Sample records for understanding nuclear quadrupole

  1. Nuclear quadrupole moment of scandium

    SciTech Connect

    Bieron, J.; Grant, I.P. [Mathematical Institute, University of Oxford, 24-29 St. Giles, Oxford OX13LB (United Kingdom); Fischer, C.F. [Department of Computer Science, Vanderbilt University, Nashville, Tennessee 37235 (United States)

    1997-07-01

    The multiconfiguration Dirac-Fock model is employed to evaluate the effects of relativity and electron correlation on the hyperfine interaction constants of the 3d{sup 2} {sup 3}F{sub 3}, {sup 3}F{sub 4}, {sup 1}G{sub 4}, and 3d4p {sup 3}F{sub 4} levels of ScII. The wave function expansions are obtained with the active space method, where configuration state functions of a specific parity and J value are generated by substitutions from the reference configurations to an active set of orbitals. The active set is then increased in a systematic way, allowing the convergence of the hyperfine interaction constants to be studied. The calculated electric quadrupole hyperfine constants, together with previously computed values for other levels of ScII, are used to evaluate the nuclear electric quadrupole moment of isotope 45 of scandium, for which the value Q={minus}0.231(4) b is found. {copyright} {ital 1997} {ital The American Physical Society}

  2. Development of a nuclear quadrupole based technique for

    E-print Network

    Keren, Amit

    Development of a nuclear quadrupole based technique for measuring charge homogeneity, and its application for YBCO SHAHAR LEVY #12;DEVELOPMENT OF A NUCLEAR QUADRUPOLE BASED TECHNIQUE FOR MEASURING CHARGE

  3. Landmine detection with nuclear quadrupole resonance

    Microsoft Academic Search

    Yingyi Tan; Stacy L. Tantum; Leslie M. Collins

    2002-01-01

    Nuclear quadrupole resonance (NQR) technology for the detection of explosives is of crucial importance in an increasing number of applications. For landmine detection, NQR has proven to be highly effective if the NQR sensor is not exposed to radio frequency interference (RFI). Since strong nonstationary RFI in the field is unavoidable, a robust detection method is required. With the aid

  4. Explosives detection by nuclear quadrupole resonance (NQR)

    NASA Astrophysics Data System (ADS)

    Garroway, Allen N.; Buess, Michael L.; Yesinowski, James P.; Miller, Joel B.; Krauss, Ronald A.

    1994-10-01

    Pure nuclear quadrupole resonance (NQR) of 14N nuclei is quite promising as a method for detecting explosives such as RDX and contraband narcotics such as cocaine and heroin in quantities of interest. Pure NQR is conducted without an external applied magnetic field, so potential concerns about damage to magnetically encoded data or exposure of personnel to large magnetic fields are not relevant. Because NQR frequencies of different compounds are quite distinct, we do not encounter false alarms from the NQR signals of other benign materials. We have constructed a laboratory prototype NQR explosives detector which interrogates a volume of 300 liters (10 ft3). This paper presents abbreviated results from a demonstration of the laboratory prototype NQR explosives detector conducted at the Federal Aviation Administration Technical Center in May 1994 on RDX-based explosives.

  5. Polarization enhancement technique for nuclear quadrupole resonance detection.

    PubMed

    Kim, Y J; Karaulanov, T; Matlashov, A N; Newman, S; Urbaitis, A; Volegov, P; Yoder, J; Espy, M A

    2014-01-01

    We demonstrate a dramatic increase in the signal-to-noise ratio (SNR) of a nuclear quadrupole resonance (NQR) signal by using a polarization enhancement technique. By first applying a static magnetic field to pre-polarize one spin subsystem of a material, and then allowing that net polarization to be transferred to the quadrupole subsystem, we increased the SNR of a sample of ammonium nitrate by one-order of magnitude. PMID:24882748

  6. Pure Nuclear Quadrupole Resonance Techniques for Quantum Computation

    NASA Astrophysics Data System (ADS)

    Huang, Wei-Han; Chen, Zilong; Chuang, Isaac

    2003-03-01

    Pure nuclear quadrupole resonance (NQR) at zero magnetic field provides an accessible means for experimentation with the techniques of quantum computation. We present the design and implementation of a novel benchtop NQR apparatus utilizing modern communication electronics, and featuring a high efficiency, low cost class E amplifier with an integrated and tunable probe. Using this apparatus, we study the chlorine and nitrogen NQR resonances in para-dichlorobenzene and sodium nitrite, applying multiple pulse excitation sequences derived using methods of quantum circuits.

  7. Nuclear quadrupole resonance studies project. [spectrometer design and spectrum analysis

    NASA Technical Reports Server (NTRS)

    Murty, A. N.

    1978-01-01

    The participation of undergraduates in nuclear quadrupole resonance research at Grambling University was made possible by NASA grants. Expanded laboratory capabilities include (1) facilities for high and low temperature generation and measurement; (2) facilities for radio frequency generation and measurement with the modern spectrum analyzers, precision frequency counters and standard signal generators; (3) vacuum and glass blowing facilities; and (4) miscellaneous electronic and machine shop facilities. Experiments carried out over a five year period are described and their results analyzed. Theoretical studies on solid state crystalline electrostatic fields, field gradients, and antishielding factors are included.

  8. Nuclear quadrupole resonance detection of explosives: an overview

    NASA Astrophysics Data System (ADS)

    Miller, Joel B.

    2011-06-01

    Nuclear Quadrupole Resonance (NQR) is a spectroscopic technique closely related to Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI). These techniques, and NQR in particular, induce signals from the material being interrogated that are very specific to the chemical and physical structure of the material, but are relatively insensitive to the physical form of the material. NQR explosives detection exploits this specificity to detect explosive materials, in contrast to other well known techniques that are designed to detect explosive devices. The past two decades have seen a large research and development effort in NQR explosives detection in the United States aimed at transportation security and military applications. Here, I will briefly describe the physical basis for NQR before discussing NQR developments over the past decade, with particular emphasis on landmine detection and the use of NQR in combating IED's. Potential future directions for NQR research and development are discussed.

  9. Pure nuclear quadrupole resonance determination of the electric field gradient asymmetry for broad lines

    E-print Network

    Keren, Amit

    Pure nuclear quadrupole resonance determination of the electric field gradient asymmetry for broad nuclear quadrupole resonance (ADNQR) method to determine the electric field gradient asymmetry parameter g in a coil so that the sym- metry axis of the coil is pointing in the br direction. In the experiment

  10. Alignment-to-orientation conversion and nuclear quadrupole resonance D. Budker,1, 2,

    E-print Network

    Budker, Dmitry

    Alignment-to-orientation conversion and nuclear quadrupole resonance D. Budker,1, 2, D. F. Kimball, 2003) The role of alignment-to-orientation conversion (AOC) in nuclear quadrupole resonance (NQR physics. PACS numbers: 76.60.Gv, 32.80.Bx The phenomenon of alignment-to-orientation conver- sion (AOC) [1

  11. The two-frequency nuclear quadrupole resonance for explosives detection

    Microsoft Academic Search

    G. V. Mozjoukhine

    2000-01-01

    The two-frequency nuclear quadrupole resonance (NQR) of14N nuclei is described for purposes of explosives detection. Two applications are known: two-frequency NQR for increasing the\\u000a signal intensity, two-frequency NQR for improved reliability of explosives detection. The two-frequency experiments were carried\\u000a out in hexahydro-1,3,5-trinitro-s-triazine C3H6N6O6 and sodium nitrite NaNO2 as a substitute for octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocycine C4H8N8O8. The two-frequency sequences for NQR are proposed

  12. Optimal filtering in multipulse sequences for nuclear quadrupole resonance detection

    NASA Astrophysics Data System (ADS)

    Osokin, D. Ya.; Khusnutdinov, R. R.; Mozzhukhin, G. V.; Rameev, B. Z.

    2014-05-01

    The application of the multipulse sequences in nuclear quadrupole resonance (NQR) detection of explosive and narcotic substances has been studied. Various approaches to increase the signal to noise ratio (SNR) of signal detection are considered. We discussed two modifications of the phase-alternated multiple-pulse sequence (PAMS): the 180° pulse sequence with a preparatory pulse and the 90° pulse sequence. The advantages of optimal filtering to detect NQR in the case of the coherent steady-state precession have been analyzed. It has been shown that this technique is effective in filtering high-frequency and low-frequency noise and increasing the reliability of NQR detection. Our analysis also shows the PAMS with 180° pulses is more effective than PSL sequence from point of view of the application of optimal filtering procedure to the steady-state NQR signal.

  13. ¹?N nuclear quadrupole resonance study of polymorphism in famotidine.

    PubMed

    Lu?nik, Janko; Pirnat, Janez; Jazbinšek, Vojko; Lavri?, Zoran; Žagar, Veselko; Sr?i?, Stane; Seliger, Janez; Trontelj, Zvonko

    2014-09-01

    (14)N nuclear quadrupole resonance (NQR) in two known polymorphs of famotidine was measured. At room temperature, seven quadrupolar sets of transition frequencies (?(+), ?(-), and ?(0)) corresponding to seven different nitrogen sites in the crystal structure of each of the two polymorphs were found. This confirms the expected ability of NQR to distinguish polymorph B from its analog A. NQR can also measure their ratio in a solid mixture and in the final dosage form, that is, a tablet. The NQR frequencies, line shapes, and tentative assignation to all seven molecular (14)N atoms were obtained. Unravelment of these two entangled NQR spectra presents a valuable contribution to the NQR database and enables studies of some possible correlations therein. Moreover, nondestructive (14)N NQR studies of commercial famotidine tablets can reveal some details of the drug fabrication process connected with compression. PMID:24668530

  14. Nuclear electric quadrupole moment of gold from the molecular method

    NASA Astrophysics Data System (ADS)

    Santiago, Régis Tadeu; Haiduke, Roberto Luiz Andrade

    2015-04-01

    The nuclear electric quadrupole moment (NQM) of gold is reviewed by means of the molecular method and data from as many as 15 linear systems. The electric-field gradients (EFGs) used to this end were obtained with the Dirac-Coulomb Hamiltonian and coupled-cluster theory, CCSD(T) and CCSD-T, by means of an augmented relativistic basis set for gold. The direct approach was found to be inadequate for the diatomic molecules investigated, which is probably due to improper treatment of the static electron correlation. However, these effects are much less relevant for OCAu X (X =F ,Cl ,Br , and I ) complexes. Thus, the indirect version of the molecular method is preferred in this case. Hence, a NQM value of 515(15) mb is determined for 197Au from linear regressions performed with the best EFGs determined for ten of these systems.

  15. A high performance quadrupole quintuplet lens system for the CSIRO–GEMOC nuclear microprobe

    Microsoft Academic Search

    Chris G Ryan; David N Jamieson

    1999-01-01

    A new probe forming system for the CSIRO–GEMOC nuclear microprobe, based on a quadrupole quintuplet lens configuration is described. The lens system uses a novel quadrupole lens design with a 30 mm pole-tip extension, which allows a working distance of 85 mm. Each quadrupole has cut-outs at 45°, in the yoke positioned between poles, to allow unrestricted access for detectors

  16. New technologies: nuclear quadrupole resonance as an explosive and narcotic detection technique

    Microsoft Academic Search

    Vadim S Grechishkin; Nikolai Ya Sinyavskii

    1997-01-01

    Possibilities of detecting nuclear quadrupole resonance (NQR) signals in explosives and drugs are considered. Direct and indirect NQR techniques for searching substances are described and the potentialities of various experimental methods are compared.

  17. Frequency selective detection of nuclear quadrupole resonance (NQR) spin echoes

    NASA Astrophysics Data System (ADS)

    Somasundaram, Samuel D.; Jakobsson, Andreas; Smith, John A. S.; Althoefer, Kaspar A.

    2006-05-01

    Nuclear Quadrupole Resonance (NQR) is a radio frequency (RF) technique that can be used to detect the presence of quadrupolar nuclei, such as the 14N nucleus prevalent in many explosives and narcotics. The technique has been hampered by low signal-to-noise ratios and is further aggravated by the presence of RF interference (RFI). To ensure accurate detection, proposed detectors should exploit the rich form of the NQR signal. Furthermore, the detectors should also be robust to any remaining residual interference, left after suitable RFI mitigation has been employed. In this paper, we propose a new NQR data model, particularly for the realistic case where multiple pulse sequences are used to generate trains of spin echoes. Furthermore, we refine two recently proposed approximative maximum likelihood (AML) detectors, enabling the algorithm to optimally exploit the data model of the entire echo train and also incorporate knowledge of the temperature dependent spin-echo decay time. The AML-based detectors ensure accurate detection and robustness against residual RFI, even when the temperature of the sample is not precisely known, by exploiting the dependencies of the NQR resonant lines on temperature. Further robustness against residual interference is gained as the proposed detector is frequency selective; exploiting only those regions of the spectrum where the NQR signal is expected. Extensive numerical evaluations based on both simulated and measured NQR data indicate that the proposed Frequency selective Echo Train AML (FETAML) detector offers a significant improvement as compared to other existing detectors.

  18. Dynamic nuclear polarization in self-assembled quantum dot by quadrupole effect

    NASA Astrophysics Data System (ADS)

    Liu, Bao; Wang, Ping; Yang, Wen

    2015-03-01

    We apply the recently developed theory of dynamic nuclear polarization to analyze a new nuclear polarization mechanism assisted by quadrupole interaction. This mechanism was proposed to explain a series of experimental observations in a self-assembled quantum dot. We find that although the steady state nuclear polarization agrees with previous works, the rate at which the nuclear spins are polarized is smaller by two orders of magnitude.

  19. Table of nuclear magnetic dipole and electric quadrupole moments

    Microsoft Academic Search

    N. J. Stone

    2005-01-01

    The table is a compilation of experimental measurements of static magnetic dipole and electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin, and parity are given, along with a brief indication of the method and any reference standard used in the particular

  20. A high performance quadrupole quintuplet lens system for the CSIRO-GEMOC nuclear microprobe

    NASA Astrophysics Data System (ADS)

    Ryan, Chris G.; Jamieson, David N.

    1999-10-01

    A new probe forming system for the CSIRO-GEMOC nuclear microprobe, based on a quadrupole quintuplet lens configuration is described. The lens system uses a novel quadrupole lens design with a 30 mm pole-tip extension, which allows a working distance of 85 mm. Each quadrupole has cut-outs at 45°, in the yoke positioned between poles, to allow unrestricted access for detectors into a target chamber at 135° to the beam. Four cut-outs are used to maintain four-fold symmetry. Each lens has a bore of 14 mm. The extra degrees of freedom in the quintuplet configuration allow optimisation to reduce spherical aberration, to minimise spherical and parasitic aberration cross-terms (involving ??), and to attain an orthomorphic demagnification of 67 using a short overall system length (object to target) of 4.7 m. The system also has built-in redundancy; two quadrupole positions are very insensitive to parasitic multipole fields.

  1. The chlorine nuclear quadrupole coupling tensor in chlorotrifluoroethylene

    NASA Astrophysics Data System (ADS)

    Hillig, K. W.; Bittner, E. R.; Kuczkowski, R. L.; Lewis-Bevan, W.; Gerry, M. C. L.

    1988-12-01

    The 273 hyperfine components from 56 rotational transitions of chlorotrifluoroethylene were measured with a Fourier transform microwave spectrometer. A global least-squares fit was made to the rotational constants, quartic distortion constants, and 35Cl quadrupole coupling constants; the RMS deviation of the fit was 1.6 kHz. It is shown that such high-resolution measurements enable ?ab to be determined without the near degeneracies usually necessary with less precise data. The principle tensor quadrupole coupling constants are x?zz = -77.46(10), xxx = 38.85(10), and ?yy = xcc = 38.614(3) MHz. The values are comparable to other vinyl chlorides, removing some anomalies from previous studies.

  2. Methyl internal rotation, dipole moment, and nuclear quadrupole coupling of 2-bromopropane

    NASA Astrophysics Data System (ADS)

    Meyer, Michael; Stahl, Wolfgang; Dreizler, Helmut

    1992-01-01

    The microwave spectrum of 2-bromopropane has been investigated to determine nuclear quadrupole and spin-rotation coupling constants of bromine for the 79Br and 81Br species by microwave Fourier transform spectroscopy. The dipole moment was found to be 2.194 D. From excited torsional states the parameters V3 and V' 12 of the torsional potential function were obtained.

  3. A bi-symmetric square wave Zeeman modulator for nuclear quadrupole resonance.

    PubMed

    Mao, D; Petersen, G L; Bray, P J

    1992-11-01

    A simple circuit has been designed to generate a bi-symmetric square wave Zeeman modulation for the detection of nuclear quadrupole resonance. The square waveform not only provides an optimum result among bi-symmetric modulation waveforms, but also allows the observation of the Zeeman perturbed NQR powder pattern without the need for an extra external magnetic field. PMID:1365735

  4. Polarization of core orbitals and computation of nuclear quadrupole coupling constants using Gaussian basis sets.

    PubMed

    Harbison, Gerard S

    2015-08-01

    Most standard Gaussian basis sets for first row atoms, even large sets designed to converge on a 'complete basis set' limit, systematically overestimate the electric field gradient at nuclear sites for first row atoms, resulting in errors of up to 15% in the computation of nuclear quadrupole coupling constants. This error results from a failure to include tight d functions, which permit the core 1s orbitals to distort under the influence of the field of the nuclear quadrupole. Augmentation of standard basis sets with a single set of single-exponent d functions, matched to the reciprocal square of the nominal 1s radius, reduces these errors by up to 90%. PMID:26037137

  5. Nuclear quadrupole resonance lineshape analysis for different motional models: stochastic Liouville approach.

    PubMed

    Kruk, D; Earle, K A; Mielczarek, A; Kubica, A; Milewska, A; Moscicki, J

    2011-12-14

    A general theory of lineshapes in nuclear quadrupole resonance (NQR), based on the stochastic Liouville equation, is presented. The description is valid for arbitrary motional conditions (particularly beyond the valid range of perturbation approaches) and interaction strengths. It can be applied to the computation of NQR spectra for any spin quantum number and for any applied magnetic field. The treatment presented here is an adaptation of the "Swedish slow motion theory," [T. Nilsson and J. Kowalewski, J. Magn. Reson. 146, 345 (2000)] originally formulated for paramagnetic systems, to NQR spectral analysis. The description is formulated for simple (Brownian) diffusion, free diffusion, and jump diffusion models. The two latter models account for molecular cooperativity effects in dense systems (such as liquids of high viscosity or molecular glasses). The sensitivity of NQR slow motion spectra to the mechanism of the motional processes modulating the nuclear quadrupole interaction is discussed. PMID:22168707

  6. INSTRUMENTS AND METHODS OF INVESTIGATION: New technologies: nuclear quadrupole resonance as an explosive and narcotic detection technique

    NASA Astrophysics Data System (ADS)

    Grechishkin, Vadim S.; Sinyavskii, Nikolai Ya

    1997-04-01

    Possibilities of detecting nuclear quadrupole resonance (NQR) signals in explosives and drugs are considered. Direct and indirect NQR techniques for searching substances are described and the potentialities of various experimental methods are compared.

  7. Nuclear quadrupole resonance of explosives: Simultaneous detection of RDX and PETN in semtex

    Microsoft Academic Search

    R. I. Jenkinson; J. M. Bradley; G. N. Shilstone

    2004-01-01

    We have used nuclear quadrupole resonance (NQR) for the detection of14N in explosives and introduce a new method for the simultaneous detection of the explosives cyclotrimethylene trinitramine\\u000a (RDX) and pentaerythritol tetranitrate (PETN). We have developed an interleaved pulse sequence, which provides efficient excitation\\u000a of both RDX and PETN, to drive a solenoid coil that is doubly resonant at 3.41 and

  8. Exploiting Spin Echo Decay in the Detection of Nuclear Quadrupole Resonance Signals

    Microsoft Academic Search

    Samuel D. Somasundaram; Andreas Jakobsson; John A. S. Smith; Kaspar Althoefer

    2007-01-01

    Nuclear quadrupole resonance (NQR) is a radio-frequency technique that can be used to detect the presence of quadrupolar nuclei, such as the 14N nucleus prevalent in many explosives and narcotics. In a typical application, one observes trains of decaying NQR echoes, in which the decay is governed by the spin echo decay time(s) of the resonant line(s). In most detection

  9. Methods of spectral estimation in local nuclear quadrupole resonance with a dispersion

    Microsoft Academic Search

    V. S. Grechishkin; R. V. Grechishkina; A. A. Persichkin; A. A. Shpilevoi

    2002-01-01

    The spectral estimation in local nuclear quadrupole resonance at a high noise level is performed for the first time using\\u000a the modern techniques of linear prediction (LPSVD) and matrix pencil (ITMPM). The fast Fourier transform with signal accumulation\\u000a does not ensure the required sensitivity in the case of weak signals when the object and the receiver of the spectrometer\\u000a are

  10. High-frequency nuclear quadrupole resonance apparatus for use in pressure cell

    NASA Astrophysics Data System (ADS)

    Iwase, F.; Miyagawa, K.; Kanoda, K.

    2012-06-01

    A high-frequency NMR apparatus for use in pressure cell is described. All components of the resonance circuit are set in the pressure cell. This method makes the resonance frequency much less influenced by large stray capacitance residing at the electrical feedthrough of the pressure cell. With the use of this apparatus, a pressure-induced neutral-ionic phase transition in DMTTF-QBr4 was successfully observed by 79Br nuclear quadrupole resonance, whose resonance frequency is ˜300 MHz.

  11. First Principles Study of Nuclear Quadrupole Interactions in Single and Double Chain DNA and Solid Nucleobases

    NASA Astrophysics Data System (ADS)

    Das, T. P.; Pink, R. H.; Badu, S. R.; Dubey, Archana; Scheicher, R. H.; Saha, H. P.; Chow, Lee; Huang, M. B.

    2009-03-01

    Nuclear Quadrupole Interactions (NQI) of ^17O, ^14N and ^2H nuclei have been studied for free nucleobases and nucleobases in single strand and double strand DNA and in solid state. Our first-principles investigations were carried out using the Gaussian 2003 set of programs to implement the Hartree-Fock procedure combined with many-body effects included using many-body perturbation theory. As expected for NQI in general, many-body effects are found to be small. Results will be presented for the quadrupole coupling constants (e^2qQ) and asymmetry parameters (?) for the nucleobases in the various environments. Trends in e^2qQ and ? in the different environments will be discussed. In the case of the solid nucleobases, comparisons will be made with available experimental data [1] for ^17O nuclei.[3pt] [1] Gang Wu et al., J. Am. Chem. Soc. 124, 1768 (2002)

  12. Multigap superconductivity in locally noncentrosymmetric SrPtAs: An 75As nuclear quadrupole resonance investigation

    NASA Astrophysics Data System (ADS)

    Brückner, F.; Sarkar, R.; Günther, M.; Kühne, H.; Luetkens, H.; Neupert, T.; Reyes, A. P.; Kuhns, P. L.; Biswas, P. K.; Stürzer, T.; Johrendt, D.; Klauss, H.-H.

    2014-12-01

    We report detailed 75As nuclear quadrupole resonance investigations of the locally noncentrosymmetric superconductor SrPtAs. The spin-lattice relaxation studies prove weakly coupled multigap superconductivity. A retardation of the decay in 1 /T1T evidences a nodeless (fully gapped) superconducting state on the complex multipocket Fermi surface, which is consistent with an anisotropic s -wave order parameter and with proposed unconventional f -wave and chiral d -wave symmetries. A quantitative analysis of these models favors the unconventional f -wave state.

  13. Investigation of Wavelet-Based Enhancements to Nuclear Quadrupole Resonance Explosives Detectors

    SciTech Connect

    Kercel, Stephen W.; Dress, William B.; Hibbs, Andrew D.; Barrall, Geoffrey A.

    1998-06-01

    Nuclear Quadrupole Resonance (NQR) is effective for the detection and identification of certain types of explosives such as RDX, PETN and TNT. In explosive detection, the NQR response of certain 14N nuclei present in the crystalline material is probed. The 14N nuclei possess a nuclear quadrupole moment which in the presence of an electric field gradient produces an energy level splitting which may be excited by radio-frequency magnetic fields. Pulsing on the sample with a radio signal of the appropriate frequency produces a transient NQR response which may then be detected. Since the resonant frequency is dependent upon both the quadrupole moment of the 14N nucleus and the nature of the local electric field gradients, it is very compound specific. Under DARPA sponsorship, the authors are using multiresolution methods to investigate the enhancement of operation of NQR explosives detectors used for land mine detection. For this application, NQR processing time must be reduced to less than one second. False alarm responses due to acoustic and piezoelectric ringing must be suppressed. Also, as TNT is the most prevalent explosive found in land mines, NQR detection of TNT must be made practical despite unfavorable relaxation tunes. All three issues require improvement in signal-to-noise ratio, and all would benefit from improved feature extraction. This paper reports some of the insights provided by multiresolution methods that can be used to obtain these improvements. It includes results of multiresolution analysis of experimentally observed NQR signatures for RDX responses and various false alarm signatures in the absence of explosive compounds.

  14. Hartree-Fock Cluster Study of Electronic Structures and Nuclear Quadrupole Interactions in Solid Nucleobases.

    NASA Astrophysics Data System (ADS)

    Scheicher, R. H.; Dubey, Archana; Badu, S. R.; Saha, H. P.; Pink, R. H.; Nagamine, K.; Torikai, E.; Chow, Lee; Das, T. P.

    2008-03-01

    In recent work [1] we have studied nucleobases attached to a CH3 group to simulate the influence of their binding to the sugar rings and the phosphate groups in DNA and RNA and the effect of this binding on the nuclear quadrupole interactions of ^14N, ^17O and ^2H nuclei. Our results from this work have indicated that for ^17O, the binding to the CH3 group moves our results from the free nucleobases closer to the experimentally observed data [2] in the solid nucleobases. We are now investigating the solid nucleobases by the first --principles Hartree-Fock cluster procedure that we have employed earlier for the halogen molecular solids [3]. Our results for the binding energy of an imidazole molecule in the molecular solid system and the ^14N, ^17O and ^2H nuclear quadrupole interaction parameters will be presented. [1] T.P. Das et al (at this APS meeting), [2] Gang Wu et al, J. Am.Chem. Soc. 124, 1768(2002). [3] M.M. Aryal et al Hyperfine Interactions (to be published).

  15. Rotational spectrum, molecular structure, and 201Hg nuclear quadrupole coupling constants of HCNHg

    NASA Astrophysics Data System (ADS)

    Shea, J. A.; Campbell, E. J.

    1992-12-01

    High resolution rotational spectra for 21 isotopic species of the hydrogen cyanide-mercury complex have been measured in the 7-15 GHz region using a Balle/Flygare pulsed Fourier transform microwave spectrometer. Rotational constants and 14N nuclear quadrupole coupling constants are (in MHz), for HC14N202Hg: B0=1265.6627(7), DJ=0.020 669(14), ?N=-0.695(12), and for DC14N202Hg: B0=1201.8338(16), DJ=0.021 213(45), and ?N=-0.748(19). The 201Hg nuclear quadrupole coupling constants are, for HC15N201Hg: -5.97(13) MHz, and for DC15N201Hg: -6.03(24) MHz. The atomic arrangement is HCN...Hg with a zero-point vibrationally averaged center-of-mass separation of 4.05 Å for the most abundant HC14N202Hg species. The equilibrium structure was not determined. HCNHg does not exhibit the extreme centrifugal distortion and isotopic sensitivity effects seen in ArHCN [K. R. Leopold, G. T. Fraser, F. J. Lin, D. D. Nelson, Jr., and W. Klemperer, J. Chem. Phys. 81, 4922 (1984)].

  16. PHYSICAL REVIEW B VOLUME 48, NUMBER 13 1 OCTOBER 1993-1 Determination of the absolute sign of nuclear quadrupole interactions by laser radio-frequency

    E-print Network

    Suter, Dieter

    PHYSICAL REVIEW B VOLUME 48, NUMBER 13 1 OCTOBER 1993-1 Determination of the absolute sign of nuclear quadrupole interactions by laser radio-frequency double-resonance experiments Tilo Blasberg the quadrupole moment of nuclear spins I > + with the electric-field-gradient (EFG) tensor leads to a splitting

  17. (14) N nuclear quadrupole resonance study of piroxicam: confirmation of new polymorphic form v.

    PubMed

    Lavri?, Zoran; Pirnat, Janez; Lužnik, Janko; Puc, Uroš; Trontelj, Zvonko; Sr?i?, Stane

    2015-06-01

    A new polymorphic crystal form of piroxicam was discovered while preparing crystalline samples of piroxicam for (14) N nuclear quadrupole resonance (NQR) analysis. The new crystal form, designated as V, was prepared by evaporative recrystallization from dichloromethane. Three known polymorphic forms (I, II, and III) were also prepared. Our aim was to apply (14) N NQR to characterize the new polymorphic form of piroxicam and compare the results with those of the other known polymorphic forms. Additional analytical methods used for characterization were X-ray powder diffraction (XRPD), thermal analysis, and vibrational spectroscopy. For the first time, a complete set of nine characteristic (14) N NQR frequencies was found for each prepared polymorph of piroxicam. The consistent set of measured frequencies and calculated characteristic quadrupole parameters found for the new polymorphic form V is a convincing evidence that we are dealing with a new form. The already known piroxicam polymorphic forms were characterized similarly. The XRPD results were in accordance with the conclusions of (14) N NQR analysis. The performed study clearly demonstrates a strong potential of (14) N NQR method to be applied as a highly discriminative spectroscopic analytical tool to characterize polymorphic forms. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:1909-1918, 2015. PMID:25776345

  18. Time-reversal symmetry violation in molecules induced by nuclear magnetic quadrupole moments

    E-print Network

    V. V. Flambaum; D. DeMille; M. G. Kozlov

    2014-08-25

    Recent measurements in paramagnetic molecules improved the limit on the electron electric dipole moment (EDM) by an order of magnitude. Time-reversal (T) and parity (P) symmetry violation in molecules may also come from their nuclei. We point out that nuclear T,P-odd effects are amplified in paramagnetic molecules containing deformed nuclei, where the primary effects arise from the T,P-odd nuclear magnetic quadrupole moment (MQM). We perform calculations of T,P-odd effects in the molecules TaN, ThO, ThF$^+$, HfF$^+$, YbF, HgF, and BaF induced by MQMs. We compare our results with those for the diamagnetic TlF molecule, where the T,P-odd effects are produced by the nuclear Schiff moment. We argue that measurements in molecules with MQMs may provide improved limits on the strength of T,P-odd nuclear forces, on the proton, neutron and quark EDMs, on quark chromo-EDMs, and on the QCD $\\theta$-term and CP-violating quark interactions.

  19. arXiv:physics/0302084v124Feb2003 Alignment-to-orientation conversion and nuclear quadrupole resonance

    E-print Network

    Budker, Dmitry

    arXiv:physics/0302084v124Feb2003 Alignment-to-orientation conversion and nuclear quadrupole resonance D. Budker,1, 2, D. F. Kimball,1, S. M. Rochester,1, and J. T. Urban3, § 1 Department of Physics, California 94720-1460 (Dated: February 24, 2003) The role of alignment-to-orientation conversion (AOC

  20. Vol.9, No. 5/May 1992/J. Opt. Soc. Am. B 779 Eu3+ optically detected nuclear quadrupole resonance in

    E-print Network

    Hansen, Peter

    in EuVO4 have been studied with the high-resolution techniques of spectral hole burning and optically to cw spectral hole burning and optically de- tected nuclear quadrupole resonance (ODNQR) using a single the electronic transi- tions and the hole-burning spectra, have been useful in establishing the directions

  1. Theoretical investigation of nuclear quadrupole interactions in DNA at first-principles level

    NASA Astrophysics Data System (ADS)

    Mahato, Dip N.; Dubey, Archana; Pink, R. H.; Scheicher, R. H.; Badu, S. R.; Nagamine, K.; Torikai, E.; Saha, H. P.; Chow, Lee; Huang, M. B.; Das, T. P.

    2008-01-01

    We have studied the nuclear quadrupole interactions (NQI) of the 14N, 17O and 2H nuclei in the nucleobases cytosine, adenine, guanine and thymine in the free state as well as when they are bonded to the sugar ring in DNA, simulated through a CH3 group attached to the nucleobases. The nucleobase uracil, which replaces thymine in RNA, has also been studied. Our results show that there are substantial indirect effects of the bonding with the sugar group in the nucleic acids on the NQI parameters e 2 qQ/h and ?. It is hoped that measurements of these NQI parameters in DNA will be available in the future to compare with our predictions. Our results provide the conclusion that for any property dependent on the electronic structures of the nucleic acids, the effects of the bonding between the nucleobases and the nucleic acid backbones have to be included.

  2. Theoretical investigation of nuclear quadrupole interactions in DNA at first-principles level

    NASA Astrophysics Data System (ADS)

    Mahato, Dip N.; Dubey, Archana; Pink, R. H.; Scheicher, R. H.; Badu, S. R.; Nagamine, K.; Torikai, E.; Saha, H. P.; Chow, Lee; Huang, M. B.; Das, T. P.

    We have studied the nuclear quadrupole interactions (NQI) of the 14N, 17O and 2H nuclei in the nucleobases cytosine, adenine, guanine and thymine in the free state as well as when they are bonded to the sugar ring in DNA, simulated through a CH3 group attached to the nucleobases. The nucleobase uracil, which replaces thymine in RNA, has also been studied. Our results show that there are substantial indirect effects of the bonding with the sugar group in the nucleic acids on the NQI parameters e 2 qQ/h and ?. It is hoped that measurements of these NQI parameters in DNA will be available in the future to compare with our predictions. Our results provide the conclusion that for any property dependent on the electronic structures of the nucleic acids, the effects of the bonding between the nucleobases and the nucleic acid backbones have to be included.

  3. Nuclear quadrupole moment-induced Cotton-Mouton effect in molecules

    SciTech Connect

    Fu, Li-juan, E-mail: lijuan.fu@oulu.fi, E-mail: juha.vaara@iki.fi; Vaara, Juha, E-mail: lijuan.fu@oulu.fi, E-mail: juha.vaara@iki.fi [NMR Research Group, Department of Physics, University of Oulu, P.O. Box 3000, FIN-90014 Oulu (Finland)] [NMR Research Group, Department of Physics, University of Oulu, P.O. Box 3000, FIN-90014 Oulu (Finland)

    2014-01-14

    Nuclear magneto-optic effects could make important contributions to novel, high-sensitivity, and high-resolution spectroscopic and imaging methods that provide nuclear site-specific structural and dynamic information on molecular and materials systems. Here we present a first-principles electronic structure formulation of nuclear quadrupole moment-induced Cotton-Mouton effect in terms of response theory, as well as ab initio and density-functional theory calculations of this phenomenon for a series of molecular liquids: H{sub 2}O, CH{sub 3}NO{sub 2}, CH{sub 3}CH{sub 2}OH, C{sub 6}H{sub 6}, C{sub 6}H{sub 12} (cyclohexane), HI, XeF{sub 2}, WF{sub 5}Cl, and Pt(C{sub 2}dtp){sub 2}. The roles of basis-set convergence, electron correlation, and relativistic effects are discussed. The estimated order of magnitude of the overall ellipticities induced to linearly polarized light is 10{sup ?3}–10{sup ?7} rad/(M cm) for fully spin polarized nuclei. The cases with the largest presently obtained ellipticities should be detectable with modern instrumentation in the Voigt magneto-optic setup, particularly for the heavy nuclei.

  4. 73Ge-Nuclear Magnetic Resonance/Nuclear Quadrupole Resonance Investigation of Magnetic Properties of URhGe

    NASA Astrophysics Data System (ADS)

    Kotegawa, Hisashi; Fukumoto, Kenta; Toyama, Toshihiro; Tou, Hideki; Harima, Hisatomo; Harada, Atsushi; Kitaoka, Yoshio; Haga, Yoshinori; Yamamoto, Etsuji; ?nuki, Yoshichika; Itoh, Kohei M.; Haller, Eugene E.

    2015-05-01

    We report on the 73Ge-nuclear magnetic resonance (NMR)/nuclear quadrupole resonance (NQR) results for the ferromagnetic (FM) superconductor URhGe. The magnitude and direction of the internal field, Hint, and the parameters of the electric field gradient at the Ge site were determined experimentally. By using powdered polycrystalline samples oriented by different methods, the field dependences of NMR shift and nuclear spin relaxation rates for H0 || c (easy axis) and H0 || b were obtained. From the NMR shifts for H0 || b, we confirmed a gradual suppression of the Curie temperature and observed a phase separation near the spin reorientation. The observation of the phase separation gives microscopic evidence that the spin reorientation under H0 || b is of first order at low temperatures. The nuclear spin-lattice relaxation rate 1/T1 indicates that the magnetic fluctuations are suppressed for H0 || c, whereas the fluctuations remain strongly for H0 || b. The enhancements of both 1/T1T and the nuclear spin-spin relaxation rate 1/T2 for H0 || b toward the spin reorientation field suggest that the field-induced superconductivity in URhGe emerges under the magnetic fluctuations along the b- and c-axes.

  5. Understanding nuclear shape phase transitions within SD-pair shell model

    NASA Astrophysics Data System (ADS)

    Li, Lei; Zhang, Yu; Yuan, Xiaoqing; Li, Jiangdan; Luo, Yanan; Pan, Feng; Draayer, Jerry P.

    2015-10-01

    The effect of strength of each interaction on the nuclear shape phase and their transitional patterns are studied in the SD-pair shell model with a Hamiltonian composed of the single-particle energy term, monopole-pairing, quadrupole-pairing and quadrupole-quadrupole interaction for identical nucleon system. It is shown that with quandrupole-pairing interaction and quadrupole-quadrupole interaction strengths set to be 0, the nuclear phase transition from single-particle motion to collective motion can be produced by changing the monopole pairing interaction. With fixed monopole-pairing interaction and quadrupole-pairing interactional strength set to be 0, the like-vibration-rotation shape phase transitional pattern can be produced by changing the quadrupole-quadrupole interaction from 0 to 0.1MeV/r_0^4.

  6. Experimental implementation of quantum information processing by Zeeman-perturbed nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Teles, João; Rivera-Ascona, Christian; Polli, Roberson S.; Oliveira-Silva, Rodrigo; Vidoto, Edson L. G.; Andreeta, José P.; Bonagamba, Tito J.

    2015-03-01

    Nuclear magnetic resonance (NMR) has been widely used in the context of quantum information processing (QIP). However, despite the great similarities between NMR and nuclear quadrupole resonance (NQR), no experimental implementation for QIP using NQR has been reported. We describe the implementation of basic quantum gates and their applications on the creation and manipulation of pseudopure states using linearly polarized radiofrequency pulses under static magnetic field perturbation. The NQR quantum operations were implemented using a single-crystal sample of {KClO}3 and observing ^{35}{Cl} nuclei, which possess spin 3/2 and give rise to a two-qubit system. The results are very promising and indicate that NQR can be successfully used for performing fundamental experiments in QIP. One advantage of NQR in comparison with NMR is that the main interaction is internal to the sample, which makes the system more compact, lowering its cost and making it easier to be miniaturized to solid-state devices. Furthermore, as an example, the study of squeezed spin states could receive relevant contributions from NQR.

  7. Experimental implementation of quantum information processing by Zeeman-perturbed nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Teles, João; Rivera-Ascona, Christian; Polli, Roberson S.; Oliveira-Silva, Rodrigo; Vidoto, Edson L. G.; Andreeta, José P.; Bonagamba, Tito J.

    2015-06-01

    Nuclear magnetic resonance (NMR) has been widely used in the context of quantum information processing (QIP). However, despite the great similarities between NMR and nuclear quadrupole resonance (NQR), no experimental implementation for QIP using NQR has been reported. We describe the implementation of basic quantum gates and their applications on the creation and manipulation of pseudopure states using linearly polarized radiofrequency pulses under static magnetic field perturbation. The NQR quantum operations were implemented using a single-crystal sample of and observing nuclei, which possess spin 3/2 and give rise to a two-qubit system. The results are very promising and indicate that NQR can be successfully used for performing fundamental experiments in QIP. One advantage of NQR in comparison with NMR is that the main interaction is internal to the sample, which makes the system more compact, lowering its cost and making it easier to be miniaturized to solid-state devices. Furthermore, as an example, the study of squeezed spin states could receive relevant contributions from NQR.

  8. A study of the semiconductor compound ?uAlO2 by the method of nuclear quadrupole resonance of Cu

    NASA Astrophysics Data System (ADS)

    Matukhin, V. L.; Khabibulin, I. Kh.; Shul'gin, D. A.; Smidt, S. V.

    2012-07-01

    The method of nuclear quadrupole resonance of Cu (NQR Cu) is used to study the samples of a semiconductor compound CuAlO2. The crystal structure of CuAlO2 belongs to the family of delafossite - the mineral of a basic CuFeO2 structure. Transparent semiconductor oxides, such as CuAlO2, have attracted recent attention as promising thermoelectric materials.

  9. Nuclear quadrupole interaction of111Cd on type-1 Cu-sites in blue copper proteins

    NASA Astrophysics Data System (ADS)

    Tröger, W.; Butz, T.; Danielsen, E.; Bauer, R.; Thoenes, U.; Messerschmidt, A.; Huber, R.; Canters, G. W.; den Blaauwen, T.

    1993-03-01

    The nuclear quadrupole interaction (NQI) of111Cd substituted for Cu(II) on type-1 sites in blue copper proteins is characterized by high values of ?0 in the region of 300 Mrad/s, close to that for the catalytic zinc site in alcohol dehydrogenase. Type-1 Cu has usually two sulfur ligands and two nitrogen ligands and in some cases an oxygen ligand in either a distorted tetrahedral geometry or in a trigonal bipyramidal geometry. The near tetrahedral arrangement together with the ligand sphere containing the same number of sulfur ligands explains the value of ?0 in the blue copper proteins. The present work determined the partial NQI for methionine using the known structure of azurin. This value was then used in the angular overlap model to calculate the NQI for ascorbate oxidase the structure of which is also known and gave good agreement with experiment. NQI data for laccase and stellacyanin the structures of which are unknown, are also given.

  10. Low-power stimulated emission nuclear quadrupole resonance detection system utilizing Rabi transitions

    NASA Astrophysics Data System (ADS)

    Apostolos, John; Mouyos, William; Feng, Judy; Chase, Walter

    2013-06-01

    The application of CW radar techniques to Nuclear Quadrupole Resonance (NQR) detection of nitrogen based explosives and chlorine based narcotics enables the use of low power levels, in the range of 10's of watts, to yield high signal strengths. By utilizing Rabi transitions the nucleus oscillates between states one and two under the time dependent incident electromagnetic field and alternately absorbs energy from the incident field while emitting coherent energy via stimulated emission. Through the application of a cancellation algorithm the incident field is eliminated from the NQR response, allowing the receive signal to be measured while transmitting. The response signal is processed using matched filters of the NQR response which enables the direct detection of explosives. This technology has applicability to the direct detection of explosives and narcotics for security screening, all at safe low power levels, opposed to the current XRay and Millimeter wave screening systems that detect objects that may contain explosives and utilize high power. The quantum mechanics theoretical basis for the approach and an application for a system for security screening are described with empirical results presented to show the effects observed.

  11. Narcotics and explosives detection by 14N pure nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Garroway, Allen N.; Buess, Michael L.; Yesinowski, James P.; Miller, Joel B.

    1994-03-01

    Pure nuclear quadrupole resonance (NQR) of 14N nuclei is quite promising as a method for detecting explosives such as RDX and contraband narcotics such as cocaine and heroin in quantities of interest. Pure NQR is conducted without an external applied magnetic field, so potential concerns about damage to magnetically encoded data or exposure of personnel to large magnetic fields are not relevant. Because NQR frequencies of different compounds are quite distinct, we do not encounter false alarms from the NQR signals of other benign materials. We have constructed a proof-of-concept NQR explosives detector which interrogates a volume of 300 liters (10 ft3). With minimal modification to the existing explosives detector, we can detect operationally relevant quantities of (free base) cocaine within the 300-liter inspection volume in 6 seconds. We are presently extending this approach to the detection of heroin base and also examining 14N and 35,37Cl pure NQR for detection of the hydrochloride forms of both materials. An adaptation of this NQR approach may be suitable for scanning personnel for externally carried contraband and explosives. We first outline the basics of the NQR approach, highlighting strengths and weaknesses, and then present representative results for RDX and cocaine detection. We also present a partial compendium of relevant NQR parameters measured for some materials of interest.

  12. Spectral hole-burning study of hyperfine and nuclear quadrupole interactions of {sup 243}Am{sup 3+} in CaWO{sub 4}

    SciTech Connect

    Liu, G.K. [Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Huang, J. [Department of Physics and Astronomy, University of Wisconsin at Eau Claire, Eau Claire, Wisconsin 54702 (United States)] [Department of Physics and Astronomy, University of Wisconsin at Eau Claire, Eau Claire, Wisconsin 54702 (United States); Abraham, M.M. [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    1997-04-01

    An optical spectral hole-burning technique has been used in study of the hyperfine and nuclear quadrupole interactions of {sup 243}Am{sup 3+} in CaWO{sub 4}. Previous work on {sup 243}Am{sup 3+} in LaCl{sub 3} [Phys. Rev. B {bold 53}, 2385 (1996)] provided an analysis of the nuclear quadrupole interaction in the {sup 7}F{sub 0} ground state and predicted an anomalous nuclear quadrupole interaction in the optically excited state {sup 5}D{sub 1}. In the present work on {sup 243}Am{sup 3+} doped into CaWO{sub 4}, hyperfine energy levels in both the {sup 7}F{sub 0} ground state and the {sup 5}D{sub 1} excited state of an {sup 243}Am{sup 3+} ion have been resolved in spectral hole-burning experiments. A theoretical analysis is reported for the hyperfine and nuclear quadrupole interactions in the non-Kramers doublet of the {sup 5}D{sub 1} excited state of {sup 243}Am{sup 3+} in CaWO{sub 4}. Whereas the crystal-field antishielding effect dominates the ground state nuclear quadrupole splitting, a first order electronic hyperfine interaction dominates the excited state splitting. It is shown that the contribution from the nuclear electric quadrupole interactions in the {sup 5}D{sub 1} excited state is much smaller than that in the {sup 7}F{sub 0} ground state, because the first order nuclear quadrupole interaction with the 5f electrons is canceled in part by the contribution from the lattice interaction. {copyright} {ital 1997} {ital The American Physical Society}

  13. Understanding Nucleons in the Nuclear Medium

    SciTech Connect

    Douglas Higinbotham, Vince Sulkosky

    2010-10-01

    Recent cross section (e,e'pN) short-range correlation experiments have clearly shown the strong dominance of tensor correlations for (e,e'p) missing momenta greater than the Fermi momentum; while recent D(e,e'p)n and 4He(e,e'p)t asymmetry experiments at low missing momentum have shown small changes from the free nucleon form factor. By doing asymmetry experiments as a function of missing momentum, these results can be linked together and observed as a change of sign in the measured asymmetry. This idea will be presented within the context of the recently completed Jefferson Lab Hall A quasi-elastic, polarized 3He(e,e'N) experiments (N=0,p,n,d) where the asymmetries of several reaction channels were measured with three, orthogonal target-spin directions. Together, these various experiments will help us to better understand nucleons in the nuclear medium.

  14. Superconductivity and magnetic fluctuations in Cd(2))Re(2)O(7) via Cd nuclear magnetic resonance and re nuclear quadrupole resonance.

    PubMed

    Vyaselev, O; Arai, K; Kobayashi, K; Yamazaki, J; Kodama, K; Takigawa, M; Hanawa, M; Hiroi, Z

    2002-07-01

    We report Cd nuclear magnetic resonance (NMR) and Re nuclear quadrupole resonance (NQR) studies on Cd(2)Re(2)O(7), the first superconductor among pyrochlore oxides (T(c) approximately 1 K). The Re NQR spectrum at zero magnetic field below 100 K rules out any magnetic or charge order. The spin-lattice relaxation rate below T(c) exhibits a pronounced coherence peak and follows the weak-coupling BCS theory with nearly isotropic energy gap. The results of Cd NMR point to a moderate ferromagnetic enhancement at high temperatures followed by a rapid decrease of the density of states below the structural transition temperature of 200 K. PMID:12097064

  15. Toward understanding the effects of nuclear war

    SciTech Connect

    Grover, H.D.; White, G.F.

    1985-10-01

    The authors discuss the scientific justifications for studying the consequences of nuclear war. The consequences of nuclear war and nuclear winter - biotic impoverishment, climate change, pollution of the air, water, and soil - recapitulate in compressed time the patterns of ecological change humankind is even now imposing on the planet. By studying the biological consequences of nuclear war, important discoveries about the intricate nature of the global ecosystem may be made. Wiser management practices and more thorough appreciation of alterations in the physical and biological environment could results.

  16. Nuclear energy and sustainability: Understanding ITER

    Microsoft Academic Search

    Karine Fiore

    2006-01-01

    Deregulation and new environmental requirements combined with the growing scarcity of fossil resources and the increasing world energy demand lead to a renewal of the debate on tomorrow's energies. Specifically, nuclear energy, which has undeniable assets, faces new constraints. On the one hand, nuclear energy is very competitive and harmless to greenhouse effect. From this point, it seems to be

  17. The nuclear quadrupole moment of Li: Refined calculations of electric field gradients in LiH, LiF, and LiCl

    NASA Astrophysics Data System (ADS)

    Urban, Miroslav; Sadlej, Andrzej J.

    1990-10-01

    A series of high-level correlated calculations of the electric field gradient at the Li nucleus have been performed for LiH, LiF, and LiCl. The present results lead to a refined "molecular" value of the nuclear quadrupole moment of 7Li, Q( 7Li)=-4.01 e fm 2 which is an excellent agreement with the most recent result (-4.03±0.06 e fm 2) derived from the nuclear scattering data.

  18. Crossed-coil detection of two-photon excited nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Eles, Philip T.; Michal, Carl A.

    2005-08-01

    Applying a recently developed theoretical framework for determining two-photon excitation Hamiltonians using average Hamiltonian theory, we calculate the excitation produced by half-resonant irradiation of the pure quadrupole resonance of a spin-3/2 system. This formalism provides expressions for the single-quantum and double-quantum nutation frequencies as well as the Bloch-Siegert shift. The dependence of the excitation strength on RF field orientation and the appearance of the free-induction signal along an axis perpendicular to the excitation field provide an unmistakable signature of two-photon excitation. We demonstrate single- and double-quantum excitation in an axially symmetric system using 35Cl in a single crystal of potassium chlorate ( ?Q = 28 MHz) with crossed-coil detection. A rotation plot verifies the orientation dependence of the two-photon excitation, and double-quantum coherences are observed directly with the application of a static external magnetic field.

  19. Nuclear Quadrupole Interactions of 7Li and 51V in a Li3VO4 Single Crystal Studied by Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Lim, Ae Ran; Park, Sung Ho; Kim, Jung Nam; Jang, Min Su

    2003-02-01

    The rotation patterns of the nuclear magnetic resonances of 7Li (I=3/2) and 51V (I=7/2) in the nonlinear optical Li3VO4 single crystal were measured in two mutually perpendicular crystal planes. From these results, the quadrupole coupling constants and the asymmetry parameters at room temperature were determined for the first time as follows: e2qQ/h=53.68± 2 kHz and ?=0.169 for 7Li, and e2qQ/h=1.44± 2 MHz and ?=0 for 51V. The symmetry for the electric field gradient (EFG) of V ions surrounded by four oxygen atoms is higher than that of Li ions surrounded by four oxygen atoms. The principal axes of the EFG tensor are a=Y, b=Z, c=X for 7Li, and a=b=X, c=Z for 51V nucleus. Also, the 7Li and the 51V spin-lattice relaxation rates were measured, and the behavior is quite similar for both nuclei. The measured relaxation rate was found to be linear in the square of the temperature. The Raman process with a T2 dependence is considered to be more effective than the direct process for nuclear quadrupole relaxation.

