon is accompanied by a pair of protons at the interaction vertex,more » 19 of which have both protons above the Fermi momentum of the Ar nucleus. Out of these 19 events, four are found with the two protons in a strictly back-to-back high momenta configuration directly observed in the final state and can be associated to nucleon Resonance pionless mechanisms involving a pre-existing short range correlated np pair in the nucleus. Another fraction (four events) of the remaining 15 events have a reconstructed back-to-back configuration of a np pair in the initial state, a signature compatible with one-body Quasi Elastic interaction on a neutron in a SRC pair. The detection of these two subsamples of the collected (mu- + 2p) events suggests that mechanisms directly involving nucleon-nucleon SRC pairs in the nucleus are active and can be efficiently explored in neutrino-argon interactions with the LAr TPC technology.« less
NASA Astrophysics Data System (ADS)
Wang, S. M.; Michel, N.; Nazarewicz, W.; Xu, F. R.
2017-10-01
Background: Weakly bound and unbound nuclear states appearing around particle thresholds are prototypical open quantum systems. Theories of such states must take into account configuration mixing effects in the presence of strong coupling to the particle continuum space. Purpose: To describe structure and decays of three-body systems, we developed a Gamow coupled-channel (GCC) approach in Jacobi coordinates by employing the complex-momentum formalism. We benchmarked the complex-energy Gamow shell model (GSM) against the new framework. Methods: The GCC formalism is expressed in Jacobi coordinates, so that the center-of-mass motion is automatically eliminated. To solve the coupled-channel equations, we use hyperspherical harmonics to describe the angular wave functions while the radial wave functions are expanded in the Berggren ensemble, which includes bound, scattering, and Gamow states. Results: We show that the GCC method is both accurate and robust. Its results for energies, decay widths, and nucleon-nucleon angular correlations are in good agreement with the GSM results. Conclusions: We have demonstrated that a three-body GSM formalism explicitly constructed in the cluster-orbital shell model coordinates provides results similar to those with a GCC framework expressed in Jacobi coordinates, provided that a large configuration space is employed. Our calculations for A =6 systems and 26O show that nucleon-nucleon angular correlations are sensitive to the valence-neutron interaction. The new GCC technique has many attractive features when applied to bound and unbound states of three-body systems: it is precise, is efficient, and can be extended by introducing a microscopic model of the core.
NASA Astrophysics Data System (ADS)
Rahmat, M.; Modarres, M.
2018-03-01
The averaged effective two-body interaction (AEI), which can be generated through the lowest order constrained variational (LOCV) method for symmetric nuclear matter (SNM) with the input [Reid68, Ann. Phys. 50, 411 (1968), 10.1016/0003-4916(68)90126-7] nucleon-nucleon potential, is used as the effective nucleon-nucleon potential in the folding model to describe the heavy-ion (HI) elastic scattering cross sections. The elastic scattering cross sections of 12C-12C and 16O-16O systems are calculated in the above framework. The results are compared with the corresponding calculations coming from the fitting procedures with the input finite range D D M 3 Y 1 -Reid potential and the available experimental data at different incident energies. It is shown that a reasonable description of the elastic 12C-12C and 16O-16O scattering data at the low and medium energies can be obtained by using the above LOCV AEI, without any need to define a parametrized density-dependent function in the effective nucleon-nucleon potential, which is formally considered in the typical D D M 3 Y 1 -Reid interactions.
N3LO NN interaction adjusted to light nuclei in ab exitu approach
Shirokov, A. M.; Shin, I. J.; Kim, Y.; ...
2016-08-09
Here, we use phase-equivalent transformations to adjust off-shell properties of similarity renormalization group evolved chiral effective field theory NN interaction (Idaho N3LO) to fit selected binding energies and spectra of light nuclei in an ab exitu approach. Then, we test the transformed interaction on a set of additional observables in light nuclei to verify that it provides reasonable descriptions of these observables with an apparent reduced need for three- and many-nucleon interactions.
Orion Exploration Flight Test-l (EFT -1) Absolute Navigation Design
NASA Technical Reports Server (NTRS)
Sud, Jastesh; Gay, Robert; Holt, Greg; Zanetti, Renato
2014-01-01
Scheduled to launch in September 2014 atop a Delta IV Heavy from the Kennedy Space Center, the Orion Multi-Purpose-Crew-Vehicle (MPCV's) maiden flight dubbed "Exploration Flight Test -1" (EFT-1) intends to stress the system by placing the uncrewed vehicle on a high-energy parabolic trajectory replicating conditions similar to those that would be experienced when returning from an asteroid or a lunar mission. Unique challenges associated with designing the navigation system for EFT-1 are presented in the narrative with an emphasis on how redundancy and robustness influenced the architecture. Two Inertial Measurement Units (IMUs), one GPS receiver and three barometric altimeters (BALTs) comprise the navigation sensor suite. The sensor data is multiplexed using conventional integration techniques and the state estimate is refined by the GPS pseudorange and deltarange measurements in an Extended Kalman Filter (EKF) that employs the UDUT decomposition approach. The design is substantiated by simulation results to show the expected performance.
2014-06-30
CAPE CANAVERAL, Fla. – Inside the Delta Operations Center near Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the second stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is lowered by crane into a cradle for the move to a test cell. At the Horizontal Integration Facility, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Frankie Martin
2014-06-30
CAPE CANAVERAL, Fla. – Inside the Delta Operations Center near Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the second stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is lowered by crane into a cradle for the move to a test cell. At the Horizontal Integration Facility, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Frankie Martin
2014-06-30
CAPE CANAVERAL, Fla. – Inside the Delta Operations Center near Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the second stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is lowered by crane into a cradle for the move to a test cell. At the Horizontal Integration Facility, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Frankie Martin
2014-06-30
CAPE CANAVERAL, Fla. – Inside the Delta Operations Center near Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the second stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is lifted high by crane for the move to a test cell. At the Horizontal Integration Facility, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Frankie Martin
2014-06-30
CAPE CANAVERAL, Fla. – Inside the Delta Operations Center near Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the second stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is lifted high by crane into a test cell. At the Horizontal Integration Facility, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Frankie Martin
2014-06-30
CAPE CANAVERAL, Fla. – Inside the Delta Operations Center near Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the second stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is secured in its cradle for the move to a test cell. At the Horizontal Integration Facility, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Frankie Martin
Correlation between epicardial fat thickness and biochemical markers of metabolic risk.
Rubio-Guerra, Alberto Francisco; Benítez-Maldonado, Daniel Rabindranath; Lozano-Nuevo, José Juan; Arana-Pazos, Karla Corina; Huerta-Ramirez, Saul; Narváez-Rivera, Jorge Luis
2018-02-28
Epicardial fat has been associated with increased cardiovascular risk and the development of atherosclerosis. Transthoracic echocardiography provides a reliable measurement of epicardial fat thickness (EFT). The aim of this study is to evaluate the relationship between EFT and biochemical parameters of metabolic risk. We assessed 211 patients who underwent echocardiography; EFT was measured by two cardiologists. In addition, patients' glycaemia, lipid profile and serum uric acid were measured. Statistical analysis was performed with the Pearson coefficient test and Odds ratio. A positive correlation between EFT with glycaemia (r=.064), total serum cholesterol (r=.0056), high density lipoproteins (r=-.038), or with triglycerides (r=.118) was not observed. However, we did find a significant positive correlation between EFT and serum uric acid (r=.415, P<.00001). The odds ratio for EFT>3mm in patients with hyperuricemia was 6.26 (IC 95 2.79-14, P<.0001). Hyperuricemia is strongly associated with EFT in Mexican patients; EFT is a useful tool for global cardiovascular risk calculation. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.
Does Goal Relevant Episodic Future Thinking Amplify the Effect on Delay Discounting?
O’Donnell, Sara; Daniel, Tinuke Oluyomi; Epstein, Leonard H.
2017-01-01
Delay discounting (DD) is the preference for smaller immediate rewards over larger delayed rewards. Research shows episodic future thinking (EFT), or mentally simulating future experiences, reframes the choice between small immediate and larger delayed rewards, and can reduce DD. Only general EFT has been studied, whereby people reframe decisions in terms of non-goal related future events. Since future thinking is often goal-oriented and leads to greater activation of brain regions involved in prospection, goal-oriented EFT may be associated with greater reductions in DD than general goal-unrelated EFT. The present study (n = 104, Mage = 22.25, SD = 3.42; 50% Female) used a between-subjects 2×2 factorial design with type of episodic thinking (Goal, General) and temporal perspective (Episodic future versus recent thinking; EFT vs ERT) as between factors. Results showed a significant reduction in DD for EFT groups (p < 0.001, Cohen’s d effect size = 0.89), and goal-EFT was more effective than general-EFT on reducing DD (p = 0.03, d = 0.64). PMID:28282631
Does goal relevant episodic future thinking amplify the effect on delay discounting?
O'Donnell, Sara; Oluyomi Daniel, Tinuke; Epstein, Leonard H
2017-05-01
Delay discounting (DD) is the preference for smaller immediate rewards over larger delayed rewards. Research shows episodic future thinking (EFT), or mentally simulating future experiences, reframes the choice between small immediate and larger delayed rewards, and can reduce DD. Only general EFT has been studied, whereby people reframe decisions in terms of non-goal related future events. Since future thinking is often goal-oriented and leads to greater activation of brain regions involved in prospection, goal-oriented EFT may be associated with greater reductions in DD than general goal-unrelated EFT. The present study (n=104, M age =22.25, SD=3.42; 50% Female) used a between-subjects 2×2 factorial design with type of episodic thinking (Goal, General) and temporal perspective (Episodic future versus recent thinking; EFT vs ERT) as between factors. Results showed a significant reduction in DD for EFT groups (p<0.001, Cohen's d effect size=0.89), and goal-EFT was more effective than general-EFT on reducing DD (p=0.03, d=0.64). Copyright © 2017 Elsevier Inc. All rights reserved.
Episodic Future Thinking: Expansion of the Temporal Window in Individuals with Alcohol Dependence.
Snider, Sarah E; LaConte, Stephen M; Bickel, Warren K
2016-07-01
Episodic future thinking (EFT) requires an individual to vividly pre-experience a realistic future event. Inspired by previous reports of reducing delay discounting following EFT in other populations, we examined the effects of engaging alcohol-dependent individuals in EFT or episodic recent thinking (ERT; control) to examine its effects on delay discounting and alcohol purchasing. Participants (n = 50) with alcohol dependence were allocated into EFT or ERT groups and asked to generate positive future or recent past events for each of 5 time points. Participants then completed a delay-discounting task, during which event cues were displayed, and a hypothetical alcohol purchase task. EFT significantly increased valuation of future monetary rewards, while decreasing initial consumption (Q0 ) of alcoholic drinks indicative of lower demand intensity. Two additional findings suggest potential moderators of this effect. EFT more readily influenced individuals with lower Alcohol Use Disorders Identification Test scores, and self-reported cue valence differed between groups. Together, these results suggest a widening of alcohol-dependent individuals' temporal window following engagement of EFT. While our data suggest that EFT may be moderated by certain susceptibility criteria, exercises such as EFT could be easily adaptable as a potential therapeutic tool for use in rehabilitation programs. Copyright © 2016 by the Research Society on Alcoholism.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dawson, S.; Lewis, I. M.
One of the simplest extensions of the Standard Model (SM) is the addition of a scalar gauge singlet, S . If S is not forbidden by a symmetry from mixing with the Standard Model Higgs boson, the mixing will generate non-SM rates for Higgs production and decays. Generally, there could also be unknown high energy physics that generates additional effective low energy interactions. We show that interference effects between the scalar resonance of the singlet model and the effective field theory (EFT) operators can have significant effects in the Higgs sector. Here, we examine a non- Z 2 symmetricmore » scalar singlet model and demonstrate that a fit to the 125 GeV Higgs boson couplings and to limits on high mass resonances, S , exhibit an interesting structure and possible large cancellations of effects between the resonance contribution and the new EFT interactions, that invalidate conclusions based on the renormalizable singlet model alone.« less
Singlet model interference effects with high scale UV physics
Dawson, S.; Lewis, I. M.
2017-01-06
One of the simplest extensions of the Standard Model (SM) is the addition of a scalar gauge singlet, S . If S is not forbidden by a symmetry from mixing with the Standard Model Higgs boson, the mixing will generate non-SM rates for Higgs production and decays. Generally, there could also be unknown high energy physics that generates additional effective low energy interactions. We show that interference effects between the scalar resonance of the singlet model and the effective field theory (EFT) operators can have significant effects in the Higgs sector. Here, we examine a non- Z 2 symmetricmore » scalar singlet model and demonstrate that a fit to the 125 GeV Higgs boson couplings and to limits on high mass resonances, S , exhibit an interesting structure and possible large cancellations of effects between the resonance contribution and the new EFT interactions, that invalidate conclusions based on the renormalizable singlet model alone.« less
Final-state interactions in semi-inclusive deep inelastic scattering off the Deuteron
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wim Cosyn, Misak Sargsian
2011-07-01
Semi-inclusive deep inelastic scattering off the Deuteron with production of a slow nucleon in recoil kinematics is studied in the virtual nucleon approximation, in which the final state interaction (FSI) is calculated within general eikonal approximation. The cross section is derived in a factorized approach, with a factor describing the virtual photon interaction with the off-shell nucleon and a distorted spectral function accounting for the final-state interactions. One of the main goals of the study is to understand how much the general features of the diffractive high energy soft rescattering accounts for the observed features of FSI in deep inelasticmore » scattering (DIS). Comparison with the Jefferson Lab data shows good agreement in the covered range of kinematics. Most importantly, our calculation correctly reproduces the rise of the FSI in the forward direction of the slow nucleon production angle. By fitting our calculation to the data we extracted the W and Q{sup 2} dependences of the total cross section and slope factor of the interaction of DIS products, X, off the spectator nucleon. This analysis shows the XN scattering cross section rising with W and decreasing with an increase of Q{sup 2}. Finally, our analysis points at a largely suppressed off-shell part of the rescattering amplitude.« less
Nucleon-nucleon scattering from fully dynamical lattice QCD.
Beane, S R; Bedaque, P F; Orginos, K; Savage, M J
2006-07-07
We present results of the first fully dynamical lattice QCD determination of nucleon-nucleon scattering lengths in the 1S0 channel and 3S1 - 3D1 coupled channels. The calculations are performed with domain-wall valence quarks on the MILC staggered configurations with a lattice spacing of b = 0.125 fm in the isospin-symmetric limit, and in the absence of electromagnetic interactions.
NASA Astrophysics Data System (ADS)
Adel, A.; Alharbi, T.
2018-07-01
A systematic study on α-decay fine structure is presented for odd-mass nuclei in the range 83 ≤ Z ≤ 92. The α-decay partial half-lives and branching ratios to the ground and excited states of daughter nuclei are calculated in the framework of the Wentzel-Kramers-Brillouin (WKB) approximation with the implementation of the Bohr-Sommerfeld quantization condition. The microscopic α-daughter potential is obtained using the double-folding model with a realistic M3Y-Paris nucleon-nucleon (NN) interaction. The exchange potential, which accounts for the knock-on exchange of nucleons between the interacting nuclei, is calculated using the finite-range exchange NN interaction which is essentially a much better approximation as compared to the zero-range pseudo-potential adopted in the usual double-folding calculations. Our calculations of α-decay fine structure have been improved by considering the preformation factor extracted from the recently proposed cluster formation model on basis of the binding energy difference. The computed partial half-lives and branching ratios are compared with the recent experimental data and they are in good agreement.
Nucleon shadowing effects in Cu + Cu and Au + Au collisions at RHIC within the HIJING code
NASA Astrophysics Data System (ADS)
Abdel-Waged, Khaled; Felemban, Nuha
2018-02-01
The centrality dependence of pseudorapidity density of charged particles ({{{d}}{N}}{{ch}}/{{d}}η ) in Cu + Cu (Au + Au) collisions at Relativistic Heavy Ion Collider energy of \\sqrt{{s}{{NN}}}=22.4, 62.4 and 200 (19.6, 62.4 and 200) GeV, is investigated within an improved HIJING code. The standard HIJING model is enhanced by a prescription for collective nucleon-nucleon (NN) interactions and more modern parton distribution functions. The collective NN-interactions are used to induce both cascade and nucleon shadowing effects. We find collective cascade broadens the pseudorapidity distributions in the tails (at | η | > {y}{beam}) above 25%-30% collision centrality to be consistent with the {{{d}}{N}}{{ch}}/{{d}}η data at \\sqrt{{s}{{NN}}} =19.6,22.4,62.4 {GeV}. The overall contribution of nucleon shadowing is shown to depress the whole shape of {{{d}}{N}}{{ch}}/{{d}}η in the primary interaction region (at | η | < {y}{beam}) for semiperipheral (20%-25%) and peripheral (≥slant 35 % {--}40 % ) Cu + Cu (Au + Au) interactions at \\sqrt{{s}{{NN}}}=200 {GeV}, in accordance with the PHOBOS data.
Hadron-rich cosmic-ray families detected by emulsion chamber.
NASA Astrophysics Data System (ADS)
Navia, C. E.; Augusto, C. R. K.; Pinto, F. A.; Shibuya, H.
1995-11-01
Observed hadrons in excess, larger-than-expected charged mesons (pions) in cosmic-ray families detected in emulsion chamber experiment at mountain altitude and produced in a cosmic-ray hadronic interaction not far from the PeV energy region are studied. The hypothesis that these extra hadrons could be a bundle of surviving nuclear fragments (nucleons) is verified through a simulation method using a hybrid code composed of a superposition model to describe the number of interacting nucleon-nucleon pairs in a nucleus-nucleus collision. Together with the UA5 algorithm to describe a nucleon-nucleon collision, atmospheric propagation structure is also considered. A comparison between simulation output with experimental data shows that the surviving-nuclear-fragments hypothesis is not enough to explain the non-pionic hadron excess, even if a heavy dominance composition in the primary flux is considered.
On dark matter interactions with the Standard Model through an anomalous Z'
NASA Astrophysics Data System (ADS)
Ismail, Ahmed; Katz, Andrey; Racco, Davide
2017-10-01
We study electroweak scale Dark Matter (DM) whose interactions with baryonic matter are mediated by a heavy anomalous Z'. We emphasize that when the DM is a Majorana particle, its low-velocity annihilations are dominated by loop suppressed annihilations into the gauge bosons, rather than by p-wave or chirally suppressed annihilations into the SM fermions. Because the Z ' is anomalous, these kinds of DM models can be realized only as effective field theories (EFTs) with a well-defined cutoff, where heavy spectator fermions restore gauge invariance at high energies. We formulate these EFTs, estimate their cutoff and properly take into account the effect of the Chern-Simons terms one obtains after the spectator fermions are integrated out. We find that, while for light DM collider and direct detection experiments usually provide the strongest bounds, the bounds at higher masses are heavily dominated by indirect detection experiments, due to strong annihilation into W + W -, ZZ, Zγ and possibly into gg and γγ. We emphasize that these annihilation channels are generically significant because of the structure of the EFT, and therefore these models are prone to strong indirect detection constraints. Even though we focus on selected Z' models for illustrative purposes, our setup is completely generic and can be used for analyzing the predictions of any anomalous Z'-mediated DM model with arbitrary charges.
Yan, H; Snow, W M
2013-02-22
Various theories beyond the standard model predict new particles with masses in the sub-eV range with very weak couplings to ordinary matter. A parity-odd interaction between polarized nucleons and unpolarized matter proportional to g(V)g(A)s · p is one such possibility, where s[over →] and p[over →] are the spin and the momentum of the polarized nucleon, and g(V) and g(A) are the vector and axial vector couplings of an interaction induced by the exchange of a new light vector boson. We report a new experimental upper bound on such possible long-range parity-odd interactions of the neutron with nucleons and electrons from a recent search for parity violation in neutron spin rotation in liquid ^{4}He. Our constraint on the product of vector and axial vector couplings of a possible new light vector boson is g(V) g(A)(n) ≤ 10(-32) for an interaction range of 1 m. This upper bound is more than 7 orders of magnitude more stringent than the existing laboratory constraints for interaction ranges below 1 m, corresponding to a broad range of vector boson masses above 10(-6) eV. More sensitive searches for a g(V) g(A)(n) coupling could be performed using neutron spin rotation measurements in heavy nuclei or through analysis of experiments conducted to search for nucleon-nucleon weak interactions and nuclear anapole moments.
Forward Bay Cover Separation Modeling and Testing for the Orion Multi-Purpose Crew Vehicle
NASA Technical Reports Server (NTRS)
Ali, Yasmin; Chuhta, Jesse D.; Hughes, Michael P.; Radke, Tara S.
2015-01-01
Spacecraft multi-body separation events during atmospheric descent require complex testing and analysis to validate the flight separation dynamics models used to verify no re-contact. The NASA Orion Multi-Purpose Crew Vehicle (MPCV) architecture includes a highly-integrated Forward Bay Cover (FBC) jettison assembly design that combines parachutes and piston thrusters to separate the FBC from the Crew Module (CM) and avoid re-contact. A multi-disciplinary team across numerous organizations examined key model parameters and risk areas to develop a robust but affordable test campaign in order to validate and verify the FBC separation event for Exploration Flight Test-1 (EFT-1). The FBC jettison simulation model is highly complex, consisting of dozens of parameters varied simultaneously, with numerous multi-parameter interactions (coupling and feedback) among the various model elements, and encompassing distinct near-field, mid-field, and far-field regimes. The test campaign was composed of component-level testing (for example gas-piston thrusters and parachute mortars), ground FBC jettison tests, and FBC jettison air-drop tests that were accomplished by a highly multi-disciplinary team. Three ground jettison tests isolated the testing of mechanisms and structures to anchor the simulation models excluding aerodynamic effects. Subsequently, two air-drop tests added aerodynamic and parachute elements, and served as integrated system demonstrations, which had been preliminarily explored during the Orion Pad Abort-1 (PA-1) flight test in May 2010. Both ground and drop tests provided extensive data to validate analytical models and to verify the FBC jettison event for EFT-1. Additional testing will be required to support human certification of this separation event, for which NASA and Lockheed Martin are applying knowledge from Apollo and EFT-1 testing and modeling to develop a robust human-rated FBC separation event.
Effective field theory of statistical anisotropies for primordial bispectrum and gravitational waves
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rostami, Tahereh; Karami, Asieh; Firouzjahi, Hassan, E-mail: t.rostami@ipm.ir, E-mail: karami@ipm.ir, E-mail: firouz@ipm.ir
2017-06-01
We present the effective field theory studies of primordial statistical anisotropies in models of anisotropic inflation. The general action in unitary gauge is presented to calculate the leading interactions between the gauge field fluctuations, the curvature perturbations and the tensor perturbations. The anisotropies in scalar power spectrum and bispectrum are calculated and the dependence of these anisotropies to EFT couplings are presented. In addition, we calculate the statistical anisotropy in tensor power spectrum and the scalar-tensor cross correlation. Our EFT approach incorporates anisotropies generated in models with non-trivial speed for the gauge field fluctuations and sound speed for scalar perturbationsmore » such as in DBI inflation.« less
Self-consistent Models of Strong Interaction with Chiral Symmetry
DOE R&D Accomplishments Database
Nambu, Y.; Pascual, P.
1963-04-01
Some simple models of (renormalizable) meson-nucleon interaction are examined in which the nucleon mass is entirely due to interaction and the chiral ( gamma {sub 5}) symmetry is "broken'' to become a hidden symmetry. It is found that such a scheme is possible provided that a vector meson is introduced as an elementary field. (auth)
Spin symmetry in the Dirac sea derived from the bare nucleon-nucleon interaction
NASA Astrophysics Data System (ADS)
Shen, Shihang; Liang, Haozhao; Meng, Jie; Ring, Peter; Zhang, Shuangquan
2018-06-01
The spin symmetry in the Dirac sea has been investigated with relativistic Brueckner-Hartree-Fock theory using the bare nucleon-nucleon interaction. Taking the nucleus 16O as an example and comparing the theoretical results with the data, the definition of the single-particle potential in the Dirac sea is studied in detail. It is found that if the single-particle states in the Dirac sea are treated as occupied states, the ground state properties are in better agreement with experimental data. Moreover, in this case, the spin symmetry in the Dirac sea is better conserved and it is more consistent with the findings using phenomenological relativistic density functionals.
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – Two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The core booster, shown in this photo, and starboard booster were offloaded and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – Two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The core booster and starboard booster are being offloaded and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – Two of the three United Launch Alliance Delta IV heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The core booster, shown in this photo, and starboard booster were offloaded and transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Church, Dawson; Sparks, Terry; Clond, Morgan
2016-01-01
Prior research indicates elevated but subclinical posttraumatic stress disorder (PTSD) symptoms as a risk factor for a later diagnosis of PTSD. This study examined the progression of symptoms in 21 subclinical veterans. Participants were randomized into a treatment as usual (TAU) wait-list group and an experimental group, which received TAU plus six sessions of clinical emotional freedom techniques (EFT). Symptoms were assessed using the PCL-M (Posttraumatic Checklist-Military) on which a score of 35 or higher indicates increased risk for PTSD. The mean pretreatment score of participants was 39 ± 8.7, with no significant difference between groups. No change was found in the TAU group during the wait period. Afterward, the TAU group received an identical clinical EFT protocol. Posttreatment groups were combined for analysis. Scores declined to a mean of 25 (-64%, P < .0001). Participants maintained their gains, with mean three-month and six-month follow-up PCL-M scores of 27 (P < .0001). Similar reductions were noted in the depth and breadth of psychological conditions such as anxiety. A Cohen's d = 1.99 indicates a large treatment effect. Reductions in traumatic brain injury symptoms (P = .045) and insomnia (P = .004) were also noted. Symptom improvements were similar to those assessed in studies of PTSD-positive veterans. EFT may thus be protective against an increase in symptoms and a later PTSD diagnosis. As a simple and quickly learned self-help method, EFT may be a clinically useful element of a resiliency program for veterans and active-duty warriors. Copyright © 2016 Elsevier Inc. All rights reserved.
A 2009 survey of the Australasian clinical medical physics and biomedical engineering workforce.
Round, W Howell
2010-06-01
A survey of the Australasian clinical medical physics and biomedical engineering workforce was carried out in 2009 following on from a similar survey in 2006. 621 positions (equivalent to 575 equivalent full time (EFT) positions) were captured by the survey. Of these 330 EFT were in radiation oncology physics, 45 EFT were in radiology physics, 42 EFT were in nuclear medicine physics, 159 EFT were in biomedical engineering and 29 EFT were attributed to other activities. The survey reviewed the experience profile, the salary levels and the number of vacant positions in the workforce for the different disciplines in each Australian state and in New Zealand. Analysis of the data shows the changes to the workforce over the preceding 3 years and identifies shortfalls in the workforce.
Minimally nonlocal nucleon-nucleon potentials with chiral two-pion exchange including Δ resonances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piarulli, M.; Girlanda, L.; Schiavilla, R.
In this study, we construct a coordinate-space chiral potential, including Δ-isobar intermediate states in its two-pion-exchange component up to order Q 3 (Q denotes generically the low momentum scale). The contact interactions entering at next-to-leading and next-to-next-to-next-to-leading orders (Q 2 and Q 4, respectively) are rearranged by Fierz transformations to yield terms at most quadratic in the relative momentum operator of the two nucleons. The low-energy constant multiplying these contact interactions are fitted to the 2013 Granada database, consisting of 2309 pp and 2982 np data (including, respectively, 148 and 218 normalizations) in the laboratory-energy range 0–300 MeV. For themore » total 5291 $pp$ and $np$ data in this range, we obtain a Χ 2 /datum of roughly 1.3 for a set of three models characterized by long- and short-range cutoffs, R L and R S respectively, ranging from (R L,R S)=(1.2,0.8) fm down to (0.8,0.6) fm. The long-range (short-range) cutoff regularizes the one- and two-pion exchange (contact) part of the potential.« less
Minimally nonlocal nucleon-nucleon potentials with chiral two-pion exchange including Δ resonances
Piarulli, M.; Girlanda, L.; Schiavilla, R.; ...
2015-02-26
In this study, we construct a coordinate-space chiral potential, including Δ-isobar intermediate states in its two-pion-exchange component up to order Q 3 (Q denotes generically the low momentum scale). The contact interactions entering at next-to-leading and next-to-next-to-next-to-leading orders (Q 2 and Q 4, respectively) are rearranged by Fierz transformations to yield terms at most quadratic in the relative momentum operator of the two nucleons. The low-energy constant multiplying these contact interactions are fitted to the 2013 Granada database, consisting of 2309 pp and 2982 np data (including, respectively, 148 and 218 normalizations) in the laboratory-energy range 0–300 MeV. For themore » total 5291 $pp$ and $np$ data in this range, we obtain a Χ 2 /datum of roughly 1.3 for a set of three models characterized by long- and short-range cutoffs, R L and R S respectively, ranging from (R L,R S)=(1.2,0.8) fm down to (0.8,0.6) fm. The long-range (short-range) cutoff regularizes the one- and two-pion exchange (contact) part of the potential.« less
NASA Astrophysics Data System (ADS)
Kłos, B.; Ciepał, I.; Jamróz, B.; Khatri, G.; Kistryn, S.; Kozela, A.; Magiera, A.; Parol, W.; Skwira-Chalot, I.; Stephan, E.
2014-08-01
An experiment to investigate the 1H( d, pp) n breakup reaction using a deuteron beam of 340, 380 and 400 MeV and the WASA detector has been performed at the Cooler Synchrotron COSY-Jülich. The main goal was the detailed study of various aspects of few-nucleon dynamics in the medium energy region, with particular emphasis on relativistic effects and their interplay with three nucleon forces. These effects become more important with increasing available energy in the three nucleon system. Therefore the investigations at high energies are crucial to understand their nature. The almost 4 π geometry of the WASA detector gives an unique possibility to study various aspects of dynamics of processes in the three-nucleon reaction. Preliminary results obtained using the WASA detector are presented.
Nonperturbative derivation of the interaction potential of static nucleons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Izmailov, A.F.; Kessel', A.R.; Fainberg, V.Y.
1989-05-01
A new approach is used to calculate the interaction potential of nucleons which describes virtual processes of exchange of scalar and pseudoscalar mesons in all orders in the nucleon{endash}meson local coupling constant. The theory contains a natural parameter---a limiting momentum {ital p}{sub {ital m}}. The nucleon{endash}nucleon potential of scalar mesodynamics for various values of {ital p}{sub {ital m}} reproduces accurately the well known phenomenological potentials, such as the Hamada{endash}Johnston potential, the Reid soft-core potential, and the de Toureil{endash}Sprung supersoft-core potential.{sup 15} In pseudoscalar mesodynamics, it has been possible to reproduce completely the behavior of the empirical tensor potential. The shapemore » of the central potential at all distances is reproduced in the states {tau}=0, {sigma}=0 and {tau}=0, {sigma}=1, and at intermediate and large distances in the states {tau}=1, {sigma}=0 and {tau}=1, {sigma}=1.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nicola, Marcello Santo
Using data from Fermilab xed-target experiment E769, we have measured particleantiparticle production asymmetries for Λ 0 hyperons in π ± - nucleon interactions, K ± - nucleon interactions and p - nucleon interactions at 250 GeV/c. The asymmetries are measured as functions of Feynman-x (x f ) and p T 2 over the ranges 0 ≤ p T 2 ≤ 4(GeV/c) 2 and -0.12 ≤ x F ≤ 0.12 (for positive beam) and 0 ≤ p T 2 ≤ 10(GeV/c) 2 and -0.16 ≤ x F ≤ 0:.0 for the negative beam. We find substantial asymmetries, even at x Fmore » = 0. We also observe leading-particle-type asymmetries which qualitatively agree with theoretical predictions.« less
Leading order relativistic chiral nucleon-nucleon interaction
NASA Astrophysics Data System (ADS)
Ren, Xiu-Lei; Li, Kai-Wen; Geng, Li-Sheng; Long, Bingwei; Ring, Peter; Meng, Jie
2018-01-01
Motivated by the successes of relativistic theories in studies of atomic/molecular and nuclear systems and the need for a relativistic chiral force in relativistic nuclear structure studies, we explore a new relativistic scheme to construct the nucleon-nucleon interaction in the framework of covariant chiral effective field theory. The chiral interaction is formulated up to leading order with covariant power counting and a Lorentz invariant chiral Lagrangian. We find that the relativistic scheme induces all six spin operators needed to describe the nuclear force. A detailed investigation of the partial wave potentials shows a better description of the {}1S0 and {}3P0 phase shifts than the leading order Weinberg approach, and similar to that of the next-to-leading order Weinberg approach. For the other partial waves with angular momenta J≥slant 1, the relativistic results are almost the same as their leading order non-relativistic counterparts. )
Complete set of deuteron analyzing powers from d ⃗p elastic scattering at 190 MeV/nucleon
NASA Astrophysics Data System (ADS)
Sekiguchi, K.; Witała, H.; Akieda, T.; Eto, D.; Kon, H.; Wada, Y.; Watanabe, A.; Chebotaryov, S.; Dozono, M.; Golak, J.; Kamada, H.; Kawakami, S.; Kubota, Y.; Maeda, Y.; Miki, K.; Milman, E.; Ohkura, A.; Sakai, H.; Sakaguchi, S.; Sakamoto, N.; Sasano, M.; Shindo, Y.; Skibiński, R.; Suzuki, H.; Tabata, M.; Uesaka, T.; Wakasa, T.; Yako, K.; Yamamoto, T.; Yanagisawa, Y.; Yasuda, J.
2017-12-01
All deuteron analyzing powers for elastic deuteron-proton (d p ) scattering have been measured with a polarized deuteron beam at 186.6 MeV/nucleon. They are compared with results of three-nucleon Faddeev calculations based on the standard, high-precision nucleon-nucleon (N N ) potentials alone or combined with commonly used three-nucleon force (3 N F ) models such as the Tucson-Melbourne '99 or the Urbana IX. Predicted 3 N F effects localized at backward angles are supported only partially by the data. The data are also compared to predictions based on locally regularized chiral N N potentials. An estimation of theoretical truncation uncertainties in the consecutive orders of chiral expansion suggests that the observed discrepancies between this modern theory and the data could probably be explained by including chiral 3 N F 's in future calculations. A systematic comparison to the deuteron analyzing power data previously taken at incident energies from 70 to 294 MeV/nucleon clearly shows that not only the cross section but also the analyzing powers reveal growing 3 N F effects when the three-nucleon system energy is increased.
Aspects of Particle Physics Beyond the Standard Model
NASA Astrophysics Data System (ADS)
Lu, Xiaochuan
This dissertation describes a few aspects of particles beyond the Standard Model, with a focus on the remaining questions after the discovery of a Standard Model-like Higgs boson. In specific, three topics are discussed in sequence: neutrino mass and baryon asymmetry, naturalness problem of Higgs mass, and placing constraints on theoretical models from precision measurements. First, the consequence of the neutrino mass anarchy on cosmology is studied. Attentions are paid in particular to the total mass of neutrinos and baryon asymmetry through leptogenesis. With the assumption of independence among mass matrix entries in addition to the basis independence, Gaussian measure is the only choice. On top of Gaussian measure, a simple approximate U(1) flavor symmetry makes leptogenesis highly successful. Correlations between the baryon asymmetry and the light-neutrino quantities are investigated. Also discussed are possible implications of recently suggested large total mass of neutrinos by the SDSS/BOSS data. Second, the Higgs mass implies fine-tuning for minimal theories of weak-scale supersymmetry (SUSY). Non-decoupling effects can boost the Higgs mass when new states interact with the Higgs, but new sources of SUSY breaking that accompany such extensions threaten naturalness. I will show that two singlets with a Dirac mass can increase the Higgs mass while maintaining naturalness in the presence of large SUSY breaking in the singlet sector. The modified Higgs phenomenology of this scenario, termed "Dirac NMSSM", is also studied. Finally, the sensitivities of future precision measurements in probing physics beyond the Standard Model are studied. A practical three-step procedure is presented for using the Standard Model effective field theory (SM EFT) to connect ultraviolet (UV) models of new physics with weak scale precision observables. With this procedure, one can interpret precision measurements as constraints on the UV model concerned. A detailed explanation is given for calculating the effective action up to one-loop order in a manifestly gauge covariant fashion. This covariant derivative expansion method dramatically simplifies the process of matching a UV model with the SM EFT, and also makes available a universal formalism that is easy to use for a variety of UV models. A few general aspects of RG running effects and choosing operator bases are discussed. Mapping results are provided between the bosonic sector of the SM EFT and a complete set of precision electroweak and Higgs observables to which present and near future experiments are sensitive. Many results and tools which should prove useful to those wishing to use the SM EFT are detailed in several appendices.
Systematics of ground state multiplets of atomic nuclei in the delta-interaction approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Imasheva, L. T.; Ishkhanov, B. S.; Stepanov, M. E., E-mail: stepanov@depni.sinp.msu.ru
2015-12-15
Pairing forces between nucleons in an atomic nucleus strongly influence its structure. One of the manifestations of pair interaction is the ground state multiplet (GSM) formation in the spectrum of low-lying excited states of even–even nuclei. The value of GSM splitting is determined by the value of pair interaction of nucleons; for each isotope, it can be estimated on the basis of experimental nuclear masses. The quality of this estimate is characterized by the degree of reproduction of GSM levels in the nucleus. The GSM systematics in even–even nuclei with a pair of identical nucleons in addition to the filledmore » nuclear core is considered on the basis of delta interaction.« less
Sze, Yan Yan; Stein, Jeffrey S; Bickel, Warren K; Paluch, Rocco A; Epstein, Leonard H
2017-07-01
Obesity is associated with steep discounting of the future and increased food reinforcement. Episodic future thinking (EFT), a type of prospective thinking, has been observed to reduce delay discounting (DD) and improve dietary decision making. In contrast, negative income shock (i.e., abrupt transitions to poverty) has been shown to increase discounting and may worsen dietary decision-making. Scalability of EFT training and protective effects of EFT against simulated negative income shock on DD and demand for food were assessed. In two experiments we showed online-administered EFT reliably reduced DD. Furthermore, EFT reduced DD and demand for fast foods even when challenged by negative income shock. Our findings suggest EFT is a scalable intervention that has implications for improving public health by reducing discounting of the future and demand for high energy dense food.
