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Sample records for 132sn quadrupole collectivity

  1. First evidence of γ collectivity close to the doubly magic core 132Sn

    NASA Astrophysics Data System (ADS)

    Urban, W.; Sieja, K.; RzÄ ca-Urban, T.; Czerwiński, M.; Naïdja, H.; Nowacki, F.; Smith, A. G.; Ahmad, I.

    2016-03-01

    The 138Te and 140Xe nuclei have been reinvestigated using prompt γ -ray data from spontaneous fission of 248Cm, collected with the EUROGAM2 Ge array. γ bands have been identified in both nuclei. The γ band observed in 138Te, a nucleus with only six valence nucleons, indicates the presence of collectivity very close to the doubly magic 132Sn core. Such band is even more pronounced in 140Xe, the N = 86 isotone of 138Te. The newly observed bands are interpreted within the shell model, which reproduce well the γ collectivity at N = 86.

  2. Shell-model investigation of spectroscopic properties and collectivity in the nuclei beyond 132Sn

    NASA Astrophysics Data System (ADS)

    Naïdja, H.; Nowacki, F.; Bounthong, B.

    2017-09-01

    The recent shell-model results of even-even chains of nuclei: 134,136,138Te, 136,138,140Xe, 138,140,142Ba, 140,142,144Ce, and 142,144,146Nd are explored in this manuscript. The low-lying states energies, E2 and M1 transitions, are investigated using the s a m e effective interaction based on the realistic effective field theory potential N3LO. Significant quadrupole correlations appear in the N =86 isotonic chain, with the signature of nonaxial γ band . This class of collectivity is interpreted within the SU(3) symmetries scheme and confirmed by constrained Hartree-Fock shell-model calculations.

  3. Electromagnetic Moments of Radioactive 136Te and the Emergence of Collectivity 2p ⊕ 2n outside of Double-Magic 132Sn

    DOE PAGES

    Allmond, James M; Stuchberry, A. E.; Danchev, M.; ...

    2017-03-03

    Radioactive 136Te has two valence protons and two valence neutrons outside of the 132Sn double shell closure, providing a simple laboratory for exploring the emergence of collectivity and nucleon- nucleon interactions. Coulomb excitation of 136Te on a titanium target was utilized to determine an extensive set of electromagnetic moments for the three lowest-lying states, including B(E2;0more » $$+\\atop{1}$$→ 2$$+\\atop{1}$$ ), Q(2$$+\\atop{1}$$ ), and g(2$$+\\atop{1}$$ ). The results indicate that the first-excited state, 2$$+\\atop{1}$$ , composed of the simple 2p ⊕ 2n system, is prolate deformed, and its wave function is dominated by neutron degrees of freedom, but not to the extent previously suggested. It is demonstrated that extreme sensitivity of g(2$$+\\atop{1}$$) to the proton and neutron contributions to the wave function provides unique insight into the nature of emerging collectivity, and g(2$$+\\atop{1}$$ ) was used to differentiate among several state-of-the-art theoretical calculations. Finally, our results are best described by the most recent shell model calculations.« less

  4. Electromagnetic Moments of Radioactive ^{136}Te and the Emergence of Collectivity 2p⊕2n Outside of Double-Magic ^{132}Sn.

    PubMed

    Allmond, J M; Stuchbery, A E; Baktash, C; Gargano, A; Galindo-Uribarri, A; Radford, D C; Bingham, C R; Brown, B A; Coraggio, L; Covello, A; Danchev, M; Gross, C J; Hausladen, P A; Itaco, N; Lagergren, K; Padilla-Rodal, E; Pavan, J; Riley, M A; Stone, N J; Stracener, D W; Varner, R L; Yu, C-H

    2017-03-03

    Radioactive ^{136}Te has two valence protons and two valence neutrons outside of the ^{132}Sn double shell closure, providing a simple laboratory for exploring the emergence of collectivity and nucleon-nucleon interactions. Coulomb excitation of ^{136}Te on a titanium target was utilized to determine an extensive set of electromagnetic moments for the three lowest-lying states, including B(E2;0_{1}^{+}→2_{1}^{+}), Q(2_{1}^{+}), and g(2_{1}^{+}). The results indicate that the first-excited state, 2_{1}^{+}, composed of the simple 2p⊕2n system, is prolate deformed, and its wave function is dominated by excited valence neutron configurations, but not to the extent previously suggested. It is demonstrated that extreme sensitivity of g(2_{1}^{+}) to the proton and neutron contributions to the wave function provides unique insight into the nature of emerging collectivity, and g(2_{1}^{+}) was used to differentiate among several state-of-the-art theoretical calculations. Our results are best described by the most recent shell model calculations.

  5. Electromagnetic Moments of Radioactive 136Te and the Emergence of Collectivity 2p+2n outside of Double-Magic 132Sn

    SciTech Connect

    Allmond, James M; Stuchberry, A. E.; Danchev, M.; Baktash, Cyrus; Gargano, A.; Galindo-Uribarri, Alfredo {nmn}; Radford, David C; Bingham, C. R.; Brown, Alex; Coraggio, L.; Covello, A.; Gross, Carl J; Hausladen, Paul; Itaco, N.; Lagergren, Karin B; Padilla-Rodal, Elizabeth; Pavan, John R; Riley, Mark; Stone, N. J.; Stracener, Daniel W; Varner Jr, Robert L; Yu, Chang-Hong

    2017-01-01

    Radioactive 136Te has two valence protons and two valence neutrons outside of the 132Sn double shell closure, providing a simple laboratory for exploring the emergence of collectivity and nucleon- nucleon interactions. Coulomb excitation of 136Te on a titanium target was utilized to determine an extensive set of electromagnetic moments for the three lowest-lying states, including B(E2;0+1 2+1 ), Q(2+1 ), and g(2+1 ). The results indicate that the first-excited state, 2+1 , composed of the simple 2p 2n system, is prolate deformed, and its wavefunction is dominated by neutron degrees of freedom, but not to the extent previously suggested. It is demonstrated that extreme sensitivity of g(2+1 ) to the proton and neutron contributions to the wavefunction provides unique insight into the nature of emerging collectivity, and g(2+1 ) was used to differentiate among several state-of-the-art theoretical calculations. Our results are best described by the most recent shell model calculations.

  6. 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.

  7. Structure of even-even A=138 isobars and the yrast spectra of semi-magic Sn isotopes above the {sup 132}Sn core

    SciTech Connect

    Sarkar, S.; Sarkar, M. Saha

    2008-08-15

    Large basis untruncated shell model (SM) calculations have been done for the A=138 neutron-rich nuclei in the {pi}(gdsh)+{nu}(hfpi) valence space above the {sup 132}Sn core using two (1+2) -body nuclear Hamiltonians, viz., realistic CWG and empirical SMPN. Calculated binding energies, excitation spectra, and wave function structures are compared for even-even A=138 isobars for which experimental data are available. The nearly vibrational states in {sup 138}Te, Xe, and the B(E2;2{sup +}{yields}0{sup +}) value in {sup 138}Xe are excellently reproduced by both the interactions. For {sup 138}Ba, the calculated spectra and the B(E2;2{sup +}{yields}0{sup +}) value also agree very well with the experimental results. But the two theoretical results differ dramatically for {sup 138}Sn, a nucleus on the r-process path. CWG predicts nearly constant energies of 2{sub 1}{sup +} states for the even-even Sn isotopes above the {sup 132}Sn core, normally expected for semi-magic nuclei. But SMPN predicts a remarkable new feature: decreasing E(2{sub 1}{sup +}) energies with increasing neutron number. The predicted energies for the Sn isotopes fit in the systematics for the E(2{sub 1}{sup +}) energies of their isotones with Z>50. Despite their differences, both interactions predict the 6{sub 1}{sup +} state to be a {approx_equal}0.3 {mu}s isomer in {sup 138}Sn. Calculated magnetic dipole moments and electric quadrupole moments of the states in these isobars are compared with the experimental data wherever available. The appearance of deformation and evolution of collectivity in nuclei in this valence space are discussed.

  8. Gyromagnetic ratios of excited states and nuclear structure near {sup 132}Sn

    SciTech Connect

    Stuchbery, Andrew E.

    2014-11-11

    Several g-factor measurements have been performed recently on nuclei near the neutron-rich, double-magic nucleus {sup 132}Sn. The focus here is on {sup 134}Te, the N = 82 isotone which has two protons added to {sup 132}Sn. The electromagnetic properties of {sup 134}Te are examined. Comparisons are made with other nuclei that have two protons outside a double-magic core. The extent to which {sup 132}Sn is an inert core is discussed based on these comparisons. The electromagnetic properties of the N = 82 isotones from {sup 132}Sn to {sup 146}Gd are also discussed.

  9. Electromagnetic properties of the 2+ state in 134Te: Influence of core excitation on single-particle orbits beyond 132Sn

    SciTech Connect

    Stuchbery, Andrew E; Allmond, James M; Galindo-Uribarri, Alfredo {nmn}; Padilla-Rodal, Elizabeth; Radford, David C; Stone, N. J.; Batchelder, J. C.; Beene, James R; Benczer-Koller, N.; Bingham, C. R.; Howard, Meredith E; Kumbartzki, G.; Liang, J Felix; Manning, Brett M; Stracener, Daniel W; Yu, Chang-Hong

    2013-01-01

    The g factor and B (E2) of the first excited 2+ state have been measured following Coulomb excitation ofthe neutron-rich semimagic nuclide 134Te (two protons outside 132Sn) produced as a radioactive beam. The precision achieved matches related g-factor measurements on stable beams and distinguishes between alternative models. The B(E2) measurement exposes quadrupole strength in the 2+ state beyond that predicted by current large-basis shell-model calculations. This additional quadrupole strength can be attributed to coupling between the two valence protons and excitations of the 132Sn core. However, the wave functions of the low-excitation positive-parity states in 134Te up to 6+ remain dominated by the (g7/2)2 configuration.

  10. Consistent quadrupole-octupole collective model

    NASA Astrophysics Data System (ADS)

    Dobrowolski, A.; Mazurek, K.; Góźdź, A.

    2016-11-01

    Within this work we present a consistent approach to quadrupole-octupole collective vibrations coupled with the rotational motion. A realistic collective Hamiltonian with variable mass-parameter tensor and potential obtained through the macroscopic-microscopic Strutinsky-like method with particle-number-projected BCS (Bardeen-Cooper-Schrieffer) approach in full vibrational and rotational, nine-dimensional collective space is diagonalized in the basis of projected harmonic oscillator eigensolutions. This orthogonal basis of zero-, one-, two-, and three-phonon oscillator-like functions in vibrational part, coupled with the corresponding Wigner function is, in addition, symmetrized with respect to the so-called symmetrization group, appropriate to the collective space of the model. In the present model it is D4 group acting in the body-fixed frame. This symmetrization procedure is applied in order to provide the uniqueness of the Hamiltonian eigensolutions with respect to the laboratory coordinate system. The symmetrization is obtained using the projection onto the irreducible representation technique. The model generates the quadrupole ground-state spectrum as well as the lowest negative-parity spectrum in 156Gd nucleus. The interband and intraband B (E 1 ) and B (E 2 ) reduced transition probabilities are also calculated within those bands and compared with the recent experimental results for this nucleus. Such a collective approach is helpful in searching for the fingerprints of the possible high-rank symmetries (e.g., octahedral and tetrahedral) in nuclear collective bands.

  11. On transition strengths of E1, E2, & E3 in the regions of mixed quadrupole-octupole collectivity

    NASA Astrophysics Data System (ADS)

    Rasmussen, John; Luo, Y. X.; Hamilton, Joseph; Ramayya, A. V.; Donangelo, Raul

    2010-11-01

    We review the main highlights of experiment and theory for the lowest three electric multipolarities, B(E1), B(E2), and B(E3), for nuclei where quadrupole and octupole collectivity may both occur. The principal regions of interest are around 6 to 12 protons and 6 to 12 neutrons beyond the doubly-closed shell nuclei ^132Sn and ^208Pb. We examine microscopic theoretical calculationsootnotetextW. Zhang et al., Phys. Rev. C 81, 034302 (2010) and references therein. in which deformations are driven by Nilsson orbitals near the Fermi energy. We also focus attention on recent experimentalootnotetextP.E. Garrett et al., Phys. Rev. Letts. 103, 062501 (2009) studies of ^152Sm, where the ground band and associated K=1^- band are mirrored by another 0^+ and 1^- band about 0.7 MeV higher in energy. We suggest that a monopole pairing force alone is insufficient to cause this mirroring, and monopole-plus-quadrupole pairing or a more realistic nucleon-nucleon force is needed.

  12. Dipole Excitation of Soft and Giant Resonances in 132Sn and neighboring unstable nuclei

    NASA Astrophysics Data System (ADS)

    Boretzky, Konstanze

    2006-04-01

    The evolution of dipole-strength distributions above the one-neutron threshold was investigated for exotic neutron-rich nuclei in a series of experiments using the electromagnetic projectile excitation at beam energies around 500 MeV/u. For halo nuclei, the large observed dipole strength (shown here for 11Be) is explained within the direct-breakup model to be of non-collective character. For neutron-rich oxygen isotopes, the origin of the observed low-lying strength is concluded to be due to single-particle transitions on theoretical grounds. The dipole strength spectra for 130,132Sn exhibit resonance-like structures observed at energies around 10 MeV exhausting a few percent of the Thomas-Reiche-Kuhn (TRK) sum rule, separated clearly from the dominant Giant Dipole Resonance (GDR). The data agree with predictions for a new dipole mode related to the oscillation of excess neutrons versus the core nucleons ("pygmy resonance").

  13. Direct reaction measurements with a (132)Sn radioactive ion beam

    SciTech Connect

    Jones, K. L.; Chae, K. Y.; Kapler, R.; Ma, Zhanwen; Moazen, Brian; Cizewski, J. A.; Hatarik, Robert; Pain, S. D.; Swan, T. P.; Nunes, F. M.; Adekola, Aderemi S; Bardayan, Daniel W; Blackmon, Jeff C; Chae, Kyung Yuk; Liang, J Felix; Nesaraja, Caroline D; Pain, Steven D; Shapira, Dan; Smith, Michael Scott; Chipps, Kelly A; Erikson, Luke; Livesay, R. J.; Harlin, Christopher W; Patterson, N. P.; Thomas, J. S.; Kozub, R. L.; Shriner, Jr., John F

    2011-01-01

    The (d,p) neutron transfer and (d,d) elastic scattering reactions were measured in inverse kinematics using a radioactive ion beam of {sup 132}Sn at 630 MeV. The elastic scattering data were taken in a region where Rutherford scattering dominated the reaction, and nuclear effects account for less than 8% of the elastic scattering cross section. The magnitude of the nuclear effects, in the angular range studied, was found to be independent of the optical potential used, allowing the transfer data to be normalized in a reliable manner. The neutron-transfer reaction populated a previously unmeasured state at 1363 keV, which is most likely the single-particle 3p{sub 1/2} state expected above the N=82 shell closure. The data were analyzed using finite-range adiabatic-wave calculations and the results compared with the previous analysis using the distorted-wave Born approximation. Angular distributions for the ground and first-excited states are consistent with the previous tentative spin and parity assignments. Spectroscopic factors extracted from the differential cross sections are similar to those found for the one-neutron states beyond the benchmark doubly magic nucleus {sup 208}Pb.

  14. Direct reaction measurements with a 132Sn radioactive ion beam

    SciTech Connect

    Jones, Katherine L.; Nunes, Filomena M.; Adekola, Aderemi S.; Bardayan, Dan W.; Blackmon, Jeff; Chae, K. Y.; Chipps, Kelly A.; Cizewski, Jolie A.; Erikson, Luke E.; Harlin, C.; Hatarik, R.; Kapler, R.; Kozub, Raymond L.; Liang, J. F.; Livesay, Ronald J.; Ma, Zhongguo J.; Moazen, B. H.; Nesaraja, Caroline D.; Pain, Steven D.; Patterson, N. P.; Shapira, Dan; Shriner, Jr., John F.; Smith, Michael S.; Swan, Thomas P.; Thomas, Jeff S.

    2011-09-01

    The (d,p) neutron transfer and (d,d) elastic scattering reactions were measured in inverse kinematics using a radioactive ion beam of 132Sn at 630 MeV. The elastic scattering data were taken in a region where Rutherford scattering dominated the reaction, and nuclear effects account for less than 8% of the elastic scattering cross section. The magnitude of the nuclear effects, in the angular range studied, was found to be independent of the optical potential used, allowing the transfer data to be normalized in a reliable manner. The neutron-transfer reaction populated a previously unmeasured state at 1363 keV, which is most likely the single-particle 3p1/2 state expected above the N = 82 shell closure. The data were analyzed using finite-range adiabatic-wave calculations and the results compared with the previous analysis using the distorted-wave Born approximation. Angular distributions for the ground and first-excited states are consistent with the previous tentative spin and parity assignments. Spectroscopic factors extracted from the differential cross sections are similar to those found for the one-neutron states beyond the benchmark doubly magic nucleus 208Pb.

  15. TOPICAL REVIEW: Quadrupole collective states within the Bohr collective Hamiltonian

    NASA Astrophysics Data System (ADS)

    Próchniak, L.; Rohoziński, S. G.

    2009-12-01

    The article reviews the general version of the Bohr collective model for the description of quadrupole collective states, including a detailed discussion of the model's kinematics. The quadrupole coordinates, momenta and angular momenta are defined and the structure of the isotropic tensor fields as functions of the tensor variables is investigated. After a comprehensive discussion of the quadrupole kinematics, the general form of the classical and quantum Bohr Hamiltonian is presented. The electric and magnetic multipole moment operators acting in the collective space are constructed and the collective sum rules are given. A discussion of the tensor structure of the collective wavefunctions and a review of various methods of solving the Bohr Hamiltonian eigenvalue equation are also presented. Next, the methods of derivation of the classical and quantum Bohr Hamiltonian from the microscopic many-body theory are recalled. Finally, the microscopic approach to the Bohr Hamiltonian is applied to interpret collective properties of 12 heavy even-even nuclei in the Hf-Hg region. Calculated energy levels and E2 transition probabilities are compared with experimental data.

  16. Few-valence-particle excitations around doubly magic {sup 132}Sn

    SciTech Connect

    Daly, P.J.; Zhang, C.T.; Bhattacharyya, P.

    1996-11-01

    Prompt {gamma}-ray cascades in neutron-rich nuclei around doubly-magic {sup 132}Sn have been studied using a {sup 248}Cm fission source. Yrast states located in the N = 82 isotones {sup 134}Te and {sup 135}I are interpreted as valence proton and neutron particle-hole core excitations with the help of shell model calculations employing empirical nucleon-nucleon interactions from both {sup 132}Sn and {sup 208}Pb regions.

  17. Nuclear Structure Studies in the 132Sn Region: “Safe Coulex” with Carbon Targets

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Stuchbery, A. E.; Galindo-Uribarri, A.; Padilla-Rodal, E.; Radford, D. C.; Batchelder, J. C.; Bingham, C. R.; Howard, M. E.; Liang, J. F.; Manning, B.; Pain, S. D.; Stone, N. J.; Varner, R. L.; Yu, C.-H.

    2015-09-01

    The collective and single-particle structure of nuclei in the 132Sn region was recently studied by Coulomb excitation and heavy-ion induced transfer reactions using carbon, beryllium, and titanium targets. In particular, Coulomb excitation was used determine a complete set of electromagnetic moments for the first 2+ states and one-neutron transfer was used to probe the purity and evolution of single-neutron states. These recent experiments were conducted at the Holifield Radioactive Ion Beam Facility at ORNL using a Csl-HPGe detector array (BareBall- CLARION) to detect scattered particles and emitted gamma rays from the in-beam reactions. A Bragg-curve detector was used to measure the energy loss of the various beams through the targets and to measure the radioactive beam compositions. A sample of the Coulomb excitation results is presented here with an emphasis placed on 116Sn. In particular, the “safe Coulex” criterion for carbon targets will be analyzed and discussed.

  18. Origin of low-energy quadrupole collectivity in vibrational nuclei.

    PubMed

    Walz, C; Fujita, H; Krugmann, A; von Neumann-Cosel, P; Pietralla, N; Ponomarev, V Yu; Scheikh-Obeid, A; Wambach, J

    2011-02-11

    The coupling of the giant quadrupole resonance to valence-space configurations is shown to be the origin of the formation of low-lying quadrupole-collective structures in vibrational nuclei with symmetric and mixed-symmetric character with respect to the proton-neutron degree of freedom. For the first time experimental evidence for this picture is obtained from electron- and proton scattering experiments on the nucleus ^{92}Zr that are sensitive to the relative phase of valence-space amplitudes by quantum interference.

  19. Study of neutron-rich nuclei near doubly magic 132Sn

    NASA Astrophysics Data System (ADS)

    Sarkar, M. Saha; Sarkar, S.

    2012-06-01

    Large basis untruncated shell-model (SM) calculations have been done for nuclei with 50 ≤Z ≤56 and 82 ≤ N ≤ 88 in the π(gdsh) ⊗ ν (hf pi) valence space above the 132Sn core using both realistic CWG and empirical SMPN (1+2)-body Hamiltonians. These neutronrich nuclei lie on or close to the path of astrophysical r-process flow. Reasons behind the similarity and dissimilarity between the results using these two interactions have been discussed. The observation and prediction of unusually depressed first excited 2+1 states in even-A semi-magic Sn isotopes having N =84-88 and the possibility of a new magic number at N = 90 above 132Sn provide motivations for reviewing the problems related to the nuclear astrophysics in general.

  20. The single-particle structure around ^132Sn explored through the (d,p) reaction

    NASA Astrophysics Data System (ADS)

    Jones, Kate

    2007-04-01

    The nuclear shell model^1, originally developed by Maria Geoppert Mayer in 1949 (Nobel Prize 1963) has been used extensively to explain the structure of nuclei. The atomic shell model describes the increased stability observed when an electron shell is filled. Correspondingly, nuclei with magic numbers of protons or neutrons (2, 8, 20, 28, 50, 82, 126) display additional stability. Only ten nuclei to date have been observed which have these standard magic numbers for both neutrons and protons, of these, half are stable or very long-lived. Many changes have been observed in nuclei as we move away from the valley of stability and it is important, both to nuclear structure physics and to understanding the synthesis of nuclei in the cosmos, to understand how these changes affect single-particle states.One exotic doubly-magic nucleus which can be produced with sufficient intensity to perform reactions on it is ^132Sn. Recent calculations^2 have shown that the structure around ^132Sn may affect the freeze out of the rapid neutron capture (r-)process, believed to occur in supernovae, which is responsible for the production of about half the nuclear species heavier than iron. By adding a neutron to a beam of ^132Sn via a transfer reaction, it is possible to study single-particle states beyond the double-shell closure. I will present results from a recent measurement of ^133Sn via the ^132Sn(d,p) reaction in inverse kinematics. [1] Maria Goeppert Mayer, Science 145 999 (1964). [2] R. Surman and J. Engel, Phys. Rev. C 64, 035801 (2001).

  1. Studies of Nuclei Close to 132Sn Using Single-Neutron Transfer Reactions

    SciTech Connect

    Jones, K. L.; Pain, S. D.; Kozub, R. L.; Adekola, Aderemi S; Bardayan, Daniel W; Blackmon, Jeff C; Catford, Wilton N; Chae, K. Y.; Chipps, K.; Cizewski, J. A.; Erikson, Luke; Gaddis, A. L.; Greife, U.; Grzywacz, R. K.; Harlin, Christopher W; Hatarik, Robert; Howard, Joshua A; James, J.; Kapler, R.; Krolas, W.; Liang, J Felix; Ma, Zhanwen; Matei, Catalin; Moazen, Brian; Nesaraja, Caroline D; O'Malley, Patrick; Patterson, N. P.; Paulauskas, Stanley; Shapira, Dan; ShrinerJr., J. F.; Sikora, M.; Sissom, D. J.; Smith, Michael Scott; Swan, T. P.; Thomas, J. S.; Wilson, Gemma L

    2009-01-01

    Neutron transfer reactions were performed in inverse kinematics using radioactive ion beams of 132Sn, 130Sn, and 134Te and deuterated polyethylene targets. Preliminary results are presented. The Q-value spectra for 133Sn, 131Sn and 135Te reveal a number of previously unobserved peaks. The angular distributions are compatible with the expected lf7/2 nature of the ground state of 133Sn, and 2p3/2 for the 3.4 MeV state in 131Sn.

  2. Studies of nuclei close to {sup 132}Sn using single-neutron transfer reactions

    SciTech Connect

    Jones, K. J.; Pain, S. D.; Kozub, R. L.; Howard, J. A.; O'Malley, P. D.; Paulauskas, S. V.; Shriner, J. F.; Sissom, D. J.; Adekola, A. S.; Bardayan, D. W.; Blackmon, J. C.; Liang, J. F.; Nesaraja, C. D.; Shapira, D.; Smith, M. S.; Catford, W. N.; Harlin, C.; Patterson, N. P.; Swan, T. P.; Wilson, G. L.

    2009-03-04

    Neutron transfer reactions were performed in inverse kinematics using radioactive ion beams of {sup 132}Sn, {sup 130}Sn, and {sup 134}Te and deuterated polyethylene targets. Preliminary results are presented. The Q-value spectra for {sup 133}Sn, {sup 131}Sn and {sup 135}Te reveal a number of previously unobserved peaks. The angular distributions are compatible with the expected lf{sub 7/2} nature of the ground state of {sup 133}Sn, and 2p{sub 3/2} for the 3.4 MeV state in {sup 131}Sn.

  3. The magic nature of 132Sn explored through the single-particle states of 133Sn

    SciTech Connect

    Jones, K. L.; Adekola, Aderemi S; Bardayan, Daniel W; Blackmon, Jeff C; Chae, K. Y.; Chipps, K.; Cizewski, J. A.; Erikson, Luke; Harlin, Christopher W; Hatarik, Robert; Kapler, R.; Kozub, R. L.; Liang, J Felix; Livesay, Jake; Ma, Zhanwen; Moazen, Brian; Nesaraja, Caroline D; Nunes, F. M.; Pain, S. D.; Patterson, N. P.; Shapira, Dan; ShrinerJr., J. F.; Smith, Michael Scott; Swan, T. P.; Thomas, J. S.

    2010-05-01

    Atomic nuclei have a shell structure1 in which nuclei with magic numbers of neutrons and protons are analogous to the noble gases in atomic physics. Only ten nuclei with the standard magic numbers of both neutrons and protons have so far been observed. The nuclear shell model is founded on the precept that neutrons and protons can move as independent particles in orbitals with discrete quantum numbers, subject to a mean field generated by all the other nucleons. Knowledge of the properties of single-particle states outside nuclear shell closures in exotic nuclei is important2 5 for a fundamental understanding of nuclear structure and nucleosynthesis (for example the r-process, which is responsible for the production of about half of the heavy elements). However, as a result of their short lifetimes, there is a paucity of knowledge about the nature of single-particle states outside exotic doubly magic nuclei. Here we measure the single-particle character of the levels in 133Sn that lies outside the double shell closure present at the short-lived nucleus 132Sn. We use an inverse kinematics technique that involves the transfer of a single nucleon to the nucleus. The purity of the measured single-particle states clearly illustrates the magic nature of 132Sn.

  4. 1p3/2 proton-hole state in 132Sn and the shell structure along N = 82.

    PubMed

    Taprogge, J; Jungclaus, A; Grawe, H; Nishimura, S; Doornenbal, P; Lorusso, G; Simpson, G S; Söderström, P-A; Sumikama, T; Xu, Z Y; Baba, H; Browne, F; Fukuda, N; Gernhäuser, R; Gey, G; Inabe, N; Isobe, T; Jung, H S; Kameda, D; Kim, G D; Kim, Y-K; Kojouharov, I; Kubo, T; Kurz, N; Kwon, Y K; Li, Z; Sakurai, H; Schaffner, H; Steiger, K; Suzuki, H; Takeda, H; Vajta, Zs; Watanabe, H; Wu, J; Yagi, A; Yoshinaga, K; Benzoni, G; Bönig, S; Chae, K Y; Coraggio, L; Covello, A; Daugas, J-M; Drouet, F; Gadea, A; Gargano, A; Ilieva, S; Kondev, F G; Kröll, T; Lane, G J; Montaner-Pizá, A; Moschner, K; Mücher, D; Naqvi, F; Niikura, M; Nishibata, H; Odahara, A; Orlandi, R; Patel, Z; Podolyák, Zs; Wendt, A

    2014-04-04

    A low-lying state in 131In82, the one-proton hole nucleus with respect to double magic 132Sn, was observed by its γ decay to the Iπ=1/2- β-emitting isomer. We identify the new state at an excitation energy of Ex=1353  keV, which was populated both in the β decay of 131Cd83 and after β-delayed neutron emission from 132Cd84, as the previously unknown πp3/2 single-hole state with respect to the 132Sn core. Exploiting this crucial new experimental information, shell-model calculations were performed to study the structure of experimentally inaccessible N=82 isotones below 132Sn. The results evidence a surprising absence of proton subshell closures along the chain of N=82 isotones. The consequences of this finding for the evolution of the N=82 shell gap along the r-process path are discussed.

  5. Realistic shell-model calculations and exotic nuclei around {sup 132}Sn

    SciTech Connect

    Covello, A.; Itaco, N.; Coraggio, L.; Gargano, A.

    2008-11-11

    We report on a study of exotic nuclei around doubly magic {sup 132}Sn in terms of the shell model employing a realistic effective interaction derived from the CD-Bonn nucleon-nucleon potential. The short-range repulsion of the latter is renormalized by constructing a smooth low-momentum potential, V{sub low-k}, that is used directly as input for the calculation of the effective interaction. In this paper, we focus attention on proton-neutron multiplets in the odd-odd nuclei {sup 134}Sb, {sup 136}Sb. We show that the behavior of these multiplets is quite similar to that of the analogous multiplets in the counterpart nuclei in the {sup 208}Pb region, {sup 210}Bi and {sup 212}Bi.

  6. 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.

  7. Quadrupole Collectivity in Neutron-Rich Fe and Cr Isotopes

    NASA Astrophysics Data System (ADS)

    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.

    2013-06-01

    Intermediate-energy Coulomb excitation measurements are performed on the N≥40 neutron-rich nuclei Fe66,68 and Cr64. The reduced transition matrix elements providing a direct measure of the quadrupole collectivity B(E2;21+→01+) are determined for the first time in Fe4268 and Cr4064 and confirm a previous recoil distance method lifetime measurement in Fe4066. 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.

  8. Precise Coulomb excitation B(E2) measurements for first 2+states of projectile nuclei near the doubly magic nuclei 78Ni and 132Sn

    NASA Astrophysics Data System (ADS)

    Galindo-Uribarri, A.

    2012-09-01

    Coulomb excitation is a very precise tool to measure excitation probabilities and provide insight on the collectivity of nuclear excitations and in particular on nuclear shapes. In the last few years radioactive ion beam facilities such as HRIBF opened unique opportunities to explore the structure of nuclei in the regions near the doubly magic nuclei 78Ni (Z=28 and N=50) and 132Sn (Z=50 and N=82). For this purpose we have developed specialized methods and instrumentation to measure various observables. There is also the opportunity to perform precision experiments with stable beams using exactly the same state-of-the-art instrumentation and techniques as with their radioactive ion beam counterpart. I describe some of the recent efforts at HRIBF to do more precise measurements using particle-gamma techniques.

  9. Effects of the symmetry energy in the 132Sn+124Sn reaction at 300 MeV/nucleon

    NASA Astrophysics Data System (ADS)

    Cheng, Shan-Jing; Yong, Gao-Chan; Wen, De-Hua

    2016-12-01

    Based on the recently updated isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model, we studied the effects of symmetry energy on the neutron to proton ratio n /p and the π-/π+ ratio in the central 132Sn+124Sn reaction at 300 MeV/nucleon. It is found that the n /p ratio and the π-/π+ ratio in the central 132Sn+124Sn reaction at 300 MeV/nucleon mainly probe the symmetry energy in the density region 1-1.5 times saturation density. However, the π-/π+ ratio may be able to probe the density-dependent symmetry energy above 1.5 times saturation density by making some kinematic restrictions such as the azimuthal angle and kinetic energy cuts of emitting pions.

  10. Neutron hole states in 131Sn studied via the 132Sn(d,t)131Sn reaction

    NASA Astrophysics Data System (ADS)

    Orlandi, Riccardo; Pain, S. D.; Bardayan, D. W.; Gross, C. J.; Smith, M. S.; Jungclaus, A.; Ahn, S.; Jones, K. L.; Pittman, S. T.; Schmitt, K. T.; Chipps, K. A.; Cizewski, J. A.; Howard, M.; Manning, B.; O'Malley, P. D.; Ratkiewicz, A.; Peters, W. A.; Matos, M.; Chapman, R.; Smith, J. F.; Catford, W.; Shand, C.

    2014-09-01

    Knowledge of single-particle energies in the vicinity of exotic doubly-magic nuclei is of critical importance to understand evolution of nuclear structure. In the present work, the 132Sn(d,t)131Sn reaction (Q = -1.055 MeV) was studied in inverse kinematics at HRIBF of Oak Ridge National Laboratory. The 132Sn ISOL beam was post-accelerated to an energy of 4.39 MeV/u using the ORNL HRIBF accelerator. The beam (average intensity of ~1.2e4 pps) impinged on a ~250- μg/cm2 deuterated polyethylene target, for approximately 4 days. Ejected tritons were detected using the Super ORRUBA array of segmented Si telescopes. Low-lying states in 131Sn were populated in the experiment. Preliminary results will be shown. Work supported by the Spanish project MEC Consolider 2010, the US Department of Energy and the National Science Foundation.

  11. Recent approaches to quadrupole collectivity: models, solutions and applications based on the Bohr hamiltonian

    NASA Astrophysics Data System (ADS)

    Buganu, Petricǎ; Fortunato, Lorenzo

    2016-09-01

    We review and discuss several recent approaches to quadrupole collectivity and developments of collective models and their solutions with many applications, examples and references. We focus in particular on analytic and approximate solutions of the Bohr hamiltonian of the last decade, because most of the previously published material has been already reviewed in other publications.

  12. Nuclear collective motion with a coherent coupling interaction between quadrupole and octupole modes

    NASA Astrophysics Data System (ADS)

    Minkov, N.; Yotov, P.; Drenska, S.; Scheid, W.; Bonatsos, D.; Lenis, D.; Petrellis, D.

    2006-04-01

    A collective Hamiltonian for the rotation-vibration motion of nuclei is considered in which the axial quadrupole and octupole degrees of freedom are coupled through the centrifugal interaction. The potential of the system depends on the two deformation variables β2 and β3. The system is considered to oscillate between positive and negative β3 values by rounding an infinite potential core in the (β2,β3) plane with β2>0. By assuming a coherent contribution of the quadrupole and octupole oscillation modes in the collective motion, the energy spectrum is derived in an explicit analytic form, providing specific parity shift effects. On this basis several possible ways in the evolution of quadrupole-octupole collectivity are outlined. A particular application of the model to the energy levels and electric transition probabilities in alternating parity spectra of the nuclei Nd150, Sm152, Gd154, and Dy156 is presented.

  13. Double-magic nature of 132Sn and 208Pb through lifetime and cross-section measurements.

    PubMed

    Allmond, J M; Stuchbery, A E; Beene, J R; Galindo-Uribarri, A; Liang, J F; Padilla-Rodal, E; Radford, D C; Varner, R L; Ayres, A; Batchelder, J C; Bey, A; Bingham, C R; Howard, M E; Jones, K L; Manning, B; Mueller, P E; Nesaraja, C D; Pain, S D; Peters, W A; Ratkiewicz, A; Schmitt, K T; Shapira, D; Smith, M S; Stone, N J; Stracener, D W; Yu, C-H

    2014-05-02

    Single-neutron states in (133)Sn and (209)Pb, which are analogous to single-electron states outside of closed atomic shells in alkali metals, were populated by the ((9)Be, (8)Be) one-neutron transfer reaction in inverse kinematics using particle-γ coincidence spectroscopy. In addition, the s(1/2) single-neutron hole-state candidate in (131)Sn was populated by ((9)Be, (10)Be). Doubly closed-shell (132)Sn (radioactive) and (208)Pb (stable) beams were used at sub-Coulomb barrier energies of 3 MeV per nucleon. Level energies, γ-ray transitions, absolute cross sections, spectroscopic factors, asymptotic normalization coefficients, and excited-state lifetimes are reported and compared with shell-model expectations. The results include a new transition and precise level energy for the 3p(1/2) candidate in (133)Sn, new absolute cross sections for the 1h(9/2) candidate in (133)Sn and 3s(1/2) candidate in (131)Sn, and new lifetimes for excited states in (133)Sn and (209)Pb. This is the first report on excited-state lifetimes of (133)Sn, which allow for a unique test of the nuclear shell model and (132)Sn double-shell closure.