  20. First-principles study of boron oxygen hole centers in crystals: Electronic structures and nuclear hyperfine and quadrupole parameters

    SciTech Connect

    Li Zucheng; Pan Yuanming [Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2 (Canada)

    2011-09-15

    The electronic structures, nuclear hyperfine coupling constants, and nuclear quadrupole parameters of fundamental boron oxygen hole centers (BOHCs) in zircon (ZrSiO{sub 4}, I4{sub 1}/amd) and calcite (CaCO{sub 3}, R3c) have been investigated using ab initio Hartree-Fock (HF) and various density functional theory (DFT) methods based on the supercell models with all-electron localized basis sets. Both exact HF exchange and appropriate correlation functionals are important in describing the BOHCs, and the parameter-free hybrid method based on Perdew, Burke, and Ernzerhof density functionals (PBE0) turns out to be the best DFT method in reproducing the electron paramagnetic resonance (EPR) data. Our results reveal three distinct types of simple-spin (S = 1/2) [BO{sub 3}]{sup 2-} centers in calcite: (i) the classic [BO{sub 3}]{sup 2-} radical with the D{sub 3h} symmetry and the unpaired spin equally distributed on the three oxygen atoms (i.e. the O{sub 3}{sup 5-} type); (ii) the previously reported [BO{sub 2}]{sup 0} center with the unpaired spin equally distributed on two of the three oxygen atoms (O{sub 2}{sup 3-}); and (iii) a new variety with {approx}90% of its unpaired spin localized on one (O{sup -}) of the three oxygen atoms with a long B-O bond (1.44 A). Calculations confirm the unusual [BO{sub 4}]{sup 0} center in zircon and show it to arise from a highly distorted configuration with 90% of the unpaired spin on one oxygen atom that has a considerably longer B-O bond (1.68 A) than its three counterparts (1.45 A). The calculated magnitudes and directions of {sup 11}B and {sup 17}O hyperfine coupling constants and nuclear quadrupole constants for the [BO{sub 4}]{sup 0} center in zircon are in excellent agreement with the 15 K EPR experimental data. These BOHCs are all characterized by a small negative spin density on the central B atom arising from spin polarization. Our calculations also demonstrate that the spin densities on BOHCs are affected substantially by crystalline environments, and so periodic boundary treatment, such as the supercell scheme, is a must in accounting for the electronic and spin structures of BOHCs in crystals. These atomistic and electronic models of BOHCs in the crystalline matrices provide new insights into their precursors and counterparts in glasses and other amorphous materials.

  1. Understanding Nuclear Receptors Using Computational Methods

    PubMed Central

    Ai, Ni; Krasowski, Matthew D.; Welsh, William J; Ekins, Sean

    2010-01-01

    Nuclear receptors (NRs) are important targets for therapeutic drugs. NRs regulate transcriptional activities through binding to ligands and interacting with a number of regulating proteins. Computational methods can provide insights into essential ligand-receptor and protein-protein interactions. These in turn have facilitated the discovery of novel agonists and antagonists with high affinity and specificity as well as aiding in the prediction of toxic side effects of drugs by identifying possible off-target interactions. Here, we review the application of computational methods towards several clinically important NRs (with special emphasis on PXR) and discuss their use for screening and predicting the toxic side effects of xenobiotics. PMID:19429508

  2. Understanding nuclear receptors using computational methods.

    PubMed

    Ai, Ni; Krasowski, Matthew D; Welsh, William J; Ekins, Sean

    2009-05-01

    Nuclear receptors (NRs) are important targets for therapeutic drugs. NRs regulate transcriptional activities through binding to ligands and interacting with several regulating proteins. Computational methods can provide insights into essential ligand-receptor and protein-protein interactions. These in turn have facilitated the discovery of novel agonists and antagonists with high affinity and specificity as well as have aided in the prediction of toxic side effects of drugs by identifying possible off-target interactions. Here, we review the application of computational methods toward several clinically important NRs (with special emphasis on PXR) and discuss their use for screening and predicting the toxic side effects of xenobiotics. PMID:19429508

  3. Nuclear quadrupole interaction of {sup 243}Am{sup 3+} in LaCl{sub 3} measured via optical spectral-hole burning

    SciTech Connect

    Liu, G.K.; Cao, R.; Beitz, J.V. [Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    1996-02-01

    An optical spectral-hole burning technique has been used to study the nuclear quadrupole splitting in the ground state of {sup 243}Am{sup 3+} in LaCl{sub 3}. The observed splitting is consistent with Am{sup 3+} ions on an axially symmetric site. The nuclear quadrupole coupling constant {ital P}={minus}75{plus_minus}1 MHz for the {sup 7}{ital F}{sub 0} ground state is obtained based on an effective operator Hamiltonian. The crystal-field antishielding effect dominates whereas contributions from the 5{ital f} electrons and from the pseudoquadrupole interaction are negligible ({ital P}{sub 5{ital f}}/{ital P}{sub latt}=0.03). The Sternheimer antishielding factor, {gamma}{sub {infinity}}={minus}154, is determined and comparison is made between the actinide ion Am{sup 3+} and its rare-earth analogy Eu{sup 3+}. {copyright} {ital 1996 The American Physical Society.}

  4. Nuclear Quadrupole Spin-Lattice Relaxation and Critical Dynamics of Ferroelectric Crystals

    Microsoft Academic Search

    G. Bonera; F. Borsa; A. Rigamonti

    1970-01-01

    The effect on the nuclear spin-lattice relaxation of the anomalous temperature dependence of generalized unstable lattice modes near the ferroelectric transition is investigated both theoretically and experimentally. Expressions for the relaxation rate near Tc are derived for typical cases of critical dynamics of ferroelectric crystals. For the case of undamped soft-phonon modes it is shown that, on the basis of

  5. Nuclear quadrupole resonance of barium in BaBiO3 and BaPbO3

    NASA Astrophysics Data System (ADS)

    Savosta, M. M.; Doroshev, V. D.; Borodin, V. A.; Pashkevich, Yu. G.; Kamenev, V. I.; Tarasenko, T. N.; Englich, J.; Kohout, J.; Soldatov, A. G.; Barilo, S. N.; Shiryaev, S. V.

    2001-05-01

    The nuclear quadrupole resonance (NQR) on Ba nuclei was studied in four samples of BaBiO3 prepared in different ways and, in addition, in BaPbO3. The spectrum of 137Ba at T=4.2 K consists of a relatively broad line centered near 18 MHz for all BaBiO3 samples and near 13 MHz for BaPbO3. The integrated intensity of the 137Ba resonance in the ceramic sample of BaBiO3 synthesized at 800 °C is approximately twice as large as that in ceramic samples and a single crystal prepared at 930-1080 °C. The decrease of the NQR signal can be attributed to the partial disordering of charge-disproportionated Bi ions on the two inequivalent sites. The broadening of the resonance indicates that local distortions of the crystal structure exist in both compounds. The point-charge model was used to analyze the electric-field gradient on the Ba sites.

  6. Experimental and theoretical investigations of the nuclear quadrupole resonance of 127I in orthoperiodic acid, H 5IO 6

    NASA Astrophysics Data System (ADS)

    Ramaprabhu, S.; Rama Rao, K. V. S.; Weiss, Alarich

    1983-12-01

    Pure nuclear quadrupole resonance of 127I in H 5IO 6 has been reported to occur at 44.976 MHz (m = ± {3}/{2}?m = ± {1}/{2} transition) and 83.960 MHz (m = ± {5}/{2}? m = ± {3}/{2} transition) at 296 K (ref. 1). Using an externally quenched frequency modulated super regenerative spectrometer Zeeman studies have been performed at 296 K on single crystals of H 5IO 6 growm from aqueous solution by observation of the ± {sol3}/{2}?± {1}/{2} transition. The zero-splitting locus method has been employed for the determination of the EFG parameters. The data show that there are two physically inequivalent sites, having average asymmetry parameters, ?, of 0.25, located in the unit cell. The maximum field gradient is found to lie along the short bond I-O(2) as suggested by Rama Rao and Weiss (ref. 1). The EFG parameters obtained by detailed molecular orbital calculations (CNDO/2 and INDO method) are compared with the experimental results.

  7. 14N nuclear quadrupole resonance study of phase transitions of 1M and 2Or polytypes of potassium hexacyanoferrate (III)

    NASA Astrophysics Data System (ADS)

    Murgich, Juan; Abanero, Jose A.; Santana R., Magaly; Capparelli, Mario V.

    1986-11-01

    14N nuclear quadrupole resonance (NQR) frequencies were measured between 77-328 K for simple monoclinic (1M) and orthorhombic (2Or) polytypes of potassium hexacyanoferrate (III) (KFR). A reversible first order transition was found at 133 K for 1M and at 138 K for 2Or polytype. The transition was interpreted in terms of the coupling of a quasisoft rotatory mode with a temperature dependent tilt motion of the complex ion. An irreversible interpolytype transition produced by internal strains was observed in a sample formed by 1M and 2Or polytypes and repeatedly cycled between around 80-140 K and room temperature. Selective broadening of lines observed in only a pair of N atoms of each hexacyanoferrate ion was attributed to the occurrence of one dimensional disorder of neighboring K ions. The disorder disappeared after sample recrystallization. It was found that low crystallization rates produced only the 1M structure while high rates increased the occurrence of the 2Or over 1M polytype and even produced a third polytype. Annealing of KFR for two weeks at 160 °C produced minor changes in polytypic composition thus showing a high energy barrier for interpolytypic conversion. The results obtained in KFR are explained in terms of the theory of order-disorder structures in layered compounds.

  8. Charge dependence and electric quadrupole effects on single-nucleon removal in relativistic and intermediate energy nuclear collisions

    NASA Technical Reports Server (NTRS)

    Norbury, J. W.; Townsend, L. W. (Principal Investigator)

    1990-01-01

    Single-nucleon removal in relativistic and intermediate energy nucleus-nucleus collisions is studied using a generalization of Weizsacker-Williams theory that treats each electromagnetic multipole separately. Calculations are presented for electric dipole and quadrupole excitations and incorporate a realistic minimum impact parameter, Coulomb recoil corrections, and the uncertainties in the input photonuclear data. Discrepancies are discussed. The maximum quadrupole effect to be observed in future experiments is estimated and also an analysis of the charge dependence of the electromagnetic cross sections down to energies as low as 100 MeV/nucleon is made.

  9. Charge Dependence and Electric Quadrupole Effects on Single-Nucleon Removal in Relativistic and Intermediate Energy Nuclear Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    1992-01-01

    Single nucleon removal in relativistic and intermediate energy nucleus-nucleus collisions is studied using a generalization of Weizsacker-Williams theory that treats each electromagnetic multipole separately. Calculations are presented for electric dipole and quadrupole excitations and incorporate a realistic minimum impact parameter, Coulomb recoil corrections, and the uncertainties in the input photonuclear data. Discrepancies are discussed. The maximum quadrupole effect to be observed in future experiments is estimated and also an analysis of the charge dependence of the electromagnetic cross sections down to energies as low as 100 MeV/nucleon is made.

  10. Nuclear Cardiology Objectives Understand the principles of myocardial perfusion and blood flow, factors

    E-print Network

    Ford, James

    Nuclear Cardiology Objectives Knowledge · Understand the principles of myocardial perfusion. · Know the differences between the various radioisotopes used in nuclear cardiology, including physician. · Participation in monthly Nuclear Cardiology Tutorial. · Independent reading of Nuclear

  11. {sup 63}Cu and {sup 197}Au nuclear quadrupole moments from four-component relativistic density-functional calculations using correct long-range exchange

    SciTech Connect

    Thierfelder, Christian; Schwerdtfeger, Peter; Saue, Trond [Centre of Theoretical Chemistry and Physics, Institute of Fundamental Sciences, Massey University (Auckland Campus), Private Bag 102904, North Shore MSC, Auckland (New Zealand); Laboratoire de Chimie Quantique, Institut de Chimie de Strasbourg, LC3-UMR7177 CNRS/Universite Louis Pasteur, 4 Rue Blaise Pascal, F-67000 Strasbourg (France)

    2007-09-15

    The electric field gradient in late transition metal compounds is incorrectly determined by most density functionals. We show that the coupling of short-range density functional based with long-range wave function based methods using a reparametrization of the Coulomb-attenuated Becke three-parameter Lee-Yang-Parr approximation gives reliable results for the electric field gradients of copper and gold for a series of compounds. This results in nuclear quadrupole moments of -0.208 b for {sup 63}Cu and +0.526 b for {sup 197}Au in good agreement with experimental values of -0.220(15) and +0.547(16)b, respectively.

  12. Understanding China`s nuclear non-proliferation policy

    SciTech Connect

    Nichols, P.J.

    1999-06-01

    China`s nuclear-export activities appear to contradict its official non-proliferation policy. Scrutiny of China`s nuclear exports and non- proliferation commitments indicate an adherence to strict `letter-of-the-law` obligations. Yet, China`s commitment to the norms and values of the non- proliferation regime is controversial. The difference between China`s legal obligations and the international norms of acceptable export behavior is a function of the ambiguity inherent in international treaties and agreements. Stephen Meyer`s motivational hypothesis is used to evaluate China`s nuclear-export decision-making process. China`s motivational profile created by the combination of 16 incentives and disincentives on one hand, and international and domestic conditions on the other. Two case studies are used to illustrate that this profile is not static. As environmental conditions and China`s national priorities change, so does China`s motivational profile. In the past, U. S. attempts to alter China`s nuclear-export activities were successful when the targeted changes were congruent with China`s national priorities. For the United States to influence China`s future nuclear-export activities, it must first understand China`s national priorities and determine the corresponding export motivations that influence China`s decision-making process. The United States should then work to change conditions, which would shift the balance of incentives and disincentives, thereby changing the outcome of China`s cost-benefit calculus.

  13. Calculation of the nuclear quadrupole resonance spectra of YBa/sub 2/Cu/sub 3/O/sub 7/minus/x/

    SciTech Connect

    Winter, N.W.; Violet, C.E.

    1989-06-01

    Nuclear quadrupole resonance (NQR) and nuclear magnetic resonance (NMR) studies on /sup 63,65/Cu have demonstrated the the resonance properties of these nuclei can give important information about the electronic structure of the high temperature superconductor YBa/sub 2/Cu/sub 3/O/sub 7/minus/x/ as well as the exchange coupling energy between the Cu(2) sites. Measurements for various oxygen stoichiometries have given insight into the effect of oxygen content on the valence state of the Cu. In the work reported here, the electric field gradient (EFG) tensors at the Cu(1) and Cu(2) sites in YBa/sub 2/Cu/sub 3/O/sub 7/minus/x/, have been determined from calculations on large clusters for x = 0 and 1. 13 refs., 2 tabs.

  14. The Rotational Spectra, Structures, and Chlorine Nuclear Electric Quadrupole Coupling Constants for a Family of Three Halogenated Cyclic Alkenes, C_nF2n-4Cl_2: n = 4, 5, and 6

    NASA Astrophysics Data System (ADS)

    Long, B. E.; Arsenault, E. A.; Hansen, Lucas; Cooke, S. A.

    2014-06-01

    Microwave spectra for a family of three halogenated cyclic alkenes, C_nF2n-4Cl_2; n = 4, 5, and 6, have been observed and analyzed. Rotational constants, quartic centrifugal distortion constants, and nuclear electric quadrupole coupling constants for a total of 9 isotopologues have been reported. These molecules are near oblate tops containing two quadrupolar nuclei. Data was first obtained via a chirp pulse Fourier transform microwave (FTMW) spectrometer, and then further analyzed with a Balle-Flygare type FTMW spectrometer to determine the chlorine nuclear electric quadrupole coupling constants. The spectroscopic parameters for all 9 species will be presented and compared.

  15. Large-scale multiconfigurational Dirac-Fock calculations of the hyperfine-structure constants and determination of the nuclear quadrupole moment of {sup 49}Ti

    SciTech Connect

    Bieron, J. [Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagiellonski, Reymonta 4, 30-059 Krakow (Poland)] [Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagiellonski, Reymonta 4, 30-059 Krakow (Poland); Fischer, C.F. [Department of Computer Science, Vanderbilt University, Nashville, Tennessee 37235 (United States)] [Department of Computer Science, Vanderbilt University, Nashville, Tennessee 37235 (United States); Grant, I.P. [Mathematical Institute, University of Oxford, 24-29 St. Giles, Oxford OX1 3LB (United Kingdom)] [Mathematical Institute, University of Oxford, 24-29 St. Giles, Oxford OX1 3LB (United Kingdom)

    1999-06-01

    The multiconfiguration Dirac-Fock (MCDF) model is employed to compute the hyperfine interaction constants of the 3d{sup 2}4s {sup 2}D{sub 3/2}, 3d{sup 2}4s {sup 2}D{sub 5/2}, 3d{sup 3} {sup 2}G{sub 7/2}, 3d{sup 3} {sup 2}G{sub 9/2}, and 3d{sup 3} {sup 2}P{sub 3/2} levels of titanium ion. The wave function expansions are obtained with the active space expansion method, where configuration state functions of a specific parity and {ital J} value are generated by substitutions from the reference configurations to an active set of orbitals. The active set is then increased in a systematic way, allowing the convergence of the expectation values to be achieved. The calculated electric quadrupole hyperfine constants are used to evaluate the nuclear electric quadrupole moment of isotope 49 of titanium, for which the value Q=0.247(11)b is found. {copyright} {ital 1999} {ital The American Physical Society}

  16. A theoretical study of 17O, 14N and 2H nuclear quadrupole coupling tensors in the real crystalline structure of acetaminophen

    NASA Astrophysics Data System (ADS)

    Behzadi, Hadi; Esrafili, Mehdi D.; Hadipour, Nasser L.

    2007-03-01

    A systematic computational investigation was carried out to characterize the 17O, 14N and 2H electric field gradient, EFG, tensors in the acetaminophen real crystalline structure. To include the hydrogen bonding effects in the calculations, the most probable interacting molecules with the target molecule in the crystalline phase were considered through the various molecular clusters. The calculations were performed with the B3LYP method and 6-311++G ?? and 6-311+G ? standard basis sets using the Gaussian 98 suite of programs. Calculated EFG tensors were used to evaluate the 17O, 14N, and 2H nuclear quadrupole resonance, NQR, parameters in acetaminophen crystalline structure, which are in good agreement with the available experimental data. The difference between the calculated NQR parameters of the monomer and molecular clusters shows how much hydrogen bonding interactions affect the EFG tensors of each nucleus. These results indicate that both O-H⋯O and N-H⋯O hydrogen bonding have major influence on the NQR parameters. Moreover, the quantum chemical calculation indicated that the intermolecular hydrogen bonding interactions play an essential role in determining the relative orientation of quadrupole coupling principal components in the molecular frame axes.

  17. Effect of Intermolecular Hydrogen Bonding on the Nuclear Quadrupole Interaction in Imidazole and its Derivatives as Studied by ab initio Molecular Orbital Calculations

    NASA Astrophysics Data System (ADS)

    Nakamura, Nobuo; Masui, Hirotsugo; Ueda, Takahiro

    2000-02-01

    Ab initio Hartree-Fock molecular orbital calculations were applied to the crystalline imidazole and its derivatives in order to examine systematically the effect of possible N-H---N type hydrogen bond-ing on the nuclear quadrupole interaction parameters in these materials. The nitrogen quadrupole coupling constant (QCC) and the asymmetry parameter (?) of the electric field gradient (EFG) were found to depend strongly on the size of the molecular clusters, from single molecule, to dimer, trimer and to the infinite molecular chain, i.e., crystalline state, implying that the intermolecular N-H -N hydrogen bond affects significantly the electronic structure of imidazole molecule. A certain correla-tion between the QCC of 14N and the N-H bond distance R was also found and interpreted on the basis of the molecular orbital theory. However, we found that the value of the calculated EFG at the hy-drogen position of the N-H group, or the corresponding QCC value of 2 H, increases drastically as R-3 when R is shorter than about 0.1 nm, due probably to the inapplicability of the Gaussian basis sets to the very short chemical bond as revealed in the actual imidazole derivatives. We suggested that the ob-served N-H distances in imidazole derivatives should be re-examined.

  18. Hyperfine and Nuclear Quadrupole Tensors of Nitrogen Donors in the QA Site of Bacterial Reaction Centers: Correlation of the Histidine N? Tensors with Hydrogen Bond Strength

    PubMed Central

    2015-01-01

    X- and Q-band pulsed EPR spectroscopy was applied to study the interaction of the QA site semiquinone (SQA) with nitrogens from the local protein environment in natural abundance 14N and in 15N uniformly labeled photosynthetic reaction centers of Rhodobacter sphaeroides. The hyperfine and nuclear quadrupole tensors for His-M219 N? and Ala-M260 peptide nitrogen (Np) were estimated through simultaneous simulation of the Q-band 15N Davies ENDOR, X- and Q-band 14,15N HYSCORE, and X-band 14N three-pulse ESEEM spectra, with support from DFT calculations. The hyperfine coupling constants were found to be a(14N) = 2.3 MHz, T = 0.3 MHz for His-M219 N? and a(14N) = 2.6 MHz, T = 0.3 MHz for Ala-M260 Np. Despite that His-M219 N? is established as the stronger of the two H-bond donors, Ala-M260 Np is found to have the larger value of a(14N). The nuclear quadrupole coupling constants were estimated as e2Qq/4h = 0.38 MHz, ? = 0.97 and e2Qq/4h = 0.74 MHz, ? = 0.59 for His-M219 N? and Ala-M260 Np, respectively. An analysis of the available data on nuclear quadrupole tensors for imidazole nitrogens found in semiquinone-binding proteins and copper complexes reveals these systems share similar electron occupancies of the protonated nitrogen orbitals. By applying the Townes–Dailey model, developed previously for copper complexes, to the semiquinones, we find the asymmetry parameter ? to be a sensitive probe of the histidine N?–semiquinone hydrogen bond strength. This is supported by a strong correlation observed between ? and the isotropic coupling constant a(14N) and is consistent with previous computational works and our own semiquinone-histidine model calculations. The empirical relationship presented here for a(14N) and ? will provide an important structural characterization tool in future studies of semiquinone-binding proteins. PMID:25026433

  19. Understanding the nature of nuclear power plant risk

    SciTech Connect

    Denning, R. S. [Ohio State Univ., 201 West 19th Avenue, Columbus, OH 43210-1142 (United States)

    2012-07-01

    This paper describes the evolution of understanding of severe accident consequences from the non-mechanistic assumptions of WASH-740 to WASH-1400, NUREG-1150, SOARCA and today in the interpretation of the consequences of the accident at Fukushima. As opposed to the general perception, the radiological human health consequences to members of the Japanese public from the Fukushima accident will be small despite meltdowns at three reactors and loss of containment integrity. In contrast, the radiation-related societal impacts present a substantial additional economic burden on top of the monumental task of economic recovery from the nonnuclear aspects of the earthquake and tsunami damage. The Fukushima accident provides additional evidence that we have mis-characterized the risk of nuclear power plant accidents to ourselves and to the public. The human health risks are extremely small even to people living next door to a nuclear power plant. The principal risk associated with a nuclear power plant accident involves societal impacts: relocation of people, loss of land use, loss of contaminated products, decontamination costs and the need for replacement power. Although two of the three probabilistic safety goals of the NRC address societal risk, the associated quantitative health objectives in reality only address individual human health risk. This paper describes the types of analysis that would address compliance with the societal goals. (authors)

  20. Application of Nuclear Quadrupole Resonance Relaxometry to Study the Influence of the Environment on the Surface of the Crystallites of Powder

    NASA Astrophysics Data System (ADS)

    Sinyavsky, Nikolay Ya.; Mershiev, Ivan G.; Kupriyanova, Galina S.

    2015-06-01

    The results of the experimental study of the influence of the environment surrounding the surface of the crystallites of a KClO3 powder on the distribution of the spin-spin and spin-lattice relaxation times for 35Cl nuclear quadrupole resonance are described. It was found that the distributions of the spin-lattice relaxation times are unimodal and distributions of the spin-spin relaxation times are bimodal for all samples we studied. T1 - T2 and T1? - T2 correlations by means of the two-dimensional (2D) inverse Laplace transform are obtained. The efficiency of the method for the study of surface phenomena in solids is demonstrated.

  1. Evaluation of nitrogen nuclear hyperfine and quadrupole coupling parameters for the proximal imidazole in myoglobin-azide, -cyanide, and -mercaptoethanol complexes by electron spin echo envelope modulation spectroscopy.

    PubMed

    Magliozzo, R S; Peisach, J

    1993-08-24

    Electron spin echo envelope modulation (ESEEM) spectroscopy and computer simulation of spectra has been used to evaluate the nitrogen nuclear hyperfine and quadrupole coupling parameters for the proximal imidazole nitrogen directly coordinated to iron in three low-spin heme complexes, myoglobin-azide, -cyanide, and -mercaptoethanol (MbN3, MbCN, and MbRS). The variability in the weak electron-nuclear coupling parameters reveals the electronic flexibility within the heme group that depends on properties of the exogenous ligands. For example, the isotropic component of the nitrogen nuclear hyperfine coupling ranges from 4.4 MHz for MbN3 to 2.2 MHz for both MbCN and MbRS. The weaker coupling in MbCN and MbRS is taken as evidence for delocalization of unpaired electron spin from iron into the exogenous anionic ligands. The value of e2Qq, the nuclear quadrupole coupling constant for the axial imidazole nitrogen in MbCN and MbRS, was 2.5 MHz but was significantly larger, 3.2 MHz, in MbN3. This large value is considered evidence for a weakened sigma bond between the proximal imidazole and ferric iron in this form, and for a feature contributing to the origin of the high spin-low spin equilibrium exhibited by MbN3 [Beetlestone, J., & George, P. (1964) Biochemistry 5, 707-714]. The ESEEM results have allowed a correlation to be made between the orientation of the g tensor axes, the orientation of the p-pi orbital of the proximal imidazole nitrogen, and sigma- and pi-bonding features of the axial ligands. Furthermore, the proximal imidazole is suggested to act as a pi-acceptor in low-spin heme complexes in order to support strong sigma electron donation from the lone pair orbital to iron. An evaluation of the nitrogen nuclear hyperfine coupling parameters for the porphyrin pyrrole sites in MbRS reveals a large inequivalence in isotropic components consistent with an orientation of rhombic axes (and g tensor axes) that eclipses the Fe-Npyrrole vector directions. PMID:8395204

  2. Introduction A major goal in nuclear physics is to understand how

    E-print Network

    Mihaila, Bogdan

    Introduction A major goal in nuclear physics is to understand how nuclear binding, stability article 20 Nuclear Physics News, Vol. 13, No. 1, 2003 Ab Initio Calcula the accurate calculation of nuclear matrix ele- ments needed for some tests of the standard model

  3. Nuclear Propulsion for Space, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Corliss, William R.; Schwenk, Francis C.

    The operation of nuclear rockets with respect both to rocket theory and to various fuels is described. The development of nuclear reactors for use in nuclear rocket systems is provided, with the Kiwi and NERVA programs highlighted. The theory of fuel element and reactor construction and operation is explained with particular reference to rocket…

  4. Microwave spectra and structures of KrAuF, KrAgF, and KrAgBr; 83Kr nuclear quadrupole coupling and the nature of noble gas-noble metal halide bonding.

    PubMed

    Thomas, Jason M; Walker, Nicholas R; Cooke, Stephen A; Gerry, Michael C L

    2004-02-01

    Microwave spectra of the complexes KrAuF and KrAgBr have been measured for the first time using a cavity pulsed jet Fourier transform microwave spectrometer. The samples were prepared by laser ablation of the metal from its solid and allowing the resulting plasma to react with an appropriate precursor (Kr, plus SF6 or Br2) contained in the backing gas of the jet (usually Ar). Rotational constants; geometries; centrifugal distortion constants; vibration frequencies; and 197Au, 79Br, and 81Br nuclear quadrupole coupling constants have all been evaluated. The complexes are unusually rigid and have short Kr-Au and Kr-Ag bonds. The 197Au nuclear quadrupole coupling constant differs radically from its value in an AuF monomer. In addition 83Kr hyperfine structure has been measured for KrAuF and the previously reported complex KrAgF. The geometry of the latter has been reevaluated. Large values for the 83Kr nuclear quadrupole coupling constants have been found for both complexes. Both the 197Au and 83Kr hyperfine constants indicate a large reorganization of the electron distribution on complex formation. A thorough assessment of the nature of the noble gas-noble metal bonding in these and related complexes (NgMX; Ng is a noble gas, M is a noble metal, and X is a halogen) has been carried out. The bond lengths are compared with sums of standard atomic and ionic radii. Ab initio calculations have produced dissociation energies along with Mulliken populations and other data on the electron distributions in the complexes. The origins of the rigidity, dissociation energies, and nuclear quadrupole coupling constants are considered. It is concluded that there is strong evidence for weak noble gas-noble metal chemical bonding in the complexes. PMID:14746496

  5. Standard test method for analysis of isotopic composition of uranium in nuclear-grade fuel material by quadrupole inductively coupled plasma-mass spectrometry

    E-print Network

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This test method is applicable to the determination of the isotopic composition of uranium (U) in nuclear-grade fuel material. The following isotopic weight percentages are determined using a quadrupole inductively coupled plasma-mass spectrometer (Q-ICP-MS): 233U, 234U, 235U, 236U, and 238U. The analysis can be performed on various material matrices after acid dissolution and sample dilution into water or dilute nitric (HNO3) acid. These materials include: fuel product, uranium oxide, uranium oxide alloys, uranyl nitrate (UNH) crystals, and solutions. The sample preparation discussed in this test method focuses on fuel product material but may be used for uranium oxide or a uranium oxide alloy. Other preparation techniques may be used and some references are given. Purification of the uranium by anion-exchange extraction is not required for this test method, as it is required by other test methods such as radiochemistry and thermal ionization mass spectroscopy (TIMS). This test method is also described i...

  6. Nuclear Reactors for Space Power, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Corliss, William R.

    The historical development of rocketry and nuclear technology includes a specific description of Systems for Nuclear Auxiliary Power (SNAP) programs. Solar cells and fuel cells are considered as alternative power supplies for space use. Construction and operation of space power plants must include considerations of the transfer of heat energy to…

  7. Sources of Nuclear Fuel, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Singleton, Arthur L., Jr.

    A brief outline of the historical landmarks in nuclear physics leading to the use of nuclear energy for peaceful purposes introduces this illustrated booklet. The distribution of known sources of uranium ores is mapped and some details about the geology of each geographical area given. Methods of prospective, mining, milling, refining, and fuel…

  8. Very high gradient quadrupoles

    Microsoft Academic Search

    J. Strait

    2001-01-01

    High gradient superconducting quadrupoles are an essential component of high energy hadron colliders, both in the arcs and in the insertions. The highest performance quadrupoles today are those for the Large Hadron Collider (LHC) at CERN. These 56 to 70 mm aperture magnets, developed in Europe, the United States, and Japan, reach gradients on the order of 250 T\\/m, which

  9. Toward Understanding the Microscopic Origin of Nuclear Clustering

    SciTech Connect

    Okolowicz, J. [Institute of Nuclear Physics, Polish Academy of Sciences; Nazarewicz, Witold [UTK/ORNL/University of Warsaw; Ploszajczak, M. [Grand Accelerateur National d'Ions Lourds (GANIL)

    2013-01-01

    Open Quantum System (OQS) description of a many-body system involves interaction of Shell Model (SM) states through the particle continuum. In realistic nuclear applications, this interaction may lead to collective phenomena in the ensemble of SM states. We claim that the nuclear clustering is an emergent, near-threshold phenomenon, which cannot be elucidated within the Closed Quantum System (CQS) framework. We approach this problem by investigating the near-threshold behavior of Exceptional Points (EPs) in the realistic Continuum Shell Model (CSM). The consequences for the alpha-clustering phenomenon are discussed.

  10. The Role of Nuclear Physics in Understanding the Cosmos and the Origin of Elements

    SciTech Connect

    Balantekin, A. B. [Physics Department, University of Wisconsin, Madison WI 53706 (United States)

    2011-05-06

    This popular lecture, given in the conference celebrating contributions of Akito Arima to physics on the occasion of his 80th anniversary, outlines the role of nuclear physics in understanding the origin of elements.

  11. The Role of Nuclear Physics in Understanding the Cosmos and the Origin of Elements

    E-print Network

    A. B. Balantekin

    2011-02-04

    This popular lecture, given in the conference celebrating contributions of Akito Arima to physics on the occasion of his 80th anniversary, outlines the role of nuclear physics in understanding the origin of elements.

  12. Super hybrid quadrupoles

    NASA Astrophysics Data System (ADS)

    Tosin, Giancarlo; Palma Sanchez, Priscila; Citadini, James Francisco; Castro Vergasta, Camila

    2012-05-01

    A new model of quadrupole composed of permanent magnetic material, coils and soft magnetic material is proposed for the new Brazilian Synchrotron Light Source (Sirius). These quadrupoles must have flexibility about 30% of the total gradient in order to correct the linear effects caused by the insertion devices on the beam dynamics. This flexibility is obtained using coils while permanent magnets are used to supply the constant gradient.

  13. Understanding Nuclear Receptor Form and Function Using Structural Biology

    PubMed Central

    Rastinejad, Fraydoon; Huang, Pengxiang; Chandra, Vikas; Khorasanizadeh, Sepideh

    2013-01-01

    Nuclear receptors (NR) are a major transcription factor family whose members selectively bind small molecule lipophilic ligands and transduce those signals into specific changes in gene programs. For over two decades, structural biology efforts were directed exclusively on the individual ligand binding domains (LBDs) or DNA binding domains (DBDs) of NRs. These analyses revealed the basis for both ligand and DNA binding, and also revealed receptor conformations representing both the activated and repressed states. Additionally, crystallographic studies explained how NR LBD surfaces recognize discrete portions of transcriptional coregulators. The many structural snapshots of LBDs have also guided the development of synthetic ligands with therapeutic potential. Yet, the exclusive structural focus on isolated NR domains has made it difficult to conceptualize how all the NR polypeptide segments are coordinated physically and functionally in the context of receptor quaternary architectures. Newly emerged crystal structures of the PPAR?-RXR? heterodimer and HNF-4? homodimer have recently revealed the higher order organizations of these receptor complexes on DNA, as well as the complexity and uniqueness of their domain-domain interfaces. These emerging structural advances promise to better explain how signals in one domain can be allosterically transmitted to distal receptor domains, also providing much better frameworks for guiding future drug discovery efforts. PMID:24103914

  14. Progress in Understanding the Nuclear Equation of State at the Quark Level

    SciTech Connect

    A.W. Thomas; P.A.M. Guichon

    2007-01-03

    At the present time there is a lively debate within the nuclear community concerning the relevance of quark degrees of freedom in understanding nuclear structure. We outline the key issues and review the impressive progress made recently within the framework of the quark-meson coupling model. In particular, we explain in quite general terms how the modification of the internal structure of hadrons in-medium leads naturally to three- and four-body forces, or equivalently, to density dependent effective interactions.

  15. Three-Dimensional Nuclear Chart--Understanding Nuclear Physics and Nucleosynthesis in Stars

    ERIC Educational Resources Information Center

    Koura, Hiroyuki

    2014-01-01

    Three-dimensional (3D) nuclear charts were created using toy blocks, which represent the atomic masses per nucleon number and the total half-lives for each nucleus in the entire region of the nuclear mass. The bulk properties of the nuclei can be easily understood by using these charts. Subsequently, these charts were used in outreach activities…

  16. High gradient superconducting quadrupoles

    SciTech Connect

    Lundy, R.A.; Brown, B.C.; Carson, J.A.; Fisk, H.E.; Hanft, R.H.; Mantsch, P.M.; McInturff, A.D.; Remsbottom, R.H.

    1987-07-01

    Prototype superconducting quadrupoles with a 5 cm aperture and gradient of 16 kG/cm have been built and tested as candidate magnets for the final focus at SLC. The magnets are made from NbTi Tevatron style cable with 10 inner and 14 outer turns per quadrant. Quench performance and multipole data are presented. Design and data for a low current, high gradient quadrupole, similar in cross section but wound with a cable consisting of five insulated conductors are also discussed.

  17. Quadrupole Collectivity in Neutron Deficient Sn Isotopes

    NASA Astrophysics Data System (ADS)

    Gade, Alexandra

    2014-03-01

    One of the overarching goals of nuclear physics is the development of a comprehensive model of the atomic nucleus with predictive power across the nuclear chart. Of particular importance for the development of nuclear models is experimental data that consistently track the effect of isospin and changed binding, for example. The chain of Sn isotopes has been a formidable testing ground for nuclear models as some spectroscopic data is available from N = Z = 50 100Sn in the proximity of the proton dripline to 134Sn, beyond the very neutron-rich doubly magic nucleus 132Sn. In even-even nuclei, the electromagnetic quadrupole excitation strength is a measure of quadrupole collectivity, sensitive to the presence of shell gaps, nuclear deformation, and nucleon-nucleon correlations, for example. In the Sn isotopes, this transition strength has been reported from 104Sn to 130Sn, spanning a chain of 14 even-even Sn isotopes. The trend is asymmetric with respect to midshell and not even the largest-scale shell-model calculations have been able to describe the evolution of transition strength across the isotopic chain without varying effective charges. Implications will be discussed. This work was supported by the National Science Foundation under Grant No. PHY-1102511.

  18. Understanding the Challenges in the Transition from Film Radiography in the Nuclear Power Industry

    SciTech Connect

    Meyer, Ryan M.; Ramuhalli, Pradeep; Moran, Traci L.; Nove, Carol A.; Pardini, Allan F.

    2012-09-01

    Nondestructive examination (NDE) applications in the nuclear power industry using film radiography are shrinking due to the advent of modern digital imaging technologies and advances in alternative inspection methods that do not present an ionizing radiation hazard. Technologies that are used routinely in the medical industry for patient diagnosis are being adapted to industrial NDE applications including the detection and characterization of defects in welds. From the user perspective, non-film inspection techniques provide several advantages over film techniques. It is anticipated that the shift away from the application of film radiography in the nuclear power industry represents an irreversible trend. The U.S. Nuclear Regulatory Commission (NRC) has noted this trend in the U.S. nuclear power industry and will be working to ensure that the effectiveness and reliability of component inspections is not compromised by this transition. Currently, specific concerns are associated with 1) obtaining a fundamental understanding of how inspection effectiveness and reliability may be impacted by this transition and 2) ensuring training standards and qualifications remain compatible with modern industrial radiographic practice. This paper discusses recent trends in industrial radiography and assesses their advantages and disadvantages from the perspective of nuclear power plant component inspections.

  19. Understanding the X chromosome inactivation cycle in mice: a comprehensive view provided by nuclear transfer.

    PubMed

    Oikawa, Mami; Inoue, Kimiko; Shiura, Hirosuke; Matoba, Shogo; Kamimura, Satoshi; Hirose, Michiko; Mekada, Kazuyuki; Yoshiki, Atsushi; Tanaka, Satoshi; Abe, Kuniya; Ishino, Fumitoshi; Ogura, Atsuo

    2014-02-01

    During mouse development, imprinted X chromosome inactivation (XCI) is observed in preimplantation embryos and is inherited to the placental lineage, whereas random XCI is initiated in the embryonic proper. Xist RNA, which triggers XCI, is expressed ectopically in cloned embryos produced by somatic cell nuclear transfer (SCNT). To understand these mechanisms, we undertook a large-scale nuclear transfer study using different donor cells throughout the life cycle. The Xist expression patterns in the reconstructed embryos suggested that the nature of imprinted XCI is the maternal Xist-repressing imprint established at the last stage of oogenesis. Contrary to the prevailing model, this maternal imprint is erased in both the embryonic and extraembryonic lineages. The lack of the Xist-repressing imprint in the postimplantation somatic cells clearly explains how the SCNT embryos undergo ectopic Xist expression. Our data provide a comprehensive view of the XCI cycle in mice, which is essential information for future investigations of XCI mechanisms. PMID:24172050

  20. Impact hazard mitigation: understanding the effects of nuclear explosive outputs on comets and asteroids

    SciTech Connect

    Clement, Ralph R C [Los Alamos National Laboratory; Plesko, Catherine S [Los Alamos National Laboratory; Bradley, Paul A [Los Alamos National Laboratory; Conlon, Leann M [Los Alamos National Laboratory

    2009-01-01

    The NASA 2007 white paper ''Near-Earth Object Survey and Deflection Analysis of Alternatives'' affirms deflection as the safest and most effective means of potentially hazardous object (PHO) impact prevention. It also calls for further studies of object deflection. In principle, deflection of a PHO may be accomplished by using kinetic impactors, chemical explosives, gravity tractors, solar sails, or nuclear munitions. Of the sudden impulse options, nuclear munitions are by far the most efficient in terms of yield-per-unit-mass launched and are technically mature. However, there are still significant questions about the response of a comet or asteroid to a nuclear burst. Recent and ongoing observational and experimental work is revolutionizing our understanding of the physical and chemical properties of these bodies (e.g ., Ryan (2000) Fujiwara et al. (2006), and Jedicke et al. (2006)). The combination of this improved understanding of small solar-system bodies combined with current state-of-the-art modeling and simulation capabilities, which have also improved dramatically in recent years, allow for a science-based, comprehensive study of PHO mitigation techniques. Here we present an examination of the effects of radiation from a nuclear explosion on potentially hazardous asteroids and comets through Monte Carlo N-Particle code (MCNP) simulation techniques. MCNP is a general-purpose particle transport code commonly used to model neutron, photon, and electron transport for medical physics reactor design and safety, accelerator target and detector design, and a variety of other applications including modeling the propagation of epithermal neutrons through the Martian regolith (Prettyman 2002). It is a massively parallel code that can conduct simulations in 1-3 dimensions, complicated geometries, and with extremely powerful variance reduction techniques. It uses current nuclear cross section data, where available, and fills in the gaps with analytical models where data are not available. MCNP has undergone extensive verification and validation and is considered the gold-standard for particle transport. (Forrest B. Brown, et al., ''MCNP Version 5,'' Trans. Am. Nucl. Soc., 87, 273, November 2002.) Additionally, a new simulation capability using MCNP has become available to this collaboration. The first results of this new capability will also be presented.

  1. Development of electrostatic quadrupoles for heavy ion fusion

    SciTech Connect

    Faltens, A.; Seidl, P. [Lawrence Berkeley National Lab., CA (United States)

    1996-12-31

    High-voltage electrostatic quadrupoles are used for focusing ion beams at low energies in the induction linac approach to heavy ion driven inertial confinement fusion for the production of electrical power. The transportable beam line charge density depends linearly on the operating voltage of the quadrupoles, so an experimental program was conducted to find the voltage breakdown dependence on the overall size of the quadrupoles which would then allow determination of the best geometry and operating voltage. The quadrupole electrodes are usually stainless steel cylinders with hemispherical end caps, mounted on stainless steel end plates. The end plates are precisely positioned with respect to each other and the vacuum chamber with alumina insulators with shielded triple points. It is advantageous for beam transport to employ an array of multiple beams for which a rather large number of interdigitated electrodes forms an array of quadrupoles. The tradeoffs between very large numbers of small channels and a smaller number of large channels, and the dependence of the choice on the voltage breakdown dependence is discussed. With present understanding, the optimum is about 100 beamlets focused with quadrupoles which have a beam aperture radius of about 2.3 cm and are operated with about 150 kV between electrodes.

  2. Implosion of quadrupole gravitational waves

    E-print Network

    W. B. Bonnor; M. S. Piper

    1996-10-10

    Einstein's vacuum equations are solved up to the second approximation for imploding quadrupole gravitational waves. The implosion generates a black hole singularity irrespective of the strength of the waves.

  3. Microstructural Examination to Aid in Understanding Friction Bonding Fabrication Technique for Monolithic Nuclear Fuel

    SciTech Connect

    Karen L. Shropshire

    2008-04-01

    Monolithic nuclear fuel is currently being developed for use in research reactors, and friction bonding (FB) is a technique being developed to help in this fuel’s fabrication. Since both FB and monolithic fuel are new concepts, research is needed to understand the impact of varying FB fabrication parameters on fuel plate characteristics. This thesis research provides insight into the FB process and its application to the monolithic fuel design by recognizing and understanding the microstructural effects of varying fabrication parameters (a) FB tool load, and (b) FB tool face alloy. These two fabrication parameters help drive material temperature during fabrication, and thus the material properties, bond strength, and possible formation of interface reaction layers. This study analyzed temperatures and tool loads measured during those FB processes and examined microstructural characteristics of materials and bonds in samples taken from the resulting fuel plates. This study shows that higher tool load increases aluminum plasticization and forging during FB, and that the tool face alloy helps determine the tool’s heat extraction efficacy. The study concludes that successful aluminum bonds can be attained in fuel plates using a wide range of FB tool loads. The range of tool loads yielding successful uranium-aluminum bonding was not established, but it was demonstrated that such bonding can be attained with FB tool load of 48,900 N (11,000 lbf) when using a FB tool faced with a tungsten alloy. This tool successfully performed FB, and with better results than tools faced with other materials. Results of this study correlate well with results reported for similar aluminum bonding techniques. This study’s results also provide support and validation for other nuclear fuel development studies and conclusions. Recommendations are offered for further research.

  4. Sodium-23 and potassium-39 nuclear magnetic resonance relaxation in eye lens. Examples of quadrupole ion magnetic relaxation in a crowded protein environment.

    PubMed Central

    Stevens, A; Paschalis, P; Schleich, T

    1992-01-01

    Single and multiple quantum nuclear magnetic resonance (NMR) spectroscopic techniques were used to investigate the motional dynamics of sodium and potassium ions in concentrated protein solution, represented in this study by cortical and nuclear bovine lens tissue homogenates. Both ions displayed homogeneous biexponential magnetic relaxation behavior. Furthermore, the NMR relaxation behavior of these ions in lens homogenates was consistent either with a model that assumed the occurrence of two predominant ionic populations, "free" and "bound," in fast exchange with each other or with a model that assumed an asymmetric Gaussian distribution of correlation times. Regardless of the model employed, both ions were found to occur in a predominantly "free" or "unbound" rapidly reorienting state. The fraction of "bound" 23Na+, assuming a discrete two-site model, was approximately 0.006 and 0.017 for cortical and nuclear homogenates, respectively. Corresponding values for 39K+ were 0.003 and 0.007, respectively. Estimated values for the fraction of "bound" 23Na+ or 39K+ obtained from the distribution model (tau C greater than omega L-1) were less than or equal to 0.05 for all cases examined. The correlation times of the "bound" ions, derived using either a two-site or distribution model, yielded values that were at least one order of magnitude smaller than the reorientational motion of the constituent lens proteins. This observation implies that the apparent correlation time for ion binding is dominated by processes other than protein reorientational motion, most likely fast exchange between "free" and "bound" environments. The results of NMR visibility studies were consistent with the above findings, in agreement with other studies performed by non-NMR methods. These studies, in combination with those presented in the literature, suggest that the most likely role for sodium and potassium ions in the lens appears to be the regulation of cell volume by affecting the intralenticular water chemical potential. Images FIGURE 4 PMID:1600073

  5. Understanding ploidy complex and geographic origin of the Buchloe dactyloides genome using cytoplasmic and nuclear marker systems

    Microsoft Academic Search

    H. Budak; R. C. Shearman; O. Gulsen; I. Dweikat

    2005-01-01

    Characterizing and inferring the buffalograss [Buchloe dactyloides (Nutt.) Engelm.] genome organization and its relationship to geographic distribution are among the purposes of the buffalograss\\u000a breeding and genetics program. This buffalograss study was initiated to: (1) better understand the buffalograss ploidy complex\\u000a using various marker systems representing nuclear and organelle genomes; (2) determine whether the geographic distribution\\u000a was related to nuclear

  6. 33S NMR spectroscopy. 4. Substituent effects on the 33S nuclear quadrupole coupling constants and electric field gradient in 3- and 4-substituted benzenesulphonates studied by DFT calculations in vacuo and in aqueous solution

    NASA Astrophysics Data System (ADS)

    Musio, Roberta; Sciacovelli, Oronzo

    2013-11-01

    33S nuclear quadrupole coupling constants (?) and the principal component of the electric field gradient (qzz) in 3- and 4-substituted benzenesulphonates are dependent on the electronic properties of substituents. Previously reported experimental results were interpreted with the support of theoretical calculations in vacuo and in aqueous solution. To obtain good reproducibility of the experimental data, the introduction of the solvent effect into the calculations was mandatory. The best results were obtained at the B3LYP/6-311++G(3d,p) level using the Integral Equation Formalism for the Polarisable Continuum Model (IEF-PCM) to reproduce the solvent effect. In vacuo, for neutral substituents, the substituent effect on sulphur qzz can be mainly ascribed to electronic interactions (i.e., inductive and mesomeric effects transmitted through the aromatic ring). For charged substituents (3-NH3+,4-NH3+,4-NH(CH)2+,3-SO3-,4-SO3-,3-O,4-O) there is also a relevant contribution of coulomb origin, owed to the electric charge on the substituent itself, which polarises the S-O and C-S bonds. In aqueous solution, short-range solute-solvent interactions (i.e., hydrogen bonding) can be neglected, and the solvent effect can be adequately described considering the electrostatic interactions between the sbnd C-SO3- moiety and the electric charges on the surface of the cavity embedding the molecule within the solvent. These interactions amplify the electronic contribution transmitted through the aromatic ring and partially annihilate the coulomb contribution of the intrinsic charges of substituents. The results of the Natural Bond Orbital (NBO) analysis support these results and demonstrate that the polarisation of the S-O and S-C bonds and oxygen lone pairs due to solvent interactions produces only a redistribution of the electron density around the sulphur nucleus, thus inducing the variations of qzz.

  7. Superconducting clusters and phase separation in Pr1+xBa2-xCu3O7+?: A 63,65Cu nuclear quadrupole resonance and zero-field NMR study

    NASA Astrophysics Data System (ADS)

    Grévin, B.; Berthier, Y.; Mendels, P.; Collin, G.

    2000-02-01

    We present a study on the effect of the Pr3+ substitution for Ba2+ in the Pr1+xBa2-xCu3O7+? system, where small superconducting fractions have been observed in some of the samples with x in the range 0.1nuclear quadrupole resonance (NQR) and zero-field NMR are reported for the x=0.3 sample Pr1.3Ba1.7Cu3O7+? in which the largest superconducting fraction has been detected below 90 K. 63,65Cu NQR in this sample shows the presence of a fraction of metallic copper in the CuO2 planes and confirms that the substitution of Pr onto Ba sites leads to oxygen interchain sites O(5) occupancy. The existence of two different magnetic Cu(2) sites is evidenced for x=0.3 from the comparison of the Cu(2) zero-field NMR in the x=0 and x=0.3 samples. The whole set of results is interpreted in the framework of a phase separation mechanism in the CuO2 planes induced by the Ba/Pr substitution. Three characteristic domains are involved, in which respectively localized holes are present, no holes are transferred, and mobile holes reside. We present a model where the observed superconductivity is due to a segregation of local defects in the structure which gives a distribution of clusters containing mobile holes. A local weakening of the Pr4f-O2p hybridization by the Pr/Ba substitution is argued to explain the presence of these clusters.

  8. Vibrational analysis of tevatron quadrupoles

    SciTech Connect

    Moore, C.D.

    1996-01-01

    There is motion of the beam in the Tevatron on various time scales from years (slow motion of the tunnel) to tenths of milliseconds (betatron tune motion). This paper will discuss a very restricted frequency range from a few Hertz to a few tens of Hertz. The assumption behind the analysis presented here is that the beam motion is due to transverse motion of Tevatron quadrupoles. The introduction of the low beta insertions in the Tevatron has necessitated the installation of remote monitoring sensors on the quadrupoles since the quadrupoles are strong and are located in regions where the beta functions are large. In general the magnet and support structures are mirror symmetric around the interaction points.

  9. Electromagnetic Design of Superconducting Quadrupoles

    E-print Network

    Todesco, E

    2006-01-01

    We study how the critical gradient depends on the coil lay-out in a superconducting quadrupole for particle accelerators. We show that the results relative to a simple sector coil are well representative of the coil lay-outs that have been used to build several quadrupoles in the past 30 years. Using a semi-analytical approach we derive a formula that gives that critical gradient as a function of the coil cross-sectional area, of the magnet aperture, and of the superconducting cable parameters. This formula is used to evaluate the efficiency of several types of coil lay-outs (shell, racetrack, block, open mid-plane).

  10. Physical implications of the use of primitive and traceless electric quadrupole moments

    NASA Astrophysics Data System (ADS)

    Gunning, M. J.; Raab, R. E.

    Theories of certain electromagnetic effects, such as chiral phenomena in fluids and crystals and gyrotropic birefringence in antiferromagnetic crystals, require the inclusion of electric quadrupole contributions for a full description of the effect. In a number of these theories the electric quadrupole moment is defined to be traceless, as indeed is the general practice for such moments in nuclear physics. It is shown that, when the traceless quadrupole moment is used in the derivation of the wave equation that describes light propagation through an optically active uniaxial medium, this equation and properties derived from it, in particular refractive index, depend in general on the arbitrary origin used to specify the quadrupole moment. This is physically unacceptable for an observable property of a substance. By contrast, this defect does not occur if the definition of the primitive quadrupole moment is adopted, namely qr r . beta

  11. LCLS Undulator Quadrupole Fiducialization Plan

    SciTech Connect

    Wolf, Zachary; Levashov, Michael; Lundahl, Eric; Reese, Ed; LeCocq, Catherine; Ruland, Robert; /SLAC; ,

    2010-11-24

    This note presents the fiducialization plan for the LCLS undulator quadrupoles. The note begins by summarizing the requirements for the fiducialization. A discussion of the measurement equipment is presented, followed by the methods used to perform the fiducialization and check the results. This is followed by the detailed fiducialization plan in which each step is enumerated. Finally, the measurement results and data storage formats are presented. The LCLS is made up of 33 assemblies consisting of an undulator, quadrupole, beam finder wire, and other components mounted on a girder. The components must be mounted in such a way that the beam passes down the axis of each component. In this note, we describe how the ideal beam axis is related to tooling balls on the quadrupole. This step, called fiducialization, is necessary because the ideal beam axis is determined magnetically, whereas tangible objects must be used to locate the quadrupole. The note begins with the list of fiducialization requirements. The laboratory in which the work will be performed and the relevant equipment is then briefly described. This is followed by a discussion of the methods used to perform the fiducialization and the methods used to check the results. A detailed fiducialization plan is presented in which all the steps of fiducialization are enumerated. A discussion of the resulting data files and directory structure concludes the note.