A 2012 survey of the Australasian clinical medical physics and biomedical engineering workforce.
Round, W H
2013-06-01
A survey of the medical physics and biomedical engineering workforce in Australia and New Zealand was carried out in 2012 following on from similar surveys in 2009 and 2006. 761 positions (equivalent to 736 equivalent full time (EFT) positions) were captured by the survey. Of these, 428 EFT were in radiation oncology physics, 63 EFT were in radiology physics, 49 EFT were in nuclear medicine physics, 150 EFT were in biomedical engineering and 46 EFT were attributed to other activities. The survey reviewed the experience profile, the salary levels and the number of vacant positions in the workforce for the different disciplines in each Australian state and in New Zealand. Analysis of the data shows the changes to the workforce over the preceding 6 years and identifies shortfalls in the workforce.
Liu, Bing; Persons, Logan; Lee, Lynda; de Boer, Piet A. J.
2015-01-01
SUMMARY Escherichia coli FtsN is a bitopic membrane protein that is essential for triggering active cell constriction. A small periplasmic subdomain (EFtsN) is required and sufficient for function, but its mechanism of action is unclear. We isolated extragenic EFtsN*-suppressing mutations that restore division in cells producing otherwise non-functional variants of FtsN. These mapped to the IC domain of FtsA in the cytoplasm and to small subdomains of the FtsB and FtsL proteins in the periplasm. All FtsB and FtsL variants allowed survival without EFtsN, but many then imposed a new requirement for interaction between the cytoplasmic domain of FtsN (NFtsN) with FtsA. Alternatively, variants of FtsA, FtsB or FtsL acted synergistically to allow cell division in the complete absence of FtsN. Strikingly, moreover, substitution of a single residue in FtsB (E56) proved sufficient to rescue ΔftsN cells as well. In FtsN+ cells, EFtsN*-suppressing mutations promoted cell fission at an abnormally small cell size, and caused cell shape and integrity defects under certain conditions. This and additional evidence support a model in which FtsN acts on either side of the membrane to induce a conformational switch in both FtsA and the FtsBLQ subcomplex to derepress septal peptidoglycan synthesis and membrane invagination. PMID:25496160
Symmetry energies for A =24 and 48 and the USD and KB3 shell model Hamiltonians
NASA Astrophysics Data System (ADS)
Kingan, A.; Neergârd, K.; Zamick, L.
2017-12-01
Calculations in the sd and pf shells reported some time ago by Satuła et al. [Phys. Lett. B 407, 103 (1997), 10.1016/S0370-2693(97)00711-9] are redone for an extended analysis of the results. As in the original work, we do calculations for one mass number in each shell and consider in each case the sequence of lowest energies for isospins 0, 2, and 4, briefly the symmetry spectrum. Following further the original work, we study how this spectrum changes when parts of the two-nucleon interaction are turned off. The variation of its width is explored in detail. A differential combination ɛW of the three energies was taken in the original work as a measure of the so-called Wigner term in semiempirical mass formulas, and it was found to decrease drastically when the two-nucleon interaction in the channel of zero isospin is turned off. Our analysis shows that the width of the symmetry spectrum experiences an equally drastic decrease, which can be explained qualitatively in terms of schematic approximations. We therefore suggest that the decrease of ɛW be seen mainly as a side effect of a narrowing of the symmetry spectrum rather than an independent manifestation of the two-nucleon interaction in the channel of zero isospin.
Quantum Monte Carlo methods for nuclear physics
Carlson, J.; Gandolfi, S.; Pederiva, F.; ...
2015-09-09
Quantum Monte Carlo methods have proved valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments, and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. The nuclear interactions and currents are reviewed along with a description of the continuum quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit,more » and three-body interactions. A variety of results are presented, including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. Low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars are also described. Furthermore, a coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.« less
Quantum Monte Carlo methods for nuclear physics
Carlson, Joseph A.; Gandolfi, Stefano; Pederiva, Francesco; ...
2014-10-19
Quantum Monte Carlo methods have proved very valuable to study the structure and reactions of light nuclei and nucleonic matter starting from realistic nuclear interactions and currents. These ab-initio calculations reproduce many low-lying states, moments and transitions in light nuclei, and simultaneously predict many properties of light nuclei and neutron matter over a rather wide range of energy and momenta. We review the nuclear interactions and currents, and describe the continuum Quantum Monte Carlo methods used in nuclear physics. These methods are similar to those used in condensed matter and electronic structure but naturally include spin-isospin, tensor, spin-orbit, and three-bodymore » interactions. We present a variety of results including the low-lying spectra of light nuclei, nuclear form factors, and transition matrix elements. We also describe low-energy scattering techniques, studies of the electroweak response of nuclei relevant in electron and neutrino scattering, and the properties of dense nucleonic matter as found in neutron stars. A coherent picture of nuclear structure and dynamics emerges based upon rather simple but realistic interactions and currents.« less
Some highlights in few-body nuclear physics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holt, R. J.
2000-12-07
During the past five years, there have been tremendous advances in both experiments and theoretical calculations in few-body nuclear systems. Advances in technology have permitted experiments of unprecedented accuracy. Jefferson Laboratory has begun operation and the first round of experimental results have become available. New polarization techniques have been exploited at a number of laboratories, in particular, at Jefferson Lab, IUCF, RIKEN, NIKHEF, Mainz, MIT-Bates and HERMES. Some of these results will be shown here. In addition, there have been tremendous advances in few-body theory. Five modern two-nucleon potentials have which describe the nucleon-nucleon data extremely well have become available.more » A standard model of nuclear physics based on these two nucleon potentials as well as modern three-nucleon forces has emerged. This standard model has enjoyed tremendous success in the few body systems. Exact three-body calculations have been extended into the continuum in order to take full advantage of scattering data in advancing our understanding of the the few-nucleon system. In addition, the application of chiral symmetry has become an important constraint on nucleon-nucleon as well as three-nucleon forces. As a result of all these efforts, we have seen rapid developments in the three-body force. Despite these advances, there remain some extremely important open issues: (1) What is the role of quarks and gluons in nuclear structure; (2) Can we distinguish meson exchange from quark interchange; (3) Is few-body theory sufficient to describe simultaneously the mass 2, 3 and 4 form factors; (4) What is the isospin and spin dependence of the three-body force; (5) Are there medium modifications for nucleons and mesons in nuclei; (6) Is there an enhancement of antiquarks or pions in nuclei related to the binding; and (7) Are short range correlations observable in nuclei? In this paper the author summarizes the status of our understanding of these issues.« less
Light neutron-rich hypernuclei from the importance-truncated no-core shell model
NASA Astrophysics Data System (ADS)
Wirth, Roland; Roth, Robert
2018-04-01
We explore the systematics of ground-state and excitation energies in singly-strange hypernuclei throughout the helium and lithium isotopic chains - from He5Λ to He11Λ and from Li7Λ to Li12Λ - in the ab initio no-core shell model with importance truncation. All calculations are based on two- and three-baryon interaction from chiral effective field theory and we employ a similarity renormalization group transformation consistently up to the three-baryon level to improve the model-space convergence. While the absolute energies of hypernuclear states show a systematic variation with the regulator cutoff of the hyperon-nucleon interaction, the resulting neutron separation energies are very stable and in good agreement with available data for both nucleonic parents and their daughter hypernuclei. We provide predictions for the neutron separation energies and the spectra of neutron-rich hypernuclei that have not yet been observed experimentally. Furthermore, we find that the neutron drip lines in the helium and lithium isotopic chains are not changed by the addition of a hyperon.
Identification of nuclear effects in neutrino-carbon interactions at low three-momentum transfer
Rodrigues, P. A.
2016-02-17
Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current νμ interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced populationmore » of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Furthermore, improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.« less
Advancing the Theory of Nuclear Reactions with Rare Isotopes: From the Laboratory to the Cosmos
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elster, Charlotte
2015-06-01
The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. Ohio University concentrates its efforts on the first part of the mission. Since direct measurements are often not feasible, indirect methods, e.g. (d,p) reactions, should be used. Those (d,p) reactions may be viewed as three-body reactions and described with Faddeev techniques. Faddeev equations in momentum space have a long tradition of utilizing separable interactions in ordermore » to arrive at sets of coupled integral equations in one variable. While there exist several separable representations for the nucleon-nucleon interaction, the optical potential between a neutron (proton) and a nucleus is not readily available in separable form. For this reason we first embarked in introducing a separable representation for complex phenomenological optical potentials of Woods-Saxon type.« less
Episodic Future Thinking in Generalized Anxiety Disorder
Wu, Jade Q.; Szpunar, Karl K.; Godovich, Sheina A.; Schacter, Daniel L.; Hofmann, Stefan G.
2015-01-01
Research on future-oriented cognition in generalized anxiety disorder (GAD) has primarily focused on worry, while less is known about the role of episodic future thinking (EFT), an imagery-based cognitive process. To characterize EFT in this disorder, we used the experimental recombination procedure, in which 21 GAD and 19 healthy participants simulated positive, neutral and negative novel future events either once or repeatedly, and rated their phenomenological experience of EFT. Results showed that healthy controls spontaneously generated more detailed EFT over repeated simulations. Both groups found EFT easier to generate after repeated simulations, except when GAD participants simulated positive events. They also perceived higher plausibility of negative—not positive or neutral—future events than did controls. These results demonstrate a negativity bias in GAD individuals’ episodic future cognition, and suggest their relative deficit in generating vivid EFT. We discuss implications for the theory and treatment of GAD. PMID:26398003
Equation of state of asymmetric nuclear matter using re-projected nucleon–nucleon potentials
NASA Astrophysics Data System (ADS)
Asadi Aghbolaghi, Z.; Bigdeli, M.
2018-06-01
In this paper, we have calculated the equation of state of asymmetric nuclear matter using the lowest order constrained variational approach and Argonne family potentials with and without three-nucleon interaction (TNI) contribution. In particular, we have used the AV18 potential and the re-projected potentials, AV8‧, and AV6‧. We have also calculated the saturation properties of symmetric nuclear matter, and the nuclear symmetry energy using AV18+TNI, AV8‧+TNI and AV6‧+TNI potentials. The inclusion of TNI has modified the agreement with experiment. We have also made a comparison between our results and those of other many-body calculations.
The feminist/emotionally focused therapy practice model: an integrated approach for couple therapy.
Vatcher, C A; Bogo, M
2001-01-01
Emotionally focused therapy (EFT) is a well-developed, empirically tested practice model for couple therapy that integrates systems, experiential, and attachment theories. Feminist family therapy theory has provided a critique of biased assumptions about gender at play in traditional family therapy practice and the historical absence of discussions of power in family therapy theory. This article presents an integrated feminist/EFT practice model for use in couple therapy, using a case from practice to illustrate key concepts. Broadly, the integrated model addresses gender roles and individual emotional experience using a systemic framework for understanding couple interaction. The model provides practitioners with a sophisticated, comprehensive, and relevant practice approach for working with the issues and challenges emerging for contemporary heterosexual couples.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Knyr, V. A.; Neudatchin, V. G.; Khokhlov, N. A.
Data of a partial-wave analysis of nucleon-nucleon scattering at energies of up to E{sub lab} = 3 GeV (lower partial waves) and the properties of the deuteron are described within the relativistic optical model based on deep attractive quasipotentials involving forbidden states (as exemplified by the Moscow potential). Partial-wave potentials are derived by the inverse-scattering-problem method based on the Marchenko equation by using present-day data from the partial-wave analysis of nucleon-nucleon scattering at energies of up to 3 GeV. Channel coupling is taken into account. The imaginary parts of the potentials are deduced from the phase equation of the variable-phasemore » approach. The general situation around the manifestation of quark effects in nucleon-nucleon interaction is discussed.« less
The Method of Unitary Clothing Transformations in the Theory of Nucleon-Nucleon Scattering
NASA Astrophysics Data System (ADS)
Dubovyk, I.; Shebeko, O.
2010-12-01
The clothing procedure, put forward in quantum field theory (QFT) by Greenberg and Schweber, is applied for the description of nucleon-nucleon ( N- N) scattering. We consider pseudoscalar ( π and η), vector ( ρ and ω) and scalar ( δ and σ) meson fields interacting with 1/2 spin ( N and {bar{N}}) fermion ones via the Yukawa-type couplings to introduce trial interactions between “bare” particles. The subsequent unitary clothing transformations are found to express the total Hamiltonian through new interaction operators that refer to particles with physical (observable) properties, the so-called clothed particles. In this work, we are focused upon the Hermitian and energy-independent operators for the clothed nucleons, being built up in the second order in the coupling constants. The corresponding analytic expressions in momentum space are compared with the separate meson contributions to the one-boson-exchange potentials in the meson theory of nuclear forces. In order to evaluate the T matrix of the N- N scattering we have used an equivalence theorem that enables us to operate in the clothed particle representation (CPR) instead of the bare particle representation with its large amount of virtual processes. We have derived the Lippmann-Schwinger type equation for the CPR elements of the T-matrix for a given collision energy in the two-nucleon sector of the Hilbert space {mathcal{H}} of hadronic states.
Cho, Kyoung Im; Jo, Eun Ah; Cho, Sang Hoon; Kim, Bo Hyun
2017-06-01
Epicardial adipose tissues reflecting visceral fat accumulations of the heart are associated with metabolic syndrome (MetS) and can be a predictor of other cardiometabolic diseases. It can adversely influence autonomic nervous system (ANS) of heart. Heart rate recovery (HRR) is an easy method for measuring ANS dysfunction. The purpose of this study was to determine whether epicardial fat thickness (EFT) and nonalcoholic fatty liver disease (NAFLD) are related to HRR in patients with MetS. We enrolled 772 consecutive patients from a health-screening center who underwent abdominal ultrasonography, treadmill test, and cardiac echocardiography. EFT using echocardiography and HRR by symptom-limited exercise testing was assessed. According to the presence of MetS and NAFLD, patients were classified into the four groups. In NAFLD patients, EFT was higher and HRR was lower, especially in patients with MetS and NAFLD, compared to non-MetS participants without NAFLD (MetS with NAFLD, EFT 7.5 ± 4.4 mm, HRR 31.9 ± 12.7; MetS without NAFLD, EFT 4.9 ± 3.0 mm, HRR 39.5 ± 11.1; non-MetS with NAFLD, EFT 5.9 ± 3.6 mm, HRR 36.6 ± 12.7; and non-MetS without NAFLD, EFT 4.4 ± 3.5 mm, HRR 43.4 ± 14.5, p < 0.001). Patients with severe liver steatosis (LS) showed significantly higher EFT than those with moderate LS (14.2 ± 2.0 vs. 7.5 ± 3.1 mm, P < 0.001), and EFT was positively correlated with severity of LS (r = 0.431, P < 0.001). HRR was significantly correlated with EFT (r = -0.386, P < 0.001) and severity of LS (r = -0.324, P < 0.001). EFT and NAFLD were significantly correlated with HRR in patients with MetS and they may be highly related to increased cardiovascular risk. These results suggest a cross-link among EFT, NAFLD, and cardiac autonomic dysfunction in patients with MetS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lepekhin, F. G., E-mail: lepfed@yandex.ru; Tkach, L. N.
2011-05-15
Transverse-momentum distributions of doubly charged fragments of sulfur and lead nuclei having energies of 200 and 160 GeV per nucleon and interacting with nuclei in a track emulsion were investigated. No trace of compression or heating of nuclear matter in the interaction of these nuclei with track-emulsion nuclei was revealed experimentally. Transverse momenta of fragments of relativistic nuclei were found to obey a normal distribution that corresponds to a degenerate momentum distribution of nucleons in the ground state of a nucleus before its interaction with a track-emulsion nucleus. There is no piece of evidence that fragments of relativistic nuclei originatemore » from some excited state of an intermediate nucleus. This picture of the fragmentation of relativistic nuclei complies with the naive parton model proposed by Feynman and Gribov. In summary, the fragmentation of relativistic nuclei at energies of 160 and 200 GeV per nucleon is cold and fast.« less
SIDDHARTA results and implications of the results on antikaon-nucleon interaction
NASA Astrophysics Data System (ADS)
Marton, J.; Bazzi, M.; Beer, G.; Berucci, C.; Bellotti, G.; Bosnar, D.; Bragadireanu, A. M.; Cargnelli, M.; Clozza, A.; Curceanu, C.; Butt, A. Dawood; Fiorini, C.; Ghio, F.; Guaraldo, C.; Hayano, R.; Iliescu, M.; Iwasaki, M.; Sandri, P. Levi; Okada, S.; Pietreanu, D.; Piscicchia, K.; Vidal, A. Romero; Scordo, A.; Shi, H.; Sirghi, D. L.; Sirghi, F.; Tatsuno, H.; Doce, O. Vazquez; Widmann, E.; Zmeskal, J.
2016-05-01
The interaction of antikaons (K-) with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics. There are important open questions like the existence of antikaon nuclear bound states like the prototype system being K- pp. Unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states in light kaonic atoms like kaonic hydrogen and helium isotopes. In the SIDDHARTA experiment at the electron-positron collider DAΦNE of LNF-INFN we measured the most precise values of the strong interaction observables, i.e. the strong interaction on the 1s ground state of the electromagnetically bound K-p atom leading to energy shift and broadening of the 1s state. The SIDDHARTA result triggered new theoretical work, which achieved major progress in the understanding of the low-energy strong interaction with strangeness reflected by the antikaon-nucleon scattering lengths calculated with the K--proton amplitudes constrained by the SIDDHARTA data. The most important open question is the experimental determination of the hadronic energy shift and width of kaonic deuterium which is planned by the SIDDHARTA-2 Collaboration.
Suh, Jin Woo; Chung, Sun Yong; Kim, Sang Young; Lee, Jung Hwan; Kim, Jong Woo
2015-01-01
Background. The Emotional Freedom Technique (EFT) is a meridian-based psychological therapy. The present clinical trial investigates the effectiveness of EFT as a new treatment option for Hwabyung (HB) patients experiencing anger and compares the efficacy to the Progressive Muscle Relaxation (PMR), the conventional meditation technique. Methods. The EFT and progressive muscle relaxation (PMR) methods were performed on 27 HB patients, and their capacities to alleviate anxiety, anger, and emotional status were compared. After a 4-week program, a survey was conducted; patients then completed a self-training program for 4 weeks, followed by a second survey. Results. During the initial 4 weeks, the EFT group experienced a significant decrease in the HB symptom scale, anger state, and paranoia ideation (p < 0.05). Over the entire 9-week interval, there were significant decreases in the HB symptom scale, anxiety state, anger state, anger trait, somatization, anxiety, hostility, and so on in EFT group (p < 0.05). Conclusion. The EFT group showed improved psychological symptoms and physical symptoms greater than those observed in the PMR group. EFT more effectively alleviated HB symptoms compared to PMR. EFT group showed better maintenance during self-training, suggesting good model of self-control treatment in HB patients. PMID:26539218
On the Relativistic Separable Functions for the Breakup Reactions
NASA Astrophysics Data System (ADS)
Bondarenko, Serge G.; Burov, Valery V.; Rogochaya, Elena P.
2018-02-01
In the paper the so-called modified Yamaguchi function for the Bethe-Salpeter equation with a separable kernel is discussed. The type of the functions is defined by the analytic stucture of the hadron current with breakup - the reactions with interacting nucleon-nucleon pair in the final state (electro-, photo-, and nucleon-disintegration of the deuteron).
Studies of the nucleon structure in back-to-back SIDIS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Avakian, Harut
2016-03-01
The Deep Inelastic Scattering (DIS) proved to be a great tool in testing of the theory of strong interactions, which was a major focus in last decades. Semi-Inclusive DIS (SIDIS), with detection of an additional hadron allowed first studies of 3D structure of the nucleon, moving the main focus from testing the QCD to understanding of strong interactions and quark gluon dynamics to address a number of puzzles accumulated in recent years. Detection of two hadrons in SIDIS, which is even more complicated, provides access to details of quark gluon interactions inaccessible in single-hadron SIDIS, providing a new avenue tomore » study the complex nucleon structure. Large acceptance of the Electron Ion Collider, allowing detection of two hadrons, produced back-to-back in the current and target fragmentation regions, combined with clear separation of two regions, would provide a unique possibility to study the nucleon structure in target fragmentation region, and correlations of target and current fragmentation regions.« less
A new single-particle basis for nuclear many-body calculations
NASA Astrophysics Data System (ADS)
Puddu, G.
2017-10-01
Predominantly, harmonic oscillator single-particle wave functions are the preferred choice for a basis in ab initio nuclear many-body calculations. These wave-functions, although very convenient in order to evaluate the matrix elements of the interaction in the laboratory frame, have too fast a fall-off at large distances. In the past, as an alternative to the harmonic oscillator, other single-particle wave functions have been proposed. In this work, we propose a new single-particle basis, directly linked to nucleon-nucleon interaction. This new basis is orthonormal and complete, has the proper asymptotic behavior at large distances and does not contain the continuum which would pose severe convergence problems in nuclear many body calculations. We consider the newly proposed NNLO-opt nucleon-nucleon interaction, without any renormalization. We show that, unlike other bases, this single-particle representation has a computational cost similar to the harmonic oscillator basis with the same space truncation and it gives lower energies for 6He and 6Li.
Multinucleon pion absorption on {sup 4}He into the pppn final state
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lehmann, A.; Backenstoss, G.; Koehler, J.
1997-10-01
Results from a 4{pi} solid angle measurement of the reaction {pi}{sup +4}He{r_arrow}pppn at incident pion energies of T{sub {pi}{sup +}}= 70, 118, 162, 239, and 330 MeV are presented. Integrated cross sections are given for the reactions where three nucleons participate, leading to energetic (ppp) or (ppn) final states, and for states where four nucleons are involved (pppn). The two three-nucleon absorption modes were investigated in particular, and an energy dependent isospin ratio of the cross sections of {sigma}{sub ppn}/ {sigma}{sub ppp}=3.6{plus_minus}1.3, 2.6 {plus_minus}0.5, 1.8{plus_minus}0.3, 1.4{plus_minus} 0.2, and 1.8{plus_minus}0.6 was determined from 70 to 330 MeV. The differential cross sectionsmore » were described by a complete set of eight independent variables and compared to simple cascade and phase space models. From this analysis the contributions from initial state interactions to the multinucleon absorption cross sections were found to be more important at higher pion energies, while those from final state interactions are stronger at lower energies. However, both mechanisms combined were found to account for not more than one-third of the total pppn multinucleon yield. The remaining strength is reasonably well reproduced by phase space models, but shows a dependence on the incident pion{close_quote}s orbital angular momentum. The isospin structure of the (ppp) and (ppn) final states is not understood, nor are some structures in their distributions. The four-nucleon yield (pppn) was found to be weak (1{endash}8{percent} of the total absorption cross section) and shows no evidence for a {open_quotes}double- {Delta}{close_quotes} excitation. {copyright} {ital 1997} {ital The American Physical Society}« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Del Dotto, Alessio; Pace, Emanuele; Salme, Giovanni
Poincare covariant definitions for the spin-dependent spectral function and for the momentum distributions within the light-front Hamiltonian dynamics are proposed for a three-fermion bound system, starting from the light-front wave function of the system. The adopted approach is based on the Bakamjian–Thomas construction of the Poincaré generators, which allows one to easily import the familiar and wide knowledge on the nuclear interaction into a light-front framework. The proposed formalism can find useful applications in refined nuclear calculations, such as those needed for evaluating the European Muon Collaboration effect or the semi-inclusive deep inelastic cross sections with polarized nuclear targets, sincemore » remarkably the light-front unpolarized momentum distribution by definition fulfills both normalization and momentum sum rules. As a result, also shown is a straightforward generalization of the definition of the light-front spectral function to an A-nucleon system.« less
Del Dotto, Alessio; Pace, Emanuele; Salme, Giovanni; ...
2017-01-10
Poincare covariant definitions for the spin-dependent spectral function and for the momentum distributions within the light-front Hamiltonian dynamics are proposed for a three-fermion bound system, starting from the light-front wave function of the system. The adopted approach is based on the Bakamjian–Thomas construction of the Poincaré generators, which allows one to easily import the familiar and wide knowledge on the nuclear interaction into a light-front framework. The proposed formalism can find useful applications in refined nuclear calculations, such as those needed for evaluating the European Muon Collaboration effect or the semi-inclusive deep inelastic cross sections with polarized nuclear targets, sincemore » remarkably the light-front unpolarized momentum distribution by definition fulfills both normalization and momentum sum rules. As a result, also shown is a straightforward generalization of the definition of the light-front spectral function to an A-nucleon system.« less
Emergent spacetime according to effective field theory: From top-down and bottom-up
NASA Astrophysics Data System (ADS)
Crowther, Karen
2013-08-01
The framework of effective field theory (EFT) is a natural one in which to understand the claim that the spacetime of general relativity (GR) is an emergent low-energy phenomenon. I argue for a pragmatic understanding of EFT, given that the appropriate conception of emergence it suggests is necessarily epistemological in a sense. Analogue models of spacetime are examples of the top-down approach to EFT. They offer concrete illustrations of spacetime emergent within an EFT, and lure us toward a strong analogy between condensed matter physics and GR. I argue that we should be wary of this strong analogy, not least because the pragmatic view of EFT places limits on how much we can legitimately draw from it. On the other hand, programs that treat GR as an EFT and calculate quantum corrections are an example of the bottom-up approach and are explicitly pragmatic in character. I explore what we may learn about the nature of emergent spacetime by comparing these two approaches.
Stein, Jeffrey S; Tegge, Allison N; Turner, Jamie K; Bickel, Warren K
2018-04-01
Episodic future thinking (EFT), an intervention involving mental simulation of future events, has been shown to reduce both delay discounting and cigarette self-administration. In the present study, we extended these findings by showing that EFT in a web-based sample of smokers reduces delay discounting and intensity of demand for cigarettes (ad libitum consumption) in a hypothetical purchase task. No effect was observed on elasticity of demand (sensitivity to price) or cigarette craving. We also explored whether demand characteristics (specifically, the "good-subject" effect) might be responsible for observed effects. EFT participants were significantly better able than control participants to discern the experimental hypothesis. However, EFT participants were not better than controls at identifying whether they had been assigned to the experimental group and, likewise, showed no differences in attitudes about the experiment and experimenter. Importantly, effects of EFT on delay discounting and demand remained significant even when controlling for measures of demand characteristics, indicating that EFT's effects are independent of participants' perceptions about the experiment.
A Macroscopic Analogue of the Nuclear Pairing Potential
ERIC Educational Resources Information Center
Dunlap, Richard A.
2013-01-01
A macroscopic system involving permanent magnets is used as an analogue to nucleons in a nucleus to illustrate the significance of the pairing interaction. This illustrates that the view of the total nuclear energy based only on the nucleon occupancy of the energy levels can yield erroneous results and it is only when the pairing interaction is…
Global limits and interference patterns in dark matter direct detection
DOE Office of Scientific and Technical Information (OSTI.GOV)
Catena, Riccardo; Gondolo, Paolo
2015-08-13
We compare the general effective theory of one-body dark matter nucleon interactions to current direct detection experiments in a global multidimensional statistical analysis. We derive exclusion limits on the 28 isoscalar and isovector coupling constants of the theory, and show that current data place interesting constraints on dark matter-nucleon interaction operators usually neglected in this context. We characterize the interference patterns that can arise in dark matter direct detection from pairs of dark matter-nucleon interaction operators, or from isoscalar and isovector components of the same operator. We find that commonly neglected destructive interference effects weaken standard direct detection exclusion limitsmore » by up to one order of magnitude in the coupling constants.« less
Global limits and interference patterns in dark matter direct detection
DOE Office of Scientific and Technical Information (OSTI.GOV)
Catena, Riccardo; Gondolo, Paolo, E-mail: riccardo.catena@theorie.physik.uni-goettingen.de, E-mail: paolo.gondolo@utah.edu
2015-08-01
We compare the general effective theory of one-body dark matter nucleon interactions to current direct detection experiments in a global multidimensional statistical analysis. We derive exclusion limits on the 28 isoscalar and isovector coupling constants of the theory, and show that current data place interesting constraints on dark matter-nucleon interaction operators usually neglected in this context. We characterize the interference patterns that can arise in dark matter direct detection from pairs of dark matter-nucleon interaction operators, or from isoscalar and isovector components of the same operator. We find that commonly neglected destructive interference effects weaken standard direct detection exclusion limitsmore » by up to one order of magnitude in the coupling constants.« less
NASA Technical Reports Server (NTRS)
Dudkin, V. E.; Kovalev, E. E.; Nefedov, N. A.; Antonchik, V. A.; Bogdanov, S. D.; Kosmach, V. F.; Hassan, J.; Benton, E. V.; Crawford, H. J.
1994-01-01
Multiplicities of various species of charged secondaries produced in inelastic interactions of 20Ne, 40Ar and 56Fe nuclei with emulsion nuclei at 0.1-0.5 GeV/nucleon have been measured. The data obtained are compared with the results for interactions of higher energy nuclei with emulsion nuclei. The dependences of the nucleus-nucleus interaction parameters on masses and energies of colliding nuclei are examined.
Maxwell-Wagner relaxation in electrical imaging.
Korjenevsky, A V
2005-04-01
The electric field tomography (EFT) method exploits interaction of high-frequency electric field with an inhomogeneous conductive medium without contact with the electrodes. The interaction is accompanied by a high-frequency redistribution of free charges inside the medium and leads to small and regular phase shifts of the field in the area surrounding an object. Such a kind of phenomenon is referred to as the Maxwell-Wagner relaxation. Measuring the perturbations of the field using the set of electrodes placed around the object enables us to reconstruct the internal structure of the medium, generally the spatial distribution of a nonlinear combination of permittivity and resistivity. In the case of biomedical applications the result of measurements is determined mainly by the resistivity of the tissues. Three-dimensional simulation based on the finite element method has demonstrated the feasibility of the technique.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pelletier, C.
1960-01-01
The secondaries produced by the interaction of highenergy cosmic radiation with aluminum were studied with Wilson chambers placed in a magnetic field. From 9600 photographs made, 117 interactions of charged particles with energy higher than 10 Bev in aluminum were selected. These photographs were obtained with the apparatus installed at the Observatory of the Pic du Midi de Bigorre. This apparatus is described. The quantities of motion and the emission direction of charged secondaries of each interaction were determined. The measurements and the methods of calculation are described. The results obtained on charged secondaries and unstable particles are reported. Themore » selection of the interactions which occurred with only one nucleon of the aluminum nucleus is discussed. These interactions were studied in the center-of-mass system of the interacting particles. The results obtained are compared with the predictions of the principal theoreticat models of nucleon-nucleon interactions. (trauth)« less
The method of unitary clothing transformations in the theory of nucleon-nucleon scattering
NASA Astrophysics Data System (ADS)
Dubovyk, I.; Shebeko, A.
2010-04-01
The clothing procedure, put forward in quantum field theory (QFT) by Greenberg and Schweber, is applied for the description of nucleon-nucleon (N -N) scattering. We consider pseudoscalar (π and η), vector (ρ and ω) and scalar (δ and σ) meson fields interacting with 1/2 spin (N and N) fermion ones via the Yukawa-type couplings to introduce trial interactions between “bare” particles. The subsequent unitary clothing transformations (UCTs) are found to express the total Hamiltonian through new interaction operators that refer to particles with physical (observable) properties, the so-called clothed particles. In this work, we are focused upon the Hermitian and energy-independent operators for the clothed nucleons, being built up in the second order in the coupling constants. The corresponding analytic expressions in momentum space are compared with the separate meson contributions to the one-boson-exchange potentials in the meson theory of nuclear forces. In order to evaluate the T matrix of the N-N scattering we have used an equivalence theorem that enables us to operate in the clothed particle representation (CPR) instead of the bare particle representation (BPR) with its huge amount of virtual processes. We have derived the Lippmann-Schwinger(LS)-type equation for the CPR elements of the T-matrix for a given collision energy in the two-nucleon sector of the Hilbert space H of hadronic states and elaborated a code for its numerical solution in momentum space.
Binding energies and modelling of nuclei in semiclassical simulations
NASA Astrophysics Data System (ADS)
Pérez-García, M. Ángeles; Tsushima, K.; Valcarce, A.
2008-03-01
We study the binding energies of spin isospin saturated nuclei with nucleon number 8⩽A⩽100 in semiclassical Monte Carlo many-body simulations. The model Hamiltonian consists of (i) nucleon kinetic energy, (ii) a nucleon nucleon interaction potential, and (iii) an effective Pauli potential which depends on density. The basic ingredients of the nucleon nucleon potential are a short-range repulsion, and a medium-range attraction. Our results demonstrate that one can always expect to obtain the empirical binding energies for a set of nuclei by introducing a proper density dependent Pauli potential in terms of a single variable, the nucleon number, A. The present work shows that in the suggested procedure there is a delicate counterbalance of kinetic and potential energetic contributions allowing a good reproduction of the experimental nuclear binding energies. This type of calculations may be of interest in further reproduction of other properties of nuclei such as radii and also exotic nuclei.
A survey of the Australasian clinical medical physics and biomedical engineering workforce.
Round, W H
2007-03-01
A survey of the medical physics and biomedical engineering workforce was carried out in 2006. 495 positions (equivalent to 478 equivalent full time (EFT) positions) were captured by the survey. Of these 268 EFT were in radiation oncology physics, 36 EFT were in radiology physics, 44 were in nuclear medicine physics, 101 EFT were in biomedical engineering and 29 EFT were attributed to other activities. The survey reviewed the experience profile, the salary levels and the number of vacant positions in the workforce for the different disciplines in each Australian state and in New Zealand. Analysis of the data identifies staffing shortfalls in the various disciplines and demonstrates the difficulties that will occur in trying to train sufficient physicists to raise staffing to an acceptable level.
Church, Dawson; De Asis, Midanelle A.; Brooks, Audrey J.
2012-01-01
Two hundred thirty-eight first-year college students were assessed using the Beck Depression Inventory (BDI). Thirty students meeting the BDI criteria for moderate to severe depression were randomly assigned to either a treatment or control group. The treatment group received four 90-minute group sessions of EFT (Emotional Freedom Techniques), a novel treatment that combines exposure, cognitive reprocessing, and somatic stimulation. The control group received no treatment. Posttests were conducted 3 weeks later on those that completed all requirements (N = 18). The EFT group (n = 9) had significantly more depression at baseline than the control group (n = 9) (EFT BDI mean = 23.44, SD = 2.1 versus control BDI mean = 20.33, SD = 2.1). After controlling for baseline BDI score, the EFT group had significantly less depression than the control group at posttest, with a mean score in the “nondepressed” range (P = .001; EFT BDI mean = 6.08, SE = 1.8 versus control BDI mean = 18.04, SE = 1.8). Cohen's d was 2.28, indicating a very strong effect size. These results are consistent with those noted in other studies of EFT that included an assessment for depression and indicate the clinical usefulness of EFT as a brief, cost-effective, and efficacious treatment. PMID:22848802
Church, Dawson; De Asis, Midanelle A; Brooks, Audrey J
2012-01-01
Two hundred thirty-eight first-year college students were assessed using the Beck Depression Inventory (BDI). Thirty students meeting the BDI criteria for moderate to severe depression were randomly assigned to either a treatment or control group. The treatment group received four 90-minute group sessions of EFT (Emotional Freedom Techniques), a novel treatment that combines exposure, cognitive reprocessing, and somatic stimulation. The control group received no treatment. Posttests were conducted 3 weeks later on those that completed all requirements (N = 18). The EFT group (n = 9) had significantly more depression at baseline than the control group (n = 9) (EFT BDI mean = 23.44, SD = 2.1 versus control BDI mean = 20.33, SD = 2.1). After controlling for baseline BDI score, the EFT group had significantly less depression than the control group at posttest, with a mean score in the "nondepressed" range (P = .001; EFT BDI mean = 6.08, SE = 1.8 versus control BDI mean = 18.04, SE = 1.8). Cohen's d was 2.28, indicating a very strong effect size. These results are consistent with those noted in other studies of EFT that included an assessment for depression and indicate the clinical usefulness of EFT as a brief, cost-effective, and efficacious treatment.
High proton momenta and nucleon-nucleon correlations in the reaction /sup 3/He(e,e'p)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marchand, C.; Bernheim, M.; Dunn, P.C.
1988-04-25
Electron-scattering cross sections for the reaction /sup 3/He(e,e'p) have been measured for recoil momenta between 300 and 600 MeV/c and for missing energies up to 90 MeV. Proton momentum distributions in /sup 3/He, corrected for final-state--interaction and meson-exchange effects, have been obtained from 318 to 600 MeV/c for the pd channel and from 290 to 515 MeV/c for the ppn channel. Explicit evidence for nucleon-nucleon correlations is presented.
Neutrinoless Double Beta Decay Matrix Elements in Light Nuclei
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pastore, S.; Carlson, J.; Cirigliano, V.
We present the first ab initio calculations of neutrinoless double-β decay matrix elements in A=6-12 nuclei using variational Monte Carlo wave functions obtained from the Argonne v 18 two-nucleon potential and Illinois-7 three-nucleon interaction. We study both light Majorana neutrino exchange and potentials arising from a large class of multi-TeV mechanisms of lepton-number violation. Our results provide benchmarks to be used in testing many-body methods that can be extended to the heavy nuclei of experimental interest. In light nuclei we also study the impact of two-body short-range correlations and the use of different forms for the transition operators, such asmore » those corresponding to different orders in chiral effective theory.« less
Nucleon effective masses in neutron-rich matter
NASA Astrophysics Data System (ADS)
Li, Bao-An; Cai, Bao-Jun; Chen, Lie-Wen; Xu, Jun
2018-03-01
Various kinds of isovector nucleon effective masses are used in the literature to characterize the momentum/energy dependence of the nucleon symmetry potential or self-energy due to the space/time non-locality of the underlying isovector strong interaction in neutron-rich nucleonic matter. The multifaceted studies on nucleon isovector effective masses are multi-disciplinary in nature. Besides structures, masses and low-lying excited states of nuclei as well as nuclear reactions, studies of the isospin dependence of short-range correlations in nuclei from scatterings of high-energy electrons and protons on heavy nuclei also help understand nucleon effective masses especially the so-called E-mass in neutron-rich matter. A thorough understanding of all kinds of nucleon effective masses has multiple impacts on many interesting issues in both nuclear physics and astrophysics. Indeed, essentially all microscopic many-body theories and phenomenological models with various nuclear forces available in the literature have been used to calculate single-nucleon potentials and the associated nucleon effective masses in neutron-rich matter. There are also fundamental principles connecting different aspects and impacts of isovector strong interactions. In particular, the Hugenholtz-Van Hove theorem connects analytically nuclear symmetry energy with both isoscalar and isovector nucleon effective masses as well as their own momentum dependences. It also reveals how the isospin-quartic term in the equation of state of neutron-rich matter depends on the high-order momentum-derivatives of both isoscalar and isovector nucleon potentials. The Migdal-Luttinger theorem facilitates the extraction of nucleon E-mass and its isospin dependence from experimentally constrained single-nucleon momentum distributions. The momentum/energy dependence of the symmetry potential and the corresponding neutron-proton effective mass splitting also affect transport properties and the liquid-gas phase transition in neutron-rich matter. Moreover, they influence the dynamics and isospin-sensitive observables of heavy-ion collisions through both the Vlasov term and the collision integrals of the Boltzmann-Uehling-Uhlenbeck transport equation. We review here some of the significant progresses made in recent years by the nuclear physics community in resolving some of the hotly debated and longstanding issues regarding nucleon effective masses especially in dense neutron-rich matter. We also point out some of the remaining key issues requiring further investigations in the era of high precision experiments using advanced rare isotope beams.