  14. Double-magic nature of 132Sn and 208Pb through lifetime and cross-section measurements

    SciTech Connect

    Allmond, James M; Stuchbery, Andrew E; Beene, James R; Galindo-Uribarri, Alfredo {nmn}; Liang, J Felix; Padilla-Rodal, Elizabeth; Radford, David C; Varner Jr, Robert L; Ayres, A.; Batchelder, J. C.; Bey, A.; Bingham, C. R.; Howard, Meredith E; Jones, K. L.; Manning, Brett M; Mueller, Paul Edward; Nesaraja, Caroline D; Pain, Steven D; Peters, William A; Ratkiewicz, Andrew J; Schmitt, Kyle; Shapira, Dan; Smith, Michael Scott; Stone, N. J.; Stracener, Daniel W; Yu, Chang-Hong

    2014-01-01

    Single-neutron states in 133Sn and 209Pb, which are analogous to single electrons outside of closed atomic shells in alkali metals, were populated by the (9Be,8Be) one-neutron transfer reaction in inverse kinematics using particle-gamma coincidence spectroscopy. In addition, the s1/2 single-neutron hole-state candidate in 131Sn was populated by (9Be,10Be). Doubly closed-shell 132Sn (radioactive) and 208Pb (stable) beams were used at sub-Coulomb barrier energies of 3 MeV per nucleon. Level energies, gamma-ray transitions, absolute cross sections, spectroscopic factors, asymptotic normalization coefficients, and excited-state lifetimes are reported and compared to shell-model expectations. The results include a new transition and precise level energy for the 3p1/2 candidate in 133Sn, new absolute cross sections for the 1h9/2 candidate in 133Sn and 3s1/2 candidate in 131Sn, and new lifetimes for excited states in 133Sn and 209Pb. This is the first report on excited-state lifetimes of 133Sn, which provide a unique signature of the single-neutron states and 132Sn double-shell closure.

  15. Spectroscopy of few-particle nuclei around magic {sup 132}Sn from fission product {gamma}-ray studies.

    SciTech Connect

    Zhang, C. T.

    1998-07-29

    We are studying the yrast structure of very neutron-rich nuclei around doubly magic {sup 132}Sn by analyzing fission product {gamma}-ray data from a {sup 248}Cm source at Eurogam II. Yrast cascades in several few-valence-particle nuclei have been identified through {gamma}{gamma} cross coincidences with their complementary fission partners. Results for two-valence-particle nuclei {sup 132}Sb, {sup 134}Te, {sup 134}Sb and {sup 134}Sn provide empirical nucleon-nucleon interactions which, combined with single-particle energies already known in the one-particle nuclei, are essential for shell-model analysis in this region. Findings for the N = 82 nuclei {sup 134}Te and {sup 135}I have now been extended to the four-proton nucleus {sup 136}Xe. Results for the two-neutron nucleus {sup 134}Sn and the N = 83 isotones {sup 134}Sb, {sup 135}Te and {sup 135}I open up the spectroscopy of nuclei in the northeast quadrant above {sup 132}Sn.

  16. Collective states of odd nuclei in a model with quadrupole-octupole degrees of freedom

    SciTech Connect

    Minkov, N. Drenska, S. B.; Yotov, P.; Bonatsos, D. Scheid, W.

    2007-08-15

    We apply the collective axial quadrupole-octupole Hamiltonian to describe the rotation-vibration motion of odd nuclei with Coriolis coupling between the even-even core and the unpaired nucleon.We consider that the core oscillates coherently with respect to the quadrupole and octupole axialdeformation variables. The coupling between the core and the unpaired nucleon provides a split paritydoublet structure of the spectrum. The formalism successfully reproduces the parity-doublet splitting in a wide range of odd-A nuclei. It provides model estimations for the third angular-momentum projection K on the intrinsic symmetry axis and the related intrinsic nuclear structure.

  17. Similarity of nuclear structure in the {sup 132}Sn and {sup 208}Pb regions: Proton-neutron multiplets

    SciTech Connect

    Coraggio, L.; Gargano, A.; Covello, A.; Itaco, N.

    2009-08-15

    Starting from the striking similarity of proton-neutron multiplets in {sup 134}Sb and {sup 210}Bi, we perform a shell-model study of nuclei with two additional protons or neutrons to find out to what extent this analogy persists. We employ effective interactions derived from the CD-Bonn nucleon-nucleon potential renormalized by use of the V{sub low-k} approach. The calculated results for {sup 136}Sb, {sup 212}Bi, {sup 136}I, and {sup 212}At are in very good agreement with the available experimental data. The similarity between {sup 132}Sn and {sup 208}Pb regions is discussed in connection with the effective interaction, emphasizing the role of core polarization effects.

  18. Evolution of the N = 82 shell gap below 132Sn inferred from core excited states in 131In

    NASA Astrophysics Data System (ADS)

    Górska, M.; Cáceres, L.; Grawe, H.; Pfützner, M.; Jungclaus, A.; Pietri, S.; Werner-Malento, E.; Podolyák, Z.; Regan, P. H.; Rudolph, D.; Detistov, P.; Lalkovski, S.; Modamio, V.; Walker, J.; Beck, T.; Bednarczyk, P.; Doornenbal, P.; Geissel, H.; Gerl, J.; Grȩbosz, J.; Hoischen, R.; Kojouharov, I.; Kurz, N.; Prokopowicz, W.; Schaffner, H.; Weick, H.; Wollersheim, H.-J.; Andgren, K.; Benlliure, J.; Benzoni, G.; Bruce, A. M.; Casarejos, E.; Cederwall, B.; Crespi, F. C. L.; Hadinia, B.; Hellström, M.; Ilie, G.; Khaplanov, A.; Kmiecik, M.; Kumar, R.; Maj, A.; Mandal, S.; Montes, F.; Myalski, S.; Simpson, G. S.; Steer, S. J.; Tashenov, S.; Wieland, O.; Dombrádi, Zs.; Reiter, P.; Sohler, D.

    2009-03-01

    The γ-ray decay of an excited state in 131In, the one proton hole neighbor of the doubly magic 132Sn has been measured. A high-spin, core-excited isomer with T1 / 2 = 630 (60) ns was identified following production by both relativistic fragmentation of a 136Xe beam and fission of a 238U beam. This state deexcites by a single γ-ray branch of 3782(2) keV from which direct evidence for the size of the N = 82 shell gap is inferred. The results are discussed in comparison to a shell-model calculation including configurations across the closed shells at N = 82 and Z = 50.

  19. Studies of quadrupole collectivity in the γ -soft 106Ru

    NASA Astrophysics Data System (ADS)

    Sanchez-Vega, M.; Mach, H.; Taylor, R. B. E.; Fogelberg, B.; Lindroth, A.; Aas, A. J.; Dendooven, P.; Honkanen, A.; Huhta, M.; Lhersonneau, G.; Oinonen, M.; Parmonen, J. M.; Penttilä, H.; Äystö, J.; Persson, J. R.; Kurpeta, J.

    2008-02-01

    Various alternative models were used to describe the structure of 106Ru . For example, the General Collective Model (GCM) predicts shape-coexistence for 106Ru with a spherical and a triaxial minimum and strongly mixed structures, while in the IBA-2 calculations, where 106Ru was considered as transitional from vibrational U(5) to γ -soft O(6) , no need was found to include the shape-coexisting configurations. In order to provide additional constraints on the model interpretations, we have applied the Advanced Time-Delayed (ATD) βγγ( t) method to measure the level lifetimes of the excited levels in 106Ru . The new results include the half-lives of T 1/2 = 183(3) ps and 7.5(30)ps for the 2+ 1 and 2+ 2 states, respectively.

  20. Point dipole and quadrupole scattering approximation to collectively responding resonator systems

    NASA Astrophysics Data System (ADS)

    Watson, Derek W.; Jenkins, Stewart D.; Ruostekoski, Janne

    2017-07-01

    We develop a theoretical formalism for collectively responding point scatterers where the radiating electromagnetic fields from each emitter are considered in the electric dipole, magnetic dipole, and electric quadrupole approximation. The contributions of the electric quadrupole moment to electromagnetically-mediated interactions between the scatterers are derived in detail for a system where each scatterer represents a linear R L C circuit resonator, representing common metamaterial resonators in radiofrequency, microwave, and optical regimes. The resulting theory includes a closed set of equations for an ensemble of discrete resonators that are radiatively coupled to each other by propagating electromagnetic fields, incorporating potentially strong interactions and recurrent scattering processes. The effective model is illustrated and tested for examples of pairs of interacting point electric dipoles, where each pair can be qualitatively replaced by a model point emitter with different multipole radiation moments.

  1. Isomerism in the "south-east" of 132Sn and a predicted neutron-decaying isomer in 129Pd

    NASA Astrophysics Data System (ADS)

    Yuan, Cenxi; Liu, Zhong; Xu, Furong; Walker, P. M.; Podolyák, Zs.; Xu, C.; Ren, Z. Z.; Ding, B.; Liu, M. L.; Liu, X. Y.; Xu, H. S.; Zhang, Y. H.; Zhou, X. H.; Zuo, W.

    2016-11-01

    Excited states in neutron-rich nuclei located south-east of 132Sn are investigated by shell-model calculations. A new shell-model Hamiltonian is constructed for the present study. The proton-proton and neutron-neutron interactions of the Hamiltonian are obtained through the existing CD-Bonn G matrix results, while the proton-neutron interaction across two major shells is derived from the monopole based universal interaction plus the M3Y spin-orbit force. The present Hamiltonian can reproduce well the experimental data available in this region, including one-neutron separation energies, level energies and the experimental B (E 2) values of isomers in 134,136,138Sn, 130Cd, and 128Pd. New isomers are predicted in this region, e.g. in 135Sn, 131Cd, 129Pd, 132,134In and 130Ag, in which almost no excited states are known experimentally yet. In the odd-odd 132,134In and 130Ag, the predicted very long E2 life-times of the low-lying 5- states are discussed, demanding more information on the related proton-neutron interaction. The low-lying states of 132In are discussed in connection with the recently observed γ rays. The predicted 19 /2- isomer in 129Pd could decay by both electromagnetic transitions and neutron emission with comparable partial life-times, making it a good candidate for neutron radioactivity, a decay mode which is yet to be discovered.

  2. Monopole effects, isomeric states, and cross-shell excitations in the A =129 hole nuclei near 132Sn

    NASA Astrophysics Data System (ADS)

    Wang, Han-Kui; Kaneko, Kazunari; Sun, Yang; He, Yi-Qi; Li, Shao-Feng; Li, Jian

    2017-01-01

    We present results of large-scale shell-model calculations for the A =129 hole nuclei below 132Sn. We discuss structures of 129Sn, 129In, and 129Cd with emphasis on the monopole effects and excitations across the neutron N =82 shell gap, and further predict low-lying levels for the more exotic 129Ag. It is demonstrated that the monopole corrections in the Hamiltonian, which dynamically affect occupations of relevant orbits, can lead to interesting consequences for the shell evolution. It is found especially that the monopole terms, previously introduced to reproduce the cross-shell excitations of the 17 /2+ and 21 /2+ states in 131In, shows more pronounced effects on the A =129 nuclei. In 129In, the cross-shell excitations of 17 /2+ and 21 /2+ are pushed down significantly by the monopole terms, and in 129Cd, the same monopole terms reverse the order of the single-hole states of ν d3 /2 and ν h11 /2 , causing 11/2 - as the ground state for this nucleus. The structure of isomeric states in the A =129 nuclei is also discussed.

  3. Quadrupole Collectivity beyond N=28: Intermediate-Energy Coulomb Excitation of Ar47,48

    NASA Astrophysics Data System (ADS)

    Winkler, R.; Gade, A.; Baugher, T.; Bazin, D.; Brown, B. A.; Glasmacher, T.; Grinyer, G. F.; Meharchand, R.; McDaniel, S.; Ratkiewicz, A.; Weisshaar, D.

    2012-05-01

    We report on the first experimental study of quadrupole collectivity in the very neutron-rich nuclei Ar47,48 using intermediate-energy Coulomb excitation. These nuclei are located along the path from doubly magic Ca to collective S and Si isotopes, a critical region of shell evolution and structural change. The deduced B(E2) transition strengths are confronted with large-scale shell-model calculations in the sdpf shell using the state-of-the-art SDPF-Uand EPQQM effective interactions. The comparison between experiment and theory indicates that a shell-model description of Ar isotopes around N=28 remains a challenge.

  4. Quadrupole collectivity beyond N = 28: intermediate-energy Coulomb excitation of (47,48)Ar.

    PubMed

    Winkler, R; Gade, A; Baugher, T; Bazin, D; Brown, B A; Glasmacher, T; Grinyer, G F; Meharchand, R; McDaniel, S; Ratkiewicz, A; Weisshaar, D

    2012-05-04

    We report on the first experimental study of quadrupole collectivity in the very neutron-rich nuclei (47,48)Ar using intermediate-energy Coulomb excitation. These nuclei are located along the path from doubly magic Ca to collective S and Si isotopes, a critical region of shell evolution and structural change. The deduced B(E2) transition strengths are confronted with large-scale shell-model calculations in the sdpf shell using the state-of-the-art SDPF-Uand EPQQM effective interactions. The comparison between experiment and theory indicates that a shell-model description of Ar isotopes around N=28 remains a challenge.

  5. Structure of 52 132Te80: The two-particle and two-hole spectrum of 50 132Sn82

    NASA Astrophysics Data System (ADS)

    Biswas, S.; Palit, R.; Navin, A.; Rejmund, M.; Bisoi, A.; Sarkar, M. Saha; Sarkar, S.; Bhattacharyya, S.; Biswas, D. C.; Caamaño, M.; Carpenter, M. P.; Choudhury, D.; Clément, E.; Danu, L. S.; Delaune, O.; Farget, F.; de France, G.; Hota, S. S.; Jacquot, B.; Lemasson, A.; Mukhopadhyay, S.; Nanal, V.; Pillay, R. G.; Saha, S.; Sethi, J.; Singh, Purnima; Srivastava, P. C.; Tandel, S. K.

    2016-03-01

    High-spin states in 132Te, an isotope with two proton particles and two neutron holes outside of the 132Sn doubly magic core, have been extended up to an excitation energy of 6.17 MeV. The prompt-delayed coincidence technique has been used to correlate states above the T1 /2=3.70 (9 ) μ s isomer in 132Te to the lower states using 232Th(7Li,f ) at 5.4 MeV/u and the Indian National Gamma Array (INGA). With 9Be(238U,f ) at 6.2 MeV/u and EXOGAM γ -array coupled with the VAMOS++ spectrometer, the level scheme was extended to higher excitation energies. The high-spin positive-parity states, above Jπ=10+ , in 132Te are expected to arise from the alignment of the particles in the high-j orbitals lying close to the Fermi surface, the π g7/2 2 , and the ν h11/2 -2 configurations. The experimental level scheme has been compared with the large scale shell model calculations. A reduction in the p -n interaction strength resulted in an improved agreement with the measurements up to the spin of 15 ℏ . In contrast, the comparison of the differences between the experiment and these calculations for the N =76 ,78 isotones of Te and Sn shows the increasing disagreement as a function of spin, where the magnitude is larger in Te than in Sn. This behavior could possibly be attributed to the deficiencies in the p -n correlations, in addition to the n -n correlations in Sn.

  6. Search for one- and two-phonon octupole vibrational states in the spherical nuclei near 132Sn

    NASA Astrophysics Data System (ADS)

    Hwang, J. K.; Hamilton, J. H.; Ramayya, A. V.; Luo, Y. X.

    2013-10-01

    Excited high spin states in 135I, 136Xe, 137Cs, 138Ba, 139La, 140Ce and 142Nd with N = 82 are reorganized and interpreted in a different way to find one- phonon octupole vibrational (POV) bands. Two nearly identical (similar) bands with ΔI = 3 are found in these nuclei. From the presence of two nearly identical excited bands with ΔI = 3 in these nuclei, one-POV bands are proposed. Also, high spin states of 134Sb, 134,135Te, 135,136I, 137Xe and 139Ba near 132Sn are reanalyzed in order to search for one- and two-POV states. New spins and parities are tentatively assigned to the 2203.9 keV state in 137Xe and the 1976.6 and 2091.7 keV states in 139Ba from the state energy plots of the N = 82 and 83 nuclei. High spin states of 134Sb, 134,135Te, 135,136I, 137Xe and 139Ba connected by E1, E3 /M2 and E3 transitions are proposed, for the first time, as zero-, one- and two-POV states. One- and two-POV states in 134Sb and 135Te are built on a 7- (πg7/2 ν f7/2) state and a 19 /2- (νf7/2 ⊗ 61+)state, respectively. One-POV states built on the 19 /2- (ν f7/2 ⊗ 61+)and the 21 /2- (νh9/2 ⊗ 62+)states coexist in 137Xe. Then, one- and two-POV states in 139Ba are built only on the 21 /2- (νh9/2 ⊗ 62+)state. One- and two-POV states in 134Te are built on the 62+state with some mixing with the 61+state.

  7. Yrast excitations around {sup 132}Sn: The two and three valence- proton N = 82 isotones {sup 134}Te and {sup 135}I

    SciTech Connect

    Daly, P.J.; Zhang, C.T.; Bhattacharyya, P.

    1996-11-01

    Large multidetector {gamma}-ray arrays, which can separate the prompt {gamma}-ray cascades within a single fission product nucleus (of moderate yield) from the bulk of prompt {gamma}-rays, has now opened new prospects for studies of yrast excitations in {sup 132}Sn and the few valence particle nuclei around it. Measurements were performed at Eurogam II using a {sup 248}Cm source. This paper features the results for the two and three valence proton N=82 isotones {sup 134}Te and {sup 135}I which exhibit simple clearcut excitation modes, resembling {sup 210}Po and {sup 211}At, their well studied N=126 counterparts in the {sup 208}Pb region. A search was made for new {sup 135}I transitions by setting a single coincidence gate on 1134 keV {gamma}-rays; strong 288, 572, 690, 725, 1661, 1695, and 2247 keV coincident {gamma}-rays were identified as {sup 135}I {gamma}-rays. In summary, yrast excitations to above 5.5 MeV excitation energy in the 2- and 3-proton nuclei {sup 134}Te and {sup 135}I have been established and interpreted with help of shell model calculations using empirical nucleon-nucleon interactions. This opens possibilities for exploring simple excitation modes in the {sup 132}Sn region under conditions comparable with but not identical to those in the well-studied {sup 208}Pb region.

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

    DOE PAGES

    Radich, A. J.; Garrett, P. E.; Allmond, J. M.; ...

    2015-04-01

    The nuclear structure of 124Xe has been investigated via measurements of the β+/EC decay of 124Cs with the 8π γ-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,more » $$B(E2; 2^+_3 → 0^+_2)$$ = 78(13) W.u. and $$B(E2; 2^+_4 → 0^+_3)$$ = 53(12) W.u. were determined. The $$0^+_3$$ 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.« less

  9. Monopole-driven shell evolution below the doubly magic nucleus 132Sn explored with the long-lived isomer in 126Pd.

    PubMed

    Watanabe, H; Lorusso, G; Nishimura, S; Otsuka, T; Ogawa, K; Xu, Z Y; Sumikama, T; Söderström, P-A; Doornenbal, P; Li, Z; Browne, F; Gey, G; Jung, H S; Taprogge, J; Vajta, Zs; Wu, J; Yagi, A; Baba, H; Benzoni, G; Chae, K Y; Crespi, F C L; Fukuda, N; Gernhäuser, R; Inabe, N; Isobe, T; Jungclaus, A; Kameda, D; Kim, G D; Kim, Y K; Kojouharov, I; Kondev, F G; Kubo, T; Kurz, N; Kwon, Y K; Lane, G J; Moon, C-B; Montaner-Pizá, A; Moschner, K; Naqvi, F; Niikura, M; Nishibata, H; Nishimura, D; Odahara, A; Orlandi, R; Patel, Z; Podolyák, Zs; Sakurai, H; Schaffner, H; Simpson, G S; Steiger, K; Suzuki, H; Takeda, H; Wendt, A; Yoshinaga, K

    2014-07-25

    A new isomer with a half-life of 23.0(8) ms has been identified at 2406 keV in (126)Pd and is proposed to have a spin and parity of 10(+) with a maximally aligned configuration comprising two neutron holes in the 1h(11/2) orbit. In addition to an internal-decay branch through a hindered electric octupole transition, β decay from the long-lived isomer was observed to populate excited states at high spins in (126)Ag. The smaller energy difference between the 10(+) and 7(-) isomers in (126)Pd than in the heavier N=80 isotones can be interpreted as being ascribed to the monopole shift of the 1h(11/2) neutron orbit. The effects of the monopole interaction on the evolution of single-neutron energies below (132)Sn are discussed in terms of the central and tensor forces.

  10. Study of Gamow-Teller transitions from 132Sn via the (p,n) reaction at 220 MeV/u in inverse kinematics

    NASA Astrophysics Data System (ADS)

    Sasano, M.; Yasuda, J.; Zegers, R. G. T.; Baba, H.; Chao, W.; Dozono, M.; Fukuda, N.; Inabe, N.; Isobe, T.; Jhang, G.; Kamaeda, D.; Kubo, T.; Kurata-Nishimura, M.; Milman, E.; Motobayashi, T.; Otsu, H.; Panin, V.; Powell, W.; Sakai, H.; Sako, M.; Sato, H.; Shimizu, Y.; Stuhl, L.; Suzuki, H.; Tangwancharoen, S.; Takeda, H.; Uesaka, T.; Yoneda, K.; Zenihiro, J.; Kobayashi, T.; Sumikama, T.; Tako, T.; Nakamura, T.; Kondo, Y.; Togano, Y.; Shikata, M.; Tsubota, J.; Yako, K.; Shimoura, K.; Ota, S.; Kawase, S.; Kubota, Y.; Takaki, M.; Michimasa, S.; Kisamori, K.; Lee, C. S.; Tokieda, H.; Kobayashi, M.; Koyama, S.; Kobayashi, N.; Wakasa, T.; Sakaguchi, S.; Krasznahorkay, A.; Murakami, T.; Nakatsuka, N.; Kaneko, M.; Matsuda, Y.; Mucher, D.; Reichert, S.; Bazin, D.; Lee, J. W.

    2016-01-01

    The charge-exchange (p,n) reaction at 220 MeV has been measured to extract the strength distribution of Gamow-Teller transitions from the doubly magic unstable nucleus 132Sn. A recently developed experimental technique of measuring the (p,n) reaction in inverse kinematics has been applied to the study of unstable nuclei in the mass region around A˜100 for the first time. We have combined the low-energy neutron detector WINDS and the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory (RIBF). The particle identification plot for the reaction residues obtained by the spectrometer provides the clear separation of the CE reaction channel from other background events, enabling us to identify kinematic curves corresponding the (p, n) reaction. Further analysis to reconstruct the excitation energy spectrum is ongoing.

  11. First spectroscopic information from even-even nuclei in the region "southeast" of 132Sn: Neutron-excitation dominance of the 21+ state in 132Cd

    NASA Astrophysics Data System (ADS)

    Wang, H.; Aoi, N.; Takeuchi, S.; Matsushita, M.; Motobayashi, T.; Steppenbeck, D.; Yoneda, K.; Baba, H.; Dombrádi, Zs.; Kobayashi, K.; Kondo, Y.; Lee, J.; Liu, H.; Minakata, R.; Nishimura, D.; Otsu, H.; Sakurai, H.; Sohler, D.; Sun, Y.; Tian, Z.; Tanaka, R.; Vajta, Zs.; Yang, Z.; Yamamoto, T.; Ye, Y.; Yokoyama, R.

    2016-11-01

    The neutron-rich nucleus 132Cd has been studied at the RIKEN Radioactive Isotope Beam Factory using in-beam γ -ray spectroscopy with two-proton removal reactions from 134Sn. A γ -ray transition was observed at 618(8) keV and was assigned to the 21+→0g.s . + decay. The 21+ state provides the first spectroscopic information from the even-even nuclei located in the region "southeast" of the doubly magic nucleus 132Sn. By comparing with the 21+ excitation energies in the semimagic nuclei 134Sn and 130Cd, it is found that neutron excitations dominate the 21+ state in 132Cd, in a similar manner to 136Te. The results are discussed in terms of proton-neutron configuration mixing.

  12. Quadrupole moments of some doubly-even molibden nuclei and the onset of collectivity

    SciTech Connect

    Turkan, N.; Ibis, I.; Maras, I.

    2012-07-15

    A good description of the quadrupole moments is obtained by investigating {sup 94,96,98,100,102,104,106,108}Mo isotopes in terms of the interacting boson model. After the positiveparity states and electromagnetic-transition rates B(E2) of even-mass Mo nuclei were calculated it was seen that there is a good agreement between the obtained results and some previous experimental data. At the end of the quadrupole moment calculations it was proved that the results agree well with the previous experimental data.

  13. Prediction of collective characteristics for ion ensembles in quadrupole ion traps without trajectory simulations.

    PubMed

    Goeringer, Douglas E; Viehland, Larry A; Danailov, Daniel M

    2006-07-01

    Fundamental aspects are presented of a two-temperature moment theory for quadrupole ion traps developed via transformation of the Boltzmann equation. Solutions of the moment equations correspond to changes in the ensemble average for any function of ion velocity, because the Boltzmann equation reflects changes to an ion distribution as a whole. The function of primary interest in this paper is the ion effective temperature and its behavior during ion storage and resonance excitation. Calculations suggest that increases in ion effective temperature during resonance excitation are due primarily to power absorption from the main RF trapping field rather than from the dipolar excitation signal. The dipolar excitation signal apparently serves mainly to move ions into regions of the ion trap where the RF electric field, and thus ion RF heating, is greater than near the trap center. Both ideal and non-ideal ion trap configurations are accounted for in the moment equations by incorporating parameterized variables a and q , which are modified versions of the commonly used forms for the DC and AC ring voltages, and b and d , which are new forms that account for the voltages applied to the endcaps. Besides extending the applicability of the moment equations to non-ideal quadrupole ion traps, the modified versions of the parameterized variables can have additional utility. Calculation of the spatial dependence of ion secular oscillation frequencies is demonstrated as an example.

  14. Prediction of Collective Characteristics for Ion Ensembles in Quadrupole Ion Traps Without Trajectory Simulations

    SciTech Connect

    Goeringer, Doug; Viehland, Mr. Larry A.; Danailov, Daniel M.

    2006-01-01

    Fundamental aspects are presented of a two-temperature moment theory for quadrupole ion traps developed via transformation of the Boltzmann equation. Because the Boltzmann equation reflects changes to an ion distribution as a whole, the resulting general moment equation describes changes in the ensemble average for any function of ion velocity. Thus, the system of differential equations, formed from the general moment equation, can be solved directly (normally, by numerical methods) for average values of the velocity and of the effective temperature (or equivalently, center-of-mass energy), each as a function of time and position. The equations contain parameterized variables ! a and ! q , which are similar to those commonly used in ion trap studies, and ! b and ! d , which are parameterized forms of the voltages applied to the endcaps, to account for both ideal and commonly used ion trap configurations. Examples illustrate some of the capabilities of moment theory for predicting the time- and position-dependent characteristics of ion ensembles during various processes in ion traps of selected configurations.

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

    SciTech Connect

    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 β+/EC decay of 124Cs with the 8π γ-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, $B(E2; 2^+_3 → 0^+_2)$ = 78(13) W.u. and $B(E2; 2^+_4 → 0^+_3)$ = 53(12) W.u. were determined. The $0^+_3$ 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.

  16. Enhanced Quadrupole Collectivity at N=40: The Case of Neutron-Rich Fe Isotopes

    SciTech Connect

    Rother, W.; Dewald, A.; Fransen, C.; Hackstein, M.; Jolie, J.; Pissulla, Th.; Zell, K.-O.; Iwasaki, H.; Baugher, T.; Brown, B. A.; Gade, A.; Glasmacher, T.; McDaniel, S.; Ratkiewicz, A.; Voss, P.; Walsh, K. A.; Lenzi, S. M.; Ur, C. A.; Starosta, K.; Bazin, D.

    2011-01-14

    The transition rates for the 2{sub 1}{sup +} states in {sup 62,64,66}Fe were studied using the recoil distance Doppler-shift technique applied to projectile Coulomb excitation reactions. The deduced E2 strengths illustrate the enhanced collectivity of the neutron-rich Fe isotopes up to N=40. The results are interpreted using the generalized concept of valence proton symmetry which describes the evolution of nuclear structure around N=40 as governed by the number of valence protons with respect to Z{approx_equal}30. The trend of collectivity suggested by the experimental data is described by state-of-the-art shell-model calculations with a new effective interaction developed for the fpgd valence space.

  17. Enhanced quadrupole collectivity at N = 40: the case of neutron-rich Fe isotopes.

    PubMed

    Rother, W; Dewald, A; Iwasaki, H; Lenzi, S M; Starosta, K; Bazin, D; Baugher, T; Brown, B A; Crawford, H L; Fransen, C; Gade, A; Ginter, T N; Glasmacher, T; Grinyer, G F; Hackstein, M; Ilie, G; Jolie, J; McDaniel, S; Miller, D; Petkov, P; Pissulla, Th; Ratkiewicz, A; Ur, C A; Voss, P; Walsh, K A; Weisshaar, D; Zell, K-O

    2011-01-14

    The transition rates for the 2(1)+ states in (62,64,66)Fe were studied using the recoil distance Doppler-shift technique applied to projectile Coulomb excitation reactions. The deduced E2 strengths illustrate the enhanced collectivity of the neutron-rich Fe isotopes up to N = 40. The results are interpreted using the generalized concept of valence proton symmetry which describes the evolution of nuclear structure around N = 40 as governed by the number of valence protons with respect to Z ≈ 30. The trend of collectivity suggested by the experimental data is described by state-of-the-art shell-model calculations with a new effective interaction developed for the fpgd valence space.

  18. On the quadrupole collectivity in the yrast band of 168Yb

    NASA Astrophysics Data System (ADS)

    Petkov, P.; Dewald, A.; Möller, O.; Deloncle, I.; Chapman, R.; Pascu, S.; Bucurescu, D.; Tonev, D.; Reese, M.; Fransen, C.; Araddad, S. Y.; Asova, G.; Copnell, J.; Goutev, N.; Hackstein, M.; Jolie, J.; Lisle, J. C.; Mo, J. N.; Pissulla, Th.; Rother, W.; Smith, A. G.; Tenereiro, C.; Thompson, D. M.; Zell, K. O.

    2017-01-01

    The lifetimes of eight lower spin levels of the yrast band in 168Yb, populated via the 154Sm(18O,4n) and 124Sn(48Ca,4n) reactions, were measured, six of them for the first time, by means of the recoil-distance Doppler-shift method. Two versions of the differential decay-curve method have been applied for the data analysis resulting in a very good agreement. The reduced transition probabilities indicate some reduction of the collectivity for states just above the 61+ level, i.e. well below the band-crossing. The reasons of this effect are discussed in terms of an interaction between the ground-state band and yet unknown part of the two-quasiparticle (ν13/2) spin-aligned S-band by invoking the shell-structure or alternatively/additionally, as changes in the internal structure/shape induced by the rotation.

  19. Mapping quadrupole collectivity in the Cd isotopes: The breakdown of harmonic vibrational motion

    SciTech Connect

    Garrett, P. E.; Green, K. L.; Bangay, J.; Varela, A. Diaz; Sumithrarachchi, C. S.; Bandyopadhyay, D. S.; Bianco, L.; Demand, G. A.; Finlay, P.; Grinyer, G. F.; Leach, K. G.; Phillips, A. A.; Schumaker, M. A.; Svensson, C. E.; Wong, J.; Austin, R. A. E.; Colosimo, S.; Ball, G. C.; Garnsworthy, A. B.; Hackman, G.

    2011-10-28

    The stable Cd isotopes have long been used as paradigms for spherical vibrational motion. Extensive investigations with in-beam {gamma} spectroscopy have resulted in very-well-established level schemes, including many lifetimes or lifetime limits. A programme has been initiated to complement these studies with very-high-statistics {beta} decay using the 8{pi} spectrometer at the TRIUMF radioactive beam facility. The decays of {sup 112}In and {sup 112}Ag have been studied with an emphasis on the observation of, or the placement of stringent limits on, low-energy branches between potential multi-phonon levels. A lack of suitable 0{sup +} or 2{sup +} three-phonon candidates has been revealed. Further, the sum of the B(E2) strength from spin 0{sup +} and 2{sup +} states up to 3 MeV in excitation energy to the assigned two-phonon levels falls far short of the harmonic-vibrational expectations. This lack of strength points to the failing of collective models based on vibrational phonon structures.

  20. First observation of γ rays emitted from excited states south-east of 132Sn: The π g9/2 -1⊗ν f7 /2 multiplet of In13283

    NASA Astrophysics Data System (ADS)

    Jungclaus, A.; Gargano, A.; Grawe, H.; Taprogge, J.; Nishimura, S.; Doornenbal, P.; Lorusso, G.; Shimizu, Y.; Simpson, G. S.; Söderström, P.-A.; Sumikama, T.; Xu, Z. Y.; Baba, H.; Browne, F.; Fukuda, N.; Gernhäuser, R.; Gey, G.; Inabe, N.; Isobe, T.; Jung, H. S.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kwon, Y. K.; Li, Z.; Sakurai, H.; Schaffner, H.; Steiger, K.; Suzuki, H.; Takeda, H.; Vajta, Zs.; Watanabe, H.; Wu, J.; Yagi, A.; Yoshinaga, K.; Bönig, S.; Coraggio, L.; Daugas, J.-M.; Drouet, F.; Gadea, A.; Ilieva, S.; Itaco, N.; Kröll, T.; Montaner-Pizá, A.; Moschner, K.; Mücher, D.; Nishibata, H.; Odahara, A.; Orlandi, R.; Wendt, A.

    2016-04-01

    For the first time, the γ decay of excited states has been observed in a nucleus situated in the quadrant south-east of doubly magic 132Sn, a region in which experimental information so far is limited to ground-state properties. Six γ rays with energies of 50, 86, 103, 227, 357, and 602 keV were observed following the β -delayed neutron emission from Cd13385, populated in the projectile fission of a 238U beam at the Radioactive Isotope Beam Factory at RIKEN within the EURICA project. The new experimental information is compared to the results of a modern realistic shell-model calculation, the first one in this region very far from stability, focusing in particular on the π 0 g9/2 -1⊗ν 1 f7 /2 particle-hole multiplet in In13283. In addition, theoretical estimates based on a scaling of the two-body matrix elements for the π h11/2 -1⊗ν g9 /2 analog multiplet in Tl208127, one major proton and one major neutron shell above, are presented.

  1. Fermilab Tevatron quadrupoles

    SciTech Connect

    Cooper, W.E.; Fisk, H.E.; Gross, D.A.; Lundy, R.A.; Schmidt, E.E.; Turkot, F.

    1983-03-01

    Details on the design, construction, and performance tests of Energy Saver/Doubler quadrupoles are presented along with recent data from the test of a special high gradient low beta prototype quadrupole.