  12. Quadrupole splitting in sodium ferrocyanide

    Microsoft Academic Search

    M. J. Evans; P. J. Black

    1970-01-01

    Mossbauer spectra from a single crystal of hydrated sodium ferrocyanide indicate a shift in line position with crystal orientation which is consistent with a quadrupole splitting of 0.56 gamma o. Voigt profile analysis of spectra from powders indicates a smaller broadening of the Lorentz component, 0.27 Gamma o; the inconsistency is explained by preferred orientation in the absorber samples.

  13. Nuclear {sup 111}Cd probes detect a hidden symmetry change at the {gamma} {sup {yields} {alpha}} transition in cerium considered isostructural for 60 years

    SciTech Connect

    Tsvyashchenko, A. V., E-mail: tsvyash@hppi.troitsk.r [Russian Academy of Sciences, Vereshchagin Institute for High Pressure Physics (Russian Federation); Nikolaev, A. V. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Velichkov, A. I.; Salamatin, A. V. [Joint Institute for Nuclear Research (Russian Federation); Fomicheva, L. N. [Russian Academy of Sciences, Vereshchagin Institute for High Pressure Physics (Russian Federation); Ryasny, G. K.; Sorokin, A. A. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Kochetov, O. I. [Joint Institute for Nuclear Research (Russian Federation); Budzynski, M. [Curie-Sklodowska University, Institute of Physics (Poland)

    2010-10-15

    We use the time-differential perturbed angular correlation technique to study nuclear electric quadrupole hyperfine interactions of probe {sup 111}Cd nuclei in cerium lattice sites at room temperature under pressures up to 8 GPa. We have found that the well known {gamma} {sup {yields} {alpha}} phase transition in cerium is not isostructural. In {alpha}-Ce, the probe {sup 111}Cd nuclei reveal a quadrupole electron charge density component that is absent in {gamma}-Ce. The hidden spacial structure of electronic quadrupoles in {alpha}-Ce is triple-q antiferroquadrupolar, as was suggested in [14]. We relate our findings to the current understanding of the {gamma} {sup {yields} {alpha}} phase transition and also report on nuclear quadrupole interactions in other high-pressure phases of cerium: {alpha}'' (C2/m space symmetry) and {alpha}' ({alpha}-U structure).

  14. RADIATION RESISTANT HTS QUADRUPOLES FOR RIA.

    SciTech Connect

    GUPTA,R.; ANERELLA,M.; HARRISON,M.; ET AL.

    2004-10-03

    Extremely high radiation, levels with accumulated doses comparable to those in nuclear reactors than in accelerators, and very high heat loads ({approx}15 kw) make the quadrupole magnets in the fragment separator one of the most challenging elements of the proposed Rare Isotope Accelerator (RIA). Removing large heat loads, protecting the superconducting coils against quenching, the long term survivability of magnet components, and in particular, insulation that can retain its functionality in such a harsh environment, are the major challenges associated with such magnets. A magnet design based on commercially available high temperature superconductor (HTS) and stainless steel tape insulation has been developed. HTS will efficiently remove these large heat loads and stainless steel can tolerate these large radiation doses. Construction of a model magnet has been started with several coils already built and tested. This paper presents the basic magnet design, results of the coil tests, the status and the future plans. In addition, preliminary results of radiation calculations are also presented.

  15. Effects of spin vacancies on the correlated spin dynamics in La{sub 2}Cu{ital {sub 1{minus}x}}Zn{ital {sub x}}O{sub 4} from {sup 63}Cu nuclear quadrupole resonance relaxation

    SciTech Connect

    Carretta, P.; Rigamonti, A.; Sala, R. [Department of Physics A. Volta, Unita INFM and Sezione INFN, Via Bassi 6, I-27100 Pavia (Italy)] [Department of Physics A. Volta, Unita INFM and Sezione INFN, Via Bassi 6, I-27100 Pavia (Italy)

    1997-04-01

    {sup 63}Cu nuclear quadrupole resonance (NQR) relaxation measurements in La{sub 2}CuO{sub 4} doped Zn are used in order to investigate the temperature dependence of the in-plane magnetic correlation length {xi}{sub 2D} and the effects associated to spin vacancies in two dimensional quantum Heisenberg antiferromagnets (QHAF). The relaxation rates {ital T}{sub 1}{sup {minus}1} and {ital T}{sub 2}{sup {minus}1} have been related to the static generalized susceptibility {chi}({bold q},0) and to the decay rate {Gamma}{bold {sub q}} of the normal excitations. By using scaling arguments for {chi}({bold q},0) and {Gamma}{bold {sub q}}, the relaxation rates have been expressed in close form in terms of {xi}{sub 2D}{ital (x,T)} and its dependence on temperature and spin doping {ital x} thus extracted. The experimental findings are analyzed in light of the renormalized classical (RC) and quantum critical (QC) behaviors predicted for {xi}{sub 2D} by recent theories for {ital S}=1/2 HAF in square lattices. It is first shown that in pure La{sub 2}CuO{sub 4}, {xi}{sub 2D} is consistent with a RC regime up to about 900 K, with tendency toward the QC regime above. The spin vacancies reduce the N{acute e}el temperature according to the law {ital T{sub N}(x){approx}T{sub N}(0)(1{endash}3.5x)}. From the temperature dependence of {sup 63}Cu NQR relaxation rate {ital T}{sub 1}{sup {minus}1}, {ital T}{sub 2}{sup {minus}1} and from the composition dependence of {ital T{sub N}} it is consistently proved that the effect on {xi}{sub 2D} can be accounted for by the modification of the spin stiffness in a simple dilutionlike model, the system still remaining in the RC regime, at least for {ital T}{le}900 K. {copyright} {ital 1997 American Institute of Physics.}

  16. Remote sensing by nuclear quadrupole resonance

    Microsoft Academic Search

    Allen N. Garroway; Michael L. Buess; Joel B. Miller; Bryan H. Suits; Andrew D. Hibbs; Geoffrey A. Barrall; Robert Matthews; Lowell J. Burnett

    2001-01-01

    Detection of explosives has the flavor of those mathematical problems that are not invertible. It is easier to hide explosives than to find them. Many approaches have been proposed and executed for the remote detection of explosives, contraband materials, weapons of mass destruction, currency, etc. Most detection technologies suffer from a common problem: the features they look for, such as

  17. Heavy ion linear accelerator with high-frequency quadrupole focusing

    NASA Astrophysics Data System (ADS)

    Belyaev, O. K.; Budanov, Yu. A.; Zvonarev, I. A.; Ivanov, S. V.; Kudryavtsev, V. G.; Mazurov, E. V.; Mal'tsev, A. P.; Timofeev, A. A.; Kobets, V. V.; Meshkov, I. N.

    2013-12-01

    Based on results of works on the NICA/MPD (Joint Institute for Nuclear Research, Dubna) project, the possibility of designing a heavy ion linear accelerator with high-frequency quadrupole focusing both in the input part and in the main part of the accelerator is shown. Parameters of the linear 197Au31+ ion accelerator are presented. Special attention is paid to technical questions of calculating, designing, manufacturing, and tuning the accelerator.

  18. Distal and proximal ligand interactions in heme proteins: Correlations between C-O and Fe-C vibrational frequencies, oxygen-17 and carbon-13 nuclear magnetic resonance chemical shifts, and oxygen-17 nuclear quadrupole coupling constants in C sup 17 O- and sup 13 CO-labeled species

    SciTech Connect

    Ki Deok Park; Guo, K.; Adebodun, F.; Chiu, M.L.; Sligar, S.G.; Oldfield, E. (Univ. of Illinois, Urbana (United States))

    1991-03-05

    The authors have obtained the oxygen-17 nuclear magnetic resonance (NMR) spectra of a variety of C{sup 17}O-labeled heme proteins, including sperm whale (Physeter catodon) myoglobin, two synthetic sperm whale myoglobin mutants (His E7 {yields} Val E7; His E7 {yields} Phe E7), adult human hemoglobin, rabbit (Oryctolagus cuniculus) hemoglobin, horseradish (Cochlearia armoracia) peroxidase isoenzymes A and C, and Caldariomyces fumago chloroperoxidase, in some cases as a function of pH, and have determined their isotropic {sup 17}O NMR chemical shifts, {delta}{sub i}, and spin-lattice relaxation times, T{sub 1}. They have also obtained similar results on a picket fence prophyrin. The results show an excellent correlation between the infrared C-O vibrational frequencies, {nu}(C-O), and {delta}{sub i}, between {nu}(C-O) and the {sup 17}O nuclear quadrupole coupling constant, and as expected between e{sup 2}qQ/h and {delta}{sub i}. The results suggest the IR and NMR measurements reflect the same interaction, which is thought to be primarily the degree of {pi}-back-bonding from Fe d to CO {pi}* orbitals, as outlined previously.

  19. Sign-Selected Quadrupole Train

    SciTech Connect

    Bernstein, R.; NuTeV Collaboration

    1994-05-03

    The design of the Sign-Selected Quadrupole Train for E-815 (NuTeV) is set forth. The relevant physics requirements are explained. The optics of the beam are presented, along with an explanation of the proton dumping scheme. A discussion of rates and backgrounds follows, with special care given to backgrounds from scraping and obstructions. The relevant tolerances for beam construction are given and justified by simulations of the beamline. This leads to a discussion of the beam monitoring.

  20. A Crowdsourced nucleus: Understanding nuclear organization in terms of dynamically networked protein function

    PubMed Central

    Wood, Ashley M.; Garza-Gongora, Arturo G.; Kosak, Steven T.

    2014-01-01

    The spatial organization of the nucleus results in a compartmentalized structure that affects all aspects of nuclear function. This compartmentalization involves genome organization as well as the formation of nuclear bodies and plays a role in many functions, including gene regulation, genome stability, replication, and RNA processing. Here we review the recent findings associated with the spatial organization of the nucleus and reveal that a common theme for nuclear proteins is their ability to participate in a variety of functions and pathways. We consider this multiplicity of function in terms of Crowdsourcing, a recent phenomenon in the world of information technology, and suggest that this model provides a novel way to synthesize the many intersections between nuclear organization and function. PMID:24412853

  1. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1989-03-01

    Twenty-three laced permanent magnet quadrupole drift tube magnets have been constructed, tested, and installed in the SuperHILAC heavy ion linear accelerator at LBL, marking the first accelerator use of this new type of quadrupole. The magnets consist of conventional tape-wound quadrupole electromagnets, using iron pole-pieces, with permanent magnet material (samarium cobalt) inserted between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the individual quadrupole magnets in a drift tube linac is never reversed, we can take advantage of this asymmetrical saturation to provide about 20% greater focusing strength than is available with conventional quadrupoles, while replacing the vanadium permendur poletips with iron poletips. Comparisons between these magnets and conventional tape-wound quadrupoles will be presented. 3 refs., 5 figs.

  2. A Science-Based Approach to Understanding Waste Form Durability in Open and Closed Nuclear Fuel Cycles

    SciTech Connect

    Peters, M.T. [Applied Science and Technology, Argonne National Laboratory, 9700 South Cass Ave., Argonne, IL, 60439 (United States); Ewing, R.C. [Department of Geological Sciences, The University of Michigan, 2534 C.C. Little Bldg., 1100 N. University, Ann Arbor, MI, 48109-1005 (United States)

    2007-07-01

    There are two compelling reasons for understanding source term and near-field processes in a radioactive waste geologic repository. First, almost all of the radioactivity is initially in the waste form, mainly in the spent nuclear fuel (SNF) or nuclear waste glass. Second, over long periods, after the engineered barriers are degraded, the waste form is a primary control on the release of radioactivity. Thus, it is essential to know the physical and chemical state of the waste form after hundreds of thousands of years. The United States Department of Energy's Yucca Mountain Repository Program has initiated a long-term program to develop a basic understanding of the fundamental mechanisms of radionuclide release and a quantification of the release as repository conditions evolve over time. Specifically, the research program addresses four critical areas: a) SNF dissolution mechanisms and rates; b) formation and properties of U{sup 6+}- secondary phases; c) waste form-waste package interactions in the near-field; and d) integration of in-package chemical and physical processes. The ultimate goal is to integrate the scientific results into a larger scale model of source term and near-field processes. This integrated model will be used to provide a basis for understanding the behavior of the source term over long time periods (greater than 10{sup 5} years). Such a fundamental and integrated experimental and modeling approach to source term processes can also be readily applied to development of advanced waste forms as part of a closed nuclear fuel cycle. Specifically, a fundamental understanding of candidate waste form materials stability in high temperature/high radiation environments and near-field geochemical/hydrologic processes could enable development of advanced waste forms 'tailored' to specific geologic settings. (authors)

  3. Understanding and Managing Aging of Spent Nuclear Fuel and Facility Components in Wet Storage

    Microsoft Academic Search

    Johnson; A. Burton

    2007-01-01

    Storage of nuclear fuel after it has been discharged from reactors has become the leading spent fuel management option. Many storage facilities are being required to operate longer than originally anticipated. Aging is a term that has emerged to focus attention on the consequences of extended operation on systems, structures, and components that comprise the storage facilities. The key to

  4. Understanding the genetic structure of Symplocos laurina Wall. Populations using nuclear gene markers

    Microsoft Academic Search

    Sofia Banu; R. M. Bhagwat; N. Y. Kadoo; M. D. Lagu; V. S. Gupta

    2010-01-01

    To characterize the genetic diversity of present populations of Symplocos laurina, which grow in the montane forests in India, we analyzed the DNA sequences of a nuclear gene. Using the 881 bp sequence of cytosolic Glyceraldehyde-3-phosphate dehydrogenase gene, we detected 24 haplotypes among 195 individuals sampled from 14 populations. Two dominant haplotypes were distributed\\u000a over the entire range of this species

  5. Lighthill quadrupole radiation in supersonic propeller acoustics

    Microsoft Academic Search

    N. Peake; D. G. Crighton

    1991-01-01

    Sound generation by the Lighthill quadrupole is an important mechanism in the noise of supersonic and transonic propellers. Full numerical calculation of the quadrupole radiation, however, requires knowledge of the flow at all points exterior to the blades (involving transonic aerodynamics) and the evaluation of special functions. This paper describes how these difficulties may be largely avoided, using an asymptotic

  6. Electrostatic quadrupoles for heavy-ion fusion

    SciTech Connect

    Seidl, P.; Faltens, A.

    1993-05-01

    Voltage-holding data for three quadrupole electrode sizes and inter-electrode spacings are reported. The dependence of the breakdown voltage on system size and its influence on the optimum quadrupole size for beam transport in a multiple beam array are discussed.

  7. Peculiarities of phases of the WMAP quadrupole

    E-print Network

    Pavel D. Naselsky; Oleg V. Verkhodanov

    2008-03-13

    We present the analysis on the quadrupole phases of the Internal Linear Combination map, ILC(I) and (III) derived by the WMAP team (1 and 3-year data release). This approach allows us to see the global trend of non-Gaussianity of the quadrupoles for the ILC(III) map through phase correlations with the foregrounds. Significant phase correlations is found in between the ILC(III) quadrupole and the WMAP foregrounds phases for K-W band: the phases of the ILC(III) quadrupole xi_{2,1}, xi_{2,2} and those of the foregrounds at K-W bands Phi_{2,1}, Phi_{2,2} display significant symmetry: xi_{2,1}+Phi_{2,1} ~= xi_{2,2}+Phi_{2,2}, which is a strong indication that the morphology of the ILC(III) quadrupole is mere reflection of that the foreground quadrupole through coupling. To clarify this issue we exploit the symmetry of the CMB power, which is invariant under permutation of the index m=12. By simple rotation of the ILC(III) phases with the same angle we reach the phases of foreground quadrupole. We discuss possible sources of phase correlation and come to the conclusion that the phases of the ILC(III) quadrupole reflect most likely systematic effects such as changing of the gain factor for the 3-year data release with respect to the 1-year, rather than manifestation of the primordial non-Gaussianity.

  8. Understanding ploidy complex and geographic origin of the Buchloe dactyloides genome using cytoplasmic and nuclear marker systems.

    PubMed

    Budak, H; Shearman, R C; Gulsen, O; Dweikat, I

    2005-11-01

    Characterizing and inferring the buffalograss [Buchloe dactyloides (Nutt.) Engelm.] genome organization and its relationship to geographic distribution are among the purposes of the buffalograss breeding and genetics program. This buffalograss study was initiated to: (1) better understand the buffalograss ploidy complex using various marker systems representing nuclear and organelle genomes; (2) determine whether the geographic distribution was related to nuclear and organelle genome variation; and (3) compare the genetic structure of accessions with different ploidy levels. The 20 buffalograss genotypes (15 individuals from each genotype) that were studied included diploid, tetraploid, pentaploid, and hexaploid using nuclear (intersimple sequence repeat (ISSRs), simple sequence repeat (SSRs), sequence related amplified polymorphism (SRAPs), and random amplified polymorphic DNA (RAPDs)) and cytoplasmic markers (mtDNA and cpDNA). There was a significant correlation between the ploidy levels and number of alleles detected using nuclear DNA (ISSR, SSR, and SRAP, r = 0.39, 0.39, and 0.41, P<0.05, respectively), but no significant correlation was detected when mitochondrial (r = 0.17, P<0.05) and chloroplast (r = 0.11, P < 0.05) DNA data sets were used. The geographic distribution of buffalograss was not correlated with nuclear and organelle genome variation for the genotypes studied. Among the total populations sampled, regression analysis indicated that geographic distance could not explain genetic differences between accessions. However, genetic distances of those populations from the southern portion of buffalograss adaptation were significantly correlated with geographic distance (r= 0.48, P<0.05). This result supports the hypothesis that genetic relationship among buffalograss populations cannot be estimated based only on geographic proximity. PMID:16208501

  9. Mechanistic understanding of irradiation-induced corrosion of zirconium alloys in nuclear power plants: Stimuli, status, and outlook

    SciTech Connect

    Johnson, A.B. Jr.; Ishigure, K.; Nechaev, A.F.; Reznichenko, E.A.; Cox, B.; Lemaignan, C.; Petrik, N.G.

    1990-05-01

    Failures in the basic materials used in nuclear power plants continue to be costly and insidious, despite increasing industry vigilance to catch failures before they degrade safety. For instance, the overall costs to the US industry from materials problems could amount to as much as $10 billion annually. Moreover, estimates indicate that the cost of a pipe failure in a nuclear plant is one hundred times greater than the cost of a similar failure in a coal-fired plant. There are important practical stimuli and much scope for further understanding of the effects of irradiation on Zr-alloys (and other materials used in nuclear installations) by careful experimentation. Moreover, these studies need to address the effect of irradiation on all components of heterogeneous systems: the metal, the oxide and the environment, and especially those processes recurring at the interphases between these components. The present paper is aimed at providing specialists with some systematic information on the subject and with important considerations on the key items for further experimentation.

  10. Use of computer algebra for the study of quadrupole spin systems

    NASA Astrophysics Data System (ADS)

    Isbister, D. J.; Krishnan, Mangala S.; Sanctuary, B. C.

    1995-12-01

    Analytical computation of the effect of radiofrequency pulses and free evolution between pulses are studied in a spin system dominated by the nuclear electric quadrupole interaction using 'symbolic computer algebra'. The program MAPLE is used to compute spin density matrices for single spin systems with spin magnitude I = 1, 3/2, 2 and 5/2. In all cases except I = 5/2, the pure nuclear electric quadrupole Hamiltonian with arbitrary asymmetry parameter ? is used to obtain results for a single pulse and an evolution period following the pulse. In the spin 5/2 system ? is set to zero. The calculations are done using a simple matrix representation of the density operator and the Baker-Campbell-Hausdorff formula. In addition, the validity of dropping non-secular (i.e., time-dependent) terms from the Hamiltonian for the pulse in the quadrupole interaction frame is examined for the spin 1 case using a truncated Magnus expansion.

  11. Use of First Order Reversal Curve Measurements to Understand Barkhausen Noise Emission in Nuclear Steel

    SciTech Connect

    McCloy, John S.; Ramuhalli, Pradeep; Henager, Charles H.

    2013-02-25

    A prototypical ferritic/martensitic alloy, HT-9, of interest to the nuclear materials community was investigated for microstructure effects on Barkhausen noise emission and first-order reversal curve (FORC) analysis for three different heat-treated samples. It was observed that Barkhausen noise emission and reversible component of magnetization, computed from the FORC data, decreased with increasing measured mechanical hardness. The results are discussed in terms of the use of magnetic signatures for use in nondestructive interrogation of radiation damage and other microstructural changes in ferritic/martensitic alloys. FORC analysis is shown to be particularly useful for detailed characterization of defect density and pinning, which can be correlated to bulk non-destructive evaluation field measurements such as Barkhausen noise emission.

  12. Estimation of dipole-quadrupole dispersion energies.

    NASA Technical Reports Server (NTRS)

    Alvarez-Rizzatti, M.; Mason, E. A.

    1973-01-01

    The calculation of the dipole-quadrupole dispersion coefficient is discussed through a perturbation and a variation method. Accurate combination rules are obtained from both methods, one new and one already known. Further approximations permit computations in terms of accessible parameters. Values are calculated for the interactions of atomic pairs formed from hydrogen, alkali, and rare-gas atoms. A new relation giving the dipole-quadrupole coefficient in terms of the dipole-dipole coefficient and the dipole and quadrupole polarizabilities seems accurate, but needs further testing.

  13. Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Andrew, E. R.

    2009-06-01

    Author's preface; 1. Introduction; 2. Basic theory; 3. Experimental methods; 4. Measurement of nuclear properties and general physical applications; 5. Nuclear magnetic resonance in liquids and gases; 6. Nuclear magnetic resonance in non-metallic solids; 7. Nuclear magnetic resonance in metals; 8. Quadrupole effects; Appendices 1-6; Glossary of symbols; Bibliography and author index; Subject index.

  14. Toward Understanding the Effect of Nuclear Waste Glass Composition on Sulfur Solubility

    DOE PAGESBeta

    Vienna, John D.; Kim, Dong-Sang; Muller, I. S.; Kruger, Albert A.; Piepel, Gregory F.

    2014-10-01

    The concentration of sulfur in nuclear waste glass melter feed must be maintained below the point where salt accumulates on the melt surface. The allowable concentrations may range from 0.37 to over 2.05 weight percent (of SO3 on a calcined oxide basis) depending on the composition of the melter feed and processing conditions. If the amount of sulfur exceeds the melt tolerance level, a molten salt will accumulate, which may upset melter operations and potentially shorten the useful life of the melter. At the Hanford site, relatively conservative limits have been placed on sulfur loading in melter feed, which inmore »turn significantly increases the amount of glass that will be produced. Crucible-scale sulfur solubility data and scaled melter sulfur tolerance data have been collected on simulated Hanford waste glasses over the last 15 years. These data were compiled and analyzed. A model was developed to predict the solubility of SO3 in glass based on 252 simulated Hanford low-activity waste (LAW) glass compositions. This model represents the data well, accounting for over 85% of the variation in data, and was well validated. The model was also found to accurately predict the tolerance for sulfur in melter feed for 13 scaled melter tests of simulated LAW glasses. The model can be used to help estimate glass volumes and make informed decisions on process options. The model also gives quantitative estimates of component concentration effects on sulfur solubility. The components that most increase sulfur solubility are Li2O > V2O5> CaO ? P2O5 > Na2O ? B2O3 > K2O. The components that most decrease sulfur solubility are Cl > Cr2O3 > Al2O3 > ZrO2 ? SnO2 > Others ? SiO2. The order of component effects is similar to previous literature data, in most cases.« less

  15. Understanding Fuel Magnetization and Mix Using Secondary Nuclear Reactions in Magneto-Inertial Fusion

    NASA Astrophysics Data System (ADS)

    Schmit, P. F.; Knapp, P. F.; Hansen, S. B.; Gomez, M. R.; Hahn, K. D.; Sinars, D. B.; Peterson, K. J.; Slutz, S. A.; Sefkow, A. B.; Awe, T. J.; Harding, E.; Jennings, C. A.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Geissel, M.; Harvey-Thompson, A. J.; Herrmann, M. C.; Hess, M. H.; Johns, O.; Lamppa, D. C.; Martin, M. R.; McBride, R. D.; Porter, J. L.; Robertson, G. K.; Rochau, G. A.; Rovang, D. C.; Ruiz, C. L.; Savage, M. E.; Smith, I. C.; Stygar, W. A.; Vesey, R. A.

    2014-10-01

    Magnetizing the fuel in inertial confinement fusion relaxes ignition requirements by reducing thermal conductivity and changing the physics of burn product confinement. Diagnosing the level of fuel magnetization during burn is critical to understanding target performance in magneto-inertial fusion (MIF) implosions. In pure deuterium fusion plasma, 1.01 MeV tritons are emitted during deuterium-deuterium fusion and can undergo secondary deuterium-tritium reactions before exiting the fuel. Increasing the fuel magnetization elongates the path lengths through the fuel of some of the tritons, enhancing their probability of reaction. Based on this feature, a method to diagnose fuel magnetization using the ratio of overall deuterium-tritium to deuterium-deuterium neutron yields is developed. Analysis of anisotropies in the secondary neutron energy spectra further constrain the measurement. Secondary reactions also are shown to provide an upper bound for the volumetric fuel-pusher mix in MIF. The analysis is applied to recent MIF experiments [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014), 10.1103/PhysRevLett.113.155003] on the Z Pulsed Power Facility, indicating that significant magnetic confinement of charged burn products was achieved and suggesting a relatively low-mix environment. Both of these are essential features of future ignition-scale MIF designs.

  16. Understanding fuel magnetization and mix using secondary nuclear reactions in magneto-inertial fusion.

    PubMed

    Schmit, P F; Knapp, P F; Hansen, S B; Gomez, M R; Hahn, K D; Sinars, D B; Peterson, K J; Slutz, S A; Sefkow, A B; Awe, T J; Harding, E; Jennings, C A; Chandler, G A; Cooper, G W; Cuneo, M E; Geissel, M; Harvey-Thompson, A J; Herrmann, M C; Hess, M H; Johns, O; Lamppa, D C; Martin, M R; McBride, R D; Porter, J L; Robertson, G K; Rochau, G A; Rovang, D C; Ruiz, C L; Savage, M E; Smith, I C; Stygar, W A; Vesey, R A

    2014-10-10

    Magnetizing the fuel in inertial confinement fusion relaxes ignition requirements by reducing thermal conductivity and changing the physics of burn product confinement. Diagnosing the level of fuel magnetization during burn is critical to understanding target performance in magneto-inertial fusion (MIF) implosions. In pure deuterium fusion plasma, 1.01 MeV tritons are emitted during deuterium-deuterium fusion and can undergo secondary deuterium-tritium reactions before exiting the fuel. Increasing the fuel magnetization elongates the path lengths through the fuel of some of the tritons, enhancing their probability of reaction. Based on this feature, a method to diagnose fuel magnetization using the ratio of overall deuterium-tritium to deuterium-deuterium neutron yields is developed. Analysis of anisotropies in the secondary neutron energy spectra further constrain the measurement. Secondary reactions also are shown to provide an upper bound for the volumetric fuel-pusher mix in MIF. The analysis is applied to recent MIF experiments [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] on the Z Pulsed Power Facility, indicating that significant magnetic confinement of charged burn products was achieved and suggesting a relatively low-mix environment. Both of these are essential features of future ignition-scale MIF designs. PMID:25375715

  17. Klystron having electrostatic quadrupole focusing arrangement

    DOEpatents

    Maschke, A.W.

    1983-08-30

    A klystron includes a source for emitting at least one electron beam, and an accelerator for accelerating the beam in a given direction through a number of drift tube sections successively aligned relative to one another in the direction of the beam. A number of electrostatic quadrupole arrays are successively aligned relative to one another along at least one of the drift tube sections in the beam direction for focusing the electron beam. Each of the electrostatic quadrupole arrays forms a different quadrupole for each electron beam. Two or more electron beams can be maintained in parallel relationship by the quadrupole arrays, thereby enabling space charge limitations encountered with conventional single beam klystrons to be overcome. 4 figs.

  18. Klystron having electrostatic quadrupole focusing arrangement

    DOEpatents

    Maschke, Alfred W. (East Moriches, NY)

    1983-08-30

    A klystron includes a source for emitting at least one electron beam, and an accelerator for accelarating the beam in a given direction through a number of drift tube sections successively aligned relative to one another in the direction of the beam. A number of electrostatic quadrupole arrays are successively aligned relative to one another along at least one of the drift tube sections in the beam direction for focusing the electron beam. Each of the electrostatic quadrupole arrays forms a different quadrupole for each electron beam. Two or more electron beams can be maintained in parallel relationship by the quadrupole arrays, thereby enabling space charge limitations encountered with conventional single beam klystrons to be overcome.

  19. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, Roman O. (Mountain View, CA)

    1997-01-01

    Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.

  20. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1998-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  1. Miniature quadrupole mass spectrometer array

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael H. (Inventor); Orient, Otto J. (Inventor)

    1997-01-01

    The present invention provides a minature quadrupole mass spectrometer array for the separation of ions, comprising a first pair of parallel, planar, nonmagnetic conducting rods each having an axis of symmetry, a second pair of planar, nonmagnetic conducting rods each having an axis of symmetry parallel to said first pair of rods and disposed such that a line perpendicular to each of said first axes of symmetry and a line perpendicular to each of said second axes of symmetry bisect each other and form a generally 90 degree angle. A nonconductive top positioning plate is positioned generally perpendicular to the first and second pairs of rods and has an aperture for ion entrance along an axis equidistant from each axis of symmetry of each of the parallel rods, a nonconductive bottom positioning plate is generally parallel to the top positioning plate and has an aperture for ion exit centered on an axis equidistant from each axis of symmetry of each of the parallel rods, means for maintaining a direct current voltage between the first and second pairs of rods, and means for applying a radio frequency voltage to the first and second pairs of rods.

  2. Transport properties of a discrete helical electrostatic quadrupole

    SciTech Connect

    Meitzler, C.R.; Antes, K.; Datte, P.; Huson, F.R. (Texas Accelerator Center, The Woodlands, TX (United States)); Xiu, L. (Houston Univ., TX (United States). Inst. for Beam Particle Dynamics)

    1991-01-01

    The helical electrostatic quadrupole (HESQ) lens has been proposed as a low energy beam transport system which permits intense H{sup {minus}} beams to be focused into an RFQ without seriously increasing the beam's emittance. A stepwise continuous HESQ lens has been constructed, and preliminary tests have shown that the structure does provide focusing. In order to understand the transport properties of this device, further detailed studies have been performed. Emittances were measured 3.5 cm from the end of the HESQ at two different voltages on the HESQ electrodes. A comparison of these experimental results with a linear model of the HESQ beam transport is made. 4 refs., 5 figs.

  3. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1988-10-01

    A laced permanent magnet quadrupole drift tube magnet has been constructed for a proof-of-principle test. The magnet is a conventional tape-wound quadrupole electromagnet, using iron pole- pieces, with the addition of permanent magnet material (neodymium iron) between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the quadrupole magnets in a drift tube linac is not reversed we can take advantage of this asymmetrical saturation to provide greater focusing strength. The magnet configuration has been optimized and the vanadium permendur poles needed in a conventional quadrupole have been replaced with iron poles. The use of permanent magnet material has allowed us to increase the focusing strength of the magnet by about 20% over that of a conventional tape-wound quadrupole. Comparisons will be made between this magnet and the conventional tape-wound quadrupole. 3 refs., 5 figs.

  4. Understanding public responses to chemical, biological, radiological and nuclear incidents--driving factors, emerging themes and research gaps.

    PubMed

    Krieger, Kristian; Amlôt, Richard; Rogers, M Brooke

    2014-11-01

    This paper discusses the management of public responses to incidents involving chemical, biological, radiological and nuclear materials (CBRN). Given the extraordinary technical and operational challenges of a response to a CBRN release including, but not limited to, hazard detection and identification, casualty decontamination and multi-agency co-ordination, it is not surprising that public psychological and behavioural responses to such incidents have received limited attention by scholars and practitioners alike. As a result, a lack of understanding about the role of the public in effective emergency response constitutes a major gap in research and practice. This limitation must be addressed as a CBRN release has the potential to have wide-reaching psychological and behavioural impacts which, in turn, impact upon public morbidity and mortality rates. This paper addresses a number of key issues: why public responses matter; how responses have been conceptualised by practitioners; what factors have been identified as influencing public responses to a CBRN release and similar extreme events, and what further analysis is needed in order to generate a better understanding of public responses to inform the management of public responses to a CBRN release. PMID:24856235

  5. Understanding the Nuclear Gas Dispersion in Early-Type Galaxies in the Context of Black Hole Demographics

    NASA Astrophysics Data System (ADS)

    Verdoes Kleijn, Gijs A.; van der Marel, Roeland P.; Noel-Storr, Jacob

    2006-04-01

    The majority of nearby early-type galaxies contain detectable amounts of emission-line gas at their centers. The nuclear gas kinematics form a valuable diagnostic of the central black hole (BH) mass. Here we analyze and model Hubble Space Telescope STIS observations of a sample of 27 galaxies; 16 Fanaroff-Riley Type I radio galaxies and 11 (more) normal early-type galaxies. We focus here on what can be learned from the nuclear velocity dispersion (line width) of the gas as a complement to the many studies dealing with gas rotation velocities. We find that the dispersion in a STIS aperture of ~0.1"-0.2" generally exceeds the large-scale stellar velocity dispersion of the galaxy. This is qualitatively consistent with the presence of central BHs but raises the questions of whether the excess gas dispersion is of gravitational or nongravitational origin and whether the implied BH masses are consistent with our current understanding of BH demography (as predicted by the M-? relation between BH mass and stellar velocity dispersion). To address this we construct purely gravitational axisymmetric dynamical models for the gas, both thin-disk models and models with more general axis ratios and velocity anisotropies. For the normal galaxies the nuclear gas dispersions are adequately reproduced assuming disks around the BHs with masses that follow the M-? relation. In contrast, the gas dispersions observed for the radio galaxies generally exceed those predicted by any of the models. We attribute this to the presence of nongravitational motions in the gas that are similar to or larger than the gravitational motions. The nongravitational motions are presumably driven by the active galactic nucleus (AGN), but we do not find a relation between the radiative output of the AGN and the nongravitational dispersion. Given the uncertainties about the dynamical state of the gas, it is not possible to uniquely determine the BH mass for each galaxy from its nuclear gas dispersion. However, for the sample as a whole the observed dispersions do not provide evidence for significant deviations from the M-? relation. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

  6. Production of 62Zn radioactive nuclear beam and on-line PAC investigation of quadrupole interaction in nano-magnetic material Fe73.5Cu1Nb3Si13.5B9

    NASA Astrophysics Data System (ADS)

    Zuo, Yi; Zheng, Yongnan; Xu, Yongjun; Cui, Baoqun; Li, Liqiang; Ma, Yingjun; Ping, Fan; Yuan, Daqing; Gao, Shuang; Zhu, Shengyun

    2013-05-01

    An Isotope Separator On-Line (ISOL), dedicated to on-line perturbed angular correlation (PAC) and positron annihilation spectroscopy (PAS), has been constructed at CIAE based on the HI-13 tandem accelerator, and a 30 keV radioactive beam of 62Zn with intensity of 2 ×107/s produced by it. Using the 62Zn radioactive beam the investigation of the nano-crystalline soft magnetic Fe73.5Cu1Nb3Si13.5B9 materials has been fulfiled for the first time by the on-line time differential PAC technique. Two quadrupole interaction frequencies ? 01 ( = 440 Mrad/s) and ? 02 ( = 90 Mrad/s) were gained, indicating there are two implantation sites of 62Zn. The frequency ? 02 shows a fluctuation of the crystal lattice constants and proves the characteristic distribution model of nano-crystalline grain boundary. The frequency ? 01 demonstrates that the implanted 62Zn occupies the site of the ordered grain core. The fractions of ? 01 and ? 02 are f01 = 38 % and f02 = 62 %, respectively.

  7. Dipole gravity waves from unbound quadrupoles

    E-print Network

    Franklin Felber

    2010-06-10

    Dipole gravitational disturbances from gravitationally unbound mass quadrupoles propagate to the radiation zone with signal strength at least of quadrupole order if the quadrupoles are nonrelativistic, and of dipole order if relativistic. Angular distributions of parallel-polarized and transverse-polarized dipole power in the radiation zone are calculated for simple unbound quadrupoles, like a linear-oscillator/stress-wave pair and a particle storage ring. Laboratory tests of general relativity through measurements of dipole gravity waves in the source region are proposed. A NASA G2 flywheel module with a modified rotor can produce a post-Newtonian dc bias signal at a gradiometer up to 1 mE. At peak luminosity, the repulsive dipole impulses of proton bunches at the LHC can produce an rms velocity of a high-Q detector surface up to 4 micron/s. Far outside the source region, Newtonian lunar dipole gravity waves can produce a 1-cm displacement signal at LISA. Dipole signal strengths of astrophysical events involving unbound quadrupoles, like near collisions and neutron star kicks in core-collapse supernovae, are estimated.

  8. Microfluidic quadrupole and floating concentration gradient

    PubMed Central

    Qasaimeh, Mohammad A.; Gervais, Thomas; Juncker, David

    2014-01-01

    The concept of fluidic multipoles, in analogy to electrostatics, has long been known as a particular class of solutions of the Navier-Stokes equation in potential flows, however, experimental observations of fluidic multipoles and of their characteristics have not been reported yet. Here we present a two-dimensional microfluidic quadrupole and a theoretical analysis consistent with the experimental observations. The microfluidic quadrupole was formed by simultaneously injecting and aspirating fluids from two pairs of opposing apertures in a narrow gap formed between a microfluidic probe and a substrate. A stagnation point was formed at the center of the microfluidic quadrupole, and its position could be rapidly adjusted hydrodynamically. Following the injection of a solute through one of the poles, a stationary, tunable, and movable – i.e. “floating” – concentration gradient was formed at the stagnation point. Our results lay the foundation for future combined experimental and theoretical exploration of microfluidic planar multipoles including convective-diffusive phenomena. PMID:21897375

  9. T1? in Quadrupole-Perturbed NMR

    NASA Astrophysics Data System (ADS)

    Seliger, J.

    Spin-lattice relaxation time in the rotating frame, T1?, is calculated in quadrupole-perturbed NMR in the weak collision limit. It is assumed that the RF magnetic field excites only a single transition in the quadrupole-perturbed NMR spectrum. The results of the calculation show that T1?, associated with the central ( {1}/{2}?- {1}/{2}) transition in quadrupole-perturbed NMR of half-integer spin nuclei does not reflect the low-frequency fluctuations of the electric field-gradient tenser. On the other hand, the low-frequency fluctuations of the electric held-gradient tenser give the largest contribution to T1? when measured on the outer[± I?±( I-1)] satellite transitions.

  10. Classical toy models for the monopole shift and the quadrupole shift.

    PubMed

    Rose, Katrin; Cottenier, Stefaan

    2012-08-28

    The penetration of s- and p(1/2)-electrons into the atomic nucleus leads to a variety of observable effects. The presence of s-electrons inside the nucleus gives rise to the isotope shift in atomic spectroscopy, and to the isomer shift in Mössbauer spectroscopy. Both well-known phenomena are manifestations of the more general monopole shift. In a recent paper (Koch et al., Phys. Rev. A, 2010, 81, 032507), we discussed the existence of the formally analogous quadrupole shift: a tensor correction to the electric quadrupole interaction due to the penetration of relativistic p(1/2)-electrons into the nucleus. The quadrupole shift is predicted to be observable by high-accuracy molecular spectroscopy on a set of 4 molecules (the quadrupole anomaly). The simple physics behind all these related phenomena is easily obscured by an elaborate mathematical formalism that is required for their derivation: a multipole expansion in combination with perturbation theory, invoking quantum physics and ideally relativity. In the present paper, we take a totally different approach. We consider three classical 'toy models' that can be solved by elementary calculus, and that nevertheless contain all essential physics of the monopole and quadrupole shifts. We hope that this intuitive (yet exact) analysis will increase the understanding about multipole shift phenomena in a broader community. PMID:22782015

  11. The large quadrupole of water molecules

    PubMed Central

    Niu, Shuqiang; Tan, Ming-Liang; Ichiye, Toshiko

    2011-01-01

    Many quantum mechanical calculations indicate water molecules in the gas and liquid phase have much larger quadrupole moments than any of the common site models of water for computer simulations. Here, comparisons of multipoles from quantum mechanical?molecular mechanical (QM?MM) calculations at the MP2?aug-cc-pVQZ level on a B3LYP?aug-cc-pVQZ level geometry of a waterlike cluster and from various site models show that the increased square planar quadrupole can be attributed to the p-orbital character perpendicular to the molecular plane of the highest occupied molecular orbital as well as a slight shift of negative charge toward the hydrogens. The common site models do not account for the p-orbital type electron density and fitting partial charges of TIP4P- or TIP5P-type models to the QM?MM dipole and quadrupole give unreasonable higher moments. Furthermore, six partial charge sites are necessary to account reasonably for the large quadrupole, and polarizable site models will not remedy the problem unless they account for the p-orbital in the gas phase since the QM calculations show it is present there too. On the other hand, multipole models by definition can use the correct multipoles and the electrostatic potential from the QM?MM multipoles is much closer than that from the site models to the potential from the QM?MM electron density. Finally, Monte Carlo simulations show that increasing the quadrupole in the soft-sticky dipole-quadrupole-octupole multipole model gives radial distribution functions that are in good agreement with experiment. PMID:21476758

  12. Magnetic Measurement Results of the LCLS Undulator Quadrupoles

    SciTech Connect

    Anderson, Scott; Caban, Keith; Nuhn, Heinz-Dieter; Reese, Ed; Wolf, Zachary; /SLAC; ,

    2011-08-18

    This note details the magnetic measurements and the magnetic center fiducializations that were performed on all of the thirty-six LCLS undulator quadrupoles. Temperature rise, standardization reproducibility, vacuum chamber effects and magnetic center reproducibility measurements are also presented. The Linac Coherent Light Source (LCLS) undulator beam line has 33 girders, each with a LCLS undulator quadrupole which focuses and steers the beam through the beam line. Each quadrupole has main quadrupole coils, as well as separate horizontal and vertical trim coils. Thirty-six quadrupoles, thirty-three installed and three spares were, manufactured for the LCLS undulator system and all were measured to confirm that they met requirement specifications for integrated gradient, harmonics and for magnetic center shifts after current changes. The horizontal and vertical dipole trims of each quadrupole were similarly characterized. Each quadrupole was also fiducialized to its magnetic center. All characterizing measurements on the undulator quads were performed with their mirror plates on and after a standardization of three cycles from -6 to +6 to -6 amps. Since the undulator quadrupoles could be used as a focusing or defocusing magnet depending on their location, all quadrupoles were characterized as focusing and as defocusing quadrupoles. A subset of the undulator quadrupoles were used to verify that the undulator quadrupole design met specifications for temperature rise, standardization reproducibility and magnetic center reproducibility after splitting. The effects of the mirror plates on the undulator quadrupoles were also measured.

  13. Accelerator Magnets:. Dipole, Quadrupole and Sextupole

    NASA Astrophysics Data System (ADS)

    Hwang, C. S.

    2004-02-01

    The main characteristics of the magnet design and performance of lattice magnets including dipole, quadrupole, and sextupole magnets, will be presented. The design and construction constraints of the conventional, steel iron yoke, and the direct-current magnets are also discussed. The equations of the ideal pole shapes of the dipole, quadrupole, and sextupole, are used to design the magnets. Several two- or three-dimensional calculation codes are introduced to simulate the magnets. Moreover, a brief description of the injection magnets is also presented. Finally, field measurement and mapping methods are introduced and the results from field measurements by means of a Hall probe are discussed.

  14. SKEW QUADRUPOLE FOCUSING LATTICES AND APPLICATIONS.

    SciTech Connect

    PARKER,B.

    2001-06-18

    In this paper we revisit using skew quadrupole fields in place of traditional normal upright quadrupole fields to make beam focusing structures. We illustrate by example skew lattice decoupling, dispersion suppression and chromatic correction using the neutrino factory Study-II muon storage ring design. Ongoing BNL investigation of flat coil magnet structures that allow building a very compact muon storage ring arc and other flat coil configurations that might bring significant magnet cost reduction to a VLHC motivate our study of skew focusing.

  15. 76 FR 31997 - Final Memorandum of Understanding Between the U.S. Nuclear Regulatory Commission and the U.S...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-02

    ...Between the U.S. Nuclear Regulatory Commission and the U.S. Department of Homeland Security on Chemical Facility Anti-Terrorism Standards AGENCY: Nuclear Regulatory Commission. ACTION: Notice of...

  16. Giant Quadrupole-Resonance in Ni Isotopes 

    E-print Network

    Youngblood, David H.; Lui, YW; Garg, U.; Peterson, R. J.

    1992-01-01

    Inelastic scattering of 129 MeV alpha particles has been used to excite the giant quadrupole resonance in Ni-58, Ni-60, Ni-62, Ni-64. The resonance was found to exhaust 58 +/- 12%, 76 +/- 14%, 78 +/- 14%, and 90 +/-16% of the E2 energy-weighted sum...

  17. LHC INTERACTION REGION QUADRUPOLE CRYOSTAT DESIGN

    Microsoft Academic Search

    T. H. Nicol; Ch. Darve; Y. Huang; T. M. Page

    The cryostat of a Large Hadron Collider (LHC) Interaction Region (IR) quadrupole magnet consists of all components of the inner triplet except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, to house all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It

  18. LHC interaction region quadrupole cryostat design

    Microsoft Academic Search

    T. H. Nicol; Ch. Darve; Y. Huang; T. M. Page

    2002-01-01

    The cryostat of a Large Hadron Collider (LHC) Interaction Region (IR) quadrupole magnet consists of all components of the inner triplet except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, to house all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It

  19. Hydrogen isotope analysis by quadrupole mass spectrometry

    Microsoft Academic Search

    R. E. Ellefson; W. E. Moddeman; H. F. Dylla

    1981-01-01

    The analysis of isotopes of hydrogen (H, D, T) and helium (³He, He) and selected impurities using a quadrupole mass spectrometer (QMS) has been investigated as a method of measuring the purity of tritium gas for injection into the Tokamak Fusion Test Reactor (TFTR). A QMS was used at low resolution, m\\/..delta..m < 150, for quantifying impurities from m\\/q =

  20. Closed orbit response to quadrupole strength variation

    SciTech Connect

    Wolski, Andrzej; Zimmermann, Frank

    2004-01-20

    We derive two formulae relating the variation in closed orbit in a storage ring to variations in quadrupole strength, neglecting nonlinear and dispersive effects. These formulae correct results previously reported [1,2,3]. We compare the results of the formulae applied to the ATF with simulations using MAD, and consider their application to beam-based alignment.

  1. Hybrid Rare Earih Quadrupole Drift Tube Magnets

    Microsoft Academic Search

    K. Halbach; M. I. Green; R. MacGill; J. Tanabe; J. Milburn

    1985-01-01

    A prototype quadrupole permanent magnet with adjustable field strength has been constructed and tested. The magnet consists of iron pole pieces to provide the required field shape along with rare earth permanent magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field by rotating the outer rings consisting of permanent

  2. Hybrid Rare Earth Quadrupole Drift Tube Magnets

    Microsoft Academic Search

    K. Halbach; B. Feinberg; M. I. Green; R. MacGill; J. Milburn; J. Tanabe

    1985-01-01

    A prototype quadrupole permanent magnet with adjustable field strength has been constructed and tested. The magnet consists of iron pole pieces to provide the required field shape along with rare earth permanent magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field by rotating the outer rings consisting of permanent

  3. Thermal analysis of SC quadrupoles in accelerator interaction regions

    SciTech Connect

    Novitski, Igor; Zlobin, Alexander V.; /Fermilab

    2006-09-01

    This paper presents results of a thermal analysis and operation margin calculation performed for NbTi and Nb{sub 3}Sn low-beta quadrupoles in collider interaction regions. Results of the thermal analysis for NbTi quadrupoles are compared with the relevant experimental data. An approach to quench limit measurements for Nb{sub 3}Sn quadrupoles is discussed.

  4. Covariant Spectator Theory of np scattering: Deuteron Quadrupole Moment

    DOE PAGESBeta

    Gross, Franz

    2015-01-01

    The deuteron quadrupole moment is calculated using two CST model wave functions obtained from the 2007 high precision fits to np scattering data. Included in the calculation are a new class of isoscalar np interaction currents automatically generated by the nuclear force model used in these fits. The prediction for model WJC-1, with larger relativistic P-state components, is 2.5% smaller that the experiential result, in common with the inability of models prior to 2014 to predict this important quantity. However, model WJC-2, with very small P-state components, gives agreement to better than 1%, similar to the results obtained recently frommore »chiral effect field theory predictions to order next-to-next-to-next-to-leading order.« less

  5. Covariant Spectator Theory of np scattering: Deuteron Quadrupole Moment

    DOE PAGESBeta

    Gross, Franz

    2015-01-01

    The deuteron quadrupole moment is calculated using two CST model wave functions obtained from the 2007 high precision fits to np scattering data. Included in the calculation are a new class of isoscalar np interaction currents automatically generated by the nuclear force model used in these fits. The prediction for model WJC-1, with larger relativistic P-state components, is 2.5% smaller that the experiential result, in common with the inability of models prior to 2014 to predict this important quantity. However, model WJC-2, with very small P-state components, gives agreement to better than 1%, similar to the results obtained recently from chiral effect field theory predictions to order next-to-next-to-next-to-leading order.

  6. Global study of quadrupole correlation effects

    SciTech Connect

    Bender, M. [Department of Physics and Institute for Nuclear Theory, Box 351560, University of Washington, Seattle, Washington 98195 (United States); Physics Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439 (United States); National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Bertsch, G.F. [Department of Physics and Institute for Nuclear Theory, Box 351560, University of Washington, Seattle, Washington 98195 (United States); Heenen, P.-H. [Service de Physique Nucleaire Theorique, Universite Libre de Bruxelles, CP 229, B-1050 Brussels (Belgium)

    2006-03-15

    We discuss the systematics of ground-state quadrupole correlations of binding energies and mean-square charge radii for all even-even nuclei, from {sup 16}O up to the superheavies, for which data are available. To that aim we calculate their correlated J=0 ground state by means of the angular-momentum and particle-number projected generator coordinate method, using the axial mass quadrupole moment as the generator coordinate and self-consistent mean-field states restricted only by axial, parity, and time-reversal symmetries. The calculation is performed within the framework of a nonrelativistic self-consistent mean-field model by use of the same Skyrme interaction SLy4 and to a density-dependent pairing force to generate the mean-field configurations and to mix them. These are the main conclusions of our study: (i) The quadrupole correlation energy varies between a few 100 keV and about 5.5 MeV. It is affected by shell closures, but varies only slightly with mass and asymmetry. (ii) Projection on angular momentum J=0 provides the major part of the energy gain of up to about 4 MeV; all nuclei in the study, including doubly magic ones, gain energy by deformation. (iii) The mixing of projected states with different intrinsic axial deformations adds a few 100 keV up to 1.5 MeV to the correlation energy. (iv) Typically nuclei below mass A{<=}60 have a larger correlation energy than static deformation energy whereas the heavier deformed nuclei have larger static deformation energy than correlation energy. (v) Inclusion of the quadrupole correlation energy improves the description of mass systematics, particularly around shell closures, and of differential quantities, namely two-nucleon separation energies and two-nucleon gaps. The correlation energy provides an explanation of 'mutually enhanced magicity'. (vi) The correlation energy tends to decrease the shell effect on binding energies around magic numbers, but the magnitude of the suppression is not large enough to explain the relative overbinding at N=82 and N=126 neutron-shell closures in mean-field models. (vii) Charge radii are also found to be sensitive to the quadrupole correlations. Static quadrupole deformations lead to a significant improvement of the overall systematics of charge radii. The dynamical correlations improve the local systematics of radii, in particular around shell closures. Although the dynamical correlations might reduce the charge radii for specific nuclei, they lead to an overall increase of radii when included, in particular in light nuclei.

  7. Lighthill quadrupole radiation in supersonic propeller acoustics

    NASA Astrophysics Data System (ADS)

    Peake, N.; Crighton, D. G.