The structure of the nucleon: Elastic electromagnetic form factors
Punjabi, V.; Perdrisat, C. F.; Jones, M. K.; ...
2015-07-10
Precise proton and neutron form factor measurements at Jefferson Lab, using spin observables, have recently made a significant contribution to the unraveling of the internal structure of the nucleon. Accurate experimental measurements of the nucleon form factors are a test-bed for understanding how the nucleon's static properties and dynamical behavior emerge from QCD, the theory of the strong interactions between quarks. There has been enormous theoretical progress, since the publication of the Jefferson Lab proton form factor ratio data, aiming at reevaluating the picture of the nucleon. We will review the experimental and theoretical developments in this field and discussmore » the outlook for the future.« less
Momentum transfer in the reactions of 13. 6-GeV/nucleon sup 16 O with copper
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cumming, J.B.; Chu, Y.Y.; Haustein, P.E.
1992-11-01
Mean ranges and forward-to-backward ratios have been determined by the thick-target, thick-catcher technique for fragments from the interaction of 13.6-GeV/nucleon {sup 16}O with copper. Experimental data are analyzed in terms of a two-step model and results are discussed in the context of limiting fragmentation and factorization and the predictions of a simple model for momentum transfer. Momenta imparted in the initial interactions of 13.6-GeV/nucleon {sup 16}O were inferred to be {similar to}12% lower than those for fragmentation of Cu by high-energy protons.
Nucleus-nucleus interactions between 20 and 65 GeV per nucleon
NASA Technical Reports Server (NTRS)
Burnett, T. H.; Derrickson, J. H.; Fountain, W. F.; Meegan, C. A.; Parnell, T. A.; Roberts, F. E.; Watts, J. W.; Oda, H.; Takahashi, Y.; Jones, W. V.
1987-01-01
A hybrid electronic-counter/emulsion-chamber instrument was exposed to high-energy cosmic rays on a balloon. The data on 105 nucleus-nucleus collisions in the energy range 20-65 GeV/nucleon and for incident nuclear charges Zp in the range of 22 to 28 are presented. Inclusive characteristics of particle production on different targets (plastic, emulsion, and lead) are shown and compared with models based on the superposition of nucleon-nucleus interactions. Features of a subset of the more central collisions with a plastic target and some characteristics of individual events with the highest multiplicity of produced particles are described.
Higgs mass prediction in the MSSM at three-loop level in a pure \\overline{{ {DR}}} context
NASA Astrophysics Data System (ADS)
Harlander, Robert V.; Klappert, Jonas; Voigt, Alexander
2017-12-01
The impact of the three-loop effects of order α _tα _s^2 on the mass of the light CP-even Higgs boson in the { {MSSM}} is studied in a pure \\overline{{ {DR}}} context. For this purpose, we implement the results of Kant et al. (JHEP 08:104, 2010) into the C++ module Himalaya and link it to FlexibleSUSY, a Mathematica and C++ package to create spectrum generators for BSM models. The three-loop result is compared to the fixed-order two-loop calculations of the original FlexibleSUSY and of FeynHiggs, as well as to the result based on an EFT approach. Aside from the expected reduction of the renormalization scale dependence with respect to the lower-order results, we find that the three-loop contributions significantly reduce the difference from the EFT prediction in the TeV-region of the { {SUSY}} scale {M_S}. Himalaya can be linked also to other two-loop \\overline{{ {DR}}} codes, thus allowing for the elevation of these codes to the three-loop level.
NASA Astrophysics Data System (ADS)
Parsaei, Sara; Rajabi, Ali Akbar
2018-01-01
The electromagnetic transition between the nucleon and excited baryons has long been recognized as an important source of information for understanding strong interactions in the domain of quark confinement. We study the electromagnetic properties of the excitation of the negative parity the N*(1535) resonances in the nonrelativistic constituent quark model at large momentum transfers and have performed a calculation the longitudinal and transverse helicity amplitudes. Since the helicity amplitudes depend strongly on the quark wave function in this paper, we consider the baryon as a simple, non-relativistically three-body quark model and also consider a hypercentral potential scheme for the internal baryon structure, which makes three-body forces among three quarks. Since the hyper central potential depends only on the hyper radius, therefore, the Cornell potential which is a combination of the Coulombic-like term plus a linear confining term is considered as the potential for interaction between quarks. In our work, in solving the Schrodinger equation with the Cornell potential, the Nikiforov-Uvarov method employed, and the analytic eigen-energies and eigen-functions obtained. By using the obtained eigen-functions, the transition amplitudes calculated. We show that our results in the range {{{Q}}}2> 2 {{GeV}}2 lead to an overall better agreement with the experimental data in comparison with the other three non-relativistic quark models.
Orion Core Stage & Booster Offload, Move to HIF
2014-03-04
CAPE CANAVERAL, Fla. – The core booster for the United Launch Alliance Delta IV heavy for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, was transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The core booster and starboard booster arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. The port booster and the upper stage are planned to be shipped to Cape Canaveral in April. At the HIF, all three boosters will be processed and checked out before being moved to the nearby launch pad and hoisted into position. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Wang, Dongxian; Luo, Benping; Shan, Weiran; Hao, Mingcong; Sun, Xuesong; Ge, Ruiguang
2013-06-01
Helicobacter pylori is a common human pathogen responsible for various gastric diseases. Bismuth can effectively inhibit the growth of this bacterium and is commonly recommended for the treatment of the related diseases. Translation elongation factors EF-Tu and EF-Ts are two important components of the protein translation system. EF-Ts has inhibitory effects on the GTPase activity of EF-Tu and enhances GDP release, a hint that careful timing for the introduction of EF-Ts in the elongation should be accomplished to prevent the complete inhibition of the elongation process. Bismuth inhibits the chaperone activity of EF-Tu, and has opposite effects on the elongation activity: inhibitory effects on the intrinsic GTPase activity and stimulation of GDP release. The present work deepens our understanding of the bacterial elongation process as mediated by EF-Tu and EF-Ts and extends our knowledge about the inhibitory effects of bismuth-based drugs against Helicobacter pylori.
Nucleon-nucleon scattering parameters in the limit of SU(3) flavor symmetry
NASA Astrophysics Data System (ADS)
Beane, S. R.; Chang, E.; Cohen, S. D.; Detmold, W.; Junnarkar, P.; Lin, H. W.; Luu, T. C.; Orginos, K.; Parreño, A.; Savage, M. J.; Walker-Loud, A.
2013-08-01
The scattering lengths and effective ranges that describe low-energy nucleon-nucleon scattering are calculated in the limit of SU(3)-flavor symmetry at the physical strange-quark mass with lattice quantum chromodynamics. The calculations are performed with an isotropic clover discretization of the quark action in three volumes with spatial extents of L˜3.4fm, 4.5fm, and 6.7fm, and with a lattice spacing of b˜0.145fm. With determinations of the energies of the two-nucleon systems (both of which contain bound states at these up and down quark masses) at rest and moving in the lattice volume, Lüscher's method is used to determine the low-energy phase shifts in each channel, from which the scattering length and effective range are obtained. The scattering parameters, in the 1S0 channel are found to be mπa(1S0)=9.50-0.69+0.78-0.80+1.10 and mπr(1S0)=4.61-0.31+0.29-0.26+0.24, and in the 3S1 channel are mπa(3S1)=7.45-0.53+0.57-0.49+0.71 and mπr(3S1)=3.71-0.31+0.28-0.35+0.28. These values are consistent with the two-nucleon system exhibiting Wigner's supermultiplet symmetry, which becomes exact in the limit of large Nc. In both spin channels, the phase shifts change sign at higher momentum, near the start of the t-channel cut, indicating that the nuclear interactions have a repulsive core even at the SU(3)-symmetric point.
Probing short-range nucleon-nucleon interactions with an electron-ion collider
Miller, Gerald A.; Sievert, Matthew D.; Venugopalan, Raju
2016-04-07
For this research, we derive the cross section for exclusive vector meson production in high-energy deeply inelastic scattering off a deuteron target that disintegrates into a proton and a neutron carrying large relative momentum in the final state. This cross section can be expressed in terms of a novel gluon transition generalized parton distribution (T-GPD); the hard scale in the final state makes the T-GPD sensitive to the short-distance nucleon-nucleon interaction. We perform a toy model computation of this process in a perturbative framework and discuss the time scales that allow the separation of initial- and final-state dynamics in themore » T-GPD. We outline the more general computation based on the factorization suggested by the toy computation: In particular, we discuss the relative role of “pointlike” and “geometric” Fock configurations that control the parton dynamics of short-range nucleon-nucleon scattering. With the aid of exclusive J/ψ production data at the Hadron-Electron Ring Accelerator at DESY, as well as elastic nucleon-nucleon cross sections, we estimate rates for exclusive deuteron photodisintegration at a future Electron-Ion Collider (EIC). Our results, obtained using conservative estimates of EIC integrated luminosities, suggest that center-of-mass energies sNN ~12GeV 2 of the neutron-proton subsystem can be accessed. We argue that the high energies of the EIC can address outstanding dynamical questions regarding the short-range quark-gluon structure of nuclear forces by providing clean gluon probes of such “knockout” exclusive reactions in light and heavy nuclei.« less
Episodic future thinking reduces eating in a food court.
O'Neill, Jessica; Daniel, Tinuke Oluyomi; Epstein, Leonard H
2016-01-01
Episodic future thinking (EFT) is the psychological process of vividly imagining a future event, and this process has been shown to reduce overeating in the laboratory. To assess the efficacy of EFT in the natural environment, twenty-nine overweight or obese women who wanted to improve their eating habits were randomly assigned to one of two smartphone-implemented interventions--EFT or control episodic recent thinking (ERT)--while they ate dinner in a public food court. Results showed a reduction in consumption of total calories, a reduction in percent calories from fat, and an increase in percent calories from protein for EFT versus ERT. These data suggest EFT may be used to modify eating habits in natural eating environments, and may show potential as a component of behavioral obesity interventions. Copyright © 2015 Elsevier Ltd. All rights reserved.
Proton-induced knockout reactions with polarized and unpolarized beams
NASA Astrophysics Data System (ADS)
Wakasa, T.; Ogata, K.; Noro, T.
2017-09-01
Proton-induced knockout reactions provide a direct means of studying the single particle or cluster structures of target nuclei. In addition, these knockout reactions are expected to play a unique role in investigations of the effects of the nuclear medium on nucleon-nucleon interactions as well as the properties of nucleons and mesons. However, due to the nature of hadron probes, these reactions can suffer significant disturbances from the nuclear surroundings and the quantitative theoretical treatment of such processes can also be challenging. In this article, we review the experimental and theoretical progress in this field, particularly focusing on the use of these reactions as a spectroscopic tool and as a way to examine the medium modification of nucleon-nucleon interactions. With regard to the former aspect, the review presents a semi-quantitative evaluation of these reactions based on existing experimental data. In terms of the latter point, we introduce a significant body of evidence that suggests, although does not conclusively prove, the existence of medium effects. In addition, this paper also provides information and comments on other related subjects.
Baryon mass splittings and strong CP violation in SU(3) chiral perturbation theory
de Vries, Jordy; Mereghetti, Emanuele; Walker-Loud, Andre P.
2015-10-08
We study SU(3) flavor breaking corrections to the relation between the octet baryon masses and the nucleon-meson CP-violating interactions induced by the QCD theta term. We also work within the framework of SU(3) chiral perturbation theory and work through next-to-next-to-leading order in the SU(3) chiral expansion, which is O(m 2 q). At lowest order, the CP-odd couplings induced by the QCD θ - term are determined by mass splittings of the baryon octet, the classic result of Crewther et al. We show that for each isospin-invariant CP-violating nucleon-meson interaction there exists one relation which is respected by loop corrections upmore » to the order we work, while other leading-order relations are violated. With these relations we extract a precise value of the pion-nucleon coupling g - 0 by using recent lattice QCD evaluations of the proton-neutron mass splitting. Additionally, we derive semi-precise values for CP-violating coupling constants between heavier mesons and nucleons and discuss their phenomenological impact on electric dipole moments of nucleons and nuclei.« less
Baryon mass splittings and strong CP violation in SU(3) chiral perturbation theory
DOE Office of Scientific and Technical Information (OSTI.GOV)
de Vries, Jordy; Mereghetti, Emanuele; Walker-Loud, Andre P.
We study SU(3) flavor breaking corrections to the relation between the octet baryon masses and the nucleon-meson CP-violating interactions induced by the QCD theta term. We also work within the framework of SU(3) chiral perturbation theory and work through next-to-next-to-leading order in the SU(3) chiral expansion, which is O(m 2 q). At lowest order, the CP-odd couplings induced by the QCD θ - term are determined by mass splittings of the baryon octet, the classic result of Crewther et al. We show that for each isospin-invariant CP-violating nucleon-meson interaction there exists one relation which is respected by loop corrections upmore » to the order we work, while other leading-order relations are violated. With these relations we extract a precise value of the pion-nucleon coupling g - 0 by using recent lattice QCD evaluations of the proton-neutron mass splitting. Additionally, we derive semi-precise values for CP-violating coupling constants between heavier mesons and nucleons and discuss their phenomenological impact on electric dipole moments of nucleons and nuclei.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Knyr, V. A.; Neudatchin, V. G.; Khokhlov, N. A.
Various pieces of evidence in favor of the Moscow potential of nucleon-nucleon interaction are discussed. The formalism of a relativistic potential model as applied to deuteron photodintegration is expounded. The differential cross section calculated for the reaction {gamma}d {sup {yields}} np on the basis of the Moscow potential at incident-photon energies E{sub {gamma}} between 1.5 and 2.5 GeV are quite in accord with present-day experimental data, which are also described well in the literature on the basis of the model of quark-gluon strings. Further steps in testing the Moscow potential and microscopically substantiating it on the basis of quark modelsmore » are indicated.« less
Interacting Boson Model and nucleons
NASA Astrophysics Data System (ADS)
Otsuka, Takaharu
2012-10-01
An overview on the recent development of the microscopic derivation of the Interacting Boson Model is presented with some remarks not found elsewhere. The OAI mapping is reviewed very briefly, including the basic correspondence from nucleon-pair to boson. The new fermionboson mapping method is introduced, where intrinsic states of nucleons and bosons for a wide variation of shapes play an important role. Nucleon intrinsic states are obtained from mean field models, which is Skyrme model in examples to be shown. This method generates IBM-2 Hamiltonian which can describe and predict various situations of quadrupole collective states, including U(5), SU(3), O(6) and E(5) limits. The method is extended so that rotational response (cranking) can be handled, which enables us to describe rotational bands of strongly deformed nuclei. Thus, we have obtained a unified framework for the microscopic derivation of the IBM covering all known situations of quadrupole collectivity at low energy.
Experimental Study of Three-Nucleon Dynamics in the Dp Breakup Collisions Using the WASA Detector
NASA Astrophysics Data System (ADS)
Kłos, B.; Ciepał, I.; Jamróz, B.; Khatri, G.; Kistryn, S.; Kozela, A.; Magiera, A.; Parol, W.; Skwira-Chalot, I.; Stephan, E.
2017-03-01
Until recently, all calculations of breakup observables were carried out in a non-relativistic regime. The relativistic treatment of the breakup reaction in 3 N system is quite a new achievement. The detailed study of various aspects of few-nucleon system dynamics in medium energy region, with a particular emphasis on investigation of relativistic effects and their interplay with three nucleon force (3NF) becomes feasible with increasing available energy in the three nucleon system. Therefore an experiment to investigate the ^1H(d, pp)n breakup cross section using a deuteron beam of 300, 340, 380 and 400 MeV and the WASA detector has been performed at COSY-Jülich. The almost 4π geometry of the WASA detector gives an unique possibility to study variety of kinematic configurations, which reveal different sensitivity to aspects of dynamics of the three nucleon system. The main steps of the analysis, including energy calibration, PID, normalization and efficiency studies, and their impact on the final accuracy of the result, are discussed.
Search for Dark Matter Interactions using Ionization Yield in Liquid Xenon
NASA Astrophysics Data System (ADS)
Uvarov, Sergey
Cosmological observations overwhelmingly support the existence of dark matter which constitutes 87% of the universe's total mass. Weakly Interacting Massive Particles (WIMPs) are a prime candidate for dark matter, and the Large Underground Xenon (LUX) experiment aims to a direct-detection of a WIMP-nucleon interaction. The LUX detector is a dual-phase xenon time-projection chamber housed 4,850 feet underground at Sanford Underground Research Facility in Lead, South Dakota. We present the ionization-only analysis of the LUX 2013 WIMP search data. In the 1.04 x 104 kg-days exposure, thirty events were observed out of the 24.8 expected from radioactive backgrounds. We employ a cut-and-count method to set a 1-sided 90% C.L. upper limit for spin-independent WIMP-nucleon cross-sections. A zero charge yield for nuclear-recoils below 0.7 keV is included upper limit calculation. This ionization-only analysis excludes an unexplored region of WIMP-nucleon cross-section for low-mass WIMPs achieving 1.56 x 10-43 cm2 WIMP-nucleon cross-section exclusion for a 5.1 GeV/ c2 WIMP.
A measurement of the neutral current neutrino-nucleon elastic cross section at MiniBooNE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cox, David Christopher
2008-02-01
The neutral current neutrino-nucleon elastic interaction v N → v N is a fundamental process of the weak interaction ideally suited for characterizing the structure of the nucleon neutral weak current. This process comprises ~18% of neutrino events in the neutrino oscillation experiment, MiniBooNE, ranking it as the experiment's third largest process. Using ~10% of MiniBooNE's available neutrino data, a sample of these events were identified and analyzed to determine the differential cross section as a function of the momentum transfer of the interaction, Q 2. This is the first measurement of a differential cross section with MiniBooNE data. Frommore » this analysis, a value for the nucleon axial mass M A was extracted to be 1.34 ± 0.25 GeV consistent with previous measurements. The integrated cross section for the Q 2 range 0.189 → 1.13 GeV 2 was calculated to be (8.8 ± 0.6(stat) ± 0.2(syst)) x 10 -40 cm 2.« less
NASA Astrophysics Data System (ADS)
Dzuba, V. A.; Flambaum, V. V.; Stadnik, Y. V.
2017-12-01
In the presence of P -violating interactions, the exchange of vector bosons between electrons and nucleons induces parity-nonconserving (PNC) effects in atoms and molecules, while the exchange of vector bosons between nucleons induces anapole moments of nuclei. We perform calculations of such vector-mediated PNC effects in Cs, Ba+ , Yb, Tl, Fr, and Ra+ using the same relativistic many-body approaches as in earlier calculations of standard-model PNC effects, but with the long-range operator of the weak interaction. We calculate nuclear anapole moments due to vector-boson exchange using a simple nuclear model. From measured and predicted (within the standard model) values for the PNC amplitudes in Cs, Yb, and Tl, as well as the nuclear anapole moment of 133Cs, we constrain the P -violating vector-pseudovector nucleon-electron and nucleon-proton interactions mediated by a generic vector boson of arbitrary mass. Our limits improve on existing bounds from other experiments by many orders of magnitude over a very large range of vector-boson masses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Jeong-Yeon; Hahn, Insik; Kim, Yeongduk
2009-06-15
The soft-rotator model is applied to self-consistent analyses of the nuclear level structures and the nucleon interaction data of the even-even Sn isotopes, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, and {sup 122}Sn. The model successfully describes low-lying collective levels of these isotopes, which exhibit neither typical rotational nor harmonic vibrational structures. The experimental nucleon interaction data--total neutron cross sections, proton reaction cross sections, and nucleon elastic and inelastic scattering data--are well described up to 200 MeV in a coupled-channels optical model approach. For the calculations, nuclear wave functions for the Sn isotopes are taken from the nonaxial soft-rotator model withmore » the model parameters adjusted to fit the measured low-lying collective level structures. We find that the {beta}{sub 2} and {beta}{sub 3} deformations for incident protons are larger than those for incident neutrons by {approx}15%, which is clear evidence of the deviation from the pure collective model for these isotopes.« less
The effective chiral Lagrangian from the theta term
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mereghetti, E., E-mail: emanuele@physics.arizona.ed; Hockings, W.H., E-mail: whockings@bmc.ed; Kolck, U. van, E-mail: vankolck@physics.arizona.ed
2010-11-15
We construct the effective chiral Lagrangian involving hadronic and electromagnetic interactions originating from the QCD {theta}-bar term. We impose vacuum alignment at both quark and hadronic levels, including field redefinitions to eliminate pion tadpoles. We show that leading time-reversal-violating (TV) hadronic interactions are related to isospin-violating interactions that can in principle be determined from charge-symmetry-breaking experiments. We discuss the complications that arise from TV electromagnetic interactions. Some implications of the expected sizes of various pion-nucleon TV interactions are presented, and the pion-nucleon form factor is used as an example.
Nuclear reactions from lattice QCD
Briceño, Raúl A.; Davoudi, Zohreh; Luu, Thomas C.
2015-01-13
In this study, one of the overarching goals of nuclear physics is to rigorously compute properties of hadronic systems directly from the fundamental theory of strong interactions, Quantum Chromodynamics (QCD). In particular, the hope is to perform reliable calculations of nuclear reactions which will impact our understanding of environments that occur during big bang nucleosynthesis, the evolution of stars and supernovae, and within nuclear reactors and high energy/density facilities. Such calculations, being truly ab initio, would include all two-nucleon and three- nucleon (and higher) interactions in a consistent manner. Currently, lattice QCD provides the only reliable option for performing calculationsmore » of some of the low-energy hadronic observables. With the aim of bridging the gap between lattice QCD and nuclear many-body physics, the Institute for Nuclear Theory held a workshop on Nuclear Reactions from Lattice QCD on March 2013. In this review article, we report on the topics discussed in this workshop and the path planned to move forward in the upcoming years.« less
Light fragments from (C + Be) interactions at 0.6 GeV/nucleon
Abramov, B. M.; Alekseev, P. N.; Borodin, Yu. A.; ...
2016-05-01
We measured nuclear fragments emitted at 3.5° in 12C fragmentation at 0.6 GeV/nucleon. We also used the spectra obtained to test the predictions of four ion-ion interaction models: INCL++, BC, LAQGSM03.03 and QMD as well as for the comparison with the analytical parametrization in the framework of thermodynamical picture of fragmentation.
Statistical uncertainties of a chiral interaction at next-to-next-to leading order
Ekström, A.; Carlsson, B. D.; Wendt, K. A.; ...
2015-02-05
In this paper, we have quantified the statistical uncertainties of the low-energy coupling-constants (LECs) of an optimized nucleon–nucleon interaction from chiral effective field theory at next-to-next-to-leading order. Finally, in addition, we have propagated the impact of the uncertainties of the LECs to two-nucleon scattering phase shifts, effective range parameters, and deuteron observables.
Light-Nuclei Spectra from Chiral Dynamics
NASA Astrophysics Data System (ADS)
Piarulli, M.; Baroni, A.; Girlanda, L.; Kievsky, A.; Lovato, A.; Lusk, Ewing; Marcucci, L. E.; Pieper, Steven C.; Schiavilla, R.; Viviani, M.; Wiringa, R. B.
2018-02-01
In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods in order to test to what extent the chiral effective field theory framework impacts our knowledge of few- and many-body systems. In this Letter, we present Green's function Monte Carlo calculations of light nuclei based on the family of local two-body interactions presented by our group in a previous paper in conjunction with chiral three-body interactions fitted to bound- and scattering-state observables in the three-nucleon sector. These interactions include Δ intermediate states in their two-pion-exchange components. We obtain predictions for the energy levels and level ordering of nuclei in the mass range A =4 - 12 , accurate to ≤2 % of the binding energy, in very satisfactory agreement with experimental data.
Medium-heavy nuclei from nucleon-nucleon interactions in lattice QCD
NASA Astrophysics Data System (ADS)
Inoue, Takashi; Aoki, Sinya; Charron, Bruno; Doi, Takumi; Hatsuda, Tetsuo; Ikeda, Yoichi; Ishii, Noriyoshi; Murano, Keiko; Nemura, Hidekatsu; Sasaki, Kenji; HAL QCD Collaboration
2015-01-01
On the basis of the Brueckner-Hartree-Fock method with the nucleon-nucleon forces obtained from lattice QCD simulations, the properties of the medium-heavy doubly magic nuclei such as 16O and 40Ca are investigated. We found that those nuclei are bound for the pseudoscalar meson mass MPS≃470 MeV. The mass number dependence of the binding energies, single-particle spectra, and density distributions are qualitatively consistent with those expected from empirical data at the physical point, although these hypothetical nuclei at heavy quark mass have smaller binding energies than the real nuclei.
Search for three-nucleon short-range correlations in light nuclei
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Z.; Solvignon, P.; Nguyen, D.
Here, we present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive 4He/ 3He cross section ratio is observed to be both x and Q 2 independent for 1.5 < x < 2, confirming the dominance of two- nucleon (2N) short-range correlations (SRCs). For x > 2, our data do not support a previous claim of three-nucleon (3N) correlation dominance. While contributions beyond those from stationary 2N- SRCs are observed, our data show that isolating 3N-SRCs is more complicated than for 2N-SRCs.
Search for three-nucleon short-range correlations in light nuclei
Ye, Z.; Solvignon, P.; Nguyen, D.; ...
2018-06-18
Here, we present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive 4He/ 3He cross section ratio is observed to be both x and Q 2 independent for 1.5 < x < 2, confirming the dominance of two- nucleon (2N) short-range correlations (SRCs). For x > 2, our data do not support a previous claim of three-nucleon (3N) correlation dominance. While contributions beyond those from stationary 2N- SRCs are observed, our data show that isolating 3N-SRCs is more complicated than for 2N-SRCs.
Faghihi, Shadi; Vasheghani-Farahani, Ali; Parsaee, Mozhgan; Saedi, Sedigheh; Ghadrdoost, Behshid
2015-01-01
Background: The association between epicardial fat thickness (EFT) and premature coronary artery disease (CAD) has not been elaborately studied. Objectives: In the present study, we sought whether such a relationship between EFT and CAD exists. Patients and Methods: Sixty two consecutive subjects, under 50 years of age, who underwent coronary angiography (CAG) with the aspect of CAD, were included in this case control study. They were divided into two groups of 31 subjects, namely CAD (cases) and non-CAD (controls) group, according to CAG data. Presence of conventional coronary risk factors, drug history, and anthropometric data were recorded. Then, each subject underwent standard transthoracic echocardiography for measuring EFT in the proximal part of right ventricular outflow tract in the parasternal long axis view at end diastole, as well as other parameters of systolic and diastolic function, and left ventricle (LV) mass. Images were stored for offline analysis when the echocardiocardiographers were blind to CAG data. Results: Among baseline characteristics, waist circumference, triglyceride levels, cigarette smoking and history of statin use were significantly higher in the CAD group. The body mass index (BMI) was significantly higher in the non-CAD group. According to echocardiographic data, the EFT with a cut off value of 2.95 mm could well differentiate subjects in each group. The LV mass and E/e were significantly higher in CAD group, in addition to EFT. Also, there was a significant correlation between EFT and waist circumference, as well as LV mass. However, no significant relation was between EFT and LV systolic and diastolic function. Conclusions: The EFT, as measured by echocardiography, with a cut off value 2.95 mm has a strong association with premature CAD. PMID:26380819
Study of p-4He total reaction cross-section using Glauber and Coulomb-modified Glauber models
NASA Astrophysics Data System (ADS)
Tag El-Din, Ibrahim M. A.; Taha, M. M.; Hassan, Samia S. A.
2014-02-01
The total nuclear reaction cross-section σR for p-4He in the energy range from 25 MeV to 1000 MeV is calculated within Glauber and Coulomb-modified Glauber models. The Coulomb-modified Glauber model (CMGM) is introduced via modification of the Coulomb trajectory of the projectile from a straight line, and calculation of the effective radius of interaction. The effects of in-medium nucleon-nucleon (NN) total cross-section, phase variation, high order momentum transfer component of nucleon-nucleon elastic scattering amplitude and Pauli blocking are studied. It is pointed out that the phase variation of the nucleon-nucleon amplitude plays a significant role in describing σR with γ = -1.6 fm2 at in-medium nuclear density ϱ = 0 and γ = -2 fm2 at ϱ = 0.17 fm-3 in the whole energy range. A remarkable fit to the available experimental data is obtained by invoking Pauli blocking and high order momentum transfer of nucleon-nucleon (NN) elastic scattering amplitude for Ep < 100 MeV.
NASA Astrophysics Data System (ADS)
Melendez, Jordan; Wesolowski, Sarah; Furnstahl, Dick
2017-09-01
Chiral effective field theory (EFT) predictions are necessarily truncated at some order in the EFT expansion, which induces an error that must be quantified for robust statistical comparisons to experiment. A Bayesian model yields posterior probability distribution functions for these errors based on expectations of naturalness encoded in Bayesian priors and the observed order-by-order convergence pattern of the EFT. As a general example of a statistical approach to truncation errors, the model was applied to chiral EFT for neutron-proton scattering using various semi-local potentials of Epelbaum, Krebs, and Meißner (EKM). Here we discuss how our model can learn correlation information from the data and how to perform Bayesian model checking to validate that the EFT is working as advertised. Supported in part by NSF PHY-1614460 and DOE NUCLEI SciDAC DE-SC0008533.
Two-Nucleon Momentum Distributions Measured in 3He(e,e'pp)n
NASA Astrophysics Data System (ADS)
Niyazov, R. A.; Weinstein, L. B.; Adams, G.; Ambrozewicz, P.; Anciant, E.; Anghinolfi, M.; Asavapibhop, B.; Asryan, G.; Audit, G.; Auger, T.; Avakian, H.; Bagdasaryan, H.; Ball, J. P.; Barrow, S.; Battaglieri, M.; Beard, K.; Bektasoglu, M.; Bellis, M.; Benmouna, N.; Berman, B. L.; Bertozzi, W.; Bianchi, N.; Biselli, A. S.; Boiarinov, S.; Bonner, B. E.; Bouchigny, S.; Bradford, R.; Branford, D.; Brooks, W. K.; Burkert, V. D.; Butuceanu, C.; Calarco, J. R.; Carman, D. S.; Carnahan, B.; Cetina, C.; Chen, S.; Ciciani, L.; Cole, P. L.; Coleman, A.; Cords, D.; Corvisiero, P.; Crabb, D.; Crannell, H.; Cummings, J. P.; de Sanctis, E.; Dashyan, N.; Devita, R.; Degtyarenko, P. V.; Denizli, H.; Dennis, L.; Dharmawardane, K. V.; Dhuga, K. S.; Djalali, C.; Dodge, G. E.; Doughty, D.; Dragovitsch, P.; Dugger, M.; Dytman, S.; Dzyubak, O. P.; Eckhause, M.; Egiyan, H.; Egiyan, K. S.; Elouadrhiri, L.; Empl, A.; Eugenio, P.; Fatemi, R.; Feuerbach, R. J.; Ficenec, J.; Forest, T. A.; Funsten, H.; Gavalian, G.; Gilad, S.; Gilfoyle, G. P.; Giovanetti, K. L.; Girard, P.; Gordon, C. I.; Gothe, R. W.; Griffioen, K.; Guidal, M.; Guillo, M.; Guo, L.; Gyurjyan, V.; Hadjidakis, C.; Hakobyan, R. S.; Hardie, J.; Heddle, D.; Hersman, F. W.; Hicks, K.; Holtrop, M.; Hu, J.; Hyde-Wright, C. E.; Ilieva, Y.; Ingram, W.; Ito, M. M.; Jenkins, D.; Joo, K.; Juengst, H. G.; Kelley, J. H.; Kellie, J.; Khandaker, M.; Kim, D. H.; Kim, K. Y.; Kim, K.; Kim, M. S.; Kim, W.; Klein, A.; Klein, F. J.; Klimenko, A. V.; Klusman, M.; Kossov, M.; Kramer, L. H.; Kuang, Y.; Kuhn, S. E.; Kuhn, J.; Lachniet, J.; Laget, J. M.; Langheinrich, J.; Lawrence, D.; Li, Ji; Livingston, K.; Lukashin, K.; Manak, J. J.; Marchand, C.; McAleer, S.; McLauchlan, S.; McNabb, J. W.; Mecking, B. A.; Mehrabyan, S.; Melone, J. J.; Mestayer, M. D.; Meyer, C. A.; Mikhailov, K.; Mirazita, M.; Miskimen, R.; Morand, L.; Morrow, S. A.; Muccifora, V.; Mueller, J.; Mutchler, G. S.; Napolitano, J.; Nasseripour, R.; Nelson, S. O.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Niczyporuk, B. B.; Nozar, M.; O'Rielly, G. V.; Osipenko, M.; Park, K.; Pasyuk, E.; Peterson, G.; Philips, S. A.; Pivnyuk, N.; Pocanic, D.; Pogorelko, O.; Polli, E.; Pozdniakov, S.; Preedom, B. M.; Price, J. W.; Prok, Y.; Protopopescu, D.; Qin, L. M.; Raue, B. A.; Riccardi, G.; Ricco, G.; Ripani, M.; Ritchie, B. G.; Ronchetti, F.; Rossi, P.; Rowntree, D.; Rubin, P. D.; Sabatié, F.; Sabourov, K.; Salgado, C.; Santoro, J. P.; Sapunenko, V.; Schumacher, R. A.; Serov, V. S.; Shafi, A.; Sharabian, Y. G.; Shaw, J.; Simionatto, S.; Skabelin, A. V.; Smith, E. S.; Smith, L. C.; Sober, D. I.; Spraker, M.; Stavinsky, A.; Stepanyan, S.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Taylor, S.; Tedeschi, D. J.; Thoma, U.; Thompson, R.; Todor, L.; Tur, C.; Ungaro, M.; Vineyard, M. F.; Vlassov, A. V.; Wang, K.; Weller, H.; Weygand, D. P.; Whisnant, C. S.; Wolin, E.; Wood, M. H.; Yegneswaran, A.; Yun, J.; Zhang, B.
2004-02-01
We have measured the 3He(e,e'pp)n reaction at 2.2GeV over a wide kinematic range. The kinetic energy distribution for “fast” nucleons (p>250 MeV/c) peaks where two nucleons each have 20% or less, and the third nucleon has most of the transferred energy. These fast pp and pn pairs are back to back with little momentum along the three-momentum transfer, indicating that they are spectators. Calculations by Sargsian and by Laget also indicate that we have measured distorted two-nucleon momentum distributions by striking one nucleon and detecting the spectator correlated pair.
Emergent properties of nuclei from ab initio coupled-cluster calculations
NASA Astrophysics Data System (ADS)
Hagen, G.; Hjorth-Jensen, M.; Jansen, G. R.; Papenbrock, T.
2016-06-01
Emergent properties such as nuclear saturation and deformation, and the effects on shell structure due to the proximity of the scattering continuum and particle decay channels are fascinating phenomena in atomic nuclei. In recent years, ab initio approaches to nuclei have taken the first steps towards tackling the computational challenge of describing these phenomena from Hamiltonians with microscopic degrees of freedom. This endeavor is now possible due to ideas from effective field theories, novel optimization strategies for nuclear interactions, ab initio methods exhibiting a soft scaling with mass number, and ever-increasing computational power. This paper reviews some of the recent accomplishments. We also present new results. The recently optimized chiral interaction NNLO{}{{sat}} is shown to provide an accurate description of both charge radii and binding energies in selected light- and medium-mass nuclei up to 56Ni. We derive an efficient scheme for including continuum effects in coupled-cluster computations of nuclei based on chiral nucleon-nucleon and three-nucleon forces, and present new results for unbound states in the neutron-rich isotopes of oxygen and calcium. The coupling to the continuum impacts the energies of the {J}π =1/{2}-,3/{2}-,7/{2}-,3/{2}+ states in {}{17,23,25}O, and—contrary to naive shell-model expectations—the level ordering of the {J}π =3/{2}+,5/{2}+,9/{2}+ states in {}{53,55,61}Ca. ).
Effects of the U boson on the inner edge of neutron star crusts
NASA Astrophysics Data System (ADS)
Zheng, Hao; Chen, Lie-Wen
2012-02-01
We explore effects of the light vector U boson, which is weakly coupled to nucleons, on the transition density ρt and pressure Pt at the inner edge separating the liquid core from the solid crust of neutron stars. Three methods, i.e., the thermodynamical approach, the curvature matrix approach, and the Vlasov equation approach, are used to determine the transition density ρt with the Skyrme effective nucleon-nucleon interactions. We find that the ρt and Pt depend on not only the ratio of coupling strength to mass squared of the U boson g2/μ2 but also its mass μ due to the finite-range interaction from the U-boson exchange. In particular, our results indicate that the ρt and Pt are sensitive to both g2/μ2 and μ if the U-boson mass μ is larger than about 2 MeV. Furthermore, we show that both g2/μ2 and μ can have significant influence on the mass-radius relation and the crustal fraction of total moment of inertia of neutron stars. In addition, we study the exchange term contribution of the U boson based on the density matrix expansion method, and demonstrate that the exchange term effects on the nuclear matter equation of state as well as the ρt and Pt are generally negligible.