  2. Quadrupole ion traps.

    PubMed

    March, Raymond E

    2009-01-01

    The extraordinary story of the three-dimensional radiofrequency quadrupole ion trap, accompanied by a seemingly unintelligible theoretical treatment, is told in some detail because of the quite considerable degree of commercial success that quadrupole technology has achieved. The quadrupole ion trap, often used in conjunction with a quadrupole mass filter, remained a laboratory curiosity until 1979 when, at the American Society for Mass Spectrometry Conference in Seattle, George Stafford, Jr., of Finnigan Corp., learned of the Masters' study of Allison Armitage of a combined quadrupole ion trap/quadrupole mass filter instrument for the observation of electron impact and chemical ionization mass spectra of simple compounds eluting from a gas chromatograph. Stafford developed subsequently the mass-selective axial instability method for obtaining mass spectra from the quadrupole ion trap alone and, in 1983, Finnigan Corp. announced the first commercial quadrupole ion trap instrument as a detector for a gas chromatograph. In 1987, confinement of ions generated externally to the ion trap was demonstrated and, soon after, the new technique of electrospray ionization was shown to be compatible with the ion trap. Copyright 2009 Wiley Periodicals, Inc.

  3. Superconducting magnetic quadrupole

    SciTech Connect

    Kim, J.W.; Shepard, K.W.; Nolen, J.A.

    1995-08-01

    A design was developed for a 350 T/m, 2.6-cm clear aperture superconducting quadrupole focussing element for use in a very low q/m superconducting linac as discussed below. The quadrupole incorporates holmium pole tips, and a rectangular-section winding using standard commercially-available Nb-Ti wire. The magnet was modeled numerically using both 2D and 3D codes, as a basis for numerical ray tracing using the quadrupole as a linac element. Components for a prototype singlet are being procured during FY 1995.

  4. Characterization of organic gunshot residues in lead-free ammunition using a new sample collection device for liquid chromatography-quadrupole time-of-flight mass spectrometry.

    PubMed

    Benito, Sandra; Abrego, Zuriñe; Sánchez, Alicia; Unceta, Nora; Goicolea, M Aranzazu; Barrio, Ramón J

    2015-01-01

    The identification of characteristic organic gunshot residues (OGSR) provides conclusive evidence in the elucidation of elemental profiles when lead-free ammunition is fired. OGSR also prevents false negatives. Toward this aim, a quick and efficient method based on liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF) was developed to detect and identify 18 gunpowder additives in gunshot residues (GSR). The unequivocal identification of target analytes was assured by using MS/MS mode. Swabs were compared with home-modified tape lift supports covered with a PTFE layer to determine the better sampling technique. The modified tape lift provided better extraction recoveries and enabled the analysis of inorganic and organic GSR simultaneously. The developed method was applied to the analysis of GSR from four different lead-free ammunitions. Diphenylamine and its nitrated degradation products and centralites were identified in all samples, providing strong evidence of GSR.

  5. Correcting Quadrupole Roll in Magnetic Lenses with Skew Quadrupoles

    SciTech Connect

    Walstrom, Peter Lowell

    2014-11-10

    Quadrupole rolls (i.e. rotation around the magnet axis) are known to be a significant source of image blurring in magnetic quadrupole lenses. These rolls may be caused by errors in mechanical mounting of quadrupoles, by uneven radiation-induced demagnetization of permanent-magnet quadrupoles, etc. Here a four-quadrupole ×10 lens with so-called ”Russian” or A -B B-A symmetry is used as a model problem. Existing SLAC 1/2 in. bore high-gradient quadrupoles are used in the design. The dominant quadrupole roll effect is changes in the first-order part of the transfer map (the R matrix) from the object to the image plane (Note effects on the R matrix can be of first order in rotation angle for some R-matrix elements and second order in rotation angle for other elements, as shown below). It is possible to correct roll-induced image blur by mechanically adjusting the roll angle of one or more of the quadrupoles. Usually, rotation of one quadrupole is sufficient to correct most of the combined effect of rolls in all four quadrupoles. There are drawbacks to this approach, however, since mechanical roll correction requires multiple entries into experimental area to make the adjustments, which are made according to their effect on images. An alternative is to use a single electromagnetic skew quadrupole corrector placed either between two of the quadrupoles or after the fourth quadrupole (so-called “non-local” correction). The basic feasibility of skew quadrupole correction of quadrupole roll effects is demonstrated here. Rolls of the third lens quadrupole of up to about 1 milliradian can be corrected with a 15 cm long skew quadrupole with a gradient of up to 1 T/m. Since the effect of rolls of the remaining three lens quadrupoles are lower, a weaker skew quadrupole can be used to correct them. Non-local correction of quadrupole roll effects by skew quadrupoles is shown to be about one-half as effective as local correction (i.e. rotating individual quadrupoles to zero

  6. Variable Permanent Magnet Quadrupole

    SciTech Connect

    Mihara, T.; Iwashita, Y.; Kumada, M.; Spencer, C.M.; /SLAC

    2007-05-23

    A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments.

  7. MQXFS1 Quadrupole Design Report

    SciTech Connect

    Ambrosio, Giorgio

    2016-04-14

    This report presents the reference design of MQXFS1, the first 1.5 m prototype of the low-beta quadrupoles (MQXF) for the LHC High Luminosity Upgrade. The MQXF quadrupoles have 150 mm aperture, coil peak field of about 12 T, and use $Nb_{3}Sn$ conductor. The design is based on the LARP HQ quadrupoles, which had 120 mm aperture. MQXFS1 has 1st generation cable cross-section and magnetic design.

  8. Quadrupole-enhanced Raman scattering.

    PubMed

    Hastings, Simon P; Swanglap, Pattanawit; Qian, Zhaoxia; Fang, Ying; Park, So-Jung; Link, Stephan; Engheta, Nader; Fakhraai, Zahra

    2014-09-23

    Dark, nonradiating plasmonic modes are important in the Raman enhancement efficiency of nanostructures. However, it is challenging to engineer such hotspots with predictable enhancement efficiency through synthesis routes. Here, we demonstrate that spiky nanoshells have designable quadrupole resonances that efficiently enhance Raman scattering with unprecedented reproducibility on the single particle level. The efficiency and reproducibility of Quadrupole Enhanced Raman Scattering (QERS) is due to their heterogeneous structure, which broadens the quadrupole resonance both spatially and spectrally. This spectral breadth allows for simultaneous enhancement of both the excitation and Stokes frequencies. The quadrupole resonance can be tuned by simple modifications of the nanoshell geometry. The combination of tunability, high efficiency, and reproducibility makes these nanoshells an excellent candidate for applications such as biosensing, nanoantennaes, and photovoltaics.

  9. Geometry and properties of the plasma in a quadrupole ion pump

    NASA Technical Reports Server (NTRS)

    Schwarz, H.

    1977-01-01

    The diameter of the plasma in a quadrupole ionization gauge and quadrupole ion pump has been measured as a function of pressure. The radio-frequency quadrupole systems are tuned in such a way that electrons remain on stable trajectories in the center of the tube. Being emitted at one end, the electrons encounter an inverted field at the other end so that they travel on spiral paths back and forth until they collide with the rest gas molecules, producing ions which are collected as an ion current at a cylinder surrounding the four hyperbolically shaped quadrupole electrodes.

  10. Quadrupole Induced Resonant Particle Transport

    NASA Astrophysics Data System (ADS)

    Gilson, Erik; Fajans, Joel

    1999-11-01

    We have performed experiments that explore the effects of a magnetic quadrupole field on a pure electron plasma confined in a Malmberg-Penning trap. A model that we have developed describes the shape of the plasma and shows that a certain class of resonant particles follows trajectories that take them out of the plasma. Even though the quadrupole field destroys the cylindrical symmetry of the system, our theory predicts that if the electrons are off resonance, then the lifetime of the plasma will not be greatly affected by the quadrupole field. Our preliminary experimental results show that the shape of the plasma and the plasma lifetime agree with our model. We are investigating the scaling of this behavior with various experimental parameters such as the plasma length, density, and strength of the quadrupole field. In addition to being an example of resonant particle transport, this effect may find practical applications in experiments that plan to use magnetic quadrupole neutral atom traps to confine anti-hydrogen created in double-well positron/anti-proton Malmberg-Penning traps. (ATHENA Collaboration.)

  11. Quadrupole Induced Resonant Particle Transport

    NASA Astrophysics Data System (ADS)

    Gilson, Erik; Fajans, Joel

    1998-11-01

    We have performed experiments that explore the effects of a magnetic quadrupole field on a pure electron plasma confined in a Penning-Malmberg trap. A model that we have developed describes the shape of the plasma and shows that a certain class of resonant particles follows trajectories that take them out of the plasma. Even though the quadrupole field destroys the cylindrical symmetry of the system, our theory predicts that if the electrons are off resonance, then the lifetime of the plasma will not be greatly affected by the quadrupole field. Our preliminary experimental results show that the shape of the plasma and the plasma lifetime agree with our model. We are investigating the scaling of this behavior with various experimental parameters such as the plasma length, density, and strength of the quadrupole field. In addition to being an example of resonant particle transport, this effect may find practical applications in experiments that plan to use magnetic quadrupole neutral atom traps to confine anti-hydrogen created in double-well positron/anti-proton Penning-Malmberg traps. (ATHENA Collaboration.)

  12. Quadrupole moment of 203Fr

    NASA Astrophysics Data System (ADS)

    Wilkins, S. G.; Lynch, K. M.; Billowes, J.; Binnersley, C. L.; Bissell, M. L.; Cocolios, T. E.; Goodacre, T. Day; de Groote, R. P.; Farooq-Smith, G. J.; Flanagan, K. T.; Franchoo, S.; Ruiz, R. F. Garcia; Gins, W.; Heylen, H.; Koszorús, Á.; Neyens, G.; Stroke, H. H.; Vernon, A. R.; Wendt, K. D. A.; Yang, X. F.

    2017-09-01

    The spectroscopic electric quadrupole moment of the neutron-deficient francium isotope 203Fr was measured by using high-resolution collinear resonance ionization spectroscopy (CRIS) at the CERN Isotope Separation On-Line Device (ISOLDE) facility. A remeasurement of the 207Fr quadrupole moment was also performed, resulting in a departure from the established literature value. A sudden increase in magnitude of the 203Fr quadrupole moment, with respect to the general trend in the region, points to an onset of static deformation at N =116 in the 87Fr isotopic chain. Calculation of the static and total deformation parameters show that the increase in static deformation only cannot account for the observed departure of its relative charge radius from the 82Pb chain.

  13. Nuclear quadrupole resonance spectra database

    NASA Astrophysics Data System (ADS)

    Chihara, H.

    A computer-readable file of numerical data of nuclear quadrupole resonance frequency is being built which also serves as a bibliographic file. The data are compiled by reviewing original papers, reprints, and published data books and retrieving such data elements as substance names, nuclear mass number, temperature of measurements, resonance frequencies, nuclear quadrupole coupling constants, asymmetry parameters, and keywords. The database contains, if available, CAS registry number, molecular formulas and systematic names, and other synonyms of chemical substances. About 800 records have been loaded for online, TSS search through the Computer Center of Osaka University.

  14. Nuclear Quadrupole Moments and Nuclear Shell Structure

    DOE R&D Accomplishments Database

    Townes, C. H.; Foley, H. M.; Low, W.

    1950-06-23

    Describes a simple model, based on nuclear shell considerations, which leads to the proper behavior of known nuclear quadrupole moments, although predictions of the magnitudes of some quadrupole moments are seriously in error.

  15. Accretion disks around a mass with quadrupole

    NASA Astrophysics Data System (ADS)

    Abishev, M.; Boshkayev, K.; Quevedo, H.; Toktarbay, S.

    We consider the stability properties of circular orbits of test particles moving around a mass with quadrupole. We show that the quadrupole modifies drastically the properties of an accretion disk made of such test particles.

  16. Simultaneous quadrupole and octupole shape phase transitions in Thorium

    NASA Astrophysics Data System (ADS)

    Li, Z. P.; Song, B. Y.; Yao, J. M.; Vretenar, D.; Meng, J.

    2013-11-01

    The evolution of quadrupole and octupole shapes in Th isotopes is studied in the framework of nuclear Density Functional Theory. Constrained energy maps and observables calculated with microscopic collective Hamiltonians indicate the occurrence of a simultaneous quantum shape phase transition between spherical and quadrupole-deformed prolate shapes, and between non-octupole and octupole-deformed shapes, as functions of the neutron number. The nucleus 224Th is closest to the critical point of a double phase transition. A microscopic mechanism of this phenomenon is discussed in terms of the evolution of single-nucleon orbitals with deformation.

  17. Quadrupole magnets for the SSC

    SciTech Connect

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

    1992-08-01

    At LBL, we have designed, constructed, and tested ten models (4-1meter, 6-5meter) of the Superconducting Super Collider (SSC) main-ring 5 meter focusing quadrupole magnet (211Tesla/meter). The results of this program are herein summarized.

  18. 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.

  19. Probing the neutron skin thickness in collective modes of excitation

    NASA Astrophysics Data System (ADS)

    Paar, N.; Horvat, A.

    2014-03-01

    Nuclear collective motion provides valuable constraint on the size of neutron-skin thickness and the properties of nuclear matter symmetry energy. By employing relativistic nuclear energy density functional (RNEDF) and covariance analysis related to χ2 fitting of the model parameters, relevant observables are identified for dipole excitations, which strongly correlate with the neutron-skin thickness (rnp), symmetry energy at saturation density (J) and slope of the symmetry energy (L). Using the RNEDF framework and experimental data on pygmy dipole strength (68Ni, 132Sn, 208Pb) and dipole polarizability (208Pb), it is shown how the values of J, and L, and rnp are constrained. The isotopic dependence of moments associated to dipole excitations in 116-136Sn shows that the low-energy dipole strength and polarizability in neutron-rich nuclei display strong sensitivity to the symmetry energy parameter J, more pronounced than in isotopes with moderate neutron-to-proton number ratios.

  20. A Vibrating Wire System For Quadrupole Fiducialization

    SciTech Connect

    Wolf, Zachary

    2010-12-13

    A vibrating wire system is being developed to fiducialize the quadrupoles between undulator segments in the LCLS. This note provides a detailed analysis of the system. The LCLS will have quadrupoles between the undulator segments to keep the electron beam focused. If the quadrupoles are not centered on the beam axis, the beam will receive transverse kicks, causing it to deviate from the undulator axis. Beam based alignment will be used to move the quadrupoles onto a straight line, but an initial, conventional alignment must place the quadrupole centers on a straight line to 100 {micro}m. In the fiducialization step of the initial alignment, the position of the center of the quadrupole is measured relative to tooling balls on the outside of the quadrupole. The alignment crews then use the tooling balls to place the magnet in the tunnel. The required error on the location of the quadrupole center relative to the tooling balls must be less than 25 {micro}m. In this note, we analyze a system under construction for the quadrupole fiducialization. The system uses the vibrating wire technique to position a wire onto the quadrupole magnetic axis. The wire position is then related to tooling balls using wire position detectors. The tooling balls on the wire position detectors are finally related to tooling balls on the quadrupole to perform the fiducialization. The total 25 {micro}m fiducialization error must be divided between these three steps. The wire must be positioned onto the quadrupole magnetic axis to within 10 {micro}m, the wire position must be measured relative to tooling balls on the wire position detectors to within 15 {micro}m, and tooling balls on the wire position detectors must be related to tooling balls on the quadrupole to within 10 {micro}m. The techniques used in these three steps will be discussed. The note begins by discussing various quadrupole fiducialization techniques used in the past and discusses why the vibrating wire technique is our method

  1. A Merged Quadrupole-Calorimeter for CEPC

    NASA Astrophysics Data System (ADS)

    Talman, Richard; Hauptman, John

    The luminosity 𝓛 of colliding beams in a storage ring such as CEPC depends strongly on l*, the half-length of the free space centered on the intersection point (IP). l* is also the length from the IP to the front edges of the two near-in quadrupoles that are focusing the counter-circulating beams to the IP spot. The detector length cannot, therefore, exceed 2l*. Since 𝓛 increases strongly with decreasing l*, there is incentive for reducing l*; but this requires the detector to be shorter than desirable. This paper proposes a method for integrating these adjacent quadrupoles into the particle detector to retain (admittedly degraded) active particle detection of those forward going particles that would otherwise be obscured by the quadrupole. A gently conical quadrupole shape is more natural for merging the quadrupole into the particle detector than is the analytically exact cylindrical shape. This is true whether or not the calorimeter is integrated. It will be the task of accelerator physicists to determine the extent to which deviation from the pure quadrupole field compromises (or improves) accelerator performance. Superficially, both the presence of strongest gradient close to the IP and largest aperture farther from the IP seem to be advantageous. A tentative design for this merged, quadrupole-calorimeter is given.

  2. A merged quadrupole-calorimeter for CEPC

    NASA Astrophysics Data System (ADS)

    Talman, Richard; Hauptman, John

    2016-11-01

    The luminosity ℒ of colliding beams in a storage ring such as CEPC depends strongly on l∗, the half-length of the free space centered on the intersection point (IP). l∗ is also the length from the IP to the front edges of the two near-in quadrupoles that are focusing the counter-circulating beams to the IP spot. The detector length cannot, therefore, exceed 2l∗. Since ℒ increases strongly with decreasing l∗, there is incentive for reducing l∗; but this requires the detector to be shorter than desirable. This paper proposes a method for integrating these adjacent quadrupoles into the particle detector to retain (admittedly degraded) active particle detection of those forward going particles that would otherwise be obscured by the quadrupole. A gently conical quadrupole shape is more natural for merging the quadrupole into the particle detector than is the analytically exact cylindrical shape. This is true whether or not the calorimeter is integrated. It will be the task of accelerator physicists to determine the extent to which deviation from the pure quadrupole field compromises (or improves) accelerator performance. Superficially, both the presence of strongest gradient close to the IP and largest aperture farther from the IP seem to be advantageous. A tentative design for this merged, quadrupole-calorimeter is given.

  3. QUADRUPOLE BEAM-BASED ALIGNMENT AT RHIC.

    SciTech Connect

    NIEDZIELA, J.; MONTAG, C.; SATOGATA, T.

    2005-05-16

    Successful implementation of a beam-based alignment algorithm, tailored to different types of quadrupoles at RHIC, provides significant benefits to machine operations for heavy ions and polarized protons. This algorithm was used to calibrate beam position monitor centers relative to interaction region quadrupoles to maximize aperture. This approach was also used to determine the optimal orbit through transition jump quadrupoles to minimize orbit changes during the transition jump for heavy ion acceleration. This paper provides background discussion and results from first measurements during the RHIC 2005 run.

  4. Clusterization and quadrupole deformation in nuclei

    SciTech Connect

    Cseh, J.; Algora, A.; Antonenko, N. V.; Jolos, R. V.; Scheid, W.; Darai, J.; Hess, P. O.

    2006-04-26

    We study the interrelation of the clusterization and quadrupole deformation of atomic nuclei, by applying cluster models. Both the energetic stability and the exclusion principle is investigated. Special attention is paid to the relative orientations of deformed clusters.

  5. Nonuniform radiation damage in permanent magnet quadrupoles.

    PubMed

    Danly, C R; Merrill, F E; Barlow, D; Mariam, F G

    2014-08-01

    We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL's pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

  6. Nonuniform radiation damage in permanent magnet quadrupoles

    SciTech Connect

    Danly, C. R.; Merrill, F. E.; Barlow, D.; Mariam, F. G.

    2014-08-15

    We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL’s pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

  7. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, Roman O.

    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.

  8. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, R.O.

    1997-01-21

    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. 10 figs.

  9. Integrally formed radio frequency quadrupole

    DOEpatents

    Abbott, Steven R.

    1989-01-01

    An improved radio frequency quadrupole (10) is provided having an elongate housing (11) with an elongate central axis (12) and top, bottom and two side walls (13a-d) symmetrically disposed about the axis, and vanes (14a-d) formed integrally with the walls (13a-d), the vanes (14a-d) each having a cross-section at right angles to the central axis (12) which tapers inwardly toward the axis to form electrode tips (15a-d) spaced from each other by predetermined distances. Each of the four walls (13a-d), and the vanes (14a-d) integral therewith, is a separate structural element having a central lengthwise plane (16) passing through the tip of the vane, the walls (13a-d) having flat mounting surfaces (17, 18) at right angles to and parallel to the control plane (16), respectively, which are butted together to position the walls and vane tips relative to each other.

  10. 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.

  11. 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.

  12. Quadrupole-bound anions: efficacy of positive versus negative quadrupole moments.

    PubMed

    Garrett, W R

    2012-02-07

    A pseudopotential method is utilized to study the critical stability of model anions formed by long-range quadrupolar molecular potentials. Results indicate that critical quadrupole moments of simple point-charge triads do not serve well as predictors of real quadrupole-bound anions of systems with negative moments.

  13. Ultra performance liquid chromatography coupled with electrospray and atmospheric pressure chemical ionization (ESCi)-quadrupole time-of-flight mass spectrometry with novel mass spectrometry(Elevated Energy) (MS(E)) data collection technique: determination and pharmacokinetics, tissue distribution and biliary excretion study of ergone in rat.

    PubMed

    Zhao, Ying-Yong; Cheng, Xian-Long; Wei, Feng; Bai, Xu; Lin, Rui-Chao

    2012-07-01

    Ergosta-4,6,8(14),22-tetraen-3-one (ergone) has been proved to have novel antitumor effects on HepG2 cells. The aim of this study was to investigate the pharmacokinetics, tissue distribution, and biliary excretion of ergone in rats following a single oral administration (5, 10, and 20 mg/kg). The levels of ergone in plasma, tissues, and bile were measured by ultra performance liquid chromatography coupled with electrospray and atmospheric pressure chemical ionization (ESCi)-quadrupole time-of-flight mass spectrometry with novel mass spectrometry(Elevated Energy) (MS(E)) data collection technique method. The results show ergone was distributed and eliminated from rat plasma and in non-linear pharmacokinetics from a dose range of 5-20 mg/kg. The ergone was found to distribute widely in the internal organs, with tissue concentrations in order of lungs, spleen, liver, intestine, kidneys, heart, stomach, parorchis, teasticles, and brain. At 12 h after dosing, the tissue concentrations in the organs were markedly decreased. The lungs, spleen, and liver were the dominant organs with high tissue concentrations that might be the primary sites for metabolism and elimination of ergone. Total recoveries of ergone within 24 h in bile were 34.14%.

  14. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    SciTech Connect

    Rainer Meinke Carl Goodzeit Penny Ball Roger Bangerter

    2003-10-01

    The goal of this research was to develop concepts for affordable, fully functional arrays of superconducting quadrupoles for multi-beam transport and focusing in heavy ion fusion (HIF)accelerators. Previous studies by the Virtual National Laboratory (VNL) collaboration have shown that the multi-beam transport system (consisting of alternating gradient quadrupole magnets, a beam vacuum system, and the beam monitor and control system) will likely be one of the most expensive and critical parts of such an accelerator. This statement is true for near-term fusion research accelerators as well as accelerators for the ultimate goal of power production via inertial fusion. For this reason, research on superconducting quadrupole arrays is both timely and important for the inertial fusion energy (IFE) research program. This research will also benefit near-term heavy ion fusion facilities such as the Integrated Research Experiment (IRE)and/or the Integrated Beam Experiment (IBX). We considered a 2-prong approach that addresses the needs of both the nearer and longer term requirements of the inertial fusion program. First, we studied the flat coil quadrupole design that was developed by LLNL; this magnet is 150 mm long with a 50 mm aperture and thus is suitable for near term experiments that require magnets of a small length to aperture ratio. Secondly, we studied the novel double-helix quadrupole (DHQ) design in a small (3 x 3) array configuration; this design can provide an important step to the longer term solution of low-cost, easy to manufacture array constructions. Our Phase I studies were performed using the AMPERES magnetostatic analysis software. Consideration of these results led to plans for future magnet R&D construction projects. The first objective of Phase I was to develop the concept of a superconducting focusing array that meets the specific requirements of a heavy ion fusion accelerator. Detailed parameter studies for such quadrupole arrays were performed

  15. Focusing properties of discrete RF quadrupoles

    NASA Astrophysics Data System (ADS)

    Li, Zhi-Hui; Wang, Zhi-Jun

    2017-08-01

    The particle motion equation for a Radio Frequency (RF) quadrupole is derived. The motion equation shows that the general transform matrix of a RF quadrupole with length less than or equal to 0.5βλ (β is the relativistic velocity of particles and λ is wavelength of radio frequency electromagnetic field) can describe the particle motion in an arbitrarily long RF quadrupole. By iterative integration, the general transform matrix of a discrete RF quadrupole is derived from the motion equation. The transform matrix is in form of a power series of focusing parameter B. It shows that for length less than βλ, the series up to the 2nd order of B agrees well with the direct integration results for B up to 30, while for length less than 0.5βλ, the series up to 1st order is already a good approximation of the real solution for B less than 30. The formula of the transform matrix can be integrated into linac or beam line design code to deal with the focusing of discrete RF quadrupoles. Supported by National Natural Science Foundation of China (11375122, 11511140277) and Strategic Priority Research Program of the Chinese Academy of Sciences (XDA03020705)

  16. Induced CMB quadrupole from pointing offsets

    SciTech Connect

    Moss, Adam; Scott, Douglas; Sigurdson, Kris E-mail: dscott@phas.ubc.ca

    2011-01-01

    Recent claims in the literature have suggested that the WMAP quadrupole is not primordial in origin, and arises from an aliasing of the much larger dipole field because of incorrect satellite pointing. We attempt to reproduce this result and delineate the key physics leading to the effect. We find that, even if real, the induced quadrupole would be smaller than the WMAP value. We discuss reasons why the WMAP data are unlikely to suffer from this particular systematic effect, including the implications for observations of point sources. Given this evidence against the reality of the effect, the similarity between the pointing-offset-induced signal and the actual quadrupole then appears to be quite puzzling. However, we find that the effect arises from a convolution between the gradient of the dipole field and anisotropic coverage of the scan direction at each pixel. There is something of a directional conspiracy here — the dipole signal lies close to the Ecliptic Plane, and its direction, together with the WMAP scan strategy, results in a strong coupling to the Y{sub 2,−1} component in Ecliptic co-ordinates. The dominant strength of this component in the measured quadrupole suggests that one should exercise increased caution in interpreting its estimated amplitude. The Planck satellite has a different scan strategy which does not so directly couple the dipole and quadrupole in this way and will soon provide an independent measurement.

  17. Resonance methods in quadrupole ion traps

    NASA Astrophysics Data System (ADS)

    Snyder, Dalton T.; Peng, Wen-Ping; Cooks, R. Graham

    2017-01-01

    The quadrupole ion trap is widely used in the chemical physics community for making measurements on dynamical systems, both intramolecular (e.g. ion fragmentation reactions) and intermolecular (e.g. ion/molecule reactions). In this review, we discuss linear and nonlinear resonances in quadrupole ion traps, an understanding of which is critical for operation of these devices and interpretation of the data which they provide. The effect of quadrupole field nonlinearity is addressed, with important implications for promoting fragmentation and achieving unique methods of mass scanning. Methods that depend on ion resonances (i.e. matching an external perturbation with an ion's induced frequency of motion) are discussed, including ion isolation, ion activation, and ion ejection.

  18. The Large Quadrupole of Water Molecules

    SciTech Connect

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

    2011-04-07

    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

  19. 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.

  20. The nuclear electric quadrupole moment of copper.

    PubMed

    Santiago, Régis Tadeu; Teodoro, Tiago Quevedo; Haiduke, Roberto Luiz Andrade

    2014-06-21

    The nuclear electric quadrupole moment (NQM) of the (63)Cu nucleus was determined from an indirect approach by combining accurate experimental nuclear quadrupole coupling constants (NQCCs) with relativistic Dirac-Coulomb coupled cluster calculations of the electric field gradient (EFG). The data obtained at the highest level of calculation, DC-CCSD-T, from 14 linear molecules containing the copper atom give rise to an indicated NQM of -198(10) mbarn. Such result slightly deviates from the previously accepted standard value given by the muonic method, -220(15) mbarn, although the error bars are superimposed.

  1. Microscopic analysis of quadrupole-octupole shape evolution

    NASA Astrophysics Data System (ADS)

    Nomura, Kosuke

    2015-05-01

    We analyze the quadrupole-octupole collective states based on the microscopic energy density functional framework. By mapping the deformation constrained self-consistent axially symmetric mean-field energy surfaces onto the equivalent Hamiltonian of the sdf interacting boson model (IBM), that is, onto the energy expectation value in the boson coherent state, the Hamiltonian parameters are determined. The resulting IBM Hamiltonian is used to calculate excitation spectra and transition rates for the positive- and negative-parity collective states in large sets of nuclei characteristic for octupole deformation and collectivity. Consistently with the empirical trend, the microscopic calculation based on the systematics of β2 - β3 energy maps, the resulting low-lying negative-parity bands and transition rates show evidence of a shape transition between stable octupole deformation and octupole vibrations characteristic for β3-soft potentials.

  2. Nuclear quadrupole resonance studies in semi-metallic structures

    NASA Technical Reports Server (NTRS)

    Murty, A. N.

    1974-01-01

    Both experimental and theoretical studies are presented on spectrum analysis of nuclear quadrupole resonance of antimony and arsenic tellurides. Numerical solutions for secular equations of the quadrupole interaction energy are also discussed.

  3. Low-lying bands with different quadrupole deformation in 155Dy

    NASA Astrophysics Data System (ADS)

    Petkov, P.; Yavahchova, M. S.; Möller, O.; Dewald, A.; Saha, B.; Fitzler, A.; Jessen, K.; Tonev, D.; Klug, T.; Heinze, S.; Jolie, J.; von Brentano, P.; Goutev, N.; Bazzacco, D.; Ur, C. A.; Farnea, C. A.; Axiotis, M.; Lunardi, S.; de Angelis, G.; Napoli, D. R.; Marginean, N.; Martinez, T.; Caprio, M. A.

    2014-03-01

    To investigate the interplay between collective and single particle degrees of freedom in odd nuclei, Recoil distance Doppler-shift and Doppler-shift attenuation lifetime measurements were carried out for levels in 155Dy in coincidence detection of gamma-rays. 26 lifetimes were determined using the Differential decay curve method. Particle plus triaxial rotor model (PTRM) calculations were performed to compare the experimental level scheme and transition strengths with theoretical ones in order to get information on the quadrupole deformation (є,γ) of the bands. As a result, different quadrupole deformations for the one-quasineutron bands at low and medium spins are deduced.

  4. Signature to detect the isovector giant quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Speth, J.; Cha, D.; Klemt, V.; Wambach, J.

    1985-06-01

    We calculate the γ decay from the isoscalar and isovector giant quadrupole resonances in 208Pb into the low-lying spectrum. Whereas the γ decay from the isoscalar giant quadrupole resonance into the first excited 3- state is very small, the corresponding transition from the isovector giant quadrupole resonance is strongly enhanced. According to preliminary calculations, these results hold rather generally for other heavy mass nuclei. We suggest using this property in experimental investigation of the isovector giant quadrupole resonance.

  5. Interrelations between the pairing and quadrupole interactions in the microscopic Shell Model

    NASA Astrophysics Data System (ADS)

    Drumev, K. P.; Georgieva, A. I.

    2016-01-01

    We explore the dynamical symmetries of the shell model number conserving algebra, which define three types of pairing and quadrupole phases, with the aim to obtain the prevailing phase or phase transition for the real nuclear systems in a single shell. This is achieved by establishing a correspondence between each of the pairing bases with the Elliott's SU(3) basis that describes collective rotation of nuclear systems. This allows for a complete classification of the basis states of different number of particles in all the limiting cases. The probability distribution of the SU(3) basis states within theirs corresponding pairing states is also obtained. The relative strengths of dynamically symmetric quadrupole-quadrupole interaction in respect to the isoscalar, isovector and total pairing interactions define a control parameter, which estimates the importance of each term of the Hamiltonian in the correct reproduction of the experimental data for the considered nuclei.

  6. Trade-offs in miniature quadrupole designs.

    PubMed

    Boumsellek, S; Ferran, R J

    2001-06-01

    Pressing needs for miniature mass spectrometers became apparent during the last decade in process monitoring and control, space exploration, and environmental screening. Besides the small footprint, common requirements include low cost, low power consumption, field portability, reliability, autonomy, and ease-of-use. Design concepts and construction technologies of miniaturized quadrupole sensors were guided by cost reduction requirements without sacrifice of performance. The first miniature and complete quadrupole mass spectrometer system was introduced as the Micropole sensor. The concept featured a novel technique to assemble and operate multiple miniature quadrupoles in parallel. The short analyzer length offers a significant advantage by enabling direct mass filtering at pressures up in the 10(-2) torr range. High voltages at higher frequencies (10-20 MHz) are required for acceptable mass resolving powers. Additional trade-offs were uncovered in miniature sensors leading to designs optimized for each class of applications. Real time ray tracing of ions injected and filtered in the quadrupole field is used early in the design stage to predict the performance and reliability of the device.

  7. 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.

  8. 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.

  9. LARP Long Nb3Sn Quadrupole Design.

    SciTech Connect

    Ambrosio,G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidize, G.; Dietderich, D.; Feher, S.; Felice, H.; Ferracin, P.; Ghosh, A.; Hafalia, A.R.; Hannaford, C.R.; Kashikhin, V.V.; Kerby, J.; Lamm, M.; Lietzke, A.; McInturff, A.; Muratore, J.; Nobrega, F.; Novitsky, I.; Sabbi, G.L.; Schmalzle, J.; Tartaglia, M.; Turrioni, D.; Wanderer, P.; Whitson, G.; Zlobin, A.V.

    2007-08-27

    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 Nb{sub 3}Sn conductor. The goal of these magnets is to be a proof of principle that Nb{sub 3}Sn 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.

  10. LARP Long Nb3Sn Quadrupole Design

    SciTech Connect

    Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S.; Chlachidize, G.; Dietderich, D.; Feher, S.; Ferracin, P.; Ghosh, A.; Hafalia, R.; Hannaford, R.; Kashikhin, V.V.; Kerby, J.; Lamm, M.; Lietzke, A.; McInturff, A.; Muratore, J.; Nobrega, F.; Novitsky, I.; Sabbi, G.L.; Schmalzle, J.; Tartaglia, M.; Turrioni, D.; Wanderer, P.; Whitson, G.; Zlobin, A.V.

    2008-06-01

    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 Nb{sub 3}Sn conductor. The goal of these magnets is to be a proof of principle that Nb{sub 3}Sn 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.

  11. Permanent-magnet quadrupoles in RFQ Linacs

    SciTech Connect

    Lysenko, W.P.; Wang, T.F.

    1985-10-01

    We investigated the possibility of increasing the current-carrying capability of radio-frequency quadrupole (RFQ) linear accelerators by adding permanentmagnet quadrupole (PMQ) focusing to the existing transverse focusing provided by the rf electric field. Increased transverse focusing would also allow shortening RFQ linacs by permitting a larger accelerating gradient, which is normally accompanied by an undesirable increased transverse rf defocusing effect. We found that PMQs were not helpful in increasing the transverse focusing strength in an RFQ. This conclusion was reached after some particle tracing simulations and some analytical calculations. In our parameter regime, the addition of the magnets increases the betatron frequency but does not result in improved focusing because the increased flutter more than offsets the gain from the increased betatron frequency.

  12. 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.

  13. Radio frequency quadrupole resonator for linear accelerator

    DOEpatents

    Moretti, Alfred

    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.

  14. 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.

  15. Muon cooling in a quadrupole magnet channel

    SciTech Connect

    Neuffer, David; 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.

  16. Superconducting quadrupoles for the SLC final focus

    SciTech Connect

    Erickson, R.; Fieguth, T.; Murray, J.J.

    1987-01-01

    The final focus system of the SLC will be upgraded by replacing the final quadrupoles with higher gradient superconducting magnets positioned closer to the interaction point. The parameters of the new system have been chosen to be compatible with the experimental detectors with a minimum of changes to other final focus components. These parameter choices are discussed along with the expected improvement in SLC performance.

  17. 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.