    1991-02-01

    Sound generation by the Lighthill quadrupole is an important mechanism in the noise of supersonic and transonic propellers. Full numerical calculation of the quadrupole radiation, however, requires knowledge of the flow at all points exterior to the blades (involving transonic aerodynamics) and the evaluation of special functions. This paper describes how these difficulties may be largely avoided, using an asymptotic approximation that the number of blades, B, is large. It is proved that to leading order the problem of the radiation in a given direction reduces to one of determining the two-dimensional flow field at just one radial station, legitimately achieved by linearized supersonic analysis. Simple formulas are derived for the far-field acoustic pressure generated by unswept blades, from which absolute level predictions can be made accurately and quickly. These formulas predict a significantly greater intensity, over broad angular ranges, than is predicted by the linear theory for thickness noise sources.

  8. LARP Long Nb3Sn Quadrupole Design

    SciTech Connect

    Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidze, G.; Dietderich, D.; Feher, S.; Felice, H.; Ferracin, P.; /Fermilab /Brookhaven /LBL, Berkeley /Texas A-M

    2007-08-01

    A major milestone for the LHC Accelerator Research Program (LARP) is the test, by the end of 2009, of two 4m-long quadrupole magnets (LQ) wound with Nb3Sn conductor. The goal of these magnets is to be a proof of principle that Nb3Sn is a viable technology for a possible LHC luminosity upgrade. The design of the LQ is based on the design of the LARP Technological Quadrupoles, presently under development at FNAL and LBNL, with 90-mm aperture and gradient higher than 200 T/m. The design of the first LQ model will be completed by the end of 2007 with the selection of a mechanical design. In this paper we present the coil design addressing some fabrication technology issues, the quench protection study, and three designs of the support structure.

  9. Hydrogen isotope analysis by quadrupole mass spectrometry

    Microsoft Academic Search

    R. E. Ellefson; W. E. Moddeman; H. F. Dylla

    1981-01-01

    The analysis of isotopes of hydrogen (H,D,T) and helium (³He,⁴He) and selected impurities using a quadrupole mass spectrometer (QMS) has been investigated as a method of measuring the purity of tritium gas for injection into the Tokamak Fusion Test Reactor (TFTR). A QMS was used at low resolution, m\\/Dm<150, for quantifying impurities from m\\/q = 2 to 44, and at

  10. Electrostatic quadrupole DC accelerators for BNCT applications

    SciTech Connect

    Kwan, J.W.; Anderson, O.A.; Reginato, L.L.; Vella, M.C.; Yu, S.S.

    1994-04-01

    A dc electrostatic quadrupole (ESQ) accelerator is capable of producing a 2.5 MeV, 100 mA proton beam for the purpose of generating neutrons for Boron Neutron Capture Therapy. The ESQ accelerator is better than the conventional aperture column in high beam current application due to the presence of stronger transverse field for beam focusing and for suppressing secondary electrons. The major challenge in this type of accelerator is in developing the proper power supply system.

  11. Radio frequency quadrupole resonator for linear accelerator

    DOEpatents

    Moretti, Alfred (Downers Grove, IL)

    1985-01-01

    An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.

  12. Muon cooling in a quadrupole magnet channel

    SciTech Connect

    Neuffer, David; /Fermilab; Poklonskiy, A.; /Michigan State U.

    2007-10-01

    As discussed before,[1] a cooling channel using quadrupole magnets in a FODO transport channel can be used for initial cooling of muons. In the present note we discuss this possibility of a FODO focusing channel for cooling, and we present ICOOL simulations of muon cooling within a FODO channel. We explore a 1.5m cell-length cooling channel that could be used for the initial transverse cooling stage of a muon collider or neutrino factory.

  13. 15 T And Beyond - Dipoles and Quadrupoles

    SciTech Connect

    Sabbi, GianLuca

    2008-05-19

    Starting with the invention of the cyclotron by Lawrence, accelerator-based experiments have been the primary source of new discoveries in particle physics. In order to progress toward higher energy and luminosity, higher field magnets are required. R&D programs are underway to take advantage of new developments in superconducting materials, achieve better efficiency and simplify magnet fabrication while preserving accelerator-class field quality. A review of recent progress on high field dipole and quadrupole magnets is presented.

  14. Far-field potential production by quadrupole generators in cylindrical volume conductors.

    PubMed

    Dumitru, D; King, J C

    1993-01-01

    Far-field potentials have been observed clinically and recognized as such for approximately 30 years. Unfortunately a complete understanding of far-field potential generation is not yet at hand. An attractive model is the representation of an action potential by a quadrupole consisting of a leading and trailing dipole with respect to the direction of propagation. This investigation physically models an action potential by using a quadrupole constant current source and substantiates the concept that an action potential as modeled by two dipoles back-to-back is capable of producing far-field potentials in cylindrical volume conductors. The 4 postulated mechanisms of generating far-field potentials are validated, i.e., an action potential encountering (1) different size volume conductors, (2) the termination of excitable tissue, (3) a change in conducting medium conductivity, and (4) a bend in the nerve. A fifth postulated but previously not demonstrated method of far-field production, neural branching, is shown by the quadrupole model to also be capable of yielding far-field potentials. The termination of a volume conductor is also shown to be capable of generating a voltage difference across the quadrupole. Any of the above 6 conditions create an alteration in the symmetry of the leading and trailing dipole moments resulting in a transient potential difference across the quadrupole as recorded with a far-field recording montage. The potential difference produced by the asymmetric electric field between the leading and trailing dipoles recorded distantly in areas of low potential gradient is the so-called far-field potential. This investigation substantiates the utility of the leading/trailing dipole model of far-field production and offers a simple model of passive voltage distributions secondary to dipolar moment imbalances to better understand the generation of far-field potentials in cylindrical volume conductors. PMID:7691566

  15. Well-proportioned universes suppress CMB quadrupole

    E-print Network

    Jeffrey Weeks; Jean-Pierre Luminet; Alain Riazuelo; Roland Lehoucq

    2004-07-05

    A widespread myth asserts that all small universe models suppress the CMB quadrupole. In actual fact, some models suppress the quadrupole while others elevate it, according to whether their low-order modes are weak or strong relative to their high-order modes. Elementary geometrical reasoning shows that a model's largest dimension determines the rough value ell_min at which the CMB power spectrum ell(ell + 1)C_ell/(2pi) effectively begins; for cosmologically relevant models, ell_min < 4. More surprisingly, elementary geometrical reasoning shows that further reduction of a model's smaller dimensions -- with its largest dimension held fixed -- serves to elevate modes in the neighborhood of ell_min relative to the high-ell portion of the spectrum, rather than suppressing them as one might naively expect. Thus among the models whose largest dimension is comparable to or less than the horizon diameter, the low-order C_ell tend to be relatively weak in well-proportioned spaces (spaces whose dimensions are approximately equal in all directions) but relatively strong in oddly-proportioned spaces (spaces that are significantly longer in some directions and shorter in others). We illustrate this principle in detail for the special cases of rectangular 3-tori and spherical spaces. We conclude that well-proportioned spaces make the best candidates for a topological explanation of the low CMB quadrupole observed by COBE and WMAP.

  16. Photoassociation of a cold-atom-molecule pair: Long-range quadrupole-quadrupole interactions

    SciTech Connect

    Lepers, M.; Dulieu, O. [Laboratoire Aime Cotton, CNRS, UPR3321, Batiment 505, Universite Paris-Sud, F-91405 Orsay Cedex (France); Kokoouline, V. [Laboratoire Aime Cotton, CNRS, UPR3321, Batiment 505, Universite Paris-Sud, F-91405 Orsay Cedex (France); Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States)

    2010-10-15

    The general formalism of the multipolar expansion of electrostatic interactions is applied to the calculation of the potential energy between an excited atom (without fine structure) and a ground-state diatomic molecule at large mutual separations. Both partners exhibit a permanent quadrupole moment so that their mutual long-range interaction is dominated by a quadrupole-quadrupole term, which is attractive enough to bind trimers. Numerical results are given for an excited Cs(6{sup 2}P) atom and a ground-state Cs{sub 2} molecule. The prospects for achieving photoassociation of a cold-atom-dimer pair are thus discussed and found promising. The formalism can be generalized to the long-range interaction between molecules to investigate the formation of cold tetramers.

  17. Design of superconducting quadrupole magnets for CEBAF's Hall A spectrometer

    Microsoft Academic Search

    R. Kreutz; E. Brutsch; K. Dreher; H. Gruneberg; H. Lutkehaus; W. Nick; H. Peschel; B. Rzezonka; F. Sommer; P. Schafer

    1993-01-01

    The detailed design for the construction of the Q2\\/Q3 quadrupole magnets for CEBAF's Resolution Spectrometers is presented. The quadrupoles have a warm bore diameter of 600 mm and a cryostat length of 3 m. The quadrupole coil will be wound from a cable conductor carrying a current of 1850 A, the field gradient is 3.5 T\\/m. A set of eight

  18. A Ligand-Based Approach to Understanding Selectivity of Nuclear Hormone Receptors PXR, CAR, FXR, LXR?, and LXR?

    Microsoft Academic Search

    Sean Ekins; Leonid Mirny; Erin G. Schuetz

    2002-01-01

    In recent years discussion of nuclear hormone receptors, transporters, and drug-metabolizing enzymes has begun to take place as our knowledge of the overlapping ligand specificity of each of these proteins has deepened. This ligand specificity is potentially valuable information for influencing future drug design, as it is important to avoid certain enzymes or transporters in order to circumvent potential drug–drug

  19. Thermogravimetric-quadrupole mass-spectrometric analysis of geochemical samples.

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.; Johnson, S. M.

    1972-01-01

    Thermogravimetric-quadrupole mass-spectrometric-analysis techniques can be used to study a wide variety of problems involving decomposition processes and identification of released volatile components. A recording vacuum thermoanalyzer has been coupled with a quadrupole mass spectrometer. The rapid scan capabilities of the quadrupole mass spectrometer are used to identify the gaseous components released. The capability of the thermogravimetric-quadrupole mass spectrometer to provide analytical data for identification of the released volatile components, for determination of their sequence of release and for correlation of thermal-decomposition studies is illustrated by an analysis of the Orgueil carbonaceous chondrite.

  20. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, Philippe (3134 Natalie Cir., Augusta, GA 30909-2748)

    1993-01-01

    A quadrupole mass spectrometer (QMS) system having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

  1. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, P.

    1993-04-20

    A quadrupole mass spectrometer (QMS) system is described having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

  2. Magnetic mirror structure for testing shell-type quadrupole coils

    SciTech Connect

    Andreev, N.; Barzi, E.; Bossert, R.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; Tartaglia, N.; Turrioni, D.; /Fermilab

    2009-10-01

    This paper presents magnetic and mechanical designs and analyses of the quadrupole mirror structure to test single shell-type quadrupole coils. Several quadrupole coils made of different Nb{sub 3}Sn strands, cable insulation and pole materials were tested using this structure at 4.5 and 1.9 K. The coils were instrumented with voltage taps, spot heaters, temperature sensors and strain gauges to study their mechanical and thermal properties and quench performance. The results of the quadrupole mirror model assembly and test are reported and discussed.

  3. Analytical Solutions of Singular Isothermal Quadrupole Lens

    NASA Astrophysics Data System (ADS)

    Chu, Zhe; Lin, W. P.; Yang, Xiaofeng

    2013-06-01

    Using an analytical method, we study the singular isothermal quadrupole (SIQ) lens system, which is the simplest lens model that can produce four images. In this case, the radial mass distribution is in accord with the profile of the singular isothermal sphere lens, and the tangential distribution is given by adding a quadrupole on the monopole component. The basic properties of the SIQ lens have been studied in this Letter, including the deflection potential, deflection angle, magnification, critical curve, caustic, pseudo-caustic, and transition locus. Analytical solutions of the image positions and magnifications for the source on axes are derived. We find that naked cusps will appear when the relative intensity k of quadrupole to monopole is larger than 0.6. According to the magnification invariant theory of the SIQ lens, the sum of the signed magnifications of the four images should be equal to unity, as found by Dalal. However, if a source lies in the naked cusp, the summed magnification of the left three images is smaller than the invariant 1. With this simple lens system, we study the situations where a point source infinitely approaches a cusp or a fold. The sum of the magnifications of the cusp image triplet is usually not equal to 0, and it is usually positive for major cusps while negative for minor cusps. Similarly, the sum of magnifications of the fold image pair is usually not equal to 0 either. Nevertheless, the cusp and fold relations are still equal to 0 in that the sum values are divided by infinite absolute magnifications by definition.

  4. Multi-Pass Quadrupole Mass Analyzer

    NASA Technical Reports Server (NTRS)

    Prestage, John D.

    2013-01-01

    Analysis of the composition of planetary atmospheres is one of the most important and fundamental measurements in planetary robotic exploration. Quadrupole mass analyzers (QMAs) are the primary tool used to execute these investigations, but reductions in size of these instruments has sacrificed mass resolving power so that the best present-day QMA devices are still large, expensive, and do not deliver performance of laboratory instruments. An ultra-high-resolution QMA was developed to resolve N2 +/CO+ by trapping ions in a linear trap quadrupole filter. Because N2 and CO are resolved, gas chromatography columns used to separate species before analysis are eliminated, greatly simplifying gas analysis instrumentation. For highest performance, the ion trap mode is used. High-resolution (or narrow-band) mass selection is carried out in the central region, but near the DC electrodes at each end, RF/DC field settings are adjusted to allow broadband ion passage. This is to prevent ion loss during ion reflection at each end. Ions are created inside the trap so that low-energy particles are selected by low-voltage settings on the end electrodes. This is beneficial to good mass resolution since low-energy particles traverse many cycles of the RF filtering fields. Through Monte Carlo simulations, it is shown that ions are reflected at each end many tens of times, each time being sent back through the central section of the quadrupole where ultrahigh mass filtering is carried out. An analyzer was produced with electrical length orders of magnitude longer than its physical length. Since the selector fields are sized as in conventional devices, the loss of sensitivity inherent in miniaturizing quadrupole instruments is avoided. The no-loss, multi-pass QMA architecture will improve mass resolution of planetary QMA instruments while reducing demands on the RF electronics for high-voltage/high-frequency production since ion transit time is no longer limited to a single pass. The QMA-based instrument will thus give way to substantial reductions of the mass of flight instruments.

  5. Hybrid rare earth quadrupole drift tube magnets

    SciTech Connect

    Halbach, K.; Feinberg, B.; Green, M.I.; MacGill, R.; Milburn, J.; Tanabe, J.

    1985-10-01

    A prototype quadrupole permanent magnet with adjustable field strength has been constructed and tested. The magnet consists of iron pole pieces to provide the required field shape along with rare earth permanent magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field by rotating the outer rings consisting of permanent magnets and iron. Magnetic tests show small field errors coming from well understood assembly details. Mechanical tests show the design needs further consideration to ensure reliability. It is planned to use this type of magnet in the SuperHILAC prestripper drift tubes.

  6. Hybrid rare earth quadrupole drift tube magnets

    SciTech Connect

    Halbach, K.; Feinberg, B.; Green, M.I.; MacGill, R.; Milburn, J.; Tanabe, J.

    1985-05-01

    A prototype quadrupole permanent magnet with adjustable field strength has been constructed and tested. The magnet consists of iron pole pieces to provide the required field shape along with rare earth permanent magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field by rotating the outer rings consisting of permanent magnets and iron. Magnetic tests show small field errors coming from well understood assembly details. Mechanical tests show the design needs further consideration to ensure reliability. It is planned to use this type of magnet in the SuperHILAC prestripper drift tubes. 3 refs., 5 figs.

  7. Quadrupole Transfer Function for Emittance Measurement

    E-print Network

    Cameron, Peter; Jansson, Andreas; Tan, Cheng-Yang

    2008-01-01

    Historically the use of the quadrupole moment measurement has been impeded by the requirement for large dynamic range, as well as measurement sensitivity to beam position. We investigate the use of the transfer function technique [1-3] in combination with the sensitivity and 160dB revolution line rejection of the direct diode detection analog front end [4] to open the possibility of an emittance diagnostic that may be implemented without operational complication, quasi- parasitic to the operation of existing tune measurement systems. Such a diagnostic would be particularly useful as an emittance monitor during acceleration ramp development in machines like RHIC and the LHC.

  8. On the proper kinetic quadrupole CMB removal and the quadrupole anomalies

    NASA Astrophysics Data System (ADS)

    Notari, Alessio; Quartin, Miguel

    2015-06-01

    It has been pointed out recently that the quadrupole-octupole alignment in the CMB data is significantly affected by the so-called kinetic Doppler quadrupole (DQ), which is the temperature quadrupole induced by our proper motion. Assuming our velocity is the dominant contribution to the CMB dipole we have v/c=?=(1.231 ± 0.003) × 10?3, which leads to a non-negligible DQ of Script O(?2). Here we stress that one should properly take into account that CMB data are usually not presented in true thermodynamic temperature, which induces a frequency dependent boost correction. The DQ must therefore be multiplied by a frequency-averaged factor, which we explicitly compute for several Planck CMB maps finding that it varies between 1.67 and 2.47. This is often neglected in the literature and turns out to cause a small but non-negligible difference in the significance levels of some quadrupole-related statistics. For instance the alignment significance in the SMICA 2013 map goes from 2.3? to 3.3? with the frequency dependent DQ, instead of 2.9? ignoring the frequency dependence in the DQ. Moreover as a result of a proper DQ removal, the agreement across different map-making techniques is improved.

  9. Comparison of liquid chromatography using triple quadrupole and quadrupole ion trap mass analyzers to determine pesticide residues in oranges

    Microsoft Academic Search

    Carla Soler; Jordi Mañes; Yolanda Picó

    2005-01-01

    Liquid chromatography-triple quadrupole\\/mass spectrometry (LC-TQ\\/MS) and liquid chromatography-quadrupole ion trap\\/mass spectrometry (LC-QIT\\/MS) for determining bupirimate, hexaflumuron, tebufenpyrad, buprofezin, pyriproxyfen, and fluvalinate in fruits have been compared. The differences in the mass spectra obtained by triple and ion trap quadrupoles are discussed, showing how both of them provide interesting features. The evaluation of the two instruments was carried out by ethyl

  10. Supersonic Quadrupole Noise Theory for High-Speed Helicopter Rotors

    NASA Astrophysics Data System (ADS)

    Farassat, F.; Brentner, K. S.

    1998-12-01

    High-speed helicopter rotor impulsive noise prediction is an important problem of aeroacoustics. The deterministic quadrupoles have been shown to contribute significantly to high-speed impulsive (HSI) noise of rotors, particularly when the phenomenon of delocalization occurs. At high rotor-tip speeds, some of the quadrupole sources lie outside the sonic circle and move at supersonic speed. Brentner has given a formulation suitable for efficient prediction of quadrupole noise inside the sonic circle. In this paper, a simple formulation is presented based on the acoustic analogy that is valid for both subsonic and supersonic quadrupole noise prediction. Like the formulation of Brenter, the model is exact for an observer in the far field and in the rotor plane, and is approximate elsewhere. The full analytic derivation of this formulation is given in this paper. The method of implementation on a computer for supersonic quadrupoles using marching cubes for constructing the influence surface (?-surface) of an observer space-time variable (x,t) is presented. Then, several examples of noise prediction are given for both subsonic and supersonic quadrupoles. It is shown that in the case of transonic flow over rotor blades, the inclusion of the supersonic quadrupoles. It is shown that in the case of transonic flow over rotor blades, the inclusion of the supersonic quadrupoles improves the prediction of the acoustic pressure signature. The equivalence is shown of the new formulation to that of Brentner for subsonic quadrupoles. It is shown that the regions of high quadrupole source strength are primarily produced by the shock surface and the flow over the leading edge of the rotor. The primary role of the supersonic quadrupoles is to increase the width of a strong acoustic signal.

  11. LHC interaction region quadrupole cryostat design

    NASA Astrophysics Data System (ADS)

    Nicol, T. H.; Darve, Ch.; Huang, Y.; Page, T. M.

    2002-05-01

    The cryostat of a Large Hadron Collider (LHC) Interaction Region (IR) quadrupole magnet consists of all components of the inner triplet except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, to house all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations, and must be able to be manufactured at low cost. The major components of the cryostat are the vacuum vessel, thermal shield, multi-layer insulation system, cryogenic piping, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course of their expected operating lifetime. This paper describes the current LHC IR inner triplet quadrupole magnet cryostats being designed and manufactured at Fermilab as part of the US-LHC collaboration, and includes discussions on the structural and thermal considerations involved in the development of each of the major systems.

  12. SSC Quadrupole Magnet Performance at LBL

    SciTech Connect

    Lietzke, A.F.; Barale, P.; Benjegerdes, r.; Caspi, S.; Cortella, J.; Dell'Orco, D.; Gilbert, W.; Green, M.I.; Mirk, K.; Peters, C.; Scalan, R.; Taylor, C.E.; Wandesforde, A.

    1992-10-01

    Lawrence Berkeley Laboratory (LBL) contracted to design, construct, and test four short (1m) models and six full-size (5m) models of the Superconducting Super Collider (SSC) main-ring 5 meter focusing quadrupole magnet (211 Tesla/meter). The training performance of these magnets is summarized. Magnets were tested in a horizontal boiling helium (1 Atm) cryostat. The magnetic, strain-gage and training responses to two thermal cycles were measured. The quadrupole gradient, and relative multipole purity were determined from Fourier analysis of the rotating coil signals. Magnetic and strain-gage measurements were taken on-the-fly. The voltage-tap data was analyzed to determine quench-origin and propagation characteristics. Quench-training proceeded at 4.3K until a plateau was achieved or sub-cooling (2.5K) was used to accelerate the training process. The early short (1m) magnets were also trained at 1.8K (10kA) to help identify potential weak areas. The MIITs were calculated to compare various magnet protection methods. Except for modest training above the anticipated SSC operating point, the magnets performed very well and proved to be self-protecting. Some design flaws were identified and corrected. The last two 1 m models and all the 5m models have been reinstalled in cryostats at the SSC Laboratory, retested and used to achieve various milestones in their program.

  13. Is it possible to enhance the nuclear Schiff moment by nuclear collective modes?

    SciTech Connect

    Auerbach, N. [Tel Aviv University, School of Physics and Astronomy (Israel)], E-mail: auerbach@post.tau.ac.il; Dmitriev, V. F. [Budker Institute of Nuclear Physics (Russian Federation)], E-mail: v.f.dmitriev@inp.nsk.su; Flambaum, V. V. [University of New South Wales, School of Physics (Australia)], E-mail: flambaum@phys.unsw.edu.au; Lisetskiy, A. [GSI, Theory Department (Germany)], E-mail: olisetsk@theory.gsi.de; Sen'kov, R. A. [Budker Institute of Nuclear Physics (Russian Federation)], E-mail: senkov@nscl.msu.edu; Zelevinsky, V. G. [Michigan State University, National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy (United States)], E-mail: zelevins@nscl.msu.edu

    2007-09-15

    The nuclear Schiff moment is predicted to be enhanced in nuclei with static quadrupole and octupole deformation. The analogous suggestion of the enhanced contribution to the Schiff moment from the soft collective quadrupole and octupole vibrations in spherical nuclei is tested in the framework of the quasiparticle random phase approximation with separable quadrupole and octupole forces applied to the odd {sup 217-221}Ra and {sup 217-221}Rn isotopes. In this framework, we confirm the existence of the enhancement effect due to the soft modes, but only in the limit when the frequencies of quadrupole and octupole vibrations are close to zero.

  14. Ion-quadrupole effects in ion-molecule collisions.

    NASA Technical Reports Server (NTRS)

    Dugan, J. V., Jr.; Palmer, R. W.

    1972-01-01

    Ion-quadrupole effects are investigated via numerical calculations of capture cross sections and computer-plotter studies of ion trajectories in the quadrupole field. Capture cross sections are roughly equal to Langevin values for low rotational temperatures; a large fraction of multiple reflection captures are calculated corresponding to formation of ion-molecule complexes.

  15. Adjustable Permanent Quadrupoles for the Next Linear Collider

    Microsoft Academic Search

    C. M. Spencer; Cherrill M

    2001-01-01

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to 20% and effective lengths from 324 mm to 972 mm.

  16. Adjustable permanent quadrupoles for the Next Linear Collider

    Microsoft Academic Search

    James T. Volk; J. DiMarco; G. W. Foster; W. Fowler; V. S. Kashikhin; A. Makarov; V. Tsvetkov; C. E. Rago; A. Ringwall; C. M. Spencer; Z. Wolf

    2001-01-01

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to -20% and effective lengths from 324 mm to 972 mm,.

  17. Electrostatic quadrupole focused particle accelerating assembly with laminar flow beam

    DOEpatents

    Maschke, A.W.

    1984-04-16

    A charged particle accelerating assembly provided with a predetermined ratio of parametric structural characteristics and with related operating voltages applied to each of its linearly spaced focusing and accelerating quadrupoles, thereby to maintain a particle beam traversing the electrostatic fields of the quadrupoles in the assembly in an essentially laminar flow through the assembly.

  18. Nuclear

    NSDL National Science Digital Library

    Iowa Public Television. Explore More Project

    2004-01-01

    What part does nuclear energy play in satisfying energy demands? This informational piece, part of a series about the future of energy, introduces students to the uranium atom as an energy source. Here students read about the history of nuclear energy, how energy is derived from uranium, and benefits of nuclear energy. Information is also provided about limitations, particularly disposal problems and radioactivity, and geographical considerations of nuclear power in the United States. Thought-provoking questions afford students chances to reflect on what they've read about the uses of nuclear power. Articles and information on new nuclear plant design and nuclear accidents are available from a sidebar. Five energy-related PBS NewsHour links are provided. A web link to the U.S. Nuclear Regulatory Commission is included. Copyright 2005 Eisenhower National Clearinghouse

  19. Commissioning a Vibrating Wire System for Quadrupole Fiducialization

    SciTech Connect

    Levashov, Michael Y

    2010-12-03

    Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of the quadrupoles. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing such a system. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet center (step 1), finding the wire with position detectors (step 2), and finding the quadrupole tooling ball positions relative to the position detector tooling balls (step 3). A previous study investigated the error associated with each step by using a permanent quadrupole magnet on an optical mover system. The study reported an error of 11{micro}m for step 1 and a repeatability of 4{micro}m for step 2. However, the set up used a FARO arm to measure tooling balls and didn't allow to accurately check step 2 for errors; an uncertainty of 100{micro}m was reported. Therefore, even though the repeatability was good, there was no way to check that the error in step 2 was small. Following the recommendations of that study, we used a CMM (Coordinate Measuring Machine) instead of the FARO arm for measuring the tooling balls. In addition, a roller cam positioner system replaced the optical movers for moving the quadrupole. With the exception of the quadrupole itself, the system was identical to what will be used in fiducializing the undulator quadrupoles. In this study, we investigate the new vibrating wire set up, including the error associated with each step of fiducialization. A vibrating wire system was constructed to fiducialize the quadrupoles between undulator segments in the LCLS. This note is a continuation of previous work to study the ability of the system to fulfill the fiducialization requirements.

  20. Double-photoionization of helium including quadrupole radiation effects

    SciTech Connect

    Colgan, James [Los Alamos National Laboratory; Ludlow, J A [AUBURN UNIV; Lee, Teck - Ghee [AUBURN UNIV; Pindzola, M S [AUBURN UNIV; Robicheaux, F [AUBURN UNIV

    2009-01-01

    Non-perturbative time-dependent close-coupling calculations are carried out for the double photoionization of helium including both dipole and quadrupole radiation effects. At a photon energy of 800 eV, accessible at CUlTent synchrotron light sources, the quadrupole interaction contributes around 6% to the total integral double photoionization cross section. The pure quadrupole single energy differential cross section shows a local maxima at equal energy sharing, as opposed to the minimum found in the pure dipole single energy differential cross section. The sum of the pure dipole and pure quadrupole single energy differentials is insensitive to non-dipole effects at 800 eV. However, the triple differential cross section at equal energy sharing of the two ejected electrons shows strong non-dipole effects due to the quadrupole interaction that may be experimentally observable.

  1. Coupling Current and AC Loss in LHC Superconducting Quadrupoles

    E-print Network

    Di Castro, M; Richter, D; Sanfilippo, S; Wolf, R

    2008-01-01

    One of the issues for the operation of the LHC accelerator at CERN are the field errors generated by coupling currents in the superconducting cables of the main dipoles and quadrupoles, especially during the initial phase of the energy ramp from injection conditions. Coupling current effects have already been measured in the superconducting dipoles, and results are reported elsewhere. This paper reports similar measurements that we have recently performed on different types of LHC superconducting quadrupoles (arc quadrupole, dispersion suppressor and matching section quadrupoles) to quantify the above effects and compare them to the values specified from the beam tolerances. Loss and field errors due to ramping are mainly determined by the contact resistance Rc between the strands of the magnets cables. In this paper the Rc is calculated for several quadrupoles measured using both the measured energy loss and the magnetic field errors during ramping of magnets.

  2. Nondestructive testing of adhesive bonds by nuclear quadrupole resonance method

    NASA Technical Reports Server (NTRS)

    Hewitt, R. R.

    1971-01-01

    Inert, strain sensitive tracer, cuprous oxide, added to polymeric adhesive ensures sufficiently large signal to noise ratio in NQR system output. Method is successful, provided that RF-transparent structural materials are used between modified adhesive and probe of NQR spectrometer.

  3. Table of Nuclear Magnetic Dipole and Electric Quadrupole Moments

    E-print Network

    compilation] and to the journal. Listings of abbreviations used to identify methods and journals are given Arrangement of the Table 3 List of annotations ** List of Experimental Method abbreviations used ** Literature Reference abbreviation list ** General Introduction This Table comprises a listing of measured magnetic

  4. Quantitative Analysis of Hydration Using Nitrogen-14 Nuclear Quadrupole Resonance.

    PubMed

    Gregorovi?, Alan

    2015-07-01

    Hydration is a quite common process in pharmaceutical solids. Sometimes it is desirable, as it stabilizes the crystal structure; in other cases it is unwanted, as it changes the physical and chemical properties of drugs. We here use (14)N NQR spectroscopy to quantitatively analyze hydration of a model compound, 5-aminotetrazole. (14)N NQR has some great advantages compared to other routinely used techniques to study hydration, like a very simple spectrum, single point calibration, and no need for special sample preparation, but the method's great disadvantage is a rather small sensitivity. Nevertheless, here we demonstrate that (14)N NQR, although being significantly less sensitive than XRD, NIR, and also (35)Cl NQR, is still capable of providing excellent quantitative accuracies. We can achieve errors <1% of the total amount, provided good temperature stabilization is implemented, which then allows long experimental times. We also present results obtained with a SLSE pulse sequence, which is a less robust approach but allows the use of much shorter measuring times (?200×) and could be used for quantitative real time monitoring of hydration or dehydration. PMID:26008906

  5. OT2_jmartinp_4: The Galactic center as the laboratory to understand nuclear activity in galaxies (GC_JMP)

    NASA Astrophysics Data System (ADS)

    Martín-Pintado, J.

    2011-09-01

    We propose to use the The Galactic center (GC) a local extragalactic laboratory to understand the chemistry and the heating mechanisms in nearby galactic nuclei. The central 30 pc region around the black hole, Sgr A*, contains all the different type of activity found in extragalactic nuclei, namely, massive stellar clusters creating large photodissociation regions (PDR), shocks, molecular clouds irradiated by strong X-rays (XDRs), and the site of Cosmic Rays (CRs) acceleration as shown by HESS. We plan to map this region with SPIRE in the high spectral resolution mode and with HIFI in selected molecular ions H_3O^+, OH^+, and H_2O^+ claimed to trace XDRs and/or CRs. This unique data set will provide the possibility to understand the origin of the large column densities of this hydrides found in galactic nuclei with different type of activity and the role of the PDR-XDR-CR chemistries in their formation. The SPIRE data cubes will have a huge legacy value providing the full FIR inventory of the atomic and molecular gas across the central 50 pc of the Galaxy. We stress that only the combination of the high spectral resolution of HIFI and the spatial distribution provided the proposed mapping will have the possibility to distinguish which of the different components of the molecular gas along the line of sight correspond to the ones associated with XDRs PDRs and eventually CRs acceleration sites.

  6. A graphical approach to radio frequency quadrupole design

    NASA Astrophysics Data System (ADS)

    Turemen, G.; Unel, G.; Yasatekin, B.

    2015-07-01

    The design of a radio frequency quadrupole, an important section of all ion accelerators, and the calculation of its beam dynamics properties can be achieved using the existing computational tools. These programs, originally designed in 1980s, show effects of aging in their user interfaces and in their output. The authors believe there is room for improvement in both design techniques using a graphical approach and in the amount of analytical calculations before going into CPU burning finite element analysis techniques. Additionally an emphasis on the graphical method of controlling the evolution of the relevant parameters using the drag-to-change paradigm is bound to be beneficial to the designer. A computer code, named DEMIRCI, has been written in C++ to demonstrate these ideas. This tool has been used in the design of Turkish Atomic Energy Authority (TAEK)'s 1.5 MeV proton beamline at Saraykoy Nuclear Research and Training Center (SANAEM). DEMIRCI starts with a simple analytical model, calculates the RFQ behavior and produces 3D design files that can be fed to a milling machine. The paper discusses the experience gained during design process of SANAEM Project Prometheus (SPP) RFQ and underlines some of DEMIRCI's capabilities.

  7. A Graphical Approach to Radio Frequency Quadrupole Design

    E-print Network

    Turemen, G; Yasatekin, B

    2014-01-01

    The design of a radio frequency quadrupole, an important section of all ion accelerators, and the calculation of its beam dynamics properties can be achieved using the existing computational tools. These programs, originally designed in 1980s, show effects of aging in their user interfaces and in their output. The authors believe there is room for improvement in both design techniques using a graphical approach and in the amount of analytical calculations before going into CPU burning finite element analysis techniques. Additionally an emphasis on the graphical method of controlling the evolution of the relevant parameters using the drag-to-change paradigm is bound to be beneficial to the designer. A computer code, named DEMIRCI, has been written in C++ to demonstrate these ideas. This tool has been used in the design of Turkish Atomic Energy Authority (TAEK)'s 1.5 MeV proton beamline at Saraykoy Nuclear Research and Training Center (SANAEM). DEMIRCI starts with a simple analytical model, calculates the RFQ b...

  8. Quadrupole resonance scanner for narcotics detection

    NASA Astrophysics Data System (ADS)

    Shaw, Julian D.; Moeller, C. R.; Magnuson, Erik E.; Sheldon, Alan G.

    1994-10-01

    Interest in non-invasive, non-hazardous, bulk detection technologies for narcotics interdiction has risen over the last few years. As part of our continuing research and development programs in detection of narcotics and explosives using sensitive magnetic measuring devices, we present the first commercially available prototype Quadrupole Resonance (QR) scanner for narcotics detection. The portable narcotics detection system was designed in modular form such that a single QR base system could be easily used with a variety of custom detection heads. The QR system presented in this paper is suitable for scanning items up to 61 X 35 X 13 cm in size, and was designed to scan mail packages and briefcase-sized items for the presence of narcotics. System tests have shown that detection sensitivity is comparable that obtained in laboratory systems.

  9. An improved integrally formed radio frequency quadrupole

    DOEpatents

    Abbott, S.R.

    1987-10-05

    An improved radio frequency quadrupole is provided having an elongate housing with an elongate central axis and top, bottom and two side walls symmetrically disposed about the axis, and vanes formed integrally with the walls, the vanes each having a cross-section at right angles to the central axis which tapers inwardly toward the axis to form electrode tips spaced from each other by predetermined distances. Each of the four walls, and the vanes integral therewith, is a separate structural element having a central lengthwise plane passing through the tip of the vane, the walls having flat mounting surfaces at right angles to and parallel to the control plane, respectively, which are butted together to position the walls and vane tips relative to each other. 4 figs.

  10. Equations of motion for binary systems with relativistic quadrupole-quadrupole moments interaction

    Microsoft Academic Search

    Xuejun Wu; Yuejuan He; Chongming Xu

    1998-01-01

    By making use of the scheme developed by Damour, Soffel and Xu, in terms of Maple-computer algebra system, the first post-Newtonian\\u000a equations of motion for binary systems with monopole, spin and quadrupole interaction are for the first time derived in an\\u000a explicit and complete form. The equations of motion are expressed in the local coordinate system as well as in

  11. Quadrupole Coupling Parameters and Structural Aspects of Crystalline and Amorphous Solids by NMR and Nqr.

    NASA Astrophysics Data System (ADS)

    Mao, Degen

    Nuclear quadrupole interaction is very sensitive to the local electron distribution and chemical bondings. NMR and NQR techniques have been combined to obtain the quadrupole coupling constant ({Qcc}) and asymmetry parameter (eta) and extract structural information for several borate, gallate, and metavanadate compounds and glasses. ^{71}Ga and ^{69}Ga NMR has been used to study crystalline beta-Ga _2O_3 and several gallate glasses. Quadrupole parameters were acquired for GaO_6 and GaO_4 units in beta-Ga_2 O_3 by the computer simulation of the NMR powder patterns. A sensitive CW NQR spectrometer was built to detect NQR resonances below 2 MHz. The spectrometer includes a modified Robinson oscillator-detector, a new bi-symmetric square wave Zeeman modulator and a computerized data acquisition system. ^{51}V (I = 7/2) NQR resonances below 850 kHz have been detected for several metavanadates at both room temperature and liquid nitrogen temperature. Quadrupole parameters thus obtained are an order of magnitude more accurate than values obtained by previous NMR studies. For a spin 3/2 nucleus, the pure NQR frequency {Q_{cc}over 2}sqrt{1+{eta^2over 3}}is insufficient to determine either Q_{cc} or eta. However, two methods, Zeeman perturbed NQR powder pattern and ^{10}B NQR, can be employed to obtain both Q_{cc } and eta. An example is given for ^{11}B in CaO-B_2O_3. With a double coil tank circuit design, pure ^ {11}B NQR was used to determine the fraction of borons in BO_3 and BO _4 configurations in hydrated zinc borates. ^{11}B NMR and NQR were also used to study lead borate glasses. Small changes in Q_{cc} (less than 2%) and eta (less than 0.1) suggest that BO_3 units with non-bridging oxygens are not present in the lead borate glasses.

  12. Quadrupole beam-based alignment in the RHIC interaction regions

    SciTech Connect

    Ziegler, J.; Satogata, T.

    2011-03-28

    Continued beam-based alignment (BBA) efforts have provided significant benefit to both heavy ion and polarized proton operations at RHIC. Recent studies demonstrated previously unknown systematic beam position monitor (BPM) offset errors and produced accurate measurements of individual BPM offsets in the experiment interaction regions. Here we describe the algorithm used to collect and analyze data during the 2010 and early 2011 RHIC runs and the results of these measurements. BBA data has been collected over the past two runs for all three of the active experimental IRs at RHIC, updating results from the 2005 run which were taken with incorrectly installed offsets. The technique was successfully applied to expose a systematic misuse of the BPM survey offsets in the control system. This is likely to benefit polarized proton operations as polarization transmission through acceleration ramps depends on RMS orbit control in the arcs, but a quantitative understanding of its impact is still under active investigation. Data taking is ongoing as are refinements to the BBA technique aimed at reducing systematic errors and properly accounting for dispersive effects. Further development may focus on non-triplet BPMs such as those located near snakes, or arc quadrupoles that do not have individually shunted power supplies (a prerequisite for the current method) and as such, will require a modified procedure.

  13. High-Efficiency Resonant Cavity Quadrupole Moment Monitor

    SciTech Connect

    Barov, N.; Nantista, C.D.; Miller, R.H.; Kim, J.S.; /FARTECH, San Diego /SLAC

    2007-04-13

    Measurement of the beam quadrupole moment at several locations can be used to reconstruct the beam envelope and emittance parameters. The measurements can be performed in a non-intercepting way using a set of quadrupole-mode cavities. We present a cavity design with an optimized quadrupole moment shunt impedance. The cavity properties can be characterized using a wire test method to insure symmetry about the central axis, and alignment to nearby position sensing cavities. The design and characterization of the prototype structure is discussed.

  14. Self-consistent methods in nuclear structure physics

    SciTech Connect

    Dobaczewski, J. [Warsaw Univ. (Poland). Inst. of Theoretical Physics][Oak Ridge National Lab., TN (United States). Joint Inst. for Heavy Ion Research]|[Univ. of Tennessee, Knoxville, TN (United States). Dept. of Physics

    1997-11-01

    The authors present a very brief description of the Hartree Fock method in nuclear structure physics, discuss the numerical methods used to solve the self-consistent equations, and analyze the precision and convergence properties of solutions. As an application, they present results pertaining to quadrupole moments and single-particle quadrupole polarizations in superdeformed nuclei with A {approximately} 60.

  15. The Low-Energy Quadrupole Mode of Nuclei

    E-print Network

    Frauendorf, S

    2015-01-01

    The phenomenological classification of collective quadrupole excitations by means of the Bohr Hamiltonian is reviewed with focus on signatures for triaxility. The variants of the microscopic Bohr Hamiltonian derived by means of the Adiabatic Time Dependent Mean Field theory from the Pairing plus Quadrupole-Quadrupole interaction, the Shell Correction Method, the Skyrme Energy Density Functional, the Relativistic Mean Field Theory, and the Gogny interaction are discussed and applications to concrete nuclides reviewed. The Generator Coordinate Method for the five dimensional quadrupole deformation space and first applications to triaxial nuclei are presented. The phenomenological classification in the framework of the Interacting Boson Model is discussed with a critical view on the boson number counting rule. The recent success in calculating the model parameters by mapping the mean field deformation energy surface on the bosonic one is discussed and the applications listed. A critical assessment of the models ...

  16. Electro-Magnetic Quadrupole Magnets in the LCLS FEL Undulator

    SciTech Connect

    Emma, P.

    2005-01-31

    We discuss various aspects of electro-magnetic quadrupole (EMQ) magnets for the LCLS FEL undulator, including their utility in beam-based alignment (BBA), magnet design issues, and impact on tunnel environment, reliability, and cost.

  17. Alignment tolerances of IR quadrupoles in the LHC

    SciTech Connect

    Tanaji Sen

    1999-11-05

    Luminosity in the LHC will depend critically on the alignment of the triplet quadrupoles. These quadrupoles are closest to the interaction points (IPs), have large gradients and the {beta} functions have their largest values within these quadrupoles. Within a triplet, the cold masses of the Q1 and Q3 quadrupoles will be housed in separate cryostats while Q2a and Q2b will be placed in a single cryostat. The absolute alignments of Q1, Q3 and the Q2a/Q2b pair with respect to the desired axes will be determined during installation. The relative alignment of Q2a and Q2b however will be fixed once they are placed in their common cryostat at Fermilab. In this note, we examine the required relative alignment tolerances of Q2a and Q2b. An early study of some alignment tolerances was done by Weisz [1].

  18. Field quality and stability of permanent magnet quadrupoles

    SciTech Connect

    Herb, S.

    1985-10-01

    We plan to increase the peak luminosity of the Cornell Electron Storage Ring by providing tighter vertical focussing at the interaction points. The final focussing devices will be large permanent magnet quadrupoles operating inside the 10-15 kG solenoidal field of the experimental detector. We present the results of tests demonstrating that quadrupoles with the required field quality and resistance to demagnetization can be built from commercially available Rare Earth Cobalt magnets.

  19. Variable-field permanent-magnet quadrupole for the SSC

    Microsoft Academic Search

    David B. Barlow; Robert H. Kraus Jr; Ricardo P. Martinez; Ross E. Meyer

    1994-01-01

    A set of compact variable-field permanent-magnet quadrupoles have been designed, fabricated, and tested for use in the SSC linac matching section. The quadrupoles have 24 mm-diameter apertures and 40 mm-long poles. The hybrid (permanent-magnet and iron) design, uses a fixed core of magnet material (NdFeB) and iron (C-1006) surrounded by a rotating ring of the same magnet material and iron.

  20. Variable-field permanent magnet quadrupole for the SSC

    Microsoft Academic Search

    D. B. Barlow; R. H. Jr. Kraus; R. P. Martinez; R. E. Meyer

    1993-01-01

    A set of compact variable-field permanent-magnet quadrupoles have been designed, fabricated, and tested for use In the SSC linac matching section. The quadrupoles have 24 mm-diameter apertures and 40 mm-long poles. The hybrid (permanent-magnet and iron) design, uses a fixed core of magnet material (NdFeB) and iron (C-1006) surrounded by a rotating ring of the same magnet material and iron.

  1. Quadrupole resonance spectroscopic study of narcotic materials

    NASA Astrophysics Data System (ADS)

    Rayner, Timothy J.; West, Rebecca; Garroway, Allen N.; Lyndquist, R.; Yesinowski, James P.

    1997-02-01

    Bulk narcotic detection systems based upon Quadrupole Resonance Analysis (QRA) technology have a major advantage over imaging technologies, in that QRA is chemical-specific and consequently has a lower rate of false alarms. QRA is a magnetic resonance technology which occurs as a result of the inherent molecular properties of the atomic nuclei in crystalline and amorphous solids. The QRA response is characterized by 1) the precessional frequency of the nucleus, and 2) the nature of the electric field gradient experienced by the nucleus,due to its molecular environment. Another important detection parameter is linewidth, resonant quality. All of these parameters depend on sample purity and manufacturing process. Quantum Magnetics recently carried out a study on the QRA signatures of various narcotic materials with the support of the US Army, US Customs, and the Office of National Drug Control Policy. The aim of the study was to fully characterize the variation in QRA spectroscopic parameters of different samples of cocaine base and cocaine hydrochloride. The results from this study ar discussed here.

  2. Adjustable rare earth quadrupole drift tube magnets

    SciTech Connect

    Feinberg, B.; Tanabe, J.; Halbach, K.; Koehler, G.; Green, M.I.

    1987-03-01

    A prototype permanent-magnet drift tube quadrupole with adjustable field strength has been constructed and tested. The magnet uses iron pole pieces to provide the required field shape along with rare earth permanent-magnet material (samarium cobalt) to energize the magnet. A unique feature of the configuration is the adjustability of the field, accomplished by rotating the outer rings consisting of permanent magnets and iron. In contrast with a previous prototype magnet, this new design uses ball bearings in place of slide bearings to eliminate potential failures. The rotation is now achieved with a bevel gear mechanism. The prototype design also incorporates a new drift tube shell vacuum seal to allow easy disassembly. Tests were made of the magnetic properties and the mechanical performance of this magnet. Field errors are extremely small, and the magnet passed an accelerated ten year lifetime test. It is planned to use this type of magnet to replace 24 of the SuperHILAC prestripper drift tubes.

  3. Thermal Analysis of the ILC Superconductin Quadrupole

    SciTech Connect

    Ross, Ian; /Rose-Hulman Inst., Terre Haute /SLAC

    2006-09-13

    Critical to a particle accelerator's functioning, superconducting magnets serve to focus and aim the particle beam. The Stanford Linear Accelerator Center (SLAC) has received a prototype superconducting quadrupole designed and built by the Centro de Investigaciones Energ{acute e}ticas, Medioambientales y Tecnol{acute o}gicas (CIEMAT) to be evaluated for the International Linear Collider (ILC) project. To ensure proper functioning of the magnet, the device must be maintained at cryogenic temperatures by use of a cooling system containing liquid nitrogen and liquid helium. The cool down period of a low temperature cryostat is critical to the success of an experiment, especially a prototype setup such as this one. The magnet and the dewar each contain unique heat leaks and material properties. These differences can lead to tremendous thermal stresses. The system was analyzed mathematically, leading to ideal liquid helium and liquid nitrogen flow rates during the magnet's cool-down to 4.2 K, along with a reasonable estimate of how long this cool-down will take. With a flow rate of ten gaseous liters of liquid nitrogen per minute, the nitrogen shield will take approximately five hours to cool down to 77 K. With a gaseous helium flow rate of sixty liters per minute, the magnet will take at least nineteen hours to cool down to a temperature of 4.2 K.

  4. Autonomously Calibrating a Quadrupole Mass Spectrometer

    NASA Technical Reports Server (NTRS)

    Lee, Seungwon; Bornstein, Benjamin J.

    2009-01-01

    A computer program autonomously manages the calibration of a quadrupole ion mass spectrometer intended for use in monitoring concentrations and changes in concentrations of organic chemicals in the cabin air of the International Space Station. The instrument parameters calibrated include the voltage on a channel electron multiplier, a discriminator threshold, and an ionizer current. Calibration is achieved by analyzing the mass spectrum obtained while sweeping the parameter ranges in a heuristic procedure, developed by mass spectrometer experts, that involves detection of changes in signal trends that humans can easily recognize but cannot necessarily be straightforwardly codified in an algorithm. The procedure includes calculation of signal-to-noise ratios, signal-increase rates, and background-noise-increase rates; finding signal peaks; and identifying peak patterns. The software provides for several recovery-from-error scenarios and error-handling schemes. The software detects trace amounts of contaminant gases in the mass spectrometer and notifies associated command- and-data-handling software to schedule a cleaning. Furthermore, the software autonomously analyzes the mass spectrum to determine whether the parameters of a radio-frequency ramp waveform are set properly so that the peaks of the mass spectrum are at expected locations.

  5. Errors in radio-frequency quadrupole structures

    SciTech Connect

    Lysenko, W.P.

    1983-01-01

    Performance degradation caused by certain radio-frequency quadrupole (RFQ) machine errors was studied using an efficient 3-D particle-tracing simulation code for a high-brightness example. Matched beams, for which no emittance growth occurs, exist for periodic structures and were used as input beams for particle tracing in the presence of errors. We considered both slowly varying and fast (random) errors that destroy periodicity. Random dipole errors cause emittance growth because of the mismatches they introduce and also result in a motion of the beam centroid that causes a reduction in acceptance. Because of the way RFQs are manufactured, the random error amplitudes can be kept below harmful levels. More important are the slow errors, which are harmful because they reduce acceptance even though they maintain a match (up to the point of particle loss). Slow dipole errors steer the beam toward the wall, and voltage deficiencies cause instabilities in the longitudinal direction resulting in particles not being accelerated to full energy.

  6. Table of Nuclear Moments

    Microsoft Academic Search

    P. Raghavan

    1989-01-01

    This table is a compilation of experimental data on static nuclear magnetic dipole ane electric quadrupole moments for ground state and excited states of nuclides from ¹H to ²⁵⁴Es. Listed along with the moments are the associated excitation energy, half-life, spin, and parity of the nuclear state, and the experimental method employed. The literature has been surveyed through early 1988.

  7. Commissioning of helium injector for coupled radio frequency quadrupole and separated function radio frequency quadrupole accelerator

    SciTech Connect

    Peng, Shixiang, E-mail: sxpeng@pku.edu.cn; Chen, Jia; Ren, Haitao; Zhao, Jie; Xu, Yuan; Zhang, Tao; Xia, Wenlong; Gao, Shuli; Wang, Zhi; Luo, Yuting; Guo, Zhiyu [SKLNPT and IHIP, School of Physics, Peking University, Beijing 100871 (China)] [SKLNPT and IHIP, School of Physics, Peking University, Beijing 100871 (China); Zhang, Ailing; Chen, Jia'er [SKLNPT and IHIP, School of Physics, Peking University, Beijing 100871 (China) [SKLNPT and IHIP, School of Physics, Peking University, Beijing 100871 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

    2014-02-15

    A project to study a new type of acceleration structure has been launched at Peking University, in which a traditional radio frequency quadrupole (RFQ) and a separated function radio frequency quadrupole are coupled in one cavity to accelerate the He+ beam. A helium injector for this project is developed. The injector consists of a 2.45 GHz permanent magnet electron cyclotron resonance ion source and a 1.16 m long low energy beam transport (LEBT). The commissioning of this injector was carried out and an onsite test was held in June 2013. A 14 mA He+ beam with the energy of 30 keV has been delivered to the end of the LEBT, where a diaphragm with the diameter of 7 mm is located. The position of the diaphragm corresponds to the entrance of the RFQ electrodes. The beam emittance and fraction were measured after the 7 mm diaphragm. Its rms emittance is about 0.14 ??mm?mrad and the fraction of He+ is about 99%.

  8. The Photon Polarization Parameter of 2H(n, ?)3H reaction with Inclusion of the Electric Quadrupole Contribution

    NASA Astrophysics Data System (ADS)

    Sadeghi, H.; Mosavi-Khansari, M.

    2014-09-01

    We use effective field theory (EFT) for the calculation of neutron—deuteron radiative capture at very low energies. We present here the use of EFT to calculate a low-energy photo-nuclear observable in three-body systems, the photon polarization parameter and fore—aft asymmetry at thermal neutron energies up to next-to-next to leading order (N2LO), with inclusion of the electric quadrupole contribution. The photon polarization parameter in total is found to be Rc = ?0.421 ± 0.003 and is in good agreement with the other modern theoretical calculations based on modern nucleon—nucleon potentials. In comparison with our previous work, a satisfactory agreement with the available experimental data is found by inclusion of the electric quadrupole contribution.

  9. Higher order parametric excitation modes for spaceborne quadrupole mass spectrometers

    NASA Astrophysics Data System (ADS)

    Gershman, D. J.; Block, B. P.; Rubin, M.; Benna, M.; Mahaffy, P. R.; Zurbuchen, T. H.