Principal shapes and squeezed limits in the effective field theory of large scale structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bertolini, Daniele; Solon, Mikhail P., E-mail: dbertolini@lbl.gov, E-mail: mpsolon@lbl.gov
2016-11-01
We apply an orthogonalization procedure on the effective field theory of large scale structure (EFT of LSS) shapes, relevant for the angle-averaged bispectrum and non-Gaussian covariance of the matter power spectrum at one loop. Assuming natural-sized EFT parameters, this identifies a linear combination of EFT shapes—referred to as the principal shape—that gives the dominant contribution for the whole kinematic plane, with subdominant combinations suppressed by a few orders of magnitude. For the covariance, our orthogonal transformation is in excellent agreement with a principal component analysis applied to available data. Additionally we find that, for both observables, the coefficients of themore » principal shapes are well approximated by the EFT coefficients appearing in the squeezed limit, and are thus measurable from power spectrum response functions. Employing data from N-body simulations for the growth-only response, we measure the single EFT coefficient describing the angle-averaged bispectrum with Ο (10%) precision. These methods of shape orthogonalization and measurement of coefficients from response functions are valuable tools for developing the EFT of LSS framework, and can be applied to more general observables.« less
Medication administration via enteral feeding tube: a survey of pharmacists' knowledge.
Joos, Elke; Verbeke, Stacey; Mehuys, Els; Van Bocxlaer, Jan; Remon, Jean Paul; Van Winckel, Myriam; Boussery, Koen
2016-02-01
Medication administration to patients with an enteral feeding tube (EFT) is complex and prone to errors. Community pharmacists may be ideally placed to provide training and advice on this topic in individual patients as well as in institutions supplied by the pharmacy. To assess community pharmacists’ knowledge on guideline recommendations regarding medication preparation and administration through EFT. Knowledge of guideline recommendations was assessed using a 15-item self-administered online questionnaire (April–June 2014). Questions reflected key aspects of guideline recommendations on medication administration via EFT. All graduated community pharmacists from the Dutch-speaking part of Belgium were eligible for participation. A total of 105 community pharmacists completed the questionnaire. Median self-perceived knowledge of medication administration via EFT was 2 (on a 0–10 scale). On average 5.2 (SD 2.6) out of the 15 questions were answered correctly. Strikingly, the ability to select suspensions in a list of liquid medications and knowledge on crushability of solid dosage forms were low. Our findings demonstrate that pharmacists’ knowledge on correct medication administration via EFT is too limited to be able to provide good advice to EFT patients or their caregivers. Tailored training on this topic is needed.
Thermal states of neutron stars with a consistent model of interior
NASA Astrophysics Data System (ADS)
Fortin, M.; Taranto, G.; Burgio, G. F.; Haensel, P.; Schulze, H.-J.; Zdunik, J. L.
2018-04-01
We model the thermal states of both isolated neutron stars and accreting neutron stars in X-ray transients in quiescence and confront them with observations. We use an equation of state calculated using realistic two-body and three-body nucleon interactions, and superfluid nucleon gaps obtained using the same microscopic approach in the BCS approximation. Consistency with low-luminosity accreting neutron stars is obtained, as the direct Urca process is operating in neutron stars with mass larger than 1.1 M⊙ for the employed equation of state. In addition, proton superfluidity and sufficiently weak neutron superfluidity, obtained using a scaling factor for the gaps, are necessary to explain the cooling of middle-aged neutron stars and to obtain a realistic distribution of neutron star masses.
Exclusive Meson Electroweak production off Bound Nucleons
NASA Astrophysics Data System (ADS)
Sato, Toru
2018-05-01
The effects of final state interaction in electroweak pion production reactions have been studied. The one loop corrections to the impulse approximation due to the nucleon and the pion rescattering is evaluated using the ANL-Osaka dynamical coupled channel model for the meson production reactions. It is found the final state interaction will affects the ν N cross section extracted in the previous analysis of the ν d data.
Massive neutron star with strangeness in a relativistic mean-field model with a high-density cutoff
NASA Astrophysics Data System (ADS)
Zhang, Ying; Hu, Jinniu; Liu, Peng
2018-01-01
The properties of neutron stars with the strangeness degree of freedom are studied in the relativistic mean-field (RMF) model via including a logarithmic interaction as a function of the scalar meson field. This interaction, named the σ -cut potential, can largely reduce the attractive contributions of the scalar meson field at high density without any influence on the properties of nuclear structure around the normal saturation density. In this work, the TM1 parameter set is chosen as the RMF interaction, while the strengths of σ -cut potential are constrained by the properties of finite nuclei so that we can obtain a reasonable effective nucleon-nucleon interaction. The hyperons Λ ,Σ , and Ξ are considered in neutron stars within this framework, whose coupling constants with mesons are determined by the latest hyperon-nucleon and Λ -Λ potentials extracted from the available experimental data of hypernuclei. The maximum mass of neutron star can be larger than 2 M⊙ with these hyperons in the present framework. Furthermore, the nucleon mass at high density will be saturated due to this additional σ -cut potential, which is consistent with the conclusions obtained by other calculations such as Brueckner-Hartree-Fock theory and quark mean-field model.
Three-particle N π π state contribution to the nucleon two-point function in lattice QCD
NASA Astrophysics Data System (ADS)
Bär, Oliver
2018-05-01
The three-particle N π π state contribution to the QCD two-point function of standard nucleon interpolating fields is computed to leading order in chiral perturbation theory. Using the experimental values for two low-energy coefficients, the impact of this contribution on lattice QCD calculations of the nucleon mass is estimated. The impact is found to be at the per mille level at most and negligible in practice.
Effect of repulsive and attractive three-body forces on nucleus-nucleus elastic scattering
DOE Office of Scientific and Technical Information (OSTI.GOV)
Furumoto, T.; Sakuragi, Y.; Yamamoto, Y.
2009-10-15
The effect of the three-body force (TBF) is studied in nucleus-nucleus elastic scattering on the basis of Brueckner theory for nucleon-nucleon (NN) effective interaction (complex G matrix) in the nuclear matter. A new G matrix called CEG07 proposed recently by the present authors includes the TBF effect and reproduces a realistic saturation curve in the nuclear matter, and it is shown to well reproduce proton-nucleus elastic scattering. The microscopic optical potential for the nucleus-nucleus system is obtained by folding the G matrix with nucleon density distributions in colliding nuclei. We first analyze in detail the {sup 16}O+{sup 16}O elastic scatteringmore » at E/A=70 MeV. The observed cross sections are nicely reproduced up to the most backward scattering angles only when the TBF effect is included. The use of the frozen-density approximation (FDA) is essentially important to properly estimate the effect of the TBF in nucleus-nucleus scattering. Other prescriptions for defining the local density have also been tested, but only the FDA prescription gives a proper description of the experimental cross sections as well as the effect of the TBF. The effects of the three-body attraction and the {omega}-rearrangement term are also analyzed. The CEG07 interaction is compared with CDM3Y6, which is a reliable and successful effective density-dependent NN interaction used in the double-folding model. The CEG07 G matrix is also tested in the elastic scattering of {sup 16}O by the {sup 12}C, {sup 28}Si, and {sup 40}Ca targets at E/A=93.9 MeV, and in the elastic scattering of {sup 12}C by the {sup 12}C target at E/A=135 MeV with great success. The decisive effect of the TBF is clearly seen also in those systems. Finally, we have tested CEG07a, CEG07b, and CEG07c for the {sup 16}O+{sup 16}O system at various energies.« less
Dependence of two-proton radioactivity on nuclear pairing models
NASA Astrophysics Data System (ADS)
Oishi, Tomohiro; Kortelainen, Markus; Pastore, Alessandro
2017-10-01
Sensitivity of two-proton emitting decay to nuclear pairing correlation is discussed within a time-dependent three-body model. We focus on the 6Be nucleus assuming α +p +p configuration, and its decay process is described as a time evolution of the three-body resonance state. For a proton-proton subsystem, a schematic density-dependent contact (SDDC) pairing model is employed. From the time-dependent calculation, we observed the exponential decay rule of a two-proton emission. It is shown that the density dependence does not play a major role in determining the decay width, which can be controlled only by the asymptotic strength of the pairing interaction. This asymptotic pairing sensitivity can be understood in terms of the dynamics of the wave function driven by the three-body Hamiltonian, by monitoring the time-dependent density distribution. With this simple SDDC pairing model, there remains an impossible trinity problem: it cannot simultaneously reproduce the empirical Q value, decay width, and the nucleon-nucleon scattering length. This problem suggests that a further sophistication of the theoretical pairing model is necessary, utilizing the two-proton radioactivity data as the reference quantities.
Experimental study of relativistic effects in the dp breakup reaction using the WASA detector
NASA Astrophysics Data System (ADS)
Kłos, B.; Ciepał, I.; Jamróz, B.; Khatri, G.; Kistryn, S.; Kozela, A.; Magiera, A.; Parol, W.; Skwira-Chalot, I.; Stephan, E.
2014-03-01
An experiment to investigate the 1H(overrightarrow d , pp)n breakup reaction at 340 MeV, 360 MeV and 400 MeV deuteron beam energy has been performed at the Cooler Synchrotron COSY-Jülich with the WASA detector. The main goal was to study of various aspects of few-nucleon dynamics in the medium energy region, with a particular emphasis on relativistic effects and their interplay with three nucelon forces. The almost 4π geometry of the WASA detector gives an unique possibility to study the different aspects of nucleon-nucleon dynamics in the three nucleon system. The preliminary analysis of the collected data is presented.
Low-energy antikaon nucleon and nucleus interaction studies
NASA Astrophysics Data System (ADS)
Marton, Johann; Leannis Collaboration
2011-04-01
The antikaon (K-) interaction on nucleons and nuclei at low energy is neither simple nor well understood. Kaonic hydrogen is a very interesting case where the strong interaction of K- with the proton leads to an energy shift and a broadening of the 1s ground state. These two observables can be precisely studied with x-ray spectroscopy. The behavior at threshold is influenced strongly by the elusive Lambda(1405) resonance. In Europe the DAFNE electron-positron collider at Laboratori Nazionali di Frascati (LNF) provides an unique source of monoenergetic kaons emitted in the Phi meson decay. Recently the experiment SIDDHARTA on kaonic hydrogen and helium isotopes was successfully performed at LNF. A European network LEANNIS with an outreach to J-PARC in Japan was set up which is promoting the research on the antikaon interactions with nucleons and nuclei. This talk will give an overview of LEANNIS research tasks, the present status and an outlook to future perspectives. Financial support by the EU project HadronPhysics2 is gratefully acknowledged.
New physics with ultra-high-energy neutrinos
Marfatia, D.; McKay, D. W.; Weiler, T. J.
2015-07-03
Now that PeV neutrinos have been discovered by IceCube, we optimistically entertain the possibility that neutrinos with energy above 100PeV exist. Here, we evaluate the dependence of event rates of such neutrinos on the neutrino-nucleon cross section at observatories that detect particles, atmospheric fluorescence, or Cherenkov radiation, initiated by neutrino interactions. We consider how (i)a simple scaling of the total standard model neutrino-nucleon cross section, (ii) a new elastic neutral current interaction, and (iii) anew completely inelastic interaction, individually impact event rates.
Probing Sub-GeV Mass Strongly Interacting Dark Matter with a Low-Threshold Surface Experiment.
Davis, Jonathan H
2017-11-24
Using data from the ν-cleus detector, based on the surface of Earth, we place constraints on dark matter in the form of strongly interacting massive particles (SIMPs) which interact with nucleons via nuclear-scale cross sections. For large SIMP-nucleon cross sections, the sensitivity of traditional direct dark matter searches using underground experiments is limited by the energy loss experienced by SIMPs, due to scattering with the rock overburden and experimental shielding on their way to the detector apparatus. Hence, a surface-based experiment is ideal for a SIMP search, despite the much larger background resulting from the lack of shielding. We show using data from a recent surface run of a low-threshold cryogenic detector that values of the SIMP-nucleon cross section up to approximately 10^{-27} cm^{2} can be excluded for SIMPs with masses above 100 MeV.
Quantified Gamow shell model interaction for p s d -shell nuclei
NASA Astrophysics Data System (ADS)
Jaganathen, Y.; Betan, R. M. Id; Michel, N.; Nazarewicz, W.; Płoszajczak, M.
2017-11-01
Background: The structure of weakly bound and unbound nuclei close to particle drip lines is one of the major science drivers of nuclear physics. A comprehensive understanding of these systems goes beyond the traditional configuration interaction approach formulated in the Hilbert space of localized states (nuclear shell model) and requires an open quantum system description. The complex-energy Gamow shell model (GSM) provides such a framework as it is capable of describing resonant and nonresonant many-body states on equal footing. Purpose: To make reliable predictions, quality input is needed that allows for the full uncertainty quantification of theoretical results. In this study, we carry out the optimization of an effective GSM (one-body and two-body) interaction in the p s d f -shell-model space. The resulting interaction is expected to describe nuclei with 5 ≤A ≲12 at the p -s d -shell interface. Method: The one-body potential of the 4He core is modeled by a Woods-Saxon + spin-orbit + Coulomb potential, and the finite-range nucleon-nucleon interaction between the valence nucleons consists of central, spin-orbit, tensor, and Coulomb terms. The GSM is used to compute key fit observables. The χ2 optimization is performed using the Gauss-Newton algorithm augmented by the singular value decomposition technique. The resulting covariance matrix enables quantification of statistical errors within the linear regression approach. Results: The optimized one-body potential reproduces nucleon-4He scattering phase shifts up to an excitation energy of 20 MeV. The two-body interaction built on top of the optimized one-body field is adjusted to the bound and unbound ground-state binding energies and selected excited states of the helium, lithium, and beryllium isotopes up to A =9 . A very good agreement with experimental results was obtained for binding energies. First applications of the optimized interaction include predictions for two-nucleon correlation densities and excitation spectra of light nuclei with quantified uncertainties. Conclusion: The new interaction will enable comprehensive and fully quantified studies of structure and reactions aspects of nuclei from the p s d region of the nuclear chart.
Quantified Gamow shell model interaction for p s d -shell nuclei
Jaganathen, Y.; Betan, R. M. Id; Michel, N.; ...
2017-11-20
Background: The structure of weakly bound and unbound nuclei close to particle drip lines is one of the major science drivers of nuclear physics. A comprehensive understanding of these systems goes beyond the traditional configuration interaction approach formulated in the Hilbert space of localized states (nuclear shell model) and requires an open quantum system description. The complex-energy Gamow shell model (GSM) provides such a framework as it is capable of describing resonant and nonresonant many-body states on equal footing. Purpose: To make reliable predictions, quality input is needed that allows for the full uncertainty quantification of theoretical results. In thismore » study, we carry out the optimization of an effective GSM (one-body and two-body) interaction in the psdf-shell-model space. The resulting interaction is expected to describe nuclei with 5 ≤ A ≲ 12 at the p-sd-shell interface. Method: The one-body potential of the 4He core is modeled by a Woods-Saxon + spin-orbit + Coulomb potential, and the finite-range nucleon-nucleon interaction between the valence nucleons consists of central, spin-orbit, tensor, and Coulomb terms. The GSM is used to compute key fit observables. The χ 2 optimization is performed using the Gauss-Newton algorithm augmented by the singular value decomposition technique. The resulting covariance matrix enables quantification of statistical errors within the linear regression approach. Results: The optimized one-body potential reproduces nucleon- 4He scattering phase shifts up to an excitation energy of 20 MeV. The two-body interaction built on top of the optimized one-body field is adjusted to the bound and unbound ground-state binding energies and selected excited states of the helium, lithium, and beryllium isotopes up to A = 9 . A very good agreement with experimental results was obtained for binding energies. First applications of the optimized interaction include predictions for two-nucleon correlation densities and excitation spectra of light nuclei with quantified uncertainties. In conclusion: The new interaction will enable comprehensive and fully quantified studies of structure and reactions aspects of nuclei from the psd region of the nuclear chart.« less
Proton Radii of 4,6,8He Isotopes from High-Precision Nucleon-Nucleon Interactions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Caurier, E; Navratil, P
2005-11-16
Recently, precision laser spectroscopy on {sup 6}He atoms determined accurately the isotope shift between {sup 4}He and {sup 6}He and, consequently, the charge radius of {sup 6}He. A similar experiment for {sup 8}He is under way. We have performed large-scale ab initio calculations for {sup 4,6,8}He isotopes using high-precision nucleon-nucleon (NN) interactions within the no-core shell model (NCSM) approach. With the CD-Bonn 2000 NN potential we found point-proton root-mean-square (rms) radii of {sup 4}He and {sup 6}He 1.45(1) fm and 1.89(4), respectively, in agreement with experiment and predict the {sup 8}He point proton rms radius to be 1.88(6) fm. Atmore » the same time, our calculations show that the recently developed nonlocal INOY NN potential gives binding energies closer to experiment, but underestimates the charge radii.« less
Nucleon-nucleon interactions from dispersion relations: Elastic partial waves
NASA Astrophysics Data System (ADS)
Albaladejo, M.; Oller, J. A.
2011-11-01
We consider nucleon-nucleon (NN) interactions from chiral effective field theory. In this work we restrict ourselves to the elastic NN scattering. We apply the N/D method to calculate the NN partial waves taking as input the one-pion exchange discontinuity along the left-hand cut. This discontinuity is amenable to a chiral power counting as discussed by Lacour, Oller, and Meißner [Ann. Phys. (NY)APNYA60003-491610.1016/j.aop.2010.06.012 326, 241 (2011)], with one-pion exchange as its leading order contribution. The resulting linear integral equation for a partial wave with orbital angular momentum ℓ≥2 is solved in the presence of ℓ-1 constraints, so as to guarantee the right behavior of the D- and higher partial waves near threshold. The calculated NN partial waves are based on dispersion relations and are independent of regulator. This method can also be applied to higher orders in the calculation of the discontinuity along the left-hand cut and extended to triplet coupled partial waves.
Hard Break-Up of Two-Nucleons and QCD Dynamics of NN Interaction
NASA Astrophysics Data System (ADS)
Sargsian, Misak
2008-10-01
We discus recent developments in theory of high energy two-body break-up of few-nucleon systems. The characteristics of these reactions are such that the hard two-body quasielastic subprocess can be clearly separated from the accompanying soft subprocesses. We discuss in details the hard rescattering model (HRM) in which hard photodisintegration develops in two stages. At first, photon knocks-out an energetic quark which rescatters subsequently with a quark of the other nucleon. The latter provides a mechanism of sharing the initial high momentum of the photon between two outgoing nucleons. This final state hard rescattering can be expressed through the hard NN scattering amplitude. Within HRM we discuss hard break-up reactions involving D and 3He targets and demonstrate how these reactions are sensitive to the dynamics of hard pn and pp interaction. Another development of HRM is the prediction of new helicity selection mechanism for hard two-body reactions, which was apparently confirmed in the recent JLab experiment.
NASA Astrophysics Data System (ADS)
Melson, Tobias; Janka, Hans-Thomas; Bollig, Robert; Hanke, Florian; Marek, Andreas; Müller, Bernhard
2015-08-01
Interactions with neutrons and protons play a crucial role for the neutrino opacity of matter in the supernova core. Their current implementation in many simulation codes, however, is rather schematic and ignores not only modifications for the correlated nuclear medium of the nascent neutron star, but also free-space corrections from nucleon recoil, weak magnetism, or strange quarks, which can easily add up to changes of several 10% for neutrino energies in the spectral peak. In the Garching supernova simulations with the Prometheus-Vertex code, such sophistications have been included for a long time except for the strange-quark contributions to the nucleon spin, which affect neutral-current neutrino scattering. We demonstrate on the basis of a 20 {M}⊙ progenitor star that a moderate strangeness-dependent contribution of {g}{{a}}{{s}}=-0.2 to the axial-vector coupling constant {g}{{a}}≈ 1.26 can turn an unsuccessful three-dimensional (3D) model into a successful explosion. Such a modification is in the direction of current experimental results and reduces the neutral-current scattering opacity of neutrons, which dominate in the medium around and above the neutrinosphere. This leads to increased luminosities and mean energies of all neutrino species and strengthens the neutrino-energy deposition in the heating layer. Higher nonradial kinetic energy in the gain layer signals enhanced buoyancy activity that enables the onset of the explosion at ˜300 ms after bounce, in contrast to the model with vanishing strangeness contributions to neutrino-nucleon scattering. Our results demonstrate the close proximity to explosion of the previously published, unsuccessful 3D models of the Garching group.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guler, Hayg
2003-12-17
In the framework of quantum chromodynamics, the nucleon is made of three valence quarks surrpounded by a sea of gluons and quark-antiquark pairs. Only the only lightest quarks (u, d and s) contribute significantly to the nucleon properties. In Go we using the property of weak interaction to violate parity symmetry, in order to determine separately the contributions of the three types of quarks to nucleon form factors. The experiment, which takes place at Thomas Jefferson laboratory (USA), aims at measuring parity violation asymmetry in electron-proton scattering. By doing several measurements at different momentum squared of the exchanged photons andmore » for different kinematics (forward angle when the proton is detected and backward angle it will be the electron) will permit to determine separately strange quarks electric and magnetic contributions to nucleon form factors. To extract an asymmetry with small errors, it is necessary to correct all the beam parameters, and to have high enough counting rates in detectors. A special electronics was developed to treat information coming from 16 scintillator pairs for each of the 8 sectors of the Go spectrometer. A complete calculation of radiative corrections has been clone and Monte Carlo simulations with the GEANT program has permitted to determine the shape of the experimental spectra including inelastic background. This work will allow to do a comparison between experimental data and theoretical calculations based on the Standard Model.« less
Korover, Igor; Muangma, Navaphon; Hen, Or; ...
2014-07-01
We studied simultaneously the 4He(e,e'p), 4He(e,e'pp), and 4He(e,e'pn) reactions at Q 2=2 [GeV/c] 2 and x B >1, for a (e,e'p) missing-momentum range of 400 to 830 MeV/c. The knocked-out proton was detected in coincidence with a proton or neutron recoiling almost back to back to the missing momentum, leaving the residual A=2 system at low excitation energy. These data were used to identify two-nucleon short-range correlated pairs and to deduce their isospin structure as a function of missing momentum in a region where the nucleon-nucleon force is expected to change from predominantly tensor to repulsive. Neutron-proton pairs dominate themore » high-momentum tail of the nucleon momentum distributions, but their abundance is reduced as the nucleon momentum increases beyond ~500 MeV/c. The extracted fraction of proton-proton pairs is small and almost independent of the missing momentum in the range we studied. Our data are compared with ab-initio calculations of two-nucleon momentum distributions in 4He.« less
2014-05-06
CAPE CANAVERAL, Fla. -- After arriving by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida, the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, were offloaded in their containers. They were transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and is being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge has arrived at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. The segments are being offloaded in their containers for transport to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-08
CAPE CANAVERAL, Fla. -- Inside the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the upper stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being removed from its transportation container. The upper stage, along with the port booster and spacecraft adapter arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and were transported to the HIF. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The upper stage and spacecraft adapter arrived with the booster on a barge at the U.S. Army Outpost wharf at Port Canaveral, and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-08
CAPE CANAVERAL, Fla. -- Inside the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the upper stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being prepared for removal from its transportation container. The upper stage, along with the port booster and spacecraft adapter arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and were transported to the HIF. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- After arriving by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida, the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, were offloaded in their containers. They are being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge has arrived at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. The segments are being offloaded in their containers for transport to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and is being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- After arriving by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida, the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, were offloaded in their containers. They are being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida for uncrating. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida for uncrating. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge has arrived at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They are being offloaded in their containers for transport to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge has arrived at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They are being offloaded in their containers for transport to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge has arrived at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They are being offloaded in their containers for transport to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-08
CAPE CANAVERAL, Fla. -- Inside the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the upper stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being prepared for removal from its transportation container. The upper stage, along with the port booster and spacecraft adapter arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and were transported to the HIF. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge has arrived at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They are being offloaded in their containers for transport to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- After arriving by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida, the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, were offloaded in their containers. They are being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge arrives at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They will be offloaded in their containers and transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- After arriving by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida, the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, were offloaded in their containers. They are being transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge arrives at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They will be offloaded in their containers and transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- A barge arrives at the U.S. Army Outpost wharf at Port Canaveral in Florida, carrying the second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft. They will be offloaded in their containers and transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, is being offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida for uncrating. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- The port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and will be transported to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The upper stage and spacecraft adapter arrived with the booster on a barge at the U.S. Army Outpost wharf at Port Canaveral, and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Orion EFT-1 Cavity Heating Tile Experiments and Environment Reconstruction
NASA Technical Reports Server (NTRS)
Salazar, Giovanni; Amar, Adam; Oliver, Brandon; Hyatt, Andrew; Rezin, Marc
2016-01-01
Developing aerothermodynamic environments for deep cavities, such as those produced by micrometeoroids and orbital debris impacts, poses a great challenge for engineers. In order to assess existing cavity heating models, two one-inch diameter cavities were flown on the Orion Multi-Purpose Crew Vehicle during Exploration Flight Test 1 (EFT1). These cavities were manufactured with depths of 1.0 in and 1.4 in, and they were both instrumented. Instrumentation included surface thermocouples upstream, downstream and within the cavities, and additional thermocouples at the TPS-structure interface. This paper will present the data obtained, and comparisons with computational predictions will be shown. Additionally, the development of a 3D material thermal model will be described, which will be used to account for the three-dimensionality of the problem when interpreting the data. Furthermore, using a multi-dimensional inverse heat conduction approach, a reconstruction of a time- and space-dependent flight heating distribution during EFT1 will be presented. Additional discussions will focus on instrumentation challenges and calibration techniques specific to these experiments. The analysis shown will highlight the accuracies and/or deficiencies of current computational techniques to model cavity flows during hypersonic re-entry.
Light-Nuclei Spectra from Chiral Dynamics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piarulli, M.; Baroni, A.; Girlanda, L.
In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods in order to test to what extent the chiral effective field theory framework impacts our knowledge of few- and many-body systems. Here in this Letter, we present Green’s function Monte Carlo calculations of light nuclei based on the family of local two-body interactions presented by our group in a previous paper in conjunction with chiral three-body interactions fitted to bound- and scattering-state observables in the three-nucleon sector. These interactions include Δ intermediate states in their two-pion-exchange components. We obtain predictions for the energy levelsmore » and level ordering of nuclei in the mass range A=4–12, accurate to ≤2% of the binding energy, in very satisfactory agreement with experimental data.« less
Light-Nuclei Spectra from Chiral Dynamics
Piarulli, M.; Baroni, A.; Girlanda, L.; ...
2018-02-01
In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods in order to test to what extent the chiral effective field theory framework impacts our knowledge of few- and many-body systems. Here in this Letter, we present Green’s function Monte Carlo calculations of light nuclei based on the family of local two-body interactions presented by our group in a previous paper in conjunction with chiral three-body interactions fitted to bound- and scattering-state observables in the three-nucleon sector. These interactions include Δ intermediate states in their two-pion-exchange components. We obtain predictions for the energy levelsmore » and level ordering of nuclei in the mass range A=4–12, accurate to ≤2% of the binding energy, in very satisfactory agreement with experimental data.« less
Electric field tomography for contactless imaging of resistivity in biomedical applications.
Korjenevsky, A V
2004-02-01
The technique of contactless imaging of resistivity distribution inside conductive objects, which can be applied in medical diagnostics, has been suggested and analyzed. The method exploits the interaction of a high-frequency electric field with a conductive medium. Unlike electrical impedance tomography, no electric current is injected into the medium from outside. The interaction is accompanied with excitation of high-frequency currents and redistribution of free charges inside the medium leading to strong and irregular perturbation of the field's magnitude outside and inside the object. Along with this the considered interaction also leads to small and regular phase shifts of the field in the area surrounding the object. Measuring these phase shifts using a set of electrodes placed around the object enables us to reconstruct the internal structure of the medium. The basics of this technique, which we name electric field tomography (EFT), are described, simple analytical estimations are made and requirements for measuring equipment are formulated. The realizability of the technique is verified by numerical simulations based on the finite elements method. Results of simulation have confirmed initial estimations and show that in the case of EFT even a comparatively simple filtered backprojection algorithm can be used for reconstructing the static resistivity distribution in biological tissues.
Episodic and Semantic Memory Contribute to Familiar and Novel Episodic Future Thinking.
Wang, Tong; Yue, Tong; Huang, Xi Ting
2016-01-01
Increasing evidence indicates that episodic future thinking (EFT) relies on both episodic and semantic memory; however, event familiarity may importantly affect the extent to which episodic and semantic memory contribute to EFT. To test this possibility, two behavioral experiments were conducted. In Experiment 1, we directly compared the proportion of episodic and semantic memory used in an EFT task. The results indicated that more episodic memory was used when imagining familiar future events compared with novel future events. Conversely, significantly more semantic memory was used when imagining novel events compared with familiar events. Experiment 2 aimed to verify the results of Experiment 1. In Experiment 2, we found that familiarity moderated the effect of priming the episodic memory system on EFT; particularly, it increased the time required to construct a standard familiar episodic future event, but did not significantly affect novel episodic event reaction time. Collectively, these findings support the hypothesis that event familiarity importantly moderates episodic and semantic memory's contribution to EFT.
Shahar, Ben
2014-01-01
Emotion-focused therapy (EFT) is an integrative and experiential treatment approach that views emotions as fundamentally adaptive and privileges attention to, and exploration of, emotional experiences. EFT has been demonstrated to be efficacious with depression, interpersonal trauma and marital discord, but application to anxiety disorders is in its initial stages. The purpose of this paper is to present the main principles of using EFT with socially anxious patients and to make the case that EFT is particularly well suited for working with this patient group. The primary change processes in EFT for social anxiety include improving emotion awareness, reducing experiential avoidance and the activation and transformation of shame that underlies the symptomatic anxiety. Such processes lead to less self-criticism, to more self-compassion and self-soothing and to a more favourable perception of the self. A case example is used to illustrate how these principles were applied with a socially anxious patient. Copyright © 2013 John Wiley & Sons, Ltd.
New Measurements of High-Momentum Nucleons and Short-Range Structures in Nuclei
Fomin, N.; Arrington, J.; Asaturyan, R.; ...
2012-02-01
We present new, high-Q 2 measurements of inclusive electron scattering from high-momentum nucleons in nuclei. This yields an improved extraction of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data extend to the kinematic regime where three-nucleon correlations are expected to dominate and we observe significantly greater strength in this region than previous measurements.
Enhanced Freight Tracking System: Increased Visibility for the Future
2009-11-01
personnel queried the Enhanced Freight Tracking System ( EFTS ). The EFTS records showed that the items arrived at the port of a neighboring country two weeks...humanitarian missions to continue uninterrupted, potentially saving hundreds of lives. Because the EFTS provides precise shipment status data to mission...33 billion. In addition to materiel coming from Department of Defense (DOD) stock , the U.S. Government (USG) is procuring from domestic and
Setting limits on Effective Field Theories: the case of Dark Matter
NASA Astrophysics Data System (ADS)
Pobbe, Federico; Wulzer, Andrea; Zanetti, Marco
2017-08-01
The usage of Effective Field Theories (EFT) for LHC new physics searches is receiving increasing attention. It is thus important to clarify all the aspects related with the applicability of the EFT formalism in the LHC environment, where the large available energy can produce reactions that overcome the maximal range of validity, i.e. the cutoff, of the theory. We show that this does not forbid to set rigorous limits on the EFT parameter space through a modified version of the ordinary binned likelihood hypothesis test, which we design and validate. Our limit-setting strategy can be carried on in its full-fledged form by the LHC experimental collaborations, or performed externally to the collaborations, through the Simplified Likelihood approach, by relying on certain approximations. We apply it to the recent CMS mono-jet analysis and derive limits on a Dark Matter (DM) EFT model. DM is selected as a case study because the limited reach on the DM production EFT Wilson coefficient and the structure of the theory suggests that the cutoff might be dangerously low, well within the LHC reach. However our strategy can also be applied, if needed, to EFT's parametrising the indirect effects of heavy new physics in the Electroweak and Higgs sectors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frusciante, Noemi; Papadomanolakis, Georgios; Silvestri, Alessandra, E-mail: fruscian@iap.fr, E-mail: papadomanolakis@lorentz.leidenuniv.nl, E-mail: silvestri@lorentz.leidenuniv.nl
We present a generalization of the effective field theory (EFT) formalism for dark energy and modified gravity models to include operators with higher order spatial derivatives. This allows the extension of the EFT framework to a wider class of gravity theories such as Hořava gravity. We present the corresponding extended action, both in the EFT and the Arnowitt-Deser-Misner (ADM) formalism, and proceed to work out a convenient mapping between the two, providing a self contained and general procedure to translate a given model of gravity into the EFT language at the basis of the Einstein-Boltzmann solver EFTCAMB. Putting this mappingmore » at work, we illustrate, for several interesting models of dark energy and modified gravity, how to express them in the ADM notation and then map them into the EFT formalism. We also provide for the first time, the full mapping of GLPV models into the EFT framework. We next perform a thorough analysis of the physical stability of the generalized EFT action, in absence of matter components. We work out viability conditions that correspond to the absence of ghosts and modes that propagate with a negative speed of sound in the scalar and tensor sector, as well as the absence of tachyonic modes in the scalar sector. Finally, we extend and generalize the phenomenological basis in terms of α-functions introduced to parametrize Horndeski models, to cover all theories with higher order spatial derivatives included in our extended action. We elaborate on the impact of the additional functions on physical quantities, such as the kinetic term and the speeds of propagation for scalar and tensor modes.« less
Nonperturbative NN scattering in {sup 3}S{sub 1}–{sup 3}D{sub 1} channels of EFT(⁄π)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Ji-Feng, E-mail: jfyang@phy.ecnu.edu.cn
2013-12-15
The closed-form T matrices in the {sup 3}S{sub 1}–{sup 3}D{sub 1} channels of EFT(⁄π) for NN scattering with the potentials truncated at order O(Q{sup 4}) are presented with the nonperturbative divergences parametrized in a general manner. The stringent constraints imposed by the closed form of the T matrices are exploited in the underlying theory perspective and turned into virtues in the implementation of subtractions and the manifestation of power counting rules in nonperturbative regimes, leading us to the concept of EFT scenario. A number of scenarios of the EFT description of NN scattering are compared with PSA data in termsmore » of effective range expansion and {sup 3}S{sub 1} phase shifts, showing that it is favorable to proceed in a scenario with conventional EFT couplings and sophisticated renormalization in order to have large NN scattering lengths. The informative utilities of fine tuning are demonstrated in several examples and naturally interpreted in the underlying theory perspective. In addition, some of the approaches adopted in the recent literature are also addressed in the light of EFT scenario. -- Highlights: •Closed-form unitary T matrices for NN scattering are obtained in EFT(⁄π). •Nonperturbative properties inherent in such closed-form T matrices are explored. •Nonperturbative renormalization is implemented through exploiting these properties. •Unconventional power counting of couplings is shown to be less favored by PSA data. •The ideas about nonperturbative renormalization here might have wider applications.« less
Feinstein, David
2017-01-01
Abstract Background: The manual stimulation of acupuncture points has been combined with components of cognitive and exposure therapies into a clinical and self-help approach known as Emotional Freedom Techniques (EFT). More than 40 clinical trials and four meta-analytic reviews of EFT treatments have demonstrated large effect sizes with a range of conditions, including pain, PTSD (in both civilian and military veteran populations), phobias, anxiety, and depression. Objective: This review describes the approach, with a focus on PTSD in veterans and service members, provides an overview of how EFT is most commonly applied, and outlines obstacles and cautions related to its implementation. Methods: Peer-reviewed clinical trials and meta-analyses of EFT in the treatment of PTSD are assessed to identify the characteristics of the approach that render it suitable for the treatment of PTSD. Results: The literature demonstrates that remediation of PTSD and comorbid conditions is typically accomplished within brief time frames, ranging from one session for phobias to between four and ten sessions for PTSD. Clinical EFT has been shown to regulate stress hormones and limbic function and to improve various neurologic markers of general health. The epigenetic effects of EFT include upregulation of immunity genes and downregulation of inflammation genes. Six dismantling studies have indicated that the acupressure component of EFT is an active ingredient and not placebo. Conclusions: Seven empirically supported strengths of the approach were identified that make it especially suitable for use with veterans and active military: (1) the depth and breadth of treatment effects; (2) the relatively brief timeframes required for successful treatment; (3) the low risk of adverse events; (4) the minimal training time required for the approach to be applied effectively; (5) the simultaneous reduction of physical and psychologic symptoms; (6) the utility and cost-effectiveness of clinical EFT in a large group format; and (7) the method's adaptability to online and telemedicine applications. PMID:28874920
Neutrino-Nucleon Deep Inelastic Scattering in MINERvA
NASA Astrophysics Data System (ADS)
Norrick, Anne; Minerva Collaboration
2015-04-01
Neutrino-Nucleon Deep Inelastic Scattering (DIS) events provide a probe into the structure of the nucleus that cannot be accessed via charged lepton-nucleon interactions. The MINERvA experiment is stationed in the Neutrinos from the Main Injector (NuMI) beam line at Fermi National Accelerator Laboratory. The projected sensitivity of nuclear structure function analyses using MINERvA's suite of nuclear targets (C, CH, Fe and Pb) in the upgraded 6 GeV neutrino energy NuMI beam will be explored, and their impact discussed.
Roy-Steiner-equation analysis of pion-nucleon scattering
NASA Astrophysics Data System (ADS)
Meißner, U.-G.; Ruiz de Elvira, J.; Hoferichter, M.; Kubis, B.
2017-03-01
Low-energy pion-nucleon scattering is relevant for many areas in nuclear and hadronic physics, ranging from the scalar couplings of the nucleon to the long-range part of two-pion-exchange potentials and three-nucleon forces in Chiral Effective Field Theory. In this talk, we show how the fruitful combination of dispersion-theoretical methods, in particular in the form of Roy-Steiner equations, with modern high-precision data on hadronic atoms allows one to determine the pion-nucleon scattering amplitudes at low energies with unprecedented accuracy. Special attention will be paid to the extraction of the pion-nucleon σ-term, and we discuss in detail the current tension with recent lattice results, as well as the determination of the low-energy constants of chiral perturbation theory.