  18. Quadrupole transitions revealed by Borrmann spectroscopy.

    PubMed

    Pettifer, Robert F; Collins, Stephen P; Laundy, David

    2008-07-10

    The Borrmann effect-a dramatic increase in transparency to X-ray beams-is observed when X-rays satisfying Bragg's law diffract through a perfect crystal. The minimization of absorption seen in the Borrmann effect has been explained by noting that the electric field of the X-ray beam approaches zero amplitude at the crystal planes, thus avoiding the atoms. Here we show experimentally that under conditions of absorption suppression, the weaker electric quadrupole absorption transitions are effectively enhanced to such a degree that they can dominate the absorption spectrum. This effect can be exploited as an atomic spectroscopy technique; we show that quadrupole transitions give rise to additional structure at the L(1), L(2) and L(3) absorption edges of gadolinium in gadolinium gallium garnet, which mark the onset of excitations from 2s, 2p(1/2) and 2p(3/2) atomic core levels, respectively. Although the Borrmann effect served to underpin the development of the theory of X-ray diffraction, this is potentially the most important experimental application of the phenomenon since its first observation seven decades ago. Identifying quadrupole features in X-ray absorption spectroscopy is central to the interpretation of 'pre-edge' spectra, which are often taken to be indicators of local symmetry, valence and atomic environment. Quadrupolar absorption isolates states of different symmetries to that of the dominant dipole spectrum, and typically reveals orbitals that dominate the electronic ground-state properties of lanthanides and 3d transition metals, including magnetism. Results from our Borrmann spectroscopy technique feed into contemporary discussions regarding resonant X-ray diffraction and the nature of pre-edge lines identified by inelastic X-ray scattering. Furthermore, because the Borrmann effect has been observed in photonic materials, it seems likely that the quadrupole enhancement reported here will play an important role in modern optics.

  19. Table of nuclear electric quadrupole moments

    NASA Astrophysics Data System (ADS)

    Stone, N. J.

    2016-09-01

    This Table is a compilation of experimental measurements of static 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 measurement. Experimental data from all quadrupole moment measurements actually provide a value of the product of the moment and the electric field gradient [EFG] acting at the nucleus. Knowledge of the EFG is thus necessary to extract the quadrupole moment. A single recommended moment value is given for each state, based, for each element, wherever possible, upon a standard reference moment for a nuclear state of that element studied in a situation in which the electric field gradient has been well calculated. For several elements one or more subsidiary EFG/moment reference is required and their use is specified. The literature search covers the period to mid-2015.

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

    SciTech Connect

    Lepers, M.; Dulieu, O.; Kokoouline, V.

    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.

  1. Ab initio correlated calculations of rare-gas dimer quadrupoles

    NASA Astrophysics Data System (ADS)

    Donchev, Alexander G.

    2007-10-01

    This paper reports ab initio calculations of rare gas ( RG=Kr , Ar, Ne, and He) dimer quadrupoles at the second order of Møller-Plesset perturbation theory (MP2). The study reveals the crucial role of the dispersion contribution to the RG2 quadrupole in the neighborhood of the equilibrium dimer separation. The magnitude of the dispersion quadrupole is found to be much larger than that predicted by the approximate model of Hunt. As a result, the total MP2 quadrupole moment is significantly smaller than was assumed in virtually all previous related studies. An analytical model for the distance dependence of the RG2 quadrupole is proposed. The model is based on the effective-electron approach of Jansen, but replaces the original Gaussian approximation to the electron density in an RG atom by an exponential one. The role of the nonadditive contribution in RG3 quadrupoles is discussed.

  2. Beta decay and isomer spectroscopy in the 132Sn region: New results from EURICA

    NASA Astrophysics Data System (ADS)

    Jungclaus, A.; Taprogge, J.; Simpson, G. S.; Gey, G.; Nishimura, S.; Doornenbal, P.; Lorusso, G.; Söderström, P.-A.; Sumikama, T.; Xu, Z.; Baba, H.; Browne, F.; Fukuda, N.; Inabe, N.; Isobe, T.; Jung, H. S.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kwon, Y. K.; Li, Z.; Sakurai, H.; Schaffner, H.; Suzuki, H.; Takeda, H.; Vajta, Z.; Watanabe, H.; Wu, J.; Yagi, A.; Yoshinaga, K.; Bönig, S.; Daugas, J.-M.; Drouet, F.; Gernhäuser, R.; Ilieva, S.; Kröll, T.; Montaner-Pizá, A.; Moschner, K.; Mücher, D.; Nishibata, H.; Orlandi, R.; Steiger, K.; Wendt, A.

    2014-09-01

    The first EURICA campaign with high intensity Uranium beams took place at RIKEN in November/December 2012. Within this campaign experiment NP1112-RIBF85 was performed dedicated to the study of the isomeric and beta decays of neutron-rich Cd, In, Sn and Sb isotopes towards and beyond the N=82 neutron shell closure. In this contribution we will first provide information about the status of the analysis of the extensive data set obtained in this experiment and close with a short outlook.

  3. Global properties of nuclei from {sup 100}Sn to {sup 132}Sn

    SciTech Connect

    Isakov, V. I.

    2013-07-15

    The paper presents the results of both microscopical and semi-empirical calculations of single-particle characteristics, nuclear binding, and one-nucleon separation energies of nuclei, as well as their root-mean-square radii, energy levels and transition rates in the long chain of Sn isotopes. We consider nuclei from the extremely neutron-deficient {sup 100}Sn up to neutron excess {sup 136}Sn, where the experimental information is available by now. The comprehensive comparison with the experimental data is carried out.

  4. Nuclear electric quadrupole interactions in liquids entrapped in cavities

    NASA Astrophysics Data System (ADS)

    Furman, Gregory B.; Meerovich, Victor M.; Sokolovsky, Vladimir L.

    2016-12-01

    Liquids entrapped in cavities and containing quadrupole nuclei are considered. The interaction of the quadrupole moment of a nucleus with the electric field gradient is studied. In such a system, molecules are in both rotational and translational Brownian motions which are described by the diffusion equation. Solving this equation, we show that the intra- and intermolecular nuclear quadrupole interactions are averaged to zero in cavities with the size larger than several angstroms.

  5. Noise reduction in negative-ion quadrupole mass spectrometry

    DOEpatents

    Chastagner, Philippe

    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.

  6. 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.

  7. 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.

  8. ANALYTICAL SOLUTIONS OF SINGULAR ISOTHERMAL QUADRUPOLE LENS

    SciTech Connect

    Chu Zhe; Lin, W. P.; Yang Xiaofeng E-mail: linwp@shao.ac.cn

    2013-06-20

    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.

  9. 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

  10. Precise calculations of the deuteron quadrupole moment

    SciTech Connect

    Gross, Franz L.

    2016-06-01

    Recently, two calculations of the deuteron quadrupole moment have have given predictions that agree with the measured value to within 1%, resolving a long-standing discrepancy. One of these uses the covariant spectator theory (CST) and the other chiral effective field theory (cEFT). In this talk I will first briefly review the foundations and history of the CST, and then compare these two calculations with emphasis on how the same physical processes are being described using very different language. The comparison of the two methods gives new insights into the dynamics of the low energy NN interaction.

  11. Nuclear quadrupole resonance echoes from hexamethylenetetramine.

    PubMed

    Ota, Go; Itozaki, Hideo

    2006-10-01

    We investigated the echo phenomenon of nuclear quadrupole resonance (NQR) from hexamethylenetetramine (HMT). We detected the pure NQR echo signal of HMT with a short pulse interval. The intensity of the echo signal increased as the pulse interval time was decreased. We observed that a clean echo signal was generated even when the pulse interval was shorter than the decay time constant T(2)(*). Since the short interval time gives a strong echo, our result insists that shorter interval time is preferred for the NQR detection.

  12. The Pipe-Quadrupole, an Alternative for High Gradient Interaction Region Quadrupole Designs

    SciTech Connect

    Oort, J.M. van; Scanlan, R.M.

    1996-12-12

    In the design of interaction region (IR) quadrupoles for high luminosity colliders such as the LHC or a possible upgrade of the Tevatron, the radiation heating of the coil windings is an important issue. Two obvious solutions to this problem can be chosen. The first is to reduce the heat load by added shielding, increased cooling with fins or using Nb{sub 3}Sn to increase the temperature margin. The second solution eliminates the conductor from the areas with the highest radiation intensity, which are located on the symmetry-axes of the midplanes of the coils. A novel quadrupole design is presented, in which the conductor is wound on four half-moon shaped supports, forming elongated toroid sections. The assembly of the four shapes yields a quadrupole field with an active flux return path, and a void in the high radiation area. This void can be occupied by a liquid helium cooling pipe to lower the temperature of the windings from the inside. The coil layout, harmonic optimization and mechanical design are shown, together with the calculated temperature rise for the radiation load of the LHC interaction region quadrupoles.

  13. 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.

  14. Explosives detection with quadrupole resonance analysis

    NASA Astrophysics Data System (ADS)

    Rayner, Timothy J.; Thorson, Benjamin D.; Beevor, Simon; West, Rebecca; Krauss, Ronald A.

    1997-02-01

    The increase in international terrorist activity over the past decade has necessitated the exploration of new technologies for the detection of plastic explosives. Quadrupole resonance analysis (QRA) has proven effective as a technique for detecting the presence of plastic, sheet, and military explosive compounds in small quantities, and can also be used to identify narcotics such as heroin and cocaine base. QRA is similar to the widely used magnetic resonance (MR) and magnetic resonance imaging (MRI) techniques, but has the considerable advantage that the item being inspected does not need to be immersed in a steady, homogeneous magnetic field. The target compounds are conclusively identified by their unique quadrupole resonance frequencies. Quantum magnetics has develop and introduced a product line of explosives and narcotics detection devices based upon QRA technology. The work presented here concerns a multi-compound QRA detection system designed to screen checked baggage, cargo, and sacks of mail at airports and other high-security facilities. The design philosophy and performance are discussed and supported by test results from field trials conducted in the United States and the United Kingdom. This detection system represents the current state of QRA technology for field use in both commercial and government sectors.

  15. Magnetic quench antenna for MQXF quadrupoles

    DOE PAGES

    Marchevsky, Maxim; Sabbi, GianLuca; Prestemon, Soren; ...

    2016-12-21

    High-field MQXF-series quadrupoles are presently under development by LARP and CERN for the upcoming LHC luminosity upgrade. Quench training and protection studies on MQXF prototypes require a capability to accurately localize quenches and measure their propagation velocity in the magnet coils. The voltage tap technique commonly used for such purposes is not a convenient option for the 4.2-m-long MQXF-A prototype, nor can it be implemented in the production model. We have developed and tested a modular inductive magnetic antenna for quench localization. The base element of our quench antenna is a round-shaped printed circuit board containing two orthogonal pairs ofmore » flat coils integrated with low-noise preamplifiers. The elements are aligned axially and spaced equidistantly in 8-element sections using a supporting rod structure. The sections are installed in the warm bore of the magnet, and can be stacked together to adapt for the magnet length. We discuss the design, operational characteristics and preliminary qualification of the antenna. Lastly, axial quench localization capability with an accuracy of better than 2 cm has been validated during training test campaign of the MQXF-S1 quadrupole.« less

  16. Magnetic quench antenna for MQXF quadrupoles

    SciTech Connect

    Marchevsky, Maxim; Sabbi, GianLuca; Prestemon, Soren; Strauss, Thomas; Stoynev, Stoyan; Chlachidze, Guram

    2016-12-21

    High-field MQXF-series quadrupoles are presently under development by LARP and CERN for the upcoming LHC luminosity upgrade. Quench training and protection studies on MQXF prototypes require a capability to accurately localize quenches and measure their propagation velocity in the magnet coils. The voltage tap technique commonly used for such purposes is not a convenient option for the 4.2-m-long MQXF-A prototype, nor can it be implemented in the production model. We have developed and tested a modular inductive magnetic antenna for quench localization. The base element of our quench antenna is a round-shaped printed circuit board containing two orthogonal pairs of flat coils integrated with low-noise preamplifiers. The elements are aligned axially and spaced equidistantly in 8-element sections using a supporting rod structure. The sections are installed in the warm bore of the magnet, and can be stacked together to adapt for the magnet length. We discuss the design, operational characteristics and preliminary qualification of the antenna. Lastly, axial quench localization capability with an accuracy of better than 2 cm has been validated during training test campaign of the MQXF-S1 quadrupole.

  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. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2016-11-15

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  19. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  20. Monopole, Quadrupole and Pairing: a Shell Model View

    NASA Astrophysics Data System (ADS)

    Zuker, A. P.

    The three main contributions to the nuclear Hamiltonian-monopole, quadrupole and pairing - are analyzed in a shell model context. The first has to be treated phenomenologically, while the other two can be reliably extracted from the realistic interactions. Due to simple scaling properties, the realistic quadrupole and pairing interactions eliminate the tendency to collapse of their conventional counterparts, while retaining their basic simplicity.

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

    DOEpatents

    Maschke, Alfred W.

    1985-01-01

    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 throughout the assembly.

  2. 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

  3. Synchrotron Tune Adjustment by Longitudinal Motion of Quadrupoles

    NASA Astrophysics Data System (ADS)

    Bertsche, K. J.

    1996-05-01

    Adjustment of the tune of a synchrotron is generally accomplished by globally varying the strength of quadrupoles, either in the main quadrupole bus or in a set of dedicated trim quadrupoles distributed around the ring. An alternate scheme for tune control involves varying the strengths of quadrupoles only within a local insert, thereby adjusting the phase advance across this insert to create a "phase trombone." In a synchrotron built of permanent magnets, such as the proposed Fermilab Recycler Ring, tune adjustment may also be accomplished by constructing a phase trombone in which the longitudinal position rather than strength of a number of quadrupoles is adjusted. Design philosophies and performance for such phase trombones will be presented. *Operated by Universities Research Association, Inc., under contract with the US. Department of Energy.

  4. Double-photoionization of helium including quadrupole radiation effects

    SciTech Connect

    Colgan, James; Ludlow, J A; Lee, Teck - Ghee; Pindzola, M S; Robicheaux, F

    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.

  5. Rescuing the nonjet (NJ) azimuth quadrupole from the flow narrative

    NASA Astrophysics Data System (ADS)

    Trainor, Thomas A.

    2017-04-01

    According to the flow narrative commonly applied to high-energy nuclear collisions a cylindrical-quadrupole component of 1D azimuth angular correlations is conventionally denoted by quantity υ2 and interpreted to represent elliptic flow. Jet angular correlations may also contribute to υ2 data "nonflow" depending on the method used to calculate υ2, but 2D graphical methods are available to insure accurate separation. The nonjet (NJ) quadrupole has various properties inconsistent with a flow interpretation, including the observation that NJ quadrupole centrality variation in A-A collisions has no relation to strongly-varying jet modication ("jet quenching") in those collisions commonly attributed to jet interaction with a flowing dense medium. In this presentation I describe isolation of quadrupole spectra from pt-differential υ2(pt) data from the RHIC and LHC. I demonstrate that quadrupole spectra have characteristics very different from the single-particle spectra for most hadrons, that quadrupole spectra indicate a common boosted hadron source for a small minority of hadrons that "carry" the NJ quadrupole structure, that the narrow source-boost distribution is characteristic of an expanding thin cylindrical shell (strongly contradicting hydro descriptions), and that in the boost frame a single universal quadrupole spectrum (Lévy distribution) on transverse mass mt accurately describes data for several hadron species scaled according to their statistical-model abundances. The quadrupole spectrum shape changes very little from RHIC to LHC energies. Taken in combination those characteristics strongly suggest a unique nonflow (and nonjet) QCD mechanism for the NJ quadrupole conventionally represented by υ2.

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

    NASA Technical Reports Server (NTRS)

    Farassat, F.; Brentner, Kenneth S.

    1997-01-01

    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, we give a simple formulation based on the acoustic analogy that is valid for both subsonic and supersonic quadrupole noise prediction. Like the formulation of Brentner, the model is exact for an observer in the far field and in the rotor plane and is approximate elsewhere. We give the full analytic derivation of this formulation in the paper. We present the method of implementation on a computer for supersonic quadrupoles using marching cubes for constructing the influence surface (Sigma surface) of an observer space- time variable (x; t). We then present several examples of noise prediction 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 improves the prediction of the acoustic pressure signature. We show the equivalence 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.

  7. Microscopic description of quadrupole-octupole coupling in Sm and Gd isotopes with the Gogny energy density functional

    NASA Astrophysics Data System (ADS)

    Rodríguez-Guzmán, R.; Robledo, L. M.; Sarriguren, P.

    2012-09-01

    The interplay between the collective dynamics of the quadrupole and octupole deformation degree of freedom is discussed in a series of Sm and Gd isotopes both at the mean-field level and beyond, including parity symmetry restoration and configuration mixing. Physical properties such as negative-parity excitation energies and E1 and E3 transition probabilities are discussed and compared to experimental data. Other relevant intrinsic quantities such as dipole moments, ground-state quadrupole moments or correlation energies associated with symmetry restoration and configuration mixing are discussed. For the considered isotopes, the quadrupole-octupole coupling is found to be weak and most of the properties of negative-parity states can be described in terms of the octupole degree of freedom alone.

  8. 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.

  9. Quadrupole magnet for a rapid cycling synchrotron

    SciTech Connect

    Witte, H.; Berg, J. S.

    2015-05-03

    Rapid Cycling Synchrotrons (RCS) feature interleaved warm and cold dipole magnets; the field of the warm magnets is used to modulate the average bending field depending on the particle energy. It has been shown that RCS can be an attractive option for fast acceleration of particles, for example, muons, which decay quickly. In previous studies it was demonstrated that in principle warm dipole magnets can be designed which can provide the required ramp rates, which are equivalent to frequencies of about 1 kHz. To reduce the losses it is beneficial to employ two separate materials for the yoke; it was also shown that by employing an optimized excitation coil geometry the eddy current losses are acceptable. In this paper we show that the same principles can be applied to quadrupole magnets targeting 30 T/m with a repetition rate of 1kHz and good field quality.

  10. 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.

  11. 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.

  12. 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.

  13. Atomic Quadrupole Moment Measurement Using Dynamic Decoupling.

    PubMed

    Shaniv, R; Akerman, N; Ozeri, R

    2016-04-08

    We present a method that uses dynamic decoupling of a multilevel quantum probe to distinguish small frequency shifts that depend on m_{j}^{2}, where m_{j}^{2} is the angular momentum of level |j⟩ along the quantization axis, from large noisy shifts that are linear in m_{j}, such as those due to magnetic field noise. Using this method we measured the electric-quadrupole moment of the 4D_{5/2} level in ^{88}Sr^{+} to be 2.973_{-0.033}^{+0.026}ea_{0}^{2}. Our measurement improves the uncertainty of this value by an order of magnitude and thus helps mitigate an important systematic uncertainty in ^{88}Sr^{+} based optical atomic clocks and verifies complicated many-body quantum calculations.

  14. Hybrid high gradient permanent magnet quadrupole

    NASA Astrophysics Data System (ADS)

    N'gotta, P.; Le Bec, G.; Chavanne, J.

    2016-12-01

    This paper presents an innovative compact permanent magnet quadrupole with a strong gradient for potential use in future light source lattices. Its magnetic structure includes simple mechanical parts, rectangular permanent magnet blocks and soft iron poles. It has a wide aperture in the horizontal plane to accommodate an x-ray beam port, a common constraint in storage ring-based light sources. This specificity introduces field quality deterioration because of the resulting truncation of the poles; a suitable field quality can be restored with an optimized pole shape. A 82 T /m prototype with a bore radius of 12 mm and a 10 mm vertical gap between poles has been constructed and magnetically characterized. Gradient inhomogeneities better than 10-3 in the good field region were obtained after the installation of special shims.

  15. 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.

  16. Development of Superconducting Focusing Quadrupoles for Heavy Ion Drivers

    SciTech Connect

    Martovetsky, N; Manahan, R; Lietzke, A F

    2001-09-10

    Heavy Ion Fusion (HIF) is exploring a promising path to a practical inertial-confinement fusion reactor. The associated heavy ion driver will require a large number of focusing quadrupole magnets. A concept for a superconducting quadrupole array, using many simple racetrack coils, was developed at LLNL. Two, single-bore quadrupole prototypes of the same design, with distinctly different conductor, were designed, built, and tested. Both prototypes reached their short sample currents with little or no training. Magnet design, and test results, are presented and discussed.

  17. Solid state proton imaging detected by quadrupole resonance.

    PubMed

    Perlo, J; Casanova, F; Robert, H; Pusiol, D J

    2001-06-01

    A double resonance method for imaging of solid materials containing quadrupole nuclei via the coupled protons is reported. The technique uses a static field gradient to encode the position on the protons and the method of double resonance spin-echo to detect the occurrence of proton resonances by affecting the zero-field echo signal from the quadrupole system. The double resonance imaging method offers the advantages of higher spatial resolution and straightforward image reconstruction for powder samples compared with rotating-frame and Zeeman-perturbated nuclear quadrupole resonance encoding techniques. Copyright 2001 Academic Press.

  18. Acoustic monopoles, dipoles, and quadrupoles: An experiment revisited

    NASA Astrophysics Data System (ADS)

    Russell, Daniel A.; Titlow, Joseph P.; Bemmen, Ya-Juan

    1999-08-01

    A simple and inexpensive demonstration of acoustic monopole, dipole, and quadrupole sources utilizes four 4-in. boxed loudspeakers and a homemade switch box. The switch box allows the speakers to be driven in any combination of phase relationships. Placing the speakers on a rotating stool allows students to measure directivity patterns for monopole, dipole, and quadrupole speaker combinations. Stacking the speakers in a square, all facing the same direction, allows students to aurally compare the frequency and amplitude dependence of sound radiation from monopoles, dipoles, and quadrupoles.

  19. Emission of nuclear quadrupole resonance from polycrystalline hexamethylenetetramine.

    PubMed

    Ota, G; Itozaki, H

    2008-03-01

    The angular dependence of the nuclear quadrupole resonance (NQR) signal intensity emitted from polycrystalline hexamethylenetetramine has been analytically investigated for all directions for non-contact detection of chemicals by nuclear quadrupole resonance. The field pattern of the NQR signal from a column sample was measured. The emitted patterns were the same as that from a united single magnetic dipole, which fitted well to the estimation based on quadrupole principle axis system. This result is helpful to design an antenna for NQR remote detection.

  20. Characterization of the ELIMED prototype permanent magnet quadrupole system

    NASA Astrophysics Data System (ADS)

    Russo, A. D.; Schillaci, F.; Pommarel, L.; Romano, F.; Amato, A.; Amico, A. G.; Calanna, A.; Cirrone, G. A. P.; Costa, M.; Cuttone, G.; Amato, C.; De Luca, G.; Flacco, F. A.; Gallo, G.; Giove, D.; Grmek, A.; La Rosa, G.; Leanza, R.; Maggiore, M.; Malka, V.; Milluzzo, G.; Petringa, G.; Pipek, J.; Scuderi, V.; Vauzour, B.; Zappalà, E.

    2017-01-01

    The system described in this work is meant to be a prototype of a more performing one that will be installed at ELI-Beamlines in Prague for the collection of ions produced after the interaction Laser-target, [1]. It has been realized by the researchers of INFN-LNS (Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare) and SIGMAPHI, a French company, using a system of Permanent Magnet Quadrupoles (PMQs), [2]. The final system that will be installed in Prague is designed for protons and carbons up to 60 MeV/u, around 10 times more than the energies involved in the present work. The prototype, shown in this work, has been tested in collaboration with the SAPHIR experimental facility group at LOA (Laboratoire d'Optique Appliqueé) in Paris using a 200 TW Ti:Sapphire laser system. The purpose of this work is to validate the design and the performances of this large and compact bore system and to characterize the beam produced after the interaction laser-target and its features. Moreover, the optics simulations have been compared with a real beam shape on a GAFChromic film. The procedure used during the experimental campaign and the most relevant results are reported here demonstrating a good agreement with the simulations and a good control on the beam optics.

  1. Beam based alignment of C-shaped quadrupole magnets

    SciTech Connect

    Portmann, G.; Robin, D.

    1998-06-01

    Many storage rings have implemented a method of finding the positional offset between the electrical center of the beam position monitors (BPM) and the magnetic center of the adjacent quadrupole magnets. The algorithm for accomplishing this is usually based on modulating the current in the quadrupole magnet and finding the beam position that minimizes the orbit perturbation. When the quadrupole magnet is C-shaped, as it is for many light sources, the modulation method can produce an erroneous measurement of the magnetic center in the horizontal plane. When the current in a C-shaped quadrupole is changed, there is an additional dipole component in the vertical field. Due to nonlinearities in the hysteresis cycle of the C-magnet geometry, the beam-based alignment technique at the Advanced Light Source (ALS) deviated horizontally by .5 mm from the actual magnetic center. By modifying the technique, the offsets were measured to an accuracy of better than 50 {micro}m.

  2. PRINCIPLE OF SKEW QUADRUPOLE MODULATION TO MEASURE BETATRON COUPLING.

    SciTech Connect

    LUO.Y.PILAT,F.ROSER,T.ET AL.

    2004-07-05

    The measurement of the residual betatron coupling via skew quadrupole modulation is a new diagnostics technique that has been developed and tested at the Relativistic Heavy Ion Collider (RHIC) as a very promising method for the linear decoupling on the ramp. By modulating the strengths of different skew quadrupole families the two eigentunes are precisely measured with the phase lock loop system. The projections of the residual coupling coefficient onto the skew quadrupole coupling modulation directions are determined. The residual linear coupling could be corrected according to the measurement. An analytical solution for skew quadrupole modulation based on Hamiltonian perturbation approximation is given, and simulation code using smooth accelerator model is also developed. Some issues concerning the practical applications of this technique are discussed.

  3. 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.

  4. Quadrupole electromagnetic radiation of an oscillating charged droplet

    NASA Astrophysics Data System (ADS)

    Grigor'ev, A. I.; Kolbneva, N. Yu.; Shiryaeva, S. O.

    2017-06-01

    Analytical calculations using the first order of smallness with respect to dimensionless amplitude of oscillations show that the intensity of electromagnetic radiation of a charged droplet is determined by time-dependent quadrupole moment.

  5. 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.

  6. 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.

  7. Nuclear spin squeezing via electric quadrupole interaction

    NASA Astrophysics Data System (ADS)

    Aksu Korkmaz, Yaǧmur; Bulutay, Ceyhun

    2016-01-01

    Control over nuclear-spin fluctuations is essential for processes that rely on preserving the quantum state of an embedded system. For this purpose, squeezing is a viable alternative, so far that has not been properly exploited for the nuclear spins. Of particular relevance in solids is the electric quadrupole interaction (QI), which operates on nuclei having spin higher than 1/2. In its general form, QI involves an electric-field gradient (EFG) biaxiality term. Here, we show that as this EFG biaxiality increases, it enables continuous tuning of single-particle squeezing from the one-axis twisting to the two-axis countertwisting limits. A detailed analysis of QI squeezing is provided, exhibiting the intricate consequences of EFG biaxiality. The initial states over the Bloch sphere are mapped out to identify those favorable for fast initial squeezing, or for prolonged squeezings. Furthermore, the evolution of squeezing in the presence of a phase-damping channel and an external magnetic field are investigated. We observe that dephasing drives toward an antisqueezed terminal state, the degree of which increases with the spin angular momentum. Finally, QI squeezing in the limiting case of a two-dimensional EFG with a perpendicular magnetic field is discussed, which is of importance for two-dimensional materials, and the associated beat patterns in squeezing are revealed.

  8. 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.

  9. Development of electrostatic quadrupoles for heavy ion fusion

    SciTech Connect

    Faltens, A.; Seidl, P.

    1996-03-01

    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 break-down 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 trade-offs between very large numbers of small channels and a smaller number of large channels, and the dependence of the choice on the voltage break-down 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.

  10. Dynamics of a charged drop in a quadrupole electric field

    NASA Astrophysics Data System (ADS)

    Das, Sudip; Mayya, Y. S.; Thaokar, Rochish

    2015-07-01

    Quadrupole electric fields are commonly employed for confining charged conducting drops in Paul traps for studying Rayleigh instability characteristics. We investigate the effect of these fields on the deformation and stability characteristics of a charged liquid drop, using the axisymmetric boundary integral method (BIM). Different combinations of the amount of charge and strength of the electric field give rise to different equilibrium shapes. Interestingly, unlike in the case of uniform fields, stable oblate equilibrium drop shapes are sustained in quadrupole fields. In a positive endcap configuration of the quadrupole setup a drop carrying a small negative charge displays a transition from oblate to prolate as the field strength increases. On the other hand, for the case of a highly charged drop, a shift in the Rayleigh critical charge is observed in the presence of a weak quadrupole field. The Rayleigh instability displays imperfect transcritical bifurcation characteristics with respect to imposed prolate and oblate perturbations. Results are of significance in i) interpreting deformation and the Rayleigh stability effects using Paul traps with quadrupole fields, ii) designing more efficient quadrupole-field-based technologies for emulsification of water in oil.

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

    PubMed

    Peng, Shixiang; Chen, Jia; Ren, Haitao; Zhao, Jie; Xu, Yuan; Zhang, Tao; Zhang, Ailing; Xia, Wenlong; Gao, Shuli; Wang, Zhi; Luo, Yuting; Guo, Zhiyu; Chen, Jia'er

    2014-02-01

    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 π mm mrad and the fraction of He+ is about 99%.

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

    SciTech Connect

    Peng, Shixiang Chen, Jia; Ren, Haitao; Zhao, Jie; Xu, Yuan; Zhang, Tao; Xia, Wenlong; Gao, Shuli; Wang, Zhi; Luo, Yuting; Guo, Zhiyu; Zhang, Ailing; Chen, Jia'er

    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 π mm mrad and the fraction of He+ is about 99%.

  13. Global analysis of quadrupole shape invariants based on covariant energy density functionals

    NASA Astrophysics Data System (ADS)

    Quan, S.; Chen, Q.; Li, Z. P.; Nikšić, T.; Vretenar, D.

    2017-05-01

    Background: The coexistence of different geometric shapes at low energies presents a universal structure phenomenon that occurs over the entire chart of nuclides. Studies of the shape coexistence are important for understanding the microscopic origin of collectivity and modifications of shell structure in exotic nuclei far from stability. Purpose: The aim of this work is to provide a systematic analysis of characteristic signatures of coexisting nuclear shapes in different mass regions, using a global self-consistent theoretical method based on universal energy density functionals and the quadrupole collective model. Method: The low-energy excitation spectrum and quadrupole shape invariants of the two lowest 0+ states of even-even nuclei are obtained as solutions of a five-dimensional collective Hamiltonian (5DCH) model, with parameters determined by constrained self-consistent mean-field calculations based on the relativistic energy density functional PC-PK1, and a finite-range pairing interaction. Results: The theoretical excitation energies of the states, 21+,41+,02+,22+,23+, as well as the B (E 2 ;01+→21+) values, are in very good agreement with the corresponding experimental values for 621 even-even nuclei. Quadrupole shape invariants have been implemented to investigate shape coexistence, and the distribution of possible shape-coexisting nuclei is consistent with results obtained in recent theoretical studies and available data. Conclusions: The present analysis has shown that, when based on a universal and consistent microscopic framework of nuclear density functionals, shape invariants provide distinct indicators and reliable predictions for the occurrence of low-energy coexisting shapes. This method is particularly useful for studies of shape coexistence in regions far from stability where few data are available.

  14. Electric Quadrupole and Magnetic Dipole Moments of Mirror Nuclei and Self-Conjugate Nuclei

    NASA Astrophysics Data System (ADS)

    Zickendraht, W.

    A transformation, which brings about the unification of the nuclear collective and single particle models, yields sumrules for the magnetic dipole moments and for the electric quadrupole moments of mirror nuclei. These sumrules are applied to cases, for which the numerical values of these moments are known.Translated AbstractElektrische Qadrupol- und Magnetische Dipolmomente von Spiegelkernen und Kernen mit N = ZMit Hilfe einer Transformation, die die Vereinigung von Kollektiv- und Schalenmodell liefert, lassen sich Summenregeln für die magnetischen Dipol- und die elektrischen Quadrupolmomente von Spiegelkernen ableiten. Diese Summenregeln werden auf Spiegelkerne angewandt, für die die numerischen Werte der Momente bekannt sind.

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

    SciTech Connect

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

    2011-12-15

    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.

  16. 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.

  17. Theoretical investigation of flute modes in a magnetic quadrupole

    SciTech Connect

    Wu, H.S.

    1988-01-01

    This research developed theories and conducted numerical investigations of electrostatic flute modes in a plasma confined in a magnetic quadrupole. Chapter I presents the discussion of relevant background. Chapter II contains a brief discussion of the basic flute-mode operator L{sub 0} for intermediate- and low-frequency regimes. Chapter III develops a simple theory for a flute mode with frequency between the electron and ion bounce frequencies in the uniform density and temperature regions of a magnetic quadrupole. The frequency is predicted to be inversely proportional to the wave number. Chapter IV describes the kinetic approach. Chapter V contains the derivation of an eigenvalue equation for electrostatic waves with frequencies below the ion frequency in the private flux region of a magnetic quadrupole. Chapter VI develops a theory for electrostatic waves with frequency below the ion bounce frequency in the shared flux region of a magnetic quadrupole. Chapter VII contains the derivation of a dispersion equation for flute modes with frequencies between the electron and ion bounce frequencies in a plasma confined to a magnetic quadrupole. Chapter VIII presents a summary of the research described.

  18. Theoretical investigation of flute modes in a magnetic quadrupole

    SciTech Connect

    Wu, H.S.

    1988-01-01

    The objective of this research is to develop theories and conduct numerical investigations of electrostatic flute modes in a plasma confined in magnetic quadrupole. Chapter I presents the discussion of relevant background. Chapter II contains a brief discussion of the basic flute-mode operator L{sub 0} for intermediate- and low frequency regimes. Chapter III develops a simple theory for a flute mode with frequency between the electron and ion bounce frequencies in the uniform density and temperature regions of a magnetic quadrupole. Chapter IV describes the kinetic approach. Chapter V contains the derivation of an eigenvalue equation for electrostatic waves with frequencies below the ion frequency in the private flux region of a magnetic quadrupole. Chapter VI develops a theory for electrostatic waves with frequency below the ion bounce frequency in the shared flux region of a magnetic quadrupole. Chapter VII contains the derivation of a dispersion equation for flute modes with frequencies between the electron and ion ounce frequencies in a plasma confined to a magnetic quadrupole. Two intermediate-frequency modes are predicted.

  19. Quadrupole contribution to the third-order optical activity spectroscopy

    NASA Astrophysics Data System (ADS)

    Choi, Jun-Ho; Cho, Minhaeng

    2007-07-01

    Time-resolved nonlinear optical activity measurement spectroscopy can be a useful tool for studying biomolecular and chemical reaction dynamics of chiral molecules. Only recently, the two-dimensional (2D) circularly polarized photon echo (CP-PE) spectroscopy of polypeptides and a photosynthetic light-harvesting complex were discussed, where the beam configuration was specifically controlled in such a way to eliminate the quadrupole contribution to the CP-PE signal. In this paper, we generalize the CP-PE spectroscopy by including the transition quadrupole contributions from peptide amide I vibrational transition and chlorophyll electronic transition. By using a density functional theory calculation method, the corresponding amide I vibrational and chlorophyll Qy electronic transition quadrupole tensor elements are determined. Amplitude of nonlinear optical transition pathway involving a quadrupole transition is found to be comparable to those of magnetic dipole terms for two different cases considered, i.e., dipeptides and photosynthetic antenna complex. However, due to the rotational averaging factors, the overall quadrupole contribution is an order of magnitude smaller than the magnetic dipole contribution. This suggests that the conventional 2D photon echo method and experimental scheme can be directly used to measure the 2D CP-PE signal from proteins and molecular complexes and that the 2D CP-PE signal is mainly dictated by the magnetic dipole contribution.

  20. Quadrupole contribution to the third-order optical activity spectroscopy.

    PubMed

    Choi, Jun-Ho; Cho, Minhaeng

    2007-07-14

    Time-resolved nonlinear optical activity measurement spectroscopy can be a useful tool for studying biomolecular and chemical reaction dynamics of chiral molecules. Only recently, the two-dimensional (2D) circularly polarized photon echo (CP-PE) spectroscopy of polypeptides and a photosynthetic light-harvesting complex were discussed, where the beam configuration was specifically controlled in such a way to eliminate the quadrupole contribution to the CP-PE signal. In this paper, we generalize the CP-PE spectroscopy by including the transition quadrupole contributions from peptide amide I vibrational transition and chlorophyll electronic transition. By using a density functional theory calculation method, the corresponding amide I vibrational and chlorophyll Q(y) electronic transition quadrupole tensor elements are determined. Amplitude of nonlinear optical transition pathway involving a quadrupole transition is found to be comparable to those of magnetic dipole terms for two different cases considered, i.e., dipeptides and photosynthetic antenna complex. However, due to the rotational averaging factors, the overall quadrupole contribution is an order of magnitude smaller than the magnetic dipole contribution. This suggests that the conventional 2D photon echo method and experimental scheme can be directly used to measure the 2D CP-PE signal from proteins and molecular complexes and that the 2D CP-PE signal is mainly dictated by the magnetic dipole contribution.