    2011-12-01

    This paper describes a technique to significantly improve upon the mass peak shape and mass resolution of spaceborne quadrupole mass spectrometers (QMSs) through higher order auxiliary excitation of the quadrupole field. Using a novel multiresonant tank circuit, additional frequency components can be used to drive modulating voltages on the quadrupole rods in a practical manner, suitable for both improved commercial applications and spaceflight instruments. Auxiliary excitation at frequencies near twice that of the fundamental quadrupole RF frequency provides the advantages of previously studied parametric excitation techniques, but with the added benefit of increased sensed excitation amplitude dynamic range and the ability to operate voltage scan lines through the center of upper stability islands. Using a field programmable gate array, the amplitudes and frequencies of all QMS signals are digitally generated and managed, providing a robust and stable voltage control system. These techniques are experimentally verified through an interface with a commercial Pfeiffer QMG422 quadrupole rod system. When operating through the center of a stability island formed from higher order auxiliary excitation, approximately 50% and 400% improvements in 1% mass resolution and peak stability were measured, respectively, when compared with traditional QMS operation. Although tested with a circular rod system, the presented techniques have the potential to improve the performance of both circular and hyperbolic rod geometry QMS sensors.

  10. Higher Order Parametric Excitation Modes for Spaceborne Quadrupole Mass Spectrometers

    NASA Technical Reports Server (NTRS)

    Gershman, D. J.; Block, B. P.; Rubin, M.; Benna, M.; Mahaffy, P. R.; Zurbuchen, T. H.

    2011-01-01

    This paper describes a technique to significantly improve upon the mass peak shape and mass resolution of spaceborne quadrupole mass spectrometers (QMSs) through higher order auxiliary excitation of the quadrupole field. Using a novel multiresonant tank circuit, additional frequency components can be used to drive modulating voltages on the quadrupole rods in a practical manner, suitable for both improved commercial applications and spaceflight instruments. Auxiliary excitation at frequencies near twice that of the fundamental quadrupole RF frequency provides the advantages of previously studied parametric excitation techniques, but with the added benefit of increased sensed excitation amplitude dynamic range and the ability to operate voltage scan lines through the center of upper stability islands. Using a field programmable gate array, the amplitudes and frequencies of all QMS signals are digitally generated and managed, providing a robust and stable voltage control system. These techniques are experimentally verified through an interface with a commercial Pfeiffer QMG422 quadrupole rod system.When operating through the center of a stability island formed from higher order auxiliary excitation, approximately 50% and 400% improvements in 1% mass resolution and peak stability were measured, respectively, when compared with traditional QMS operation. Although tested with a circular rod system, the presented techniques have the potential to improve the performance of both circular and hyperbolic rod geometry QMS sensors.

  11. MEQALAC: (multiple electrostatic quadrupole linac): a new approach to low beta rf acceleration

    SciTech Connect

    Mobley, R.M.; Brodowski, J.J.; Gammel, G.M.; Keane, J.T.; Maschka, A.W.; Sanders, R.T.

    1980-01-01

    MEQALAC is an acronym for a multiple-beam electrostatic-quadrupole array linear accelerator. The principle of operation is very simple. It makes use of the fact that electrostatic quadrupoles focus more effectively at low velocities than conventional magnetic quadrupoles. Moreover, the pole-tip field of an electrostatic quadrupole is limited by field emission of electrons, and is not a function of the size of the quadrupole. Conventional magnetic quadrupoles, on the other hand, require increasingly high current densities if one attempts to scale to smaller size.

  12. Advanced Hydrotest Facility (AHF) large bore quadrupole focusing magnet system

    SciTech Connect

    Jason, A. J. (Andrew J.); Walstrom, P. L. (Peter L.); Waynert, J. A. (Joseph A.); Schultz, J. (Joel); Camille, R. J.; Antaya, T. (Thomas); Myatt, R. L.; Minervini, J.; Radovinsky, A.; Smith, B. A. (Brian A.)

    2002-01-01

    The Advanced Hydrotest Facility (AHF) at Los Alamos will provide proton radiography of large-scale, dynamic events. The large bore (Case II) quadrupole focusing magnets are a subsystem in this facility, consisting of four complete imaging lines with a total of eight imaging plates and 52 quadrupole magnets. Each large bore quadrupole has an inner winding diameter of 660 mm and provides a gradient of 10.4 T/m with a 300 mm field of view. Each magnet is a two-layer saddle, contained by a three cm steel shell. The conductor is a Rutherford cable, soldered into a C-shaped copper channel. The magnets are cooled by the forced-flow of two-phase helium through coolant pipes. Since the winding must absorb bursts of 0.35 J/kg irradiation, both NbTi and Nb{sub 3}Sn designs are being considered.

  13. Quadrupole moments of odd-odd near-magic nuclei

    NASA Astrophysics Data System (ADS)

    Voitenkov, D.; Achakovskiy, O.; Kamerdzhiev, S.; Tolokonnikov, S.

    2012-12-01

    Ground state quadrupole moments of odd-odd near-double-magic nuclei are calculated in the approximation of non-interacting odd neutron and odd proton. Under such a simple approximation the problem is reduced to the calculations of quadrupole moments of corresponding odd-even nuclei. These calculations are performed within the self-consistent Theory of Finite Fermi Systems based on the Energy Density Functional by Fayans et al. with the known DF3-a parameters. A reasonable agreement with the available experimental data is obtained for odd-odd nuclei and odd near-magic nuclei investigated. The self-consistent approach under consideration allowed us to predict the unknown quadrupole moments of odd-even and odd-odd nuclei near the double-magic 56,78Ni, 100,132Sn nuclides.

  14. Cryogen free superconducting splittable quadrupole magnet for linear accelerators

    SciTech Connect

    Kashikhin, V.S.; Andreev, N.; Kerby, J.; Orlov, Y.; Solyak, N.; Tartaglia, M.; Velev, G.; /Fermilab

    2011-09-01

    A new superconducting quadrupole magnet for linear accelerators was fabricated at Fermilab. The magnet is designed to work inside a cryomodule in the space between SCRF cavities. SCRF cavities must be installed inside a very clean room adding issues to the magnet design, and fabrication. The designed magnet has a splittable along the vertical plane configuration and could be installed outside of the clean room around the beam pipe previously connected to neighboring cavities. For more convenient assembly and replacement a 'superferric' magnet configuration with four racetrack type coils was chosen. The magnet does not have a helium vessel and is conductively cooled from the cryomodule LHe supply pipe and a helium gas return pipe. The quadrupole generates 36 T integrated magnetic field gradient, has 600 mm effective length, and the peak gradient is 54 T/m. In this paper the quadrupole magnetic, mechanical, and thermal designs are presented, along with the magnet fabrication overview and first test results.

  15. Study of a micro chamber quadrupole mass spectrometer

    SciTech Connect

    Wang Jinchan; Zhang Xiaobing; Mao Fuming; Xiao Mei; Cui Yunkang; Engelsen, Daniel den; Lei Wei [Jiangsu Information Display Engineering Research Center, School of Electronic Science and Engineering, Southeast University, Nanjing 210096 (China)

    2008-03-15

    The design of a micro chamber quadrupole mass spectrometer (MCQMS) having a small total volume of only 20 cm{sup 3}, including Faraday cup ion detector and ion source, is described. This MCQMS can resist a vacuum baking temperature of 400-500 deg. C. The quadrupole elements with a hyperbolic surface are made of a ceramic material and coated with a thin metal layer. The quadrupole mass filter has a field radius of 3 mm and a length of 100 mm. Prototypes of this new MCQMS can detect a minimum partial pressure of 10{sup -8} Pa, have a peak width of {delta}M=1 at 10% peak height from mass number 1 to 60, and show an excellent long-term stability. The new MCQMS is intended to be used in residual gas analyses of electron devices during a mutual pumping and baking process.

  16. Variable-field permanent-magnet quadrupole for the SSC

    SciTech Connect

    Barlow, D.B.; Kraus, R.H. Jr.; Martinez, R.P.; Meyer, R.E. [Los Alamos National Lab., NM (United States)] [Los Alamos National Lab., NM (United States)

    1994-07-01

    A set of compact variable-field permanent-magnet quadrupoles have been designed, fabricated, and tested for use in the SSC linac matching section. The quadrupoles have 24 mm-diameter apertures and 40 mm-long poles. The hybrid (permanent-magnet and iron) design, uses a fixed core of magnet material (NdFeB) and iron (C-1006) surrounded by a rotating ring of the same magnet material and iron. The quadrupole gradient-length product can be smoothly varied from a minimum of 0.7 T up to a maximum of 4.3 T by a 90{degree} rotation of the outer ring of iron and magnet material.

  17. Variable-field permanent-magnet quadrupole for the SSC

    NASA Astrophysics Data System (ADS)

    Barlow, David B.; Kraus, Robert H., Jr.; Martinez, Ricardo P.; Meyer, Ross E.

    1994-07-01

    A set of compact variable-field permanent-magnet quadrupoles have been designed, fabricated, and tested for use in the SSC linac matching section. The quadrupoles have 24 mm-diameter apertures and 40 mm-long poles. The hybrid (permanent-magnet and iron) design, uses a fixed core of magnet material (NdFeB) and iron (C-1006) surrounded by a rotating ring of the same magnet material and iron. The quadrupole gradient-length product can be smoothly varied from a minimum of 0.7 T up to a maximum, of 4.3 T by a 90 deg rotation of the outer ring of iron and magnet material.

  18. Stability of an Aqueous Quadrupole Micro-Trap

    PubMed Central

    Park, Jae Hyun; Krsti?, Predrag S.

    2011-01-01

    Recently demonstrated functionality of an aqueous quadrupole micro- or nano-trap opens a new avenue for applications of the Paul traps, like is confinement of a charged biomolecule which requires water environment for its chemical stability. Besides strong viscosity forces, motion of a charged particle in the aqueous trap is subject to dielectrophoretic and electrophoretic forces. In this study, we describe the general conditions for stability of a charged particle in an aqueous quadrupole trap. We find that for the typical micro-trap parameters, effects of both dielectrophoresis and electrophoresis significantly influence the trap stability. In particular, the aqueous quadrupole trap could play of a role of a synthetic virtual nanopore for the 3rd generation of DNA sequencing technology. PMID:22466254

  19. A microelectromechanical systems-enabled, miniature triple quadrupole mass spectrometer.

    PubMed

    Wright, Steven; Malcolm, Andrew; Wright, Christopher; O'Prey, Shane; Crichton, Edward; Dash, Neil; Moseley, Richard W; Zaczek, Wojciech; Edwards, Peter; Fussell, Richard J; Syms, Richard R A

    2015-03-17

    Miniaturized mass spectrometers are becoming increasingly capable, enabling the development of many novel field and laboratory applications. However, to date, triple quadrupole tandem mass spectrometers, the workhorses of quantitative analysis, have not been significantly reduced in size. Here, the basis of a field-deployable triple quadrupole is described. The key development is a highly miniaturized ion optical assembly in which a sequence of six microengineered components is employed to generate ions at atmospheric pressure, provide a vacuum interface, effect ion guiding, and perform fragmentation and mass analysis. Despite its small dimensions, the collision cell efficiently fragments precursor ions and yields product ion spectra that are very similar to those recorded using conventional instruments. The miniature triple quadrupole has been used to detect thiabendazole, a common pesticide, in apples at a level of 10 ng/g. PMID:25708099

  20. Variable-field permanent magnet quadrupole for the SSC

    SciTech Connect

    Barlow, D.B.; Kraus, R.H. Jr.; Martinez, R.P.; Meyer, R.E.

    1993-10-01

    A set of compact variable-field permanent-magnet quadrupoles have been designed, fabricated, and tested for use In the SSC linac matching section. The quadrupoles have 24 mm-diameter apertures and 40 mm-long poles. The hybrid (permanent-magnet and iron) design, uses a fixed core of magnet material (NdFeB) and iron (C-1006) surrounded by a rotating ring of the same magnet material and iron. The quadrupole gradient-length product can be smoothly varied from a minimum of 0.7 T up to a maximum, of 4.3 T by a 90{degrees} rotation of the outer ring of iron and magnet material.

  1. Quadrupole moment of the nucleon in chiral constituent quark model

    E-print Network

    Harleen Dahiya; Neetika Sharma

    2010-09-10

    The electromagnetic form factors are the most fundamental quantities to describe the internal structure of the nucleon and the shape of a spatially extended particle is determined by its {\\it intrinsic} quadrupole moment which is first order moment of the charge density operator. With some experimental indications of a deformed nucleon, we have calculated the {\\it intrinsic} quadrupole moment of the octet and decuplet baryons in the framework of chiral constituent quark model \\chiCQM which is quite successful in explaining some of the important baryon properties in the nonperturbative regime.

  2. An Estimate of the Maximum Gradients in Superconducting Quadrupoles

    E-print Network

    Todesco, Ezio

    2007-01-01

    In this paper we show that the electromagnetic design of several superconducting quadrupoles, built for particle accelerators, can be rather well approximated by a 36 degree sector coil with a wedge, canceling the first two field harmonics. We therefore carry out a complete analysis of this lay-out, obtaining an approximated equation for the critical gradient as a function of the coil area, magnet aperture, and of the superconducting properties of the cable. Using this model, we estimate through numerical methods the maximum critical gradient that can be obtained in quadrupole of a given aperture for Nb-Ti, Nb-Ti-Ta and Nb3Sn.

  3. A 40 mm bore quadrupole magnet for the SSC

    SciTech Connect

    Taylor, C.E.; Barale, P.; Caspi, S.; Dell'Orco, D.; Fritz, D.; Gilbert, W.S.; Lietzke, A.; Peters, C.; Wandesforde, A.

    1990-09-01

    A 40 mm bore quadrupole magnet design, called QC'', has been made for the SSC with the following parameters: 208 T/m gradient at 6500A, 2-layer cos 2 {theta}'' winding arrangement with 30 strand cable and one spacer wedge per coil. Structural support is provided by self-supporting interlocking collars; two types of symmetrical laminations are pre-assembled into collar packs for ease of assembly. This paper will describe the design of a prototype quadrupole magnet for the SSC and preliminary tests results on 1 m models. 7 refs., 6 figs., 2 tabs.

  4. High and ulta-high gradient quadrupole magnets

    SciTech Connect

    Brunk, W.O.; Walz, D.R.

    1985-05-01

    Small bore conventional dc quadrupoles with apertures from 1 to 2.578cm were designed and prototypes built and measured. New fabrication techniques including the use of wire electric discharge milling (EDM) to economically generate the pole tip contours and aperture tolerances are described. Magnetic measurement data from a prototype of a 1cm aperture quadrupole with possible use in future e/sup +//e/sup -/ super colliders are presented. At a current of 400A, the lens achieved a gradient of 2.475 T/cm, and had an efficiency of 76.6%.

  5. Nuclear Energy Level Argument for a Spheroidal Nuclear Model

    Microsoft Academic Search

    James Rainwater

    1950-01-01

    Recently there has been notable success, particularly by Maria Mayer, in explaining many nuclear phenomena including spins, magnetic moments, isomeric states, etc. on the basis of a single particle model for the separate nucleons in a spherical nucleus. The spherical model, however, seems incapable of explaining the observed large quadrupole moments of nuclei. In this paper it is shown that

  6. Quadrupole terms in defect energies in transition metal oxides

    Microsoft Academic Search

    A. M. Stoneham; M. J. L. Sangster; J. H. Harding

    1990-01-01

    In a previous paper it was shown that, for defects in transition metal oxides, there was evidence for an additional term in the potential energy beyond the usual monopole and dipole terms of the shell model. This appeared to be a quadrupole term in which the open 3d shells of the host ions, as well as any impurities, responded to

  7. Hydrogen atom in a magnetic field: The quadrupole moment

    NASA Astrophysics Data System (ADS)

    Potekhin, Alexander Y.; Turbiner, Alexander V.

    2001-06-01

    The quadrupole moment of a hydrogen atom in a magnetic field B for field strengths from 0 to 4.414×1013 G is calculated by two different methods. The first method is variational, and based on a single trial function. The second method deals with a solution of the Schrödinger equation in the form of a linear combination of Landau orbitals.

  8. LHC interaction region quadrupole cryostat design and fabrication

    Microsoft Academic Search

    Thomas H. Nicol; Christine Darve; Yuenian Huang; Thomas M. Page

    2002-01-01

    The cryostat of a Large Hadron Collider (LHC) Interaction Region (IR) quadrupole magnet consists of all components of the inner triplet except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, to house all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It

  9. Quadrupole Model Magnet R&D Alexander Zlobin, Fermilab

    E-print Network

    Large Hadron Collider Program

    Ti superconductor. Quadrupole parameters: ­ 70 mm coil aperture ­ 205 T/m nominal gradient with 20% margin ­ 1.9 K Generation LHC IRs Baseline LHC inner triplets consist of single-bore, high-gradient quads based on Nb analysis shows that the aperture limit for Nb3Sn quads is 110 mm for the present operating field gradient

  10. Kalman filtering for enhanced landmine detection using quadrupole resonance

    Microsoft Academic Search

    Yingyi Tan; Stacy L. Tantum; Leslie M. Collins

    2005-01-01

    Quadrupole resonance (QR) is a novel technology recently applied to landmine detection. The detection process is specific to the chemistry of the explosive, and therefore is less susceptible to the types of false alarms experienced by metal detectors and ground-penetrating radars. Although QR is vulnerable to radio-frequency interference (RFI) when the sensor is deployed in the field, adaptive RFI mitigation

  11. Chaos and catastrophies in quadrupole oscillations of nuclei

    SciTech Connect

    Bolotin, Y.L.; Gonchar, V.Y.; Inopin, E.V.

    1987-02-01

    The dynamics of the quadrupole oscillations of nuclei is studied. The possibility of a transition from the regular regime to a chaotic regime is investigated, and the critical energy of such a transition is determined for different values of the parameters of the potential.

  12. The exact calculation of quadrupole sources for some incompressible flows

    Microsoft Academic Search

    Kenneth S. Brentner

    1988-01-01

    This paper is concerned with the application of the acoustic analogy of Lighthill to the acoustic and aerodynamic problems associated with moving bodies. The Ffowcs Williams-Hawkings equation, which is an interpretation of the acoustic analogy for sound generation by moving bodies, manipulates the source terms into surface and volume sources. Quite often in practice the volume sources, or quadrupoles, are

  13. The Low-Energy Quadrupole Mode of Nuclei

    E-print Network

    S. Frauendorf

    2015-06-20

    The phenomenological classification of collective quadrupole excitations by means of the Bohr Hamiltonian is reviewed with focus on signatures for triaxility. The variants of the microscopic Bohr Hamiltonian derived by means of the Adiabatic Time Dependent Mean Field theory from the Pairing plus Quadrupole-Quadrupole interaction, the Shell Correction Method, the Skyrme Energy Density Functional, the Relativistic Mean Field Theory, and the Gogny interaction are discussed and applications to concrete nuclides reviewed. The Generator Coordinate Method for the five dimensional quadrupole deformation space and first applications to triaxial nuclei are presented. The phenomenological classification in the framework of the Interacting Boson Model is discussed with a critical view on the boson number counting rule. The recent success in calculating the model parameters by mapping the mean field deformation energy surface on the bosonic one is discussed and the applications listed. A critical assessment of the models is given with focus on the limitations due to the adiabatic approximation. The Tidal Wave approach and the Triaxial Projected Shell Model are presented as practical approaches to calculate spectral properties outside the adiabatic region.

  14. Binary systems with monopole, spin, and quadrupole moments

    Microsoft Academic Search

    Chongming Xu; Xuejun Wu; Gerhard Schäfer

    1997-01-01

    The first post-Newtonian equations of motion for binary systems with monopole, spin, and quadrupole interactions are for the first time derived in an explicit and complete form making use of the scheme developed by Damour, Soffel, and Xu, especially their second paper. The equations of motion are expressed in the local coordinate system of body A (B) as well as

  15. Understanding language

    E-print Network

    Pettit, Dean R. (Dean Reid), 1967-

    2003-01-01

    My dissertation concerns the nature of linguistic understanding. A standard view about linguistic understanding is that it is a propositional knowledge state. The following is an instance of this view: given a speaker S ...

  16. Large-Aperture Nb3Sn Quadrupoles for 2 nd generation LHC IRs1

    Microsoft Academic Search

    A. V. Zlobin; E. Barzi; D. Chichili; Yu. Huang; V. V. Kashikhin; M. Lamm; P. J. Limon; N. Mokhov; I. Novitski; T. Peterson; J. B. Strait; S. Yadav

    The 1 st generation of low-beta quadrupoles for the LHC interaction region (IR) was designed to achieve the nominal LHC luminosity of 10 34 cm -2 s -1 . Given that the lifetime of the 1 st generation IR quadrupoles is limited by ionizing radiation to 6-7 years, the 2 nd generation of IR quadrupoles has to be developed with

  17. Ground-state and pairing-vibrational bands with equal quadrupole collectivity in 124Xe

    NASA Astrophysics Data System (ADS)

    Radich, A. J.; Garrett, P. E.; Allmond, J. M.; Andreoiu, C.; Ball, G. C.; Bianco, L.; Bildstein, V.; Chagnon-Lessard, S.; Cross, D. S.; Demand, G. A.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Hackman, G.; Hadinia, B.; Jigmeddorj, B.; Laffoley, A. T.; Leach, K. G.; Michetti-Wilson, J.; Orce, J. N.; Rajabali, M. M.; Rand, E. T.; Starosta, K.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Wang, Z. M.; Wood, J. L.; Wong, J.; Williams, S. J.; Yates, S. W.

    2015-04-01

    The nuclear structure of 124Xe has been investigated via measurements of the ?+/EC decay of 124Cs with the 8 ? ? -ray spectrometer at the TRIUMF-ISAC facility. The data collected have enabled branching ratio measurements of weak, low-energy transitions from highly excited states, and the 2+?0+ in-band transitions have been observed. Combining these results with those from a previous Coulomb excitation study, B (E 2 ;23+?02+) =78 (13 ) W.u. and B (E 2 ;24+?03+) =53 (12 ) W.u. were determined. The 03+ state, in particular, is interpreted as the main fragment of the proton-pairing vibrational band identified in a previous 122Te (3He,n )124Xe measurement, and has quadrupole collectivity equal to, within uncertainty, that of the ground-state band.

  18. SP(6,R) Symmetry and the Giant Quadrupole Resonance in MAGNESIUM-24.

    NASA Astrophysics Data System (ADS)

    Reske, Edward John

    1984-06-01

    Microscopic nuclear calculations are approached by partitioning the many-nucleon Hilbert space as a direct sum of symplectic bands. Computational techniques and algorithms which utilize commutator methods, and which are more powerful than the more straight-forward purely shell-model approach, are developed for calculating the matrix elements of two-body operators within such an Sp(6,R) (R-HOOK) U(3) symmetry-adapted basis. These techniques may be generalized to n-body operators of any n. These computational tools are applied to the study of the Giant Quadrupole Resonance in ('24)Mg: the final calculation presented uses a microscopic Hamiltonian consisting of the kinetic energy plus the semi-realistic two-body Brink -Boeker B1 potential within a space consisting of three symplectic bands up to 6(H/2PI)(omega) total excitation.

  19. Nuclear reactions in hot stellar matter and nuclear surface deformation

    E-print Network

    V. Yu. Denisov

    2006-11-13

    Cross-sections for capture reactions of charged particles in hot stellar matter turn out be increased by the quadrupole surface oscillations, if the corresponding phonon energies are of the order of the star temperature. The increase is studied in a model that combines barrier distribution induced by surface oscillations and tunneling. The capture of charged particles by nuclei with well-deformed ground-state is enhanced in stellar matter. It is found that the influence of quadrupole surface deformation on the nuclear reactions in stars grows, when mass and proton numbers in colliding nuclei increase.

  20. Microwave spectrum, van der Waals bond length, and 131Xe quadrupole coupling constant of Xe-SO3

    NASA Astrophysics Data System (ADS)

    Dewberry, Christopher T.; Huff, Anna K.; Mackenzie, Rebecca B.; Leopold, Kenneth R.

    2014-10-01

    Nine isotopologues of Xe-SO3 have been observed by pulsed-nozzle Fourier transform microwave spectroscopy. The complex is a symmetric top with a Xe-S van der Waals distance of 3.577(2) Å. The increase in rare gas distance relative to that in Kr-SO3 is equal to the difference in van der Waals radii between Xe and Kr. The 131Xe nuclear quadrupole coupling constant indicates that the electric field gradient at the xenon nucleus is 78% larger than that at the Kr nucleus in Kr-SO3.

  1. Electron-scale nested quadrupole Hall field in Cluster observations of magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Jain, N.; Sharma, A. S.

    2015-06-01

    This paper presents the first evidence of a new and unique feature of spontaneous reconnection at multiple sites in electron current sheet, viz. a "nested quadrupole" structure of the Hall field at electron scales, in Cluster observations. The new nested quadrupole is a consequence of electron-scale processes in reconnection. Whistler response of the upstream plasma to the interaction of electron flows from neighboring reconnection sites produces a large-scale quadrupole Hall field enclosing the quadrupole fields of the multiple sites, thus forming a nested structure. Electron-magnetohydrodynamic simulations of an electron current sheet yields a mechanism of the formation of a nested quadrupole.

  2. Hyperfine and quadrupole interactions of trigonal 157 Gd 3+ centers in SrF 2 and BaF 2 . Analysis of distortions in the nearest atomic environment

    Microsoft Academic Search

    A. D. Gorlov; A. P. Potapov

    2000-01-01

    Trigonal 157Gd3+ impurity centers in SrF2 and BaF2 were experimentally studied by EPR and double electron-nuclear resonance (DENR) techniques. Parameters of the hyperfine and\\u000a quadrupole interactions between these centers were determined. Possible distortions of the nearest atomic environment of the\\u000a impurity centers are estimated within the framework of a superposition model using the EPR and DENR data for the centers

  3. Extension of the level mixing resonance (LMR) method to study the alignment and the quadrupole moment of light exotic projectile fragments

    Microsoft Academic Search

    G. Neyens; R. Nouwen; R. Coussement

    1994-01-01

    The level mixing resonance (LMR) method has proven to be a very powerful method to measure the quadrupole interaction frequency of long-lived low-spin nuclear states which decay through gamma-radiation [R. Coussement et al., Hyperfine Interactions 23 (1985) 273, G. Scheveneels et al., ibid., 52 (1989) 257, 179]. In this paper the concept of LMR has been extended for beta-decaying nuclei

  4. Test results of LHC interaction regions quadrupoles produced by Fermilab

    SciTech Connect

    Bossert, R.; Carson, J.; Chichili, D.R.; Feher, S.; Kerby, J.; Lamm, M.J.; Nobrega, A.; Nicol, T.; /Fermilab; Ogitsu, T.; /KEK, Tsukuba; Orris, D.; Page, T.; Peterson, T.; Rabehl, R.; Robotham, W.; /Fermilab; Scanlan, R.; /LBL, Berkeley; Schlabach, P.; Sylvester, C.; Strait, J.; Tartaglia, M.; Tompkins, J.C.; Velev, G.; /Fermilab

    2004-10-01

    The US-LHC Accelerator Project is responsible for the production of the Q2 optical elements of the final focus triplets in the LHC interaction regions. As part of this program Fermilab is in the process of manufacturing and testing cryostat assemblies (LQXB) containing two identical quadrupoles (MQXB) with a dipole corrector between them. The 5.5 m long Fermilab designed MQXB have a 70 mm aperture and operate in superfluid helium at 1.9 K with a peak field gradient of 215 T/m. This paper summarizes the test results of several production MQXB quadrupoles with emphasis on quench performance and alignment studies. Quench localization studies using quench antenna signals are also presented.

  5. SKEW QUADRUPOLES IN RHIC DIPOLE MAGNETS AT HIGH FIELDS.

    SciTech Connect

    JAIN, A.; GUPTA, P.; THOMPSON, P.; WANDERER, P.

    1995-06-11

    In the RHIC arc dipoles, the center of the cold mass lies above the center of the cryostat. At the maximum design field, the magnetic flux lines leak through the yoke to the asymmetrically located cryostat, which provides an additional return path. This introduces a systematic top-bottom asymmetry leading to a skew quadrupole term at high fields. A similar asymmetry is also created by any difference in weights of the upper and the lower yoke halves. Data from measurements of several RHIC dipoles are presented to study this effect. In the current production series of the RDIC dipoles, an attempt is made to compensate the effect of the cryostat by an asymmetry in the iron yoke. Seven dipoles with this type of yoke have been cold tested, and show a reduced saturation in the skew quadrupole term, as expected.

  6. Skew quadrupole in RHIC dipole magnets at high fields

    SciTech Connect

    Jain, A.; Gupta, R.; Thompson, P.; Wanderer, P. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States)

    1996-07-01

    In the RHIC are dipoles, the center of the cold mass lies above the center of the cryostat. At the maximum design field, the magnetic flux lines leak through the yoke to the asymmetrically located cryostat, which provides an additional return path. This introduces a systematic top-bottom asymmetry leading to a skew quadrupole term at high fields. A similar asymmetry is also created by any difference in weights of the upper and the lower yoke halves. Data from measurements of several RHIC dipoles are presented to study this effect. In the current production series of the RHIC dipoles, an attempt is made to compensate the effect of the cryostat by an asymmetry in the iron yoke. Seven dipoles with this type of yoke have been cold tested, and show a reduced saturation in the skew quadrupole term, as expected.

  7. Skew quadrupole in RHIC dipole magnets at high fields

    SciTech Connect

    Jain, A.; Gupta, P.; Thompson, P.; Wanderer, P.

    1995-07-01

    In the RHIC arc dipoles, the center of the cold mass lies above the center of the cryostat. At the maximum design field, the magnetic flux lines leak through the yoke to the asymmetrically located cryostat, which provides an additional return path. This introduces a systematic top-bottom asymmetry leading to a skew quadrupole term at high fields. A similar asymmetry is also created by any difference in weights of the upper and the lower yoke halves. Data from measurements of several RHIC dipoles are presented to study this effect. In the current production series of the RHIC dipoles, an attempt is made to compensate the effect of the cryostat by an asymmetry in the iron yoke. Seven dipoles with this type of yoke have been cold tested, and show a reduced saturation in the skew quadrupole term, as expected.

  8. Nb3Sn Quadrupoles Designs For The LHC Upgrades

    SciTech Connect

    Felice, Helene

    2008-05-19

    In preparation for the LHC luminosity upgrades, high field and large aperture Nb{sub 3}Sn quadrupoles are being studied. This development has to incorporate all the relevant features for an accelerator magnet like alignment and cooling channels. The LARP HQ model is a high field and large bore quadrupole that will meet these requirements. The 2-layer coils are surrounded by a structure based on key and bladder technology with supporting iron yoke and aluminum shell. This structure is aimed at pre-stress control, alignment and field quality. We present here the magnetic and mechanical design of HQ, along with recent progress on the development of the first 1-meter model.

  9. Superferric quadrupoles for FAIR Super FRS energy buncher

    NASA Astrophysics Data System (ADS)

    Pal, G.; Bhunia, U.; Akhter, J.; Nandi, C.; Datta, A.; Sarma, P. R.; Roy, S.; Bajirao, S.; Bhattacharyya, S.; Bhattacharyya, T. K.; Dey, M. K.; Mallik, C.; Bhandari, R. K.

    2012-12-01

    The quadrupole magnets for FAIR Super FRS energy buncher have large usable aperture, high magnetic pole-tip field and high gradient field quality. The iron-dominated magnets with superconducting coils have to be used in this application. The NbTi coil, laminated iron, and support structure of about 22 tons is immersed in liquid helium. The 4.5 K helium chamber is completely covered with a thermal shield cooled by helium at 50-80 K on its outer and inner surface. The helium chamber and thermal shield is enclosed in a vacuum shell. The paper presents design details of the long quadrupole. Coupled thermal, magnetic and structural analysis was carried out to design the magnet iron, magnet coil, helium vessel and support links and ensure the required gradient field quality is achieved. The paper also presents the design of support links and outer vacuum chamber.

  10. 120-mm superconducting quadrupole for interaction regions of hadron colliders

    E-print Network

    Zlobin, A V; Mokhov, N V; Novitski, I

    2012-01-01

    Magnetic and mechanical designs of a Nb3Sn quadrupole magnet with 120-mm aperture suitable for interaction regions of hadron colliders are presented. The magnet is based on a two-layer shell-type coil and a cold iron yoke. Special spacers made of a low-Z material are implemented in the coil mid-planes to reduce the level of radiation heat deposition and radiation dose in the coil. The quadrupole mechanical structure is based on aluminum collars supported by an iron yoke and a stainless steel skin. Magnet parameters including maximum field gradient and field harmonics, Nb3Sn coil pre-stress and protection at the operating temperatures of 4.5 and 1.9 K are reported. The level and distribution of radiation heat deposition in the coil and other magnet components are discussed.

  11. Performance of An Adjustable Strength Permanent Magnet Quadrupole

    SciTech Connect

    Gottschalk, S.C.; DeHart, T.E.; Kangas, K.W.; /STI Optronics, Bellevue; Spencer, C.M.; /SLAC; Volk, J.T.; /Fermilab

    2006-03-01

    An adjustable strength permanent magnet quadrupole suitable for use in Next Linear Collider has been built and tested. The pole length is 42cm, aperture diameter 13mm, peak pole tip strength 1.03Tesla and peak integrated gradient * length (GL) is 68.7 Tesla. This paper describes measurements of strength, magnetic CL and field quality made using an air bearing rotating coil system. The magnetic CL stability during -20% strength adjustment proposed for beam based alignment was < 0.2 microns. Strength hysteresis was negligible. Thermal expansion of quadrupole and measurement parts caused a repeatable and easily compensated change in the vertical magnetic CL. Calibration procedures as well as CL measurements made over a wider tuning range of 100% to 20% in strength useful for a wide range of applications will be described. The impact of eddy currents in the steel poles on the magnetic field during strength adjustments will be reported.

  12. New Mechanical Concept for Nb$_{3}$Sn Quadrupole

    E-print Network

    Karppinen, Mikko

    2014-01-01

    A new mechanical design concept for the Nb3Sn quadrupoles has been developed with a goal of an accelerator quality magnet that can be industrially produced in large series. This concept can easily be extended to any length and applied on both 1-in-1 and 2-in-1 configurations. It is based on the pole-loading concept and collared coils using dipole-type collars. First conceptual design study using finite element analysis has been carried out using the present base-line HL-LHC IR quadrupole QXF coil geometry for direct comparison with the bladder-and-key structure. The main features of the new design concept are described and the main results of the structural analysis discussed.

  13. 120-mm supercondcting quadrupole for interaction regions of hadron colliders

    SciTech Connect

    Zlobin, A.V.; Kashikhin, V.V.; Mokhov, N.V.; Novitski, I.; /Fermilab

    2010-05-01

    Magnetic and mechanical designs of a Nb{sub 3}Sn quadrupole magnet with 120-mm aperture suitable for interaction regions of hadron colliders are presented. The magnet is based on a two-layer shell-type coil and a cold iron yoke. Special spacers made of a low-Z material are implemented in the coil mid-planes to reduce the level of radiation heat deposition and radiation dose in the coil. The quadrupole mechanical structure is based on aluminum collars supported by an iron yoke and a stainless steel skin. Magnet parameters including maximum field gradient and field harmonics, Nb3Sn coil pre-stress and protection at the operating temperatures of 4.5 and 1.9 K are reported. The level and distribution of radiation heat deposition in the coil and other magnet components are discussed.

  14. Analysis on linac quadrupole misalignment in FACET commissioning 2012

    SciTech Connect

    Sun, Yipeng; /SLAC

    2012-07-05

    In this note, the analysis on linac quadrupole misalignment is presented for the FACET linac section LI05-09 plus LI11-19. The effectiveness of the beam-based alignment technique is preliminarily confirmed by the measurement. Beam-based alignment technique was adopted at SLAC linac since SLC time. Here the beam-based alignment algorithms are further developed and applied in the FACET commissioning during 2012 run.

  15. 120-mm supercondcting quadrupole for interaction regions of hadron colliders

    Microsoft Academic Search

    A. V. Zlobin; V. V. Kashikhin; N. V. Mokhov; I. Novitski

    2010-01-01

    Magnetic and mechanical designs of a NbSn quadrupole magnet with 120-mm aperture suitable for interaction regions of hadron colliders are presented. The magnet is based on a two-layer shell-type coil and a cold iron yoke. Special spacers made of a low-Z material are implemented in the coil mid-planes to reduce the level of radiation heat deposition and radiation dose in

  16. Design and Measurement of the NSLS II Quadrupole Prototypes

    SciTech Connect

    Rehak,M.; Jain, A. K.; Skaritka, J.; Spataro, C.

    2009-05-04

    The design and measurement of the NSLS-II ring quadrupoles prototypes are presented. These magnets are part of a larger prototype program described in [1]. Advances in software, hardware, and manufacturing have led to some new level of insight in the quest for the perfect magnet design. Three geometric features are used to minimize the first three allowed harmonics by way of optimization. Validations through measurement and confidence levels in calculations are established.

  17. Borehole dipole and quadrupole modes in anisotropic formations

    Microsoft Academic Search

    Bikash K. Sinha; Jahir Pabon; Chaur-Jian Hsu

    2003-01-01

    Sonic measurements while drilling are made in the presence of a drill collar (in the form of a thick steel pipe) that provides an additional path for the acoustic energy propagating from the transmitter to an array of receivers. Low-frequency asymptotes of both dipole and quadrupole modes yield the formation far-field shear slowness. Intrinsic or stress-induced anisotropy of surrounding formation

  18. Development of quadrupole mass spectrometers using rapid prototyping technology

    Microsoft Academic Search

    Boris Brki?; Neil France; Adam T. Clare; Chris J. Sutcliffe; Paul R. Chalker; Stephen Taylor

    2009-01-01

    In this report, we present a prototype design of a quadrupole mass filter (QMF) with hyperbolic electrodes, fabricated at\\u000a the University of Liverpool using digital light processing (DLP), a low-cost and lightweight 3D rapid prototyping (RP) technique.\\u000a Experimental mass spectra are shown for H2+, D2+, and He+ ions to provide proof of principle that the DLP mass filter is working

  19. Electrostatic quadrupole array for focusing parallel beams of charged particles

    DOEpatents

    Brodowski, John (Smithtown, NY)

    1982-11-23

    An array of electrostatic quadrupoles, capable of providing strong electrostatic focusing simultaneously on multiple beams, is easily fabricated from a single array element comprising a support rod and multiple electrodes spaced at intervals along the rod. The rods are secured to four terminals which are isolated by only four insulators. This structure requires bias voltage to be supplied to only two terminals and eliminates the need for individual electrode bias and insulators, as well as increases life by eliminating beam plating of insulators.

  20. Radio-frequency quadrupole resonator for linear accelerator

    DOEpatents

    Moretti, A.

    1982-10-19

    An RFQ resonator for a linear accelerator having a reduced level of interfering modes and producing a quadrupole mode for focusing, bunching and accelerating beams of heavy charged particles, with the construction being characterized by four elongated resonating rods within a cylinder with the rods being alternately shorted and open electrically to the shell at common ends of the rods to provide an LC parallel resonant circuit when activated by a magnetic field transverse to the longitudinal axis.

  1. Hybrid permanent magnet quadrupoles for the Recycler Ring at Fermilab

    Microsoft Academic Search

    B. C. Brown; S. M. Pruss; G. W. Foster; H. D. Glass; D. J. Harding; G. R. Jackson; M. R. May; T. H. Nicol; J.-F. Ostiguy; R. Schlabach; J. T. Volk

    1997-01-01

    Hybrid Permanent Magnet Quadrupoles are used in several applications for the Fermilab Recycler Ring and associated beam transfer lines. Most of these magnets use a 0.6096 m long iron shell and provide integrated gradients up to 1.4 T-m\\/m with an iron pole tip radius of 41.6 mm. A 58.4 mm pole radius design is also required. Bricks of 25. 4

  2. Nb3Sn arc quadrupole magnets for VLHC

    Microsoft Academic Search

    Vadim V. Kashikhint; Alexander V. Zlobin

    2001-01-01

    Superconducting quadrupoles with a field gradient of 400-450 T\\/m for a future Very Large Hadron Collider (VLHC) are being studied at Fermilab. To reach the target field gradient in a 40-50 mm aperture, Nb 3Sn superconductor is used at an operating temperature of 4.2 K. Two cases with different magnet functions, beam separation distances and coil arrangements have been analyzed

  3. The PEP-II-Factory septum quadrupole magnets

    SciTech Connect

    Swan, J.M.; Harvey, A.R.; Holmes, R.H.; Kendall, C.M.; Yamamoto, R.M.; Yokota, Ted T. [Lawrence Livermore National Lab., CA (United States); Tanabe, J.T.; Schlueter, R.D. [Lawrence Berkeley Lab., CA (United States)

    1995-06-02

    The PEP-II B-Factory is presently engaged design and fabrication of several unique magnets referred to as septum quadrupoles. This family of magnets is required to contain a low energy beam of positrons (3.1 GeV) and a high energy electron beam (9.0 GeV) in adjacent beam pipes housed within a common magnet. One beam will be focused while the other passes through an almost field free region. To do this, an asymmetric magnet must be designed having a pure, high quality quadrupole field in the magnet aperture and an adjacent low field bypass channel. A current sheet or ``septum`` coil must be placed between these two regions to produce the desired magnetic results. Design of this high current density septum coil presents many challenges since space between the two vacuum beam pipes where the coil must reside is very limited. This paper will describe the overall design of the septum quadrupoles and the solutions employed to achieve the required magnetic performance.

  4. The exact calculation of quadrupole sources for some incompressible flows

    NASA Technical Reports Server (NTRS)

    Brentner, Kenneth S.

    1988-01-01

    This paper is concerned with the application of the acoustic analogy of Lighthill to the acoustic and aerodynamic problems associated with moving bodies. The Ffowcs Williams-Hawkings equation, which is an interpretation of the acoustic analogy for sound generation by moving bodies, manipulates the source terms into surface and volume sources. Quite often in practice the volume sources, or quadrupoles, are neglected for various reasons. Recently, Farassat, Long and others have attempted to use the FW-H equation with the quadrupole source and neglected to solve for the surface pressure on the body. The purpose of this paper is to examine the contribution of the quadrupole source to the acoustic pressure and body surface pressure for some problems for which the exact solution is known. The inviscid, incompressible, 2-D flow, calculated using the velocity potential, is used to calculate the individual contributions of the various surface and volume source terms in the FW-H equation. The relative importance of each of the sources is then assessed.

  5. The exact calculation of quadrupole sources for some incompressible flows

    NASA Astrophysics Data System (ADS)

    Brentner, Kenneth S.

    1988-05-01

    This paper is concerned with the application of the acoustic analogy of Lighthill to the acoustic and aerodynamic problems associated with moving bodies. The Ffowcs Williams-Hawkings equation, which is an interpretation of the acoustic analogy for sound generation by moving bodies, manipulates the source terms into surface and volume sources. Quite often in practice the volume sources, or quadrupoles, are neglected for various reasons. Recently, Farassat, Long and others have attempted to use the FW-H equation with the quadrupole source and neglected to solve for the surface pressure on the body. The purpose of this paper is to examine the contribution of the quadrupole source to the acoustic pressure and body surface pressure for some problems for which the exact solution is known. The inviscid, incompressible, 2-D flow, calculated using the velocity potential, is used to calculate the individual contributions of the various surface and volume source terms in the FW-H equation. The relative importance of each of the sources is then assessed.

  6. Space charge induced nonlinear effects in quadrupole ion traps.

    PubMed

    Guo, Dan; Wang, Yuzhuo; Xiong, Xingchuang; Zhang, Hua; Zhang, Xiaohua; Yuan, Tao; Fang, Xiang; Xu, Wei

    2014-03-01

    A theoretical method was proposed in this work to study space charge effects in quadrupole ion traps, including ion trapping, ion motion frequency shift, and nonlinear effects on ion trajectories. The spatial distributions of ion clouds within quadrupole ion traps were first modeled for both 3D and linear ion traps. It is found that the electric field generated by space charge can be expressed as a summation of even-order fields, such as quadrupole field, octopole field, etc. Ion trajectories were then solved using the harmonic balance method. Similar to high-order field effects, space charge will result in an "ocean wave" shape nonlinear resonance curve for an ion under a dipolar excitation. However, the nonlinear resonance curve will be totally shifted to lower frequencies and bend towards ion secular frequency as ion motion amplitude increases, which is just the opposite effect of any even-order field. Based on theoretical derivations, methods to reduce space charge effects were proposed. PMID:24385397

  7. Particle dynamics in damped nonlinear quadrupole ion traps

    NASA Astrophysics Data System (ADS)

    Vinitsky, Eugene A.; Black, Eric D.; Libbrecht, Kenneth G.

    2015-04-01

    We examine the motions of particles in quadrupole ion traps as a function of damping and trapping forces, including cases where nonlinear damping or nonlinearities in the electric field geometry play significant roles. In the absence of nonlinearities, particles are either damped to the trap center or ejected, while their addition brings about a rich spectrum of stable closed particle trajectories. In three-dimensional (3D) quadrupole traps, the extended orbits are typically confined to the trap axis, and for this case we present a 1D analysis of the relevant equation of motion. We follow this with an analysis of 2D quadrupole traps that frequently show diamond-shaped closed orbits. For both the 1D and 2D cases, we present experimental observations of the calculated trajectories in microparticle ion traps. We also report the discovery of a new collective behavior in damped 2D microparticle ion traps, where particles spontaneously assemble into a remarkable knot of overlapping, corotating diamond orbits, self-stabilized by air currents arising from the particle motion.

  8. 139La nuclear magnetic resonance characterisation of La2O3 and La1-xSrxMO3 where M = Cr, Mn or Co.

    PubMed

    Bastow, T J

    1994-02-01

    139La Nuclear magnetic resonance (NMR) spectra have been used to obtain nuclear quadrupole coupling parameters for La2O3 and a series of perovskites La1-xSrxMO3 (where M = Cr, Mn or Co). Depending on the doping level of SrO2 these materials are either paramagnetic or ferromagnetic at room temperature. Magnetic transferred hyperfine effects are strongly in evidence in the Mn compounds. A 59Co NMR spectrum was observed in LaCoO3. A precision measurement of the nuclear quadrupole coupling constant in La2O3 was made by nuclear quadrupole resonance (NQR) spectroscopy. PMID:7827974

  9. Understanding Interaction

    E-print Network

    Edinburgh, University of

    the interactions · Unconstrained speech recognition · Non-verbal communication · Attention · Social cues · Understanding dialogues · Individual and group behaviour · Multimodal signals, multiparty communication #12;AMIUnderstanding Multiparty Interaction Challenges from Instrumented Meeting Rooms Steve Renals

  10. Understanding Flu

    MedlinePLUS

    ... Navigation Bar Home Current Issue Past Issues Understanding Flu Past Issues / Fall 2006 Table of Contents For ... By Bonny McClain Whether the topic is seasonal influenza, bird flu or something called a pandemic, everyone ...

  11. Understanding Nano

    NSDL National Science Digital Library

    Nanotechnology can be a complicated topic. The Understanding Nano website is dedicated to providing clear and concise explanations of nanotechnology applications along with information on companies working in each area.

  12. Understanding Sarcoidosis

    MedlinePLUS

    ... Register for ENews Home > Lung Disease > Sarcoidosis Understanding Sarcoidosis Sarcoidosis is a disease caused by inflammation. Scientists ... pain, or shortness of breath. How Serious Is Sarcoidosis? Nobody can predict how sarcoidosis will affect one ...

  13. Nuclear Quadrupole Resonance Studies of the Sorc Sequence and Nuclear Magnetic Resonance Studies of Polymers.

    NASA Astrophysics Data System (ADS)

    Jayakody, Jayakody R. Pemadasa

    1993-01-01

    The behavior of induction signals during steady -state pulse irradiation in ^{14} N NQR was investigated experimentally. Because Strong Off-resonance Comb (SORC) signals recur as long as the pulsing continues, very efficient signal-averaging can result. The dependence of these steady-state SORC signals on pulse parameters and on frequency offset are presented, together with a discussion of the applicability of the method. Also as part of the NQR work, Cocaine base has been detected using conventional NQR techniques. The experimental results show that SORC detection can be of sufficient sensitivity to form the basis of narcotics screening devices for both mail and airline baggage. A new NMR technique, to obtain the correlation time of the random thermal motion of a polymer at temperatures near the glass transition has been introduced. The temperature dependence is a result of thermal motion. For slow-motion of a polymer chain near the glass transition, the CSA parameter begins to decrease. This motional narrowing can be interpreted to yield the correlation time of the thermal motion. In this work Nitrocellulose isotopically highly enriched with ^{15}N was studied at four different temperatures between 27^ circ and 120^circ Celsius and the correlation times for polymer backbone motions were obtained. Nafion films containing, water (D_2 O and H_2^{17}O) and methanol (CH_3OD, CH _3^{17}OH), have been studied using Deuteron and Oxygen-17 NMR spectroscopy. Glassy behavior of the water domains at low temperature is evidenced by the specific nature of the ^2H NMR lineshapes. Activation energies extracted from ^2H spin-lattice relaxation data on the high temperature side of the T_1 minimum exhibit a steady increase with increasing water content. In spite of a high degree of molecular mobility, angular-dependent spectra of both unstretched and stretched samples reflect considerable anisotropy of the host polymer. Activation volumes corresponding to a specific dynamical process were obtained from measurements of spin-lattice relaxation vs. pressure. From the NMR measurements of Nafion films containing methanol, it was found that the molecular motion is much more rapid than the molecular motion of water in Nafion membranes.

  14. Nuclear quadrupole resonance studies of the SORC sequence and nuclear magnetic resonance studies of polymers

    SciTech Connect

    Jayakody, J.R.P.

    1993-12-31

    The behavior of induction signals during steady-state pulse irradiation in {sup 14}N NQR was investigated experimentally. Because Strong Off-resonance Comb (SORC) signals recur as long as the pulsing continues, very efficient signal-averaging can result. The dependence of these steady-state SORC signals on pulse parameters and on frequency offset are presented, together with a discussion of the applicability of the method. Also as part of the NQR work, cocaine base has been detected using conventional NQR techniques. The experimental results show that SORC detection can be of sufficient sensitivity to form the basis of narcotics screening devices for both mail and airline baggage. A new NMR technique, to obtain the correlation time of the random thermal motion of a polymer at temperatures near the glass transition has been introduced. The temperature dependence is a result of thermal motion. For slow-motion of a polymer chain near the glass transition, the CSA parameter begins to decrease. This motional narrowing can be interpreted to yield the correlation time of the thermal motion. In this work nitrocellulose isotopically highly enriched with {sup 15}N was studied at four different temperatures between 27{degrees} and 120{degrees} Celsius and the correlation times for polymer backbone motions were obtained. Naflon films containing water (D{sub 2}O and H{sub 2} {sup 17}O) and methanol (CH{sub 3}OD, CH{sub 3} {sup 17}OH), have been studied using deuteron and oxygen-17 NMR spectroscopy. Glassy behavior of the water domains at low temperature is evidenced by the specific nature of the {sup 2}H NMR lineshapes. Activation energies extracted from {sup 2}H spin-lattice relaxation data on the high temperature side of the T{sub 1} minimum exhibit a steady increase with increasing water content. In spite of a high degree of molecular mobility, angular-dependent spectra of both unstretched and stretched samples reflect considerable anisotrophy of the host polymer.

  15. Friction in nuclear dynamics

    SciTech Connect

    Swiatecki, W.J.

    1985-03-01

    The problem of dissipation in nuclear dynamics is related to the breaking down of nuclear symmetries and the transition from ordered to chaotic nucleonic motions. In the two extreme idealizations of the perfectly Ordered Regime and the fully Chaotic Regime, the nucleus should behave as an elastic solid or an overdamped fluid, respectively. In the intermediate regime a complicated visco-elastic behaviour is expected. The discussion is illustrated by a simple estimate of the frequency of the giant quadrupole resonance in the Ordered Regime and by applications of the wall and window dissipation formulae in the Chaotic Regime. 51 refs.

  16. Testing of NB3SN Quadrupole Coils Using Magnetic Mirror Structure

    NASA Astrophysics Data System (ADS)

    Zlobin, A. V.; Andreev, N.; Barzi, E.; Bossert, R.; Chlachidze, G.; Kashikhin, V. S.; Kashikhin, V. V.; Lamm, M. J.; Novitski, I.; Tartaglia, M.; Tompkins, J. C.; Turrioni, D.; Yamada, R.

    2010-04-01

    This paper describes the design and parameters of a quadrupole mirror structure for testing the mechanical, thermal and quench performance of single shell-type superconducting quadrupole coils at field, current and force levels similar to that of real magnet. The concept was experimentally verified by testing two quadrupole coils, previously used in quadrupole models, in the developed mirror structure in the temperature range from 4.5 to 1.9 K. The coils were instrumented with voltage taps, heaters, and strain gauges to monitor their mechanical and thermal properties and quench performance. A new quadrupole coil made of improved Nb3Sn RRP-108/127 strand and cable insulation based on E-glass tape was also tested using this structure. The fabrication and test results of the quadrupole mirror models are reported and discussed.