Monte Carlo calculation of the atmospheric antinucleon flux
NASA Astrophysics Data System (ADS)
Djemil, T.; Attallah, R.; Capdevielle, J. N.
2009-12-01
The atmospheric antiproton and antineutron energy spectra are calculated at float altitude using the CORSIKA package in a three-dimensional Monte Carlo simulation. The hadronic interaction is treated by the FLUKA code below 80 GeV/nucleon and NEXUS elsewhere. The solar modulation which is described by the force field theory and the geomagnetic effects are taken into account. The numerical results are compared with the BESS-2001 experimental data.
Understanding the nucleon as a Borromean bound-state
Segovia, Jorge; Roberts, Craig D.; Schmidt, Sebastian M.
2015-08-20
Analyses of the three valence-quark bound-state problem in relativistic quantum field theory predict that the nucleon may be understood primarily as a Borromean bound-state, in which binding arises mainly from two separate effects. One originates in non-Abelian facets of QCD that are expressed in the strong running coupling and generate confined but strongly-correlated colourantitriplet diquark clusters in both the scalar-isoscalar and pseudovector-isotriplet channels. That attraction is magnified by quark exchange associated with diquark breakup and reformation. Diquark clustering is driven by the same mechanism which dynamically breaks chiral symmetry in the Standard Model. It has numerous observable consequences, the completemore » elucidation of which requires a framework that also simultaneously expresses the running of the coupling and masses in the strong interaction. Moreover, planned experiments are capable of validating this picture.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Golovanov, Georgy
The thesis is devoted to the study of processes with multiple parton interactions (MPI) in a ppbar collision collected by D0 detector at the Fermilab Tevatron collider at sqrt(s) = 1.96 TeV. The study includes measurements of MPI event fraction and effective cross section, a process-independent parameter related to the effective interaction region inside the nucleon. The measurements are done using events with a photon and three hadronic jets in the final state. The measured effective cross section is used to estimate background from MPI for WH production at the Tevatron energy
Advanced Command Destruct System (ACDS) Enhanced Flight Termination System (EFTS)
NASA Technical Reports Server (NTRS)
Tow, David K.
2011-01-01
This presentation provides information on the development, integration, and operational usage of the Enhanced Flight Termination System (EFTS) at NASA Dryden Flight Research Center and Air Force Flight Test Center. The presentation will describe the efforts completed to certify the system and acquire approval for operational usage, the efforts to integrate the system into the NASA Dryden existing flight termination infrastructure, and the operational support of aircraft with EFTS at Edwards AFB.
Brosnan, Mark J; Gwilliam, Lucy R; Walker, Ian
2012-11-01
Enhanced performance upon the Embedded Figures Test (EFT) in individuals with autism spectrum disorder (ASD) has informed psychological theories of the non-social aspects that characterise ASD. The Extreme Male Brain theory of autism proposes that enhanced visual acuity underpins greater attention to detail (assessed by the EFT) which is a prerequisite for Systemizing. To date, however, no study has empirically examined these relationships. 13 males with ASD and 13 male controls were assessed upon tasks argued to reflect these levels of processing. The ASD group were found to have significantly greater visual acuity, EFT performance and Systemizing ability than the control group. However, regression analysis revealed that the strongest relationship was between visual acuity and EFT performance.
Inoue, Takashi; Aoki, Sinya; Doi, Takumi; Hatsuda, Tetsuo; Ikeda, Yoichi; Ishii, Noriyoshi; Murano, Keiko; Nemura, Hidekatsu; Sasaki, Kenji
2013-09-13
Quark mass dependence of the equation of state (EOS) for nucleonic matter is investigated, on the basis of the Brueckner-Hartree-Fock method with the nucleon-nucleon interaction extracted from lattice QCD simulations. We observe saturation of nuclear matter at the lightest available quark mass corresponding to the pseudoscalar meson mass ≃469 MeV. Mass-radius relation of the neutron stars is also studied with the EOS for neutron-star matter from the same nuclear force in lattice QCD. We observe that the EOS becomes stiffer and thus the maximum mass of neutron star increases as the quark mass decreases toward the physical point.
Determining dark matter properties with a XENONnT/LZ signal and LHC Run 3 monojet searches
NASA Astrophysics Data System (ADS)
Baum, Sebastian; Catena, Riccardo; Conrad, Jan; Freese, Katherine; Krauss, Martin B.
2018-04-01
We develop a method to forecast the outcome of the LHC Run 3 based on the hypothetical detection of O (100 ) signal events at XENONnT. Our method relies on a systematic classification of renormalizable single-mediator models for dark matter-quark interactions and is valid for dark matter candidates of spin less than or equal to one. Applying our method to simulated data, we find that at the end of the LHC Run 3 only two mutually exclusive scenarios would be compatible with the detection of O (100 ) signal events at XENONnT. In the first scenario, the energy distribution of the signal events is featureless, as for canonical spin-independent interactions. In this case, if a monojet signal is detected at the LHC, dark matter must have spin 1 /2 and interact with nucleons through a unique velocity-dependent operator. If a monojet signal is not detected, dark matter interacts with nucleons through canonical spin-independent interactions. In a second scenario, the spectral distribution of the signal events exhibits a bump at nonzero recoil energies. In this second case, a monojet signal can be detected at the LHC Run 3; dark matter must have spin 1 /2 and interact with nucleons through a unique momentum-dependent operator. We therefore conclude that the observation of O (100 ) signal events at XENONnT combined with the detection, or the lack of detection, of a monojet signal at the LHC Run 3 would significantly narrow the range of possible dark matter-nucleon interactions. As we argued above, it can also provide key information on the dark matter particle spin.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jaganathen, Y.; Betan, R. M. Id; Michel, N.
Background: The structure of weakly bound and unbound nuclei close to particle drip lines is one of the major science drivers of nuclear physics. A comprehensive understanding of these systems goes beyond the traditional configuration interaction approach formulated in the Hilbert space of localized states (nuclear shell model) and requires an open quantum system description. The complex-energy Gamow shell model (GSM) provides such a framework as it is capable of describing resonant and nonresonant many-body states on equal footing. Purpose: To make reliable predictions, quality input is needed that allows for the full uncertainty quantification of theoretical results. In thismore » study, we carry out the optimization of an effective GSM (one-body and two-body) interaction in the psdf-shell-model space. The resulting interaction is expected to describe nuclei with 5 ≤ A ≲ 12 at the p-sd-shell interface. Method: The one-body potential of the 4He core is modeled by a Woods-Saxon + spin-orbit + Coulomb potential, and the finite-range nucleon-nucleon interaction between the valence nucleons consists of central, spin-orbit, tensor, and Coulomb terms. The GSM is used to compute key fit observables. The χ 2 optimization is performed using the Gauss-Newton algorithm augmented by the singular value decomposition technique. The resulting covariance matrix enables quantification of statistical errors within the linear regression approach. Results: The optimized one-body potential reproduces nucleon- 4He scattering phase shifts up to an excitation energy of 20 MeV. The two-body interaction built on top of the optimized one-body field is adjusted to the bound and unbound ground-state binding energies and selected excited states of the helium, lithium, and beryllium isotopes up to A = 9 . A very good agreement with experimental results was obtained for binding energies. First applications of the optimized interaction include predictions for two-nucleon correlation densities and excitation spectra of light nuclei with quantified uncertainties. In conclusion: The new interaction will enable comprehensive and fully quantified studies of structure and reactions aspects of nuclei from the psd region of the nuclear chart.« less
Roles of NN-interaction components in shell-structure evolution
NASA Astrophysics Data System (ADS)
Umeya, Atsushi; Muto, Kazuo
2016-11-01
Since the importance of the monopole interaction was first emphasized in 1960s, roles of monopole strengths of two-body nucleon-nucleon interaction in shell structure have been discussed. Through the monopole strengths, we study the roles in shell-structure evolution, starting from explicit forms of the interaction. For the tensor component of the interaction, we show the derivation of the relation, (2j> + 1)Vjj> + (2j< + 1)Vjj< = 0, with a detailed manipulation. We show that one-body spin-orbit term appears in the multipole expansion of two-body spin-orbit interaction. Only the spin-orbit components can affect the spin-orbit energy splitting between spin-orbit partners, when the spin-orbit partner orbits are fully occupied.
Dependence of Fusion Barrier Heights on the Difference of Proton and Neutron Radii
NASA Astrophysics Data System (ADS)
Dobrowolski, A.; Pomorski, K.; Bartel, J.
2005-04-01
Using the Skyrme effective nucleon--nucleon interaction together with the semiclassical Extended Thomas--Fermi approach (ETF) we investigate the relative change of the fusion barrier heights for the reaction 16O+208Pb as function of the nuclear proton or neutron radii of the colliding nuclei.
2013-01-01
Background Autism spectrum conditions (ASC) are associated with deficits in social interaction and communication, alongside repetitive, restricted, and stereotyped behavior. ASC is highly heritable. The gamma-aminobutyric acid (GABA)-ergic system has been associated consistently with atypicalities in autism, in both genetic association and expression studies. A key component of the GABA-ergic system is encoded by the GABRB3 gene, which has been previously implicated both in ASC and in individual differences in empathy. Methods In this study, 45 genotyped single nucleotide polymorphisms (SNPs) within GABRB3 were tested for association with Asperger syndrome (AS), and related quantitative traits measured through the following tests: the Empathy Quotient (EQ), the Autism Spectrum Quotient (AQ), the Systemizing Quotient-Revised (SQ-R), the Embedded Figures Test (EFT), the Reading the Mind in the Eyes Test (RMET), and the Mental Rotation Test (MRT). Two-loci, three-loci, four-loci haplotype analyses, and one seven-loci haplotype analysis were also performed in the AS case–control sample. Results Three SNPs (rs7180158, rs7165604, rs12593579) were significantly associated with AS, and two SNPs (rs9806546, rs11636966) were significantly associated with EQ. Two SNP-SNP pairs, rs12438141-rs1035751 and rs12438141-rs7179514, showed significant association with variation in the EFT scores. One SNP-SNP pair, rs7174437-rs1863455, was significantly associated with variation in the MRT scores. Additionally, a few haplotypes, including a 19 kb genomic region that formed a linkage disequilibrium (LD) block in our sample and contained several nominally significant SNPs, were found to be significantly associated with AS. Conclusion The current study confirms the role of GABRB3 as an important candidate gene in both ASC and normative variation in related endophenotypes. PMID:24321478
Benchmark results for few-body hypernuclei
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ruffino, Fabrizio Ferrari; Lonardoni, Diego; Barnea, Nir
2017-03-16
Here, the Non-Symmetrized Hyperspherical Harmonics method (NSHH) is introduced in the hypernuclear sector and benchmarked with three different ab-initio methods, namely the Auxiliary Field Diffusion Monte Carlo method, the Faddeev–Yakubovsky approach and the Gaussian Expansion Method. Binding energies and hyperon separation energies of three- to five-body hypernuclei are calculated by employing the two-body ΛN component of the phenomenological Bodmer–Usmani potential, and a hyperon-nucleon interaction simulating the scattering phase shifts given by NSC97f. The range of applicability of the NSHH method is briefly discussed.
T(T,4He)2n and 3He(3He,4He)2p Reactions and the Energy Dependence of Their Mechanisms
NASA Astrophysics Data System (ADS)
Bacher, Andrew; McNabb, Dennis; Brune, Carl; Sayre, Dan; Hale, Gerry; Frenje, Johan; Gatu Johnson, Maria
2015-10-01
We have studied the T(T,alpha)2n reaction because it is the charge symmetric analog to the 3He(3He,alpha)2p reaction which completes the most direct mode of the p-p chain in stellar interiors. These reactions lead to three-body final states whose energy spectrum shapes are dominated by the strong nucleon-alpha interaction and the weaker nucleon-nucleon interaction. These experiments were done at OMEGA at the University of Rochester and at the NIF at Lawrence Livermore Lab. We will focus on two features: (1) the excitation energy dependence of the reaction mechanism and (2) the center-of-mass energy dependence of the reaction mechanism. At stellar energies (OMEGA and the NIF) we find that the shape of the neutron spectrum peaks in the middle. The n-alpha 1/2-excited state is about two times stronger than the n-alpha 3/2-ground state. For the 3He+3He reaction (at CalTech), the proton spectrum peaks at the high end. The p-alpha 3/2-state is about two times stronger than the 1/2-state. This difference in the spectrum shape is explained by theoretical models which include the interference between the two identical fermions in the final state. At CalTech we have angular distributions of the 3He+3He reaction from 2 MeV to 18 MeV. We see the p-wave strength increasing.
A nucleon-pair and boson coexistent description of nuclei
NASA Astrophysics Data System (ADS)
Dai, Lianrong; Pan, Feng; Draayer, J. P.
2017-07-01
We study a mixture of s-bosons and like-nucleon pairs with the standard pairing interaction outside an inert core. Competition between the nucleon-pairs and s-bosons is investigated in this scenario. The robustness of the BCS-BEC coexistence and crossover phenomena are examined through an analysis of pf-shell nuclei with realistic single-particle energies, in which two configurations with Pauli blocking of nucleon-pair orbits due to the formation of the s-bosons is taken into account. When the nucleon-pair orbits are considered to be independent of the s-bosons, the BCS-BEC crossover becomes smooth, with the number of the s-bosons noticeably more than that of the nucleon-pairs near the half-shell point, a feature that is demonstrated in the pf-shell for several values of the standard pairing interaction strength. As a further test of the robustness of the BCS-BEC coexistence and crossover phenomena in nuclei, results are given for values of even-even 102-130Sn with 100Sn taken as a core and valence neutron pairs confined within the 1d 5/2, 0g 7/2, 1d 3/2, 2s 1/2, 1h 11/2 orbits in the nucleon-pair orbit and the s-boson independent approximation. The results indicate that the B(E2) values are reproduced well. Supported by National Natural Science Foundation of China (11375080, 11675071), the U.S. National Science Foundation (OCI-0904874 and ACI-1516338), U. S. Department of Energy (DE-SC0005248), the Southeastern Universities Research Association, the China-U. S. Theory Institute for Physics with Exotic Nuclei (CUSTIPEN) (DE-SC0009971), and the LSU-LNNU joint research program (9961) is acknowledged
Beyond Collinear Factorization
NASA Astrophysics Data System (ADS)
Neill, Duff
2017-01-01
Collinear factorization is the basis of many collider observables, and is one of the most highly tested bedrocks of QCD. And yet, it reveals a very limited picture of the nucleon, and the internal dynamics of the partons bound within. I will attempt to elucidate what observables do not fall into a naive collinear factorization framework, what sorts of pictures that have been proposed to replace it in these observables, and what one can learn about the nucleon. Time permitting, I will cover new developments in Soft Collinear Effective Field Theory that allow one to discuss and calculate both collinear factorization and spectator interactions on a first principles basis, hopefully paving the way to investigate the whole coherent structure of the nucleon, not just a single lucky parton involved in the hard interaction.
Competencies: Fuzzy Concepts to Context. Symposium.
ERIC Educational Resources Information Center
2002
This document contains three papers from a symposium titled "Competence: Fuzzy Concepts to Context.""Sales Superstars: Defining Competencies Needed for Sales Performance" (Darlene Russ-Eft, Edward Del Gaizo, Jeannie Moulton, Ruth Pangilinan) discusses a study in which an analysis of 1,688 critical incidents revealed 16…
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower will undergo tests to confirm that they are operating correctly. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower will undergo tests to confirm that they are operating correctly. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2012-11-01
Abbreviations BPC building partner capacity DOD Department of Defense DSCA Defense Security Cooperation Agency EFTS Enhanced Freight Tracking System...SCOs are ready to receive a planned delivery. For both FMS and pseudo-FMS processes, DOD uses the Enhanced Freight Tracking System ( EFTS ), a secure...providing data for this system. The Security Assistance Management Manual recommends that SCOs use the EFTS to maintain awareness of incoming shipments
2011-07-25
testing, the EFTR must be keyed with the same key used to encrypt the Enhanced Flight Termination Systems ( EFTS ) message. To ensure identical keys...required to verify the proper state. e. Procedure. (1) Pull up EFTS graphic user interface (GUI) (Figure 3). (2) Click “Receiver Power On...commanded mode steady state input currents will not exceed their specified values. TOP 05-2-543 25 July 2011 19 Figure 3. EFTS GUIa
Pearson, J L; Ferguson, L R
1989-01-01
Relationships were explored among three measures of spatial ability--the Embedded Figures Test (EFT), the Mental Rotations Test (MRT), and the Differential Aptitude Spatial Relations subtest (DAT)--an environmental cognition task (MAP), American College Testing (ACT) math and English achievement, and gender in a sample of 282 undergraduates. Variance attributable to gender among the spatial tasks ranged from 0.5% in the EFT to 12% in the MRT. Gender accounted for only 1% of the variance in the MAP task. Gender differences were noted in regression analyses; women's math and English achievement scores were both predictive of spatial ability, while for men, only math achievement was predictive of spatial ability. The results were interpreted as substantiating sex role socialization theory of cognitive abilities.
Consistent searches for SMEFT effects in non-resonant dijet events
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alte, Stefan; Konig, Matthias; Shepherd, William
Here, we investigate the bounds which can be placed on generic new-physics contributions to dijet production at the LHC using the framework of the Standard Model Effective Field Theory, deriving the first consistently-treated EFT bounds from non-resonant high-energy data. We recast an analysis searching for quark compositeness, equivalent to treating the SM with one higher-dimensional operator as a complete UV model. In order to reach consistent, model-independent EFT conclusions, it is necessary to truncate the EFT effects consistently at ordermore » $$1/\\Lambda^2$$ and to include the possibility of multiple operators simultaneously contributing to the observables, neither of which has been done in previous searches of this nature. Furthermore, it is important to give consistent error estimates for the theoretical predictions of the signal model, particularly in the region of phase space where the probed energy is approaching the cutoff scale of the EFT. There are two linear combinations of operators which contribute to dijet production in the SMEFT with distinct angular behavior; we identify those linear combinations and determine the ability of LHC searches to constrain them simultaneously. Consistently treating the EFT generically leads to weakened bounds on new-physics parameters. These constraints will be a useful input to future global analyses in the SMEFT framework, and the techniques used here to consistently search for EFT effects are directly applicable to other off-resonance signals.« less
Burnett, Benjamin J; Altman, Roger B; Ferrao, Ryan; Alejo, Jose L; Kaur, Navdep; Kanji, Joshua; Blanchard, Scott C
2013-05-10
Aminoacyl-tRNA (aa-tRNA) enters the ribosome in a ternary complex with the G-protein elongation factor Tu (EF-Tu) and GTP. EF-Tu·GTP·aa-tRNA ternary complex formation and decay rates are accelerated in the presence of the nucleotide exchange factor elongation factor Ts (EF-Ts). EF-Ts directly facilitates the formation and disassociation of ternary complex. This system demonstrates a novel function of EF-Ts. Aminoacyl-tRNA enters the translating ribosome in a ternary complex with elongation factor Tu (EF-Tu) and GTP. Here, we describe bulk steady state and pre-steady state fluorescence methods that enabled us to quantitatively explore the kinetic features of Escherichia coli ternary complex formation and decay. The data obtained suggest that both processes are controlled by a nucleotide-dependent, rate-determining conformational change in EF-Tu. Unexpectedly, we found that this conformational change is accelerated by elongation factor Ts (EF-Ts), the guanosine nucleotide exchange factor for EF-Tu. Notably, EF-Ts attenuates the affinity of EF-Tu for GTP and destabilizes ternary complex in the presence of non-hydrolyzable GTP analogs. These results suggest that EF-Ts serves an unanticipated role in the cell of actively regulating the abundance and stability of ternary complex in a manner that contributes to rapid and faithful protein synthesis.
Consistent searches for SMEFT effects in non-resonant dijet events
Alte, Stefan; Konig, Matthias; Shepherd, William
2018-01-19
Here, we investigate the bounds which can be placed on generic new-physics contributions to dijet production at the LHC using the framework of the Standard Model Effective Field Theory, deriving the first consistently-treated EFT bounds from non-resonant high-energy data. We recast an analysis searching for quark compositeness, equivalent to treating the SM with one higher-dimensional operator as a complete UV model. In order to reach consistent, model-independent EFT conclusions, it is necessary to truncate the EFT effects consistently at ordermore » $$1/\\Lambda^2$$ and to include the possibility of multiple operators simultaneously contributing to the observables, neither of which has been done in previous searches of this nature. Furthermore, it is important to give consistent error estimates for the theoretical predictions of the signal model, particularly in the region of phase space where the probed energy is approaching the cutoff scale of the EFT. There are two linear combinations of operators which contribute to dijet production in the SMEFT with distinct angular behavior; we identify those linear combinations and determine the ability of LHC searches to constrain them simultaneously. Consistently treating the EFT generically leads to weakened bounds on new-physics parameters. These constraints will be a useful input to future global analyses in the SMEFT framework, and the techniques used here to consistently search for EFT effects are directly applicable to other off-resonance signals.« less
Low energy peripheral scaling in nucleon-nucleon scattering and uncertainty quantification
NASA Astrophysics Data System (ADS)
Ruiz Simo, I.; Amaro, J. E.; Ruiz Arriola, E.; Navarro Pérez, R.
2018-03-01
We analyze the peripheral structure of the nucleon-nucleon interaction for LAB energies below 350 MeV. To this end we transform the scattering matrix into the impact parameter representation by analyzing the scaled phase shifts (L + 1/2) δ JLS (p) and the scaled mixing parameters (L + 1/2)ɛ JLS (p) in terms of the impact parameter b = (L + 1/2)/p. According to the eikonal approximation, at large angular momentum L these functions should become an universal function of b, independent on L. This allows to discuss in a rather transparent way the role of statistical and systematic uncertainties in the different long range components of the two-body potential. Implications for peripheral waves obtained in chiral perturbation theory interactions to fifth order (N5LO) or from the large body of NN data considered in the SAID partial wave analysis are also drawn from comparing them with other phenomenological high-quality interactions, constructed to fit scattering data as well. We find that both N5LO and SAID peripheral waves disagree more than 5σ with the Granada-2013 statistical analysis, more than 2σ with the 6 statistically equivalent potentials fitting the Granada-2013 database and about 1σ with the historical set of 13 high-quality potentials developed since the 1993 Nijmegen analysis.
BEC-BCS crossover and the liquid-gas phase transition in hot and dense nuclear matter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin Meng; Urban, Michael; Schuck, Peter
2010-08-15
The effect of nucleon-nucleon correlations in symmetric nuclear matter at finite temperature is studied beyond BCS theory. Starting from a Hartree-Fock description of nuclear matter with the Gogny effective interaction, we add correlations corresponding to the formation of preformed pairs and scattering states above the superfluid critical temperature within the in-medium T-matrix approach, which is analogous to the Nozieres-Schmitt-Rink theory. We calculate the critical temperature for a BEC superfluid of deuterons, of a BCS superfluid of nucleons, and in the crossover between these limits. The effect of the correlations on thermodynamic properties (equation of state, energy, entropy) and the liquid-gasmore » phase transition is discussed. Our results show that nucleon-nucleon correlations beyond BCS play an important role for the properties of nuclear matter, especially in the low-density region.« less
Magnetic Polarizability of Virtual (s\\bar{s}) and (c\\bar{c}) Pairs in the Nucleon
NASA Astrophysics Data System (ADS)
Filip, Peter
2017-12-01
We suggest 3 P 0 quantum state of virtual (s\\bar{s}) pairs in the nucleon can be polarised by the internal fields permeating the volume of the nucleon (proton or neutron). Due to the quadratic Zeeman interaction, 3 P 0 wavefunction of virtual (q\\bar{q}) pairs acquires the admixture of 1 P 10 quantum state in the magnetic field, which generates the antiparallel polarization of s and \\bar{s} quarks (in the nucleon). Considering the internal magnetic fields of neutron and proton (originating from their measured magnetic dipole moments), we suggest the induced s-quark polarization in the neutron to be of the oposite direction compared to the proton case. We mention the influence of the internal chromo-magnetic fields on the quantum state of (q\\bar{q}) pairs in the nucleon and we discuss also the expected behaviour of virtual (c\\bar{c}) pairs.
Scaling within the spectral function approach
NASA Astrophysics Data System (ADS)
Sobczyk, J. E.; Rocco, N.; Lovato, A.; Nieves, J.
2018-03-01
Scaling features of the nuclear electromagnetic response functions unveil aspects of nuclear dynamics that are crucial for interpreting neutrino- and electron-scattering data. In the large momentum-transfer regime, the nucleon-density response function defines a universal scaling function, which is independent of the nature of the probe. In this work, we analyze the nucleon-density response function of 12C, neglecting collective excitations. We employ particle and hole spectral functions obtained within two distinct many-body methods, both widely used to describe electroweak reactions in nuclei. We show that the two approaches provide compatible nucleon-density scaling functions that for large momentum transfers satisfy first-kind scaling. Both methods yield scaling functions characterized by an asymmetric shape, although less pronounced than that of experimental scaling functions. This asymmetry, only mildly affected by final state interactions, is mostly due to nucleon-nucleon correlations, encoded in the continuum component of the hole spectral function.
NASA Astrophysics Data System (ADS)
Lonardoni, D.; Gandolfi, S.; Lynn, J. E.; Petrie, C.; Carlson, J.; Schmidt, K. E.; Schwenk, A.
2018-04-01
Quantum Monte Carlo methods have recently been employed to study properties of nuclei and infinite matter using local chiral effective-field-theory interactions. In this work, we present a detailed description of the auxiliary field diffusion Monte Carlo algorithm for nuclei in combination with local chiral two- and three-nucleon interactions up to next-to-next-to-leading order. We show results for the binding energy, charge radius, charge form factor, and Coulomb sum rule in nuclei with 3 ≤A ≤16 . Particular attention is devoted to the effect of different operator structures in the three-body force for different cutoffs. The outcomes suggest that local chiral interactions fit to few-body observables give a very good description of the ground-state properties of nuclei up to 16O, with the exception of one fit for the softer cutoff which predicts overbinding in larger nuclei.
Effective operators in a single-j orbital
NASA Astrophysics Data System (ADS)
Derbali, E.; Van Isacker, P.; Tellili, B.; Souga, C.
2018-03-01
We present an analysis of effective operators in the shell model with up to three-body interactions in the Hamiltonian and two-body terms in electromagnetic transition operators when the nucleons are either neutrons or protons occupying a single-j orbital. We first show that evidence for an effective three-body interaction exists in the N = 50 isotones and in the lead isotopes but that the separate components of such interaction are difficult to obtain empirically. We then determine higher-order terms on more microscopic grounds. The starting point is a realistic two-body interaction in a large shell-model space together with a standard one-body transition operator, which, after restriction to the dominant orbital and with use of stationary perturbation theory, are transformed into effective versions with higher-order terms. An application is presented for the lead isotopes with neutrons in the 1{g}9/2 orbital.
Babl, Anna; Grosse Holtforth, Martin; Heer, Sara; Lin, Mu; Stähli, Annabarbara; Holstein, Dominique; Belz, Martina; Egenolf, Yvonne; Frischknecht, Eveline; Ramseyer, Fabian; Regli, Daniel; Schmied, Emma; Flückiger, Christoph; Brodbeck, Jeannette; Berger, Thomas; Caspar, Franz
2016-11-24
This currently recruiting randomized controlled trial investigates the effects of integrating components of Emotion-Focused Therapy (EFT) into Psychological Therapy (PT), an integrative form of cognitive-behavioral therapy in a manner that is directly mirroring common integrative practice in the sense of assimilative integration. Aims of the study are to understand how both, an existing therapy approach as well as the elements to be integrated, are affected by the integration and to clarify the role of emotional processing as a mediator of therapy outcome. A total of 130 adults with a diagnosed unipolar depressive, anxiety or adjustment disorder (seeking treatment at a psychotherapy outpatient clinic) are randomized to either treatment as usual (PT) with integrated emotion-focused components (TAU + EFT) or PT (TAU). Primary outcome variables are psychopathology and symptom severity at the end of therapy and at follow up; secondary outcome variables are interpersonal problems, psychological wellbeing, quality of life, attainment of individual therapy goals, and emotional competency. Furthermore, process variables such as the quality of the therapeutic relationship are studied as well as aptitude-treatment interactions. Variables are assessed at baseline, after 8 and 16 sessions, at the end of therapy, after 25 ± 3 sessions, and at 6, 12 and 36 month follow-up. Underlying mechanisms of change are investigated. Statistical analyses will be conducted using the appropriate multilevel approaches, mainly two-level regression and growth analysis. The results of this study will indicate whether the integration of emotion-focused elements into treatment as usual increases the effectiveness of Psychological Therapy. If advantages are found, which may be limited to particular variables or subgroups of patients, recommendations for a systematic integration, and caveats if also disadvantages are detected, can be formulated. On a more abstract level, a cognitive behavioral (represented by PT) and humanistic/experiential (represented by EFT) approach will be integrated. It must be emphasized that mimicking common practice in the development and continued education of psychotherapists, EFT is not integrated as a whole, but only elements of EFT that are considered particularly important, and can be trained in an 8-day training plus supervision of therapies. ClinicalTrials.gov, NCT02822443 , 22 June 2016, retrospectively registered.
Fernandes-Cardoso, A; Santos-Furtado, M; Grindler, J; Ferreira, L A; Andrade, J L; Santo, M A
2017-08-01
Epicardial fat (EF) is increased in obesity and has important interactions with atrial and ventricular myocardium. Most of the evidence in this scenario can be confused by the presence of comorbidities such as hypertension, diabetes and dyslipidemia, which are very common in this population. The influence of EF on atrial remodeling and cardiac function demands further investigation on morbidly obese without these comorbidities. We prospectively recruited 20 metabolically healthy morbidly obese and 20 normo-weights controls. The maximum P-wave duration (PWD) was analyzed by 12-lead electrocardiogram. Left atrial diameter (LAD), left ventricular ejection fraction (LVEF) and EF thickness (EFT) were evaluated by two-dimensional echocardiography. The mean of maximum PWD and LAD were significantly larger in the obese group as compared to the control group: 109.55 ± 11.52 ms × 89.38 ± 11.19 ms and 36.12 ± 3.46 mm × 31.45 ± 2.64 mm, (p < 0.0001). The mean LVEF was lower in the obese group: 63.15 ± 4.25% × 66.17 ± 3.37% (p < 0.017). The mean EFT was higher in the obese group: 7.72 ± 1.60 mm × 3.10 ± 0.85 mm (p < 0.0001). A positive correlation was found between EFT and PWD (r = 0.70; p = 0.001) and LAD (r = 0.667; p = 0.001). An inverse correlation was found between EFT and LVEF (r = -0.523; p = 0.001). In a multiple multivariate regression analysis the EFT remains correlated with LAD and LVEF. In a select group of morbidly obese, the excess of EF had a significant impact on atrial remodeling and cardiac function. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.
Electromagnetic and axial-vector form factors of the quarks and nucleon
NASA Astrophysics Data System (ADS)
Dahiya, Harleen; Randhawa, Monika
2017-11-01
In light of the improved precision of the experimental measurements and enormous theoretical progress, the nucleon form factors have been evaluated with an aim to understand how the static properties and dynamical behavior of nucleons emerge from the theory of strong interactions between quarks. We have analyzed the vector and axial-vector nucleon form factors (GE,Mp,n(Q2) and GAp,n(Q2)) using the spin observables in the chiral constituent quark model (χCQM) which has made a significant contribution to the unraveling of the internal structure of the nucleon in the nonperturbative regime. We have also presented a comprehensive analysis of the flavor decomposition of the form factors (GEq(Q2), GMq(Q2) and GAq(Q2) for q = u,d,s) within the framework of χCQM with emphasis on the extraction of the strangeness form factors which are fundamental to determine the spin structure and test the chiral symmetry breaking effects in the nucleon. The Q2 dependence of the vector and axial-vector form factors of the nucleon has been studied using the conventional dipole form of parametrization. The results are in agreement with the available experimental data.
Measurement of Two- and Three-Nucleon Short-Range Correlation Probabilities in Nuclei
NASA Astrophysics Data System (ADS)
Egiyan, K. S.; Dashyan, N. B.; Sargsian, M. M.; Strikman, M. I.; Weinstein, L. B.; Adams, G.; Ambrozewicz, P.; Anghinolfi, M.; Asavapibhop, B.; Asryan, G.; Avakian, H.; Baghdasaryan, H.; Baillie, N.; Ball, J. P.; Baltzell, N. A.; Batourine, V.; Battaglieri, M.; Bedlinskiy, I.; Bektasoglu, M.; Bellis, M.; Benmouna, N.; Biselli, A. S.; Bonner, B. E.; Bouchigny, S.; Boiarinov, S.; Bradford, R.; Branford, D.; Brooks, W. K.; Bültmann, S.; Burkert, V. D.; Bultuceanu, C.; Calarco, J. R.; Careccia, S. L.; Carman, D. S.; Carnahan, B.; Chen, S.; Cole, P. L.; Coltharp, P.; Corvisiero, P.; Crabb, D.; Crannell, H.; Cummings, J. P.; Sanctis, E. De; Devita, R.; Degtyarenko, P. V.; Denizli, H.; Dennis, L.; Dharmawardane, K. V.; Djalali, C.; Dodge, G. E.; Donnelly, J.; Doughty, D.; Dragovitsch, P.; Dugger, M.; Dytman, S.; Dzyubak, O. P.; Egiyan, H.; Elouadrhiri, L.; Empl, A.; Eugenio, P.; Fatemi, R.; Fedotov, G.; Feuerbach, R. J.; Forest, T. A.; Funsten, H.; Gavalian, G.; Gevorgyan, N. G.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guillo, M.; Guler, N.; Guo, L.; Gyurjyan, V.; Hadjidakis, C.; Hardie, J.; Hersman, F. W.; Hicks, K.; Hleiqawi, I.; Holtrop, M.; Hu, J.; Huertas, M.; Hyde-Wright, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Ito, M. M.; Jenkins, D.; Jo, H. S.; Joo, K.; Juengst, H. G.; Kellie, J. D.; Khandaker, M.; Kim, K. Y.; Kim, K.; Kim, W.; Klein, A.; Klein, F. J.; Klimenko, A.; Klusman, M.; Kramer, L. H.; Kubarovsky, V.; Kuhn, J.; Kuhn, S. E.; Kuleshov, S.; Lachniet, J.; Laget, J. M.; Langheinrich, J.; Lawrence, D.; Lee, T.; Livingston, K.; Maximon, L. C.; McAleer, S.; McKinnon, B.; McNabb, J. W.; Mecking, B. A.; Mestayer, M. D.; Meyer, C. A.; Mibe, T.; Mikhailov, K.; Minehart, R.; Mirazita, M.; Miskimen, R.; Mokeev, V.; Morrow, S. A.; Mueller, J.; Mutchler, G. S.; Nadel-Turonski, P.; Napolitano, J.; Nasseripour, R.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Niczyporuk, B. B.; Niyazov, R. A.; O'Rielly, G. V.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Peterson, C.; Pierce, J.; Pivnyuk, N.; Pocanic, D.; Pogorelko, O.; Polli, E.; Pozdniakov, S.; Preedom, B. M.; Price, J. W.; Prok, Y.; Protopopescu, D.; Qin, L. M.; Raue, B. A.; Riccardi, G.; Ricco, G.; Ripani, M.; Ritchie, B. G.; Ronchetti, F.; Rosner, G.; Rossi, P.; Rowntree, D.; Rubin, P. D.; Sabatié, F.; Salgado, C.; Santoro, J. P.; Sapunenko, V.; Schumacher, R. A.; Serov, V. S.; Sharabian, Y. G.; Shaw, J.; Smith, E. S.; Smith, L. C.; Sober, D. I.; Stavinsky, A.; Stepanyan, S.; Stokes, B. E.; Stoler, P.; Strauch, S.; Suleiman, R.; Taiuti, M.; Taylor, S.; Tedeschi, D. J.; Thompson, R.; Tkabladze, A.; Tkachenko, S.; Todor, L.; Tur, C.; Ungaro, M.; Vineyard, M. F.; Vlassov, A. V.; Weygand, D. P.; Williams, M.; Wolin, E.; Wood, M. H.; Yegneswaran, A.; Yun, J.; Zana, L.; Zhang, J.
2006-03-01
The ratios of inclusive electron scattering cross sections of 4He, 12C, and 56Fe to 3He have been measured at 1
Interactions of 13. 6-GeV/nucleon [sup 16]O and [sup 28]Si with carbon, aluminum, and copper
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cumming, J.B.; Chu, Y.Y.; Haustein, P.E.
1993-10-01
Cross sections for forming [sup 24]Na and [sup 18]F by the interactions of 13.6-GeV/nucleon [sup 16]O and [sup 28]Si ions with Al and for forming [sup 24]Na in [sup 16]O interactions with Cu have been measured relative to the cross section for forming [sup 11]C from carbon. The results are generally consistent with energy-independent inclusive cross sections (limiting fragmentation) for heavy ions between [similar to]2 and 13.6 GeV/nucleon. However, comparison of the heavy-ion data with those for high-energy protons indicates a significantly weaker dependence on projectile size than that predicted by the factorization hypothesis for [sigma][sub C]([sup 11]C), [sigma][sub Al]([supmore » 18]F), and [sigma][sub Al]([sup 24]Na). The dependence is slightly stronger in the case of [sigma][sub Cu]([sup 24]Na).« less
NASA Astrophysics Data System (ADS)
Uddin, Kamal
2011-04-01
It is well established that the forces between nucleons are transmitted by meson. The quantitative explanation of nuclear forces in terms of meson theory was extremely tentative & in complete but this theory supplies a valuable point of view . it is fairly certain now that the nucleons within nuclear matter are in a state made rather different from their free condition by the proximity of other nucleons charge independence of nuclear forces demand the existence of neutral meson as amongst the same type of nucleolus (P-P) or (N-N). this force demand the same spin & orbital angular momentum. The exchange interaction in produced by only a neutral meson. The involving mesons without electric charge, that it gives exchanges forces between proton & Neutron & also therefore maintains charge in dependence character. It is evident for the nature of the products that neutral mesons decay by strong & weak interaction both. It means that neutral mesons constituents responsible for the electromagnetic interaction. Dramatically neutral mesons plays important role for electromagnetic & nuclear force both.