  1. Nuclear Quadrupole Resonance Study of Potassium - - Chloride.

    NASA Astrophysics Data System (ADS)

    Ramia, Maximo Elias

    Fast Fourier transform nuclear quadrupole resonance (NQR) was used to study the cubic antifluorite crystal potassium hexacloro-osmate, K(,2)OsCl(,6). The study of the ('35)Cl and ('37)Cl resonances were performed on three samples of K(,2)OsCl(,6), a powder sample, a powder sample recrystallized from D(,2)O and a single crystal sample. The studies were carried out in the temperature range 300 to 6K. A detailed study of the ('35)Cl and ('37)Cl NQR lineshapes, in the temperature range 70 to 300K, showed that the lineshapes reflect the strain fields produced by lattice dislocations and point defects. The temperature evolution of these strain fields give rise to a satellite line which previously was attributed to H('+) ion impurities present in the samples. A comprehensive study of the temperature evolution of the NQR spectrum in the vicinity of the phase transition revealed a drop of line intensity and the progressive appearance of an extra broad resonance component. Both effects are associated with the existence of precursor dynamic clusters at temperatures higher than T(,C). Qualitatively similar but quantitatively different behaviour was observed in the powder and single crystal samples. Although the precursor clusters are an intrinsic property of the phrase transition, their detailed dynamics is sample independent. A NQR study of the tetragonal phase showed that at the lowest temperature the ratio of line intensities is 2:1. The phase shift effect previously observed in the tetragonal phase of K(,2)ReCl(,6) was also observed in K(,2)OsCl(,6). The effect has been explained as an experimental artifact introduced by the truncation of the FID due to the spectrometer dead time. Spin-lattice relaxation measurements in the cubic phase show two component relaxation in the vicinity of T(,C). The behaviour is quantitatively different in the powder and single crystal samples. The short relaxation time is associated with dynamic clusters. Spin-lattice relaxation time

  2. 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.

  3. Study the most favorable shapes of electrostatic quadrupole doublet lenses

    NASA Astrophysics Data System (ADS)

    Hussein, O. A.; Sise, O.

    2017-02-01

    The optical properties of an electrostatic quadrupole doublet lens with two different electrode shapes were studied with the aid of computer simulation. The optimal electrode voltages of the electrostatic quadrupole lenses which give the stigmatic image in both planes simultaneously were found for both concave cylindrical electrode shape and plan electrode shape of the operation mode: parallel to point focusing. The effect of electrode shape on the image properties was investigated, and the aberration figures were studied. The results showed that under the same operation condition and the geometrical dimensions, the changing of the electrode shape of the electrostatic quadrupole doublet lenses lead to important differences in the optical properties of the lenses and the characteristics of the systems.

  4. Stability of an aqueous quadrupole micro-trap

    DOE PAGES

    Park, Jae Hyun; Krstić, Predrag S.

    2012-01-01

    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 couldmore » play of a role of a synthetic virtual nanopore for the 3rd generation of DNA sequencing technology.« less

  5. Dark energy reflections in the redshift-space quadrupole.

    PubMed

    Yamamoto, Kazuhiro; Bassett, Bruce A; Nishioka, Hiroaki

    2005-02-11

    We show that the redshift-space quadrupole will be a powerful tool for constraining dark energy even if the baryon oscillations are missing from the monopole power spectrum and bias is scale and time dependent. We calculate the accuracy with which next-generation galaxy surveys such as KAOS will measure the quadrupole power spectrum, which gives the leading anisotropies in the power spectrum in redshift space due to linear velocity, and the so-called "Finger of God" and Alcock-Paczynski effects. Combining the monopole and quadrupole power spectra, in the complete absence of baryon oscillations (Omegab=0), leads to a roughly 500% improvement in constraints on dark energy compared with those from the monopole spectrum alone.

  6. Mechanical Design of a Second Generation LHC IR Quadrupole

    SciTech Connect

    Caspi, S.; Bartlett, S.E.; Dietderich, D.R.; Ferracin, P.; Gourlay, S.A.; Hafalia, R.R.; Hannaford, C.R.; Lietzke, A.F.; McInturff,A.D.; Sabbi, G.; Scanlan, R.M.

    2003-11-10

    One of the proposed options to increase the LHC luminosity is the replacement of the existing inner triplets at the Interaction Regions with new low-beta larger aperture quadrupoles operating at the same gradient. Lawrence Berkeley National Laboratory (LBNL) is carrying out preliminary studies of a large-bore Nb{sub 3}Sn quadrupole. The mechanical design presents a support structure based on the use of keys and bladders without self-supporting collars. This technology has been proven effective in several successful common coil Nb{sub 3}Sn dipoles built at LBNL, and it is for the first time applied to a cos(2{var_theta}) design. In this paper we present a detailed analysis of the quadrupole mechanical behavior, demonstrating the possibility of delivering, through this method, well-controlled coil precompression during assembly, cool-down and excitation. The study has been performed with the finite element program ANSYS.

  7. Stability of an aqueous quadrupole micro-trap

    SciTech Connect

    Park, Jae Hyun; Krstić, Predrag S.

    2012-01-01

    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.

  8. Enhanced quadrupole effects for atoms in optical vortices.

    PubMed

    Lembessis, V E; Babiker, M

    2013-02-22

    We show that the normally weak optical quadrupole interaction in atoms is enhanced significantly when the atom interacts at near resonance with an optical vortex. In particular, the forces and torque acting on the atom are shown here to scale up with the square of the winding number l of the vortex. Because the integer l can be arranged to be large, this property allows for processes involving dipole-forbidden, but quadrupole-allowed, transitions in atoms, such as cesium and oxygen, to come into play. We show that the mechanical effects of vortex light on atoms involving translational and rotational motion as well as trapping should be significantly enhanced for quadrupole transitions and present novel features with useful implications for the emerging field of atomtronics.

  9. Removal of Axial Twist in RHIC Insertion Quadrupole Magnets

    NASA Astrophysics Data System (ADS)

    Cozzolino, J.; Anerella, M.; Jain, A.; Louie, W.; Muratore, P.

    1997-05-01

    The focusing triplets located on either side of the six interaction points of RHIC each consist of three 13cm aperture quadrupoles with magnetic lengths of 1.44m (Q1), 3.40m (Q2), and 2.10m (Q3). The field quality and alignment of these magnets are most critical to the performance of the accelerator. The maximum allowable axial twist of the cold mass, defined as the standard deviation in the quadrupole roll angle, is 0.5 mrad. This requirement has occasionally exceeded the capabilities of the assembly fixturing and the procedures used to complete the axial welding of the shell halves around the cold mass yoke. A corrective shell welding technique has been successfully employed to remove excessive axial twist of the 13cm quadrupoles. This ``custom straightening" method will be described along with the before and after mechanical inspection data. The magnetic results which confirm the untwisting procedure shall also be discussed.

  10. Effect of nuclear quadrupole moments on parity nonconservation in atoms

    NASA Astrophysics Data System (ADS)

    Flambaum, V. V.; Dzuba, V. A.; Harabati, C.

    2017-07-01

    Nuclei with spin I ≥1 have a weak quadrupole moment which leads to tensor contribution to the parity nonconserving interaction between nuclei and electrons. We calculate this contribution for atoms of current experiment interest Yb+, Fr, and Ra+. We have also performed order of magnitude estimates and found strong enhancement of the weak quadrupole effects due to the close levels of opposite parity in many lanthanoids (e.g., Nd, Gd, Dy, Ho, Er, Pr, Sm) and Ra. Another possibility is to measure the parity-nonconservation (PNC) transitions between the hyperfine components of the ground state of Bi. Since nuclear weak charge is dominated by neutrons this opens a way of measuring quadrupole moments of neutron distribution in nuclei.

  11. 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

    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.

  12. 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.

  13. An introduction to quadrupole-time-of-flight mass spectrometry.

    PubMed

    Chernushevich, I V; Loboda, A V; Thomson, B A

    2001-08-01

    A brief introduction is presented to the basic principles and application of a quadrupole-time-of-flight (TOF) tandem mass spectrometer. The main features of reflecting TOF instruments with orthogonal injection of ions are discussed. Their operation and performance are compared with those of triple quadrupoles with electrospray ionization and matrix-assisted laser desorption/ionization (MALDI) TOF mass spectrometers. Examples and recommendations are provided for all major operational modes: mass spectrometry (MS) and tandem MS (MS/MS), precursor ion scans and studies of non-covalent complexes. Basic algorithms for liquid chromatography/MS/MS automation are discussed and illustrated by two applications.

  14. Observation of Excited Quadrupole-Bound States in Cold Anions

    NASA Astrophysics Data System (ADS)

    Zhu, Guo-Zhu; Liu, Yuan; Wang, Lai-Sheng

    2017-07-01

    We report the first observation of an excited quadrupole-bound state (QBS) in an anion. High-resolution photoelectron imaging of cryogenically cooled 4-cyanophenoxide (4 CP- ) anions yields an electron detachment threshold of 24 927 cm-1 . The photodetachment spectrum reveals a resonant transition 20 cm-1 below the detachment threshold, which is attributed to an excited QBS of 4 CP- because neutral 4CP has a large quadrupole moment with a negligible dipole moment. The QBS is confirmed by observation of seventeen above-threshold resonances due to autodetachment from vibrational levels of the QBS.

  15. Conceptual design of a quadrupole magnet for eRHIC

    SciTech Connect

    Witte, H.; Berg, J. S.

    2015-05-03

    eRHIC is a proposed upgrade to the existing Relativistic Heavy Ion Collider (RHIC) hadron facility at Brookhaven National Laboratory, which would allow collisions of up to 21 GeV polarized electrons with a variety of species from the existing RHIC accelerator. eRHIC employs an Energy Recovery Linac (ERL) and an FFAG lattice for the arcs. The arcs require open-midplane quadrupole magnets of up to 30 T/m gradient of good field quality. In this paper we explore initial quadrupole magnet design concepts based on permanent magnetic material which allow to modify the gradient during operation.

  16. Simulation of nuclear quadrupole resonance for sensor probe optimization.

    PubMed

    Shinohara, Junichiro; Sato-Akaba, Hideo; Itozaki, Hideo

    2012-01-01

    A simulation method to estimate the detection efficiency of nuclear quadrupole resonance (NQR) was proposed for optimizing a sensing probe operating at radio frequencies (RFs). It first calculates the transmitted magnetic field from the probe coil to the target sample. The nuclei make quadrupole resonance by it. We considered this nonlinear reaction to estimate NQR emission by the nuclei. Then the received NQR signal intensity from the sample at the probe coil. We calculated the efficiency by testing two different probe types (solenoid and gradiometer) and by changing the relative positions of the probe and sample. The simulation results were in good agreement with the experimental results.

  17. 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%.

  18. Phase and Radial Motion in a Transverse Electric Quadrupole - Manufacturing

    SciTech Connect

    Billen, James; Crandall, Ken; Young, Lloyd

    2010-06-25

    ParmteqM comprises a group of codes (PARMTEQ, RFQUICK, CURLI, PARI, PARMTEQM, READVG and VANES) that are used to design high-performance radio-frequency quadrupole (RFQ) linacs. PARMTEQ is an acronym for "Phase and Radial Motion in a Transverse Electric Quadrupole". These codes are necessary to design the RFQ vane profile and analyze the beam performance including the effects of higher order multipole field components and image charges. Multi-particle simulations are supported in Version 3. PARMTEQM, VANES and READVG specifically provide manufacturing support to generate CNC machining instructions for the fabrication of vane profiles.

  19. Low-frequency quadrupole impedance of undulators and wigglers

    NASA Astrophysics Data System (ADS)

    Blednykh, A.; Bassi, G.; Hidaka, Y.; Smaluk, V.; Stupakov, G.

    2016-10-01

    An analytical expression of the low-frequency quadrupole impedance for undulators and wigglers is derived and benchmarked against beam-based impedance measurements done at the 3 GeV NSLS-II storage ring. The adopted theoretical model, valid for an arbitrary number of electromagnetic layers with parallel geometry, allows to calculate the quadrupole impedance for arbitrary values of the magnetic permeability μr . In the comparison of the analytical results with the measurements for variable magnet gaps, two limit cases of the permeability have been studied: the case of perfect magnets (μr→∞ ), and the case in which the magnets are fully saturated (μr=1 ).

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

    SciTech Connect

    Auerbach, N. Dmitriev, V. F. Flambaum, V. V. Lisetskiy, A. Sen'kov, R. A. Zelevinsky, V. G.

    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.

  1. g-factor and quadrupole moment of the 21/2- isomeric state in 131La: Signature for a weakly-deformed magnetic rotational band head

    NASA Astrophysics Data System (ADS)

    Kaur, Jasmeet; Bansal, Neeraj; Bhati, A. K.; Kumar, R.; Sharma, Vijay R.; Kapoor, K.; Kumar, V.; Kaur, Navneet

    2017-02-01

    The g-factor and the static quadrupole moment of a magnetic rotational band head 21/2- at 2121 keV in 131La have been determined by means of the time-differential perturbed angular distribution technique. The measured value of the g-factor, + 1.060 (4), is in agreement with the theoretical value for a three quasi-proton, π3 {11/2- [ 505 ] ⊗5/2+ [ 422 ] ⊗5/2+ [ 413 ] } Nilsson configuration assignment. The observed spectroscopic quadrupole moment ratio, Qs (21/2- ,131 La)/Qs (19/2- ,137 La) = 0.457 (4), supports the collective oblate shape (γ ∼ - 60 °) with quadrupole deformation β2 < 0.07. The half-life of the 21/2- state, 37.2(1) ns, is re-measured with better accuracy.

  2. Metabolite Profile of Salidroside in Rats by Ultraperformance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry and High-Performance Liquid Chromatography Coupled with Quadrupole-Linear Ion Trap Mass Spectrometry.

    PubMed

    Hu, Zhiwei; Wang, Ziming; Liu, Yong; Wu, Yan; Han, Xuejiao; Zheng, Jian; Yan, Xiufeng; Wang, Yang

    2015-10-21

    In the present work, the salidroside metabolite profile in rat urine was investigated, and subsequently the metabolic pathways of salidroside were proposed. After administrations of salidroside at an oral dose of 100 or 500 mg/kg, rat urine samples were collected and pretreated with methanol to precipitate the proteins. The pretreated samples were analyzed by an Acquity ultraperformance liquid chromatography (UPLC) coupled with an HSS T3 column and detected by quadrupole time-of-flight mass spectrometry (Q-TOF-MS) or high-performance liquid chromatography coupled with hybrid triple-quadrupole linear ion trap mass spectrometry (HPLC/Q-trap-MS). A total of eight metabolites were detected and identified on the basis of the characteristics of their protonated ions in the urine samples. The results elucidated that salidroside was metabolized via glucuronidation, sulfation, deglycosylation, hydroxylation, methylation, and dehydroxylation pathways in vivo.

  3. Large energy-spread beam diagnostics through quadrupole scans

    SciTech Connect

    Frederico, Joel; Adli, Erik; Hogan, Mark; Raubenheimer, Tor

    2012-12-21

    The Facility for Advanced Accelerator and Experimental Tests (FACET) is a new user facility at the SLAC National Accelerator Laboratory, servicing next-generation accelerator experiments. The 1.5% RMS energy spread of the FACET beam causes large chromatic aberrations in optics. These aberrations necessitate updated quadrupole scan fits to remain accurate.

  4. Large energy-spread beam diagnostics through quadrupole scans

    SciTech Connect

    Frederico, Joel; Adli, Erik; Hogan, Mark; Raubenheimer, Tor

    2013-01-01

    The Facility for Advanced Accelerator and Experimental Tests (FACET) is a new user facility at the SLAC National Accelerator Laboratory, servicing next-generation accelerator experiments. The 1.5% RMS energy spread of the FACET beam causes large chromatic aberrations in optics. These aberrations necessitate updated quadrupole scan fits to remain accurate.

  5. LARP Long Quadrupole: A "Long" Step Toward an LHC

    ScienceCinema

    Giorgio Ambrosio

    2016-07-12

    The beginning of the development of Nb3Sn magnets for particle accelerators goes back to the 1960’s. But only very recently has this development begun to face the challenges of fabricating Nb3Sn magnets which can meet the requirements of modern particle accelerators. LARP (the LHC Accelerator Research Program) is leading this effort focusing on long models of the Interaction Region quadrupoles for a possible luminosity upgrade of the Large Hadron Collider. A major milestone in this development is to test, by the end of 2009, 4m-long quadrupole models, which will be the first Nb3Sn accelerator-type magnets approaching the length of real accelerator magnets. The Long Quadrupoles (LQ) are “Proof-of-Principle” magnets which are to demonstrate that Nb3Sn technology is sufficiently mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, under development at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. Several challenges must be addressed for the successful fabrication of long Nb3Sn coils and magnets. These challenges and the solutions adopted will be presented together with the main features of the LQ magnets. Several R&D lines are participating to this effort and their contributions will be also presented.

  6. A LIGA Fabricated Quadrupole Array for Mass Spectroscopy

    NASA Technical Reports Server (NTRS)

    Jackson, K.; Wiberg, D. V.; Hecht, M. H.; Orient, O. J.; Chutjian, A.; Yee, K.; Fuerstenau, S.; Brennen, R. A.; Hruby, J.; Bonivert, W.

    1997-01-01

    A linear array of nine quadrupoles was fabricated using the LIGA process. Pole heights ranging from 1 to 3 mm were fabricated using synchrotron X-ray exposures to form free standing polymethylmethacrylate (PMMA) molds into which copper, gold or nickel were electroplated.

  7. Driving a quadrupole mass spectrometer via an isolating stage

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Aalami, Dean (Inventor); Darrach, Murray (Inventor); Orient, Otto (Inventor)

    2002-01-01

    Driving a quadrupole mass spectrometer includes obtaining an air core transformer with a primary and a secondary, matching the secondary to the mass spectrometer, and driving the primary based on first and second voltage levels. Driving of the primary is via an isolating stage that minimizes low level drive signal coupling.

  8. A LIGA Fabricated Quadrupole Array for Mass Spectroscopy

    NASA Technical Reports Server (NTRS)

    Jackson, K.; Wiberg, D. V.; Hecht, M. H.; Orient, O. J.; Chutjian, A.; Yee, K.; Fuerstenau, S.; Brennen, R. A.; Hruby, J.; Bonivert, W.

    1997-01-01

    A linear array of nine quadrupoles was fabricated using the LIGA process. Pole heights ranging from 1 to 3 mm were fabricated using synchrotron X-ray exposures to form free standing polymethylmethacrylate (PMMA) molds into which copper, gold or nickel were electroplated.

  9. Magnetic field data on Fermilab Energy-Saver quadrupoles

    SciTech Connect

    Schmidt, E.E.; Brown, B.C.; Cooper, W.E.; Fisk, H.E.; Gross, D.A.; Hanft, R.; Ohnuma, S.; Turkot, F.T.

    1983-03-01

    The Fermilab Energy Saver/Doubler (Tevatron) accelerator contains 216 superconducting quadrupole magnets. Before installation in the Tevatron ring, these magnets plus an additional number of spares were extensively tested at the Fermilab Magnet Test Facility (MTF). Details on the results of the tests are presented here.

  10. LARP Long Quadrupole: A "Long" Step Toward an LHC

    SciTech Connect

    Giorgio Ambrosio

    2008-02-13

    The beginning of the development of Nb3Sn magnets for particle accelerators goes back to the 1960’s. But only very recently has this development begun to face the challenges of fabricating Nb3Sn magnets which can meet the requirements of modern particle accelerators. LARP (the LHC Accelerator Research Program) is leading this effort focusing on long models of the Interaction Region quadrupoles for a possible luminosity upgrade of the Large Hadron Collider. A major milestone in this development is to test, by the end of 2009, 4m-long quadrupole models, which will be the first Nb3Sn accelerator-type magnets approaching the length of real accelerator magnets. The Long Quadrupoles (LQ) are “Proof-of-Principle” magnets which are to demonstrate that Nb3Sn technology is sufficiently mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, under development at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. Several challenges must be addressed for the successful fabrication of long Nb3Sn coils and magnets. These challenges and the solutions adopted will be presented together with the main features of the LQ magnets. Several R&D lines are participating to this effort and their contributions will be also presented.

  11. Level lifetimes and quadrupole moments from Coulomb excitation in the Ba chain and the N = 80 isotones

    NASA Astrophysics Data System (ADS)

    Bauer, C.; Guastalla, G.; Leske, J.; Möller, O.; Möller, T.; Pakarinen, J.; Pietralla, N.; Rainovski, G.; Rapisarda, E.; Seweryniak, D.; Stahl, C.; Stegmann, R.; Wiederhold, J.; Zhu, S.

    2012-12-01

    The chain of Barium isotopes enables us to study experimentally the evolution of nuclear quadrupole collectivity from the shell closure at N = 82 towards neutron-deficient or neutron-rich deformed nuclei. The TU Darmstadt group has investigated several nuclei from stable 130,132Ba up to radioactive 140,142Ba with the projectile-Coulomb excitation technique including the use of the Doppler-shift attenuation method (DSAM). Lifetimes of quadrupole-collective states of 132Ba and 140Ba were obtained for the first time as well as the static electric quadrupole moments Q(21+) for 130,132Ba and 140,142Ba. The results are compared to Monte Carlo shell model and Beyond-Mean-Field calculations. The phenomenon of shell stabilization in the N = 80 isotones is further investigated by measurements of the B(E2;21+ → 01+) values of 140Nd and 142Sm and comparison to the quasi-particle phonon model and shell-model calculations.

  12. Targeted proteomic quantification on quadrupole-orbitrap mass spectrometer.

    PubMed

    Gallien, Sebastien; Duriez, Elodie; Crone, Catharina; Kellmann, Markus; Moehring, Thomas; Domon, Bruno

    2012-12-01

    There is an immediate need for improved methods to systematically and precisely quantify large sets of peptides in complex biological samples. To date protein quantification in biological samples has been routinely performed on triple quadrupole instruments operated in selected reaction monitoring mode (SRM), and two major challenges remain. Firstly, the number of peptides to be included in one survey experiment needs to be increased to routinely reach several hundreds, and secondly, the degree of selectivity should be improved so as to reliably discriminate the targeted analytes from background interferences. High resolution and accurate mass (HR/AM) analysis on the recently developed Q-Exactive mass spectrometer can potentially address these issues. This instrument presents a unique configuration: it is constituted of an orbitrap mass analyzer equipped with a quadrupole mass filter as the front-end for precursor ion mass selection. This configuration enables new quantitative methods based on HR/AM measurements, including targeted analysis in MS mode (single ion monitoring) and in MS/MS mode (parallel reaction monitoring). The ability of the quadrupole to select a restricted m/z range allows one to overcome the dynamic range limitations associated with trapping devices, and the MS/MS mode provides an additional stage of selectivity. When applied to targeted protein quantification in urine samples and benchmarked with the reference SRM technique, the quadrupole-orbitrap instrument exhibits similar or better performance in terms of selectivity, dynamic range, and sensitivity. This high performance is further enhanced by leveraging the multiplexing capability of the instrument to design novel acquisition methods and apply them to large targeted proteomic studies for the first time, as demonstrated on 770 tryptic yeast peptides analyzed in one 60-min experiment. The increased quality of quadrupole-orbitrap data has the potential to improve existing protein

  13. Nuclear magnetic and quadrupole resonance in metallic powders in the presence of strong quadrupole interaction: Rhenium metal

    SciTech Connect

    Dimitropoulos, C.; Maglione, M.; Borsa, F.

    1988-03-01

    The nuclear-magnetic-resonance and nuclear-quadrupole-resonance (NQR-NMR) spectra of /sup 187/Re and /sup 185/Re in a powder of rhenium metal were measured in the temperature range 5--10 K both in zero field and with an external magnetic field. The zero-field NQR spectrum is severely broadened by a nonuniform distribution of quadrupole interactions. The average quadrupole coupling frequencies measured at 5 K are, for the two isotopes, ..nu../sub Q/ = 39 +- 0.2 MHz (/sup 187/Re) and ..nu../sub Q/ = 40.8 +- 0.3 MHz (/sup 185/Re). The spectra obtained in the presence of an external magnetic field can be interpreted satisfactorily in terms of transitions among the eigenstates of the full Hamiltonian (Zeeman plus quadrupolar). Measurements of relaxation rates yield T/sub 1/T = 0.03 sK, indicating a relaxation mechanism driven by the hyperfine interaction with the conduction electrons. The feasibility of NQR-NMR studies in small metal particles in the presence of strong inhomogeneous quadrupole interactions is assessed

  14. Reexamining the nuclear structure of 154Gd in the dynamic pairing plus quadrupole model

    NASA Astrophysics Data System (ADS)

    Gupta, J. B.; Hamilton, J. H.

    2017-05-01

    In a previous study of the collective multiphonon bands in 154Gd, using the microscopic dynamic pairing plus quadrupole model, data for eight K bands were analyzed. In the last four decades, its decay scheme is significantly revised and the nuclear theory has undergone a significant change. Special focus is on new weak intensity transitions in several bands and on the reassigned levels in its decay scheme. The present study represents a detailed revised analysis of the collective even parity bands below 2.1 MeV. Also, a discussion is given on the nature of the Kπ=0+ excited bands, validity of band mixing approach, and of the assumption of shape coexistence of β band with ground band. Comparison is made with the X (5) analytical symmetry and the algebraic interacting boson model predictions. Discussion of the 2 n transfer reactions is given. The validity of the multiphonon view of the Kπ=4+ and 22+ bands is also studied.

  15. Diabatization based on the dipole and quadrupole: The DQ method

    NASA Astrophysics Data System (ADS)

    Hoyer, Chad E.; Xu, Xuefei; Ma, Dongxia; Gagliardi, Laura; Truhlar, Donald G.

    2014-09-01

    In this work, we present a method, called the DQ scheme (where D and Q stand for dipole and quadrupole, respectively), for transforming a set of adiabatic electronic states to diabatic states by using the dipole and quadrupole moments to determine the transformation coefficients. It is more broadly applicable than methods based only on the dipole moment; for example, it is not restricted to electron transfer reactions, and it works with any electronic structure method and for molecules with and without symmetry, and it is convenient in not requiring orbital transformations. We illustrate this method by prototype applications to two cases, LiH and phenol, for which we compare the results to those obtained by the fourfold-way diabatization scheme.

  16. 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.; Ogitsu, T.; Orris, D.; Page, T.; Peterson, T.; Rabehl, R.; Robotham, W.; Scanlan, R.; 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.

  17. Improved performance of a quadrupole based glow discharge mass spectrometer

    SciTech Connect

    Valiga, R.E.; Duckworth, D.C.; Smith, D.H.

    1995-12-31

    Glow discharge mass spectrometry (GDMS) has experienced most of its commercial success in trace multi-element analysis using sector-based mass spectrometry. In most cases, the mass resolution available with these instruments allows elements of interest to be analyzed, even in the presence of polyatomic interferences (e.g., ArC+, ArN+, ArO+). Because quadrupole mass filters have little more than unit resolution, background equivalent concentrations (BEC`s) for many elements can be quite high (1-100 ppm). Because of this, many have discounted quadrupole GDMS as a useful trace analysis technique. In this work, the authors have explored methods of reducing the polyatomic interferences.

  18. 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.

  19. Beta function measurement in the Tevatron using quadrupole gradient modulation

    SciTech Connect

    Jansson, A.; Lebrun, P.; Volk, J.T.; /Fermilab

    2005-05-01

    Early in Run2, there was an effort to compare the different emittance measurements in the Tevatron (flying wires and synchrotron light) and understand the origin of the observed differences. To measure the beta function at a few key locations near the instruments, air-core quadrupoles were installed. By modulating the gradient of these magnets and measuring the effect on the tune, the lattice parameters can be extracted. Initially, the results seem to disagree with other methods. At the time, the lattice was strongly coupled due to a skew component in the main dipoles, caused by sagging of the cryostat. After a large fraction of the superconducting magnets were shimmed to remove a strong skew quadrupole component, the results now agree with the theoretical values to within 20%.

  20. Quadrupole moments of wobbling excitations in 163Lu

    SciTech Connect

    Gorgen, A.; Clark, R.M.; Cromaz, M.; Fallon, P.; Hagemann, G.B.; Hubel, H.; Lee, I.Y.; Macchiavelli, A.O.; Sletten, G.; Ward, D.; Bengtsson, R.

    2004-01-01

    Lifetimes of states in the triaxial strongly deformed bands of {sup 163}Lu have been measured in a Gammasphere experiment using the Doppler-shift attenuation method. The bands are interpreted as wobbling-phonon excitations from the characteristic electromagnetic properties of the transitions connecting the bands. Quadrupole moments were extracted for the 0-phonon yrast band and, for the first time, for the 1-phonon wobbling band. The very similar results found for both bands suggest a similar intrinsic structure confirming the wobbling interpretation. While the in-band quadrupole moments for the bands show a decreasing trend towards higher spin, the strength of the inter-band transitions remains constant. Both features can be understood by a small increase in triaxiality towards higher spin. Such a change in triaxiality is also found in cranking calculations, to which the experimental results are compared.

  1. Homotopy analysis method to study a quadrupole mass filter.

    PubMed

    Seddighi Chaharborj, S; Seddighi Chahrborj, S; Sadat Kiai, S M; Abu Bakar, M R; Ziaeian, I; Gheisari, Y

    2012-04-01

    The homotopy analysis method (HAM) is applied to study the behavior of a hyperbolic rods of quadrupole mass filter and a sinusoidal potential form V(ac)  cos(Ωt). Numerical computation method of a 20th-order HAM is employed to compare the physical properties of the confined ions with fifth-order Runge-Kutta method. Also, comparison is made for the first stability region, the ion trajectories in real time, the polar plots, and the ion trajectory in x - y plan. The results show that the two methods are fairly similar; therefore, the HAM method has potential application to solve linear and nonlinear equations of the charge particle confinement in quadrupole field. Copyright © 2012 John Wiley & Sons, Ltd.

  2. ELECTRON TRAPPING IN WIGGLER AND QUADRUPOLE MAGNETS OF CESRTA

    SciTech Connect

    Wang, Lanfa; Huang, Xiaobiao; Pivi, Mauro; /SLAC

    2010-08-25

    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 the wiggler and quadrupole magnets using the 3D code CLOUDLAND. We found that electrons can be trapped with long lifetime in a quadrupole magnet due to the mirror field trapping mechanism and photoelectrons produced in the wiggler zero field zone have long lifetime due to their complicated trajectory.

  3. 3D simulations of an electrostatic quadrupole injector

    SciTech Connect

    Grote, D.P. |; Friedman, A.; Yu, S.

    1993-02-01

    Analysis of the dynamics of a space charge dominated beam in a lattice of electrostatic focusing structures requires a full three-dimensional conic that includes self-consistent space charge fields and the fields from the complex conductor shapes. The existing WARP3d code, a particle simulation code which has been developed for heavy-ion fusion (HIF) applications contains machinery for handling particles in three-dimensional fields. A successive overrelaxation field solver with subgrid-scale placement of boundaries for rounded surface and four-fold symmetry has been added to the code. The electrostatic quadrupole (ESQ) injector for the ILSE accelerator facility being planned at Lawrence Berkeley Laboratory is shown as an application. The issue of concern is possible emittance degradation because the focusing voltages are a significant fraction of the particles` energy and because there are significant nonlinear fields arising from the shapes of the quadrupole structures.

  4. Performance of An Adjustable Strength Permanent Magnet Quadrupole

    SciTech Connect

    Gottschalk, S.C.; DeHart, T.E.; Kangas, K.W.; Spencer, C.M.; 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.

  5. Diabatization based on the dipole and quadrupole: The DQ method

    SciTech Connect

    Hoyer, Chad E.; Xu, Xuefei; Ma, Dongxia; Gagliardi, Laura E-mail: truhlar@umn.edu; Truhlar, Donald G. E-mail: truhlar@umn.edu

    2014-09-21

    In this work, we present a method, called the DQ scheme (where D and Q stand for dipole and quadrupole, respectively), for transforming a set of adiabatic electronic states to diabatic states by using the dipole and quadrupole moments to determine the transformation coefficients. It is more broadly applicable than methods based only on the dipole moment; for example, it is not restricted to electron transfer reactions, and it works with any electronic structure method and for molecules with and without symmetry, and it is convenient in not requiring orbital transformations. We illustrate this method by prototype applications to two cases, LiH and phenol, for which we compare the results to those obtained by the fourfold-way diabatization scheme.

  6. A decoherence-free subspace in a charge quadrupole qubit

    NASA Astrophysics Data System (ADS)

    Friesen, Mark; Ghosh, Joydip; Eriksson, M. A.; Coppersmith, S. N.

    2017-06-01

    Quantum computing promises significant speed-up for certain types of computational problems. However, robust implementations of semiconducting qubits must overcome the effects of charge noise that currently limit coherence during gate operations. Here we describe a scheme for protecting solid-state qubits from uniform electric field fluctuations by generalizing the concept of a decoherence-free subspace for spins, and we propose a specific physical implementation: a quadrupole charge qubit formed in a triple quantum dot. The unique design of the quadrupole qubit enables a particularly simple pulse sequence for suppressing the effects of noise during gate operations. Simulations yield gate fidelities 10-1,000 times better than traditional charge qubits, depending on the magnitude of the environmental noise. Our results suggest that any qubit scheme employing Coulomb interactions (for example, encoded spin qubits or two-qubit gates) could benefit from such a quadrupolar design.

  7. Quadrupole association and dissociation of hydrogen in the early Universe

    NASA Astrophysics Data System (ADS)

    Forrey, Robert C.

    2016-10-01

    Radiative association and photodissociation rates are calculated for quadrupole transitions of H2. A complete set of bound and unbound states are included in a self-consistent master equation to obtain steady-state concentrations for a dilute system of hydrogen atoms and molecules. Phenomenological rate constants computed from the steady-state concentrations satisfy detailed balance for any combination of matter and radiation temperature. Simple formulas are derived for expressing the steady-state distributions in terms of equilibrium distributions. The rate constant for radiative association is found to be generally small for all temperature combinations. The photodissociation rate constant for quadrupole transitions is found to dominate the rate constants for other H2 photodestruction mechanisms for {T}{{R}} ≤slant 3000 K. Implications for the formation and destruction of H2 in the early Universe are discussed.

  8. Development and Test of TQC models, LARP Technological Quadrupole Magnets

    SciTech Connect

    Bossert, R.C.; Ambrosio, G.; Andreev, N.; Barzi, E.; Carcagno, R.; Feher, S.; Kashikhin, V.S.; Kashikhin, V.V.; Nobrega, F.; Novitski, I.; Orris, D.; Tartaglia, M.; Zlobin, A.V.; Caspi, S.; Dietderich, D.; Ferracin, P.; Hafalia, A.R.; Sabbi, G.

    2008-06-01

    In support of the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider (LHC) luminosity upgrade, two-layer quadrupole models (TQC and TQS) with 90mm aperture are being constructed at Fermilab and LBNL within the framework of the US LHC Accelerator Research Program (LARP). This paper describes the development and test of TQC01b, the second TQC model, and the experience during construction of TQE02 and TQC02, subsequent models in the series. ANSYS analysis of the mechanical structure, its underlying assumptions, and changes based on experience with TQC01 are presented and discussed. Construction experience, in-process measurements, and modifications to the assembly since TQC01 are described. The test results presented here include magnet strain and quench performance during training of TQC01b, as well as quench studies of current ramp rate dependence.

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

    DOEpatents

    Brodowski, John

    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.

  10. Microfabricated Quadrupole Ion Trap for Mass Spectrometer Applications

    SciTech Connect

    Pau, S.; Pai, C.S.; Low, Y.L.; Moxom, J.; Reilly, P.T.A.; Whitten, W.B.; Ramsey, J.M.