  17. Bose-Einstein Condensation in an electro-pneumatically transformed quadrupole-Ioffe magnetic trap

    E-print Network

    Sunil Kumar; Sumit Sarkar; Gunjan Verma; Chetan Vishwakarma; Md. Noaman; Umakant Rapol

    2014-08-20

    We report a novel approach for preparing a Bose-Einstein condensate (BEC) of $^{87}$Rb atoms using electro-pneumatically driven transfer of atoms into a Quadrupole-Ioffe magnetic trap (QUIC Trap). More than 5$\\times$$10^{8}$ atoms from a Magneto-optical trap are loaded into a spherical quadrupole trap and then these atoms are transferred into an Ioffe trap by moving the Ioffe coil towards the center of the quadrupole coil, thereby, changing the distance between quadrupole trap center and the Ioffe coil. The transfer efficiency is more than 80 \\%. This approach is different from a conventional approach of loading the atoms into a QUIC trap wherein the spherical quadrupole trap is transformed into a QUIC trap by changing the currents in the quadrupole and the Ioffe coils. The phase space density is then increased by forced rf evaporative cooling to achieve the Bose-Einstein condensation having more than $10^{5}$ atoms.

  18. Bose-Einstein condensation in an electro-pneumatically transformed quadrupole-Ioffe magnetic trap

    NASA Astrophysics Data System (ADS)

    Kumar, Sunil; Sarkar, Sumit; Verma, Gunjan; Vishwakarma, Chetan; Noaman, Md; Rapol, Umakant

    2015-02-01

    We report a novel approach for preparing a Bose–Einstein condensate (BEC) of 87Rb atoms using an electro-pneumatically driven transfer of atoms into a quadrupole-Ioffe magnetic trap (QUIC trap). More than 5 × {{10}8} atoms from a magneto-optical trap are loaded into a spherical quadrupole trap and then transferred into an Ioffe trap by moving the Ioffe coil towards the center of the quadrupole coil thereby changing the distance between the quadrupole trap center and the Ioffe coil. The transfer efficiency is more than 80%. This approach is different from the conventional approach of loading the atoms into a QUIC trap wherein the spherical quadrupole trap is transformed into a QUIC trap by changing the currents in the quadrupole and the Ioffe coils. The phase space density is then increased by forced rf evaporative cooling to achieve Bose–Einstein condensation of more than 105 atoms.

  19. Testing of Nb3Sn quadrupole coils using magnetic mirror structure

    SciTech Connect

    Zlobin, A.V.; Andreev, N.; Barzi, E.; Bossert, R.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.; Novitski, I.; Tartaglia, M.; Tompkins, J.C.; /Fermilab

    2009-07-01

    This paper describes the design and parameters of a quadrupole mirror structure for testing the mechanical, thermal and quench performance of single shell-type superconducting quadrupole coils at field, current and force levels similar to that of real magnet. The concept was experimentally verified by testing two quadrupole coils, previously used in quadrupole models, in the developed mirror structure in the temperature range from 4.5 to 1.9 K. The coils were instrumented with voltage taps, heaters, and strain gauges to monitor their mechanical and thermal properties and quench performance. A new quadrupole coil made of improved Nb{sub 3}Sn RRP-108/127 strand and cable insulation based on E-glass tape was also tested using this structure. The fabrication and test results of the quadrupole mirror models are reported and discussed.

  20. Embodied understanding

    PubMed Central

    Johnson, Mark

    2015-01-01

    Western culture has inherited a view of understanding as an intellectual cognitive operation of grasping of concepts and their relations. However, cognitive science research has shown that this received intellectualist conception is substantially out of touch with how humans actually make and experience meaning. The view emerging from the mind sciences recognizes that understanding is profoundly embodied, insofar as our conceptualization and reasoning recruit sensory, motor, and affective patterns and processes to structure our understanding of, and engagement with, our world. A psychologically realistic account of understanding must begin with the patterns of ongoing interaction between an organism and its physical and cultural environments and must include both our emotional responses to changes in our body and environment, and also the actions by which we continuously transform our experience. Consequently, embodied understanding is not merely a conceptual/propositional activity of thought, but rather constitutes our most basic way of being in, and engaging with, our surroundings in a deep visceral manner. PMID:26175701

  1. Embodied understanding.

    PubMed

    Johnson, Mark

    2015-01-01

    Western culture has inherited a view of understanding as an intellectual cognitive operation of grasping of concepts and their relations. However, cognitive science research has shown that this received intellectualist conception is substantially out of touch with how humans actually make and experience meaning. The view emerging from the mind sciences recognizes that understanding is profoundly embodied, insofar as our conceptualization and reasoning recruit sensory, motor, and affective patterns and processes to structure our understanding of, and engagement with, our world. A psychologically realistic account of understanding must begin with the patterns of ongoing interaction between an organism and its physical and cultural environments and must include both our emotional responses to changes in our body and environment, and also the actions by which we continuously transform our experience. Consequently, embodied understanding is not merely a conceptual/propositional activity of thought, but rather constitutes our most basic way of being in, and engaging with, our surroundings in a deep visceral manner. PMID:26175701

  2. Electric quadrupole transitions in x-ray spectra: 3d transition-metal oxides

    Microsoft Academic Search

    N. V. Dobrodey; Yu. V. Luniakov

    1995-01-01

    The intensities of the electric quadrupole transitions in the x-ray spectra of the 3d-transition-metal monoxide diatomic molecules were calculated using the discrete variational method of the local-density approximation. The quadrupole transition intensities have been found to be negligible for the left-hand-side 3d metal oxides. It was shown that the electric quadrupole transitions can appreciably contribute to the MKbeta5 emission spectra

  3. TDPAC investigations of the111Cd quadrupole interaction in ternary chalcopyrite semiconductors

    NASA Astrophysics Data System (ADS)

    Unterricker, S.; Butz, T.; Tröger, W.

    1991-07-01

    The quadrupole interaction at room temperature of111Cd in CdSiP2, CdGeP2, and CdSnP2 is investigated by111mCd-TDPAC. The results are compared with those of former111In(111Cd) measurements. We observed axially symmetric quadrupole interactions with identical quadrupole coupling constants provided that radiation damage was annealed. This proves that also In probes are positioned at Cd-sites (A-sites) in these ternary compounds.

  4. Stability of the coherent quadrupole oscillations excited by the beam-beam interaction

    SciTech Connect

    Kamiya, Y.; Chao, A.W.

    1983-10-01

    We study the coherent quadrupole motion in the presence of beam-beam interaction, using a linear approximation to the beam-beam force. The corresponding beam-beam limit is determined by evaluating the eigenvalues of a system of linear equations describing the coherent quadrupole motion. We find that the stability of the quadrupole motions imposes severe limits on the beam current, as is the case for the dipole instability. Preliminary results of this study have appeared elsewhere.

  5. Nuclear blackmail and nuclear balance

    SciTech Connect

    Betts, R.K.

    1987-01-01

    This book raises pointed questions about nuclear saber rattling. More than a dozen cases since the bombing of Hiroshima and Magasaki in which some sort of nuclear threat was used as a sparring technique in tense confrontations are cited. Each incident is described and analyzed. Two theories offered to explain America's use of nuclear threats, the balance of interest theory and the balance of power theory, are contrasted throughout the book. This book helps to fill the gap in the understanding of nuclear weapons and their uses, while pointing out that nuclear bravado could lead to an unintended unleashing of these weapons.

  6. Progress in the development of superconducting quadrupoles for heavy ion fusion

    SciTech Connect

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, B.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-05-24

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  7. Progress in the Development of Superconducting Quadrupoles forHeavy-ion Fusion

    SciTech Connect

    Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, R.; Martovetsky, N.; Gung, C.; Minervini, J.; Schultz, J.; Myatt, L.; Meinke, R.

    2002-08-19

    The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.

  8. Comparison of conventional and novel quadrupole drift tube magnets inspired by Klaus Halbach

    SciTech Connect

    Feinberg, B. [Lawrence Berkeley Lab., CA (United States)

    1995-02-01

    Quadrupole drift tube magnets for a heavy-ion linac provide a demanding application of magnet technology. A comparison is made of three different solutions to the problem of providing an adjustable high-field-strength quadrupole magnet in a small volume. A conventional tape-wound electromagnet quadrupole magnet (conventional) is compared with an adjustable permanent-magnet/iron quadrupole magnet (hybrid) and a laced permanent-magnet/iron/electromagnet (laced). Data is presented from magnets constructed for the SuperHILAC heavy-ion linear accelerator, and conclusions are drawn for various applications.

  9. Performance Characteristics of a MEMS Quadrupole Mass Filter With Square Electrodes: Experimental and Simulated Results

    E-print Network

    Hogan, Thomas J.

    Size reduction in quadrupole mass spectrometers (QMSs) is an ongoing requirement driven by the needs of space exploration, portable, and covert monitoring applications. Microelectromechanical systems (MEMS) technology ...

  10. Aperture limitations for 2nd generation Nb3Sn LHC IR quadrupoles

    SciTech Connect

    Alexander V. Zlobin; Vadim V. Kashikhin; James B. Strait

    2003-06-02

    One of the straightforward ways towards the higher luminosity in the LHC is a replacement of the present 70-mm NbTi quadrupoles with Nb{sub 3}Sn quadrupoles which would provide the same field gradient but in a larger aperture. Conceptual designs of such quadrupoles with 90 mm aperture have been developed and studied. This paper discusses the possibilities and limitations of increasing the aperture of Nb{sub 3}Sn low-beta quadrupoles for a LHC luminosity upgrade up to 110 mm.

  11. Design, development, and acceleration trials of radio-frequency quadrupole

    NASA Astrophysics Data System (ADS)

    Rao, S. V. L. S.; Jain, Piyush; Pande, Rajni; Roy, Shweta; Mathew, Jose V.; Kumar, Rajesh; Pande, Manjiri; Krishnagopal, S.; Gupta, S. K.; Singh, P.

    2014-04-01

    A deuteron radio frequency quadrupole (RFQ) accelerator has been designed, fabricated, and tested at BARC, which will be used for neutron generation. The RFQ operates at a frequency of 350 MHz and needs an inter-vane voltage of 44 kV to accelerate the deuteron beam to 400 keV within a length of 1.03 m. The error analysis shows that the offset of two opposite vanes in the same direction by 100 ?m leads to a change in resonant frequency by 1.3 MHz and a significant change of fields in the quadrants (˜±40% with respect to average field). From the 3D analysis, we have observed that the unwanted dipole mode frequencies are very near to the quadrupole mode frequency which will make structure sensitive to the perturbations. In order to move the dipole modes away from the quadrupole modes, we have used the dipole stabilizer rods. The 5 wire transmission line theory was used to study the perturbative analysis of the RFQ and based on this a computer program has been written to tune the cavity to get required field distribution. Based on these studies, a 1.03 m long RFQ made of OFE copper has been fabricated and tested. Even though the RFQ was designed for deuteron (D+) beam, we tested it by accelerating both the proton (H+) and D+ beams. The RFQ was operated in pulsed mode and accelerated both H+ and D+ beams to designed values of 200 and 400 keV, respectively. The measured parameters are in good agreement with the designed values validating our simulations and fabrication processes. In this paper, simulations, RF measurements, and beam commissioning results are presented.

  12. Nuclear astrophysics

    SciTech Connect

    Haxton, W.C.

    1992-12-31

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

  13. Nuclear astrophysics

    SciTech Connect

    Haxton, W.C.

    1992-01-01

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

  14. Understanding Science

    NSDL National Science Digital Library

    University of California Museum of Paleontology

    This page, from University of California Museum of Paleontology, features free, image-rich teaching resources that communicate what science is and how it works, with a focus on the process of science and its dynamic nature. The project is geared toward K-16 teacher preparation as well as broader public understanding of the nature of science.

  15. Understanding Prejudice.

    ERIC Educational Resources Information Center

    Babcock, David

    1967-01-01

    To help students understand prejudice, teachers in Verona, New York, planned a unit which incorporated the use of fiction, television, and film. Students were asked to select and read books in the general area of prejudice. A sample reading list of works under the headings of Negro, Jew, Italian, and Irish was provided. After writing extensive…

  16. Resonance Secondary Radiation enhanced by quadrupole mode of plasmonic arrays

    NASA Astrophysics Data System (ADS)

    Lanterbecq, Déborah; Van Deun, Rik; Morarescu, Rodica; Damman, Pascal; Kolaric, Branko

    2013-11-01

    In this paper, the Resonance Secondary Radiation (RSR), the joined action of the Raman Resonance and Fluorescence emission is described. The observed enhancement of the RSR signal is caused by the quadrupole mode of the plasmonic resonance of gold nanotriangles arrays. The material used in this study has been designed based on two separate nanoscale engineering processes by combining two different materials (oligonucleotides and colloidal arrays) at different length scales. The control of the emission by the plasmonic resonance is demonstrated and thoroughly investigated using extinction, steady state and time-resolved Fluorescence spectroscopy.

  17. Quench margin measurement in Nb3Sn quadrupole magnet

    SciTech Connect

    Kashikhin, V.V.; Bossert, R.; Chlachidze, G.; Lamm, M.; Novitski, I.; Zlobin, A.V.; /Fermilab

    2008-08-01

    One of the possible practical applications of the Nb{sub 3}Sn accelerator magnets is the LHC luminosity upgrade that involves replacing the present NbTi focusing quadrupoles in two high-luminosity interaction regions (IR). The IR magnets are exposed to strong radiation from the interaction point that requires a detailed investigation of the magnet operating margins under the expected radiation-induced heat depositions. This paper presents the results of simulation and measurement of quench limits and temperature margins for a Nb{sub 3}Sn model magnet using a special midplane strip heater.

  18. 2-MV electrostatic quadrupole injector for heavy-ion fusion

    NASA Astrophysics Data System (ADS)

    Bieniosek, F. M.; Celata, C. M.; Henestroza, E.; Kwan, J. W.; Prost, L.; Seidl, P. A.; Friedman, A.; Grote, D. P.; Lund, S. M.; Haber, I.

    2005-01-01

    High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector.

  19. Radio-frequency quadrupole: general properties and specific applications

    SciTech Connect

    Stokes, R.H.; Crandall, K.R.; Hamm, R.W.

    1980-01-01

    The radio-frequency quadrupole (RFQ) linac structure is being developed for the acceleration of low-velocity ions. Recent experimental tests have confirmed its expected performance and have led to an increased interest in a wide range of possible applications. The general properties of RFQ accelerators are reviewed and beam dynamics simulation results are presented for their use in a variety of accelerating systems. These include the low-beta sections of the Fusion Materials Irradiation Test Accelerator, a 200-MHz proton linear accelerator, and a xenon accelerator for heavy ion fusion.

  20. Test of eight superconducting arc quadrupoles for RHIC

    SciTech Connect

    Wanderer, P.; Anerella, M.; Ganetis, G. [and others

    1993-12-31

    Test results from a group of eight superconducting quadrupoles at Brookhaven National Laboratory are presented. The magnets have been designed for use in the arc regions of the Relativistic Heavy Ion Collider now under construction at Brookhaven. Novel features of the design include a single-layer coil, the use of injection-molded phenolic for the pole spacers, and a yoke that also serves as a collar. This R&D series has been used to verify the magnet quench performance and field quality prior to the start of the production run in industry.

  1. Superconducting focusing quadrupoles for heavy ion fusion experiments

    SciTech Connect

    Sabbi, G.L.; Faltens, A.; Leitner, M.; Lietzke, A.; Seidl, P.; Barnard, J.; Lund, S.; Martovetsky, N.; Gung, C.; Minervini, J.; Radovinsky, A.; Schultz, J.; Meinke, R.

    2003-05-01

    The Heavy Ion Fusion (HIF) Program is developing superconducting focusing magnets for both near-term experiments and future driver accelerators. In particular, single bore quadrupoles have been fabricated and tested for use in the High Current Experiment (HCX) at Lawrence Berkeley National Laboratory (LBNL). The next steps involve the development of magnets for the planned Integrated Beam Experiment (IBX) and the fabrication of the first prototype multi-beam focusing arrays for fusion driver accelerators. The status of the magnet R&D program is reported, including experimental requirements, design issues and test results.

  2. Electrostatic quadrupole accelerator for the heavy ion fusion project

    SciTech Connect

    Henestroza, E.; Yu, S.; Eylong, S. [Lawrence Berkeley Lab., CA (United States)

    1994-12-31

    A full scale (2 MeV, 800 mA, K{sup +}), low emittance injector for the Heavy Ion Fusion Project has been built at LBL. It consists of a 700 keV diode pre-injector followed by an electrostatic quadrupole accelerator (ESQ) which provides strong focusing for the space-charge dominated beam and simultaneously accelerates the ions to 2 MeV. The actual operation of this new machine has exceeded design parameters. Design of the accelerator, report on experiments performed in connection with the evaluation and characterization of the ESQ and corresponding 3D Particle in Cell simulations will be presented.

  3. Scaling laws for aberrations in magnetic quadrupole lens systems

    SciTech Connect

    Moses, R.W.; Heighway, E.A.; Christian, R.S.; Dragt, A.J.

    1987-01-01

    A comparison has been made of the third-order (spherical) abberrations in magnetic quadrupole lenses for use in conventional charged particle beam transport systems. An analytical description of the abberrations is presented and this is compared with the results of high order numerical integration. The dependence of the aberration strength on the system geometry and f number is given and a comparison of doublet and triplet systems made. The reduction of the aberrations in both doublet and triplet systems using embedded magnetic octupole lenses is also discussed and analytical predictions are given.

  4. Tests of high gradient superconducting quadrupole magnets for the Tevatron

    SciTech Connect

    Lamm, M.J.; Carson, J.; Gourlay, S.; Hanft, R.; Koepke, K.; Mantsch, P.; McInturff, A.D.; Riddiford, A.; Strait, J.

    1989-09-01

    Tests have been completed on three prototype magnets and two production magnets to be used for the Tevatron D{phi}/B{phi} low- {beta} insertion. These cold iron, two shell quadrupoles are made of 36 strand Rutherford type NbTi superconducting cable. Magnet field gradients well in excess of the design 1.41 T/cm have been achieved at a transfer function of 0.291 T/cm/kA. Quench performance at 4.2 K and 3.7 K and magnetic multipole measurement data are presented and discussed. 9 refs., 4 figs., 4 tabs.

  5. Optically plugged quadrupole trap for Bose-Einstein condensates

    SciTech Connect

    Naik, D.S.; Raman, C. [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2005-03-01

    We created sodium Bose-Einstein condensates in an optically plugged quadrupole magnetic trap. A focused, 532-nm laser beam repelled atoms from the coil center where Majorana loss is significant. We produced condensates containing up to 3x10{sup 7} atoms, a factor of 60 improvement over previous work and a number comparable to the best all-magnetic traps, and transferred up to 9x10{sup 6} atoms into a purely optical trap. We compare our observations with a simple model of evaporative cooling, concluding that a laser in the range of 1 W (rather than 5 W) may suffice.

  6. Miniature quadrupole mass spectrometer having a cold cathode ionization source

    DOEpatents

    Felter, Thomas E. (Livermore, CA)

    2002-01-01

    An improved quadrupole mass spectrometer is described. The improvement lies in the substitution of the conventional hot filament electron source with a cold cathode field emitter array which in turn allows operating a small QMS at much high internal pressures then are currently achievable. By eliminating of the hot filament such problems as thermally "cracking" delicate analyte molecules, outgassing a "hot" filament, high power requirements, filament contamination by outgas species, and spurious em fields are avoid all together. In addition, the ability of produce FEAs using well-known and well developed photolithographic techniques, permits building a QMS having multiple redundancies of the ionization source at very low additional cost.

  7. Nb{sub 3}Sn ARC quadrupole magnets for VLHC

    SciTech Connect

    Vadim V. Kashikhin and Alexander V. Zlobin

    2001-07-30

    Superconducting quadrupoles with a field gradient of 400-450 T/m for a future Very Large Hadron Collider (VLHC) are being studied at Fermilab. To reach the target field gradient in a 40-50 mm aperture, Nb{sub 3}Sn superconductor is used at an operating temperature of 4.2 K. Two cases with different magnet functions, beam separation distances and coil arrangements have been analyzed and optimized in order to provide the required field quality and magnet parameters.

  8. Single layer quadrupole design for SSC (Superconducting Super Collidar)

    SciTech Connect

    Thompson, P.A.; Cottingham, J.; Dahl, P.; Garber, M.; Ghosh, A.; Goodzeit, C.; Greene, A.; Hahn, H.; Herrera, J.; Kahn, S.

    1987-01-01

    The proposed Superconducting Super Collider (SSC) will require 1360 regular arc quadrupoles. This paper describes a single layer design for these magnets. This design is economically competitive with the more conventional two layer design and appears to be well suited to mass production because of its simplicity. The design uses 9 turns of Cu(NbTi) superconducting cable to produce an 155 Tesla/meter gradient at the 20 TeV peak energy. The systematic field harmonics are all better than the requirements. Detailed results of both magnetic and mechanical analyses are presented.

  9. Finding the Magnetic Center of a Quadrupole to High Resolution

    SciTech Connect

    Fischer, G.E.; Cobb, J.K.; Jenson, D.R.; /SLAC

    2005-08-12

    In a companion pro, collposal it is proposed to align quadrupoles of a transport line to within transverse tolerances of 5 to 10 micrometers. Such a proposal is meaningful only if the effective magnetic center of such lenses can in fact be repeatably located with respect to some external mechanical tooling to comparable accuracy. It is the purpose of this note to describe some new methods and procedures that will accomplish this aim. It will be shown that these methods are capable of yielding greater sensitivity than the more traditional methods used in the past. The notion of the ''nodal'' point is exploited.

  10. Nuclear chemistry research and spectroscopy with radioactive sources. Twentieth annual progress report, September 1, 1983-August 31, 1984

    SciTech Connect

    Fink, R.W.

    1984-08-31

    Research under this continuing DOE contract centers on radioactive decay studies of nuclei far from stability produced with heavy ions from the Holifield Heavy Ion Research Facility (HHIRF) and studied on-line with the University Isotope Separator at Oak Ridge (UNISOR). These investigations encompass three aspects of nuclear structure research: nuclear spectroscopic measurements involving detailed ..gamma gamma..t, ..gamma..e/sup -/t, and X..gamma..t three-parameter coincidence spectrometry; on-line laser hyperfine structure (hfs) and isotope shift spectroscopy for determining quadrupole moments, nuclear spins, and mean nuclear charge radii; and computer calculations of nuclear model predictions for comparison with the experimental level schemes. The focus of this research program is on odd-mass nuclei in which the odd nucleon probes the core, making possible observation of such phenomena as the onset of abrupt shape changes, the occurrence of shape coexistence, and shell-model intruder states. These phenomena are critical tests of concepts fundamental to an understanding of low-energy nuclear structure, such as nuclear deformations, shell models, collective models, and particle-core couplings.

  11. Understanding Boston

    NSDL National Science Digital Library

    How does one begin to understand the workings of a major metropolis? It can be a tough job even for a seasoned expert in urbanology or governance. The Boston Foundation has offered up this area of its website to bring together resources that address the thorniest issues facing the Hub, including public schools, public health, transportation, and housing costs. First up is the Research, Reports, and Forums area, which includes working papers on public health throughout the region, links to the Greater Boston Indicator database, and information about changing models of urban governance throughout the region. The site also includes a group of areas dedicated to Understanding Boston that include Civic Engagement, Community Safety, and Cultural Vitality. Within each of these areas, visitors can look over working papers, read about upcoming events and conferences, and learn about the Foundation's long range plans.

  12. Understanding Drought

    NSDL National Science Digital Library

    COMET

    2009-02-11

    Understanding Drought--This webcast provides an introduction to drought. It presents the measures and scales of drought and how drought is monitored. It also covers how drought is predicted, the impacts of drought, and provides information about drought-related resources. This content serves as a foundation to learning more about climate variability and operational climate services and prepares users for the national implementation of NIDIS. This module was last updated on Sept 28, 2009.

  13. Nucleon polarization and the nuclear charge operator

    Microsoft Academic Search

    D. Drechsel; L. Tiator; M. Beyer; M. M. Giannini

    1982-01-01

    Effects of nucleon polarization on the nuclear charge operator have been evaluated in a constituent quark model. At momentum transfer q ~ 4 fm-1 monopole, dipole and quadrupole excitations are of equal importance. In a harmonic oscillator model for 3He all multipolarities give negative contributions, leading to an overall contribution comparable to the relativistic pair effect. The influence of realistic

  14. Inertial Parameters for Collective Nuclear Oscillations

    Microsoft Academic Search

    Steven A. Moszkowski

    1956-01-01

    Inertial parameters for nuclear rotation and quadrupole shape oscillation are known to be several times as large as the values assuming irrotational flow. These parameters may be calculated by using a method due to Inglis and applied in recent work by Bohr and Mottelson. The nucleus is assumed to be mainly in the lowest possible intrinsic state, but slightly perturbed

  15. Testing Understanding and Understanding Testing.

    ERIC Educational Resources Information Center

    Pedersen, Jean; Ross, Peter

    1985-01-01

    Provides examples in which graphs are used in the statements of problems or in their solutions as a means of testing understanding of mathematical concepts. Examples (appropriate for a beginning course in calculus and analytic geometry) include slopes of lines and curves, quadratic formula, properties of the definite integral, and others. (JN)

  16. Quadrupole moments of rotating neutron stars and strange stars

    E-print Network

    Urbanec, Martin; Stuchlik, Zdenek

    2013-01-01

    We present results for models of neutron stars and strange stars constructed using the Hartle-Thorne slow-rotation method with a wide range of equations of state, focusing on the values obtained for the angular momentum $J$ and the quadrupole moment $Q$, when the gravitational mass $M$ and the rotational frequency $\\Omega$ are specified. Building on previous work, which showed surprising uniformity in the behaviour of the moment of inertia for neutron-star models constructed with widely-different equations of state, we find similar uniformity for the quadrupole moment. These two quantities, together with the mass, are fundamental for determining the vacuum space-time outside neutron stars. We study particularly the dimensionless combination of parameters $QM/J^2$ (using units for which $c=G=1$). This quantity goes to 1 in the case of a Kerr-metric black hole and deviations away from 1 then characterize the difference between neutron-star and black-hole space-times. It is found that $QM/J^2$ for both neutron s...

  17. Performance of Nb3Sn Quadrupole Under High Stress

    SciTech Connect

    Felice, H.; Bajko, M.; Bingham, B.; Bordini, B.; Bottura, L.; Caspi, S.; Rijk, G. De; Dietderich, D.; Ferracin, P.; Giloux, C.; Godeke, A.; Hafalia, R.; Milanese, A.; Rossi, L.; Sabbi, G. L.

    2010-08-01

    Future upgrades of the Large Hadron Collider (LHC) will require large aperture and high gradient quadrupoles. Nb{sub 3}Sn is the most viable option for this application but is also known for its strain sensitivity. In high field magnets, with magnetic fields above 12 T, the Lorentz forces will generate mechanical stresses that may exceed 200 MPa in the windings. The existing measurements of critical current versus strain of Nb{sub 3}Sn strands or cables are not easily applicable to magnets. In order to investigate the impact of high mechanical stress on the quench performance, a series of tests was carried out within a LBNL/CERN collaboration using the magnet TQS03 (a LHC Accelerator Research Program (LARP) 1-meter long, 90-mm aperture Nb{sub 3}Sn quadrupole). The magnet was tested four times at CERN under various pre-stress conditions. The average mechanical compressive azimuthal pre-stress on the coil at 4.2 K ranged from 120 MPa to 200 MPa. This paper reports on the magnet performance during the four tests focusing on the relation between pre-stress conditions and the training plateau.

  18. Compressive mass analysis on quadrupole ion trap systems.

    PubMed

    Chen, Evan Xuguang; Gehm, Michael; Danell, Ryan; Wells, Mitch; Glass, Jeffrey T; Brady, David

    2014-07-01

    Conventionally, quadrupole ion trap mass spectrometers eject ions of different mass-to-charge ratio (m/z) in a sequential fashion by performing a scan of the rf trapping voltage amplitude. Due to the inherent sparsity of most mass spectra, the detector measures no signal for much of the scan time. By exploiting this sparsity property, we propose a new compressive and multiplexed mass analysis approach--multi Resonant Frequency Excitation (mRFE) ejection. This new approach divides the mass spectrum into several mass subranges and detects all the subrange spectra in parallel for increased mass analysis speed. Mathematical estimation of standard mass spectrum is demonstrated while statistical classification on the parallel measurements remains viable because of the sparse nature of the mass spectra. This method can reduce mass analysis time by a factor of 3-6 and increase system duty cycle by 2×. The combination of reduced analysis time and accurate compound classification is demonstrated in a commercial quadrupole ion trap (QIT) system. PMID:24806048

  19. Quadrupole Approximation for Para-Positronium in Relativistic Schrödinger Theory

    E-print Network

    M. Mattes; M. Sorg

    2011-09-11

    The non-relativistic energy levels of para-positronium are calculated in the quadrupole approximation of the interaction potential. This approximation technique takes into account the anisotropy of the electrostatic electron-positron interaction in the lowest order. The states due to different values of the quantum number $(l_z)$ of angular momentum are found to be no longer degenerate as is the case in the conventional theory. The physical origin of this elimination of the conventional degeneracy may intuitively be attributed to the state-dependent inertial \\emph{broadening} of the rotating charge clouds; the corresponding \\emph{anisotropic} deformation (in the quadrupole approximation) lowers then the negative electrostatic interaction energy. The result of this influence of anisotropy is that the states with $l_z=0$ adopt smaller binding energy whereas the states with maximal value of $|l_z|$ (for fixed principal quantum number $n$) have the largest binding energy within the angular momentum multiplet $(-|l_{z,\\mathrm{max}}| \\le l_z \\le |l_{z,\\mathrm{max}}|)$. This yields a certain kind of electric fine-structure splitting with the splitted RST levels being placed in a relatively narrow band around the (highly degenerated) conventional levels.

  20. The quadrupole model for rigid-body gravity simulations

    NASA Astrophysics Data System (ADS)

    Dobrovolskis, Anthony R.; Korycansky, D. G.

    2013-07-01

    We introduce two new models for gravitational simulations of systems of non-spherical bodies, such as comets and asteroids. In both models, one body (the "primary") may be represented by any convenient means, to arbitrary accuracy. In our first model, all of the other bodies are represented by small gravitational "molecules" consisting of a few point masses, rigidly linked together. In our second model, all of the other bodies are treated as point quadrupoles, with gravitational potentials including spherical harmonic terms up to the third degree (rather than only the first degree, as for ideal spheres or point masses). This quadrupole formulation may be regarded as a generalization of MacCullagh's approximation. Both models permit the efficient calculation of the interaction energy, the force, and the torque acting on a small body in an arbitrary external gravitational potential. We test both models for the cases of a triaxial ellipsoid, a rectangular parallelepiped, and "duplex" combinations of two spheres, all in a point-mass potential. These examples were chosen in order to compare the accuracy of our technique with known analytical results, but the ellipsoid and duplex are also useful models for comets and asteroids. We find that both approaches show significant promise for more efficient gravitational simulations of binary asteroids, for example. An appendix also describes the duplex model in detail.

  1. Adjustable Permanent Quadrupoles for the Next Linear Collider

    NASA Astrophysics Data System (ADS)

    Spencer, C. M.

    2001-10-01

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to 20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. In an effort to reduce costs and increase reliability, several designs using hybrid permanent magnets have been developed. Four different prototypes have been built. All magnets have iron poles and use Samarium Cobalt to provide the magnetic fields. Two use rotating permanent magnetic material to vary the gradient, one uses a sliding shunt to vary the gradient and the fourth uses counter rotating magnets. Preliminary data on gradient strength, temperature stability, and magnetic center position stability are presented. These data are compared to an equivalent electromagnetic prototype.

  2. Adjustable permanent quadrupoles for the next linear collider

    SciTech Connect

    James T. Volk et al.

    2001-06-22

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to {minus}20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. In an effort to reduce costs and increase reliability, several designs using hybrid permanent magnets have been developed. Four different prototypes have been built. All magnets have iron poles and use Samarium Cobalt to provide the magnetic fields. Two use rotating permanent magnetic material to vary the gradient, one uses a sliding shunt to vary the gradient and the fourth uses counter rotating magnets. Preliminary data on gradient strength, temperature stability, and magnetic center position stability are presented. These data are compared to an equivalent electromagnetic prototype.

  3. Understanding Evolution

    NSDL National Science Digital Library

    The intent of this website is to give teachers a background understanding of evolution, opening the door by giving them strategies for teaching and responding to misconceptions and roadblocks. The heart of the site is Evolution 101, which can serve as a primer to evolutionary theory or an intensive course in the nitty gritty details of speciation, micro- and macroevolution, and ongoing research into how evolution happens. The site is replete with practical examples of how evolution impacts our daily lives, including lesson plans about bunny breeding, the problem of antibiotic resistance in disease organisms, and the conservation and breeding of endangered species.

  4. Ion Trap/Ion Mobility/Quadrupole/Time-of-Flight Mass Spectrometry for Peptide Mixture Analysis

    E-print Network

    Clemmer, David E.

    Ion Trap/Ion Mobility/Quadrupole/Time-of-Flight Mass Spectrometry for Peptide Mixture Analysis IN, 47405 An ion trap/ion mobility/quadrupole/time-of-flight mass spectrometer has been developed tube where ions separate ac- cording to differences in gas-phase ion mobilities. Upon exiting the drift

  5. Application of an explosive detection device based on quadrupole resonance (QR) technology in aviation security

    Microsoft Academic Search

    Ed Rao; William J. Hughes

    2001-01-01

    The Federal Aviation Administration has deployed Advanced Technology (AT) based explosive detection devices for screening checked baggage in US domestic airports. The paper addresses the application of quadrupole resonance (QR) technology to detect explosives in checked baggage in aviation security. This technology was deployed in combination with advanced X-ray by the US government. The paper focuses on the quadrupole resonance

  6. COMPARISON OF PRIORITY POLLUTANT RESPONSE FACTORS FOR TRIPLE AND SINGLE QUADRUPOLE MASS SPECTROMETERS

    EPA Science Inventory

    Seventy-four percent of the electron impact GC/MS response factors (RF) determined on a triple quadrupole mass spectrometer for 53 extractable priority pollutants were found to be within + or - 15 percent of values determined in an independent interlaboratory single quadrupole GC...

  7. Effects of extreme magnetic quadrupole fields on penning traps and the consequences for antihydrogen trapping.

    PubMed

    Fajans, J; Bertsche, W; Burke, K; Chapman, S F; van der Werf, D P

    2005-10-01

    Measurements on electrons confined in a Penning trap show that extreme quadrupole fields destroy particle confinement. Much of the particle loss comes from the hitherto unrecognized ballistic transport of particles directly into the wall. The measurements scale to the parameter regime used by ATHENA and ATRAP to create antihydrogen, and suggest that quadrupoles cannot be used to trap antihydrogen. PMID:16241731

  8. SECOND GENERATION HIGH GRADIENT QUADRUPOLES FOR THE LHC INTERACTION REGIONS1

    E-print Network

    Large Hadron Collider Program

    . A quadrupole with a 90 mm coil aperture and the same 200 T/m gradient as in the current LHC IR is technically a nominal field gradient of 200 T/m at the high luminosity insertions with 70-mm coils, and operate at 1.9KSECOND GENERATION HIGH GRADIENT QUADRUPOLES FOR THE LHC INTERACTION REGIONS1 T. Sen, J. Strait

  9. Measuring the Magnetic Center Behavior of an ILC Superconducting Quadrupole Prototype

    SciTech Connect

    Spencer, Cherrill M.; Adolphsen, Chris; Berndt, Martin; Jensen, David R.; Rogers, Ron; Sheppard, John C.; Lorant, Steve St; Weber, Thomas B.; Weisend, John, II; /SLAC; Brueck, Heinrich; /DESY; Toral, Fernando; /Madrid, CIEMAT

    2011-02-07

    The main linacs of the proposed International Linear Collider (ILC) consist of superconducting cavities operated at 2K. The accelerating cavities are contained in a contiguous series of cryogenic modules that also house the main linac quadrupoles, thus the quadrupoles also need to be superconducting. In an early ILC design, these magnets are about 0.6 m long, have cos (2{theta}) coils, and operate at constant field gradients up to 60 T/m. In order to preserve the small beam emittances in the ILC linacs, the e+ and e- beams need to traverse the quadrupoles near their magnetic centers. A quadrupole shunting technique is used to measure the quadrupole alignment with the beams; this process requires the magnetic centers move by no more than about 5 micrometers when their strength is changed. To determine if such tight stability is achievable in a superconducting quadrupole, we at SLAC measured the magnetic center motions in a prototype ILC quadrupole built at CIEMAT in Spain. A rotating coil technique was used with a better than 0.1 micrometer precision in the relative field center position, and less than a 2 micrometer systematic error over 30 minutes. This paper describes the warm-bore cryomodule that houses the quadrupole in its Helium vessel, the magnetic center measurement system, the measured center data and strength and harmonics magnetic data.

  10. Impact of Quadrupole offset and Undulator end-kicks on the

    E-print Network

    [5, 6, 7, 8]. Therefore, in this report we study the quadrupole offset and undulator end-kick due kicked due to gap dependent end fields with a similar impact. In this report, the effect of bothImpact of Quadrupole offset and Undulator end-kicks on the European-XFEL facility Performance Yuhui

  11. Adjustable permanent quadrupoles using rotating magnet material rods for the Next Linear Collider

    Microsoft Academic Search

    J. DiMarco; G. W. Foster; W. Fowler; V. S. Kashikhin; A. Makarov; C. E. Rago; A. Ringwall; C. M. Spencer; V. Tsvetkov; J. T. Volk; Z. Wolf

    2002-01-01

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 132 Tesla, with a maximum gradient of 135 Tesla per meter, an adjustment range of +0 -20% and effective lengths from 324 mm to 972 mm. The

  12. Design and Manufacture of a Hybrid Final Focus Quadrupole Model for CLIC

    Microsoft Academic Search

    Alexey Vorozhtsov; Michele Modena; Davide Tommasini

    2012-01-01

    A tunable hybrid quadrupole magnet design has been proposed for the final focus in the Compact Linear Collider (CLIC) that is currently under study. The proposed design is a combination of an iron dominated electromagnetic quadrupole with a bore diameter of 8.25 mm with permanent magnet blocks placed between the poles made of soft magnetic CoFe alloy “Permendur”. The possibility

  13. Adjustable Permanent Quadrupoles Using Rotating Magnet Material Rods for the Next Linear Collider

    Microsoft Academic Search

    Cherrill M

    2002-01-01

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 132 Tesla, with a maximum gradient of 135 Tesla per meter, an adjustment range of +0 -20% and effective lengths from 324 mm to 972 mm. The

  14. Understanding ayurveda.

    PubMed

    Gadgil, Vaidya Dilip

    2010-01-01

    Ayurveda needs to achieve its full potential both in India and globally. This requires imparting to its students full appreciation of Ayurveda's power and strength, particularly proper understanding of the advantages of applying it to treat chronic and acute diseases. To this end, we explain the necessity of learning Sanskrit as a medium of study, and the advantages of learning the Texts in the traditional way, rather than relying on translations with all the loss of meaning and precision, which that entails. We emphasize the use of Triskandhakosha as a means to fully understand Ayurveda fundamental concepts and technical terms, so that all their shades of meaning are fully understood, and all their usages given in different places in the texts. Only by such methods can full appreciation of Ayurvedic wisdom be achieved, and the full depth and power of its knowledge be applied. Only then will its true status among systems of medicine come to be appreciated, either in India or more widely in the world as a whole. PMID:21829307

  15. Test Results of a Superconducting Quadrupole Model Designed for Linear Accelerator Applications

    SciTech Connect

    Kashikhin, Vladimir S.; Andreev, Nikolai; Chlachidze, Guram; DiMarco, Joseph; Kashikhin, Vadim V.; Lamm, Michael J.; Lopes, Mauricio L.; Orris, Darryl; Tartaglia, Michael; Tompkins, John C.; Velev, Gueorgui; /Fermilab

    2008-08-01

    The first model of a superconducting quadrupole for use in a Linear Accelerator was designed, built and tested at Fermilab. The quadrupole has a 78 mm aperture, and a cold mass length of 680 mm. A superferric magnet configuration with iron poles and four racetrack coils was chosen based on magnet performance, cost, and reliability considerations. Each coil is wound using enamel insulated, 0.5 mm diameter, NbTi superconductor. The quadrupole package also includes racetrack type dipole steering coils. The results of the quadrupole design, manufacturing and test, are presented. Specific issues related to the quadrupole magnetic center stability, superconductor magnetization and mechanical stability are discussed. The magnet quench performance and results of magnetic measurements will also be briefly discussed.

  16. Understanding Leukemias

    NSDL National Science Digital Library

    Braun, Mark

    This tutorial is designed to aid medical students at all levels understand the laboratory diagnosis of leukemias. It includes introductory material on the basic laboratory tests specific to diagnoses, their general application and pitfalls in interpretation. The introductory material is followed by a series of short clinical vignettes illustrating the major categories of leukemia. This tutorial focuses on diagnosis and relative little on treatment is included. QuickTime movie player, Flash player and Java script runtime plug-in scripts are required for some pages. The tutorial concludes with a short self-help quiz covering the major points developed. The plug-ins noted above are available free at the following sites: http://www.apple.com/quicktime/download/win.html and http://www.sun.com/ . Questions should be directed to Dr. Mark Braun; braunm@indiana.edu.Annotated: falseDisease diagnosis: neoplastic

  17. Understanding Life

    NSDL National Science Digital Library

    Understanding Life is the educational website of The Physiological Society, providing "support for the teaching and learning of physiology." A good place to start is the What is Physiology? area, which offers an overview of this field of human inquiry. The Resources area is a well-designed archive of instructional materials that include "The story of a single heartbeat," "The Science of Life," and "Planning an experiment." It's worth noting that visitors can create their own accounts on the site so they can receive specialized newsletters, tailored website content, and become eligible to enter scientific competitions. Moving along, the Events area lists important goings-on that will be of interest to educators and those involved with science pedagogy. [KMG

  18. Powder MAS NMR lineshapes of quadrupolar nuclei in the presence of second-order quadrupole interaction.

    PubMed

    Ajoy, G; Ramakrishna, J; Bahçeli, S; Klinowski, J

    2000-07-01

    We derive a complete analytical solution for the powder magic angle spinning (MAS) nuclear magnetic resonance (NMR) lineshape in the presence of second-order quadrupole interaction, considering a radiofrequency (rf) pulse of finite width, a finite MAS frequency, and a non-zero asymmetry parameter. (Ix) is calculated using two approaches. The first applies time-dependent perturbation theory in the presence of the rf pulse and stationary perturbation theory (SPT) in its absence. The second is based on the Magnus expansion of the density matrix in the interaction representation during the pulse and SPT in its absence. We solve the problem in the laboratory frame using the properties of the Fourier transform and spin operators. Diagonalisation is not required. Both approaches agree well with each other under all conditions and also with the transition probability approach for the central transition. The Magnus expansion exists at all times and the effect of the non-secular terms is negligible. We describe an analytical method of averaging (Ix) over the Euler angles and simulate the 11B MAS NMR lineshapes for crystalline and vitreous B2O3. A critical analysis is given of all earlier calculations of the MAS NMR lineshape. PMID:10928635

  19. Abstract--A Modular Design and Modular Program is introduced here for high gradient quadrupoles. The proposed

    E-print Network

    Gupta, Ramesh

    high gradient quadrupole designs using flat racetrack coils have been considered earlier, they have creates a gradient in flat racetrack coils quadrupoles that is close to the gradient that is achieved. In such designs, turns at midplane are away from the coil radius. Very high gradient quadrupoles, such as those

  20. Abstract--The development of insertion quadrupoles with 205 T/m gradient and 90 mm bore represents a promising

    E-print Network

    Large Hadron Collider Program

    is needed in order to achieve high gradient. The required coil thickness for this application is about 30 mm2LC03 1 Abstract-- The development of insertion quadrupoles with 205 T/m gradient and 90 mm bore Hadron Collider, Quadrupole, Superconducting Magnets. I. INTRODUCTION IGH gradient NbTi quadrupoles

  1. Shell model calculations of B (E2) values, static quadrupole moments, and g factors for a number of N =Z nuclei

    NASA Astrophysics Data System (ADS)

    Robinson, S. J. Q.; Hoang, T.; Zamick, L.; Escuderos, A.; Sharon, Y. Y.

    2014-01-01

    In this work we look at the low-lying nuclear structure properties of several N =Z nuclei residing between the doubly magic nuclei 40Ca and 100Sn. Using large shell model codes, we calculate and discuss the systematics of energies. We show energy levels, B (E2)'s, static quadrupole moments, and g factors of these N =Z nuclei. In all cases, we compare the results of two different interactions which yield significantly different occupation numbers. We compare our shell model results with those of the rotational and vibrational models. By examining B (E2)'s and static quadrupole moments, we make associations with collective models and find that in the model space considered here, 88Ru is oblate. The quadrupole moment of the lowest 2+state of 92Pd is calculated to be very small. This would appear to support a vibrational picture and indeed recent measurements give equally spaced levels up to J =6+ but the authors also point out that the B (E2)'s do not steadily increase as is required by such a model.

  2. Investigation of a quadrupole ultra-high vacuum ion pump

    NASA Technical Reports Server (NTRS)

    Schwarz, H. J.

    1974-01-01

    The new nonmagnetic ion pump resembles the quadrupole ionization gage. The dimensions are larger, and hyperbolically shaped electrodes replace the four rods. Their surfaces follow y sq. = 36 + x sq. (x, y in centimeters). The electrodes, 55 cm long, are positioned lengthwise in a tube. At one end a cathode emits electrons; at the other end a narrowly wound flat spiral of tungsten clad with titanium on cathode potential can be heated for titanium evaporation. Electrons accelerated by a dc potential of the surface electrodes oscillate between the ends on rotational trajectories, if a high frequency potential superimposed on the dc potential is properly adjusted. Pumping speeds (4-100 liter/sec) for different gases at different peak voltages (1000-3000V) at corresponding frequencies (57-100 MHz), and at different pressures 0.00001 to the minus 9 power Torr were observed. The lowest pressure reached was below 10 to the minus 10 power Torr.

  3. Thermal noise in aqueous quadrupole micro- and nano-traps

    PubMed Central

    2012-01-01

    Recent simulations and experiments with aqueous quadrupole micro-traps have confirmed a possibility for control and localization of motion of a charged particle in a water environment, also predicting a possibility of further reduction of the trap size to tens of nano-meters for trapping charged bio-molecules and DNA segments. We study the random thermal noise due to Brownian motion in water which significantly influences the trapping of particles in an aqueous environment. We derive the exact, closed-form expressions for the thermal fluctuations of position and velocity of a trapped particle and thoroughly examine the properties of the rms for the fluctuations as functions of the system parameters and time. The instantaneous signal transferring mechanism between the velocity and position fluctuations could not be achieved in the previous phase-average approaches. PMID:22369362

  4. Plasma-beam traps and radiofrequency quadrupole beam coolers

    SciTech Connect

    Maggiore, M., E-mail: mario.maggiore@lnl.infn.it; Cavenago, M.; Comunian, M.; Chirulotto, F.; Galatà, A.; De Lazzari, M.; Porcellato, A. M.; Roncolato, C.; Stark, S. [INFN-LNL, viale dell’Università 2, 35020 Legnaro (Italy)] [INFN-LNL, viale dell’Università 2, 35020 Legnaro (Italy); Caruso, A.; Longhitano, A. [INFN-LNS, via S. Sofia 54, 95123 Catania (Italy)] [INFN-LNS, via S. Sofia 54, 95123 Catania (Italy); Cavaliere, F.; Maero, G.; Paroli, B.; Pozzoli, R.; Romé, M. [INFN Sezione di Milano and Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)] [INFN Sezione di Milano and Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano (Italy)

    2014-02-15

    Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

  5. Restoring the skew quadrupole moment in the Tevatron dipoles

    SciTech Connect

    Harding, D.J.; Bauer, P.C.; Blowers, J.N.; DiMarco, J.; Glass, H.D.; Hanft, R.W.; Carson, J.A.; Robotham, W.F.; Tartaglia, M.A.; Tompkins, J.C.; Velev, G.; /Fermilab

    2005-05-01

    In early 2003 it was realized that mechanical changes in the Tevatron dipoles had led to a deterioration of the magnetic field quality that was hindering operation of the accelerator. After extensive study, a remediation program was started in late 2003 that will continue through 2005. The mechanical and magnetic effects are discussed. The readjustment process and experience are reported, along with other observations on aging magnets. In January 2003 two lines of inquiry converged, leading to the recognition that the severe betatron coupling that was hindering operation of the Tevatron could be explained by a systematic shift on the skew quadrupole field in the dipole magnets of the same size expected from observed mechanical movement of the coils inside the magnet yokes [1]. This paper reports on subsequent magnet studies that were conducted in parallel with additional beam studies and accelerator modeling [2] exploring the feasibility of the eventual remediation effort [3].

  6. Guidelines for the design of very large aperture quadrupole magnets

    SciTech Connect

    Daeel, A.; Jorda, J.P.; Kircher, F.; Mayri, C. [CEA-DSM/DAPNIA, Gif-sur-Yvette (France). Service Technique de Cryogenie et de Magnetisme] [CEA-DSM/DAPNIA, Gif-sur-Yvette (France). Service Technique de Cryogenie et de Magnetisme

    1996-07-01

    Very large aperture quadrupole magnets have been recently considered as possible spectrometers on high energy colliders. The interesting characteristics are zero field on beam axis, low fields at small angles, transverse field at large angles. Dimension range is 1 m to 5 m for clear bore and 2 m to 8 m for length; typical maximum field is 2.5 T. Superconducting magnets with cosine 2 {theta} structure, coils with one or two layers and iron yoke have been modeled. Use of two types of conductors have been investigated: Rutherford cable and aluminium stabilized composite. The paper describes the optimization procedure and gives diagrams of feasibility. Two alternative structures are mentioned: superferric and active shield magnets.

  7. Nb3Sn Quadrupole Magnets for the LHC IR

    SciTech Connect

    Sabbi, G.; Caspi, S.; Chiesa, L.; Coccoli, M.; Dietderich, D.r.; Ferracin, P.; Gourlay, S.A.; Hafalia, R.R.; Lietzke, A.F.; McInturff, A.D.; Scanlan, R.M.

    2001-08-01

    The development of insertion quadrupoles with 205 T/m gradient and 90 mm bore represents a promising strategy to achieve the ultimate luminosity goal of 2.5 x 10{sup 34} cm{sup -2}s{sup -1} at the Large Hadron Collider (LHC). At present, Nb{sub 3}Sn is the only practical conductor which can meet these requirements. Since Nb{sub 3}Sn is brittle, and considerably more strain sensitive than NbTi, the design concepts and fabrication techniques developed for NbTi magnets need to be modified appropriately. In addition, IR magnets must provide high field quality and operate reliably under severe radiation loads. The results of conceptual design studies addressing these issues are presented.

  8. Quadrupole collectivity of neutron-rich Neon isotopes

    E-print Network

    R. R. Rodriguez-Guzman; J. L. Egido; L. M. Robledo

    2003-02-04

    The angular momentum projected Generator Coordinate Method, with the quadrupole moment as collective coordinate and the Gogny force (D1S) as the effective interaction, is used to describe the properties of the ground state and low-lying excited states of the even-even Neon isotopes $^{20-34}$Ne, that is, from the stability valley up to the drip-line. It is found that the ground state of the N=20 nucleus $^{30}$Ne is deformed but to a lesser extent than the N=20 isotope of the Magnesium. In the calculations, the isotope $^{32}$Ne is at the drip-line in good agreement with other theoretical predictions. On the other hand, rather good agreement with experimental data for many observables is obtained.

  9. Levitated spinning graphene flakes in an electric quadrupole ion trap

    NASA Astrophysics Data System (ADS)

    Kane, B. E.

    2010-09-01

    A method is described for levitating micron-sized few-layer graphene flakes in an electric quadrupole ion trap. Starting from a liquid suspension containing graphene, charged flakes are injected into the trap using the electrospray ionization technique and are probed optically. At micro-torr pressures, torques from circularly polarized light cause the levitated particles to rotate at frequencies >1MHz , which can be inferred from modulation of light scattering off the rotating flake when an electric field resonant with the rotation rate is applied. Possible applications of these techniques will be presented, both to fundamental measurements of the mechanical and electronic properties of graphene and to new approaches to graphene crystal growth, modification, and manipulation.