NASA Astrophysics Data System (ADS)
Abe, K.; Adam, J.; Aihara, H.; Akiri, T.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Berardi, V.; Berger, B. E.; Berkman, S.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Dewhurst, D.; Di Lodovico, F.; Di Luise, S.; Drapier, O.; Duboyski, T.; Duffy, K.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery-Schrenk, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Iwai, E.; Iwamoto, K.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koshio, Y.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kurjata, R.; Kutter, T.; Lagoda, J.; Lamont, I.; Larkin, E.; Laveder, M.; Lawe, M.; Lazos, M.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Ludovici, L.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Martynenko, S.; Maruyama, T.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Metelko, C.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Missert, A.; Miura, M.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nakadaira, T.; Nakahata, M.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Payne, D.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration
2014-12-01
The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ˜1 GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged νe charged current cross section on carbon is measured to be ⟨σ ⟩ϕ =1.11 ±0.10 (stat)±0.18 (syst)×1 0-38 cm2/nucleon . The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23 ×1 0-38 cm2/nucleon and the GENIE prediction is 1.08 ×1 0-38 cm2/nucleon . The total νe charged current cross-section result is also in agreement with data from the Gargamelle experiment.
Neutron matter at next-to-next-to-next-to-leading order in chiral effective field theory.
Tews, I; Krüger, T; Hebeler, K; Schwenk, A
2013-01-18
Neutron matter presents a unique system for chiral effective field theory because all many-body forces among neutrons are predicted to next-to-next-to-next-to-leading order (N(3)LO). We present the first complete N(3)LO calculation of the neutron matter energy. This includes the subleading three-nucleon forces for the first time and all leading four-nucleon forces. We find relatively large contributions from N(3)LO three-nucleon forces. Our results provide constraints for neutron-rich matter in astrophysics with controlled theoretical uncertainties.
Reductions in pain, depression, and anxiety symptoms after PTSD remediation in veterans.
Church, Dawson
2014-01-01
A randomized controlled trial of veterans with clinical levels of PTSD symptoms found significant improvements after Emotional Freedom Techniques (EFT). Although pain, depression, and anxiety were not the primary targets of treatment, significant improvements in these conditions were noted. Subjects (N = 59) received six sessions of EFT coaching supplementary to primary care. They were assessed using the SA-45, which measures nine mental health symptom domains and also has two general scales measuring the breadth and depth of psychological distress. Anxiety and depression both reduced significantly, as did the breadth and depth of psychological symptoms. Pain decreased significantly during the intervention period (-41%, p < .0001). Subjects were followed up at three and six months, revealing significant relationships between PTSD, depression, and anxiety at several assessment points. At follow-up, pain remained significantly lower than at pretest. The results of this study are consistent with other reports showing that, as PTSD symptoms are reduced, general mental health improves, and pain levels drop. The ability of EFT to produce reliable and long-term gains after relatively brief interventions indicates its utility in reducing the estimated trillion-dollar cost of treating veteran mental health disorders in the coming years. Copyright © 2014 Elsevier Inc. All rights reserved.
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, into the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The port booster joins the other two boosters of the Delta IV Heavy already in the HIF. The upper stage and spacecraft adapter arrived with the booster on a barge at the U.S. Army Outpost wharf at Port Canaveral, and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, into the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The port booster joins the other two boosters of the Delta IV Heavy already in the HIF. The upper stage and spacecraft adapter arrived with the booster on a barge at the U.S. Army Outpost wharf at Port Canaveral, and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. Inside the facility, technicians uncrate the upper stage. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, to Space Launch Complex 37 on Cape Canaveral Air Force Station after it was offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The booster will be transported to the Horizontal Integration Facility, or HIF, at the launch complex. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. Inside the facility, technicians uncrate the upper stage. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, to Space Launch Complex 37 on Cape Canaveral Air Force Station after it was offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The booster will be transported to the Horizontal Integration Facility, or HIF, at the launch complex. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, into the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. The port booster joins the other two boosters of the Delta IV Heavy already in the HIF. The upper stage and spacecraft adapter arrived with the booster on a barge at the U.S. Army Outpost wharf at Port Canaveral, and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-06
CAPE CANAVERAL, Fla. -- The second stage, port booster and spacecraft adapter, the remaining stages for the United Launch Alliance Delta IV Heavy boosters for NASA’s upcoming Exploration Flight Test-1, or EFT-1, mission with the Orion spacecraft, have been transported in their containers to the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida. Inside the facility, technicians uncrate the port booster. The segments arrived by barge at the U.S. Army Outpost wharf at Port Canaveral. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, to Space Launch Complex 37 on Cape Canaveral Air Force Station after it was offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The booster will be transported to the Horizontal Integration Facility, or HIF, at the launch complex. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-08
CAPE CANAVERAL, Fla. -- Inside the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the upper stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been removed from its transportation container and will be lowered onto a cradle. The upper stage, along with the port booster and spacecraft adapter arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and were transported to the HIF. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-07
CAPE CANAVERAL, Fla. -- A transporter for oversize loads carries the port booster for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, to Space Launch Complex 37 on Cape Canaveral Air Force Station after it was offloaded from the barge at the U.S. Army Outpost wharf at Port Canaveral in Florida. The booster will be transported to the Horizontal Integration Facility, or HIF, at the launch complex. The upper stage and spacecraft adapter arrived with the booster and were transported to the HIF on May 6. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
2014-05-08
CAPE CANAVERAL, Fla. -- Inside the Horizontal Integration Facility, or HIF, at Space Launch Complex 37 on Cape Canaveral Air Force Station in Florida, the upper stage for the United Launch Alliance Delta IV Heavy for Exploration Flight Test-1, or EFT-1, has been removed from its transportation container and will be lowered onto a cradle. The upper stage, along with the port booster and spacecraft adapter arrived by barge at the U.S. Army Outpost wharf at Port Canaveral in Florida and were transported to the HIF. At the HIF, all three booster stages will be processed and checked out before being moved to the nearby launch pad and hoisted into position. The spacecraft adapter will connect Orion to the ULA Delta IV, and also will connect Orion to NASA's new rocket, the Space Launch System, on its first mission in 2017. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on EFT-1 is planned for fall 2014. Photo credit: NASA/Kim Shiflett
Development and Application of a Test for Food-Induced Emotions.
Geier, Uwe; Büssing, Arndt; Kruse, Pamela; Greiner, Ramona; Buchecker, Kirsten
2016-01-01
This study aimed to develop a test to measure food-induced emotions suitable for stable food and beverages. All of the experiments were conducted under the conditions of a consumer sensory evaluation according to German standard DIN 10974. Test development included descriptors' derivation and factor analysis as well as a comparison between the new test (empathic food test, EFT) and a hedonic sensory test and an unspecific psychological test, known as a multidimensional mood questionnaire (MDMQ). Nineteen sensory experts derived twelve items using free-choice profiling. After an exploratory factor analyses, ten of the intended twelve items were integrated into two scales. To compare the new questionnaire (EFT) to the MDMQ and a hedonic test, panels of 59 (EFT), 64 (MDMQ) and 63 (hedonic sensory test) untrained individuals described their perceptions after consuming sensorially similar pairs of milk, water, bread and sugar. The benchmark of comparison was the power to discriminate between the food pairs. Test-retest replicability was demonstrated. All three tests presented slight differences in sample preference and effect size depending on the offered products. These findings underscore the need to test new methods with a wide range of products. Further research is needed to investigate the relationship between sensorial perception and emotional response.
Development and Application of a Test for Food-Induced Emotions
Geier, Uwe; Büssing, Arndt; Kruse, Pamela; Greiner, Ramona; Buchecker, Kirsten
2016-01-01
This study aimed to develop a test to measure food-induced emotions suitable for stable food and beverages. All of the experiments were conducted under the conditions of a consumer sensory evaluation according to German standard DIN 10974. Test development included descriptors’ derivation and factor analysis as well as a comparison between the new test (empathic food test, EFT) and a hedonic sensory test and an unspecific psychological test, known as a multidimensional mood questionnaire (MDMQ). Nineteen sensory experts derived twelve items using free-choice profiling. After an exploratory factor analyses, ten of the intended twelve items were integrated into two scales. To compare the new questionnaire (EFT) to the MDMQ and a hedonic test, panels of 59 (EFT), 64 (MDMQ) and 63 (hedonic sensory test) untrained individuals described their perceptions after consuming sensorially similar pairs of milk, water, bread and sugar. The benchmark of comparison was the power to discriminate between the food pairs. Test-retest replicability was demonstrated. All three tests presented slight differences in sample preference and effect size depending on the offered products. These findings underscore the need to test new methods with a wide range of products. Further research is needed to investigate the relationship between sensorial perception and emotional response. PMID:27861503
NASA Astrophysics Data System (ADS)
Aubert, J. J.; Bassompierre, G.; Becks, K. H.; Benchouk, C.; Best, C.; Bird, I. G.; Böhm, E.; de Bouard, X.; Brasse, F. W.; Broll, C.; Brown, S.; Carr, J.; Clifft, R.; Cobb, J. H.; Coignet, G.; Combley, F.; Court, G. R.; D'Agostini, G.; Dau, W. D.; Davies, J. K.; Déclais, Y.; Dosselli, U.; Drees, J.; Edwards, A.; Edwards, M.; Favier, J.; Ferrero, M. I.; Flauger, W.; Forsbach, H.; Gabathuler, E.; Gamet, R.; Gayler, J.; Gerhardt, V.; Gössling, C.; Haas, J.; Hamacher, K.; Hayman, P.; Henckes, M.; Korbel, V.; Landgraf, U.; Leenen, M.; Maire, M.; Mohr, W.; Montgomery, H. E.; Moser, K.; Mount, R. P.; Nagy, E.; Nassalski, J.; Norton, P. R.; McNicholas, J.; Osborne, A. M.; Payre, P.; Peroni, C.; Pessard, H.; Pietrzyk, U.; Rith, K.; Schneegans, M.; Sloan, T.; Stier, H. E.; Stockhausen, W.; Thénard, J. M.; Thompson, J. C.; Urban, L.; Villers, M.; Wahlen, H.; Walley, M.; Williams, D.; Williams, W. S. C.; Williamson, J.; Wimpenny, S.
1985-03-01
The cross sections for J/ψ production have been measured in interactions of 280 GeV μ+ on hydrogen and deuterium (H, D) and also in interactions of 250 GeV μ+ on iron. The single-nucleon cross sections in iron are found to be larger than those in H, D. The mean ratio of the iron to H, D photoproduction cross sections in the range 60 < v < 200 GeV is 1.45 +/-0.12 (statistical) +/-0.22 (systematic error). Within the framework of the photon-gluon fusion model, this indicates that the gluon density per nucleon is ~45% larger in iron than in H, D in the range 0.026 < x < 0.085, on a mass scale Q2eff ~M2J/ψ.
A Study of Multi-Λ Hypernuclei Within Spherical Relativistic Mean-Field Approach
NASA Astrophysics Data System (ADS)
Rather, Asloob A.; Ikram, M.; Usmani, A. A.; Kumar, B.; Patra, S. K.
2017-12-01
This research article is a follow up of an earlier work by M. Ikram et al., reported in Int. J. Mod. Phys. E 25, 1650103 (2016) where we searched for Λ magic numbers in experimentally confirmed doubly magic nucleonic cores in light to heavy mass region (i.e., 16 O-208 P b) by injecting Λ's into them. In the present manuscript, working within the state of the art relativistic mean field theory with the inclusion of Λ N and ΛΛ interaction in addition to nucleon-meson NL 3∗ effective force, we extend the search of lambda magic numbers in multi- Λ hypernuclei using the predicted doubly magic nucleonic cores 292120, 304120, 360132, 370132, 336138, 396138 of the elusive superheavy mass regime. In analogy to well established signatures of magicity in conventional nuclear theory, the prediction of hypernuclear magicities is made on the basis of one-, two- Λ separation energy ( S Λ, S 2Λ) and two lambda shell gaps ( δ 2Λ) in multi- Λ hypernuclei. The calculations suggest that the Λ numbers 92, 106, 126, 138, 184, 198, 240, and 258 might be the Λ shell closures after introducing the Λ's in the elusive superheavy nucleonic cores. The appearance of new lambda shell closures apart from the nucleonic ones predicted by various relativistic and non-relativistic theoretical investigations can be attributed to the relatively weak strength of the spin-orbit coupling in hypernuclei compared to normal nuclei. Further, the predictions made in multi- Λ hypernuclei under study resembles closely the magic numbers in conventional nuclear theory suggested by various relativistic and non-relativistic theoretical models. Moreover, in support of the Λ shell closure, the investigation of Λ pairing energy and effective Λ pairing gap has been made. We noticed a very close agreement of the predicted Λ shell closures with the survey made on the pretext of S Λ, S 2Λ, and δ 2Λ except for the appearance of magic numbers corresponding to Λ = 156 which manifest in Λ effective pairing gap and pairing energy. Also, the lambda single-particle spectrum is analyzed to mark the energy shell gap for further strengthening the predictions made on the basis of separation energies and shell gaps. Lambda and nucleon spin-orbit interactions are analyzed to confirm the reduction in magnitude of Λ spin-orbit interaction compared to the nucleonic case, however the interaction profile is similar in both the cases. Lambda and nucleon density distributions have been investigated to reveal the impurity effect of Λ hyperons which make the depression of central density of the core of superheavy doubly magic nuclei. Lambda skin structure is also seen.
Fuermaier, Anselm B. M.; Tucha, Oliver; Koerts, Janneke; Grabski, Meryem; Lange, Klaus W.; Weisbrod, Matthias; Aschenbrenner, Steffen; Tucha, Lara
2016-01-01
Objectives It has been shown that an increasing number of adults deliberately feign attention deficit hyperactivity disorder (ADHD), which demonstrates the need for new tests designed to detect feigned ADHD. Methods An Embedded Figures Test (EFT) was developed for the detection of feigned ADHD in adulthood. EFT performance of 51 adults with ADHD was compared to the performance of 52 matched healthy individuals, as well as to 268 undergraduate students who were randomly allocated in a simulation design to one of four experimental conditions, i.e. a control group, a naïve simulation group, a symptom-coached simulation group or a test-coached simulation group. Furthermore, an independent sample of 11 adults with ADHD as well as a sample of 17 clinicians experienced in the work with adults with ADHD were assessed for further validation of the EFT. Results The EFT was relatively easy to perform for both patients with ADHD and healthy comparisons as shown by low error rates and non-significant group differences. However, simulation groups differed from patients with ADHD by significant and large effects. An EFT index for the prediction of feigned ADHD was derived based on logistic regression coefficients. Receiver Operating Characteristics (ROC) demonstrated good classification accuracy of feigned ADHD relative to ADHD (AUC = 94.8%), i.e. high sensitivity (88%) and specificity (90%). Conclusions This study supports the utility of the EFT for the detection of feigned adult ADHD. PMID:27732620
Fuermaier, Anselm B M; Tucha, Oliver; Koerts, Janneke; Grabski, Meryem; Lange, Klaus W; Weisbrod, Matthias; Aschenbrenner, Steffen; Tucha, Lara
2016-01-01
It has been shown that an increasing number of adults deliberately feign attention deficit hyperactivity disorder (ADHD), which demonstrates the need for new tests designed to detect feigned ADHD. An Embedded Figures Test (EFT) was developed for the detection of feigned ADHD in adulthood. EFT performance of 51 adults with ADHD was compared to the performance of 52 matched healthy individuals, as well as to 268 undergraduate students who were randomly allocated in a simulation design to one of four experimental conditions, i.e. a control group, a naïve simulation group, a symptom-coached simulation group or a test-coached simulation group. Furthermore, an independent sample of 11 adults with ADHD as well as a sample of 17 clinicians experienced in the work with adults with ADHD were assessed for further validation of the EFT. The EFT was relatively easy to perform for both patients with ADHD and healthy comparisons as shown by low error rates and non-significant group differences. However, simulation groups differed from patients with ADHD by significant and large effects. An EFT index for the prediction of feigned ADHD was derived based on logistic regression coefficients. Receiver Operating Characteristics (ROC) demonstrated good classification accuracy of feigned ADHD relative to ADHD (AUC = 94.8%), i.e. high sensitivity (88%) and specificity (90%). This study supports the utility of the EFT for the detection of feigned adult ADHD.
2017-01-01
Abstract Background: Reports show high rates of post-traumatic stress disorder (PTSD) in Veterans who served in the Gulf Wars. Emotional Freedom Techniques (EFT) comprises an evidence-based practice that is highly effective at reducing symptom severity in Veterans with PTSD. The case report here is of one of the Veterans who participated in a replication study of the first Veteran Stress Research Study conducted by Church et al. Results of that study demonstrated that EFT was highly effective at treating the psychologic symptoms of PTSD. Similar results have been found in the replication study conducted by Geronilla et al. Case: RM is a young Marine Reservist who served in Iraq and returned with PTSD. He participated in the Veteran Stress Project replication study wherein he received 6 sessions of EFT. EFT is explained and a sample treatment session is described. A discussion of some of the changes that have occurred for RM is included. Results: The patient's PTSD scores dropped from a high clinical score of 60 before treatment to 40 after 6 sessions and to a clinical score of 22 at 6 months follow-up. His insomnia, which had been at a clinical level, reduced as did his pain and measures of psychologic distress, as measured in the Symptom Assessment–45 instrument. Conclusion: Six sessions of EFT reduced PTSD scores dramatically and improved RM's life. He continues to use EFT to manage any stress in his life. PMID:28874927
Neurophysiological correlates of relatively enhanced local visual search in autistic adolescents.
Manjaly, Zina M; Bruning, Nicole; Neufang, Susanne; Stephan, Klaas E; Brieber, Sarah; Marshall, John C; Kamp-Becker, Inge; Remschmidt, Helmut; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Fink, Gereon R
2007-03-01
Previous studies found normal or even superior performance of autistic patients on visuospatial tasks requiring local search, like the Embedded Figures Task (EFT). A well-known interpretation of this is "weak central coherence", i.e. autistic patients may show a reduced general ability to process information in its context and may therefore have a tendency to favour local over global aspects of information processing. An alternative view is that the local processing advantage in the EFT may result from a relative amplification of early perceptual processes which boosts processing of local stimulus properties but does not affect processing of global context. This study used functional magnetic resonance imaging (fMRI) in 12 autistic adolescents (9 Asperger and 3 high-functioning autistic patients) and 12 matched controls to help distinguish, on neurophysiological grounds, between these two accounts of EFT performance in autistic patients. Behaviourally, we found autistic individuals to be unimpaired during the EFT while they were significantly worse at performing a closely matched control task with minimal local search requirements. The fMRI results showed that activations specific for the local search aspects of the EFT were left-lateralised in parietal and premotor areas for the control group (as previously demonstrated for adults), whereas for the patients these activations were found in right primary visual cortex and bilateral extrastriate areas. These results suggest that enhanced local processing in early visual areas, as opposed to impaired processing of global context, is characteristic for performance of the EFT by autistic patients.
Neurophysiological correlates of relatively enhanced local visual search in autistic adolescents
Manjaly, Zina M.; Bruning, Nicole; Neufang, Susanne; Stephan, Klaas E.; Brieber, Sarah; Marshall, John C.; Kamp-Becker, Inge; Remschmidt, Helmut; Herpertz-Dahlmann, Beate; Konrad, Kerstin; Fink, Gereon R.
2007-01-01
Previous studies found normal or even superior performance of autistic patients on visuospatial tasks requiring local search, like the Embedded Figures Task (EFT). A well-known interpretation of this is “weak central coherence”, i.e. autistic patients may show a reduced general ability to process information in its context and may therefore have a tendency to favour local over global aspects of information processing. An alternative view is that the local processing advantage in the EFT may result from a relative amplification of early perceptual processes which boosts processing of local stimulus properties but does not affect processing of global context. This study used functional magnetic resonance imaging (fMRI) in 12 autistic adolescents (9 Asperger and 3 high-functioning autistic patients) and 12 matched controls to help distinguish, on neurophysiological grounds, between these two accounts of EFT performance in autistic patients. Behaviourally, we found autistic individuals to be unimpaired during the EFT while they were significantly worse at performing a closely matched control task with minimal local search requirements. The fMRI results showed that activations specific for the local search aspects of the EFT were left-lateralised in parietal and premotor areas for the control group (as previously demonstrated for adults), whereas for the patients these activations were found in right primary visual cortex and bilateral extrastriate areas. These results suggest that enhanced local processing in early visual areas, as opposed to impaired processing of global context, is characteristic for performance of the EFT by autistic patients. PMID:17240169
Measurement of G
NASA Astrophysics Data System (ADS)
Gayou, Olivier
2001-10-01
The measurement of the elastic form factors is a key ingredient to any complete understanding of the internal structure of the nucleons, and ultimately of the strong force. Precise data are essential to impose stringent tests on any QCD-based theory. The electromagnetic interaction provides a unique tool to investigate these form factors. In elastic electron scattering off a proton, the electron interacts with the nucleon exchanging a virtual photon. The electron-photon interaction is fully understood from QED, hence making the hadron vertex the only unknown of the reaction...
NASA Technical Reports Server (NTRS)
Dudkin, V. E; Kovalev, E. E.; Nefedov, N. A.; Antonchik, V. A.; Bogdanov, S. D.; Ostroumov, V. I.; Crawford, H. J.; Benton, E. V.
1995-01-01
A nuclear photographic emulsion method was used to study the charge-state, ionization, and angular characteristics of secondaries produced in inelastic interactions of Fe-56 nuclei at 1.8 GeV/nucleon with H, CNO, and AgBr nuclei. The data obtained are compared with the results of calculations made in terms of the Dubna version of the cascade evaporation model (DCM). The DCM has been shown to satisfactorily describe most of the interaction characteristics for two nuclei in the studied reactions. At the same time, quantitative differences are observed in some cases.
Systematic study of baryons in a three-body quark model
NASA Astrophysics Data System (ADS)
Aslanzadeh, M.; Rajabi, A. A.
2016-09-01
We investigated the structure of baryons within a three-body quark model based on hypercentral approach. We considered an SU(6)-invariant potential consisting of the well-known "Coulomb-plus-linear" potential plus some multipole interactions as V ( x) ∝ x - n with n > 2. Then, through an analytical solution, we obtained the energy eigenvalues and eigenfunctions of the three-body problem and evaluated some observables such as the mass spectrum of light baryons and both the electromagnetic elastic form factors, and the charge radii of nucleons. We compared our results with the experimental data and showed that the present model provides a good description of the observed resonances.
The goldstone and goldstino of supersymmetric inflation
Kahn, Yonatan; Roberts, Daniel A.; Thaler, Jesse
2015-10-01
Here, we construct the minimal effective field theory (EFT) of supersymmetric inflation, whose field content is a real scalar, the goldstone for time-translation breaking, and a Weyl fermion, the goldstino for supersymmetry (SUSY) breaking. The inflating background can be viewed as a single SUSY-breaking sector, and the degrees of freedom can be efficiently parameterized using constrained superfields. Our EFT is comprised of a chiral superfield X NL containing the goldstino and satisfying X 2 NL = 0, and a real superfield B NL containing both the goldstino and the goldstone, satisfying X NL B NL = B 3 NL =more » 0. We match results from our EFT formalism to existing results for SUSY broken by a fluid background, showing that the goldstino propagates with subluminal velocities. The same effect can also be derived from the unitary gauge gravitino action after embedding our EFT in supergravity. If the gravitino mass is comparable to the Hubble scale during inflation, we identify a new parameter in the EFT related to a time-dependent phase of the gravitino mass parameter. We briefly comment on the leading contributions of goldstino loops to inflationary observables.« less
Eclipse-Free-Time Assessment Tool for IRIS
NASA Technical Reports Server (NTRS)
Eagle, David
2012-01-01
IRIS_EFT is a scientific simulation that can be used to perform an Eclipse-Free- Time (EFT) assessment of IRIS (Infrared Imaging Surveyor) mission orbits. EFT is defined to be those time intervals longer than one day during which the IRIS spacecraft is not in the Earth s shadow. Program IRIS_EFT implements a special perturbation of orbital motion to numerically integrate Cowell's form of the system of differential equations. Shadow conditions are predicted by embedding this integrator within Brent s method for finding the root of a nonlinear equation. The IRIS_EFT software models the effects of the following types of orbit perturbations on the long-term evolution and shadow characteristics of IRIS mission orbits. (1) Non-spherical Earth gravity, (2) Atmospheric drag, (3) Point-mass gravity of the Sun, and (4) Point-mass gravity of the Moon. The objective of this effort was to create an in-house computer program that would perform eclipse-free-time analysis. of candidate IRIS spacecraft mission orbits in an accurate and timely fashion. The software is a suite of Fortran subroutines and data files organized as a "computational" engine that is used to accurately predict the long-term orbit evolution of IRIS mission orbits while searching for Earth shadow conditions.
Nuclear dipole polarizability from mean-field modeling constrained by chiral effective field theory
NASA Astrophysics Data System (ADS)
Zhang, Zhen; Lim, Yeunhwan; Holt, Jeremy W.; Ko, Che Ming
2018-02-01
We construct a new Skyrme interaction Skχm* by fitting the equation of state and nucleon effective masses in asymmetric nuclear matter from chiral two- and three-body forces as well as the binding energies of finite nuclei. Employing this interaction to study the electric dipole polarizabilities of 48Ca, 68Ni, 120Sn, and 208Pb in the random-phase approximation, we find that the theoretical predictions are in good agreement with experimentally measured values without additional fine tuning of the Skyrme interaction, thus confirming the usefulness of the new Skyrme interaction in studying the properties of nuclei. We further use this interaction to study the neutron skin thicknesses of 48Ca and 208Pb, and they are found to be consistent with the experimental data.
Charmonium-nucleon interactions from the time-dependent HAL QCD method
NASA Astrophysics Data System (ADS)
Sugiura, Takuya; Ikeda, Yoichi; Ishii, Noriyoshi
2018-03-01
The charmonium-nucleon effective central interactions have been computed by the time-dependent HAL QCD method. This gives an updated result of a previous study based on the time-independent method, which is now known to be problematic because of the difficulty in achieving the ground-state saturation. We discuss that the result is consistent with the heavy quark symmetry. No bound state is observed from the analysis of the scattering phase shift; however, this shall lead to a future search of the hidden-charm pentaquarks by considering channel-coupling effects.
Analyzing power Ay(θ) of n-3He elastic scattering between 1.60 and 5.54 MeV.
Esterline, J; Tornow, W; Deltuva, A; Fonseca, A C
2013-04-12
Comprehensive and high-accuracy n-3He elastic scattering analyzing power Ay(θ) angular distributions were obtained at five incident neutron energies between 1.60 and 5.54 MeV. The data are compared to rigorous four-nucleon calculations using high-precision nucleon-nucleon potential models; three-nucleon force effects are found to be very small. The agreement between data and calculations is fair at the lower energies and becomes less satisfactory with increasing neutron energy. Comparison to p-3He scattering over the same energy range exhibits unexpectedly large isospin effects.
Pairing matrix elements and pairing gaps with bare, effective, and induced interactions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barranco, F.; Bortignon, P.F.; Colo, G.
2005-11-01
The dependence on the single-particle states of the pairing matrix elements of the Gogny force and of the bare low-momentum nucleon-nucleon potential v{sub low-k}--designed so as to reproduce the low-energy observables avoiding the use of a repulsive core--is studied for a typical finite, superfluid nucleus ({sup 120}Sn). It is found that the matrix elements of v{sub low-k} follow closely those of v{sub Gogny} on a wide range of energy values around the Fermi energy e{sub F}, those associated with v{sub low-k} being less attractive. This result explains the fact that around e{sub F} the pairing gap {delta}{sub Gogny} associated withmore » the Gogny interaction (and with a density of single-particle levels corresponding to an effective k mass m{sub k}{approx_equal}0.7 m) is a factor of about 2 larger than {delta}{sub low-k}, being in agreement with {delta}{sub exp}=1.4 MeV. The exchange of low-lying collective surface vibrations among pairs of nucleons moving in time-reversal states gives rise to an induced pairing interaction v{sub ind} peaked at e{sub F}. The interaction (v{sub low-k}+v{sub ind}) Z{sub {omega}} arising from the renormalization of the bare nucleon-nucleon potential and of the single-particle motion ({omega}-mass and quasiparticle strength Z{sub {omega}}) associated with the particle-vibration coupling mechanism, leads to a value of the pairing gap at the Fermi energy {delta}{sub ren} that accounts for the experimental value. An important question that remains to be studied quantitatively is to what extent {delta}{sub Gogny}, which depends on average parameters, and {delta}{sub ren}, which explicitly depends on the parameters describing the (low-energy) nuclear structure, display or not a similar isotopic dependence and whether this dependence is borne out by the data.« less
Search for nucleon decays induced by GUT magnetic monopoles with the MACRO experiment
NASA Astrophysics Data System (ADS)
Ambrosio, M.; Antolini, R.; Auriemma, G.; Bakari, D.; Baldini, A.; Barbarino, G. C.; Barish, B. C.; Battistoni, G.; Becherini, Y.; Bellotti, R.; Bemporad, C.; Bernardini, P.; Bilokon, H.; Bloise, C.; Bower, C.; Brigida, M.; Bussino, S.; Cafagna, F.; Calicchio, M.; Campana, D.; Carboni, M.; Caruso, R.; Cecchini, S.; Cei, F.; Chiarella, V.; Choudhary, B. C.; Coutu, S.; Cozzi, M.; de Cataldo, G.; Dekhissi, H.; de Marzo, C.; de Mitri, I.; Derkaoui, J.; de Vincenzi, M.; di Credico, A.; Erriquez, O.; Favuzzi, C.; Forti, C.; Fusco, P.; Giacomelli, G.; Giannini, G.; Giglietto, N.; Giorgini, M.; Grassi, M.; Grillo, A.; Guarino, F.; Gustavino, C.; Habig, A.; Hanson, K.; Heinz, R.; Iarocci, E.; Katsavounidis, E.; Katsavounidis, I.; Kearns, E.; Kim, H.; Kyriazopoulou, S.; Lamanna, E.; Lane, C.; Levin, D. S.; Lipari, P.; Longley, N. P.; Longo, M. J.; Loparco, F.; Maaroufi, F.; Mancarella, G.; Mandrioli, G.; Manzoor, S.; Margiotta, A.; Marini, A.; Martello, D.; Marzari-Chiesa, A.; Mazziotta, M. N.; Michael, D. G.; Monacelli, P.; Montaruli, T.; Monteno, M.; Mufson, S.; Musser, J.; Nicolò, D.; Nolty, R.; Orth, C.; Osteria, G.; Palamara, O.; Patera, V.; Patrizii, L.; Pazzi, R.; Peck, C. W.; Perrone, L.; Petrera, S.; Pistilli, P.; Popa, V.; Rainò, A.; Reynoldson, J.; Ronga, F.; Rrhioua, A.; Satriano, C.; Scapparone, E.; Scholberg, K.; Sciubba, A.; Serra, P.; Sioli, M.; Sirri, G.; Sitta, M.; Spinelli, P.; Spinetti, M.; Spurio, M.; Steinberg, R.; Stone, J. L.; Sulak, L. R.; Surdo, A.; Tarlè, G.; Togo, V.; Vakili, M.; Walter, C. W.; Webb, R.
2002-12-01
The interaction of a Grand Unification Magnetic Monopole with a nucleon can lead to a barion-number violating process in which the nucleon decays into a lepton and one or more mesons (catalysis of nucleon decay). In this paper we report an experimental study of the effects of a catalysis process in the MACRO detector. Using a dedicated analysis we obtain new magnetic monopole (MM) flux upper limits at the level of \\char1263\\cdot 10^{-16} cm^{-2} s^{-1} sr^{-1} for 1.1\\cdot 10^{-4} le \\vertβ\\vert le 5\\cdot 10^{-3}, based on the search for catalysis events in the MACRO data. We also analyze the dependence of the MM flux limit on the catalysis cross section.
Ernst, Alexandra; Sourty, Marion; Roquet, Daniel; Noblet, Vincent; Gounot, Daniel; Blanc, Frédéric; De Seze, Jérôme; Manning, Liliann
2016-06-01
Increasingly studied, episodic future thought (EFT) impairment negatively affects patients' daily life. Along these lines, working with relapsing-remitting multiple sclerosis (RR-MS) patients, we documented the clinical effectiveness of a mental visual imagery (MVI)-based facilitation programme on EFT impairment related to executive function difficulties. We aimed at improving the characterisation of the cognitive and neural underpinnings of RR-MS patients' EFT amelioration, by exploring the structural and functional brain changes following the MVI programme. Seventeen non-depressed RR-MS patients were recruited and randomly assigned in the (i) experimental group (n=10), who followed the MVI programme or in the control group (n=7), who followed a verbal control programme. Using an adapted version of the Autobiographical Interview to assess EFT, after facilitation, significant improvement was observed in the experimental group only. This was accompanied by increased activation in the prefrontal region during the generation of future events and was positively correlated with grey matter volume increase in this same brain area. Increased activations in the parahippocampal and the middle temporal gyri were also observed in the experimental group in post-facilitation. Likewise, functional connectivity changes were observed in the posterior brain regions after facilitation. Only minor cerebral changes were observed in the control group, likely reflecting practice effects. Our study showed that EFT improvement following the MVI programme led to functional and structural changes in brain regions sustaining contextual processing, visual imagery, the integration and maintenance of multimodal information. Taken together, these findings suggest that a cognitive intervention focusing on scene construction can be efficient to alleviate EFT impairment related to executive dysfunction. As such, this study opens the way to the development of tailor-made rehabilitation programmes using the different cognitive mechanisms involved in EFT. Copyright © 2016 Elsevier Inc. All rights reserved.
Bulatowicz, M; Griffith, R; Larsen, M; Mirijanian, J; Fu, C B; Smith, E; Snow, W M; Yan, H; Walker, T G
2013-09-06
Various theories beyond the standard model predict new particles with masses in the sub-eV range with very weak couplings to ordinary matter. A new P-odd and T-odd interaction between polarized and unpolarized nucleons proportional to K·r is one such possibility, where r is the distance between the nucleons and K is the spin of the polarized nucleon. Such an interaction involving a scalar coupling gs at one vertex and a pseudoscalar coupling gp at the polarized nucleon vertex can be induced by the exchange of spin-0 bosons. We used the NMR cell test station at Northrop Grumman Corporation to search for NMR frequency shifts in polarized 129Xe and 131Xe when a nonmagnetic zirconia rod is moved near the NMR cell. Long (T2∼20 s) spin-relaxation times allow precision measurements of the NMR frequency ratios, which are insensitive to magnetic field fluctuations. Combined with existing theoretical calculations of the neutron spin contribution to the nuclear angular momentum in xenon nuclei, the measurements improve the laboratory upper bound on the product gsgp(n) by 2 orders of magnitude for distances near 1 mm. The sensitivity of this technique can be increased by at least two more orders of magnitude.
Proper medical diagnosis and treatment with computer aided system
NASA Astrophysics Data System (ADS)
Pedowski, Tomasz; Wasiewicz, Piotr; Maciejewski, Ryszard; Wallner, Grzegorz
2009-06-01
Nowadays computers successfully analyze medical data giving results used for futher treatment. Every year we develop new technology which gives us better and more precise diagnose. We chose esophageal manometry (EFT) which has been considered as a "gold standard" test for the evaluation of esophageal motility. EFT allows physicians to get informations about esophageal peristalsis, amplitude and duration of the esophageal contraction and liquid/viscous bolus transit time from mouth through stomach. We examined 80 patients during 2008 year. Everybody got EFT, endoscopy and X-Ray examination. It was important to ask about symptoms which we correlate and connect with data from EFT. We tried to find a good algorithm for this job in order to do a simple and helpful tool for physician to make right diagnose. Connection between data and symptoms seems to be right and clear, but finding a good algorithm for given data is the main problem.
Soleimani, Ali Akbar; Najafi, Maryam; Ahmadi, Khodabakhsh; Javidi, Nasirudin; Hoseini Kamkar, Elnaz; Mahboubi, Mohamad
2015-01-01
Background The purpose of this investigation is to determine the efficacy of emotionally focused couples therapy (EFT-C) on enhancement of marital adjustment in infertile couples. Materials and Methods This was a semi-experimental study with a pre- and post-test design. We selected 30 infertile couples (60 subjects) by purposive sampling. Couples were randomly assigned to two groups, sample and control. Each group consisted of 15 couples who had marital maladjustment and low sexual satisfaction. Couples answered the marital adjustment and sexual satisfaction questionnaires at baseline after which the sample group received 10 sessions of EFT-C. Results Results of pre-test and post-test showed that EFT-C significantly impacted marital adjustment and sexual satisfaction. Conclusion EFT-C had a significant effect on enhancement of satisfaction, cohesion and affectional expression. This approach impacted physical and emotional sexual satisfaction of infertile couples. PMID:26644864
Future DUNE constraints on EFT
NASA Astrophysics Data System (ADS)
Falkowski, Adam; Grilli di Cortona, Giovanni; Tabrizi, Zahra
2018-04-01
In the near future, fundamental interactions at high-energy scales may be most efficiently studied via precision measurements at low energies. A universal language to assemble and interpret precision measurements is the so-called SMEFT, which is an effective field theory (EFT) where the Standard Model (SM) Lagrangian is extended by higher-dimensional operators. In this paper we investigate the possible impact of the DUNE neutrino experiment on constraining the SMEFT. The unprecedented neutrino flux offers an opportunity to greatly improve the current limits via precision measurements of the trident production and neutrino scattering off electrons and nuclei in the DUNE near detector. We quantify the DUNE sensitivity to dimension-6 operators in the SMEFT Lagrangian, and find that in some cases operators suppressed by an O(30) TeV scale can be probed. We also compare the DUNE reach to that of future experiments involving atomic parity violation and polarization asymmetry in electron scattering, which are sensitive to an overlapping set of SMEFT parameters.
Nucleon measurements at the precision frontier
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlson, Carl E.