    2006-03-31

    An array of miniaturized cylindrical quadrupole ion traps, with a radius of 20 {mu}m, is fabricated using silicon micromachining using phosphorus doped polysilicon and silicon dioxide for the purpose of creating a mass spectrometer on a chip. We have operated the array for mass-selective ion ejection and mass analysis using Xe ions at a pressure of 10{sup -4} Torr. The scaling rules for the ion trap in relation to operating pressure, voltage, and frequency are examined.

  11. 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.

  12. Gravitational radiation quadrupole formula is valid for gravitationally interacting systems

    NASA Technical Reports Server (NTRS)

    Walker, M.; Will, C. M.

    1980-01-01

    An argument is presented for the validity of the quadrupole formula for gravitational radiation energy loss in the far field of nearly Newtonian (e.g., binary stellar) systems. This argument differs from earlier ones in that it determines beforehand the formal accuracy of approximation required to describe gravitationally self-interacting systems, uses the corresponding approximate equation of motion explicitly, and evaluates the appropriate asymptotic quantities by matching along the correct space-time light cones.

  13. Magnetic performance of new Fermilab high gradient quadrupoles

    SciTech Connect

    Hanft, R.; Brown, B.C.; Carson, J.A.; Gourlay, S.A.; Lamm, M.J.; McInturff, A.D.; Mokhtarani, A.; Riddiford, A.

    1991-05-01

    For the Fermilab Tevatron low beta insertions installed in 1990--1991 as part of a luminosity upgrade there were built approximately 35 superconducting cold iron quadrupoles utilizing a two layer cos 2{theta} coil geometry with 76 mm diameter aperature. The field harmonics and strengths of these magnets obtained by measurement at cryogenic conditions are presented. Evidence for a longitudinal periodic structure in the remnant field is shown. 6 refs., 2 figs., 3 tabs.

  14. Longitudinal capture in the radio-frequency-quadrupole structure

    SciTech Connect

    Inagaki, S.

    1980-03-01

    The radio-frequency-quadrupole (RFQ) linac structure not only can attain easily transverse focusing in the low-beta region, but also can obtain very high capture efficiency because of its low beta-lambda and low-particle rigidity. An optimization study of the zero space-charge longitudinal capture in an RFQ linac that yields configurations with large capture efficiency is described.

  15. MEASURING LOCAL GRADIENT AND SKEW QUADRUPOLE ERRORS IN RHIC IRS.

    SciTech Connect

    CARDONA,J.; PEGGS,S.; PILAT,R.; PTITSYN,V.

    2004-07-05

    The measurement of local linear errors at RHIC interaction regions using an ''action and phase'' analysis of difference orbits has already been presented. This paper evaluates the accuracy of this technique using difference orbits that were taken when known gradient errors and skew quadrupole errors were intentionally introduced. It also presents action and phase analysis of simulated orbits when controlled errors are intentionally placed in a RHIC simulation model.

  16. Integral Equation theory of a system of nematic quadrupoles

    NASA Astrophysics Data System (ADS)

    Mandal, Biplab kumar; Kumar, Anupam; Mishra, Pankaj

    2016-10-01

    We have studied a system of nematic quadrupoles interacting via inverse power potential of the form U ≈ (σ/r)5 (σ is the diameter of the particles and r is the separation between them), both in 3-dimension and 2-dimension. Pair correlation function has been calculated by solving Rogers-Young (RY) integral equation theory. Thermodynamic consistency has been obtained ensuring the equality of pressure calculated by virial and compressibility routes.

  17. Quadrupole Ion/Neutral Mass Spectrometer for Space Shuttle Applications.

    DTIC Science & Technology

    1986-04-07

    fCon linue on reverse if neeec’O ond ientify by block number) _ A Quadrupole Ion/Neutral Mass Spectrometer (QINMS) was developed for the fourth flight...The charging of spacecraft surfaces, Rev. Geophys. and Space Phys. 19:577-616. 16. Paul , W., Rheinhard, H. P., and von Zahn, U. (1958) Das elektrische...massenfilter als massenspektrometer und isotopentrenner, Z. Ph sik 152:143-182. Paul , W., and Steinwedel, H. (1953) Z. Naturforsch 8a:448. Paul , W

  18. 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.

  19. Transport of radioactive ion beams and related safety issues: The {sup 132}Sn{sup +} case study

    SciTech Connect

    Osswald, F. Bouquerel, E.; Boutin, D.; Dinkov, A.; Sellam, A.

    2014-12-15

    The transport of intense radioactive ion beam currents requires a careful design in order to limit the beam losses, the contamination and thus the dose rates. Some investigations based on numerical models and calculations have been performed in the framework of the SPIRAL 2 project to evaluate the performance of a low energy beam transport line located between the isotope separation on line (ISOL) production cell and the experiment areas. The paper presents the results of the transverse phase-space analysis, the beam losses assessment, the resulting contamination, and radioactivity levels. They show that reasonable beam transmission, emittance growth, and dose rates can be achieved considering the current standards.

  20. 2p1v states populated in 135Te from 9Be induced reactions with a 132Sn beam

    SciTech Connect

    Allmond, James M; Stuchbery, Andrew E; Brown, Alex; Beene, James R; Galindo-Uribarri, Alfredo {nmn}; Gross, Carl J; Liang, J Felix; Padilla-Rodal, Elizabeth; Radford, David C; Varner Jr, Robert L; Ayres, A.; Batchelder, J. C.; Bey, A.; Bingham, C. R.; Howard, Meredith E; Jones, K. L.; Manning, Brett M; Mueller, Paul Edward; Nesaraja, Caroline D; Pain, Steven D; Peters, William A; Ratkiewicz, Andrew J; Schmitt, Kyle; Shapira, Dan; Smith, Michael Scott; Stone, N. J.; Stracener, Daniel W; Yu, Chang-Hong

    2014-01-01

    Gamma-ray transitions in $^{134}$\\textrm{Te}, $^{135}$\\textrm{Te}, and $^{136}$\\textrm{Te} were measured from $^{9}$\\textrm{Be} induced reactions with a radioactive $^{132}$\\textrm{Sn} beam at a sub-Coulomb barrier energy of $3$~MeV per nucleon using particle-$\\gamma$ coincidence spectroscopy. The transitions were selected by gating on alpha-like particles in a \\textrm{CsI} detector following a combination of ($^{9}$\\textrm{Be},$\\alpha 1n$), ($^{9}$\\textrm{Be},$\\alpha 2n$), and ($^{9}$\\textrm{Be},$\\alpha 3n$) reactions. Distorted wave Born approximation calculations suggest little to no contribution from the ($^{9}$\\textrm{Be},$^{7}$\\textrm{He}), ($^{9}$\\textrm{Be},$^{6}$\\textrm{He}), and ($^{9}$\\textrm{Be},$^{5}$\\textrm{He}) direct reactions. Gamma-ray transitions from previously known $2^+\\otimes \

  1. Broad-Spectrum Drug Screening Using Liquid Chromatography-Hybrid Triple-Quadrupole Linear Ion Trap Mass Spectrometry.

    PubMed

    Stone, Judy

    2016-01-01

    Urine is processed with a simple C18 solid-phase extraction (SPE) and reconstituted in mobile phase. The liquid chromatography system (LC) injects 10 μL of extracted sample onto a reverse-phase LC column for gradient analysis with ammonium formate/acetonitrile mobile phases. Drugs in the column eluent become charged in the ion source using positive electrospray ionization (ESI). Pseudomolecular ions (M + H) are analyzed by a hybrid triple-quadrupole linear ion trap (QqQ and QqLIT) mass spectrometer using an SRM-IDA-EPI acquisition. An initial 125 compound selected ion monitoring (SRM) survey scan (triple quadrupole or QqQ mode) is processed by the information-dependent acquisition (IDA) algorithm. The IDA algorithm selects SRM signals from the survey scan with a peak height above the threshold (the three most abundant SRM signals above 1000 cps) to define precursor ions for subsequent dependent scanning. In the dependent QqLIT scan(s), selected precursor ion(s) are passed through the first quadrupole (Q1), fragmented with three different collision energies in the collision cell (Q2 or q), and product ions are collected in the third quadrupole (Q3), now operating as a linear ion trap (LIT). The ions are scanned out of the LIT in a mass dependent manner to produce a full-scan product ion spectrum (m/z 50-700) defined as an Enhanced (meaning acquired in LIT mode) Product Ion (EPI) spectrum (Mueller et al., Rapid Commun Mass Spectrom 19:1332-1338, 2005). Each EPI spectrum is linked to its precursor ion and to the associated SRM peak from the survey scan. EPI spectra are automatically searched against a 125 drug library of reference EPI spectra for identification. When the duty cycle is complete (one survey scan of 125 SRMs plus 0-3 dependent IDA-EPI scans) the mass spectrometer begins another survey scan of the 125 SRMs.

  2. CMB quadrupole suppression. II. The early fast roll stage

    NASA Astrophysics Data System (ADS)

    Boyanovsky, D.; de Vega, H. J.; Sanchez, N. G.

    2006-12-01

    Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established. Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and B-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of e-folds Ntot˜59, there is a 10% 20% suppression of the CMB quadrupole and about 2% 4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as 1/l2. The suppression is much smaller for Ntot>59, therefore if the observable suppression originates in the fast roll stage, there is the upper bound Ntot˜59.

  3. Position Stability Monitoring of THEthe LCLS Undulator Quadrupoles

    SciTech Connect

    Nuhn, Heinz Dieter; Gassner, Georg; Peters, Franz; /SLAC

    2012-03-26

    X-ray FELs demand that the positions of undulator components be stable to less than 1 {mu}m per day. Simultaneously, the undulator length increases significantly in order to saturate at x-ray wavelengths. To minimize the impact of the outside environment, the Linac Coherent Light Source (LCLS) undulator is placed underground, but reliable data about ground motion inside such a tunnel was not available in the required stability range during the planning phase. Therefore, a new position monitor system had been developed and installed with the LCLS undulator. This system is capable of measuring x, y, roll, pitch and yaw of each of the 33 undulator quadrupoles with respect to stretched wires. Instrument resolution is about 10 nm and instrument drift is negligible. Position data of individual quadrupoles can be correlated along the entire 132-m long undulator. The system has been under continuous operation since 2009. This report describes long term experiences with the running system and the observed positional stability of the undulator quadrupoles.

  4. Final 6D Muon Ionization Colling using Strong Focusing Quadrupoles

    SciTech Connect

    Hart, T. L.; Acosta, J. G.; Cremaldi, L. M.; Oliveros, S. J.; Summers, D. J.; Neuffer, D. V.

    2016-11-15

    Abstract Low emittance muon beam lines and muon colliders are potentially a rich source of BSM physics for future exper- imenters. A muon beam normalized emittance of ax,y,z = (280, 280, 1570)µm has been achieved in simulation with short solenoids and a betatron function of 3 cm. Here we use ICOOL and MAD-X to explore using a 400 MeV/c muon beam and strong focusing quadrupoles to achieve a normalized transverse emittance of 100 µm and complete 6D cooling. The low beta regions, as low as 5 mm, produced by the quadrupoles are occupied by dense, low Z absorbers, such as lithium hydride or beryllium, that cool the beam transversely. Equilibrium transverse emittance is linearly proportional to the transverse betatron function. Reverse emittance exchange with septa and/or wedges is then used to decrease transverse emittance from 100 to 25 µm at the expense of longitudinal emittance for a high energy lepton collider. Cooling challenges include chromaticity correction, ssband overlap, quadrupole acceptance, and staying in phase with RF.

  5. CMB quadrupole suppression. II. The early fast roll stage

    SciTech Connect

    Boyanovsky, D.; Vega, H. J. de; Sanchez, N. G.

    2006-12-15

    Within the effective field theory of inflation, an initialization of the classical dynamics of the inflaton with approximate equipartition between the kinetic and potential energy of the inflaton leads to a brief fast roll stage that precedes the slow roll regime. The fast roll stage leads to an attractive potential in the wave equations for the mode functions of curvature and tensor perturbations. The evolution of the inflationary perturbations is equivalent to the scattering by this potential and a useful dictionary between the scattering data and observables is established. Implementing methods from scattering theory we prove that this attractive potential leads to a suppression of the quadrupole moment for CMB and B-mode angular power spectra. The scale of the potential is determined by the Hubble parameter during slow roll. Within the effective field theory of inflation at the grand unification (GUT) energy scale we find that if inflation lasts a total number of e-folds N{sub tot}{approx}59, there is a 10%-20% suppression of the CMB quadrupole and about 2%-4% suppression of the tensor quadrupole. The suppression of higher multipoles is smaller, falling off as 1/l{sup 2}. The suppression is much smaller for N{sub tot}>59, therefore if the observable suppression originates in the fast roll stage, there is the upper bound N{sub tot}{approx}59.

  6. 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.

  7. Quadrupole Splitting Distribution of Fe2+ in Synthetic Trioctahedral Micas

    NASA Astrophysics Data System (ADS)

    Redhammer, G. J.; Amthauer, G.; Lottermoser, W.; Roth, G.

    2002-06-01

    About 80 different synthetic trioctahedral micas {K}[Fe2+ 3- x Me x ]4O10(OH)2 with Me = Ni2+, Mg2+, Co2+, Al3+ and Fe3+ have been synthesized by hydrothermal methods and subsequently investigated by 57Fe Mössbauer spectroscopy. Mössbauer spectra were refined in terms of a quadrupole splitting distribution (QSD) with at least 2 components for Fe2+ and additional components for Fe3+ on octahedral and tetrahedral positions. Three Fe2+ components have to be used in all samples containing distinct amounts of trivalent cations (Fe3+, Al3+). A rough positive correlation between the intensity of this third Fe2+ QSD component and the content of trivalent octahedral cations has been found. Substitution of Fe2+ by smaller divalent cations causes a distinct increase of ferrous quadrupole splitting. This suggests the remaining Fe2+O4(OH)2 octahedra to become more regular. This holds true for micas with and with composition of the tetrahedral sheet. In micas with Fe3+ in tetrahedral coordination there is a distinct increase of the quadrupole splitting of tetrahedral Fe3+ with decreasing size of the octahedral sheet. This can be explained by an increasing distortion of the second oxygen coordination sphere around tetrahedral Fe3+ due to increasing ditrigonal distortion of the tetrahedral sheet.

  8. Transverse beam emittance measurement using quadrupole variation at KIRAMS-430

    NASA Astrophysics Data System (ADS)

    An, Dong Hyun; Hahn, Garam; Park, Chawon

    2015-02-01

    In order to produce a 430 MeV/u carbon ion (12 C 6+) beam for medical therapy, the Korea Institute of Radiological & Medical Sciences (KIRAMS) has carried out the development of a superconducting isochronous cyclotron, the KIRAMS-430. At the extraction of the cyclotron, an Energy Selection System (ESS) is located to modulate the fixed beam energy and to drive the ion beam through High Energy Beam Transport (HEBT) into the treatment room. The beam emittance at the ion beamline is to be measured to provide information on designing a beam with high quality. The well-known quadrupole variation method was used to determine the feasibility of measuring the transverse beam emittance. The beam size measured at the beam profile monitor (BPM) is to be utilized and the transformation of beam by transfer matrix is to be applied being taken under various transport condition of varying quadrupole magnetic strength. Two different methods where beam optics are based on the linear matrix formalism and particle tracking with a 3-D magnetic field distribution obtained by using OPERA3D TOSCA, are applied to transport the beam. The fittings for the transformation parameters are used to estimate the transverse emittance and the twiss parameters at the entrance of the quadrupole in the ESS. Including several systematic studies, we conclude that within the uncertainty the estimated emittances are consistent with the ones calculated by using Monte Carlo simulations.

  9. Statistical thermodynamics of fluids with both dipole and quadrupole moments.

    PubMed

    Benavides, Ana L; Delgado, Francisco J García; Gámez, Francisco; Lago, Santiago; Garzón, Benito

    2011-06-21

    New Gibbs ensemble simulation data for a polar fluid modeled by a square-well potential plus dipole-dipole, dipole-quadrupole, and quadrupole-quadrupole interactions are presented. This simulation data is used in order to assess the applicability of the multipolar square-well perturbation theory [A. L. Benavides, Y. Guevara, and F. del Río, Physica A 202, 420 (1994)] to systems where more than one term in the multipole expansion is relevant. It is found that this theory is able to reproduce qualitatively well the vapor-liquid phase diagram for different multipolar moment strengths, corresponding to typical values of real molecules, except in the critical region. Hence, this theory is used to model the behavior of substances with multiple chemical bonds such as carbon monoxide and nitrous oxide and we found that with a suitable choice of the values of the intermolecular parameters, the vapor-liquid equilibrium of these species is adequately estimated. © 2011 American Institute of Physics

  10. Statistical thermodynamics of fluids with both dipole and quadrupole moments

    NASA Astrophysics Data System (ADS)

    Benavides, Ana L.; García Delgado, Francisco J.; Gámez, Francisco; Lago, Santiago; Garzón, Benito

    2011-06-01

    New Gibbs ensemble simulation data for a polar fluid modeled by a square-well potential plus dipole-dipole, dipole-quadrupole, and quadrupole-quadrupole interactions are presented. This simulation data is used in order to assess the applicability of the multipolar square-well perturbation theory [A. L. Benavides, Y. Guevara, and F. del Río, Physica A 202, 420 (1994), 10.1016/0378-4371(94)90469-3] to systems where more than one term in the multipole expansion is relevant. It is found that this theory is able to reproduce qualitatively well the vapor-liquid phase diagram for different multipolar moment strengths, corresponding to typical values of real molecules, except in the critical region. Hence, this theory is used to model the behavior of substances with multiple chemical bonds such as carbon monoxide and nitrous oxide and we found that with a suitable choice of the values of the intermolecular parameters, the vapor-liquid equilibrium of these species is adequately estimated.

  11. Well-proportioned universes suppress the cosmic microwave background quadrupole

    NASA Astrophysics Data System (ADS)

    Weeks, J.; Luminet, J.-P.; Riazuelo, A.; Lehoucq, R.

    2004-07-01

    A widespread myth asserts that all small universe models suppress the cosmic microwave background (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 lmin at which the CMB power spectrum l(l + 1) Cl/2π effectively begins; for cosmologically relevant models, lmin <= 3. 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 neighbourhood of lmin relative to the high-l 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 Cl 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.

  12. First tests of a superconducting RFQ (rf quadrupole) structure

    SciTech Connect

    Delayen, J.R.; Shepard, K.W.

    1990-01-01

    High surface electric fields have been obtained in the first tests of a superconducting rf quadrupole device. The rf quadrupole fields were generated between niobium vanes 6.5 cm in length, with an edge radius of 2 mm, and with a beam aperture of 6 mm diameter. In tests at 4.2 K, the 64 MHz device operated cw at peak surface electric fields of 128 MV/m. Virtually no electron loading was observed at fields below 100 MV/m. It was possible to operate at surface fields of 210 MV/m in pulses of 1 msec duration using a 2.5 kW rf source. For the vane geometry tested, more than 10 square centimeters of surface support a field greater than 90% of the peak field. The present result indicates that electric fields greater than 100 MV/m can be obtained over an appreciable area, sufficient for some accelerator applications. It also shows that superconducting rf technology may provide an extended range of options for rf quadrupole design.

  13. Quadrupole Magnetic Sorting of Porcine Islets of Langerhans

    PubMed Central

    Shenkman, Rustin M.; Chalmers, Jeffrey J.; Hering, Bernhard J.; Kirchhof, Nicole

    2009-01-01

    Islet transplantation is emerging as a treatment option for selected patients with type 1 diabetes. Inconsistent isolation, purification, and recovery of large numbers of high-quality islets remain substantial impediments to progress in the field. Removing islets as soon as they are liberated from the pancreas during digestion and circumventing the need for density gradient purification is likely to result in substantially increased viable islet yields by minimizing exposure to proteolytic enzymes, reactive oxygen intermediates, and mechanical stress associated with centrifugation. This study capitalized on the hypervascularity of islets compared with acinar tissue to explore their preferential enrichment with magnetic beads to enable immediate separation in a magnetic field utilizing a quadrupole magnetic sorting. The results demonstrate that (1) preferential enrichment of porcine islets is achievable, but homogeneous bead distribution within the pancreas is difficult to achieve with current protocols; (2) greater than 70% of islets in the dissociated pancreatic tissue were recovered by quadrupole magnetic sorting, but their purity was low; and (3) infused islets purified by density gradients and subsequently passed through quadrupole magnetic sorting had similar potency as uninfused islets. These results demonstrate proof of concept and define the steps for implementation of this technology in pig and human islet isolation. PMID:19505179

  14. Open questions on nuclear collective motion

    SciTech Connect

    Frauendorf, S.

    2016-07-07

    The status of the macroscopic and microscopic description of the collective quadrupole modes is reviewed, where limits due to non-adiabaticity and decoherence are exposed. The microscopic description of the yrast states in vibrator-like nuclei in the framework of the rotating mean field is presented.

  15. Characterization of the ELIMED Permanent Magnets Quadrupole system prototype with laser-driven proton beams

    NASA Astrophysics Data System (ADS)

    Schillaci, F.; Pommarel, L.; Romano, F.; Cuttone, G.; Costa, M.; Giove, D.; Maggiore, M.; Russo, A. D.; Scuderi, V.; Malka, V.; Vauzour, B.; Flacco, A.; Cirrone, G. A. P.

    2016-07-01

    Laser-based accelerators are gaining interest in recent years as an alternative to conventional machines [1]. In the actual ion acceleration scheme, energy and angular spread of the laser-driven beams are the main limiting factors for beam applications and different solutions for dedicated beam-transport lines have been proposed [2,3]. In this context a system of Permanent Magnet Quadrupoles (PMQs) has been realized [2] by INFN-LNS (Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare) researchers, in collaboration with SIGMAPHI company in France, to be used as a collection and pre-selection system for laser driven proton beams. This system is meant to be a prototype to a more performing one [3] to be installed at ELI-Beamlines for the collection of ions. The final system is designed for protons and carbons up to 60 MeV/u. In order to validate the design and the performances of this large bore, compact, high gradient magnetic system prototype an experimental campaign have been carried out, in collaboration with the group of the SAPHIR experimental facility at LOA (Laboratoire d'Optique Appliquée) in Paris using a 200 TW Ti:Sapphire laser system. During this campaign a deep study of the quadrupole system optics has been performed, comparing the results with the simulation codes used to determine the setup of the PMQ system and to track protons with realistic TNSA-like divergence and spectrum. Experimental and simulation results are good agreement, demonstrating the possibility to have a good control on the magnet optics. The procedure used during the experimental campaign and the most relevant results are reported here.

  16. 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.

  17. 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.

  18. Eccentric-fluted beam pipes to damp quadrupole higher-order modes

    NASA Astrophysics Data System (ADS)

    Sawamura, M.; Furuya, T.; Sakai, H.; Takahashi, T.; Umemori, K.; Shinoe, K.

    2010-02-01

    An eccentric-fluted beam pipe is proposed to damp quadrupole modes in a cavity. The eccentric flutes act as a mode converter from quadrupole to dipole. Optimizing the parameters of the eccentric-fluted beam pipe allows sufficient damping of both degenerate quadrupole modes. The external Q values of the eccentric-fluted beam pipe measured with a low power model cavity agree well with those calculated with the 3D electromagnetic field simulation code MAFIA.

  19. Design and construction of a radiation resistant quadrupole using metal oxide insulated CICC

    SciTech Connect

    Albert F. Zeller

    2012-12-28

    The construction of a engineering test model of a radiation resistant quadrupole is described. The cold-iron quadrupole uses coils fabricated from metal-oixide (synthetic spinel) insulated Cable-In-Conduit-Conductor (CICC). The superconductor is NbTi in a copper matrix. The quadrupole is designed to produce a pole-tip field of 2 T with an operating current of 7,000 A.

  20. 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.

  1. 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.

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

    SciTech Connect

    Feinberg, B.

    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.

  3. Ab initio calculation of the deuterium quadrupole coupling in liquid water

    NASA Astrophysics Data System (ADS)

    Eggenberger, Rolf; Gerber, Stefan; Huber, Hanspeter; Searles, Debra; Welker, Marc

    1992-10-01

    The quadrupole coupling constant and asymmetry parameter for the deuteron in liquid heavy water was determined using purely theoretical methods. Molecular-dynamics simulations with the ab initio potential-energy surface of Lie and Clementi were used to generate snapshots of the liquid. The electric-field gradient at the deuteron was then calculated for these configurations and averaged to obtain the liquid quadrupole coupling constant. At 300 K a quadrupole coupling constant of 256±5 kHz and an asymmetry parameter of 0.164±0.003 were obtained. The temperature dependence of the quadrupole coupling constant was investigated.

  4. CMB quadrupole suppression. I. Initial conditions of inflationary perturbations

    SciTech Connect

    Boyanovsky, D.; Vega, H. J. de; Sanchez, N. G.

    2006-12-15

    We investigate the issue of initial conditions of curvature and tensor perturbations at the beginning of slow roll inflation and their effect on the power spectra. Renormalizability and small backreaction constrain the high k behavior of the Bogoliubov coefficients that define these initial conditions. We introduce a transfer function D(k) which encodes the effect of generic initial conditions on the power spectra. The constraint from renormalizability and small backreaction entails that D(k)(less-or-similar sign){mu}{sup 2}/k{sup 2} for large k, implying that observable effects from initial conditions are more prominent in the low multipoles. This behavior affects the CMB quadrupole by the observed amount {approx}10%-20% when {mu} is of the order of the energy scale of inflation. The effects on high l-multipoles are suppressed by a factor {approx}1/l{sup 2} due to the falloff of D(k) for large wave vectors k. We show that the determination of generic initial conditions for the fluctuations is equivalent to the scattering problem by a potential V({eta}) localized just prior to the slow roll stage. Such potential leads to a transfer function D(k) which automatically obeys the renormalizability and small backreaction constraints. We find that an attractive potential V({eta}) yields a suppression of the lower CMB multipoles. Both for curvature and tensor modes, the quadrupole suppression depends only on the energy scale of V({eta}), and on the time interval where V({eta}) is nonzero. A suppression of the quadrupole for curvature perturbations consistent with the data is obtained when the scale of the potential is of the order of k{sub Q}{sup 2} where k{sub Q} is the wave vector whose physical wavelength is the Hubble radius today.

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

    PubMed

    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 μm 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.

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

    SciTech Connect

    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.

    2014-04-15

    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 μm 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{sup +}) beam, we tested it by accelerating both the proton (H{sup +}) and D{sup +} beams. The RFQ was operated in pulsed mode and accelerated both H{sup +} and D{sup +} 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.

  7. 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.

  8. 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.

  9. 2-MV electrostatic quadrupole injector for heavy-ion fusion

    SciTech Connect

    Bieniosek, F.M.; Celata, C.M.; Henestroza, E.; Kwan, J.W.; Prost, L.; Seidl, P.A.

    2004-11-10

    High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole (ESQ) 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 (HCX) 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.

  10. 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.

  11. Quench observation using quench antennas on RHIC IR quadrupole magnets

    SciTech Connect

    Ogitsu, T.; Terashima, A.; Tsuchiya, K.; Ganetis, G.; Muratore, J.; Wanderer, P.

    1995-07-01

    Quench observation using quench antennas is now being performed routinely on RHIC dipole and quadrupole magnets. Recently, a quench antenna was used on a RHIC IR magnet which is heavily instrumented with voltage taps. It was confirmed that the signals detected in the antenna coils do not contradict the voltage tap signals. The antenna also detects a sign of mechanical disturbance which could be related to a training quench. This paper summarizes signals detected in the antenna and discusses possible causes of these signals.

  12. Table of nuclear magnetic dipole and electric quadrupole moments

    SciTech Connect

    Stone, N.J. . E-mail: n.stone1@physics.oxford.ac.uk

    2005-05-01

    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 measurement. The literature search covers the period to late 2004. Many of the entries prior to 1988 follow those in Raghavan [At. Data Nucl. Data Tables 42 (1989) 189].

  13. Application of the Quadrupole Method for Simulation of Passive Thermography

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Zalameda, Joseph N.; Gregory, Elizabeth D.

    2017-01-01

    Passive thermography has been shown to be an effective method for in-situ and real time nondestructive evaluation (NDE) to measure damage growth in a composite structure during cyclic loading. The heat generation by subsurface flaw results in a measurable thermal profile at the surface. This paper models the heat generation as a planar subsurface source and calculates the resultant temperature profile at the surface using a three dimensional quadrupole. The results of the model are compared to finite element simulations of the same planar sources and experimental data acquired during cyclic loading of composite specimens.

  14. Small Aperture BPM to Quadrupole Assembly Tolerance Study

    SciTech Connect

    Fong, K. W.

    2010-12-07

    The LCLS injector and linac systems utilize a series of quadrupole magnets with a beam position monitor (BPM) captured in the magnet pole tips. The BPM measures the electron beam position by comparing the electrical signal from 4 electrodes and interpolating beam position from these signals. The manufacturing tolerances of the magnet and BPM are critical in determining the mechanical precision of the electrodes relative to the nominal electron beam Z-axis. This study evaluates the statistical uncertainty of the electrodes center axis relative to the nominal electron beam axis.

  15. Quadrupole Splitting Distributions in Grandidierite and Kornerupine from Antarctica

    NASA Astrophysics Data System (ADS)

    Zhe, Li; Laixi, Tong; Xiaohan, Liu; Liudong, Ren; Mingzhi, Jin; Milan, Liu

    2000-12-01

    The Mössbauer spectra of grandidierite and kornerupine at 298 and 90 K were measured. The quadrupole splitting distributions from the Mössbauer spectra were obtained by using the Voigt-based method, and the assignments for QSDs in the Mössbauer spectra of both minerals are presented. Site occupancies of iron in the crystal structures of two minerals were determined, and the chemical formulas of grandidierite and kornerupine were rewritten based on the relative absorption areas and Mössbauer fraction f for Fe3+ and Fe2+.

  16. Operational aspects of the Main Injector large aperture quadrupole (WQB)

    SciTech Connect

    Chou, W.; Bartelson, L.; Brown, B.; Capista, D.; Crisp, J.; DiMarco, J.; Fitzgerald, J.; Glass, H.; Harding, D.; Johnson, D.; Kashikhin, V.; /Fermilab

    2007-06-01

    A two-year Large Aperture Quadrupole (WQB) Project was completed in the summer of 2006 at Fermilab. [1] Nine WQBs were designed, fabricated and bench-tested by the Technical Division. Seven of them were installed in the Main Injector and the other two for spares. They perform well. The aperture increase meets the design goal and the perturbation to the lattice is minimal. The machine acceptance in the injection and extraction regions is increased from 40{pi} to 60{pi} mm-mrad. This paper gives a brief report of the operation and performance of these magnets. Details can be found in Ref [2].

  17. Beam acceleration through proton radio frequency quadrupole accelerator in BARC

    NASA Astrophysics Data System (ADS)

    Bhagwat, P. V.; Krishnagopal, S.; Mathew, J. V.; Singh, S. K.; Jain, P.; Rao, S. V. L. S.; Pande, M.; Kumar, R.; Roychowdhury, P.; Kelwani, H.; Rama Rao, B. V.; Gupta, S. K.; Agarwal, A.; Kukreti, B. M.; Singh, P.

    2016-05-01

    A 3 MeV proton Radio Frequency Quadrupole (RFQ) accelerator has been designed at the Bhabha Atomic Research Centre, Mumbai, India, for the Low Energy High Intensity Proton Accelerator (LEHIPA) programme. The 352 MHz RFQ is built in 4 segments and in the first phase two segments of the LEHIPA RFQ were commissioned, accelerating a 50 keV, 1 mA pulsed proton beam from the ion source, to an energy of 1.24 MeV. The successful operation of the RFQ gave confidence in the physics understanding and technology development that have been achieved, and indicate that the road forward can now be traversed rather more quickly.

  18. 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.

  19. Microwave spectrum, molecular structure, and quadrupole coupling of vinyl chloroformate

    NASA Astrophysics Data System (ADS)

    Bimler, Jonathan; Broadbent, Stacy; Utzat, Karissa A.; Bohn, Robert K.; Restrepo, Albeiro; Harvey Michels, H.; True, Nancy S.

    2012-09-01

    Vinyl chloroformate is confirmed to have the planar structure reported in an earlier study [1]. Our study uses much higher resolution microwave rotational spectra and ab initio calculations have been extended to a higher level. Naturally abundant isotopologs with single substitution of 37Cl, 13C, and 18O isotopes have also been measured and a substitution structure obtained. The quadrupole coupling constants of the 35Cl and 37Cl isotopologs have been determined. The potential energy profiles of internal rotation about the Odbnd Csbnd Osbnd C and Csbnd Osbnd Cdbnd C dihedral angles have been calculated.

  20. Novel integrated design framework for radio frequency quadrupoles

    NASA Astrophysics Data System (ADS)

    Jolly, Simon; Easton, Matthew; Lawrie, Scott; Letchford, Alan; Pozimski, Jürgen; Savage, Peter

    2014-01-01

    A novel design framework for Radio Frequency Quadrupoles (RFQs), developed as part of the design of the FETS RFQ, is presented. This framework integrates several previously disparate steps in the design of RFQs, including the beam dynamics design, mechanical design, electromagnetic, thermal and mechanical modelling and beam dynamics simulations. Each stage of the design process is described in detail, including the various software options and reasons for the final software suite selected. Results are given for each of these steps, describing how each stage affects the overall design process, with an emphasis on the resulting design choices for the FETS RFQ.

  1. Design of an rf quadrupole for Landau damping

    NASA Astrophysics Data System (ADS)

    Papke, K.; Grudiev, A.

    2017-08-01

    The recently proposed superconducting quadrupole resonator for Landau damping in accelerators is subjected to a detailed design study. The optimization process of two different cavity types is presented following the requirements of the High Luminosity Large Hadron Collider (HL-LHC) with the main focus on quadrupolar strength, surface peak fields, and impedance. The lower order and higher order mode (LOM and HOM) spectrum of the optimized cavities is investigated and different approaches for their damping are proposed. On the basis of an example the first two higher order multipole errors are calculated. Likewise on this example the required rf power and optimal external quality factor for the input coupler is derived.

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

    DOEpatents

    Felter, Thomas E.

    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.

  3. Optimized Superconducting Quadrupole Arrays for Multiple Beam Transport

    SciTech Connect

    Meinke, Rainer, B.; Goodzeit, Carl, L.; Ball, Millicent, J.

    2005-09-20

    This research project advanced the development of reliable, cost-effective arrays of superconducting quadrupole magnets for use in multi-beam inertial fusion accelerators. The field in each array cell must be identical and meet stringent requirements for field quality and strength. An optimized compact array design using flat double-layer pancake coils was developed. Analytical studies of edge termination methods showed that it is feasible to meet the requirements for field uniformity in all cells and elimination of stray external field in several ways: active methods that involve placement of field compensating coils on the periphery of the array or a passive method that involves use of iron shielding.

  4. Global investigation of the fine structure of the isoscalar giant quadrupole resonance

    SciTech Connect

    Shevchenko, A.; Burda, O.; Kalmykov, Y.; Neumann-Cosel, P. von; Ponomarev, V. Yu.; Richter, A.; Wambach, J.; Carter, J.; Sideras-Haddad, E.; Cooper, G. R. J.; Fearick, R. W.; Foertsch, S. V.; Lawrie, J. J.; Neveling, R.; Smit, F. D.; Fujita, H.; Fujita, Y.; Lacroix, D.

    2009-04-15

    Fine structure in the region of the isoscalar giant quadrupole resonance (ISGQR) in {sup 58}Ni, {sup 89}Y, {sup 90}Zr, {sup 120}Sn, {sup 166}Er, and {sup 208}Pb has been observed in high-energy-resolution ({delta}E{sub 1/2}{approx_equal}35-50 keV) inelastic proton scattering measurements at E{sub 0}=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 mixing of one-particle one-hole states with two-particle two-hole states is taken into account. A detailed comparison of the experimental data is made with results from the quasiparticle-phonon model (QPM) and the extended time-dependent Hartree-Fock (ETDHF) method. For {sup 208}Pb, additional theoretical results from second RPA and the extended theory of finite Fermi systems (ETFFS) are discussed. A continuous wavelet analysis of the experimental and the calculated spectra is used to extract dominant scales characterizing the fine structure. Although the calculations agree with qualitative features of these scales, considerable differences are found between the model and experimental results and amongst different models. Within the framework of the QPM and ETDHF calculations it is possible to decompose the model spaces into subspaces approximately corresponding to different damping mechanisms. It is demonstrated that characteristic scales mainly arise from the collective coupling of the ISGQR to low-energy surface vibrations.