  10. Quadrupole collectivity in neutron-rich Fe and Cr isotopes.

    PubMed

    Crawford, H L; Clark, R M; Fallon, P; Macchiavelli, A O; Baugher, T; Bazin, D; Beausang, C W; Berryman, J S; Bleuel, D L; Campbell, C M; Cromaz, M; de Angelis, G; Gade, A; Hughes, R O; Lee, I Y; Lenzi, S M; Nowacki, F; Paschalis, S; Petri, M; Poves, A; Ratkiewicz, A; Ross, T J; Sahin, E; Weisshaar, D; Wimmer, K; Winkler, R

    2013-06-14

    Intermediate-energy Coulomb excitation measurements are performed on the N ? 40 neutron-rich nuclei (66,68)Fe and (64)Cr. The reduced transition matrix elements providing a direct measure of the quadrupole collectivity B(E2;2(1)(+) ? 0(1)(+)) are determined for the first time in (68)Fe(42) and (64)Cr(40) and confirm a previous recoil distance method lifetime measurement in (66)Fe(40). The results are compared to state-of-the-art large-scale shell-model calculations within the full fpgd neutron orbital model space using the Lenzi-Nowacki-Poves-Sieja effective interaction and confirm the results of the calculations that show these nuclei are well deformed. PMID:25165918

  11. Alternative Mechanical Structure for LARP Nb3Sn Quadrupoles

    SciTech Connect

    Anerella, M.; Cozzolino, J.; Ambrosio, G.; Caspi, S.; Felice, H.; Kovach, P.; Lamm, M.; Sabbi, G.; Schmalzle, J.; Wanderer, P.

    2010-08-01

    An alternative structure for the 120 mm Nb{sub 3}Sn quadrupole magnet presently under development for use in the upgrade for LHC at CERN is presented. The goals of this structure are to build on the existing technology developed in LARP with the LQ and HQ series magnets and to further optimize the features required for operation in the accelerator. These features include mechanical alignment needed for field quality and provisions for cold mass cooling with 1.9 K helium in a helium pressure vessel. The structure will also optimize coil azimuthal and axial pre-load for high gradient operation, and will incorporate features intended to improve manufacturability, thereby improving reliability and reducing cost.

  12. Field Quality Study of the LARP Nb3Sn 3.7m-Long Quadrupole Models of LQ Series

    SciTech Connect

    AMbrosio, G.; Andreev, N.; Bossert, R.; Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Prebys, E.; Sylvester, C.; Tartaglia, M.; /Fermilab /LBL, Berkeley /Brookhaven

    2011-09-01

    After the successful test of the first long Nb{sub 3}Sn quadrupole magnet (LQS01), the US LHC Accelerator Research Program (LARP) has assembled and tested a new 3.7 m-long Nb{sub 3}Sn quadrupole (LQS02). This magnet has four new coils made of the same conductor as LQS01 coils, and it is using the same support structure. LQS02 was tested at the Fermilab Vertical Magnet Test Facility with the main goal to confirm that the long models can achieve field gradient above 200 T/m, LARP target for 90-mm aperture, as well as to measure the field quality. These long models lack some alignment features and it is important to study the field harmonics. Previous field quality measurements of LQS01 showed higher than expected differences between measured and calculated harmonics compared to the short models (TQS) assembled in a similar structure. These differences could be explained by the use of two different impregnation fixtures during coil fabrication. In this paper, we present a comparison of the field quality measurements between LQS01 and LQS02 as well as a comparison with the short TQS models. If the result supports the coil fabrication hypothesis, another LQS assembly with all coils fabricated in the same fixture will be produced for understanding the cause of the discrepancy between short and long models.

  13. Monte Carlo simulations of solute ordering in nematic liquid crystals: Shape anisotropy and quadrupole-quadrupole interactions as orienting mechanisms

    NASA Astrophysics Data System (ADS)

    Polson, James M.; Burnell, E. Elliott

    1997-04-01

    Monte Carlo computer simulations were used to investigate the effects of shape anisotropy and electrostatic interactions as mechanisms for orientational ordering of solutes in nematic liquid crystals. The simulation results were analyzed in terms of two theories of solute ordering which derive mean-field orientational potentials from the intermolecular pair potential. In the calculations, solute and solvent molecular shapes were approximated by hard ellipsoids. Most simulations also incorporated the interaction between point quadrupole moments placed at the centers of the ellipsoids. In the hard-core systems, orientational order parameters and distribution functions were calculated for a collection of different solutes under a variety of conditions. A theory due to Terzis and Photinos [Mol. Phys. 83, 847 (1994)] was found to underestimate the effect of shape anisotropy on orientational ordering drastically. The introduction of an effective solvent packing fraction was unable to improve the predictive power of the theory significantly. The quadrupolar systems were used to investigate a mean-field model for solute ordering which considers an interaction between the solute molecular quadrupole moment with an average electric-field gradient. The simulations indicate that the electric-field gradient sampled by the solute is highly dependent on the properties of the solute, contrary to some experimental evidence. Further, the effects of the intermolecular quadrupolar interactions on orientational ordering and the electric-field gradient were analyzed using a mean-field potential derived here and based on the theory due to Emsley, Palke, and Shilstone [Liq. Cryst. 9, 649 (1991)]. This model was found to provide a qualitatively correct but quantitatively imprecise prediction of orientational ordering.

  14. Optically detected chlorine quadrupole resonance investigation of the symmetry of the excited triplet state of tetrachlorobenzene and tetrachloropyrazine in single crystals of durene

    NASA Astrophysics Data System (ADS)

    von Borczyskowski, C.; Fallmer, E.

    1983-12-01

    Optically detected nuclear quadrupole resonance (ODNQR) transitions are reported for tetrachloropyrazine (TCP) and tetrachlorobenzene (TCB) in single crystals of durene in zero and external magnetic fields. The analysis of the fine structure results in D = 4.192 GHz and E = 0.591 GHz (TCP) compared to D = 4.555 GHz and E = 0.872 GHz (TCB). For the ??* triplet state of TCP a rotation of in-plane spin axes by 12° relative to the ground-state symmetry axes is observed.

  15. Matching an H(-) beam into a radio frequency quadrupole at Rutherford Appleton Laboratory.

    PubMed

    Gabor, C; Back, J J; Faircloth, D C; Lawrie, S R; Letchford, A P

    2014-02-01

    A major component of work being carried out to upgrade the ISIS spallation neutron source at Rutherford Appleton Laboratory (RAL) is the Front End Test Stand (FETS). FETS is aimed at improving the luminosity of the linac, and consists of a Penning ion source, Low Energy Beam Transport (LEBT), Radio Frequency Quadrupole (RFQ), and Medium Energy Beam Transport (MEBT). It may serve as a first part of the accelerator chain providing a 60 mA, 3 MeV H(-) beam up to a 10% duty cycle. The current output of the source and the transmission of the LEBT are reasonable, but there are issues with the alignment to provide a centred beam matched into the acceptance of the RFQ. Improvements have been made to the post acceleration to address this problem. Measurements with a collimated beam have been performed to understand the behaviour of the solenoids and steerer magnets. Comparing these results with simulations proved that, besides possible mechanical imperfections of the ion source and post acceleration assembly, agreement can only be achieved if the magnetic fields are distorted. PMID:24593479

  16. Development of a GC/Quadrupole-Orbitrap mass spectrometer, part II: new approaches for discovery metabolomics.

    PubMed

    Peterson, Amelia C; Balloon, Allison J; Westphall, Michael S; Coon, Joshua J

    2014-10-21

    Identification of unknown peaks in gas chromatography/mass spectrometry (GC/MS)-based discovery metabolomics is challenging, and remains necessary to permit discovery of novel or unexpected metabolites that may elucidate disease processes and/or further our understanding of how genotypes relate to phenotypes. Here, we introduce two new technologies and an analytical workflow that can facilitate the identification of unknown peaks. First, we report on a GC/Quadrupole-Orbitrap mass spectrometer that provides high mass accuracy, high resolution, and high sensitivity analyte detection. Second, with an "intelligent" data-dependent algorithm, termed molecular-ion directed acquisition (MIDA), we maximize the information content generated from unsupervised tandem MS (MS/MS) and selected ion monitoring (SIM) by directing the MS to target the ions of greatest information content, that is, the most-intact ionic species. We combine these technologies with (13)C- and (15)N-metabolic labeling, multiple derivatization and ionization types, and heuristic filtering of candidate elemental compositions to achieve (1) MS/MS spectra of nearly all intact ion species for structural elucidation, (2) knowledge of carbon and nitrogen atom content for every ion in MS and MS/MS spectra, (3) relative quantification between alternatively labeled samples, and (4) unambiguous annotation of elemental composition. PMID:25166283

  17. Electric quadrupole transition probabilities and line strengths of Ti{sup 11+}

    SciTech Connect

    Gökçe, Yasin, E-mail: ygokce58@gmail.com [Department of Physics, Faculty of Science, Karamanoglu Mehmetbey University, Karaman (Turkey); Çelik, Gültekin [Department of Physics, Faculty of Science, Selçuk University, Campus 42049 Konya (Turkey); Y?ld?z, Murat, E-mail: muraty70@gmail.com [Department of Physics, Faculty of Science, Karamanoglu Mehmetbey University, Karaman (Turkey)

    2014-07-15

    Electric quadrupole transition probabilities and line strengths have been calculated using the weakest bound electron potential model for sodium-like titanium, considering many transition arrays. We employed numerical Coulomb approximation and non-relativistic Hartree–Fock wavefunctions for the expectation values of radii in determination of parameters of the model. The necessary energy values have been taken from experimental data in the literature. The calculated electric quadrupole line strengths have been compared with available data in the literature and good agreement has been obtained. Moreover, some electric quadrupole transition probability and line strength values not existing in the literature for some highly excited levels have been obtained using this method.

  18. Electric quadrupole transitions in x-ray spectra: 3d transition-metal oxides

    NASA Astrophysics Data System (ADS)

    Dobrodey, N. V.; Luniakov, Yu. V.

    1995-02-01

    The intensities of the electric quadrupole transitions in the x-ray spectra of the 3d-transition-metal monoxide diatomic molecules were calculated using the discrete variational method of the local-density approximation. The quadrupole transition intensities have been found to be negligible for the left-hand-side 3d metal oxides. It was shown that the electric quadrupole transitions can appreciably contribute to the MK?5 emission spectra of the right-hand-side 3d metal oxides, along with the dipole transitions.

  19. Moments of the neutron charge form factor and the N->Delta quadrupole transition

    E-print Network

    P. Grabmayr; A. J. Buchmann

    2001-04-20

    Recent data allow a new parametrization of the neutron charge form factor G_En. A parameter-free quark model relation between G_En and the N->Delta quadrupole form factor is used to predict the latter from the G_En data. In particular, the neutron charge radius is related to N->Delta quadrupole moment, while the fourth moment of G_En connects to the N->Delta quadrupole transition radius. From the latter we derive an experimental value for the charge radius of the light constituent quarks. Finally, the C2/M1 ratio in pion electroproduction is predicted from the elastic neutron form factor data.

  20. TDPAC investigations of the 111 Cd quadrupole interaction in ternary chalcopyrite semiconductors

    Microsoft Academic Search

    S. Unterricker; T. Butz; W. Tröger

    1991-01-01

    The quadrupole interaction at room temperature of111Cd in CdSiP2, CdGeP2, and CdSnP2 is investigated by111mCd-TDPAC. The results are compared with those of former111In(111Cd) measurements. We observed axially symmetric quadrupole interactions with identical quadrupole coupling constants provided\\u000a that radiation damage was annealed. This proves that also In probes are positioned at Cd-sites (A-sites) in these ternary\\u000a compounds.

  1. Measurement of time dependent fields in high gradient superconducting quadrupoles for the Tevatron

    SciTech Connect

    Lamm, M.J.; Coulter, K.; Gourlay, S.; Jaffery, T.S.

    1990-10-01

    Magnetic field measurements have been performed on prototype and production magnets from two high gradient superconducting quadrupoles designs. One design is a double shell quadrupole with 36 strand Rutherford cable. The other design is a single shell quadrupole with 5 individually monolithic strands connected in series. These magnets have similar bore diameters and cable dimensions. However, there are significant differences between the two designs, as well as differences between prototype and production magnets within each design, with regard to Cu to superconductor ratio, filament diameter and filament spacing to strand diameter. The time dependence of fixed currents of the measured magnetic fields is discussed. 9 refs., 6 figs., 1 tab.

  2. Gravitational waves from inspiraling compact binaries: The quadrupole-moment term

    E-print Network

    Eric Poisson

    1997-09-12

    A rotating star's oblateness creates a deformation in the gravitational field outside the star, which is measured by the quadrupole-moment tensor. We consider the effect of the quadrupole moment on the orbital motion and rate of inspiral of a compact binary system, composed of neutron stars and/or black holes. We find that in the case of circular orbits, the quadrupole-monopole interaction affects the relation between orbital radius and angular velocity, and also the rate of inspiral, by a quantity of order (v/c)^4, where v is the orbital velocity and c the speed of light.

  3. Nb3Sn quadrupoles in the LHC IR Phase I upgrade

    SciTech Connect

    Zlobin, A.V.; Johnstone, J.A.; Kashikhin, V.V.; Mokhov, N.V.; Rakhno, I.L.; /Fermilab; de Maria, R.; Peggs, S.; Robert-Demolaize, G.; Wanderer, P.; /Brookhaven

    2008-06-01

    After a number of years of operation at nominal parameters, the LHC will be upgraded to a higher luminosity. This paper discusses the possibility of using a limited number of Nb{sub 3}Sn quadrupoles for hybrid optics layouts for the LHC Phase I luminosity upgrades with both NbTi and Nb{sub 3}Sn quadrupoles. Magnet parameters and issues related to using Nb{sub 3}Sn quadrupoles including aperture, gradient, magnetic length, field quality, operation margin, et cetera are discussed.

  4. Nb3Sn Quadrupoles in the LHC IR Phase I Upgrade

    SciTech Connect

    Zlobin,A.; Johnstone, J.; Kashikhin, V.; Mokhov, N.; Rakhno, I.; deMaria, R.; Peggs, S.; Robert-Demolaize, F.; Wanderer, P.

    2008-06-23

    After a number of years of operation at nominal parameters, the LHC will be upgraded for higher luminosity. This paper discusses the possibility of using a limited number of Nb{sub 3}Sn quadrupoles for hybrid optics layouts for the LHC Phase I luminosity upgrades with both NbTi and Nb{sub 3}Sn quadrupoles. Magnet parameters and issues related to using Nb{sub 3}Sn quadrupoles including aperture, gradient, magnetic length, field quality, operation margin, et cetera are discussed.

  5. Nuclear Speckles

    PubMed Central

    Spector, David L.; Lamond, Angus I.

    2011-01-01

    Nuclear speckles, also known as interchromatin granule clusters, are nuclear domains enriched in pre-mRNA splicing factors, located in the interchromatin regions of the nucleoplasm of mammalian cells. When observed by immunofluorescence microscopy, they usually appear as 20–50 irregularly shaped structures that vary in size. Speckles are dynamic structures, and their constituents can exchange continuously with the nucleoplasm and other nuclear locations, including active transcription sites. Studies on the composition, structure, and dynamics of speckles have provided an important paradigm for understanding the functional organization of the nucleus and the dynamics of the gene expression machinery. PMID:20926517

  6. Intrinsic quadrupole tensor in the geometric interpretation of the interacting boson approximation (IBA-1)

    SciTech Connect

    Marshalek, Eugene R. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2006-10-15

    For the first time, complete quantal expressions are provided for the intrinsic components of the quadrupole tensor in the geometric Holstein-Primakoff representation of the IBA-1. These expressions are valid throughout the Casten triangle.

  7. DEVELOPMENT AND TEST OF COLLARING METHODS FOR Nb{sub 3}SN QUADRUPOLE MAGNETS

    SciTech Connect

    Bossert, R.; Ambrosio, G.; Andreev, N.; Chlachidze, G.; Kashikhin, V. V.; Lamm, M.; Nobrega, F.; Novitski, I.; Tartaglia, M.; Yu, M.; Zlobin, A. V. [Fermi National Accelerator Laboratory, Batavia, Il. 60510 (United States)

    2010-04-09

    Fermilab is developing Nb{sub 3}Sn quadrupole magnets for the planned upgrade of interaction regions of the Large Hadron Collider (LHC). Two distinctly different approaches have been employed, one using quadrupole-symmetric and one using dipole-symmetric collar laminations. This paper describes the design features of both collar types, collaring techniques for brittle Nb{sub 3}Sn coils, and compares the advantages and disadvantages of the two approaches. Results of mechanical analysis for quadrupoles based on dipole-type and quadrupole-type collars are presented. Magnet construction issues and test results are reported. Test results include coil and component strain measurements during construction. Plans for the completion and test of the first dipole-symmetric assembly are described.

  8. Field quality measurements and abalysis of the LARP technology quadrupole models

    SciTech Connect

    Bossert, R.; Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.; Schlabach, P.; Tartaglia, M.; Tompkins, J.C.; Velev, G.V.; Zlobin, A.V.; Caspi, S.; /Fermilab /LBL, Berkeley

    2007-08-01

    One of the US-LHC accelerator research program goals is to develop and prove the design and technology of Nb{sub 3}Sn quadrupoles for an upgrade of the LHC Interaction Region (IR) inner triplets. Four 1-m long technology quadrupole models with a 90 mm bore and field gradient of 200 T/m based on similar coils and different mechanical structures have been developed. In this paper, we present the field quality measurements of the first several models performed at room temperature as well as at superfluid helium temperature in a wide field range. The measured field harmonics are compared to the calculated ones. The field quality of Nb{sub 3}Sn quadrupole models is compared with the NbTi quadrupoles recently produced at Fermilab for the first generation LHC IRs.

  9. Design and operation of a laminar-flow electrostatic-quadrupole-focused acceleration column

    SciTech Connect

    Maschke, A.W.

    1983-06-20

    This report deals with the design principles involved in the design of a laminar-flow electrostatic-quadrupole-focused acceleration column. In particular, attention will be paid to making the parameters suitable for incorporation into a DC MEQALAC design.

  10. MODAL ANALYSIS AND MEASUREMENT OF WATER COOLING INDUCED VIBRATIONS ON A CLIC MAIN BEAM QUADRUPOLE

    E-print Network

    Paris-Sud XI, Université de

    , the mechanical jitter of the CLIC main beam quadrupoles should be smaller than 1.5 nm integrated root mean square resin and the total mass of the coil is about 88 kg. Shims and insulating material are inserted between

  11. Kinetic equilibrium of space charge dominated beams in a misaligned quadrupole focusing channel

    NASA Astrophysics Data System (ADS)

    Goswami, A.; Sing Babu, P.; Pandit, V. S.

    2013-07-01

    The dynamics of intense beam propagation through the misaligned quadrupole focusing channel has been studied in a self-consistent manner using nonlinear Vlasov-Maxwell equations. The equations of motion of the beam centroid have been developed and found to be independent of any specific beam distribution. A Vlasov equilibrium distribution and beam envelope equations have been obtained, which provide us a theoretical tool to investigate the dynamics of intense beam propagating in a misaligned quadrupole focusing channel. It is shown that the displaced quadrupoles only cause the centroid of the beam to wander off axis. The beam envelope around the centroid obeys the familiar Kapchinskij-Vladimirskij envelope equation that is independent of the centroid motion. However, the rotation of the quadrupole about its optical axis affects the beam envelope and causes an increase in the projected emittances in the two transverse planes due to the inter-plane coupling.

  12. A modified quadrupole mass spectrometer with custom RF link rods driver for remote operation

    NASA Technical Reports Server (NTRS)

    Tashbar, P. W.; Nisen, D. B.; Moore, W. W., Jr.

    1973-01-01

    A commercial quadrupole residual gas analyzer system has been upgraded for operation at extended cable lengths. Operation inside a vacuum chamber for the standard quadrupole nude head is limited to approximately 2 m from its externally located rf/dc generator because of the detuning of the rf oscillator circuits by the coaxial cable reactance. The advance of long distance remote operation inside a vacuum chamber for distances of 45 and 60 m was made possible without altering the quadrupole's rf/dc generator circuit by employing an rf link to drive the quadrupole rods. Applications of the system have been accomplished for in situ space simulation thermal/vacuum testing of sophisticated payloads.

  13. High-performance MEMS square electrode quadrupole mass filters for chip-scale mass spectrometry

    E-print Network

    Cheung, Kerry

    We report exciting experimental data from a low-cost, high-performance square electrode quadrupole mass filter with integrated ion optics intended for chips-cale mass spectrometry. The device showed a mass range of 650 amu ...

  14. Rotational and magnetic shunt permanent magnet quadrupoles with variable magnetic strength

    SciTech Connect

    Vladimir Kashikhin et al.

    2002-03-28

    Next Linear Collider (NLC) and Very Large Hadron Collider (VLHC) projects suppose to use permanent magnets as bending, focusing and correcting elements. Prototypes of two permanent magnet quadrupoles with variable strength were built and successfully tested in Fermilab. Quadrupoles have 12.7 mm aperture diameter, 100 T/m gradient with an adjustment range of 0 to -20%. Special designs provide high precision magnetic center stability during strength change. SmCo5 permanent magnet bricks were used in these prototypes. Rotational quadrupole consists of four sections. Two central sections are rotated in counter directions to adjust the strength. Magnetic shunt quadrupole design provides variable shunting of the magnetic flux. The numerical simulation, designs, measuring results are described.

  15. Field Quality Measurements and Analysis of the LARP Technology Quadrupole Models

    SciTech Connect

    Chlachidze, G.; DiMarco, J.; Kashikhin, V.V.; Lamm, M.; Schlabach, P.; Tartaglia, M.; Tompkins, J.C.; Velev, G.V.; Zlobin, A.V.; Caspi, S.; Ferracin, P.; Sabbi, G.I.; Bossert, R.

    2008-06-01

    One of the US-LHC accelerator research program goals is to develop and prove the design and technology of Nb{sub 3}Sn quadrupoles for an upgrade of the LHC Interaction Region (IR) inner triplets. Four 1-m long technology quadrupole models with a 90 mm bore and field gradient of 200 T/m based on similar coils and different mechanical structures have been developed. In this paper, we present the field quality measurements of the first several models performed at room temperature as well as at superfluid helium temperature in a wide field range. The measured field harmonics are compared to the calculated ones. The field quality of Nb{sub 3}Sn quadrupole models is compared with the NbTi quadrupoles recently produced at Fermilab for the first generation LHC IRs.

  16. Set Up and Test Results for a Vibrating Wire System for Quadrupole Fiducialization

    SciTech Connect

    Levashov, Michael Y.

    2010-12-01

    Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of a quadrupole. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing it. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet center (step 1), finding the wire with position detectors (step 2), and finding the quadrupole tooling ball positions relative to the position detector tooling balls (step 3). The following break up of error was suggested for the fiducialization steps: 10{micro}m for step 1 (finding the center), 20{micro}m for step 2 (finding the wire), and 10{micro}m for step 3 (tooling ball measurements). The purpose of this study is to investigate whether the vibrating wire system meets the requirements for LCLS. In particular, if it can reliably fiducialize a quadrupole magnetic center to within 25{micro}m in both vertical and horizontal directions. The behavior of individual system components is compared to the expected performance. A vibrating wire system was constructed to fiducialize the quadrupoles between undulator segments in the LCLS. This note studies the ability of the system to fulfill the fiducialization requirements.

  17. Set Up and Test Results for a Vibrating Wire System for Quadrupole Fiducialization

    SciTech Connect

    Not Available

    2010-11-29

    Quadrupoles will be placed between the undulator segments in LCLS to keep the electron beam focused as it passes through. The quadrupoles will be assembled with their respective undulator segments prior to being placed into the tunnel. Beam alignment will be used to center the quadrupoles, along with the corresponding undulators, on the beam. If there is any displacement between the undulator and the quadrupole axes in the assemblies, the beam will deviate from the undulator axis. If it deviates by more than 80{micro}m in vertical or 140{micro}m in horizontal directions, the undulator will not perform as required by LCLS. This error is divided between three sources: undulator axis fiducialization, quadrupole magnetic axis fiducialization, and assembly of the two parts. In particular, it was calculated that the quadrupole needs to be fiducialized to within 25{micro}m in both vertical and horizontal directions. A previous study suggested using a vibrating wire system for finding the magnetic axis of a quadrupole. The study showed that the method has high sensitivity (up to 1{micro}m) and laid out guidelines for constructing it. There are 3 steps in fiducializing the quadrupole with the vibrating wire system. They are positioning the wire at the magnet center (step 1), finding the wire with position detectors (step 2), and finding the quadrupole tooling ball positions relative to the position detector tooling balls (step 3). The following break up of error was suggested for the fiducialization steps: 10{micro}m for step 1 (finding the center), 20{micro}m for step 2 (finding the wire), and 10{micro}m for step 3 (tooling ball measurements). The purpose of this study is to investigate whether the vibrating wire system meets the requirements for LCLS. In particular, if it can reliably fiducialize a quadrupole magnetic center to within 25{micro}m in both vertical and horizontal directions. The behavior of individual system components is compared to the expected performance. A vibrating wire system was constructed to fiducialize the quadrupoles between undulator segments in the LCLS. This note studies the ability of the system to fulfill the fiducialization requirements.

  18. Measurement of density-sensitive electric quadrupole transitions in neonlike laser-produced plasmas

    SciTech Connect

    Young, B.K.F.; Osterheld, A.L.; Walling, R.S.; Goldstein, W.H.; Phillips, T.W.; Stewart, R.E.; Charatis, G.; Busch, G.E.

    1989-03-13

    We report on the measurement of density-sensitive electric quadrupole transitions in neonlike molybdenum and silver laser-produced plasmas. These observations are unique in that they represent data which are simultaneously space and time resolved. The electron densities were determined using holographic interferometry. We test the predicted density sensitivity of the electric quadrupole transitions and find excellent agreement with calculations using a detailed, steady-state, collisional-radiative model of the neonlike charge state.

  19. PERFORMANCE OF NB{sub 3}SN QUADRUPOLE MAGNETS UNDER LOCALIZED THERMAL LOAD

    SciTech Connect

    Kashikhin, V. V.; Bossert, R.; Chlachidze, G.; Lamm, M.; Mokhov, N. V.; Novitski, I.; Zlobin, A. V. [Fermi National Accelerator Laboratory, Batavia, IL, 60510 (United States)

    2010-04-09

    This paper describes the results of design and analyses performed on 120-mm Nb{sub 3}Sn and NbTi quadrupole magnets with parameters relevant for the LHC IR upgrade. A realistic radiation heat load is evaluated in a wide luminosity range and translated into the magnet quench performance. The simulation results are supported by thermal measurements on a 90-mm Nb{sub 3}Sn quadrupole coil.

  20. Global investigation of the fine structure of the isoscalar giant quadrupole resonance

    Microsoft Academic Search

    A. Shevchenko; O. Burda; Y. Kalmykov; P. von Neumann-Cosel; V. Yu. Ponomarev; A. Richter; J. Wambach; J. Carter; E. Sideras-Haddad; G. R. J. Cooper; R. W. Fearick; S. V. Foertsch; J. J. Lawrie; R. Neveling; F. D. Smit; H. Fujita; Y. Fujita; D. Lacroix

    2009-01-01

    Fine structure in the region of the isoscalar giant quadrupole resonance (ISGQR) in Ni, Y, °Zr, ¹²°Sn, ¹Er, and ²°Pb has been observed in high-energy-resolution (E35-50 keV) inelastic proton scattering measurements at E=200 MeV at iThemba LABS. Calculations of the corresponding quadrupole excitation strength functions performed within models based on the random-phase approximation (RPA) reveal similar fine structure when the

  1. Design report of the QTG quadrupoles for the CERN CNGS line

    E-print Network

    Zickler, T

    2000-01-01

    This report presents the actual QTG design. The quadrupole magnets are part of the "CERN Neutrino to Gran Sasso" transfer line TT40. The design is optimized for a nominal beam energy of 400 GeV. The quadrupoles are resistive iron-dominated magnets with a gradient of 40 T/m and an inscribed radius of 22.5 mm. The 2200 mm long yokes will be built form low carbon steel laminations stacked between non-laminated end plates.

  2. Hybridized quadrupole-dipole exciton effects in a Cu2O -organic heterostructure

    Microsoft Academic Search

    Oleksiy Roslyak; Joseph L. Birman

    2007-01-01

    In the present work, we discuss resonant hybridization of the 1S quadrupole Wannier-Mott exciton (WE) in a Cu2O quantum well with the Frenkel dipole exciton in an adjacent layer of organic DCM2:CA:PA. The coupling between excitons is due to interaction between the gradient of electric field induced by the DCM2 Frenkel exciton (FE) and the quadrupole moment of the 1S

  3. Quadrupole source in prediction of the noise of rotating blades - A new source description

    Microsoft Academic Search

    F. Farassat

    1987-01-01

    The aim of this paper is to perform a theoretical study of the quadrupole term of the Ffowcs Williams-Hawkings (FW-H) equation to obtain practical results for applications to rotating blades. The quadrupole term of the FW-H equation is algebraically manipulated into volume, surface and line sources using generalized function theory and differential geometry. The volume source is of the type

  4. Adjustable Permanent Quadrupoles Using Rotating Magnet Material Rods for the Next Linear Collider

    Microsoft Academic Search

    James T Volk

    2001-01-01

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 132 Tesla, with a maximum gradient of 135 Tesla per meter, an adjustment range of +0-20% and effective lengths from 324 mm to 972 mm. The magnetic

  5. Permanent Magnet Skew Quadrupoles for the Low Emittance LER Lattice of PEP-II

    SciTech Connect

    Decker, F.-J.; Anderson, S.; Kharakh, D.; Sullivan, M.; /SLAC

    2011-07-05

    The vertical emittance of the low energy ring (LER) in the PEP-II B-Factory was reduced by using skew quadrupoles consisting of permanent magnet material. The advantages over electric quadrupoles or rotating existing normal quadrupoles are discussed. To assure a high field quality, a Biot-Savart calculation was used to cancel the natural 12-pole component by using different size poles over a few layers. A magnetic measurement confirmed the high quality of the magnets. After installation and adjusting the original electric 12 skew and 16 normal quadrupoles the emittance contribution from the region close to the interaction point, which was the biggest part in the original design, was considerably reduced. To strengthen the vertical behavior of the LER beam, a low emittance lattice was developed. It lowered the original vertical design emittance from 0.54 nm-rad to 0.034 nm-rad. In order to achieve this, additional skew quadrupoles were required to bring the coupling correction out of the arcs and closer to the detector solenoid in the straight (Fig. 1). It is important, together with low vertical dispersion, that the low vertical emittance is not coupled into the horizontal, which is what we get if the coupling correction continues into the arcs. Further details of the lattice work is described in another paper; here we concentrate on the development of the permanent skew (PSK) quadrupole solution. Besides the permanent magnets there are two other possibilities, using electric magnets or rotating normal quadrupoles. Electric magnets would have required much more additional equipment like magnets stands, power supply, and new vacuum chamber sections. Rotating existing quadrupoles was also not feasible since they are mostly mounted together with a bending magnet on the same support girder.

  6. Compact IR Quadrupoles for Linear Colliders Based on Rutherford-type Cable

    SciTech Connect

    Lopes, M.L.; Kashikhin, V.S.; Kashikhin, V.V.; Zlobin, A.V.; /Fermilab

    2008-08-01

    The upcoming and disrupted beams in the interaction region (IR) of a linear collider are focused by doublets consisting of two small-aperture superconducting quadrupoles. These magnets need an effective compact magnetic shielding to minimize magnetic coupling between the two channels and sufficient temperature margin to withstand radiation-induced heat depositions in the coil. This paper presents conceptual designs of IR quadrupoles for linear colliders based on NbTi and Nb{sub 3}Sn Rutherford-type cables.

  7. Performance of Nb3Sn quadrupole magnets under localized thermal load

    SciTech Connect

    Kashikhin, V.V.; Bossert, r.; Chlachidze, G.; Lamm, M.; Mokhov, N.V.; Novitski, I.; Zlobin, A.V.; /Fermilab

    2009-06-01

    This paper describes the results of design and analyses performed on 120-mm Nb{sub 3}Sn and NbTi quadrupole magnets with parameters relevant for the LHC IR upgrade. A realistic radiation heat load is evaluated in a wide luminosity range and translated into the magnet quench performance. The simulation results are supported by thermal measurements on a 90-mm Nb{sub 3}Sn quadrupole coil.

  8. Bose-Einstein condensation in a quadrupole-Ioffe-configuration trap

    Microsoft Academic Search

    Tilman Esslinger; Immanuel Bloch; Theodor W. Hänsch

    1998-01-01

    We demonstrate Bose-Einstein condensation of rubidium atoms in a simple low-power magnetic trap. This trap combines the quadrupole with the Ioffe configuration (QUIC trap) and consists of just three coils. Magneto-optically trapped 87Rb atoms are first loaded into the linear trapping potential of a magnetic quadrupole, which is then converted into the parabolic geometry of an Ioffe trap. During this

  9. Errors and optics study of a permanent magnet quadrupole system

    NASA Astrophysics Data System (ADS)

    Schillaci, F.; Maggiore, M.; Rifuggiato, D.; Cirrone, G. A. P.; Cuttone, G.; Giove, D.

    2015-05-01

    Laser-based accelerators are gaining interest in recent years as an alternative to conventional machines [1]. Nowadays, energy and angular spread of the laser-driven beams are the main issues in application and different solutions for dedicated beam-transport lines have been proposed [2,3]. In this context a system of permanent magnet quadrupoles (PMQs) is going to be realized by INFN [2] researchers, in collaboration with SIGMAPHI [3] company in France, to be used as a collection and pre-selection system for laser driven proton beams. The definition of well specified characteristics, both in terms of performances and field quality, of the magnetic lenses is crucial for the system realization, for an accurate study of the beam dynamics and the proper matching with a magnetic selection system already realized [6,7]. Hence, different series of simulations have been used for studying the PMQs harmonic contents and stating the mechanical and magnetic tolerances in order to have reasonable good beam quality downstream the system. In this paper is reported the method used for the analysis of the PMQs errors and its validation. Also a preliminary optics characterization is presented in which are compared the effects of an ideal PMQs system with a perturbed system on a monochromatic proton beams.

  10. Fast quadrupole pulsed power supply in the AGS

    SciTech Connect

    Nawrocky, R.J.; Halama, H.J.; Lambiase, R.F.; Montemurro, P.A.

    1984-01-01

    As part of the Polarized Proton Project at the AGS, a pulsed power supply system has been developed to energize a set of twelve fast quadrupoles which are symmetrically distributed around the 1/2-mile circumference of the machine. During a typical acceleration cycle, which is normally repeated every 2.4 s, these magnets are energized with bursts of triangular current pulses. The rise-time of each pulse is less than 2 ..mu..s and the width at the base varies from 1 to 3.5 ms depending on the pulse. Within a burst, pulses alternate in polarity and vary in amplitude from 160 A to 2700 A peak. Pulse separation is on the order of 40 ms. Due to the distributed nature of the load and high di/dt, each magnet is powered by a separate modulator. Magnets are driven via coaxial pulse transmission cables up to 200 ft long. In the modulators, the high power pulses are switched with thyratron/ignitron switch pairs. All modulators are charged in parallel with a common system of programmable high voltage power supplies. The overall system is controlled with a distributed network of microcomputers. This paper describes the development, construction and initial performance of the pulsed power supply system.

  11. Hybrid permanent magnet quadrupoles for the Recycler Ring at Fermilab

    SciTech Connect

    Brown, B.C.; Pruss, S.M.; Foster, G.W.; Glass, H.D.; Harding, D.J.; Jackson, G.R.; May, M.R.; Nicol, T.H.; Ostiguy, J.-F.; Schlabach, R.; Volk, J.T.

    1997-10-01

    Hybrid Permanent Magnet Quadrupoles are used in several applications for the Fermilab Recycler Ring and associated beam transfer lines. Most of these magnets use a 0.6096 m long iron shell and provide integrated gradients up to 1.4 T-m/m with an iron pole tip radius of 41.6 mm. A 58.4 mm pole radius design is also required. Bricks of 25. 4 mm thick strontium ferrite supply the flux to the back of the pole to produce the desired gradients (0.6 to 2.75 T/m). For temperature compensation, Ni-Fe alloy strips are interspersed between ferrite bricks to subtract flux in a temperature dependent fashion. Adjustments of the permeance of each pole using iron between the pole and the flux return shell permits the matching of pole potentials. Magnetic potentials of the poles are adjusted to the desired value to achieve the prescribed strength and field uniformity based on rotating coil harmonic measurements. Procurement, fabrication, pole potential adjustment, and measured fields will be reported.

  12. A toroidal trap for the cold $^{87}Rb$ atoms using a rf-dressed quadrupole trap

    E-print Network

    Chakraborty, A; Ram, S P; Tiwari, S K; Rawat, H S

    2015-01-01

    We demonstrate the trapping of cold $^{87}Rb$ atoms in a toroidal geometry using a rf-dressed quadrupole magnetic trap formed by superposing a strong radio frequency (rf) field on a quadrupole trap. This rf-dressed quadrupole trap has minimum of the potential away from the quadrupole trap centre on a circular path which facilitates the trapping in the toroidal geometry. In the experiments, the laser cooled atoms were first trapped in the quadrupole trap, then cooled evaporatively using a weak rf-field, and finally trapped in the rf-dressed quadrupole trap. The radius of the toroid could be varied by varying the frequency of the dressing rf-field. It has also been demonstrated that a single rf source and an antenna can be used for the rf-evaporative cooling as well as for rf-dressing of atoms. The atoms trapped in the toroidal trap may have applications in realization of an atom gyroscope as well as in studying the quantum gases in low dimensions.

  13. (U) Nuclear Data

    SciTech Connect

    White, Morgan C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-23

    Nuclear data comes from a variety of sources and in many flavors. Understanding where the data you use comes from and what flavor it is can be essential to understand and interpret your results. This talk will discuss the nuclear data pipeline with particular emphasis on providing links to additional resources that can be used to explore the issues you will encounter.

  14. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are…

  15. The plant nuclear envelope

    Microsoft Academic Search

    Annkatrin Rose; Shalaka Patel; Iris Meier

    2004-01-01

    This review summarizes our present knowledge about the composition and function of the plant nuclear envelope. Compared with animals or yeast, our molecular understanding of the nuclear envelope in higher plants is in its infancy. However, fundamental differences in the structure and function of the plant and animal nuclear envelope have already been found. Here, we compare and contrast these

  16. Stochastic nuclear dynamics

    SciTech Connect

    Bolotin, Y.L.; Gonchar, V.Y.; Inopin, E.V.; Levenko, V.V.; Tarasov, V.N.; Chekanov, N.A. (Khar'kov Physicotechnical Institute, Ukrainian Academy of Sciences, Khar'kov (UA))

    1989-07-01

    The transition from regular to random motion is studied for collective nuclear processes with large amplitude. The connection between the features of the dynamics and the geometry of the potential-energy surface is studied. Some two-dimensional dynamical systems, including quadrupole surface vibrations of nuclei and induced nuclear fission, are studied in detail. Some quantum manifestations of classical stochasticity are investigated, in particular the connection between the statistical properties of the quantum energy spectra and the nature of the motion---regular or random---in the classical limit. For potentials with a localized region of negative Gaussian curvature there is found to be a triple transition: regularity--chaos--regularity, and its influence on the statistical properties of the spectrum is investigated.

  17. Fabrication and Test of 90-mm Nb3Sn Quadrupole Model Based on Dipole-type Collar

    SciTech Connect

    Bossert, R.; Andreev, N.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; Tartaglia, M.; Velev, G.; Zlobin, A.V.; /Fermilab

    2010-07-29

    A series of 90-mm TQC quadrupole models with a collar-based mechanical structure has been fabricated and tested within the framework of the US-LHC Accelerator Research Program (LARP) using quadrupole-symmetric stainless steel collar laminations. This paper describes the design features, construction and test of TQC02Eb, the first TQC made with dipole-type collar and collaring techniques. Magnet test includes quench performance and field quality measurements at 4.5 and 1.9 K. Results of model performance for TQC quadrupoles based on dipole-type and quadrupole-type collars are compared and discussed.

  18. Subfemtotesla radio-frequency atomic magnetometer for detection of nuclear quadrupole resonance

    E-print Network

    Romalis, Mike

    Hz 14 N NQR frequency of ammonium nitrate. A potential application of the magnetometer is detection-to-noise ratio SNR below a few megahertz. The NQR signal from 22 g of powdered ammonium nitrate located 2 cm away from the sensor is detected with a SNR of 9 in a 4.4-s-long multiple echo sequence, which represents

  19. Hyperfine and Nuclear Quadrupole Interactions in Copper-Doped TiO2

    Microsoft Academic Search

    T. C. Ensign; Te-Tse Chang; A. H. Kahn

    1969-01-01

    Single crystals of TiO2:Cu2+ have been investigated at 20 K using the technique of electron paramagnetic resonance. The major features of the EPR spectra can be attributed to divalent copper (3d9) in substitutional (Ti4+) sites. Information has been gained about both isotopes of copper and about the interactions which concern this ion. For the substitutional site, the spin-Hamiltonian parameters in

  20. Off-resonance effects and selectivity profiles in pulsed nitrogen-14 nuclear quadrupole resonance.

    PubMed

    Guendouz, L; Robert, A; Retournard, A; Leclerc, S; Aissani, S; Canet, D

    2012-01-01

    In order to alleviate base-line distortions in nitrogen-14 NQR spectra originating from pulse breakthrough, low power radio-frequency (rf) pulses were applied. It is recalled that the required power is four times lower than that for an equivalent NMR experiment. This is easily explained by the fact that, in NMR, half the amplitude of the rf field is active. Moreover, the selectivity profile (i.e. the peak amplitude as a function of the difference between the carrier frequency and the resonance frequency) exhibits a shape which is, in most cases, more favorable in NQR than in NMR. An appropriate theory has been developed for explaining these experimental observations. It is concluded that low power NQR is perfectly feasible and should even be recommended for most applications, provided that the line-width of the NQR signal is not too large. PMID:23063174

  1. Digital Methods of Detecting a Low-Frequency Nuclear Quadrupole Resonance

    Microsoft Academic Search

    É. O. Azizov; V. S. Grechishkin; A. V. Gaevskii; V. V. Korostelev

    2003-01-01

    absorption signal [2] was used. In 1985, a new device operating at a frequency of 5192 kHz (RDX) [3] was developed to detect TS-2.5, TS-6, and M-14 mines (its operation frequency for tetryl detection was 5290 kHz). In the process of mine fabrication, molten tetryl solidifies directly in the mine body and represents a solid solution; therefore, the N 14

  2. Nuclear Quenching in Gaseous Argon

    Microsoft Academic Search

    Kareem Kazkaz; Adam Bernstein; Michael Foxe; Christian Hagmann; Igor Jovanovic; Wolfgang Stoeffl; Celeste Winant

    2008-01-01

    In many media and with varying degrees of efficiency, nuclear recoils can induce ionization and\\/or scintillation. These nuclear recoil signatures can be used in dark matter searches and neutrino physics experiments, and to detect neutrons. To understand the behavior of the ionization process induced by nuclear recoils, nuclear quenching factors must be measured at various energies to properly reconstruct the

  3. Design and fabrication of the prototype superconducting quadrupole for the CERN LHC project

    SciTech Connect

    Baze, J.M.; Cacaut, D.; Jacquemin, J.P.; Lyraud, C.; Michez, C.; Pabot, Y.; Perot, J.; Rifflet, J.M.; Toussaint, J.C.; Vedrine, P. (CEA/Saclay/DSM/DPhPE/STIPE, 91191 Gif-sur-Yvette (FR))

    1992-01-01

    Within the framework of the LHC R and D program, CERN and CEA/Saclay have established a collaboration to carry out, amongst others, the design, building and testing of a superconducting LHC prototype quadrupole at the Saclay laboratory. The cold mass of this quadrupole is presently under construction at Saclay. The quadrupole design features a twin aperture configuration, a gradient design features a twin aperture configuration, a gradient of 250T/m, a length of 3m and a free coil aperture of 56mm. European industries participate in this project by delivering components and fabrication the tooling according to specifications prepared by Saclay. This paper gives details of the magnet design and construction. Coil winding will start in summer 1991 and the first prototype should be assembled and ready for testing by mid 1992.

  4. Magnetic field in the end region of the SSC quadrupole magnet

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J.

    1991-06-01

    Recent advances in methods of computing magnetic fields have made it possible to study the field in the end region of the SS quadrupole magnet in detail. The placement of conductor in the straight section, away from the ends, was designed to produce a practically pure quadrupole field in the two-dimensional sense. The ends of the coils were designed to produce a practically pure quadrupole field in the integral sense using a method that ignores the presence of the iron yoke. Subsequently, the effect of presence of the yoke on the field was analyzed. The paper presents the end configuration together with the computed integrated multipole components, local multipole components, and local field components. A comparison with measurements is included. 5 refs., 5 figs., 1 tab.

  5. Magnetic field in the end region of the SSC quadrupole magnet

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J. (Lawrence Berkeley Lab., CA (United States))

    1992-01-01

    Recent advances in methods of computing magnetic fields have made it possible to study the field in the end region of the SSC quadrupole magnet in detail. The placement of conductor in the straight section, away from the ends, was designed to produce a practically pure quadrupole field in the two-dimensional sense. The ends of the coils were designed to produce a practically pure quadrupole field in the integral sense using a method that ignores the presence of the iron yoke. Subsequently, the effect of the presence of the yoke on the field was analyzed. The paper presents the end configuration together with the computer integrated multipole components, local multipole components, and local field components. A comparison with measurements is included.

  6. Magnetic and Mechanical Analysis of the HQ Model Quadrupole Designs for LARP

    SciTech Connect

    Felice, Helene; Caspi, Shlomo; Ferracin, Paolo; Kashikhin, Vadim; Novitski, Igor; Sabbi, GianLuca; Zlobin, Alexander

    2008-06-01

    Insertion quadrupoles with large bore and high gradient are required to upgrade the luminosity of the Large Hadron Collider (LHC). The US LHC Accelerator Research Program is developing Nb{sub 3}Sn technology for the upgrade. This effort includes a series of 1 m long Technology Quadrupoles (TQ), to demonstrate the reproducibility at moderate field, and High-gradient Quadrupoles (HQ) to explore the magnet performance limits in terms of peak fields, forces and stresses. The HQ models are expected to achieve peak fields of 15 T or higher. A coil aperture of 90 mm, corresponding to gradients above 300 T/m, was chosen as the baseline. Peak stresses above 150 MPa are expected. Progress on the magnetic and mechanical design of the HQ models will be reported.

  7. Design and Field Measurements of Printed-Circuit Quadrupoles and Dipoles

    SciTech Connect

    Zhang, W.W.; Bernal, S.; Li, H.; Godlove, T.; Kishek, R.A.; O'Shea, P.G.; Reiser, M.; Yun, V.; /Maryland U., IPR; Venturini, M.; /SLAC

    2011-11-08

    Air-core printed-circuit (PC) quadrupoles and dipoles have been developed for the University of Maryland electron ring, currently under construction. The quadrupoles and dipoles are characterized by very small magnetic fields (about 15 G at the aperture edge) and small aspect ratios (length/diameter < 1). We review the theory behind the design of the PC lenses and bending elements, and present general expressions for estimating the values of integrated field and integrated field gradient as functions of design parameters. The new quadrupole magnet represents an improvement over an earlier version which was based on an empirical approach. Further, we summarize the results of multipole content of the magnet fields as measured with a rotating coil apparatus of special construction. The results are compared with calculations with an iron-free magnetics code and are related to different types of errors in the manufacture and assembly of the PC magnets.

  8. SU(6) quadrupole phonon model for even and odd nuclei and the SU(3) limit

    NASA Astrophysics Data System (ADS)

    Paar, V.; Brant, S.; Canto, L. F.; Leander, G.; Vouk, M.

    1982-04-01

    Analogous to the equivalence between the SU(6) quadrupole-phonon model (TQM) and the interacting boson model (IBM), the equivalence is pointed out for odd systems between the SU(6) particle quadrupole-phonon coupling model (PTQM) and the interacting boson-fermion model (IBFM). PTQM is formulated starting from the Dyson representation for the odd system. Different aspects of the SU(3) limit of TQM and PTQM are studied; the quadrupole-phonon block structure of rotational bands in even and odd nuclei and analytic expressions based on the coherent state; signature effects generated in PTQM; electromagnetic properties and correction factors for PTQM; overlaps of the PTQM analogs of Nilsson states with Coriolis-coupled Nilsson states and the relation to the rotational model representation.

  9. Surface-enhanced pair transfer in quadrupole states of neutron-rich Sn isotopes

    E-print Network

    Masayuki Matsuo; Yasuyoshi Serizawa

    2010-07-10

    We investigate the neutron pair transfer modes associated with the low-lying quadrupole states in neutron-rich Sn isotopes by means of the quasiparticle random phase approximation based on the Skyrme-Hartree-Fock-Bogoliubov mean field model. The transition strength of the quadrupole pair-addition mode feeding the $2_1^+$ state is enhanced in the Sn isotopes with $A \\geq 132$. The transition density of the pair-addition mode has a large spatial extension in the exterior of nucleus, reaching far to $r\\sim 12-13$ fm. The quadrupole pair-addition mode reflects sensitively a possible increase of the effective pairing interaction strength in the surface and exterior regions of neutron-rich nuclei.

  10. Antimagnetic rotation and sudden change of electric quadrupole transition strength in 143Eu

    E-print Network

    S. Rajbanshi; S. Roy; Somnath Nag; Abhijit Bisoi; S. Saha; J. Sethi; T. Trivedi; T. Bhattacharjee; S. Bhattacharyya; S. Chattopadhyay; G. Gangopadhyay; G. Mukherjee; R. Palit; R. Raut; M. Saha Sarkar; A. K. Singh; A. Goswami

    2015-05-22

    Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method as well as parity of the states in the sequence has been firmly identified from polarization measurement using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B(E2) with spin, along with increasing J (2) /B(E2) values before band crossing, conclusively establish the origin of these states as arising out of antimagnetic rotation. The abrupt increase in the B(E2) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may indicates the crossing of different shears configurations resulting in re-opening of shears structure. The results are well reproduced by numerical calculation within the framework of semi-classical geometric model.

  11. Development of a GC/Quadrupole-Orbitrap mass spectrometer, part I: design and characterization.

    PubMed

    Peterson, Amelia C; Hauschild, Jan-Peter; Quarmby, Scott T; Krumwiede, Dirk; Lange, Oliver; Lemke, Rachelle A S; Grosse-Coosmann, Florian; Horning, Stevan; Donohue, Timothy J; Westphall, Michael S; Coon, Joshua J; Griep-Raming, Jens

    2014-10-21

    Identification of unknown compounds is of critical importance in GC/MS applications (metabolomics, environmental toxin identification, sports doping, petroleomics, and biofuel analysis, among many others) and remains a technological challenge. Derivation of elemental composition is the first step to determining the identity of an unknown compound by MS, for which high accuracy mass and isotopomer distribution measurements are critical. Here, we report on the development of a dedicated, applications-grade GC/MS employing an Orbitrap mass analyzer, the GC/Quadrupole-Orbitrap. Built from the basis of the benchtop Orbitrap LC/MS, the GC/Quadrupole-Orbitrap maintains the performance characteristics of the Orbitrap, enables quadrupole-based isolation for sensitive analyte detection, and includes numerous analysis modalities to facilitate structural elucidation. We detail the design and construction of the instrument, discuss its key figures-of-merit, and demonstrate its performance for the characterization of unknown compounds and environmental toxins. PMID:25208235

  12. Electric Quadrupole Shift Cancellation in Single-Ion Optical Frequency Standards

    SciTech Connect

    Dube, P.; Madej, A.A.; Bernard, J.E.; Marmet, L.; Boulanger, J.-S.; Cundy, S. [Institute for National Measurement Standards, National Research Council, Ottawa, K1A 0R6 (Canada)

    2005-07-15

    The electric quadrupole shift is presently the most significant source of uncertainty on the systematic shifts for several single-ion optical frequency standards. We present a simple method for canceling this shift based on measurements of the Zeeman spectrum of the clock transition. This method is easy to implement and yields very high cancellation levels. A fractional uncertainty of 5x10{sup -18} for the canceled quadrupole shift is estimated for a measurement of the absolute frequency of the 5s {sup 2}S{sub 1/2}-4d {sup 2}D{sub 5/2} clock transition of {sup 88}Sr{sup +}.

  13. Search for Quadrupole Strength in the Electro-excitation of the Delta(1232)

    E-print Network

    C. Mertz; C. Vellidis; R. Alarcon; D. H. Barkhuff; A. M. Bernstein; W. Bertozzi; V. Burkert; J. Chen; J. R. Comfort; G. Dodson; S. Dolfini; K. Dow; M. Farkhondeh; J. M. Finn; S. Gilad; R. W. Gothe; X. Jiang; K. Joo; N. I. Kaloskamis; A. Karabarbounis; J. J. Kelly; S. Kowalski; C. Kunz; R. W. Lourie; J. I. McIntyre; B. D. Milbrath; R. Miskimen; J. H. Mitchell; C. N. Papanicolas; C. F. Perdrisat; A. J. Sarty; J. Shaw; S. -B. Soong; D. Tieger; C. Tschalaer; W. Turchinetz; P. E. Ulmer; S. Van Verst; G. A. Warren; L. B. Weinstein; S. Williamson; R. J. Woo; A. Young

    2000-12-06

    High-precision H(e,e'p)pi0 measurements at Q2=0.126 (GeV/c)2 are reported, which allow the determination of quadrupole amplitudes in the gamma* N->Delta transition; they simultaneously test the reliability of electroproduction models. The derived quadrupole-to-dipole amplitude ratios, Rsm=(-6.5 +- 0.2{stat+sys} +- 2.5{mod}) % and Rem=(-2.1 +- 0.2{stat+sys} +- 2.0{mod}) %, are dominated by model error. Previous Rsm and Rem results should be reconsidered after the model uncertainties associated with the method of their extraction are taken into account.