We comment on nucleon measurements at the precision frontier. As examples of what can be learned, we concentrate on three topics, which are parity violating scattering experiments, the proton radius puzzle, and the symbiosis between nuclear and atomic physics.
Lattice calculation of electric dipole moments and form factors of the nucleon
NASA Astrophysics Data System (ADS)
Abramczyk, M.; Aoki, S.; Blum, T.; Izubuchi, T.; Ohki, H.; Syritsyn, S.
2017-07-01
We analyze commonly used expressions for computing the nucleon electric dipole form factors (EDFF) F3 and moments (EDM) on a lattice and find that they lead to spurious contributions from the Pauli form factor F2 due to inadequate definition of these form factors when parity mixing of lattice nucleon fields is involved. Using chirally symmetric domain wall fermions, we calculate the proton and the neutron EDFF induced by the C P -violating quark chromo-EDM interaction using the corrected expression. In addition, we calculate the electric dipole moment of the neutron using a background electric field that respects time translation invariance and boundary conditions, and we find that it decidedly agrees with the new formula but not the old formula for F3. Finally, we analyze some selected lattice results for the nucleon EDM and observe that after the correction is applied, they either agree with zero or are substantially reduced in magnitude, thus reconciling their difference from phenomenological estimates of the nucleon EDM.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Avakian, Harut; Pisano, Silvia
The Deep Inelastic Scattering (DIS) proved to be a great tool in testing of the theory of strong in- teractions. Semi-Inclusive DIS (SIDIS), with detection of an additional hadron allowed first stud- ies of 3D structure of the nucleon, moving the main focus from testing the QCD to understanding of strong interactions and quark gluon dynamics to address a number of puzzles accumulated in recent years. Detection of two hadrons in SIDIS, which is even more complicated, provides ac- cess to details of quark gluon interactions inaccessible in single-hadron SIDIS, providing a new avenue to study the complex nucleon structure.more » Large acceptance of the CLAS detector at Jef- ferson Lab, allowing detection of two hadrons, produced back-to-back (b2b) in the current and target fragmentation regions, provides a unique possibility to study the nucleon structure in target fragmentation region, and correlations of target and current fragmentation regions« less
Surface-peaked medium effects in the interaction of nucleons with finite nuclei
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguayo, F. J.; Arellano, H. F.
We investigate the asymptotic separation of the optical model potential for nucleon-nucleus scattering in momentum space, where the potential is split into a medium-independent term and another depending exclusively on the gradient of the density-dependent g matrix. This decomposition confines the medium sensitivity of the nucleon-nucleus coupling to the surface of the nucleus. We examine this feature in the context of proton-nucleus scattering at beam energies between 30 and 100 MeV and find that the pn coupling accounts for most of this sensitivity. Additionally, based on this general structure of the optical potential we are able to treat both, themore » medium dependence of the effective interaction and the full mixed density as described by single-particle shell models. The calculated scattering observables agree within 10% with those obtained by Arellano, Brieva, and Love in their momentum-space g-folding approach.« less
Exceptional field theories, superparticles in an enlarged 11D superspace and higher spin theories
NASA Astrophysics Data System (ADS)
Bandos, Igor
2017-12-01
Recently proposed exceptional field theories (EFTs) making manifest the duality E n (n) symmetry, first observed as nonlinearly realized symmetries of the maximal d = 3 , 4 , . . . , 9 supergravity (n = 11 - d) and containing 11D and type IIB supergravity as sectors, were formulated in enlarged spacetimes. In the case of E 7 (7) EFT such an enlarged spacetime can be identified with the bosonic body of the d = 4 central charge superspace Σ (60 | 32), the N = 8 d = 4 superspace completed by 56 additional bosonic coordinates associated to central charges of the maximal d = 4 supersymmetry algebra. In this paper we show how the hypothesis on the relation of all the known E n (n) EFTs, including n = 8, with supersymmetry leads to the conjecture on existence of 11D exceptional field theory living in 11D tensorial central charge superspace Σ (528 | 32) and underlying all the E n (n) EFTs with n = 2 , . . . , 8, and probably the double field theory (DFT). We conjecture the possible form of the section conditions of such an 11D EFT and show that quite generic solutions of these can be generated by superparticle models the ground states of which preserve from one half to all but one supersymmetry. The properties of these superparticle models are briefly discussed. We argue that, upon quantization, their quantum states should describe free massless non-conformal higher spin fields in D = 11. We also discuss some relevant representations of the M-theory superalgebra which, in the present context, describes supersymmetry of the 11D EFT.
Church, Dawson; Stern, Sheri; Boath, Elizabeth; Stewart, Antony; Feinstein, David; Clond, Morgan
2017-01-01
Background High prevalence rates of posttraumatic stress disorder (PTSD) in active military and veterans present a treatment challenge. Many PTSD studies have demonstrated the efficacy and safety of Emotional Freedom Techniques (EFT). Objectives To develop clinical best practice guidelines for the use of EFT to treat PTSD, on the basis of the published literature, practitioner experience, and typical case histories. Methods We surveyed 448 EFT practitioners to gather information on their experiences with PTSD treatment. This included their demographic profiles, prior training, professional settings, use of assessments, and PTSD treatment practices. We used their responses, with the research evidence base, to formulate clinical guidelines applying the “stepped care” treatment model used by the United Kingdom’s National Institute for Health and Clinical Excellence. Results Most practitioners (63%) reported that even complex PTSD can be remediated in 10 or fewer EFT sessions. Some 65% of practitioners found that more than 60% of PTSD clients are fully rehabilitated, and 89% stated that less than 10% of clients make little or no progress. Practitioners combined EFT with a wide variety of other approaches, especially cognitive therapy. Practitioner responses, evidence from the literature, and the results of a meta-analysis were aggregated into a proposed clinical guideline. Conclusion We recommend a stepped care model, with 5 EFT therapy sessions for subclinical PTSD and 10 sessions for clinical PTSD, in addition to group therapy, online self-help resources, and social support. Clients who fail to respond should be referred for appropriate further care. PMID:28678690
NASA Astrophysics Data System (ADS)
Smith, Kathlyn M.; Stynder, Deano D.
2015-05-01
Elandsfontein (EFT) is a Middle Pleistocene archaeological/paleontological site located in the Western Cape Province of South Africa. The largest herbivore in the assemblage is Loxodonta atlantica zulu, an extinct member of the genus that includes modern African elephants. No Elephas recki specimens were recovered at EFT, despite their common occurrence in other regions of Africa at the same time. Because E. recki and L. atlantica molars are similar in appearance, but the two species are traditionally viewed as dominating different regions of Africa during the Pleistocene, isolated molars may on occasions have been assessed to species level on the basis of geography rather than morphology. The last morphologic evaluation of EFT elephants was conducted in the 1970s, and revisiting this issue with new specimens provides added insight into the evolution of elephants in Africa. Reevaluating morphological characteristics of EFT elephant molars, through qualitative and quantitative description and comparison with Middle Pleistocene E. recki recki, L. atlantica atlantica, and L. atlantica zulu molar morphology, corroborates assessment of EFT elephants as L. a. zulu. Two recently discovered, previously undescribed molars from EFT show that molars of L. a. zulu exhibit greater variation in enamel thickness, lamellar frequency, and occlusal surface morphology than previously reported. An update of the Pleistocene biogeography of Loxodonta and Elephas indicates that fossil remains of both are often found at the same localities in eastern Africa. Their rare co-occurrences in the north and south, however, suggest geographic separation of the two genera in at least some regions of Africa, which may have been based on habitat preference.
Salas, Martha M; Brooks, Audrey J; Rowe, Jack E
2011-01-01
Specific phobia is one of the most prevalent anxiety disorders. Emotional Freedom Techniques (EFT) has been shown to improve anxiety symptoms; however, their application to specific phobias has received limited attention. This pilot study examined whether EFT, a brief exposure therapy that combines cognitive and somatic elements, had an immediate effect on the reduction of anxiety and behavior associated with specific phobias. The study utilized a crossover design with participants randomly assigned to either diaphragmatic breathing or EFT as the first treatment. The study was conducted at a regional university in the Southwestern United States. Twenty-two students meeting criteria for a phobic response to a specific stimulus (≥8 on an 11-point subjective units of distress scale). Participants completed a total of five two-minute rounds in each treatment intervention. Study measures included a behavioral approach test (BAT), Subjective Units of Distress Scale (SUDS), and Beck Anxiety Inventory (BAI). Emotional Freedom Techniques significantly reduced phobia-related anxiety (BAI P = .042; SUDS P = .002) and ability to approach the feared stimulus (BAT P = .046) whether presented as an initial treatment or following diaphragmatic breathing. When presented as the initial treatment, the effects of EFT remained through the presentation of the comparison intervention. The efficacy of EFT in treating specific phobias demonstrated in several earlier studies is corroborated by the current investigation. Comparison studies between EFT and the most effective established therapies for treating specific phobias are recommended. Copyright © 2011 Elsevier Inc. All rights reserved.
Beth-Uhlenbeck approach for repulsive interactions between baryons in a hadron gas
NASA Astrophysics Data System (ADS)
Vovchenko, Volodymyr; Motornenko, Anton; Gorenstein, Mark I.; Stoecker, Horst
2018-03-01
The quantum mechanical Beth-Uhlenbeck (BU) approach for repulsive hard-core interactions between baryons is applied to the thermodynamics of a hadron gas. The second virial coefficient a2—the "excluded volume" parameter—calculated within the BU approach is found to be temperature dependent, and it differs dramatically from the classical excluded volume (EV) model result. At temperatures T =100 -200 MeV, the widely used classical EV model underestimates the EV parameter for nucleons at a given value of the nucleon hard-core radius by large factors of 3-4. Previous studies, which employed the hard-core radii of hadrons as an input into the classical EV model, have to be re-evaluated using the appropriately rescaled EV parameters. The BU approach is used to model the repulsive baryonic interactions in the hadron resonance gas (HRG) model. Lattice data for the second- and fourth-order net baryon susceptibilities are described fairly well when the temperature dependent BU baryonic excluded volume parameter corresponds to nucleon hard-core radii of rc=0.25 -0.3 fm. Role of the attractive baryonic interactions is also considered. It is argued that HRG model with a constant baryon-baryon EV parameter vN N≃1 fm3 provides a simple yet efficient description of baryon-baryon interaction in the crossover temperature region.
Cross section parameterizations for cosmic ray nuclei. 1: Single nucleon removal
NASA Technical Reports Server (NTRS)
Norbury, John W.; Townsend, Lawrence W.
1992-01-01
Parameterizations of single nucleon removal from electromagnetic and strong interactions of cosmic rays with nuclei are presented. These parameterizations are based upon the most accurate theoretical calculations available to date. They should be very suitable for use in cosmic ray propagation through interstellar space, the Earth's atmosphere, lunar samples, meteorites, spacecraft walls and lunar and martian habitats.
Nuclear Stability and Nucleon-Nucleon Interactions in Introductory and General Chemistry Textbooks
ERIC Educational Resources Information Center
Millevolte, Anthony
2010-01-01
The nucleus is a highly dense and highly charged substructure of atoms. In the nuclei of all atoms beyond hydrogen, multiple protons are in close proximity to each other in spite of strong electrostatic repulsions between them. The attractive internucleon strong force is described and its origin explained by using a simple quark model for the…
Exclusive Reactions Involving Pions and Nucleons
NASA Technical Reports Server (NTRS)
Norbury, John W.; Blattnig, Steve R.; Tripathi, R. K.
2002-01-01
The HZETRN code requires inclusive cross sections as input. One of the methods used to calculate these cross sections requires knowledge of all exclusive processes contributing to the inclusive reaction. Conservation laws are used to determine all possible exclusive reactions involving strong interactions between pions and nucleons. Inclusive particle masses are subsequently determined and are needed in cross-section calculations for inclusive pion production.
Quark cluster model for deep-inelastic lepton-deuteron scattering
NASA Astrophysics Data System (ADS)
Yen, G.; Vary, J. P.; Harindranath, A.; Pirner, H. J.
1990-10-01
We evaluate the contribution of quasifree nucleon knockout and of inelastic lepton-nucleon scattering in inclusive electron-deuteron reactions at large momentum transfer. We examine the degree of quantitative agreement with deuteron wave functions from the Reid soft-core and Bonn realistic nucleon-nucleon interactions. For the range of data available there is strong sensitivity to the tensor correlations which are distinctively different in these two deuteron models. At this stage of the analyses the Reid soft-core wave function provides a reasonable description of the data while the Bonn wave function does not. We then include a six-quark cluster component whose relative contribution is based on an overlap criterion and obtain a good description of all the data with both interactions. The critical separation at which overlap occurs (formation of six-quark clusters) is taken to be 1.0 fm and the six-quark cluster probability is 4.7% for Reid and 5.4% for Bonn. As a consequence the quark cluster model with either Reid or Bonn wave function describe the SLAC inclusive electron-deuteron scattering data equally well. We then show how additional data would be decisive in resolving which model is ultimately more correct.
Study of 11Li+p elastic scattering using BHF formalism with three body force
NASA Astrophysics Data System (ADS)
Sharma, Manjari; Haider, W.
2018-04-01
In the present work we have analyzed the elastic scattering data of 11Li + p at 62, 68.4 and 75 MeV/nucleon, using the microscopic optical potential calculated within the framework of Brueckner-Hartree-Fock formalism (BHF). The calculation uses Argonne v18 and Urbana v14 inter-nucleon potentials and the Urbana IX (UVIX) model of three body force. The required nucleon-density distributions for 11Li are obtained using the semi-phenomenological model for nuclear density distributions. The optical potential has been obtained by folding the g-matrices as calculated in BHF (with and without three body forces) over the nucleon density distributions. We have used the exact method for calculating both the direct and the exchange parts of the spin-orbit potential. Our results reveal that the spin-orbit potential significantly contributes to 11Li+p elastic scattering at all three incident energies. Further, the calculated spin-orbit potential in BHF is much smaller and more diffused as compared with the phenomenological spin-orbit potential. The analysis reveals that the calculated microscopic optical potentials, with and without three body force using BHF approach with phenomenological form of density distribution, provides satisfactory agreement with the elastic scattering data for 11Li+p.
Matching Pion-Nucleon Roy-Steiner Equations to Chiral Perturbation Theory.
Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meissner, Ulf-G
2015-11-06
We match the results for the subthreshold parameters of pion-nucleon scattering obtained from a solution of Roy-Steiner equations to chiral perturbation theory up to next-to-next-to-next-to-leading order, to extract the pertinent low-energy constants including a comprehensive analysis of systematic uncertainties and correlations. We study the convergence of the chiral series by investigating the chiral expansion of threshold parameters up to the same order and discuss the role of the Δ(1232) resonance in this context. Results for the low-energy constants are also presented in the counting scheme usually applied in chiral nuclear effective field theory, where they serve as crucial input to determine the long-range part of the nucleon-nucleon potential as well as three-nucleon forces.
Matching Pion-Nucleon Roy-Steiner Equations to Chiral Perturbation Theory
NASA Astrophysics Data System (ADS)
Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meißner, Ulf-G.
2015-11-01
We match the results for the subthreshold parameters of pion-nucleon scattering obtained from a solution of Roy-Steiner equations to chiral perturbation theory up to next-to-next-to-next-to-leading order, to extract the pertinent low-energy constants including a comprehensive analysis of systematic uncertainties and correlations. We study the convergence of the chiral series by investigating the chiral expansion of threshold parameters up to the same order and discuss the role of the Δ (1232 ) resonance in this context. Results for the low-energy constants are also presented in the counting scheme usually applied in chiral nuclear effective field theory, where they serve as crucial input to determine the long-range part of the nucleon-nucleon potential as well as three-nucleon forces.
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
2014-08-25
CAPE CANAVERAL, Fla. – The umbilical swing arm for Orion's Exploration Flight Test 1, or EFT-1, has been attached to the uppermost location on the fixed umbilical tower at Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. All three swing arms on the tower are undergoing tests to confirm that they are operating correctly. They are being swung out and closer to the Vertical Integration Facility at the pad. The uppermost swing arm will carry umbilicals that will be mated to Orion's launch abort system and environmental control system. During launch, all three umbilicals will pull away from Orion and the United Launch Alliance Delta IV Heavy rocket at T-0. During the EFT-1 mission, Orion will travel farther into space than any human spacecraft has gone in more than 40 years. The data gathered during the flight will influence design decisions, validate existing computer models and innovative new approaches to space systems development, as well as reduce overall mission risks and costs for later Orion flights. Liftoff of Orion on its first flight test is planned for fall 2014. Photo credit: NASA/Daniel Casper
Stadnik, Y V; Dzuba, V A; Flambaum, V V
2018-01-05
In the presence of P, T-violating interactions, the exchange of axionlike particles between electrons and nucleons in atoms and molecules induces electric dipole moments (EDMs) of atoms and molecules. We perform calculations of such axion-exchange-induced atomic EDMs using the relativistic Hartree-Fock-Dirac method including electron core polarization corrections. We present analytical estimates to explain the dependence of these induced atomic EDMs on the axion mass and atomic parameters. From the experimental bounds on the EDMs of atoms and molecules, including ^{133}Cs, ^{205}Tl, ^{129}Xe, ^{199}Hg, ^{171}Yb^{19}F, ^{180}Hf^{19}F^{+}, and ^{232}Th^{16}O, we constrain the P, T-violating scalar-pseudoscalar nucleon-electron and electron-electron interactions mediated by a generic axionlike particle of arbitrary mass. Our limits improve on existing laboratory bounds from other experiments by many orders of magnitude for m_{a}≳10^{-2} eV. We also place constraints on CP violation in certain types of relaxion models.
Fragmentation Cross Sections of 290 and 400 MeV/nucleon 12C Beamson Elemental Targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zeitlin, C.; Guetersloh, S.; Heilbronn, L.
Charge-changing and fragment production cross sections at 0circ have been obtained for interactions of 290 MeV/nucleon and 400MeV/nucleon carbon beams with C, CH2, Al, Cu, Sn, and Pb targets. Thesebeams are relevant to cancer therapy, space radiation, and the productionof radioactive beams. We compare to previously published results using Cand CH2 targets at similar beam energies. Due to ambiguities arising fromthe presence of multiple fragments on many events, previous publicationshave reported only cross sections for B and Be fragments. In this work wehave extracted cross sections for all fragment species, using dataobtained at three distinct values of angular acceptance, supplementedmore » bydata taken with the detector stack placed off the beam axis. A simulationof the experiment with the PHITS Monte Carlo code shows fair agreementwith the data obtained with the large acceptance detectors, but agreementis poor at small acceptance. The measured cross sections are alsocompared to the predictions of the one-dimensional cross section modelsEPAX2 and NUCFRG2; the latter is presently used in NASA's space radiationtransport calculations. Though PHITS and NUCFRG2 reproduce thecharge-changing cross sections with reasonable accuracy, none of themodels is able to accurately predict the fragment cross sections for allfragment species and target materials.« less
Remarks on non-BPS string amplitudes and their all order α' contact interactions in IIB, IIA
NASA Astrophysics Data System (ADS)
Hatefi, Ehsan
2017-03-01
We explore the entire form of S-Matrix elements of a potential C n-1 Ramond-Ramond (RR) form field, a tachyon and two transverse scalar fields on both world volume and transverse directions of type IIB and IIA superstring theories. Apart from < {V}_{C^{-2}}{V}_{φ^0}{V}_{φ^0}{V}_{T^0}\\rangle the other scattering amplitude, namely < {V}_{C^{-1}}{V}_{φ^{-1}}{V}_{φ^0}{V}_{T^0}\\rangle is also revealed. We then start to compare all singularity structures of symmetric and asymmetric analysis, generating all infinite singularity structures as well as all order α' contact interactions on the whole directions. This leads to deriving various new contact terms and several new restricted Bianchi identities in both type IIB and IIA. It is also shown that just some of the new couplings of type IIB (IIA) string theory can be re-verified in an Effective Field Theory (EFT) by pull-back of branes. To construct the rest of S-matrix elements one needs to first derive restricted world volume (or bulk) Bianchi identities and then discover new EFT couplings in both type IIB and IIA. Finally the presence of commutator of scalar fields inside the exponential of Wess-Zumino action for non-BPS branes has been confirmed as well.
Effective field theory for deformed atomic nuclei
Papenbrock, Thomas F.; Weidenmüller, H. A.
2016-04-13
In this paper, we present an effective field theory (EFT) for a model-independent description of deformed atomic nuclei. In leading order this approach recovers the well-known results from the collective model by Bohr and Mottelson. When higher-order corrections are computed, the EFT accounts for finer details such as the variation of the moment of inertia with the band head and the small magnitudes of interband E2 transitions. Finally, for rotational bands with a finite spin of the band head, the EFT is equivalent to the theory of a charged particle on the sphere subject to a magnetic monopole field.
NASA Technical Reports Server (NTRS)
Tow, David
2010-01-01
This paper discusses the methodology, requirements, tests, and results of the implementation of the current operating capability for the Enhanced Flight Termination System (EFTS) at the National Aeronautics and Space Administration (NASA) Dryden Flight Research Center (DFRC). The implementation involves the development of the EFTS at NASA DFRC starting from the requirements to system safety review to full end to end system testing, and concluding with the acceptance of the system as an operational system. The paper discusses the first operational usage and subsequent flight utilizing EFTS successfully.
Toward an effective field theory approach to reheating
NASA Astrophysics Data System (ADS)
Özsoy, Ogan; Giblin, John T.; Nesbit, Eva; Şengör, Gizem; Watson, Scott
2017-12-01
We investigate whether effective field theory (EFT) approaches, which have been useful in examining inflation and dark energy, can also be used to establish a systematic approach to inflationary reheating. We consider two methods. First, we extend Weinberg's background EFT to the end of inflation and reheating. We establish when parametric resonance and decay of the inflaton occurs, but also find intrinsic theoretical limitations, which make it difficult to capture some reheating models. This motivates us to next consider Cheung et al.'s EFT approach, which instead focuses on perturbations and the symmetry breaking induced by the cosmological background. Adapting the latter approach to reheating implies some new and important differences compared to the EFT of inflation. In particular, there are new hierarchical scales, and we must account for inflaton oscillations during reheating, which lead to discrete symmetry breaking. Guided by the fundamental symmetries, we construct the EFT of reheating, and as an example of its usefulness we establish a new class of reheating models and the corresponding predictions for gravity wave observations. In this paper we primarily focus on the first stages of preheating. We conclude by discussing challenges for the approach and future directions. This paper builds on ideas first proposed in the paper [O. Ozsoy, G. Sengor, K. Sinha, and S. Watson, arXiv:1507.06651.].
House, Dennis
2018-01-01
Clinical Emotional Freedom Techniques (EFT) is an evidence-based treatment for depression and anxiety. The current study sought to elucidate the relationship between posttraumatic stress disorder (PTSD), depression, and anxiety in a nonclinical population. The sample (N = 81) comprised participants at five 2-day EFT workshops. All groups used an EFT protocol called Borrowing Benefits, in which the group facilitator works with a single client while other participants self-apply EFT. Participants were assessed on 9 specific conditions as well as on the breadth (Positive Symptom Total [PST]) and depth (General Symptom Index [GSI]) of psychological distress. Physical pain and addictive cravings were also assessed. Significant reductions were observed in all measures (P < .03). Associations between PST, GSI, and PTSD were significant (P < .026). Participants maintained all gains at 6-month follow-up (P < .02) with the exception of the Hostility subscale, while Cohen’s d = 0.54 indicated a moderate treatment effect for PTSD. The relationship between psychological and physiological conditions identified in this study is consistent with that found in other studies. Group treatment is cost-effective and efficient, and the efficacy of EFT in groups indicates the utility of the Borrowing Benefits technique. PMID:29468884
Maintenance of gains following experiential therapies for depression.
Ellison, Jennifer A; Greenberg, Leslie S; Goldman, Rhonda N; Angus, Lynne
2009-02-01
Follow-up data across an 18-month period are presented for 43 adults who had been randomly assigned and had responded to short-term client-centered (CC) and emotion-focused (EFT) therapies for major depression. Long-term effects of these short-term therapies were evaluated using relapse rates, number of asymptomatic or minimally symptomatic weeks, survival times across an 18-month follow-up, and group comparisons on self-report indices at 6- and 18-month follow-up among those clients who responded to the acute treatment phase. EFT treatment showed superior effects across 18 months in terms of less depressive relapse and greater number of asymptomatic or minimally symptomatic weeks, and the probability of maintaining treatment gains was significantly more likely in the EFT treatment than in the CC treatment. In addition, follow-up self-report results demonstrated significantly greater effects for EFT clients on reduction of depression and improvement of self-esteem, and there were trends in favor of EFT, in comparison with CC, on reduction of general symptom distress and interpersonal problems. Maintenance of treatment gains following an empathic relational treatment appears to be enhanced by the addition of specific experiential and gestalt-derived emotion-focused interventions. Clinical and theoretical implications of these findings are presented.
NASA Astrophysics Data System (ADS)
Wang, Yongjia; Guo, Chenchen; Li, Qingfeng; Le Fèvre, Arnaud; Leifels, Yvonne; Trautmann, Wolfgang
2018-03-01
Background: The nuclear incompressibility (K0) plays a crucial role in understanding diverse phenomena in nuclear structure and reactions, as well as in astrophysics. Heavy-ion-collision measurements in combination with transport model simulations serve as important tools for extracting the nuclear incompressibility. However, uncertainties in transport models (or model dependence) partly affect the reliability of the extracted result. Purpose: In the present work, by using the recently measured data of rapidity-dependent flows, we constrain the incompressibility of nuclear matter and analyze the impact of model uncertainties on the obtained value. Method: The method is based on the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model in which the Skyrme potential energy-density functional is introduced. Three different Skyrme interactions which give different incompressibilities varying from K0 = 201 to 271 MeV are adopted. The incompressibility is deduced from the comparison of the UrQMD model simulations and the FOPI data for rapidity-dependent elliptic flow in Au + Au collisions at beam energies 0.4A-1.0A GeV. Results: The elliptic flow v2 as a function of rapidity y0 can be well described by a quadratic fit v2 =v20 +v22 ṡ y02 . It is found that the quantity v2n defined by v2n = |v20 | + |v22 | is quite sensitive to the incompressibility K0 and the in-medium nucleon-nucleon cross section, but not sensitive to the slope parameter L of the nuclear symmetry energy. Conclusions: With the FU3FP4 parametrization of the in-medium nucleon-nucleon cross section, an averaged K0 = 220 ± 40 MeV is extracted from the v2n of free protons and deuterons. However, remaining systematic uncertainties, partly related to the choice of in-medium nucleon-nucleon cross sections, are of the same magnitude (± 40 MeV). Overall, the rapidity dependent elliptic flow supports a soft symmetric-matter equation-of-state.
Meson exchange current (MEC) models in neutrino interaction generators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Katori, Teppei
2015-05-15
Understanding of the so-called 2 particle-2 hole (2p-2h) effect is an urgent program in neutrino interaction physics for current and future oscillation experiments. Such processes are believed to be responsible for the event excesses observed by recent neutrino experiments. The 2p-2h effect is dominated by the meson exchange current (MEC), and is accompanied by a 2-nucleon emission from the primary vertex, instead of a single nucleon emission from the charged-current quasi-elastic (CCQE) interaction. Current and future high resolution experiments can potentially nail down this effect. For this reason, there are world wide efforts to model and implement this process inmore » neutrino interaction simulations. In these proceedings, I would like to describe how this channel is modeled in neutrino interaction generators.« less
Absolute Navigation Performance of the Orion Exploration Fight Test 1
NASA Technical Reports Server (NTRS)
Zanetti, Renato; Holt, Greg; Gay, Robert; D'Souza, Christopher; Sud, Jastesh
2016-01-01
Launched in December 2014 atop a Delta IV Heavy from the Kennedy Space Center, the Orion vehicle's Exploration Flight Test-1 (EFT-1) successfully completed the objective to stress the system by placing the un-crewed vehicle on a high-energy parabolic trajectory replicating conditions similar to those that would be experienced when returning from an asteroid or a lunar mission. Unique challenges associated with designing the navigation system for EFT-1 are presented with an emphasis on how redundancy and robustness influenced the architecture. Two Inertial Measurement Units (IMUs), one GPS receiver and three barometric altimeters (BALTs) comprise the navigation sensor suite. The sensor data is multiplexed using conventional integration techniques and the state estimate is refined by the GPS pseudorange and deltarange measurements in an Extended Kalman Filter (EKF) that employs UDU factorization. The performance of the navigation system during flight is presented to substantiate the design.
{rho}-{omega} mixing and spin dependent charge-symmetry violating potential
DOE Office of Scientific and Technical Information (OSTI.GOV)
Biswas, Subhrajyoti; Roy, Pradip; Dutt-Mazumder, Abhee K.
2008-10-15
We construct the charge symmetry violating (CSV) nucleon-nucleon potential induced by the {rho}{sup 0}-{omega} mixing due to the neutron-proton mass difference driven by the NN loop. Analytical expression for the two-body CSV potential is presented containing both the central and noncentral NN interaction. We show that the {rho}NN tensor interaction can significantly enhance the charge symmetry violating NN interaction even if the momentum dependent off-shell {rho}{sup 0}-{omega} mixing amplitude is considered. It is also shown that the inclusion of form factors removes the divergence arising out of the contact interaction. Consequently, we see that the precise size of the computedmore » scattering length difference depends on how the short-range aspects of the CSV potential are treated.« less
Isospin flip as a relativistic effect: NN interactions
NASA Technical Reports Server (NTRS)
Buck, W. W.
1993-01-01
Results are presented of an analytic relativistic calculation of a OBE nucleon-nucleon (NN) interaction employing the Gross equation. The calculation consists of a non-relativistic reduction that keeps the negative energy states. The result is compared to purely non-relativistic OBEP results and the relativistic effects are separated out. One finds that the resulting relativistic effects are expressable as a power series in (tau(sub 1))(tau(sub 2)) that agrees, qualitatively, with NN scattering. Upon G-parity transforming this NN potential, one obtains, qualitatively, a short range NN spectroscopy in which the S-states are the lowest states.
Photonuclear sum rules and the tetrahedral configuration of He4
NASA Astrophysics Data System (ADS)
Gazit, Doron; Barnea, Nir; Bacca, Sonia; Leidemann, Winfried; Orlandini, Giuseppina
2006-12-01
Three well-known photonuclear sum rules (SR), i.e., the Thomas-Reiche-Kuhn, the bremsstrahlungs and the polarizability SR are calculated for He4 with the realistic nucleon-nucleon potential Argonne V18 and the three-nucleon force Urbana IX. The relation between these sum rules and the corresponding energy weighted integrals of the cross section is discussed. Two additional equivalences for the bremsstrahlungs SR are given, which connect it to the proton-neutron and neutron-neutron distances. Using them, together with our result for the bremsstrahlungs SR, we find a deviation from the tetrahedral symmetry of the spatial configuration of He4. The possibility to access this deviation experimentally is discussed.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-28
... DEPARTMENT OF THE TREASURY Fiscal Service Financial Management Service; Proposed Collection of Information: Electronic Funds Transfer (EFT) Market Research Study AGENCY: Financial Management Service, Fiscal Service, Treasury. ACTION: Notice and Request for comments. SUMMARY: The Financial Management...
Dark Matter characterization at the LHC in the Effective Field Theory approach
NASA Astrophysics Data System (ADS)
Belyaev, Alexander; Panizzi, Luca; Pukhov, Alexander; Thomas, Marc
2017-04-01
We have studied the complete set of dimension 5 and dimension 6 effective operators involving the interaction of scalar, fermion and vector Dark Matter (DM) with SM quarks and gluons, to explore the possibility to distinguish these operators and characterise the spin of DM at the LHC. We have found that three factors — the effective dimension of the operator, the structure of the SM part of the operator and the parton densities of the SM particles connected to the operator — uniquely define the shape of the (unobservable) invariant mass distribution of the DM pair and, consequently, the shape of the (observable) E T miss distribution related to it. Using χ2 analysis, we found that at the LHC, with a luminosity of 300 fb-1, certain classes of EFT operators can be distinguished from each other. Hence, since DM spin is partly correlated with the factors defining the shape of E T miss , the LHC can potentially shed a light also on DM spin. We have also observed a drastic difference in the efficiencies (up to two orders of magnitude) for large E T miss cuts scenarios with different DM spin, thus indicating that the DM discovery potential strongly depends on it. The study we perform here can be applied more generally than within the EFT paradigm, where the DM mediator is not produced on-the-mass-shell, such as the case of t-channel mediator or mediator with mass below 2 M DM, where the invariant mass of the DM pair is not fixed.
MAEDA, Shuji; AKAISHI, Yoshinori; YAMAZAKI, Toshimitsu
2013-01-01
Non-relativistic Faddeev and Faddeev-Yakubovsky calculations were made for K−pp, K−ppn, K−K−p and K−K−pp kaonic nuclear clusters, where the quasi bound states were treated as bound states by employing real separable potential models for the K−-K− and the K−-nucleon interactions as well as for the nucleon-nucleon interaction. The binding energies and spatial shrinkages of these states, obtained for various values of the interaction, were found to increase rapidly with the interaction strength. Their behaviors are shown in a reference diagram, where possible changes by varying the interaction in the dense nuclear medium are given. Using the Λ(1405) ansatz with a PDG mass of 1405 MeV/c2 for K−p, the following ground-state binding energies together with the wave functions were obtained: 51.5 MeV (K−pp), 69 MeV (K−ppn), 30.4 MeV (K−K−p) and 93 MeV (K−K−pp), which are in good agreement with previous results of variational calculation based on the Akaishi-Yamazaki coupled-channel potential. The K−K−pp state has a significantly increased density where the two nucleons are located very close to each other, in spite of the inner NN repulsion. Relativistic corrections on the calculated non-relativistic results indicate substantial lowering of the bound-state masses, especially of K−K−pp, toward the kaon condensation regime. The fact that the recently observed binding energy of K−pp is much larger (by a factor of 2) than the originally predicted one may infer an enhancement of the interaction in dense nuclei by about 25% possibly due to chiral symmetry restoration. In this respect some qualitative accounts are given based on “clearing QCD vacuum” model of Brown, Kubodera and Rho. PMID:24213206
Chiral perturbation theory and nucleon-pion-state contaminations in lattice QCD
NASA Astrophysics Data System (ADS)
Bär, Oliver
2017-05-01
Multiparticle states with additional pions are expected to be a non-negligible source of excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory can be employed to calculate the contamination due to two-particle nucleon-pion-states in various nucleon observables. Leading order results are presented for the nucleon axial, tensor and scalar charge and three Mellin moments of parton distribution functions (quark momentum fraction, helicity and transversity moment). Taking into account phenomenological results for the charges and moments the impact of the nucleon-pion-states on lattice estimates for these observables can be estimated. The nucleon-pion-state contribution results in an overestimation of all charges and moments obtained with the plateau method. The overestimation is at the 5-10% level for source-sink separations of about 2 fm. The source-sink separations accessible in contemporary lattice simulations are found to be too small for chiral perturbation theory to be directly applicable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lonardoni, D.; Gandolfi, S.; Lynn, J. E.
Quantum Monte Carlo methods have recently been employed to study properties of nuclei and infinite matter using local chiral effective-field-theory interactions. In this paper, we present a detailed description of the auxiliary field diffusion Monte Carlo algorithm for nuclei in combination with local chiral two- and three-nucleon interactions up to next-to-next-to-leading order. We show results for the binding energy, charge radius, charge form factor, and Coulomb sum rule in nuclei withmore » $$3{\\le}A{\\le}16$$. Particular attention is devoted to the effect of different operator structures in the three-body force for different cutoffs. Finally, the outcomes suggest that local chiral interactions fit to few-body observables give a very good description of the ground-state properties of nuclei up to $$^{16}\\mathrm{O}$$, with the exception of one fit for the softer cutoff which predicts overbinding in larger nuclei.« less
Lonardoni, D.; Gandolfi, S.; Lynn, J. E.; ...
2018-04-24
Quantum Monte Carlo methods have recently been employed to study properties of nuclei and infinite matter using local chiral effective-field-theory interactions. In this paper, we present a detailed description of the auxiliary field diffusion Monte Carlo algorithm for nuclei in combination with local chiral two- and three-nucleon interactions up to next-to-next-to-leading order. We show results for the binding energy, charge radius, charge form factor, and Coulomb sum rule in nuclei withmore » $$3{\\le}A{\\le}16$$. Particular attention is devoted to the effect of different operator structures in the three-body force for different cutoffs. Finally, the outcomes suggest that local chiral interactions fit to few-body observables give a very good description of the ground-state properties of nuclei up to $$^{16}\\mathrm{O}$$, with the exception of one fit for the softer cutoff which predicts overbinding in larger nuclei.« less
Measurement of interaction between antiprotons
Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; ...