  5. Rapid Analysis of Components in Coptis chinensis Franch by Ultra-Performance Liquid Chromatography with Quadrupole Time-of-Flight Mass Spectrometry

    PubMed Central

    Tian, Peng-peng; Zhang, Xiao-xu; Wang, Hong-ping; Li, Pu-ling; Liu, Yu-xin; Li, Shao-jing

    2017-01-01

    Background: Coptis chinensis Franch is a traditional Chinese medical herb. Objective: In this article, ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to rapidly, qualitatively, and comprehensively identify the components in Coptis chinensis Franch. Materials and Methods: Chromatographic separation was achieved on an Agilent Zorbax RRHD Eclipse Plus C18 column. The mobile phase consisted of 0.1% formic acid water (A) and 0.1% formic acid acetonitrile (B) with a gradient program. Qualitative analysis was performed on an Agilent 6540 quadrupole time-of-flight mass spectrometer, which was equipped with a Dual AJS ESI source operating in negative mode. Results: A total of 30 alkaloid and non-alkaloid components of Coptis chinensis Franch were identified in only 14 min. Conclusion: This study helped to provide a basis for the quality control of Coptis chinensis Franch. SUMMARY Qualitative analysis method of chlorogenic alkaloids and non-alkaloids in Coptis chinensis Franch is developed by Ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) method.Established UPLC-Q-TOF-MS/MS analysis method is validated with rapidness and accuracy.The developed method was successfully applied for qualitative analysis of Coptis chinensis Franch sample collected from cultivation place in China. Abbreviations used: Q-TOF-MS: quadrupole time-of-flight mass spectrometry, UPLC: ultra-performance liquid chromatography, pos: positive, neg: negative. Q-TOF-MS: quadrupole time-of-flight mass spectrometry, UPLC: ultra-performance liquid chromatography, pos: positive, neg: negative. UPLC: ultra-performance liquid chromatography, pos: positive, neg: negative. pos: positive, neg: negative. neg: negative. PMID:28216903

  6. Low-frequency nuclear quadrupole resonance with a dc SQUID

    SciTech Connect

    Chang, J.W.

    1991-07-01

    Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and application of a SQUID NQR technique which is capable of measuring intermediate strength quadrupolar interactions, in the range of a few hundred kilohertz to several megahertz. In this technique, a dc SQUID (Superconducting QUantum Interference Device) is used to monitor the longitudinal sample magnetization, as opposed to the transverse magnetization, as a rf field is swept in frequency. This allows the detection of low-frequency nuclear quadrupole resonances over a very wide frequency range with high sensitivity. The theory of this NQR technique is discussed and a description of the dc SQUID system is given. In the following chapters, the spectrometer is discussed along with its application to the study of samples containing half-odd-integer spin quadrupolar nuclei, in particular boron-11 and aluminum-27. The feasibility of applying this NQR technique in the study of samples containing integer spin nuclei is discussed in the last chapter. 140 refs., 46 figs., 6 tabs.

  7. High Reliability Prototype Quadrupole for the Next Linear Collider

    NASA Astrophysics Data System (ADS)

    Spencer, C. M.

    2001-01-01

    The Next Linear Collider (NLC) will require over 5600 magnets, each of which must be highly reliable and/or quickly repairable in order that the NLC reach its 85/ overall availability goal. A multidiscipline engineering team was assembled at SLAC to develop a more reliable electromagnet design than historically had been achieved at SLAC. This team carried out a Failure Mode and Effects Analysis (FMEA) on a standard SLAC quadrupole magnet system. They overcame a number of longstanding design prejudices, producing 10 major design changes. This paper describes how a prototype magnet was constructed and the extensive testing carried out on it to prove full functionality with an improvement in reliability. The magnet's fabrication cost will be compared to the cost of a magnet with the same requirements made in the historic SLAC way. The NLC will use over 1600 of these 12.7 mm bore quadrupoles with a range of integrated strengths from 0.6 to 132 Tesla, a maximum gradient of 135 Tesla per meter, an adjustment range of 0 to -20/ and core lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20/ adjustment. A magnetic measurement set-up has been developed that can measure sub-micron shifts of a magnetic center. The prototype satisfied the center shift requirement over the full range of integrated strengths.

  8. High Reliability Prototype Quadrupole for the Next Linear Collider

    SciTech Connect

    Spencer, Cherrill M

    2001-01-04

    The Next Linear Collider (NLC) will require over 5600 magnets, each of which must be highly reliable and/or quickly repairable in order that the NLC reach its 85% overall availability goal. A multidiscipline engineering team was assembled at SLAC to develop a more reliable electromagnet design than historically had been achieved at SLAC. This team carried out a Failure Mode and Effects Analysis (FMEA) on a standard SLAC quadrupole magnet system. They overcame a number of longstanding design prejudices, producing 10 major design changes. This paper describes how a prototype magnet was constructed and the extensive testing carried out on it to prove full functionality with an improvement in reliability. The magnet's fabrication cost will be compared to the cost of a magnet with the same requirements made in the historic SLAC way. The NLC will use over 1600 of these 12.7 mm bore quadrupoles with a range of integrated strengths from 0.6 to 132 Tesla, a maximum gradient of 135 Tesla per meter, an adjustment range of 0 to -20% and core lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. A magnetic measurement set-up has been developed that can measure sub-micron shifts of a magnetic center. The prototype satisfied the center shift requirement over the full range of integrated strengths.

  9. Low-frequency nuclear quadrupole resonance with a dc SQUID

    SciTech Connect

    Chang, J.W.

    1991-07-01

    Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and application of a SQUID NQR technique which is capable of measuring intermediate strength quadrupolar interactions, in the range of a few hundred kilohertz to several megahertz. In this technique, a dc SQUID (Superconducting QUantum Interference Device) is used to monitor the longitudinal sample magnetization, as opposed to the transverse magnetization, as a rf field is swept in frequency. This allows the detection of low-frequency nuclear quadrupole resonances over a very wide frequency range with high sensitivity. The theory of this NQR technique is discussed and a description of the dc SQUID system is given. In the following chapters, the spectrometer is discussed along with its application to the study of samples containing half-odd-integer spin quadrupolar nuclei, in particular boron-11 and aluminum-27. The feasibility of applying this NQR technique in the study of samples containing integer spin nuclei is discussed in the last chapter. 140 refs., 46 figs., 6 tabs.

  10. Nuclear electric quadrupole moment of potassium from the molecular method

    NASA Astrophysics Data System (ADS)

    Teodoro, Tiago Quevedo; Haiduke, Roberto Luiz Andrade; Visscher, Lucas

    2015-03-01

    The current standard nuclear quadrupole moments (NQMs) of the 39K , 40K , and 41K isotopes have recently been contested by Singh and co-workers on the basis of their atomic computational data [Singh et al., Phys. Rev. A 86, 032509 (2012), 10.1103/PhysRevA.86.032509]. Thus we performed relativistic calculations of electric field gradients at the potassium nuclei in three diatomic molecules (KF, KCl, and KBr) and combined these values with accurate experimental nuclear quadrupole coupling constants to provide an independent assessment of these NQMs. Our most accurate results, obtained by treating electron correlation with coupled cluster theory, employing a four-component Hamiltonian that includes the Gaunt two-electron correction, and with an incremented relativistic basis set of quadruple-ζ quality, yield Q (39K)=60.3 (6 ) , Q (40K)=-75.0 (8 ) , and Q (41K)=73.4 (7 ) mb . These values are in better agreement with the results obtained by Singh et al. and indicate that the standard NQMs should be revised.

  11. VIBRATION MEASUREMENTS IN A RHIC QUADRUPOLE AT CRYOGENIC TEMPERATURES.

    SciTech Connect

    JAIN, A.; AYDIN, S.; HE, P.; ANERELLA, M.; GANETIS, G.; HARRISON, M.; PARKER, B.; PLATE, S.

    2005-10-17

    One of the concerns in using compact superconducting magnets in the final focus region of the ILC is the influence of the cryogen flow on the vibration characteristics. As a first step towards characterizing such motion at nanometer levels, a project was undertaken at BNL to measure the vibrations in a spare RHIC quadrupole under cryogenic conditions. Given the constraints of cryogenic operation, and limited space available, it was decided to use a dual head laser Doppler vibrometer for this work. The performance of the laser vibrometer was tested in a series of room temperature tests and compared with results from Mark L4 geophones. The laser system was then used to measure the vibration of the cold mass of the quadrupole with respect to the outside warm enclosure. These measurements were carried out both with and without the flow of cold helium through the magnet. The results indicate only a minor increase in motion in the horizontal direction (where the cold mass is relatively free to move).

  12. The quadrupole moments of Cd and Zn isotopes - an apology

    NASA Astrophysics Data System (ADS)

    Haas, H.; Barbosa, M. B.; Correia, J. G.

    2016-12-01

    In 2010 we presented an update of the nuclear quadrupole moments (Q) for the Cd and Zn isotopes, based essentially on straightforward density functional (DF) calculations (H. Haas and J.G. Correia, Hyperfine Interact 198, 133-137 (2010)). It has been apparent for some years that the standard DF procedure obviously fails, however, to reproduce the known electric-field gradient (EFG) for various systems, typical cases being Cu2O, As and Sb, and the solid halogens. Recently a cure for this deficiency has been found in the hybrid DF technique. This method is now applied to solid Cd and Zn, and the resultant quadrupole moments are about 15 % smaller than in our earlier report. Also nuclear systematics, using the recently revised values of Q for the long-lived 11/2 isomers in111Cd to129Cd, together with earlier PAD data for107,109Cd, leads to the same conclusion. In addition, EFG calculations for the cadmium dimethyl molecule further support the new values: Q(111Cd, 5/2+) = .683(20) b, Q(67Zn, gs) = .132(5) b. This implies, that the value for the atomic EFG in the 3it {P}1 state of Zn must be revised, as it has been for Cd.

  13. Precision Magnet Measurements for X-Band Accelerator Quadrupole Triplets

    SciTech Connect

    Marsh, R A; Anderson, S G; Armstrong, J P

    2012-05-16

    An X-band test station is being developed at LLNL to investigate accelerator optimization for future upgrades to mono-energetic gamma-ray (MEGa-Ray) technology at LLNL. Beamline magnets will include an emittance compensation solenoid, windowpane steering dipoles, and quadrupole magnets. Demanding tolerances have been placed on the alignment of these magnets, which directly affects the electron bunch beam quality. A magnet mapping system has been established at LLNL in order to ensure the delivered magnets match their field specification, and the mountings are aligned and capable of reaching the specified alignment tolerances. The magnet measurement system will be described which uses a 3-axis Lakeshore gauss probe mounted on a 3-axis translation stage. Alignment accuracy and precision will be discussed, as well as centering measurements and analysis. The dependence on data analysis over direct multi-pole measurement allows a significant improvement in useful alignment information. Detailed analysis of measurements on the beamline quadrupoles will be discussed, including multi-pole content both from alignment of the magnets, and the intrinsic level of multi-pole magnetic field.

  14. 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.

  15. Heavy ion plasma confinement in an RF quadrupole trap

    NASA Technical Reports Server (NTRS)

    Schermann, J.; Major, F. G.

    1971-01-01

    The confinement of an electron free plasma in a pure quadrupole RF electric trap was considered. The ultimate goal was to produce a large density of mercury ions, in order to realize a trapped ion frequency standard using the hyperfine resonance of 199 Hg(+) at 40.7 GHz. An attempt was made to obtain an iodine plasma consisting of equal numbers of positive and negative ions of atomic iodine, the positive iodine ions, being susceptible to charge-exchange with mercury atoms, will produce the desired mercury ions. The experiment showed that the photoproduction of ions pairs in iodine using the necessary UV radiation occurs with a small cross-section, making it difficult to demonstrate the feasibility of space charge neutralization in a quadrupole trap. For this reason it was considered expedient to choose thallium iodide, which has a more favorable absorption spectrum (in the region of 2000 to 2100 A). The results indicate that, although the ionic recombination is a serious limiting factor, a considerable improvement can be obtained in practice for the density of trapped ions, with a considerable advantage in lifetimes for spectroscopic purposes. The ion pair formation by photoionization is briefly reviewed.

  16. Development and testing of the improved focusing quadrupole for heavy ion fusion accelerators

    SciTech Connect

    Manahan, R R; Martovetsky, N N; Meinke, R B; Chiesa, L; Lietzke, A F; Sabbi, G L; Seidl, P A

    2003-10-23

    An improved version of the focusing magnet for a Heavy Ion Fusion (HIF) accelerator was designed, built and tested in 2002-2003. This quadrupole has higher focusing power and lower error field than the previous version of the focusing quadrupoles successfully built and tested in 2001. We discuss the features of the new design, selected fabrication issues and test results.

  17. The quadrupole coupling constant of HNC. [hydrogen isocyanide hyperfine structure measurements

    NASA Technical Reports Server (NTRS)

    Snyder, L. E.; Hollis, J. M.; Buhl, D.

    1977-01-01

    The letter reports resolved measurements of the quadrupole hyperfine structure of HNC (hydrogen isocyanide). These measurements were made in the direction of the cool interstellar dust cloud L134, and were used to make an experimental determination of a fundamental spectroscopic constant of HNC, its quadrupole coupling constant.

  18. 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; Brueck, Heinrich; 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.

  19. Determination of nuclear quadrupole moments – An example of the synergy of ab initio calculations and microwave spectroscopy

    SciTech Connect

    Kellö, Vladimir

    2015-01-22

    Highly correlated scalar relativistic calculations of electric field gradients at nuclei in diatomic molecules in combination with accurate nuclear quadrupole coupling constants obtained from microwave spectroscopy are used for determination of nuclear quadrupole moments.

  20. A superconducting quadrupole magnet array for a heavy ion fusion driver

    SciTech Connect

    Caspi, S.; Bangerter, r.; Chow, K.; Faltens, A.; Gourley, S.; Hinkins, R.; Gupta, R.; Lee, E.; McInturff, A.; Scanlan, R.; Taylor, C.; Wolgast, D.

    2000-06-27

    A multi-channel quadrupole array has been proposed to increase beam intensity and reduce space charge effects in a Heavy Ion Fusion Driver. A single array unit composed of several quadrupole magnets, each with its own beam line, will be placed within a ferromagnetic accelerating core whose cost is directly affected by the array size. A large number of focusing arrays will be needed along the accelerating path. The use of a superconducting quadrupole magnet array will increase the field and reduce overall cost. We report here on the design of a compact 3 x 3 superconducting quadrupole magnet array. The overall array diameter and length including the cryostat is 900 x 700 mm. Each of the 9 quadrupole magnets has a 78 mm warm bore and an operating gradient of 50 T/m over an effective magnetic length of 320 mm.

  1. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Fuerstenau, Stephen D. (Inventor); Orient, Otto J. (Inventor); Yee, Karl Y. (Inventor); Rice, John T. (Inventor)

    2002-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter, or pole array, for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  2. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Fuerstenau, Stephen D. (Inventor); Orient, Otto J. (Inventor); Yee, Karl Y. (Inventor); Rice, John T. (Inventor)

    2000-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter, or pole array, for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  3. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Fuerstenau, Stephen D. (Inventor); Orient, Otto J. (Inventor); Yee, Karl Y. (Inventor); Rice, John T. (Inventor)

    2001-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter, or pole array, for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  4. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael (Inventor); Orient, Otto (Inventor); Wiberg, Dean (Inventor); Brennen, Reid A. (Inventor)

    2001-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and aligrnent for use in a final quadrupole mass spectrometer device.

  5. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael (Inventor); Orient, Otto (Inventor); Wiberg, Dean (Inventor); Brennen, Reid A. (Inventor)

    2001-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  6. Miniature micromachined quadrupole mass spectrometer array and method of making the same

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara (Inventor); Hecht, Michael (Inventor); Orient, Otto (Inventor); Wiberg, Dean (Inventor); Brennen, Reid A. (Inventor)

    2000-01-01

    The present invention provides a quadrupole mass spectrometer and an ion filter for use in the quadrupole mass spectrometer. The ion filter includes a thin patterned layer including a two-dimensional array of poles forming one or more quadrupoles. The patterned layer design permits the use of very short poles and with a very dense spacing of the poles, so that the ion filter may be made very small. Also provided is a method for making the ion filter and the quadrupole mass spectrometer. The method involves forming the patterned layer of the ion filter in such a way that as the poles of the patterned layer are formed, they have the relative positioning and alignment for use in a final quadrupole mass spectrometer device.

  7. The influence of quadrupole sources in the boundary layer and wake of a blade on helicopter rotor noise

    NASA Technical Reports Server (NTRS)

    Farassat, F.; Brentner, Kenneth S.

    1991-01-01

    It is presently noted that, for an observer in or near the plane containing a helicopter rotor disk, and in the far field, part of the volume quadrupole sources, and the blade and wake surface quadrupole sources, completely cancel out. This suggests a novel quadrupole source description for the Ffowcs Williams-Hawkings equation which retain quadrupoles with axes parallel to the rotor disk; in this case, the volume and shock surface sourse terms are dominant.

  8. 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.

  9. 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.

  10. Plasma-beam traps and radiofrequency quadrupole beam coolers.

    PubMed

    Maggiore, M; Cavenago, M; Comunian, M; Chirulotto, F; Galatà, A; De Lazzari, M; Porcellato, A M; Roncolato, C; Stark, S; Caruso, A; Longhitano, A; Cavaliere, F; Maero, G; Paroli, B; Pozzoli, R; Romé, M

    2014-02-01

    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.

  11. Plasma-beam traps and radiofrequency quadrupole beam coolers

    SciTech Connect

    Maggiore, M. Cavenago, M.; Comunian, M.; Chirulotto, F.; Galatà, A.; De Lazzari, M.; Porcellato, A. M.; Roncolato, C.; Stark, S.; Caruso, A.; Longhitano, A.; Cavaliere, F.; Maero, G.; Paroli, B.; Pozzoli, R.; Romé, M.

    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.

  12. Physics design of rod type proton Radio Frequency Quadrupole linac

    NASA Astrophysics Data System (ADS)

    Das, C.; Dechoudhury, S.; Pandey, H. K.; Naik, V.; Chakrabarti, A.

    2017-02-01

    A Radio Frequency Quadrupole (RFQ) linac delivering 800 keV, 5 mA protons has been designed. It is envisaged as first injector of the proton driver that will be used for production of proton-rich radioactive beams in the proposed ANURIB facility. The option of rod-type structure at frequency of 80 MHz has been chosen owing to ease of mechanical fabrications and to avoid detrimental nearby dipole modes present in vane type structure. Optimization of parameters has been carried out for a viable length and power of RFQ in order to avoid any infrastructural complexity. Conventional method of keeping focusing factor and vane voltage constant along the length of RFQ has been adopted. Results of detailed beam dynamics and RF structure design, space charge induced effects and corroborative particle tracking with realistic 3D fields of modulated vane has been presented.

  13. Multiparticle losses in a linear quadrupole Paul trap

    NASA Astrophysics Data System (ADS)

    Semerikov, I. A.; Zalivako, I. V.; Shpakovskii, T. V.; Borisenko, A. S.; Khabarova, K. Yu.; Sorokin, V. N.; Kolachevsky, N. N.

    2016-10-01

    A linear quadrupole Paul trap is fabricated for capturing magnesium and aluminium ions. An experimental cycle performed has demonstrated ion capture and holding in a trap with an average ion lifetime of 1.7 {\\text{s}}. Modelling of ion dynamics in the trap shows that the main mechanism responsible for losses of hot ions is multiparticle interaction, which results in that a kinetic energy of some ions increases and they leave the trapping zone. This mechanism is completely suppressed if ions are cooled. Another mechanism is the charge exchange; however, it is not substantial at a high average energy of ions produced in the result of an electron impact. Parameters of the trap allow one to perform precision spectroscopic measurements and to control ion quantum states.

  14. On quadrupole and octupole gravitational radiation in the ANK formalism

    NASA Astrophysics Data System (ADS)

    Kozameh, Carlos N.; Ortega, R. G.; Rojas, T. A.

    2017-04-01

    Following the approach of Adamo-Newman-Kozameh (ANK) we derive the equations of motion for the center of mass and intrinsic angular moment for isolated sources of gravitational waves in axially symmetric spacetimes. The original ANK formulation is generalized so that the angular momentum coincides with the Komar integral for a rotational Killing symmetry. This is done using the Winicour-Tamburino Linkages which yields the mass dipole-angular momentum tensor for the isolated sources. The ANK formalism then provides a complex worldline in a fiducial flat space to define the notions of center of mass and spin. The equations of motion are derived and then used to analyse a very simple astrophysical process where only quadrupole and octupole contributions are included. The results are then compared with those coming from the post newtonian approximation.

  15. Uranus' (3-0) H2 quadrupole line profiles

    NASA Astrophysics Data System (ADS)

    Trafton, L.

    1987-04-01

    Spectra of Uranus' S3(0) and S3(1) H2 quadrupole lines, obtained during the 1978-1980 apparitions, are analyzed, and are found to require the presence of a deep cloud. Modifications of the Baines and Bergstralh (1986) standard model, including an additional haze layer above the 16-km-am H2 level which contains strongly absorbing particles, are needed to fit the observations. For a Rayleigh phase function, such a haze (uniformly mixed with the gas above this level) would have an absorption optical depth of 0.16 and a single scattering particle albedo of 0.30. This modification would imply a fraction of normal H2 equal to 0.25 + or - 0.10, in agreement with the Baines and Bergstralh standard model.

  16. Covariant spectator theory of np scattering: Deuteron quadrupole moment

    SciTech Connect

    Gross, Franz

    2015-01-26

    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 XEFT predictions to order N3LO.

  17. Design and fabrication of the BNL radio frequency quadrupole

    SciTech Connect

    McKenzie-Wilson, R.B.

    1983-01-01

    The Brookhaven National Laboratory polarized H/sup -/ injection program for the AGS will utilize a Radio Frequency Quadrupole for acceleration between the polarized source and the Alvarez Linac. Although operation will commence with a few ..mu.. amperes of H/sup -/ current, it is anticipated that future polarized H/sup -/ sources will have a considerably improved output. The RFQ will operate at 201.25 MHz and will be capable of handling a beam current of 0.02 amperes with a duty cycle of 0.25%. The resulting low average power has allowed novel solutions to the problems of vane alignment, rf current contacts, and removal of heat from the vanes. The cavity design philosophy will be discussed together with the thermodynamics of heat removal from the vane. Details of the fabrication will be presented with a status report.

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

    SciTech Connect

    Park, Jae; Krstić, Predrag S.

    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.

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

    DOE PAGES

    Park, Jae; Krstić, Predrag S.

    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 fluctuationsmore » 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.« less

  20. Covariant spectator theory of np scattering: Deuteron quadrupole moment

    DOE PAGES

    Gross, Franz

    2015-01-26

    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 » XEFT predictions to order N3LO.« less

  1. 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.

  2. Mixed radiation field dosimetry utilizing Nuclear Quadrupole Resonance

    SciTech Connect

    Hintenlang, D.

    1991-01-01

    This project has proposed to develop a novel dosimetry system that is capable of directly evaluating the chemical/biological damage caused by neutrons, photons, or both in a single measurement. The dosimeter itself will consist of a small volume of biological equivalent material that is probed for radiation damage with Nuclear Quadrupole Resonance (NQR) techniques. NQR has previously been utilized as a sensitive probe of structural and chemical changes at the molecular level for a variety of organic compounds. The biological equivalent materials used in this study will not only have a density similar to tissue (tissue equivalent) but will have the same atomic components as tissue. This is a significant requirement if the important neutron interactions that occur in tissue are to occur in the dosimeter as well. The overall objective of this study is to investigate a methodology to perform accurate mixed-field (neutron and photon) dosimetry for biological systems.

  3. Nuclear quadrupole resonance studies of amorphous, orthorhombic, and rhombohedral arsenic

    SciTech Connect

    Jellison, G.E. Jr.; Petersen, G.L.; Taylor, P.C.

    1980-10-15

    Pulsed nuclear quadrupole resonance (NQR) experiments have been performed on three forms of elemental arsenic: amorphous (a), rhombohedral (rh), and orthorhombic (or). The temperature dependence of the spin-lattice relaxation time (T/sub 1/) provides evidence for the existence of disorder (tunneling) modes in a-As. It is found that the NQR line shape of a-As is highly asymmetric, and this asymmetry is attributed to a distribution of dihedral angles in a-As. The observed NQR frequencies indicate that the amount of bonding s admixture is different in each material (rh-As:3%, or-As:7%, a-As:10%). Simple calculations in comparison with x-ray results indicate that the bonding configurations in these three forms of arsenic do not necessarily correspond to maximum overlap of bonding orbitals on adjacent atoms.

  4. Quasiclassical description of bremsstrahlung accompanying {alpha} decay including quadrupole radiation

    SciTech Connect

    Jentschura, U. D.; Milstein, A. I.; Terekhov, I. S.; Boie, H.; Scheit, H.; Schwalm, D.

    2008-01-15

    We present a quasiclassical theory of {alpha} decay accompanied by bremsstrahlung with a special emphasis on the case of {sup 210}Po, with the aim of finding a unified description that incorporates both the radiation during the tunneling through the Coulomb wall and the finite energy E{sub {gamma}} of the radiated photon up to E{sub {gamma}}{approx}Q{sub {alpha}}/{radical}({eta}), where Q{sub {alpha}} is the {alpha}-decay Q-value and {eta} is the Sommerfeld parameter. The corrections with respect to previous quasiclassical investigations are found to be substantial, and excellent agreement with a full quantum mechanical treatment is achieved. Furthermore, we find that a dipole-quadrupole interference significantly changes the {alpha}-{gamma} angular correlation. We obtain good agreement between our theoretical predictions and experimental results.

  5. A Cryogenic test stand for LHC quadrupole magnets

    SciTech Connect

    R. J. Rabehl et al.

    2004-03-09

    A new test stand for testing LHC interaction region (IR) quadrupole magnets at the Fermilab Magnet Test Facility has been designed and operated. The test stand uses a double bath system with a lambda plate to provide the magnet with a stagnant bath of pressurized He II at 1.9 K and 0.13 MPa. A cryostated magnet 0.91 m in diameter and up to 13 m in length can be accommodated. This paper describes the system design and operation. Issues related to both 4.5 K and 1.9 K operations and magnet quenching are highlighted. An overview of the data acquisition and cryogenics controls systems is also included.

  6. Super Strong Permanent Magnet Quadrupole for a Linear Collider

    SciTech Connect

    Mihara, Takanori

    2004-02-19

    The field strength generated by permanent magnets has been further extended by the introduction of saturated iron. A permanent magnet quadrupole (PMQ) lens with such saturated iron is one of the candidates for the final focus lens for an e{sup +}e{sup -} Linear Collider accelerator, because of its compactness and low power consumption. The first prototype of the PMQ has been fabricated and demonstrated to have an integrated strength of 28.5T with an overall length of 10 cm and a 7mm bore radius. Two drawbacks should be considered: its negative temperature coefficient of field strength and its fixed strength. A thermal compensation material is being tested to cure the first problem. The other problem may be solved by rotating sectioned magnet bricks, but that may lead to movement of the magnetic center and introduction of multipoles beyond some strict requirements.

  7. 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].

  8. Nuclear quadrupole resonance study of hydrogen bonded solid materials.

    PubMed

    Seliger, Janez

    2011-09-01

    Nuclear quadrupole resonance is presented as a method for the study of solid hydrogen bonded materials. NQR study of hydrogen bonds in ferroelectric and paraelectric KH2PO4, antiferroelectric and paraelectric squaric acid, ferroelectric croconic acid and antiferroelectric and paraelectric cocrystal 5'-dimethyl-2, 2'-bipyridine - chloranilic acid (1:1) are discussed in more details. A 14N NQR study of the strong short O-HKN hydrogen bond in two polymorphic forms of cocrystal isonicotinamide-oxalic acid (2:1) is presented as well. Various correlations between the NQR parameters and between the NQR and structural parameters have been observed. These correlations may be used to determine the proton position in a hydrogen bond and some other structural parameters from the NQR data.

  9. 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.

  10. Fluorescence Imaging for Visualization of the Ion Cloud in a Quadrupole Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Talbot, Francis O.; Sciuto, Stephen V.; Jockusch, Rebecca A.

    2013-12-01

    Laser-induced fluorescence is used to visualize populations of gaseous ions stored in a quadrupole ion trap (QIT) mass spectrometer. Presented images include the first fluorescence image of molecular ions collected under conditions typically used in mass spectrometry experiments. Under these "normal" mass spectrometry conditions, the radial ( r) and axial ( z) full-width at half maxima (FWHM) of the detected ion cloud are 615 and 214 μm, respectively, corresponding to ~6 % of r 0 and ~3 % of z 0 for the QIT used. The effects on the shape and size of the ion cloud caused by varying the pressure of helium bath gas, the number of trapped ions, and the Mathieu parameter q z are visualized and discussed. When a "tickle voltage" is applied to the exit end-cap electrode, as is done in collisionally activated dissociation, a significant elongation in the axial, but not the radial, dimension of the ion cloud is apparent. Finally, using spectroscopically distinguishable fluorophores of two different m/ z values, images are presented that illustrate stratification of the ion cloud; ions of lower m/ z (higher q z ) are located in the center of the trapping region, effectively excluding higher m/ z (lower q z ) ions, which form a surrounding layer. Fluorescence images such as those presented here provide a useful reference for better understanding the collective behavior of ions in radio frequency (rf) trapping devices and how phenomena such as collisions and space-charge affect ion distribution.

  11. Electric quadrupole transitions for some isotopes of Xenon; considering rigidity for γ = 30∘ collective parameter

    NASA Astrophysics Data System (ADS)

    Sobhani, Hadi; Hassanabadi, Hassan

    2017-01-01

    In this article, Davydov-Chaban Hamiltonian is investigated in presence of Davidson potential. Using analytical approach, wave function corresponding of considered system has been derived. Then energy spectra and B(E2) transition rate have been calculated numerically in detail as well. The results are compared with experimental data for three isotope of Xenon.

  12. Collective Inertia and Fission Barriers Within the Skyrme-Hartree-Fock Theory

    SciTech Connect

    Baran, A.; Staszczak, A.; Dobaczewski, J.; Nazarewicz, Witold

    2007-01-01

    Spontaneous fission barriers, quadrupole inertia tensor, and zero-point quadrupole correlation energy are calculated for 252,256,258Fm in the framework of the self-consistent Skyrme-Hartree-Fock+BCS theory. Two ways of computing collective inertia are employed: the Gaussian Overlap Approximation to the Generator Coordinate Method and cranking ansatz. The Skyrme results are compared with those of the Gogny-Hartree-Fock-Bogoliubov model.

  13. 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.

  14. 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.; 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.

  15. Electron Cloud Generation And Trapping in a Quadrupole Magnet at the Los Alamos PSR

    SciTech Connect

    Macek, R.J.; Browman, A.A.; Ledford, J.E.; Borden, M.J.; O'Hara, J.F.; McCrady, R.C.; Rybarcyk, L.J.; Spickermann, T.; Zaugg, T.J.; Pivi, M.T.F.; /SLAC

    2007-11-14

    A diagnostic to measure electron cloud formation and trapping in a quadrupole magnet has been developed, installed, and successfully tested at PSR. Beam studies with this diagnostic show that the electron flux striking the wall in the quadrupole is comparable to or larger than in an adjacent drift. In addition, the trapped electron signal, obtained using the sweeping feature of diagnostic, was larger than expected and decayed very slowly with an exponential time constant of 50 to 100 {micro}s. Experimental results were also obtained which suggest that a significant fraction of the electrons observed in the adjacent drift space were seeded by electrons ejected from the quadrupole.

  16. First Test Results of the 150 mm Aperture IR Quadrupole Models for the High Luminosity LHC

    SciTech Connect

    Ambrosio, G.; Chlachidze, G.; Wanderer, P.; Ferracin, P.; Sabbi, G.

    2016-10-06

    The High Luminosity upgrade of the LHC at CERN will use large aperture (150 mm) quadrupole magnets to focus the beams at the interaction points. The high field in the coils requires Nb3Sn superconductor technology, which has been brought to maturity by the LHC Accelerator Re-search Program (LARP) over the last 10 years. The key design targets for the new IR quadrupoles were established in 2012, and fabrication of model magnets started in 2014. This paper discusses the results from the first single short coil test and from the first short quadrupole model test. Remaining challenges and plans to address them are also presented and discussed.

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

    SciTech Connect

    Gökçe, Yasin; Çelik, Gültekin; Yıldız, Murat

    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. Design and testing of the magnetic quadrupole for the Heavy Ion Fusion Program

    SciTech Connect

    Benjegerdes, R.; Faltens, A.; Fawley, W.; Peters, C.; Reginato, L.; Stuart, M.

    1995-04-01

    The Heavy Ion Fusion Program at the Lawrence Berkeley Laboratory is conducting experiments in the transport and acceleration of ``driverlike`` beams. The single beam coming from the four-to-one beam combiner will be transported in a lattice of pulsed magnetic quadrupoles. The present beam transport consists of high field, short aspect ratio magnetic quadrupoles to maximize the transportable current. This design could also be converted to be superconducting for future uses in a driver. The pulsed quadrupole will develop a maximum field of two Tesla and will be housed within the induction accelerator cells at the appropriate lattice period. Hardware implementation of the physics requirements and full parameter testing is described.

  19. Fast Fourier Transform Chlorine Nuclear Quadrupole Resonance Spectroscopy.

    NASA Astrophysics Data System (ADS)

    D'Iorio, Marie

    A nuclear quadrupole resonance spectrometer operating in the frequency range 1-40 MHz was updated for fast Fourier transform spectroscopy and coupled to a Nicolet 1180 computer and data acquisition system. It was used with a low temperature cryostat for studies shown down to liquid helium temperature and with a high pressure/low temperature system for studies down to liquid nitrogen temperature and up to six kilobars. The study of the ('35)Cl NQR spectrum of K(,2)OsCl(,6) at 298 K and 77 K revealed the presence of a satellite associated with the nearest neighbour chlorines to H('+) ion impurities located at vacant octahedral sties. This result is in agreement with the predictions of a point charge model calculation. A residence time for the H('+) ion was deduced and is consistent with the result obtained from dielectric measurements. A detailed study of the ('35)Cl NQR frequency in K(,2)ReCl(,6) was performed in the temperature range 85 - 130K where two structural phase transitions occur, and at pressures from 1 to 2643 bars. A number of unusual features were revealed and discussed as the possible signature of incommensurate behavior. The primary effect of the pressure was to alter the temperatures at which the phase transitions occurred. Contrary to the behavior expected, the transition temperature for the antiferrorotative transition has a negative pressure coefficient. The spin-lattice and spin-spin relaxation times for the ('35)Cl and ('37)Cl isotopes of the one dimensional XY system, PrCl(,3), were measured at 4.2K. The spin-lattice relaxation is exponential and dominated by magnetic dipole -dipole interactions. The spin-spin relaxation is non-exponential and dominated by electric quadrupolar interactions arising from the coupling of the electric dipole moment at the praseodymium site and the quadrupole moment of the chlorine ion. The temperature dependence of the spin-spin relaxation time was investigated. At 17.4 K both magnetic dipolar and electric

  20. Triple Quadrupole Versus High Resolution Quadrupole-Time-of-Flight Mass Spectrometry for Quantitative LC-MS/MS Analysis of 25-Hydroxyvitamin D in Human Serum.

    PubMed

    Geib, Timon; Sleno, Lekha; Hall, Rabea A; Stokes, Caroline S; Volmer, Dietrich A

    2016-08-01

    We describe a systematic comparison of high and low resolution LC-MS/MS assays for quantification of 25-hydroxyvitamin D3 in human serum. Identical sample preparation, chromatography separations, electrospray ionization sources, precursor ion selection, and ion activation were used; the two assays differed only in the implemented final mass analyzer stage; viz. high resolution quadrupole-quadrupole-time-of-flight (QqTOF) versus low resolution triple quadrupole instruments. The results were assessed against measured concentration levels from a routine clinical chemiluminescence immunoassay. Isobaric interferences prevented the simple use of TOF-MS spectra for extraction of accurate masses and necessitated the application of collision-induced dissociation on the QqTOF platform. The two mass spectrometry assays provided very similar analytical figures of merit, reflecting the lack of relevant isobaric interferences in the MS/MS domain, and were successfully applied to determine the levels of 25-hydroxyvitamin D for patients with chronic liver disease. Graphical Abstract ᅟ.