  14. Global investigation of the fine structure of the isoscalar giant quadrupole resonance

    Microsoft Academic Search

    A. Shevchenko; O. Burda; J. Carter; G. R. J. Cooper; R. W. Fearick; S. V. Förtsch; H. Fujita; Y. Fujita; Y. Kalmykov; D. Lacroix; J. J. Lawrie; P. von Neumann-Cosel; R. Neveling; V. Yu. Ponomarev; A. Richter; E. Sideras-Haddad; F. D. Smit; J. Wambach

    2009-01-01

    Fine structure in the region of the isoscalar giant quadrupole resonance (ISGQR) in Ni58, Y89, Zr90, Sn120, Er166, and Pb208 has been observed in high-energy-resolution (DeltaE1\\/2~=35-50 keV) inelastic proton scattering measurements at E0=200 MeV at iThemba LABS. Calculations of the corresponding quadrupole excitation strength functions performed within models based on the random-phase approximation (RPA) reveal similar fine structure when the

  15. Mitigating radiation loads in Nb(3)Sn quadrupoles for LHC upgrades

    SciTech Connect

    Mokhov, N.V.; Rakhno, I.L.; /Fermilab

    2006-08-01

    Challenging beam-induced energy deposition issues are addressed for the next generation of the LHC high-luminosity interaction regions based on Nb{sub 3}Sn quadrupoles. Detailed MARS15 Monte Carlo energy deposition calculations are performed for various coil diameters, thicknesses and materials of the inner absorber at a field gradient of 200 T/m. It is shown that using the inner absorber made of tungsten-based materials can make the final focus superconducting quadrupoles compatible with a luminosity of 10{sup 35} cm{sup -2}s{sup -1}.

  16. 3 mm Anisotropy Measurement: On the Quadrupole Component in theCosmic Background Radiation

    SciTech Connect

    Lubin, Philip M.; Epstein, Gerald L.; Smoot, George F.

    1982-11-01

    We have mapped the large-scale anisotropy in the cosmic background radiation at 3 mm wavelength using a liquid-helium-cooled balloon-borne radiometer sensitive enough to detect the dipole in one gondola rotation (1 minute). Statistical errors on the dipole and quadrupole components are below 0.1 mK with less than 0.1 m K galactic contribution. We find a dipole consistent with previous measurements but disagree with recent quadrupole reports. The measurement is also useful in searching for spectral distortions.

  17. On psychological understanding

    Microsoft Academic Search

    C. G. Jung

    1915-01-01

    Discusses the psychology of understanding delusions. Two types of delusions have been proposed: positive wish-fulfilling delusions of grandeur; and negative delusions of persecution and depreciation. The 2 kinds of understanding are: (1) retrospective understanding consisting in an essentially reductive method, and (2) prospective understanding consisting of a constructive method. Constructive understanding is explained as subjective, not scientific, and as decomposing

  18. DESIGN AND STUDY OF A SUPERFERRIC MODEL DIPOLE AND QUADRUPOLE MAGNETS FOR THE GSI FAST-PULSED SYNCHROTRON SIS100

    Microsoft Academic Search

    A. Kovalenko; N. Agapov; V. Bartenev; A. Donyagin; I. Eliseeva; H. Khodzhibagiyan; G. Kuznetsov; A. Smirnov; M. Voevodin; G. Moritz

    2004-01-01

    New experimental results from the investigation of a model superferric Nuclotron-type dipole and quadrupole magnets are presented. The magnets operate at pulse repetition rate f = 1 Hz, providing the peak magnetic field B = 2 T and the field gradient G = 34 T\\/m in the dipoles and quadrupoles respectively. The superconducting coil is made from a hollow multi-filamentary

  19. Abstract--High gradient quadrupoles are being developed by the US-LHC Accelerator Project for the LHC interaction

    E-print Network

    Large Hadron Collider Program

    Abstract-- High gradient quadrupoles are being developed by the US-LHC Accelerator Project these magnets against excessively high coil temperatures and coil voltage to ground as a result of a spontaneous interaction regions will consist of high gradient quadrupoles from KEK and the US-LHC accelerator project

  20. ENGINEERING DESIGN OF HTS QUADRUPOLE FOR FRIB* John P. Cozzolino, Michael Anerella, Arup K. Ghosh, Ramesh C. Gupta, William Sampson,

    E-print Network

    Gupta, Ramesh

    110 mm Design Gradient 15 T/m Magnetic Length 600 mm Coil Overall Length 680 mm Yoke Length 546 mmENGINEERING DESIGN OF HTS QUADRUPOLE FOR FRIB* John P. Cozzolino, Michael Anerella, Arup K. Ghosh, NSCL, Michigan State University, East Lansing, MI 48824, USA Abstract The coils of the first quadrupole

  1. arXiv:astro-ph/0406496v122Jun2004 A Low CMB Quadrupole from Dark Energy Isocurvature Perturbations

    E-print Network

    Hu, Wayne

    arXiv:astro-ph/0406496v122Jun2004 A Low CMB Quadrupole from Dark Energy Isocurvature Perturbations, Chicago IL 60637 We explicate the origin of the temperature quadrupole in the adiabatic dark energy model and explore the mechanism by which scale invariant isocurvature dark energy perturbations can lead to its

  2. Nuclear Physics

    E-print Network

    E. M. Henley; J. P. Schiffer

    1998-07-15

    Nuclear Physics is the branch of physics that deals with the properties and structure of matter on the hadronic level. In this article we review briefly the history of this field, which has a major role in the development of our understanding of nature. We then proceed to give an outline of a current perspective of the field and of some of the issues that are now on its frontiers.

  3. The Department of PhysicsPRESENTS Nuclear Physics & Society

    E-print Network

    Gilfoyle, Jerry

    The Department of PhysicsPRESENTS Nuclear Physics & Society A free, four-day short course on nuclear physics and public policy for anyone who wants to better understand nuclear power nuclear weapons P.M. Applications of Nuclear Physics on Earth: Nuclear power, weapons, and nuclear medicine. Topics

  4. Experimental verification of resonance instability bands in quadrupole doublet focusing channels

    NASA Astrophysics Data System (ADS)

    Fukushima, K.; Ito, K.; Okamoto, H.; Yamaguchi, S.; Moriya, K.; Higaki, H.; Okano, T.; Lund, S. M.

    2014-01-01

    The tabletop plasma trap experiment named "S-POD" is employed to explore the stability of intense charged-particle beams focused by a series of quadrupole doublet cells. S-POD is a compact linear Paul-trap, where we generate a single-species non-neutral ion plasma that can approximately reproduce the collective motion of an intense beam focused by periodic linear forces. Unlike conventional beam-dynamics experiments relying on large-scale transport channels and accelerators, it is straightforward in S-POD to control the functional form of quadrupole beam focusing over a wide range of variation to explore a variety of quadrupole focusing lattices. We systematically measure the loss rate of trapped particles as a function of bare betatron tune to locate resonance bands in which the plasma becomes unstable. It is confirmed that a few bands of coherent resonances appear depending on the beam intensity. When there is an imbalance between the horizontal and vertical focusing, those instability bands split. Experimental results indicate that the instability band is relatively insensitive to the phase of quadrupole focusing element placement within the doublet configuration over a significant range of parameters. Experimental observations are compared with transverse slice particle-in-cell simulations carried out using the Warp code.

  5. Competition between Quadrupole and Magnetic Kondo Effects in Non-Kramers Doublet Systems

    NASA Astrophysics Data System (ADS)

    Kusunose, Hiroaki; Onimaru, Takahiro

    2015-03-01

    We discuss possible competition between magnetic and quadrupole Kondo effects in non-Kramers doublet systems in cubic symmetry. The quadrupole Kondo effect leads to non-Fermi-liquid (NFL) ground state, while the magnetic one favors ordinary Fermi-liquid (FL) ground state. In terms of the j-j coupling scheme, we argue that the orbital fluctuation must develop in the vicinity of the NFL-FL boundary. A change of temperature dependence of the f-electron entropy in both the FL and NFL regimes is demonstrated by the Wilson's numerical renormalization-group (NRG) method on the basis of the extended two-channel Kondo exchange model. We present implications to PrT2X20 (T=Ti, V, Ir; X=Al, Zn) systems which exhibit both quadrupole ordering and peculiar superconductivity. We discuss how the magnetic field lifts the non-Kramers degeneracy. Our model also represents the alternative FL state accompanied by a free magnetic spin, as a consequence of stronger competition between the magnetic and the quadrupole Kondo effects.

  6. The importance of quadrupole sources in prediction of transonic tip speed propeller noise

    Microsoft Academic Search

    D. B. Hanson; M. R. Fink

    1978-01-01

    A theoretical analysis is presented for the harmonic noise of high speed, open rotors. Far field acoustic radiation equations based on the Ffowcs-Williams\\/Hawkings theory are derived for a static rotor with thin blades and zero lift. Near the plane of rotation, the dominant sources are the volume displacement and the rho U(2) quadrupole, where u is the disturbance velocity component

  7. The importance of quadrupole sources in prediction of transonic tip speed propeller noise

    Microsoft Academic Search

    D. B. Hanson; M. R. Fink

    1979-01-01

    A theoretical analysis is presented for the harmonic noise of high speed, open rotors. Far field acoustic radiation equations based on the Ffowcs Williams\\/Hawkings theory are derived for a static rotor with thin blades and zero lift. Near the plane of rotation, the dominant sources are the volume displacement and the varrhou2 quadrupole, where u is the disturbance velocity component

  8. The feasibility of Quadrupole Dip Imaging with PMRI: focus on multiple sclerosis 

    E-print Network

    Jeter, Edward Hilton

    2013-02-22

    . . ACKNOWLEDGEMF2&S . . TABLE OF CONTENTS . . LIST OF FIGURES . CHAPTER I INTRODUCIION . . II MEDICAL IMAGING. . III MAGNETIC RESONANCE IMAGING. IV RELAXOMETRY WITH PREPOLARIZED MRI . V RELAXOMETRY OF PROTEIN SYSTEMS. . . VI QUADRUPOLE INTERACIIONS.... . . . . . . . I 4 . . . . . . . . 3 I . . . . . . . . 7 1 . . . . . . . . 72 . . . . . . . . 74 . . . . . . . . 74 . . . . . . . 75 CHAPTER I INTRODUCTION The focus of this research is to develop medical imaging techniques that are more speci6c and less...

  9. Analysis of electric quadrupole radiation in the time domain: application to large-current radiators

    Microsoft Academic Search

    RAFAEL GOMEZ; JUAN A. MORENTE

    1985-01-01

    In this paper, the fields created by a hertzian electric quadrupole fed by a non-sinusoidal signal are analysed in the time domain. The results are compared with those obtained for an electric dipole and are applied to the study of the field created by the practical antenna, the large-current radiator.

  10. Measurement of lithium isotope ratios by quadrupole-ICP-MS: application to seawater and natural carbonates

    E-print Network

    Weston, Ken

    Measurement of lithium isotope ratios by quadrupole-ICP-MS: application to seawater and natural method for lithium isotope ratio (7 Li/6 Li) determinations with low total lithium consumption ( of natural carbonates (foraminifera) containing 1 to 2 ppm lithium. This lithium separation method

  11. Magnetic field measurements of quadrupoles in the High-Current Experiment

    NASA Astrophysics Data System (ADS)

    Seidl, P. A.; Kireeff Covo, M.; Baca, D.; Faltens, A.; Molvik, A. W.; Ritchie, G.; Sabbi, G.; Shuman, D.

    2005-05-01

    The High-Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. Four pulsed magnetic quadrupoles are being used to study gas and electron effects with a 0.2 A, 1-MeV K + beam. The magnets, originally designed and built for a prototype pulsed magnetic quadrupole array, have an elliptical beam tube (6×10 cm) and iron yoke. The magnet coil and field length are ?31 cm, and operating gradients are 10-40 T/m. To establish that the field quality of the prototype quadrupoles is satisfactory for the experiments, a 1-cm pickup loop was used to measure the flux Br( ?) at the magnet mid-plane and also at the lead and return ends. A longer probe was used to measure the integrated flux of B ?( ?) along the magnet. The field quality appears satisfactory for the short transport experiments through these quadrupoles.

  12. Parametric Analysis of Forces and Stresses in Superconducting Quadrupole Sector Windings

    Microsoft Academic Search

    P Fessia; F Regis; E Todesco

    2009-01-01

    We first present a review of the existing analytical equations for electromagnetic forces and stress in a sector coil quadrupole, evaluating their extent of application in function of the coil geometrical layout. We analyze the distribution of stress provided on the coil retaining structure as well as on the coil mid plane, this one related to the degradation of critical

  13. Parametric Analysis of Forces and Stresses in Superconducting Quadrupole Sector Windings

    Microsoft Academic Search

    P Fessia; F Regis; E Todesco

    2008-01-01

    We first present a review of the existing analytical equations for electromagnetic forces and stress in a sector coil quadrupole, evaluating their extent of application in function of the coil geometrical layout. We analyze the distribution of stress provided on the coil retaining structure as well as on the coil mid plane, this one related to the degradation of critical

  14. Estimate of Skew Quadrupole Field in Tevatron Dipoles due to Creep

    Microsoft Academic Search

    M. Syphers

    The strong systematic transverse coupling observed in the Tevatron is believed to have developed over time as fiberglass spacers used in the magnet design have crept into a compressed state during the lifetime of the accelerator. Below we present a simple model of the Tevatron dipole magnet using the method of magnetic images to calculate the skew quadrupole coecient, a1,

  15. Development of Radiation Resistant Quadrupoles Based on High Temperature Superconductors for the Fragment Separator

    Microsoft Academic Search

    R. Gupta; M. Harrison; A. Zeller

    A very high radiation dose on the quadrupole magnets in RIA's fragment separator makes them as one of the most challenging element in the RIA proposal. To overcome this problem, a new design is proposed that reduces both radiation dose and heat load by an order of magnitude. The proposed warm iron design will use commercially available High Temperature Superconductor

  16. Guide lines for the design of very large aperture quadrupole magnets

    Microsoft Academic Search

    A. Daeel; J. P. Jorda; F. Kircher; C. Mayri

    1996-01-01

    Very large aperture quadrupole magnets have been recently considered as possible spectrometers on high energy colliders. The interesting characteristics are zero field on beam axis, low fields at small angles, transverse field at large angles. Dimension range is 1 m to 5 m for clear bore and 2 m to 8 m for length; typical maximum field is 2.5 T.

  17. DESIGN OF A THIN QUADRUPOLE TO BE USED IN THE AGS SYNCHROTRON

    SciTech Connect

    TSOUPAS,N.; AHRENS, L.; ALFORQUE, R.; BAI, M.; BROWN, K.; COURANT, E.; ET AL.

    2007-06-25

    The Alternating Gradient Synchrotron (AGS) employs two partial helical snakes[l] to preserve the polarization of the proton beam during acceleration. In order to compensate for the focusing effect of the partial helical snakes on the beam optics in the AGS during acceleration of the beam, we introduced eight quadrupoles in straight sections of the AGS at the proximity of the partial snakes. At injection energies, the strength of each quad is set at a high value, and is ramped down to zero as the effect of the snakes diminishes by the square of beam's rigidity. Four of the eight compensation quadrupoles had to be placed in very short straight sections -30 cm in length, therefore the quadruples had be thin with an overall length of less than 30 cm. In this paper we will discus: (a) the mechanical and magnetic specifications of the ''thin'' quadrupole. (b) the method to minimize the strength of the dodecapole harmonic, (c) the method to optimize the thickness of the laminations that the magnet iron is made, (d) mechanical tolerances of the magnet, (e) comparison of the measured and calculated magnetic multipoles of the quadrupole.

  18. Determination of semduramicin in poultry feed at authorized level by liquid chromatography single quadrupole mass spectrometry

    Microsoft Academic Search

    María José González de la Huebra; Ursula Vincent; Christoph von Holst

    2010-01-01

    A novel liquid chromatography single quadrupole mass spectrometry (LC–MS) method for the determination of the feed additive semduramicin, in poultry feed, was developed and single-laboratory validated. This work was selected as a real case scenario to outline the different steps that may be needed whenever the standardisation of an analytical method in the field of methods of analysis for animal

  19. Radio frequency quadrupole confined gas discharge for a high power argon-ion laser

    Microsoft Academic Search

    M. Iberler; V. Arsov; R. Berezov; J. Jacoby; Ch. Teske

    2005-01-01

    A new conept for the generation of a gas discharge plasma is under investigation. This new gas discharge is based on a high frequency plasma which is a electrode less configuration. To achieve a high density, the plasma is confined by a magnetic quadrupole field. The energy deposition into the plasma was performed by cw-inductive coupling per antenna. The plasma

  20. The Fortuitous Latitude of the Pierre Auger Observatory and Telescope Array for Reconstructing the Quadrupole Moment

    NASA Astrophysics Data System (ADS)

    Denton, Peter B.; Weiler, Thomas J.

    2015-03-01

    Determining anisotropies in the arrival directions of cosmic rays at the highest energy is an important task in astrophysics. It is common and useful to partition the sky into spherical harmonics as a measure of anisotropy. The two lowest nontrivial spherical harmonics, the dipole and the quadrupole, are of particular interest, since these distributions encapsulate a dominant single source and a plane of sources, as well as offering relatively high statistics. The best experiments for the detection of ultra high energy cosmic rays currently are all ground-based, with highly nonuniform exposures on the sky resulting from the fixed experimental locations on the Earth. This nonuniform exposure increases the complexity and error in inferring anisotropies. It turns out that there is an optimal latitude for an experiment at which nonuniform exposure does not diminish the inference of the quadrupole moment. We derive the optimal latitude and find that (presumably by a fortuitous coincidence) this optimal latitude runs through the largest cosmic ray experiment, the Pierre Auger Observatory (PAO) in the Southern Hemisphere, and close to the largest cosmic ray experiment in the Northern Hemisphere, the Telescope Array (TA). Consequently, assuming a quadrupole distribution, PAO and TA can reconstruct the cosmic ray quadrupole distribution to a high precision without concern for their partial sky exposure.

  1. Quantum manifestations of classical stochasticity in the wave functions of quadrupole vibrations of nuclei

    SciTech Connect

    Bolotin, Yu.L.; Gonchar, V.Yu.; Tarasov, V.N. [National Research Center Khar`kov Physicotechnical Institute (Ukraine)

    1995-09-01

    Quantum manifestations of classical stochasticity in the structure of the stationary wave functions of highly excited states of the Hamiltonian of quadrupole vibrations are studied. Correlations between the structure of the wave functions and the type of classical motion are found in the regularity-chaos-regularity transition. 28 refs., 8 figs., 3 tabs.

  2. Cyclotron-resonance maser in a periodically loaded quadrupole transmission line Y. Leibovitch and E. Jerby*

    E-print Network

    Jerby, Eli

    Cyclotron-resonance maser in a periodically loaded quadrupole transmission line Y. Leibovitch and E; revised manuscript received 17 February 1999 A cyclotron-resonance maser CRM is implemented in a periodic, 84.40.Ik, 84.47. w I. INTRODUCTION Cyclotron-resonance masers CRMs and gyrotrons are known as high

  3. Physical origin of the quadrupole out-of-plane magnetic field in Hall-magnetohydrodynamic reconnection

    E-print Network

    Physical origin of the quadrupole out-of-plane magnetic field in Hall-magnetohydrodynamic-of-plane component of the magnetic field inside a reconnection region is seen as an important signature of the Hall-magnetohydrodynamic and that the Petschek5 fast-reconnection mechanism cannot be realized in resistive magnetohydrodynamic MHD with uniform

  4. Interference with negative particle sampling due to formation of positive ions in a quadrupole mass spectrometer

    NASA Technical Reports Server (NTRS)

    Kuehn, D. G.; Chanin, L. M.

    1980-01-01

    A quadrupole mass spectrometer has been utilized to study active discharges containing Cs vapor. Production of positive ions by electron impact within the mass spectrometer and subsequent secondary electron emission from cesiated surfaces produced spurious or pseudonegative ion signals which interfered with attempts to sample negative ions from the plasma. These effects may also occur in other gas discharge systems.

  5. The quadrupole resonator:Construction, RF System Field Calculations and First Applications

    Microsoft Academic Search

    Enrico Chiaveri; E Häbel; E Mahner; J M Tessier

    1998-01-01

    The quadrupole resonator allows measurement of the RF properties of superconducting (sc) films deposited on disk-shaped metallic substrates. We describe the construction of the apparatus, the brazing and electron-beam welding procedures, the arrangements for compensating mechanical tolerances of samples and for assuring reproducible sample illumination. We explain the special features of the RF sy stem and give the results of

  6. Noble gas detection using resonance ionization spectroscopy and a quadrupole mass spectrometer

    Microsoft Academic Search

    C. H. Chen; G. S. Hurst

    1983-01-01

    The technique of Resonance Ionization Spectroscopy (RIS) is being extended to develop a means for counting individual atoms of a selected isotope of a noble gas. In this method, lasers are used for RIS to obtain atomic species (Z) selectivity and a small quadrupole mass spectrometer provides isotopic (A) selectivity. A progress report on the objective of counting each atom

  7. A new high-gradient correction quadrupole for the Fermilab luminosity upgrade

    SciTech Connect

    Mantsch, P.; Carson, J.; Riddiford, A.; Lamm, M.J.

    1989-03-01

    Special superconducting correction quadrupoles are needed for the luminosity upgrade of the Fermilab Tevatron Collider. These correctors are part of the low-beta system for the interaction regions at B/phi/ and D/phi/. The requirements are high gradient and low current. A quadrupole has been designed that meets the operating gradient of 0.63 T/cm at 1086 A. The one-layer quadrupole is wound with a cable consisting of five individually insulated rectangular strands. The five strands are overwrapped with Kapton and epoxy impregnated glass tape. The winding, curing and collaring of the magnet is accomplished in the same manner as Tevatron-like magnets using Rutherford style cable. Once the magnet is complete the five strands are connected in series. A prototype quadrupole has been assembled and tested. The magnet reached a plateau current of 1560 A corresponding to a gradient of 0.91 T/cm without training. The measured field harmonics are substantially better than required. 8 refs., 6 figs., 4 tabs.

  8. A HYBRID QUADRUPOLE DESIGN FOR THE RAL FRONT END TEST STAND (FETS)

    Microsoft Academic Search

    C. Plostinar; M. Clarke-Gayther; S. Jago

    The Front End Test Stand project being constructed at Rutherford Appleton Laboratory (RAL) aims to deliver a high current (60 mA) H- chopped ion beam, at 3 MeV and 50 pps. The main components of FETS are the H - ion source, the Low Energy Beam Transport line (LEBT), the Radio Frequency Quadrupole (RFQ), the Medium Energy Transport (MEBT) line

  9. Electron interactions with a heavy-ion beam in HCX quadrupole magnetic fields experimental planning

    Microsoft Academic Search

    A. W. Molvik; R. H. Cohen; P. A. Seidl; S. M. Lund; F. M. Bieniosek; L. R. Prost

    2001-01-01

    Barely trapped electrons can originate from beams or UV radiation impinging on walls, and deeply trapped electrons can originate from beam ionization of gas. Electrons are electrostatically trapped by the beam and can reduce its potential from the nominal 5 kV. Since the quadrupole transport is primarily balancing the beam space charge, a change in potential causes a mismatch in

  10. Laser cooling and sympathetic cooling in a linear quadrupole rf trap 

    E-print Network

    Ryjkov, Vladimir Leonidovich

    2005-02-17

    An investigation of the sympathetic cooling method for the studies of large ultra-cold molecular ions in a quadrupole ion trap has been conducted.Molecular dynamics simulations are performed to study the rf heating mechanisms in the ion trap...

  11. Design study of a superconducting insertion quadrupole magnet for the Large Hadron Collider

    Microsoft Academic Search

    A. Yamamoto; K. Tsuchiya; N. Higashi; T. Nakamoto; T. Ogitsu; N. Ohuchi; T. Shintomi; A. Terashima; G. Kirby; R. Ostojic; T. M. Taylor

    1997-01-01

    The conceptual design study of a high gradient superconducting insertion quadrupole magnet has been carried out in collaboration between KEK and CERN for the Large Hadron Collider (LHC) to be built at CERN. A model magnet design has been optimized to provide a nominal design field gradient of 240 T\\/m with a bore aperture of 70 mm and an operational

  12. Development and Coil Fabrication for the LARP 3.7-m Long Nb3Sn Quadrupole

    SciTech Connect

    Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidize, G.; Dietderich, D.; Felice, H.; Ferracin, P.; Ghosh, A.; Hafalia, R.; Hannaford, R.; Jochen, G.; Kashikhin, V.V.; Kovach, P.; Lamm, M.; Lietzke, A.; McInturff, A.; Muratore,, J.; Nobreaga, F.; Novitsky, I.; Peggs, S.; Prestemon, S.; Sabbi, G. L.; Schmalzle, J.; Turrioni, D.; Wanderer, P.; Whitson, G.; Zlobin, A. V.

    2008-08-17

    The U.S. LHC Accelerator Research Program (LARP) has started the fabrication of 3.7-m long Nb{sub 3}Sn quadrupole models. The Long Quadrupoles (LQ) are 'Proof-of-Principle' magnets which are to demonstrate that Nb{sub 3}Sn technology is mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, developed at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. The plans for the LQ R&D and a design update are presented and discussed in this paper. The challenges of fabricating long accelerator-quality Nb{sub 3}Sn coils are presented together with the solutions adopted for the LQ coils (based on the TQ experience). During the fabrication and inspection of practice coils some problems were found and corrected. The fabrication at BNL and FNAL of the set of coils for the first Long Quadrupole is in progress.

  13. Correlation of experimental data and three-dimensional finite element modeling of a spinning quadrupole

    SciTech Connect

    Lorimer, W.L.; Lieu, D.K. [California Univ., Berkeley, CA (United States). Dept. of Mechanical Engineering; Hull, J.R.; Mulcahy, T.M.; Rossing, T.D. [Argonne National Lab., IL (United States)

    1993-09-01

    A permanent magnet quadrupole spinning over an aluminum disk was constructed, and drag torque was measured for various speeds and gap sizes. The experiment was modeled using a three-dimensional finite element program. Experimental and analytical results were compared, and the effect of magnet polarity was determined.

  14. Coil Creep and Skew-Quadrupole Field Components in the Tevatron

    SciTech Connect

    Annala, G.; Harding, D.J.; Syphers, M.J.; /Fermilab

    2011-07-11

    During the start-up of Run II of the Tevatron Collider program, several issues surfaced which were not present, or not seen as detrimental, during Run I. These included the repeated deterioration of the closed orbit requiring orbit smoothing every two weeks or so, the inability to correct the closed orbit to desired positions due to various correctors running at maximum limits, regions of systematically strong vertical dipole corrections, and the identification of very strong coupling between the two transverse degrees-of-freedom. It became apparent that many of the problems being experienced operationally were connected to a deterioration of the main dipole magnet alignment, and remedial actions were undertaken. However, the alignment alone was not enough to explain the corrector strengths required to handle transverse coupling. With one exception, strong coupling had generally not been an issue in the Tevatron during Run I. Based on experience with the Main Ring, the Tevatron was designed with a very strong skew quadrupole circuit to compensate any quadrupole alignment and skew quadrupole field errors that might present themselves. The circuit was composed of 48 correctors placed evenly throughout the arcs, 8 per sector, evenly placed in every other cell. Other smaller circuits were installed but not initially needed or commissioned. These smaller circuits were composed of individual skew quadrupole correctors on either side of the long straight sections. These circuits were tuned by first bringing the horizontal and vertical tunes near each other. The skew quadrupoles were then adjusted to minimize tune split, usually to less than 0.003. Initially, the main skew quad circuit (designated T:SQ) could accomplish this global decoupling with only 4% of its possible current, and the smaller circuits were not required at all. The start-up of Run Ib was complicated by what was later discovered to be a rolled triplet quadrupole magnet in one of the Interaction Regions. This led to a reduction in luminosity of nearly 50%, as well as operational confusion until it was uncovered. By the time Collider Run II began, the current needed on the main SQ circuit had increased to 60% of its maximum value. Some of the smaller circuits were also needed to fully decouple the tunes. With this history, several studies were performed early in Run II to search for strong local coupling sources like the triplet quadrupole, but without success. The strong corrector settings were indicative of a much larger problem than a single rolled magnet, and the locality of the error was hard to deduce from the setting of a global correction system. Several possible reasons for the increase in coupling were investigated.

  15. Proposed mechanisms for the fragmentation of doubly allylic alkenamides (tingle compounds) by low energy collisional activation in a triple quadrupole mass spectrometer.

    PubMed

    Hiserodt, Richard D; Pope, Barry M; Cossette, Michael; Dewis, Mark L

    2004-10-01

    Tingle compounds are a class of alkenamides with organoleptic properties that include a numbing or a pins and needles effect that is generally perceived on the lips and in the mouth when consumed. They occur in nature in a number of botanical species. Spilanthol and Pellitorine are important examples of tingle compounds. A number of homologs and analogs were synthesized to study the effect of chain length, double bond location, and amide moiety on the tingle effect. This also provided the opportunity to study the behavior of these compounds in the collision cell of a triple quadrupole mass spectrometer. The doubly allylic 2E,6Z-alkenamides, which made up the largest class studied, fragmented in a characteristic way to produce a distonic radical cation and a cyclopropene cation. Mechanisms for the formation of these ions are proposed. The mechanisms are supported by energy-resolved mass spectrometric data, the analysis of deuterated analogs and homologs that are not doubly allylic, and exact mass measurements. Exceptions to the proposed mechanisms are also presented. These data represent the first attempt to apply mechanistic principles to the product ions observed in the MS/MS spectra of these compounds. The authors believe the results of this study will facilitate the identification of these and similar compounds and contribute to the fundamental understanding of the behavior of alkenamides in the collision cell of a triple quadrupole mass spectrometer. PMID:15465359

  16. Space-charge effects with mass-selective axial ejection from a linear quadrupole ion trap.

    PubMed

    Qiao, Hui; Gao, Cong; Mao, Dunmin; Konenkov, Nikolai; Douglas, D J

    2011-12-15

    Methods to reduce mass shifts caused by space charge with mass-selective axial ejection from a linear quadrupole ion trap are investigated. For axial ejection, dipole excitation is applied to excite ions at q???0.85. The trapping radiofrequency (rf) voltage is scanned to bring ions of different m/z values into resonance for excitation. In the fringing field at the quadrupole exit, excited ions gain axial kinetic energy, overcoming the trapping potential, and are ejected from the trap. Space charge causes the frequencies of ion oscillation to decrease. Thus, greater rf voltages are required to bring ions into resonance for excitation and ejection, and the ions shift to higher apparent masses in a mass spectrum. At the same time, the peaks broaden, lowering resolution. The effects of injection q value, ejection q value, excitation amplitude, quadrupole dc voltages applied to the electrodes, applying an rf voltage to the exit lens, and scan speed, on mass shifts have been studied experimentally. Most experiments were done with only ions of protonated reserpine (m/z 609.3 and its isotopic peaks) in the trap. Some experiments were done with ions of protonated reserpine and ions of m/z 622 in the trap. In general, the mass shifts are reduced with higher ejection q values, higher excitation amplitudes, with quadrupole dc applied, and at higher scan speeds. The application of quadrupole dc appears to increase the ion cloud temperature, which lowers mass shifts. Thus, a proper choice of operating conditions can reduce, but not eliminate, mass shifts caused by space charge. PMID:22095499

  17. Hybridized quadrupole-dipole exciton effects in a Cu2O -organic heterostructure

    NASA Astrophysics Data System (ADS)

    Roslyak, Oleksiy; Birman, Joseph L.

    2007-06-01

    In the present work, we discuss resonant hybridization of the 1S quadrupole Wannier-Mott exciton (WE) in a Cu2O quantum well with the Frenkel dipole exciton in an adjacent layer of organic DCM2:CA:PA. The coupling between excitons is due to interaction between the gradient of electric field induced by the DCM2 Frenkel exciton (FE) and the quadrupole moment of the 1S transition in the cuprous oxide. The specific choice of the organic allows us to use the mechanism of “solid state solvation” [C. Madigan and V. Bulovic, Phys. Rev. Lett. 91, 247403 (2003)] to dynamically tune the WE and FE into resonance for ?3.3ns (comparable with the big lifetime of the WE) of the “slow” phase of the solvation. The quadrupole-dipole hybrid utilizes the big oscillator strength of the FE, along with the big lifetime of the quadrupole exciton, unlike dipole-dipole hybrid exciton which utilizes the big oscillator strength of the FE and big radius of the dipole allowed WE. Due to the strong spatial dispersion and big mass of the quadrupole WE, the hybridization is not masked by the kinetic energy or the radiative broadening. The lower branch of the hybrid dispersion exhibits a pronounced minimum and may be used in applications. Also, we investigate and report noticeable change in the coupling due to an induced “Stark effect” from the strong local electric field of the FE. We investigated the fine energy structure of the quantum well confined ortho and para excitons in cuprous oxide.

  18. Profiling the metabolism of astragaloside IV by ultra performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry.

    PubMed

    Cheng, Xu-Dong; Wei, Ming-Gang

    2014-01-01

    Astragaloside IV is a compound isolated from the Traditional Chinese Medicine Astragalus membranaceus, that has been reported to have bioactivities against cardiovascular disease and kidney disease. There is limited information on the metabolism of astragaloside IV, which impedes comprehension of its biological actions and pharmacology. In the present study, an ultra-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS)-based approach was developed to profile the metabolites of astragaloside IV in rat plasma, bile, urine and feces samples. Twenty-two major metabolites were detected. The major components found in plasma, bile, urine and feces included the parent chemical and phases I and II metabolites. The major metabolic reactions of astragaloside IV were hydrolysis, glucuronidation, sulfation and dehydrogenation. These results will help to improve understanding the metabolism and reveal the biotransformation profiling of astragaloside IV in vivo. The metabolic information obtained from our study will guide studies into the pharmacological activity and clinical safety of astragaloside IV. PMID:25407723

  19. Consequences of omitting spin-orbit partner configurations for B (E 2 ) values and quadrupole moments in nuclei

    NASA Astrophysics Data System (ADS)

    Zamick, L.; Sharon, Y. Y.; Robinson, S. J. Q.; Harper, M.

    2015-06-01

    Shell-model calculations of B (E 2 )'s and quadrupole moments in the even-even nuclei in the g9 /2 shell region below 100Sn are hampered by the fact that the inclusion of the g7 /2 configuration will lead to model spaces that are too large to handle. Understanding the impact of specific orbit wave functions in large-scale shell-model (LSSM) calculations helps to shed light on the validity of the results that are obtained. We therefore examine lighter nuclei in the beginning of the f p region where one can normally include all the orbitals, f7 /2,p3 /2,p1 /2, and f5 /2, for both protons and neutrons. We perform such calculations but then take a step back and exclude the f5 /2 orbital. By comparing the results of the two calculations we can hope to get insight into the importance of the missing spin-orbital partner in other regions.

  20. Nuclear Medicine CT Angiography

    E-print Network

    Ford, James

    rotation is based at the Palo Alto VA Medical Center and gives the cardiology fellow experience. Understand the indications for exercise treadmill testing and specific nuclear cardiology tests, safe use patient and learn the importance of physical and pharmacologic stress in nuclear cardiology 3. Interpret

  1. Multisectional linear ion trap and novel loading method for optical spectroscopy of electron and nuclear transitions.

    PubMed

    Sysoev, Alexey A; Troyan, Victor I; Borisyuk, Peter V; Krasavin, Andrey V; Vasiliev, Oleg S; Palchikov, Vitaly G; Avdeev, Ivan A; Chernyshev, Denis M; Poteshin, Sergey S

    2015-01-01

    There is a growing need for the development of atomic and nuclear frequency standards because of the important contribution of methods for precision time and frequency measurements to the development of fundamental science, technology, and the economy. It is also conditioned by their potential use in optical clocks and quantum logic applications. It is especially important to develop a universal method that could allow one to use ions of most elements effectively (including ones that are not easily evaporated) proposed for the above-mentioned applications. A linear quadrupole ion trap for the optical spectroscopy of electron and nuclear transitions has been developed and evaluated experimentally. An ion source construction is based on an ultra-high vacuum evaporator in which a metal sample is subjected to an electron beam of energy up to 1?keV, resulting in the appearance of gaseous atoms and ions of various charge state. The linear ion trap consists of five successive quadrupole sections including an entrance quadrupole section, quadrupole mass filter, quadrupole ion guide, ion-trap section, and exit quadrupole section. The same radiofrequency but a different direct current voltage feeds the quadrupole sections. The instrument allows the mass and energy selected trapping of ions from ion beams of various intensities and their localization in the area of laser irradiation. The preliminary results presented show that the proposed instrument and methods allow one to produce effectively up to triply charged thorium ions as well as to trap ions for future spectroscopic study. The instrument is proposed for future use in optical clocks and quantum logic application development. PMID:25906029

  2. Asymmetry of hydrogen lines in plasmas utilizing a statistical description of ion-quadrupole interaction in Mozer-Baranger limit

    NASA Astrophysics Data System (ADS)

    Halenka, J.

    1990-03-01

    Hydrogen line Stark profiles are calculated in the static ion approximation including the ion-quadrupole interaction and the quadratic Stark effect. The statistics of the ion-quadrupole interaction is evaluated in the Mozer-Baranger limit taking into account the screening and the ion correlations. The generalized function B ?(?) exceeds several times the ordinary Chandrasekhar and von Neumann function B(?)= B ?=0(?) (i.e. B ?(?) at ?=0) and in the same proportion increases the importance of the ion-quadrupole interaction. For n e ranging from 1016 to 1018 cm-3, calculated parameters of the asymmetry and shift of H ? agree well with measurements by different authors.

  3. Trapping of Electron Cloud LLC/Cesrta Quadrupole and Sextupole Magnets

    SciTech Connect

    Wang, L; Pivi, M.; /SLAC

    2011-08-18

    The Cornell Electron Storage Ring (CESR) has been reconfigured as an ultra low emittance damping ring for use as a test accelerator (CesrTA) for International Linear Collider (ILC) damping ring R&D [1]. One of the primary goals of the CesrTA program is to investigate the interaction of the electron cloud with low emittance positron beam to explore methods to suppress the electron cloud, develop suitable advanced instrumentation required for these experimental studies and benchmark predictions by simulation codes. This paper reports the simulation of the electron-cloud formation in CESRTA and ILC quadrupole and sextupole magnets using the 3D code CLOUDLAND. We found that electrons can be trapped with a long lifetime in a quadrupole and sextupole magnet due to the mirror field trapping mechanism. We study the effects of magnet strength, bunch current, ante-chamber effect, bunch spacing effect and secondary emission yield (SEY) in great detail. The development of an electron cloud in magnets is the main concern where a weak solenoid field is not effective. Quadrupole and sextupole magnets have mirror field configurations which may trap electrons by the mirror field trapping mechanism [2]. Fig.1 shows the orbit of a trapped electron in a quadrupole magnet. The electron makes gyration motion (called transverse motion) and also moves along the field line (called longitudinal motion). At the mirror point (middle of the field line), there is a maximum longitudinal energy and minimum transverse energy. When the electron moves away from the mirror point, its longitudinal energy reduces and the transverse energy increases as the magnetic field increases. If the magnetic field is strong enough, the longitudinal energy becomes zero at one point and then the electron is turned back by the strong field. Note that the electrons are trapped in the region near the middle of the field lines. Although all quadrupole and sextupole magnets can trap electrons in principle, the trapping mechanism is also greatly sensitive to the detail dynamics of the electrons [3]. Both the positron beam and the spacing charge force of electron cloud itself play important roles. This paper reports the simulation of electron cloud in CESRTA/ILC quadrupole and sextupole magnets. Table 1 shows the main parameters used in the simulation.

  4. Understanding Food Labels

    MedlinePLUS

    ... Healthy eating for girls Understanding food labels Understanding food labels There is lots of info on food ... need to avoid because of food allergies. Other food label terms top In addition to the Nutrition ...

  5. Video Understanding Francois BREMOND

    E-print Network

    Prié, Yannick

    agency monitoring Control access and Video surveillance in building Video understanding for video CDT 05 5 Video Understanding Application Metro station surveillance Surveillance inside trains: Realtime video surveillance platform (Multitel, Be), Machine learning Visualisation: 3D animation

  6. Characterization of metabolic profile of honokiol in rat feces using liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry and (13)C stable isotope labeling.

    PubMed

    Dong, Yinfeng; Tang, Minghai; Song, Hang; Li, Rong; Wang, Chunyu; Ye, Haoyu; Qiu, Neng; Zhang, Yongkui; Chen, Lijuan; Wei, Yuquan

    2014-03-15

    As fecal excretion is one of important routes of elimination of drugs and their metabolites, it is indispensable to investigate the metabolites in feces for more comprehensive information on biotransformation in vivo. In this study, a sensitive and reliable approach based on ultra-performance liquid chromatography/quadrupole-time-of-flight-mass spectrometry (UHPLC-Q-TOF-MS) was applied to characterize the metabolic profile of honokiol in rat feces after the administration of an equimolar mixture of honokiol and [(13)C6]-labeled honokiol. Totally 42 metabolites were discovered and tentatively identified in rat feces samples, 26 metabolites were first reported, including two novel classes of metabolites, methylated and dimeric metabolites of honokiol. Moreover, this study provided basic comparative data on the metabolites in rat plasma, feces and urine, which gave better understanding of the metabolic fate of honokiol in vivo. PMID:24566334

  7. The zero-point energy correction and its effect on nuclear dynamics

    Microsoft Academic Search

    M. Girod; B. Grammaticos

    1979-01-01

    Motivated by the feasibility of microscopic calculations of the nuclear collective motion we present a practical method for calculating the zero-point energy corrections on the potential energy surfaces. For the case of quadrupole motion, as described by Bohr's Hamiltonian, the zero-point energy corrections are of vibrational and rotational nature. They can be computed in the framework of a theory based

  8. I do not Understand!

    Microsoft Academic Search

    V. Sominskii

    1991-01-01

    Like the famous satirist Mikhail Zadomyi, there is much that I, too, do not understand. He, as a writer, can be forgiven. But what about me, a professional economist who has taught economics, the organization of production, and the management of industrial enterprises for fifty years? It would seem that I should understand. But I do not understand. The state

  9. Nuclear spin-lattice relaxation times of metallic antimony at low temperatures

    NASA Astrophysics Data System (ADS)

    Genio, E. B.; Xu, J.; Lang, T.; Ihas, G. G.; Sullivan, N. S.

    1995-11-01

    We have used pulsed Nuclear Quadrupole Resonance (NQR) techniques to measure the nuclear spin-lattice relaxation times in antimony at low temperatures. High quality echoes with strong signal/noise ratios were only observed for finely powdered samples of high purity (99.9999%). The samples were carefully annealed and diluted with fine silica to below the percolation limit to minimize RF heating. The powder mixture was immersed in liquid3He to ensure good thermal contact to a sintered silver heat exchanger attached to a copper nuclear demagnetization refrigerator. We report the temperature dependence of the nuclear spin-lattice relaxation times for the multiple level nuclear spin system.

  10. First Gogny-Hartree-Fock-Bogoliubov Nuclear Mass Model

    SciTech Connect

    Goriely, S.; Hilaire, S.; Girod, M.; Peru, S. [Institut d'Astronomie et d'Astrophysique, CP-226, Universite Libre de Bruxelles, 1050 Brussels (Belgium); CEA, DAM, DIF, F-91297, Arpajon (France)

    2009-06-19

    We present the first Gogny-Hartree-Fock-Bogoliubov (HFB) model which reproduces nuclear masses with an accuracy comparable with the best mass formulas. In contrast with the Skyrme-HFB nuclear-mass models, an explicit and self-consistent account of all the quadrupole correlation energies are included within the 5D collective Hamiltonian approach. The final rms deviation with respect to the 2149 measured masses is 798 keV. In addition, the new Gogny force is shown to predict nuclear and neutron matter properties in agreement with microscopic calculations based on realistic two- and three-body forces.

  11. Atomic Energy Basics, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Atomic Energy Commission, Oak Ridge, TN. Div. of Technical Information.

    This booklet is part of the "Understanding the Atom Series," though it is a later edition and not included in the original set of 51 booklets. A basic survey of the principles of nuclear energy and most important applications are provided. These major topics are examined: matter has molecules and atoms, the atom has electrons, the nucleus,…

  12. Index to the Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Atomic Energy Commission, Oak Ridge, TN. Div. of Technical Information.

    This index was prepared for the set of 51 booklets in the "Understanding the Atom Series" published by the U. S. Atomic Energy Commission for high school students and their teachers. In addition to the index, a complete list of the series is provided in which the booklets are grouped into the categories of physics, chemistry, biology, nuclear…

  13. Hybrid quadrupole mass filter/quadrupole ion trap/time-of-flight-mass spectrometer for infrared multiple photon dissociation spectroscopy of mass-selected ions

    SciTech Connect

    Gulyuz, Kerim; Stedwell, Corey N.; Wang Da; Polfer, Nick C. [Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611 (United States)

    2011-05-15

    We present a laboratory-constructed mass spectrometer optimized for recording infrared multiple photon dissociation (IRMPD) spectra of mass-selected ions using a benchtop tunable infrared optical parametric oscillator/amplifier (OPO/A). The instrument is equipped with two ionization sources, an electrospray ionization source, as well as an electron ionization source for troubleshooting. This hybrid mass spectrometer is composed of a quadrupole mass filter for mass selection, a reduced pressure ({approx}10{sup -5} Torr) quadrupole ion trap (QIT) for OPO irradiation, and a reflectron time-of-flight drift tube for detecting the remaining precursor and photofragment ions. A helium gas pulse is introduced into the QIT to temporarily increase the pressure and hence enhance the trapping efficiency of axially injected ions. After a brief pump-down delay, the compact ion cloud is subjected to the focused output from the continuous wave OPO. In a recent study, we implemented this setup in the study of protonated tryptophan, TrpH{sup +}, as well as collision-induced dissociation products of this protonated amino acid [W. K. Mino, Jr., K. Gulyuz, D. Wang, C. N. Stedwell, and N. C. Polfer, J. Phys. Chem. Lett. 2, 299 (2011)]. Here, we give a more detailed account on the figures of merit of such IRMPD experiments. The appreciable photodissociation yields in these measurements demonstrate that IRMPD spectroscopy of covalently bound ions can be routinely carried out using benchtop OPO setups.

  14. CONSTRAINING THE QUADRUPOLE MOMENT OF STELLAR-MASS BLACK HOLE CANDIDATES WITH THE CONTINUUM FITTING METHOD

    SciTech Connect

    Bambi, Cosimo [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Barausse, Enrico, E-mail: cosimo.bambi@ipmu.jp, E-mail: barausse@umd.edu [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

    2011-04-20

    Black holes in general relativity are known as Kerr black holes and are characterized solely by two parameters, the mass M and the spin J. All the higher multipole moments of the gravitational field are functions of these two parameters. For instance, the quadrupole moment is Q = -J {sup 2}/M, which implies that a measurement of M, J, and Q for black hole candidates would allow one to test whether these objects are really black holes as described by general relativity. While future gravitational-wave experiments will be able to test the Kerr nature of these objects with very high accuracy, in this paper we show that it is possible to put constraints on the quadrupole moment of stellar-mass black hole candidates by using presently available X-ray data of the thermal spectrum of their accretion disk.

  15. Fabrication and test of LARP technological quadrupole models of TQC series

    SciTech Connect

    Bossert, R.C.; Ambrosio, G.; Andreev, N.; Barzi, E.; Chlachidze, G.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.; Nobrega, A.; Novitski, I.; /Fermilab /LBL, Berkeley /Brookhaven

    2008-08-01

    In support of the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, several two-layer technological quadrupole models of TQC series with 90 mm aperture and collar-based mechanical structure have been developed at Fermilab in collaboration with LBNL. This paper summarizes the results of fabrication and test of TQC02a, the second TQC model based on RRP Nb3Sn strand, and TQC02b, built with both MJR and RRP strand. The test results presented include magnet strain and quench performance during training, as well as quench studies of current ramp rate and temperature dependence from 1.9K to 4.5K.

  16. Core polarization for the electric quadrupole moment of neutron-rich Aluminum isotopes

    E-print Network

    Kenichi Yoshida

    2009-02-18

    The core polarization effect for the electric quadrupole moment of the neutron-rich $^{31}$Al, $^{33}$Al and $^{35}$Al isotopes in the vicinity of the island of inversion are investigated by means of the microscopic particle-vibration coupling model in which the Skyrme Hartee-Fock-Bogoliubov and quasiparticle-random-phase approximation are used to calculate the single-quasiparticle wave functions and the excitation modes. It is found that the polarization charge for the proton $1d_{5/2}$ hole state in $^{33}$Al is quite sensitive to coupling to the neutrons in the $pf$-shell associated with the pairing correlations, and that the polarization charge in $^{35}$Al becomes larger due to the stronger collectivity of the low-lying quadrupole vibrational mode in the neighboring $^{36}$Si nucleus.

  17. Ion collision crosssection measurements in quadrupole ion traps using a time-frequency analysis method.

    PubMed

    He, Muyi; Guo, Dan; Chen, Yu; Xiong, Xingchuang; Fang, Xiang; Xu, Wei

    2014-12-01

    In this study, a method for measuring ion collision crosssections (CCSs) was proposed through time-frequency analysis of ion trajectories in quadrupole ion traps. A linear ion trap with added high-order electric fields was designed and simulated. With the presence of high-order electric fields and ion-neutral collisions, ion secular motion frequency within the quadrupole ion trap will be a function of ion motion amplitude, thus a function of time and ion CCS. A direct relationship was then established between ion CCS and ion motion frequency with respect to time, which could be obtained through time-frequency analysis of ion trajectories (or ion motion induced image currents). To confirm the proposed theory, realistic ion trajectory simulations were performed, where the CCSs of bradykinin, angiotensin I and II, and ubiquitin ions were calculated from simulated ion trajectories. As an example, differentiation of isomeric ubiquitin ions was also demonstrated in the simulations. PMID:25319271

  18. The microwave spectrum and quadrupole coupling in tricarbonyl(methylcyclopentadienyl) manganese

    NASA Astrophysics Data System (ADS)

    Indris, Oliver; Stahl, Wolfgang

    The rotational spectrum of tricarbonyl(methylcyclopentadienyl) manganese has been recorded in the range from 1-23GHz using an FTMW spectrometer working on a molecular beam. This spectrum is assigned for the first time, yielding the rotational constants of the molecule and quartic centrifugal distortion constants. The fine structure due to the quadrupole interaction of the 55Mn nucleus could be solved and gave the quadrupole coupling tensor (which is compared with that of tricarbonyl(cyclopentadienyl)manganese, and the spin-rotation constants. An additional splitting of a few kHz, which could be observed for some transitions, is interpreted as arising from the internal rotation of the methyl group.

  19. Support structure design of the Nb?Sn quadrupole for the high luminosity LHC

    DOE PAGESBeta

    Juchno, M.; Anerella, M.; Ambrosio, G.; Cheng, D.; Felice, H.; Ferracin, P.; Perez, J. C.; Prin, H.; Schmalzle, J.

    2015-06-01

    New low-? quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb?Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of themore »detailed 3D numerical analysis performed in preparation for the first short model test.« less

  20. Coil End Optimization of the Nb3Sn Quadrupole for the High Luminosity LHC

    E-print Network

    Izquierdo Bermudez, S; Bossert, R; Cheng, D; Ferracin, P; Krave, ST; Perez, JC; Schmalzle, J; Yu, M

    2015-01-01

    As part of the Large Hadron Collider Luminosity upgrade (HiLumi-LHC) program, the US LARP collaboration and CERN are working together to design and build a 150 mm aperture quadrupole magnet that aims at providing a nominal gradient of 140 T/m. The resulting conductor peak field of more than 12 T requires the use of Nb3Sn superconducting coils. In this paper the coil design for the quadrupole short model (SQXF) is described, focusing in particular on the optimization of the end-parts. We first describe the magnetic optimization aiming at reducing the peak field enhancement in the ends and minimizing the integrated multipole content. Then we focus on the analysis and tests performed to determine the most suitable shapes of end turns and spacers, minimizing the mechanical stress on the cables. We conclude with a detailed description of the baseline end design for the first series of the short model coils.