2015-11-04
In this paper, one of the primary goals of nuclear physics is to understand the force between nucleons, which is a necessary step for understanding the structure of nuclei and how nuclei interact with each other. Rutherford discovered the atomic nucleus in 1911, and the large body of knowledge about the nuclear force that has since been acquired was derived from studies made on nucleons or nuclei. Although antinuclei up to antihelium-4 have been discovered and their masses measured, little is known directly about the nuclear force between antinucleons. Here, we study antiproton pair correlations among data collected by themore » STAR experiment at the Relativistic Heavy Ion Collider (RHIC), where gold ions are collided with a centre-of-mass energy of 200 gigaelectronvolts per nucleon pair. Antiprotons are abundantly produced in such collisions, thus making it feasible to study details of the antiproton–antiproton interaction. By applying a technique similar to Hanbury Brown and Twiss intensity interferometry, we show that the force between two antiprotons is attractive. In addition, we report two key parameters that characterize the corresponding strong interaction: the scattering length and the effective range of the interaction. Our measured parameters are consistent within errors with the corresponding values for proton–proton interactions. Our results provide direct information on the interaction between two antiprotons, one of the simplest systems of antinucleons, and so are fundamental to understanding the structure of more-complex antinuclei and their properties.« less
Ozdil, Kamil; Caliskan, Zuhal; Keles, Nursen; Ozturk, Oguzhan; Tekin, Ahmet Selami; Kahraman, Resul; Doganay, Levent; Demircioglu, Kenan; Yilmaz, Yusuf; Caliskan, Mustafa
2017-01-01
OBJECTIVE: Inflammatory bowel diseases (IBD) consist of a number of chronic inflammatory diseases. Inflammatory process is known to be involved in all stages of atherosclerosis. Early atherosclerosis is reflected by increased levels of carotid artery intima media thickness (c-IMT) and high-sensitivity C-reactive protein (hs-CRP). Epicardial fat thickness (EFT) strongly influences both the formation and progression of atherosclerosis. Recent studies have demonstrated a relationship between c-IMT and hs-CRP levels and the risk of atherosclerosis in patients with IBD. However, no study has yet compared EFT between patients with IBD and the general healthy population. Hence, this study was designed to further evaluate whether patients with IBD have higher EFT values with increased c-IMT and hs-CRP levels compared to those in the healthy population. METHODS: A total of 110 patients with IBD and 105 healthy volunteers were enrolled into this study. EFT was evaluated by transthoracic echocardiography. c-IMT levels were measured using an ultrasound scanner with a linear probe. The plasma levels of hs-CRP were measured using a highly sensitive sandwich ELISA technique. RESULTS: The hs-CRP and c-IMT levels of patients with IBD were significantly higher than those of the control group. The EFT values of patients with IBD were significantly higher than those of the control group (0.54±0.13 vs. 0.49±0.09, p=0.002). CONCLUSION: Echocardiographic EFT measurements of patients with IBD were significantly higher than those of the normal population, which may be associated with an increased subclinical atherosclerosis risk in these patients. PMID:28752137
Isospin splitting of nucleon effective mass and symmetry energy in isotopic nuclear reactions
NASA Astrophysics Data System (ADS)
Guo, Ya-Fei; Chen, Peng-Hui; Niu, Fei; Zhang, Hong-Fei; Jin, Gen-Ming; Feng, Zhao-Qing
2017-10-01
Within an isospin and momentum dependent transport model, the dynamics of isospin particles (nucleons and light clusters) in Fermi-energy heavy-ion collisions are investigated for constraining the isospin splitting of nucleon effective mass and the symmetry energy at subsaturation densities. The impacts of the isoscalar and isovector parts of the momentum dependent interaction on the emissions of isospin particles are explored, i.e., the mass splittings of and (). The single and double neutron to proton ratios of free nucleons and light particles are thoroughly investigated in the isotopic nuclear reactions of 112Sn+112Sn and 124Sn+124Sn at incident energies of 50 and 120 MeV/nucleon, respectively. It is found that both the effective mass splitting and symmetry energy impact the kinetic energy spectra of the single ratios, in particular at the high energy tail (larger than 20 MeV). The isospin splitting of nucleon effective mass slightly impacts the double ratio spectra at the energy of 50 MeV/nucleon. A soft symmetry energy with stiffness coefficient of γ s=0.5 is constrained from the experimental data with the Fermi-energy heavy-ion collisions. Supported by Major State Basic Research Development Program in China (2014CB845405, 2015CB856903), National Natural Science Foundation of China (11722546, 11675226, 11675066, U1332207) and Youth Innovation Promotion Association of Chinese Academy of Sciences
NASA Astrophysics Data System (ADS)
Abe, K.; Andreopoulos, C.; Antonova, M.; Aoki, S.; Ariga, A.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bartet-Friburg, P.; Batkiewicz, M.; Berardi, V.; Berkman, S.; Bhadra, S.; Blondel, A.; Bolognesi, S.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buizza Avanzini, M.; Calland, R. G.; Cao, S.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Chikuma, N.; Christodoulou, G.; Clifton, A.; Coleman, J.; Collazuol, G.; Cremonesi, L.; Dabrowska, A.; De Rosa, G.; Dealtry, T.; Denner, P. F.; Dennis, S. R.; Densham, C.; Dewhurst, D.; Di Lodovico, F.; Di Luise, S.; Dolan, S.; Drapier, O.; Duffy, K. E.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery-Schrenk, S.; Ereditato, A.; Feusels, T.; Finch, A. J.; Fiorentini, G. A.; Friend, M.; Fujii, Y.; Fukuda, D.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Garcia, A.; Giffin, S. G.; Giganti, C.; Gizzarelli, F.; Gonin, M.; Grant, N.; Hadley, D. R.; Haegel, L.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayashino, T.; Hayato, Y.; Helmer, R. L.; Hierholzer, M.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Hogan, M.; Holeczek, J.; Horikawa, S.; Hosomi, F.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ikeda, M.; Imber, J.; Insler, J.; Intonti, R. A.; Irvine, T. J.; Ishida, T.; Ishii, T.; Iwai, E.; Iwamoto, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Jiang, M.; Johnson, S.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Karlen, D.; Karpikov, I.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kim, H.; Kim, J.; King, S.; Kisiel, J.; Knight, A.; Knox, A.; Kobayashi, T.; Koch, L.; Koga, T.; Konaka, A.; Kondo, K.; Kopylov, A.; Kormos, L. L.; Korzenev, A.; Koshio, Y.; Kropp, W.; Kudenko, Y.; Kurjata, R.; Kutter, T.; Lagoda, J.; Lamont, I.; Larkin, E.; Lasorak, P.; Laveder, M.; Lawe, M.; Lazos, M.; Lindner, T.; Liptak, Z. J.; Litchfield, R. P.; Li, X.; Longhin, A.; Lopez, J. P.; Ludovici, L.; Lu, X.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Martins, P.; Martynenko, S.; Maruyama, T.; Matveev, V.; Mavrokoridis, K.; Ma, W. Y.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Mefodiev, A.; Mezzetto, M.; Mijakowski, P.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Moriyama, S.; Mueller, Th. A.; Murphy, S.; Myslik, J.; Nakadaira, T.; Nakahata, M.; Nakamura, K. G.; Nakamura, K.; Nakamura, K. D.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nantais, C.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; Nowak, J.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Ovsyannikova, T.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Patel, N. D.; Pavin, M.; Payne, D.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pickering, L.; Pinzon Guerra, E. S.; Pistillo, C.; Popov, B.; Posiadala-Zezula, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reinherz-Aronis, E.; Riccio, C.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Rychter, A.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shah, R.; Shaikhiev, A.; Shaker, F.; Shaw, D.; Shiozawa, M.; Shirahige, T.; Short, S.; Smy, M.; Sobczyk, J. T.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Stewart, T.; Suda, Y.; Suvorov, S.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Terhorst, D.; Terri, R.; Thakore, T.; Thompson, L. F.; Tobayama, S.; Toki, W.; Tomura, T.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Vacheret, A.; Vagins, M.; Vallari, Z.; Vasseur, G.; Wachala, T.; Wakamatsu, K.; Walter, C. W.; Wark, D.; Warzycha, W.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Wilson, J. R.; Wilson, R. J.; Yamada, Y.; Yamamoto, K.; Yamamoto, M.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yoshida, K.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration
2016-06-01
We report the measurement of muon neutrino charged-current interactions on carbon without pions in the final state at the T2K beam energy using 5.734 ×1020 protons on target. For the first time the measurement is reported as a flux-integrated, double-differential cross section in muon kinematic variables (cos θμ, pμ), without correcting for events where a pion is produced and then absorbed by final state interactions. Two analyses are performed with different selections, background evaluations and cross-section extraction methods to demonstrate the robustness of the results against biases due to model-dependent assumptions. The measurements compare favorably with recent models which include nucleon-nucleon correlations but, given the present precision, the measurement does not distinguish among the available models. The data also agree with Monte Carlo simulations which use effective parameters that are tuned to external data to describe the nuclear effects. The total cross section in the full phase space is σ =(0.417 ±0.047 (syst ) ±0.005 (stat ) )×10-38 cm2 nucleon-1 and the cross section integrated in the region of phase space with largest efficiency and best signal-over-background ratio (cos θμ>0.6 and pμ>200 MeV ) is σ =(0.202 ±0.036 (syst ) ±0.003 (stat ) )×10-38 cm2 nucleon-1 .
Multinucleon pion absorption in the sup 4 He(. pi. sup + , ppp ) n reaction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weber, P.; McAlister, J.; Olszewski, R.
1991-04-01
Three-proton emission cross sections for the {sup 4}He({pi}{sup +},{ital ppp}){ital n} reaction were measured at an incident pion kinetic energy of {ital T}{sub {pi}}{sup +}=165 MeV over a wide angular range in a kinematically complete experiment. Angular correlations, missing momentum distributions, and energy spectra are compared with three- and four-body phase-space Monte Carlo calculations. The results provide strong evidence that most of the three-proton coincidences result from three-nucleon absorption. From phase-space integration the total three-nucleon absorption cross section is estimated to be {sigma}{sup 3{ital N}}=4.8{plus minus}1.0 mb. The cross section involving four nucleons is small and is estimated to bemore » {sigma}{sup 4{ital N}}{lt}2 mb. On the scale of the total absorption cross section in {sup 4}He, multinucleon pion absorption seems to represent only a small fraction.« less
Investigation of the Three-Nucleon System Dynamics in the Deuteron-Proton Breakup Reaction
NASA Astrophysics Data System (ADS)
Ciepał, I.; Kłos, B.; Kistryn, St.; Stephan, E.; Biegun, A.; Bodek, K.; Deltuva, A.; Epelbaum, E.; Eslami-Kalantari, M.; Fonseca, A. C.; Golak, J.; Jha, V.; Kalantar-Nayestanaki, N.; Kamada, H.; Khatri, G.; Kirillov, Da.; Kirillov, Di.; Kliczewski, St.; Kozela, A.; Kravcikova, M.; Machner, H.; Magiera, A.; Martinska, G.; Messchendorp, J.; Nogga, A.; Parol, W.; Ramazani-Moghaddam-Arani, A.; Roy, B. J.; Sakai, H.; Sekiguchi, K.; Sitnik, I.; Siudak, R.; Skibiński, R.; Sworst, R.; Urban, J.; Witała, H.; Zejma, J.
2014-08-01
Precise and large sets of cross section, vector A x , A y and tensor A xx , A xy , A yy analyzing power data for the 1 H( d, pp) n breakup reactions were measured at 100 and 130 MeV deuteron beam energies with the SALAD and BINA detectors at KVI and the Germanium Wall setup at FZ-Jülich. Results are compared with various theoretical approaches which model the three-nucleon system dynamics. The cross section data reveal a sizable three-nucleon force (3NF) and Coulomb force influence. In case of the analyzing powers very low sensitivity to these effects was found and the data are well describe by 2N models only. For A xy at 130 MeV, serious disagreements were observed when 3NF models are included in the calculations.
Emotional Freedom Techniques for Anxiety: A Systematic Review With Meta-analysis.
Clond, Morgan
2016-05-01
Emotional Freedom Technique (EFT) combines elements of exposure and cognitive therapies with acupressure for the treatment of psychological distress. Randomized controlled trials retrieved by literature search were assessed for quality using the criteria developed by the American Psychological Association's Division 12 Task Force on Empirically Validated Treatments. As of December 2015, 14 studies (n = 658) met inclusion criteria. Results were analyzed using an inverse variance weighted meta-analysis. The pre-post effect size for the EFT treatment group was 1.23 (95% confidence interval, 0.82-1.64; p < 0.001), whereas the effect size for combined controls was 0.41 (95% confidence interval, 0.17-0.67; p = 0.001). Emotional freedom technique treatment demonstrated a significant decrease in anxiety scores, even when accounting for the effect size of control treatment. However, there were too few data available comparing EFT to standard-of-care treatments such as cognitive behavioral therapy, and further research is needed to establish the relative efficacy of EFT to established protocols.
The trispectrum in the Effective Field Theory of Large Scale Structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bertolini, Daniele; Schutz, Katelin; Solon, Mikhail P.
2016-06-01
We compute the connected four point correlation function (the trispectrum in Fourier space) of cosmological density perturbations at one-loop order in Standard Perturbation Theory (SPT) and the Effective Field Theory of Large Scale Structure (EFT of LSS). This paper is a companion to our earlier work on the non-Gaussian covariance of the matter power spectrum, which corresponds to a particular wavenumber configuration of the trispectrum. In the present calculation, we highlight and clarify some of the subtle aspects of the EFT framework that arise at third order in perturbation theory for general wavenumber configurations of the trispectrum. We consistently incorporatemore » vorticity and non-locality in time into the EFT counterterms and lay out a complete basis of building blocks for the stress tensor. We show predictions for the one-loop SPT trispectrum and the EFT contributions, focusing on configurations which have particular relevance for using LSS to constrain primordial non-Gaussianity.« less
Coarsening behavior of γ' and γ″ phases in GH4169 superalloy by electric field treatment
NASA Astrophysics Data System (ADS)
Wang, Lei; Wang, Yao; Liu, Yang; Song, Xiu; Lü, Xu-dong; Zhang, Bei-jiang
2013-09-01
The coarsening behaviors of γ' and γ″ phases in GH4169 alloy aged at 1023 and 1073 K with electric field treatment (EFT) were investigated by transmission electron microscopy (TEM) and positron annihilation lifetime spectroscopy (PALS). It is demonstrated that precipitation coarsening occurs, and the growth activation energies of γ' and γ″ phases can be decreased to 115.6 and 198.1 kJ·mol-1, respectively, by applying the electric field. The formation of a large number of vacancies in the matrix is induced by EFT. Due to the occurrence of vacancy migration, the diffusion coefficients of Al and Nb atoms are increased to be 1.6-5.0 times larger than those without EFT at 1023 or 1073 K. Furthermore, the formation of vacancy clusters is promoted by EFT, and the increase in strain energy for the coarsening of γ' and γ″ phases can be counterbalanced by the formation of vacancy clusters.
Two-nucleon emitters within a pseudostate method: The case of 6Be and 16Be
NASA Astrophysics Data System (ADS)
Casal, J.
2018-03-01
Background: Since the first experimental observation, two-nucleon radioactivity has gained renewed attention since the early 2000s. The 6Be system is the lightest two-proton ground-state emitter, while 16Be was recently proposed to be the first two-neutron ground-state emitter ever observed. A proper understanding of their properties and decay modes requires a reasonable description of the three-body continuum. Purpose: Study the ground-state properties of 6Be and 16Be within a general three-body model and investigate their nucleon-nucleon correlations in the continuum. Method: The pseudostate (PS) method in hyperspherical coordinates, using the analytical transformed harmonic oscillator (THO) basis for three-body systems, is used to construct the 6Be and 16Be ground-state wave functions. These resonances are approximated as a stable PS around the known two-nucleon separation energy. Effective core-N potentials, constrained by the available experimental information on the binary subsystems 5Li and 15Be, are employed in the calculations. Results: The ground state of 16Be is found to present a strong dineutron configuration, with the valence neutrons occupying mostly an l =2 state relative to the core. The results are consistent with previous R -matrix calculations for the actual continuum. The case of 6Be shows a clear symmetry with respect to its mirror partner, the two-neutron halo 6He: The diproton configuration is dominant, and the valence protons occupy an l =1 orbit. Conclusions: The PS method is found to be a suitable tool in describing the properties of unbound core+N +N ground states. For both 16Be and 6Be, the results are consistent with previous theoretical studies and confirm the dominant dinucleon configuration. This favors the picture of a correlated two-nucleon emission.
Proton Distribution Radii of 12-19C Illuminate Features of Neutron Halos
Kanungo, R.; Horiuchi, W.; Hagen, Gaute; ...
2016-09-02
We report proton radii of 12-19C densities derived from first accurate charge changing cross section measurements at 900A MeV with a carbon target. A thick neutron surface evolves from ~0.5 fm in 15C to ~1 fm in 19C. Also, the halo radius in 19C is found to be 6.4±0.7 fm as large as 11Li. Ab initio calculations based on chiral nucleon-nucleon and three-nucleon forces reproduce the radii well.
EFT-1 Crew Module on Display at KSC Visitor Complex
2017-04-12
The Orion crew module from Exploration Flight Test 1 (EFT-1) is on display at nearby NASA Kennedy Space Center Visitor Complex in Florida. The crew module is part of the NASA Now exhibit in the IMAX Theater. Also in view is a scale model of NASA's Space Launch System rocket and Orion spacecraft on the mobile launcher. The Orion EFT-1 spacecraft launched atop a United Launch Alliance Delta IV rocket Dec. 5, 2014, from Space Launch Complex 37 at Cape Canaveral Air Force Station. The spacecraft built for humans traveled 3,604 miles above Earth and splashed down about 4.5 hours later in the Pacific Ocean.
The bound-state properties summary and recommendations of working group 1
NASA Astrophysics Data System (ADS)
Friar, J. L.; Frois, B.
A dozen years ago virtually nothing was known about three-nucleon forces. In the intervening years we have learned to solve routinely the trinucleon bound-state Faddeev equations for what amounts to the complete (model) nucleon-nucleon potential, and to include complicated three-nucleon forces as well. The art of constructing those forces has dramatically improved, and modern versions of these forces contain components derived from the exchange of heavy mesons, in addition to pion exchange. Experimental sophistication in probing the trinucleon ground states has made similar improvements. The recent Saclay and MIT tritium form factor experiments have finally unravelled the isospin structure of the trinucleon charge densities, and have generated new challenges for theorists. Although there are few definite conclusions yet and much remains to be done, the progress has been exceptional. Perhaps it is not too pretentious to quote the final frame of the movie 41 Destination Moon: "This is the end of the beginning."
Are there any narrow K--nuclear states?
NASA Astrophysics Data System (ADS)
Hrtánková, Jaroslava; Mareš, Jiří
2017-07-01
We performed self-consistent calculations of K--nuclear quasi-bound states using a single-nucleon K- optical potential derived from chiral meson-baryon coupled-channel interaction models, supplemented by a phenomenological K- multinucleon potential introduced recently to achieve good fits to kaonic atom data [1]. Our calculations show that the effect of K- multinucleon interactions on K- widths in nuclei is decisive. The resulting widths are considerably larger than corresponding binding energies. Moreover, when the density dependence of the K--multinucleon interactions derived in the fits of kaonic atoms is extended to the nuclear interior, the only two models acceptable after imposing as additional constraint the single-nucleon fraction of K- absorption at rest do not yield any kaonic nuclear bound state in majority of considered nuclei.
Cluster correlation and fragment emission in 12C+12C at 95 MeV/nucleon
NASA Astrophysics Data System (ADS)
Tian, G.; Chen, Z.; Han, R.; Shi, F.; Luo, F.; Sun, Q.; Song, L.; Zhang, X.; Xiao, G. Q.; Wada, R.; Ono, A.
2018-03-01
The impact of cluster correlations has been studied in the intermediate mass fragment (IMF) emission in 12C+12C at 95 MeV/nucleon, using antisymmetrized molecular dynamics (AMD) model simulations. In AMD, the cluster correlation is introduced as a process to form light clusters with A ≤4 in the final states of a collision induced by the nucleon-nucleon residual interaction. Correlations between light clusters are also considered to form light nuclei with A ≤9 . This version of AMD, combined with GEMINI to calculate the decay of primary fragments, reproduces the experimental energy spectra of IMFs well overall with reasonable reproduction of light charged particles when we carefully analyze the excitation energies of primary fragments produced by AMD and their secondary decays. The results indicate that the cluster correlation plays a crucial role for producing fragments at relatively low excitation energies in the intermediate-energy heavy-ion collisions.
Lattice calculation of electric dipole moments and form factors of the nucleon
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abramczyk, M.; Aoki, S.; Blum, T.
In this paper, we analyze commonly used expressions for computing the nucleon electric dipole form factors (EDFF)more » $$F_3$$ and moments (EDM) on a lattice and find that they lead to spurious contributions from the Pauli form factor $$F_2$$ due to inadequate definition of these form factors when parity mixing of lattice nucleon fields is involved. Using chirally symmetric domain wall fermions, we calculate the proton and the neutron EDFF induced by the CP-violating quark chromo-EDM interaction using the corrected expression. In addition, we calculate the electric dipole moment of the neutron using a background electric field that respects time translation invariance and boundary conditions, and we find that it decidedly agrees with the new formula but not the old formula for $$F_3$$. In conclusion, we analyze some selected lattice results for the nucleon EDM and observe that after the correction is applied, they either agree with zero or are substantially reduced in magnitude, thus reconciling their difference from phenomenological estimates of the nucleon EDM.« less
Lattice calculation of electric dipole moments and form factors of the nucleon
Abramczyk, M.; Aoki, S.; Blum, T.; ...
2017-07-10
In this paper, we analyze commonly used expressions for computing the nucleon electric dipole form factors (EDFF)more » $$F_3$$ and moments (EDM) on a lattice and find that they lead to spurious contributions from the Pauli form factor $$F_2$$ due to inadequate definition of these form factors when parity mixing of lattice nucleon fields is involved. Using chirally symmetric domain wall fermions, we calculate the proton and the neutron EDFF induced by the CP-violating quark chromo-EDM interaction using the corrected expression. In addition, we calculate the electric dipole moment of the neutron using a background electric field that respects time translation invariance and boundary conditions, and we find that it decidedly agrees with the new formula but not the old formula for $$F_3$$. In conclusion, we analyze some selected lattice results for the nucleon EDM and observe that after the correction is applied, they either agree with zero or are substantially reduced in magnitude, thus reconciling their difference from phenomenological estimates of the nucleon EDM.« less
Lattice QCD spectroscopy for hadronic CP violation
DOE Office of Scientific and Technical Information (OSTI.GOV)
de Vries, Jordy; Mereghetti, Emanuele; Seng, Chien -Yeah
Here, the interpretation of nuclear electric dipole moment (EDM) experiments is clouded by large theoretical uncertainties associated with nonperturbative matrix elements. In various beyond-the-Standard Model scenarios nuclear and diamagnetic atomic EDMs are expected to be dominated by CP-violating pion–nucleon interactions that arise from quark chromo-electric dipole moments. The corresponding CP-violating pion–nucleon coupling strengths are, however, poorly known. In this work we propose a strategy to calculate these couplings by using spectroscopic lattice QCD techniques. Instead of directly calculating the pion–nucleon coupling constants, a challenging task, we use chiral symmetry relations that link the pion–nucleon couplings to nucleon sigma terms andmore » mass splittings that are significantly easier to calculate. In this work, we show that these relations are reliable up to next-to-next-to-leading order in the chiral expansion in both SU(2) and SU(3) chiral perturbation theory. We conclude with a brief discussion about practical details regarding the required lattice QCD calculations and the phenomenological impact of an improved understanding of CP-violating matrix elements.« less
Lattice QCD spectroscopy for hadronic CP violation
de Vries, Jordy; Mereghetti, Emanuele; Seng, Chien -Yeah; ...
2017-01-16
Here, the interpretation of nuclear electric dipole moment (EDM) experiments is clouded by large theoretical uncertainties associated with nonperturbative matrix elements. In various beyond-the-Standard Model scenarios nuclear and diamagnetic atomic EDMs are expected to be dominated by CP-violating pion–nucleon interactions that arise from quark chromo-electric dipole moments. The corresponding CP-violating pion–nucleon coupling strengths are, however, poorly known. In this work we propose a strategy to calculate these couplings by using spectroscopic lattice QCD techniques. Instead of directly calculating the pion–nucleon coupling constants, a challenging task, we use chiral symmetry relations that link the pion–nucleon couplings to nucleon sigma terms andmore » mass splittings that are significantly easier to calculate. In this work, we show that these relations are reliable up to next-to-next-to-leading order in the chiral expansion in both SU(2) and SU(3) chiral perturbation theory. We conclude with a brief discussion about practical details regarding the required lattice QCD calculations and the phenomenological impact of an improved understanding of CP-violating matrix elements.« less
Polarization observables in few nucleon systems with CLAS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zachariou, Nicholas
The CEBAF Large Acceptance Spectrometer (CLAS), housed in Hall-B at the Thomas Jefferson National Accelerator Facility provides us with the experimental tools to study strongly-interacting matter and its dynamics in the transition from hadronic to partonic degrees of freedom in nuclear interactions. In this paper we discuss the progress made in understanding the relevant degrees of freedom using polarisation observables of deuteron photodisintegration in the few-GeV photon-energy region. We also address progress made in studying the interaction between Hyperons and Nucleons via polarisation observables, utilising high-statistics experiments that provided us with the large data samples needed to study final-state interactions,more » as well as perform detailed studies on initial-state effects. The polarisation observables presented here provide us with unique experimental tools to study the underlying dynamics of both initial and final-state interactions, as well as the information needed to disentangle signal from background contributions.« less
Polarization observables in few nucleon systems with CLAS
Zachariou, Nicholas
2017-12-01
The CEBAF Large Acceptance Spectrometer (CLAS), housed in Hall-B at the Thomas Jefferson National Accelerator Facility provides us with the experimental tools to study strongly-interacting matter and its dynamics in the transition from hadronic to partonic degrees of freedom in nuclear interactions. In this paper we discuss the progress made in understanding the relevant degrees of freedom using polarisation observables of deuteron photodisintegration in the few-GeV photon-energy region. We also address progress made in studying the interaction between Hyperons and Nucleons via polarisation observables, utilising high-statistics experiments that provided us with the large data samples needed to study final-state interactions,more » as well as perform detailed studies on initial-state effects. The polarisation observables presented here provide us with unique experimental tools to study the underlying dynamics of both initial and final-state interactions, as well as the information needed to disentangle signal from background contributions.« less
West, Michael D.; Labat, Ivan; Sternberg, Hal; Larocca, Dana; Nasonkin, Igor; Chapman, Karen B.; Singh, Ratnesh; Makarev, Eugene; Aliper, Alex; Kazennov, Andrey; Alekseenko, Andrey; Shuvalov, Nikolai; Cheskidova, Evgenia; Alekseev, Aleksandr; Artemov, Artem; Putin, Evgeny; Mamoshina, Polina; Pryanichnikov, Nikita; Larocca, Jacob; Copeland, Karen; Izumchenko, Evgeny; Korzinkin, Mikhail; Zhavoronkov, Alex
2018-01-01
Here we present the application of deep neural network (DNN) ensembles trained on transcriptomic data to identify the novel markers associated with the mammalian embryonic-fetal transition (EFT). Molecular markers of this process could provide important insights into regulatory mechanisms of normal development, epimorphic tissue regeneration and cancer. Subsequent analysis of the most significant genes behind the DNNs classifier on an independent dataset of adult-derived and human embryonic stem cell (hESC)-derived progenitor cell lines led to the identification of COX7A1 gene as a potential EFT marker. COX7A1, encoding a cytochrome C oxidase subunit, was up-regulated in post-EFT murine and human cells including adult stem cells, but was not expressed in pre-EFT pluripotent embryonic stem cells or their in vitro-derived progeny. COX7A1 expression level was observed to be undetectable or low in multiple sarcoma and carcinoma cell lines as compared to normal controls. The knockout of the gene in mice led to a marked glycolytic shift reminiscent of the Warburg effect that occurs in cancer cells. The DNN approach facilitated the elucidation of a potentially new biomarker of cancer and pre-EFT cells, the embryo-onco phenotype, which may potentially be used as a target for controlling the embryonic-fetal transition. PMID:29487692
West, Michael D; Labat, Ivan; Sternberg, Hal; Larocca, Dana; Nasonkin, Igor; Chapman, Karen B; Singh, Ratnesh; Makarev, Eugene; Aliper, Alex; Kazennov, Andrey; Alekseenko, Andrey; Shuvalov, Nikolai; Cheskidova, Evgenia; Alekseev, Aleksandr; Artemov, Artem; Putin, Evgeny; Mamoshina, Polina; Pryanichnikov, Nikita; Larocca, Jacob; Copeland, Karen; Izumchenko, Evgeny; Korzinkin, Mikhail; Zhavoronkov, Alex
2018-01-30
Here we present the application of deep neural network (DNN) ensembles trained on transcriptomic data to identify the novel markers associated with the mammalian embryonic-fetal transition (EFT). Molecular markers of this process could provide important insights into regulatory mechanisms of normal development, epimorphic tissue regeneration and cancer. Subsequent analysis of the most significant genes behind the DNNs classifier on an independent dataset of adult-derived and human embryonic stem cell (hESC)-derived progenitor cell lines led to the identification of COX7A1 gene as a potential EFT marker. COX7A1 , encoding a cytochrome C oxidase subunit, was up-regulated in post-EFT murine and human cells including adult stem cells, but was not expressed in pre-EFT pluripotent embryonic stem cells or their in vitro -derived progeny. COX7A1 expression level was observed to be undetectable or low in multiple sarcoma and carcinoma cell lines as compared to normal controls. The knockout of the gene in mice led to a marked glycolytic shift reminiscent of the Warburg effect that occurs in cancer cells. The DNN approach facilitated the elucidation of a potentially new biomarker of cancer and pre-EFT cells, the embryo-onco phenotype, which may potentially be used as a target for controlling the embryonic-fetal transition.
Episodic future thinking and future-based decision-making in a case of retrograde amnesia.
De Luca, Flavia; Benuzzi, Francesca; Bertossi, Elena; Braghittoni, Davide; di Pellegrino, Giuseppe; Ciaramelli, Elisa
2018-02-01
We investigated episodic future thinking (EFT) and future-based cognition and decision-making in patient SG, who developed a dense retrograde amnesia following hypoxia due to a cardiac arrest. Despite intact general cognitive and executive functioning, SG was unable to remember events from his entire lifetime. He had, however, relatively spared anterograde memory and general semantic knowledge. Voxel-based morphometry detected a reduction of gray matter in the thalamus, cerebellum and fusiform gyrus bilaterally, and, at a reduced threshold, in several regions of the autobiographical memory network, including the hippocampi. We show that SG is unable to imagine personal future events, but can imagine fictitious events not self-relevant and not located in subjective time. Despite severely impaired EFT, SG shows normal attitudes towards the future time, and normal delay discounting rates. These findings suggest that retrieval of autobiographical information from long-term memory is necessary for EFT. However, relatively spared anterograde memory and general semantic knowledge may be sufficient to allow construction of fictitious experiences. As well, EFT is not necessary to drive future-oriented cognition and choice. These findings highlight the relation between autobiographical memory and EFT, and the fractionation of human temporal consciousness. Moreover, they contribute to our understanding of retrograde amnesia as an impairment of memory as well as future thinking. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Chouhan, N. S.; Singh, M. K.; Singh, V.; Pathak, R.
2013-12-01
Interactions of 84Kr36 having kinetic energy around 1 GeV per nucleon with NIKFI BR-2 nuclear emulsion detector's target reveal some of the important features of compound multiplicity. Present article shows that width of compound multiplicity distributions and value of mean compound multiplicity have linear relationship with mass number of the projectile colliding system.
Hyperon production from neutrino-nucleon reaction
Wu, Jia -Jun; Zou, Bing -Song
2015-04-10
The neutrino induced hyperon production processes ν¯ e/μ + p → e +/μ + + π + Λ/Σ may provide a unique clean place for studying low energy πΛ/Σ interaction and hyperon resonances below KN threshold. The production rates for some neutrino induced hyperon production processes are estimated with theoretical models. Lastly, suggestions are made for the study of hyperon production from neutrino–nucleon reaction at present and future neutrino facilities.
A predictive theory for elastic scattering and recoil of protons from 4He
Hupin, Guillaume; Quaglioni, Sofia; Navratil, Petr
2014-12-08
Low-energy cross sections for elastic scattering and recoil of protons from 4He nuclei (also known as α particles) are calculated directly by solving the Schrodinger equation for five nucleons interacting through accurate two- and three-nucleon forces derived within the framework of chiral effective field theory. Precise knowledge of these processes at various proton backscattering/recoil angles and energies is needed for the ion-beam analysis of numerous materials, from the surface layers of solids, to thin films, to fusion-reactor materials. Indeed, the same elastic scattering process, in two different kinematic configurations, can be used to probe the concentrations and depth profiles ofmore » either hydrogen or helium. Furthermore, we compare our results to available experimental data and show that direct calculations with modern nuclear potentials can help to resolve remaining inconsistencies among data sets and can be used to predict these cross sections when measurements are not available.« less
Quantum molecular dynamics a microscopic model from UNILAC to CERN energies
NASA Astrophysics Data System (ADS)
Hartnack, C.; Zhuxia, Li; Neise, L.; Peilert, G.; Rosenhauer, A.; Sorge, H.; Aichelin, J.; Stöcker, H.; Greiner, W.
1989-04-01
We demonstrate that the microscopic QMD approach is useful to study heavy ion collisions from fusion fussion phenomena to the quest for signals of the quark gluon plasma. We discuss the possibilities and difficulties to determine the nuclear equation of state from heavy ion collisions. We investigate the influence of momentum dependent interactions and of in medium corrections to the nucleon-nucleon cross sections in the framework of the QMD model. The model is extended to low energies by including a Pauli potential in the nucleon-nucleon interaction. We show that it is possible to extract information on the effective cross sections from the experimental rapidity distributions of the fragments. We also investigate the transverse momentum of complex fragments with and without in medium corrections. The experimental data yield evidence for a stiff equation of state. A covariant extension of the QMD model is presented, which is applied to very high energy (10…200 AGeV) heavy ion collisions. Particle production and decay of heavy resonances are included. Predictions of the stopping power at AGS and SPS are presented. The importance of secondary scattering and nuclear stopping up to the highest energies is demonstrated. This is particularly important for the recently observed enhancement of strangeness production, which was proposed as a signal for QGP formation.
Ab initio Bogoliubov coupled cluster theory for open-shell nuclei
Signoracci, Angelo J.; Duguet, Thomas; Hagen, Gaute; ...
2015-06-29
Background: Ab initio many-body methods have been developed over the past 10 yr to address closed-shell nuclei up to mass A≈130 on the basis of realistic two- and three-nucleon interactions. A current frontier relates to the extension of those many-body methods to the description of open-shell nuclei. Several routes to address open-shell nuclei are currently under investigation, including ideas that exploit spontaneous symmetry breaking. Purpose: Singly open-shell nuclei can be efficiently described via the sole breaking of U(1) gauge symmetry associated with particle-number conservation as a way to account for their superfluid character. While this route was recently followed withinmore » the framework of self-consistent Green's function theory, the goal of the present work is to formulate a similar extension within the framework of coupled cluster theory. Methods: We formulate and apply Bogoliubov coupled cluster (BCC) theory, which consists of representing the exact ground-state wave function of the system as the exponential of a quasiparticle excitation cluster operator acting on a Bogoliubov reference state. Equations for the ground-state energy and the cluster amplitudes are derived at the singles and doubles level (BCCSD) both algebraically and diagrammatically. The formalism includes three-nucleon forces at the normal-ordered two-body level. The first BCC code is implemented in m scheme, which will permit the treatment of doubly open-shell nuclei via the further breaking of SU(2) symmetry associated with angular momentum conservation. Results: Proof-of-principle calculations in an N max=6 spherical harmonic oscillator basis for 16,18O and 18Ne in the BCCD approximation are in good agreement with standard coupled cluster results with the same chiral two-nucleon interaction, while 20O and 20Mg display underbinding relative to experiment. The breaking of U(1) symmetry, monitored by computing the variance associated with the particle-number operator, is relatively constant for all five nuclei, in both the Hartree-Fock-Bogoliubov and BCCD approximations. Conclusions: The newly developed many-body formalism increases the potential span of ab initio calculations based on single-reference coupled cluster techniques tremendously, i.e., potentially to reach several hundred additional midmass nuclei. The new formalism offers a wealth of potential applications and further extensions dedicated to the description of ground and excited states of open-shell nuclei. Short-term goals include the implementation of three-nucleon forces at the normal-ordered two-body level. Midterm extensions include the approximate treatment of triples corrections and the development of the equation-of-motion methodology to treat both excited states and odd nuclei. Long-term extensions include exact restoration of U(1) and SU(2) symmetries.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sahoo, Babita, E-mail: patra-babita@rediffmail.com; Chakraborty, Suparna, E-mail: banerjee.suparna@hotmail.com; Sahoo, Sukadev, E-mail: sukadevsahoo@yahoo.com
2016-01-15
Momentum and density dependence of single-nucleon potential u{sub τ} (k, ρ, β) is analyzed using a density dependent finite range effective interaction of the Yukawa form. Depending on the choice of the strength parameters of exchange interaction, two different trends of the momentum dependence of nuclear symmetry potential are noticed which lead to two opposite types of neutron and proton effective mass splitting. The 2nd-order and 4th-order symmetry energy of isospin asymmetric nuclear matter are expressed analytically in terms of the single-nucleon potential. Two distinct behavior of the density dependence of 2nd-order and 4th-order symmetry energy are observed depending onmore » neutron and proton effective mass splitting. It is also found that the 4th-order symmetry energy has a significant contribution towards the proton fraction of β-stable npeμ matter at high densities.« less
30 CFR 1219.102 - Method of payment.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Method of payment. 1219.102 Section 1219.102... Resources Revenue DISTRIBUTION AND DISBURSEMENT OF ROYALTIES, RENTALS, AND BONUSES § 1219.102 Method of... Transfer (EFT). Should a State prefer to receive its payment by EFT, it should request this payment method...
Code of Federal Regulations, 2010 CFR
2010-10-01
... specified EFT mechanisms. Governmentwide commercial purchase card means a card that is similar in nature to a commercial credit card that is used to make financing and delivery payments for supplies and services. The purchase card is an EFT method and it may be used as a means to meet the requirement to pay...
31 CFR 206.4 - Collection and payment mechanisms.
Code of Federal Regulations, 2011 CFR
2011-07-01
... with these criteria, specific cash flows will utilize EFT as follows: (1) Fees/fines. EFT will be adopted as the presumed method of collecting fees and fines, especially when these collection cash flows... provide the Service with a recommended mechanism for any new or modified cash flows. The Service will...
31 CFR 206.4 - Collection and payment mechanisms.
Code of Federal Regulations, 2014 CFR
2014-07-01
... with these criteria, specific cash flows will utilize EFT as follows: (1) Fees/fines. EFT will be adopted as the presumed method of collecting fees and fines, especially when these collection cash flows... provide the Service with a recommended mechanism for any new or modified cash flows. The Service will...
31 CFR 206.4 - Collection and payment mechanisms.
Code of Federal Regulations, 2012 CFR
2012-07-01
... with these criteria, specific cash flows will utilize EFT as follows: (1) Fees/fines. EFT will be adopted as the presumed method of collecting fees and fines, especially when these collection cash flows... provide the Service with a recommended mechanism for any new or modified cash flows. The Service will...