  1. Triple Quadrupole Versus High Resolution Quadrupole-Time-of-Flight Mass Spectrometry for Quantitative LC-MS/MS Analysis of 25-Hydroxyvitamin D in Human Serum

    NASA Astrophysics Data System (ADS)

    Geib, Timon; Sleno, Lekha; Hall, Rabea A.; Stokes, Caroline S.; Volmer, Dietrich A.

    2016-08-01

    We describe a systematic comparison of high and low resolution LC-MS/MS assays for quantification of 25-hydroxyvitamin D3 in human serum. Identical sample preparation, chromatography separations, electrospray ionization sources, precursor ion selection, and ion activation were used; the two assays differed only in the implemented final mass analyzer stage; viz. high resolution quadrupole-quadrupole-time-of-flight (QqTOF) versus low resolution triple quadrupole instruments. The results were assessed against measured concentration levels from a routine clinical chemiluminescence immunoassay. Isobaric interferences prevented the simple use of TOF-MS spectra for extraction of accurate masses and necessitated the application of collision-induced dissociation on the QqTOF platform. The two mass spectrometry assays provided very similar analytical figures of merit, reflecting the lack of relevant isobaric interferences in the MS/MS domain, and were successfully applied to determine the levels of 25-hydroxyvitamin D for patients with chronic liver disease.

  2. Continuous Quadrupole Magnetic Separation of Islets during Digestion Improves Purified Porcine Islet Viability

    PubMed Central

    Kumar Sajja, Venkata Sunil; Rizzari, Michael D.; Scott III, William E.; Kitzmann, Jennifer P.; Kennedy, David J.; Todd, Paul W.; Balamurugan, Appakalai N.; Hering, Bernhard J.

    2016-01-01

    Islet transplantation (ITx) is an emerging and promising therapy for patients with uncontrolled type 1 diabetes. The islet isolation and purification processes require exposure to extended cold ischemia, warm-enzymatic digestion, mechanical agitation, and use of damaging chemicals for density gradient separation (DG), all of which reduce viable islet yield. In this paper, we describe initial proof-of-concept studies exploring quadrupole magnetic separation (QMS) of islets as an alternative to DG to reduce exposure to these harsh conditions. Three porcine pancreata were split into two parts, the splenic lobe (SPL) and the combined connecting/duodenal lobes (CDL), for paired digestions and purifications. Islets in the SPL were preferentially labeled using magnetic microparticles (MMPs) that lodge within the islet microvasculature when infused into the pancreas and were continuously separated from the exocrine tissue by QMS during the collection phase of the digestion process. Unlabeled islets from the CDL were purified by conventional DG. Islets purified by QMS exhibited significantly improved viability (measured by oxygen consumption rate per DNA, p < 0.03) and better morphology relative to control islets. Islet purification by QMS can reduce the detrimental effects of prolonged exposure to toxic enzymes and density gradient solutions and substantially improve islet viability after isolation. PMID:27843954

  3. Continuous Quadrupole Magnetic Separation of Islets during Digestion Improves Purified Porcine Islet Viability.

    PubMed

    Weegman, Bradley P; Kumar Sajja, Venkata Sunil; Suszynski, Thomas M; Rizzari, Michael D; Scott Iii, William E; Kitzmann, Jennifer P; Mueller, Kate R; Hanley, Thomas R; Kennedy, David J; Todd, Paul W; Balamurugan, Appakalai N; Hering, Bernhard J; Papas, Klearchos K

    2016-01-01

    Islet transplantation (ITx) is an emerging and promising therapy for patients with uncontrolled type 1 diabetes. The islet isolation and purification processes require exposure to extended cold ischemia, warm-enzymatic digestion, mechanical agitation, and use of damaging chemicals for density gradient separation (DG), all of which reduce viable islet yield. In this paper, we describe initial proof-of-concept studies exploring quadrupole magnetic separation (QMS) of islets as an alternative to DG to reduce exposure to these harsh conditions. Three porcine pancreata were split into two parts, the splenic lobe (SPL) and the combined connecting/duodenal lobes (CDL), for paired digestions and purifications. Islets in the SPL were preferentially labeled using magnetic microparticles (MMPs) that lodge within the islet microvasculature when infused into the pancreas and were continuously separated from the exocrine tissue by QMS during the collection phase of the digestion process. Unlabeled islets from the CDL were purified by conventional DG. Islets purified by QMS exhibited significantly improved viability (measured by oxygen consumption rate per DNA, p < 0.03) and better morphology relative to control islets. Islet purification by QMS can reduce the detrimental effects of prolonged exposure to toxic enzymes and density gradient solutions and substantially improve islet viability after isolation.

  4. Factorial experimental designs elucidate significant variables affecting data acquisition on a quadrupole Orbitrap mass spectrometer.

    PubMed

    Randall, Shan M; Cardasis, Helene L; Muddiman, David C

    2013-10-01

    Instrument parameter values for a quadrupole Orbitrap mass spectrometer were optimized for performing global proteomic analyses. Fourteen factors were evaluated for their influence on data-dependent acquisition with an emphasis on both the rate of sequencing and spectral quality by maximizing two individually tested response variables (unique peptides and protein groups). Of the 14 factors, 12 factors were assigned significant contrast values (P < 0.05) for both response variables. Fundamentally, when optimizing parameters, a balance between spectral quality and duty cycle needs to be reached in order to maximize proteome coverage. This is especially true when using a data-dependent approach for sequencing complex proteomes. For example, maximum ion injection time, automatic gain control settings, and minimum threshold settings for triggering MS/MS isolation and activation all heavily influence ion signal, the number of spectra collected, and spectral quality. To better assess the effect these parameters have on data acquisition, all MS/MS data were parsed according to ion abundance by calculating the percent of the AGC target reached for each MS/MS event and then compared with successful peptide-spectrum matches. This proved to be an effective approach for understanding the effect of ion abundance on successful peptide-spectrum matches and establishing minimum ion abundance thresholds for triggering MS/MS isolation and activation.

  5. Dynamic collision-induced dissociation of peptides in a quadrupole ion trap mass spectrometer.

    PubMed

    Collin, Olivier L; Beier, Matthias; Jackson, Glen P

    2007-07-15

    The fragmentation of natural peptides using dynamic collision-induced dissociation (DCID), a novel fragmentation method for quadrupole ion traps, is demonstrated. Using leucine enkephalin as a diagnostic molecule, the fragmentation efficiencies and energetics of DCID are compared with other methods of collisional activation in ion traps such as conventional on-resonance excitation and high-amplitude short-time excitation (HASTE). A typical fragmentation efficiency of approximately 20% is achieved for DCID, which is significantly lower than conventional CID (maximum near 80%). Tandem mass spectra of two other peptides, substance P and oxidized insulin alpha-chain, demonstrate that product ion spectra for DCID are comparable to conventional or HASTE CID. Because DCID achieves fragmentation during the standard mass acquisition scan, no extra time is necessary for on-resonance excitation or product ion collection, so analysis times are reduced by a minimum of 10-15% depending on the scanning conditions. DCID therefore offers more tandem mass spectra per second than conventional methods of collisional activation, which could be highly advantageous for bottom-up proteomics separations.

  6. The use of the pairing-quadrupole connections in PQM for application in nuclear systems

    NASA Astrophysics Data System (ADS)

    Drumev, K. P.; Georgieva, A. I.

    2016-03-01

    Within the algebraic realization of the Pairing-plus-Quadrupole Model /PQM/ in the framework of the Elliott's SU(3) Model,we present some particular applications for realistic nuclear systems. The probability distribution of the SU(3) basis states within the isovector, isoscalar and total pairing eigenstates is obtained through a numerical diagonalization of the PQM Hamiltonian in each limit. This allows the investigation of the interplay between the pairing and quadrupole interactions in the Hamiltonian of the PQM, containing all of them as limiting cases. The relative strengths of the dynamically symmetric quadrupole-quadrupole interaction with the considered types of pairing interactions are investigated systematically for systems like the 20Ne.

  7. 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.

  8. 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.

  9. High-precision quadrupole moment reveals significant intruder component in 20 13 33Al ground state

    NASA Astrophysics Data System (ADS)

    Heylen, H.; De Rydt, M.; Neyens, G.; Bissell, M. L.; Caceres, L.; Chevrier, R.; Daugas, J. M.; Ichikawa, Y.; Ishibashi, Y.; Kamalou, O.; Mertzimekis, T. J.; Morel, P.; Papuga, J.; Poves, A.; Rajabali, M. M.; Stödel, C.; Thomas, J. C.; Ueno, H.; Utsuno, Y.; Yoshida, N.; Yoshimi, A.

    2016-09-01

    The electric quadrupole moment of the 20 13 33Al ground state, located at the border of the island of inversion, was obtained using continuous-beam β -detected nuclear quadrupole resonance (β -NQR). From the measured quadrupole coupling constant νQ=2.31 (4 ) MHz in an α -Al2O3 crystal, a precise value for the electric quadrupole moment is extracted: 33Al>Qs 141 (3 ) mb. A comparison with large-scale shell model calculations shows that 33Al has at least 50% intruder configurations in the ground state wave function, favoring the excitation of two neutrons across the N =20 shell gap. 33Al therefore clearly marks the gradual transition north of the deformed Na and Mg nuclei towards the normal Z ≥14 isotopes.

  10. A new technique of beam energy resolution by using only quadrupole magnets

    NASA Astrophysics Data System (ADS)

    Sarma, P. R.

    2003-08-01

    In the standard technique of beam energy resolution one uses the property of momentum dispersion by dipole magnets. It is shown that one can, alternatively, use three quadrupole magnets to select the beam momentum or energy. The lengths and magnetic fields of the quadrupoles can be adjusted to focus the particles of the required energy and simultaneously defocus the particles of higher or lower energies. For obtaining a very high resolving power one can use such triplets in cascade. The resolving powers of these are multiplicative, whereas in the case of dipoles one can use just two bending magnets for roughly doubling the resolving power. This method is different from the technique used in quadrupole mass filters where RF field is used in quadrupoles.

  11. 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.

  12. Iodine: Many Electrons and much to DISCUSS...THE Nuclear Quadrupole Coupling, Nuclear Spin-Rotation Conformational Analysis, and Structural Determination of 2-IODOBUTANE

    NASA Astrophysics Data System (ADS)

    Arsenault, Eric A.; Choi, Yoon Jeong; Obenchain, Daniel A.; Cooke, S. A.; Blake, Thomas A.; Novick, Stewart E.

    2016-06-01

    The rotational spectrum of 2-iodobutane (sec-butyl-iodide) has been collected from 5.5-16.5 GHz using jet-pulsed Fourier transform microwave spectroscopy on both broadband and Balle-Flygare cavity instruments. Transitions belonging to three unique conformers were observed, namley the gauche-, anti-, and gauche'- species. All four 13C isotopologues of the gauche-2-iodobutane were observed. The complete nuclear quadrupole coupling tensor of iodine has been determined for all conformers and 13C isotopologues. A comparison between these nuclear quadrupole coupling tensors and those of similar iodine-containing molecules will be presented. Changes in the quadrupole coupling of iodine upon isotopic substitution will also be discussed. Additionally, isotopic substitution in conjunction with ab initio calculations allowed for both an r_s and r_0 structural analysis of gauche-2-iodobutane. Brown, G. G.; Dian, B. C.; Douglass, K. O.; Geyer, S. M.; Shipman, S. T.; Pate, B. H. Review of Scientific Instruments 2008, 79, 053103. Balle, T.; Flygare, W. Review of Scientific Instruments 1981, 52, 33-45.

  13. 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

  14. 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

  15. 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.

  16. Effects of Coulomb quadrupole excitation in heavy-ion reactions

    NASA Astrophysics Data System (ADS)

    Cheoun, Myung-Ki; Choi, K. S.; Kim, K. S.; Kim, T. H.; So, W. Y.

    2016-09-01

    For 12C + 184W, 18O + 184W, and 20Ne + 208Pb systems, we investigate the suppression of the ratios P E = σ el/ σ RU by using the Coulomb quadrupole excitation (CQE) potentials. In order to explain the effect of the CQE potentials, we first use a well-known Love's CQE potential, and reproduce the experimental P E data well by using this potential. We also introduce a simple CQE potential written as W CQE( r) = - W P / r n , which is much simpler than the conventional Love's potential, to investigate the suppression of the P E ratios. Using this potential, we perform a χ2 analysis to find the adjustable parameter n, then, we find that the best fit parameters n ≈ 5 is close to the lowest order term, 1/ r 5. Consequently, we find that using the simple CQE potential explains the experimental P E data and that the ratio P E depends on the n values sensitively.

  17. Modal response of 4-rod type radio frequency quadrupole linac

    SciTech Connect

    Chatterjee, Avik; Mahapatra, Abhijit; Mondal, Manas; Chakrabarti, Alok

    2009-10-15

    This paper deals with the analysis and experimental study of natural frequencies of vibration of a 4-rod type radio frequency quadrupole (RFQ) linear accelerator. The eigenvalue analysis of the structure has been done both analytically (multispan beam concept) as well as using blocked Lanczos eigenvalue finite element solver with an ability to extract the rigid body modes. This has been done in the mechanical design phase to find the level of agreement between the output of simplified analytical analysis results and the output of a commercial finite element method (FEM) solver, since a full scale RFQ structure is too complex to handle analytically. Experimental validation of the analysis results has been done on the physical 1.7 m RFQ at the installation site. The experimental data obtained were later analyzed and found to be in close agreement with the predicted frequencies in the lower frequency ranges. It gets more and more deviated in the higher frequency ranges. Also some frequencies were observed during experimentation, which were not found in the finite element analysis results. The source of those frequencies are to be further investigated as it may play a predominant role in the design high quality factor beam line cavities for higher operational efficiency.

  18. Miniature mass spectrometer systems based on a microengineered quadrupole filter.

    PubMed

    Malcolm, Andrew; Wright, Steven; Syms, Richard R A; Dash, Neil; Schwab, Marc-André; Finlay, Alan

    2010-03-01

    Two miniature mass spectrometer systems based on a microengineered quadrupole mass filter have been developed. One of the instruments has a footprint of 27 cm x 20 cm and is intended for laboratory use when space is at a premium. The other is portable and intended for use in the field. It is battery powered, weighs 14.9 kg, and is housed in a rugged case. This is the first example of a portable mass spectrometer incorporating an analyzer fabricated using microelectromechanical systems (MEMS) techniques. The starting material for construction of the filters is a bonded silicon on insulator substrate, which is selectively etched using batch processing techniques to form coupling optics and springs that accurately hold 0.5 mm diameter stainless steel rods in the required geometry. Assembled filters measure 35 mm x 6 mm x 1.5 mm and are mounted, together with an ion source and channeltron detector, in small, interchangeable cartridges, which plug into a 220 cm(3) vacuum chamber. Recovery from accidental contamination or when servicing is required can be achieved within 5-10 min, as the cartridge is easily exchanged with a spare. A potential application to environmental monitoring has been investigated. The headspace above water spiked with dibutyl mercaptan was sampled with a solid phase microextraction (SPME) fiber, which was then injected directly into the vacuum chamber of the mass spectrometer. Using this method, the limit of detection was found to be approximately 5 ppm for a 15 s sampling period.

  19. Hyperfine and nuclear quadrupole coupling in chlorine and fluorine dioxides

    NASA Astrophysics Data System (ADS)

    Fernández, Berta; Christiansen, Ove; Jørgensen, Poul; Byberg, Jørgen; Gauss, Jürgen; Ruud, Kenneth

    1997-02-01

    The hyperfine and nuclear quadrupole coupling tensors have been calculated for the two chlorine dioxide isomers OClO and ClOO and for fluorine dioxide FOO. The coupled-cluster singles and doubles (CCSD) approach with a perturbative treatment of triple excitations [CCSD(T)] has been used and basis saturation has been investigated. For the symmetric isomer OClO close agreement is obtained with the accurate and detailed experimental data. For FOO a geometry optimization as well as a comparison of calculated and experimental hyperfine coupling tensors suggest a shorter F-O bond length than that obtained experimentally. For the isomer ClOO, calculations have been carried out at the theoretical equilibrium geometry determined by Peterson and Werner and at the geometry proposed by Byberg for the matrix isolated molecule. The hyperfine coupling tensors obtained at these two geometries are substantially different, but the estimated accuracy of the calculations is not high enough to allow a determination of the geometry of ClOO from the hyperfine data.

  20. "Fast Excitation" CID in Quadrupole Ion Trap Mass Spectrometer

    SciTech Connect

    Murrell, J.; Despeyroux, D.; Lammert, Stephen {Steve} A; Stephenson Jr, James {Jim} L; Goeringer, Doug

    2003-01-01

    Collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer is usually performed by applying a small amplitude excitation voltage at the same secular frequency as the ion of interest. Here we disclose studies examining the use of large amplitude voltage excitations (applied for short periods of time) to cause fragmentation of the ions of interest. This process has been examined using leucine enkephalin as the model compound and the motion of the ions within the ion trap simulated using ITSIM. The resulting fragmentation information obtained is identical with that observed by conventional resonance excitation CID. ''Fast excitation'' CID deposits (as determined by the intensity ratio of the a{sub 4}/b{sub 4} ion of leucine enkephalin) approximately the same amount of internal energy into an ion as conventional resonance excitation CID where the excitation signal is applied for much longer periods of time. The major difference between the two excitation techniques is the higher rate of excitation (gain in kinetic energy) between successive collisions with helium atoms with ''fast excitation'' CID as opposed to the conventional resonance excitation CID. With conventional resonance excitation CID ions fragment while the excitation voltage is still being applied whereas for ''fast excitation'' CID a higher proportion of the ions fragment in the ion cooling time following the excitation pulse. The fragmentation of the (M + 17H){sup 17+} of horse heart myoglobin is also shown to illustrate the application of ''fast excitation'' CID to proteins.

  1. 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.

  2. Electric Quadrupole Transition Measurements of Hydrogen Molecule with High Precision

    NASA Astrophysics Data System (ADS)

    Cheng, Cun-Feng; Wang, Jin; Tan, Yan; Liu, An-Wen; Hu, Shui-Ming

    2013-06-01

    Molecular hydrogen is the most fundamental, and the only neutral molecule expected to be both calculated and measured with extremely high accuracy. High-precision measurements of its spectroscopy, especially the levels at the electric ground state, play an important role in the examination of precise quantum chemistry calculations and some fundamental physical constants. In the infrared region, H_2, being a homonuclear diatomic molecule, only has very weak electric quadrupole transitions. We established a new spectroscopy approach with ultra-high precision and sensitivity as well, based on a laser-locked cavity ring-down spectrometer. An equivalent absorption path-length of thousands of kilometers and a frequency precision of 10^{-5} cm^{-1} have been achieved. Ro-vibrational spectra of the second overtone of H_2 have been recorded. The obtained results will provide a direct examination of the high-accuracy quantum theory. It also shades light on the determination of fundamental physical constants such as the electron/proton mass ratio in a molecular system.

  3. Polarization enhanced Nuclear Quadrupole Resonance with an atomic magnetometer

    NASA Astrophysics Data System (ADS)

    Malone, Michael W.; Barrall, Geoffrey A.; Espy, Michelle A.; Monti, Mark C.; Alexson, Dimitri A.; Okamitsu, Jeffrey K.

    2016-05-01

    Nuclear Quadrupole Resonance (NQR) has been demonstrated for the detection of 14-N in explosive compounds. Application of a material specific radio-frequency (RF) pulse excites a response typically detected with a wire- wound antenna. NQR is non-contact and material specific, however fields produced by NQR are typically very weak, making demonstration of practical utility challenging. For certain materials, the NQR signal can be increased by transferring polarization from hydrogen nuclei to nitrogen nuclei using external magnetic fields. This polarization enhancement (PE) can enhance the NQR signal by an order of magnitude or more. Atomic magnetometers (AM) have been shown to improve detection sensitivity beyond a conventional antenna by a similar amount. AM sensors are immune to piezo-electric effects that hamper conventional NQR, and can be combined to form a gradiometer for effective RF noise cancellation. In principle, combining polarization enhancement with atomic magnetometer detection should yield improvement in signal-to-noise ratio that is the product of the two methods, 100-fold or more over conventional NQR. However both methods are even more exotic than traditional NQR, and have never been combined due to challenges in operating a large magnetic field and ultra-sensitive magnetic field sensor in proximity. Here we present NQR with and without PE with an atomic magnetometer, demonstrating signal enhancement greater than 20-fold for ammonium nitrate. We also demonstrate PE for PETN using a traditional coil for detection with an enhancement factor of 10. Experimental methods and future applications are discussed.

  4. 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.

  5. Ion mobility analyzer - quadrupole mass spectrometer system design

    NASA Astrophysics Data System (ADS)

    Cuna, C.; Leuca, M.; Lupsa, N.; Mirel, V.; Bocos-Bintintan, V.; Cuna, Stela; Cosma, V.; Tusa, Florina

    2009-08-01

    Because of their extremely high sensitivity for chemicals with elevated electronegativity or high proton affinity the ion mobility analysers are ideal for the ultra-trace detection of toxic or explosive chemicals, most of these situated often at concentration levels of sub-ppb (parts-per-billion). Ion mobility spectrometers (IMS) can be used to identify illicit drugs or environmental pollutants. Since resolution of an IMS is relatively low, to achieve an accurate identification of target analyte it is recommended to couple the IMS with a quadrupole mass spectrometer (QMS) or a time of flight mass spectrometer, acquiring in this way confirmatory information. This coupling is made through a specific interface. In this paper, an experimental model of such a tandem instrument, IMS-QMS is described. Accomplishment of this general purpose will be done, overcoming a series of specific issues. This implies the solving, using innovative solutions, of a series of complex issues: ensuring the stability of the ions beam generated by ion source; transfer with a good efficiency of the ionic current from IMS analyser to QMS; and realization of a special electronic circuitry which will be able to detect both positive and negative ions.

  6. 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.

  7. Modal response of 4-rod type radio frequency quadrupole linac.

    PubMed

    Chatterjee, Avik; Mahapatra, Abhijit; Mondal, Manas; Chakrabarti, Alok

    2009-10-01

    This paper deals with the analysis and experimental study of natural frequencies of vibration of a 4-rod type radio frequency quadrupole (RFQ) linear accelerator. The eigenvalue analysis of the structure has been done both analytically (multispan beam concept) as well as using blocked Lanczos eigenvalue finite element solver with an ability to extract the rigid body modes. This has been done in the mechanical design phase to find the level of agreement between the output of simplified analytical analysis results and the output of a commercial finite element method (FEM) solver, since a full scale RFQ structure is too complex to handle analytically. Experimental validation of the analysis results has been done on the physical 1.7 m RFQ at the installation site. The experimental data obtained were later analyzed and found to be in close agreement with the predicted frequencies in the lower frequency ranges. It gets more and more deviated in the higher frequency ranges. Also some frequencies were observed during experimentation, which were not found in the finite element analysis results. The source of those frequencies are to be further investigated as it may play a predominant role in the design high quality factor beam line cavities for higher operational efficiency.

  8. Gyrokinetic equilibrium and stability in quadrupole tandem mirrors

    SciTech Connect

    Bulmer, R.H.; Kaiser, T.B.; Nevins, W.M.; Newcomb, W.A.; Pearlstein, L.D.; Strauss, H.R.; Wollman, S.; Wakatani, M.

    1982-08-02

    This paper discusses recent theoretical work on the equilibrium and stability of quadrupole tandem mirrors in the paraxial limit. It reviews calculations of three-dimensional equilibria by means of a ..beta..-expansion technique which lead to an understanding of the important role played by parallel currents and the corollary importance of careful design of the structure of the vacuum geodesic curvature. The previously predicted scaling with central-cell length of the finite-..beta.. distortion of vacuum flux surfaces is shown to saturate because of finite orbit effects. An adaptation to tandem geometries of the reduced MHD technique for calculating high-..beta.. three-dimensional equilibria is described. This approach uses the paraxial expansion to resolve the time-dependent relaxation to equilibrium into three distinct timescales on which the motion can be followed independently. Regarding stability, it is shown that kinetic effects suppress ballooning modes of short-to-moderate perpendicular wavelength; in the limit that such effects are dominant only rigid modes are possible. The stability of the latter modes is investigated within the context of the energy principle. Results of equilibrium and stability calculations for the TMX-U and MFTF-B experiments at Livermore are presented.

  9. Newly developed apparatus for calibration of quadrupole mass spectrometer

    NASA Astrophysics Data System (ADS)

    Meng, Dong; Yongjun, Cheng; Detian, Li; Wenjun, Sun; Lan, Zhao; Meiru, Guo; Yongjun, Wang; Huzhong, Zhang; Yanwu, Li; Gang, Li

    2017-01-01

    In this paper, a new calibration apparatus has been developed for calibrating quadrupole mass spectrometer (QMS) from 10-8 Pa to 10-2 Pa for He, N2 and Ar. Based on the apparatus, two calibration methods are introduced to generate standard pressure P i ‧ (or P i ″) of lower than 10-2 Pa, which are named as ‘the SRG measurement method’ and ‘the CDG measurement method’. The SRG measurement method can generate a standard pressure range from 10-8 Pa to 10-5 Pa, and the CDG measurement method can generate a standard pressure range from 10-5 Pa to 10-2 Pa. A molecular flow condition is determined and a QMS is calibrated by the two methods using single gas and mixture gas. The gas flow through the small tube and orifice realizes molecular flow at an upstream pressure of less than 70 Pa. The sensitivities calibration results with the two methods agree well, and the difference is less than 3%. The sensitivity calibrated with single gas is different from that calibrated with mixture gas. Obtained results are roughly consistent with those of previous studies.

  10. On the formation of the South Pacific quadrupole mode

    NASA Astrophysics Data System (ADS)

    Zheng, Jian; Wang, Faming

    2016-08-01

    The formation process of the South Pacific (SP) quadrupole (SPQ) mode was investigated in this study based on observations and reanalysis data. The SPQ is the dominant mode of the sea surface temperature (SST)-surface wind covariability in the SP after removing the ENSO-related signals. The positive phase of the SPQ is characterized by a warm SST anomaly (SSTA) west of the South American coast, a cool SSTA in its southwest, a positive SSTA southeast of New Zealand, and a negative SSTA off the southeast coast of Australia, overlain by cyclonic wind anomalies. The anomalous cyclonic winds weaken the mean southeast trade winds in the southeast SP and the westerlies in the high latitudes of the SP, increasing the SSTAs at the two positive poles through decreased evaporation and latent heat flux (LHF) loss. The southeast wind anomalies advect dry and cold air to the negative pole in the central SP, which reduces the SSTA there by increasing the LHF loss. Off the southeast coast of Australia, the southwest wind anomalies induce equatorward Ekman currents and advect cold water. The resulting oceanic horizontal advection is the main contributor to the negative SSTAs there. In addition to the above processes, cloud cover change can enhance the initial SSTAs in the southeast SP by affecting shortwave radiation. The decay of the SPQ is mainly due to LHF changes.

  11. Evaluation of quadrupole-time-of-flight mass spectrometry in comprehensive two-dimensional gas chromatography.

    PubMed

    Mitrevski, Blagoj; Marriott, Philip J

    2014-10-03

    Quadrupole time-of-flight mass spectrometry (Q-TOFMS) has been evaluated with respect to its applicability in comprehensive two-dimensional gas chromatography (GC×GC). At a maximum acquisition frequency, while approximately 50 full accurate mass spectra on disk were acquired per s (50Hz) in scan mode, the sampling rate in target mode (MS/MS) was strongly dependent on the number of target ions selected. The number of selected precursor ions per time window proportionally decreased the acquisition rate for each ion; one precursor ion ≅31.35Hz; two ions ≅16.68Hz; and for 8 precursor ions, a sampling rate of just 4.18Hz was found. When Q-TOFMS was used in simultaneous mode, where in addition to the acquisition of target ion MS/MS signals, it also collects the full mass spectrum, sampling rates were even lower. It is demonstrated that Q-TOFMS generates sufficient data points over each peak in GC×GC operation in scan mode using TOFMS acquisition only, or is able to collect sufficient data points for relatively wide chromatographic peaks (≥600ms) in the target mode (MS/MS), however only if one or two precursor ions are selected per time window. Mass accuracy was found to perform within specification (<5ppm), even for the fastest acquisition operation (50Hz). Spectral deconvolution is demonstrated to work better in GC×GC than in 1D GC mode. Data visualisation in target GC×GC mode presents difficulties when there are overlapping target windows comprising different numbers of precursor ions.

  12. Detecting body cavity bombs with nuclear quadrupole resonance

    NASA Astrophysics Data System (ADS)

    Collins, Michael London

    Nuclear Quadrupole Resonance (NQR) is a technology with great potential for detecting hidden explosives. Past NQR research has studied the detection of land mines and bombs concealed within luggage and packages. This thesis focuses on an NQR application that has received less attention and little or no publicly available research: detecting body cavity bombs (BCBs). BCBs include explosives that have been ingested, inserted into orifices, or surgically implanted. BCBs present a threat to aviation and secure facilities. They are extremely difficult to detect with the technology currently employed at security checkpoints. To evaluate whether or not NQR can be used to detect BCBs, a computational model is developed to assess how the dielectric properties of biological tissue affect the radio frequency magnetic field employed in NQR (0.5-5MHz). The relative permittivity of some biological tissue is very high (over 1,000 at 1MHz), making it conceivable that there is a significant effect on the electromagnetic field. To study this effect, the low-frequency approximation known as the Darwin model is employed. First, the electromagnetic field of a coil is calculated in free space. Second, a dielectric object or set of objects is introduced, and the free-space electric field is modified to accommodate the dielectric object ensuring that the relevant boundary conditions are obeyed. Finally, the magnetic field associated with the corrected electric field is calculated. This corrected magnetic field is evaluated with an NQR simulation to estimate the impact of dielectric tissue on NQR measurements. The effect of dielectric tissue is shown to be small, thus obviating a potential barrier to BCB detection. The NQR model presented may assist those designing excitation and detection coils for NQR. Some general coil design considerations and strategies are discussed.

  13. Two Alternate High Gradient Quadrupoles; An Upgraded Tevatron IR and A"Pipe" Design

    SciTech Connect

    McInturff, A.D.; Oort, J.M. van; Scanlan, R.M.

    1995-04-01

    With the U.S. cancellation of the SSC project, the only large approved hadron accelerator project is CERN's LHC. One of the more critical elements in the performance of a collider is the quadrupole lens at the beam collision points. These quadrupoles, usually referred to as the 'insertion quads' normally form a set of triplets around the interaction region. Their focal power directly affects the luminosity available at the crossing point In order to achieve as high a gradient as possible, the CERN design team has proposed a very efficient high gradient quadrupole which is based on a graded four-layer winding structure. At Fermilab's Tevatron, an upgraded two layer winding quadrupole has been in operation since 1989, and has provided a 50% higher gradient than its predecessor. The quadrupole was basically state of the art when it was designed in 1985. Since then however, improvements have been made in cabling, conductor perfonnance, etc. Naturally, operation of a modernized version of this .design can provide higher capabilities. This improved two layer design can serve as an alternative to the more intricate graded four layer design now envisioned for the LHC, provided it can obtain the proposed gradient. A high gradient quadrupole with a 'pipe' layout can be considered as a possible candidate for future large collider insertion regions. It is possible to fine-tune the design to obtain a good field-quality, the conductor is well cooled in case of a large radiation heat load, and the overall structure is smaller than a conventional quadrupole with a comparable field gradient.

  14. Energy balance and deformation at scission in 240Pu fission

    NASA Astrophysics Data System (ADS)

    Caamaño, Manuel; Farget, Fanny

    2017-07-01

    The experimental determination of the total excitation energy, the total kinetic energy, and the evaporation neutron multiplicity of fully identified fragments produced in transfer-induced fission of 240Pu, combined with reasonable assumptions, permits to extract the intrinsic and collective excitation energy of the fragments as a function of their atomic number, along with their quadrupole deformation and their distance at scission. The results show that the deformation increases with the atomic number, Z, except for a local maximum around Z = 44 and a minimum around Z = 50, associated with the effect of deformed shells at Z ∼ 44, N ∼ 64, and spherical shells in 132Sn, respectively. The distance between the fragments also shows a minimum around Z1 = 44, Z2 = 50, suggesting a mechanism that links the effect of structure with the length of the neck at scission.

  15. 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.

  16. Measurements of magnetization multipoles in four centimeter quadrupoles for the SSC

    SciTech Connect

    Green, M.A.; Barale, P.J.; Benjegerdes, R.W.; Gilbert, W.S.; Green, M.I.; Scanlan, R.M.; Sopher, J.; Taylor, C.E.

    1991-06-01

    Higher multipoles due to magnetization of the superconductor in superconducting dipole and quadrupole magnets has been observed in over twenty years. This report presents measurements of the 12 pole and 20 pole multipoles in a model one-meter long four-centimeter bore SSC type quadrupole built at the Lawrence Berkeley Laboratory (LBL). The measurements were compared with calculations of the field structure using magnetization theory. Good agreement was observed between the measured multipoles and the calculated multipoles. Under conditions equivalent to injection into the SSC at an energy of 2 TeV, about 1.0 unit of 12 pole was observed and 0.05 units of 20 pole was observed. (One unit of field error is a field error of one part in ten thousand). Magnetization multipole measurements were also done on the first full length (5 meter) SSC quadrupole prototype. Measurements of flux creep decay were made on three one meter quadrupoles and the first five meter long quadrupole. 7 refs., 9 figs.

  17. Nuclear quadrupole interaction of highly polarized gas phase 131Xe with a glass surface

    NASA Astrophysics Data System (ADS)

    Butscher, R.; Wäckerle, G.; Mehring, M.

    1994-05-01

    We report nuclear magnetic resonance (NMR) experiments on 131Xe (I=3/2) gas-phase atoms which exhibit nuclear quadrupole interaction with the surface of the sample cell. Nuclear quadrupole coupling constants and quadrupole relaxation rates are obtained from the time-domain signal of the freely precessing nuclear magnetization in weak magnetic fields. The nuclear spin species is polarized by spin-exchange collisions with optically pumped ground-state spins of Rb gas atoms. The Rb atoms also present in the sample are used as a magnetometer to probe the free-induction decay of the nuclear-spin ensemble. The temperature dependence of both the effective quadrupole splittings and the relaxation rates are explained by a model for the surface interactions of a Xe atom adsorbed on the glass surface. The desorption is thermally activated with an activation energy of EA=0.12 eV. The surface diffusion of an adsorbed atom is characterized by an activation energy ED for thermally activated hopping between neighboring surface sites. Both energies enter the spectral density function governing wall-induced nuclear quadrupole relaxation. Our experimental results lead to the conclusion that they are on the same order of magnitude.

  18. Aharonov–Anandan quantum phases and Landau quantization associated with a magnetic quadrupole moment

    SciTech Connect

    Fonseca, I.C.; Bakke, K.

    2015-12-15

    The arising of geometric quantum phases in the wave function of a moving particle possessing a magnetic quadrupole moment is investigated. It is shown that an Aharonov–Anandan quantum phase (Aharonov and Anandan, 1987) can be obtained in the quantum dynamics of a moving particle with a magnetic quadrupole moment. In particular, it is obtained as an analogue of the scalar Aharonov–Bohm effect for a neutral particle (Anandan, 1989). Besides, by confining the quantum particle to a hard-wall confining potential, the dependence of the energy levels on the geometric quantum phase is discussed and, as a consequence, persistent currents can arise from this dependence. Finally, an analogue of the Landau quantization is discussed. -- Highlights: •Scalar Aharonov–Bohm effect for a particle possessing a magnetic quadrupole moment. •Aharonov–Anandan quantum phase for a particle with a magnetic quadrupole moment. •Dependence of the energy levels on the Aharonov–Anandan quantum phase. •Landau quantization associated with a particle possessing a magnetic quadrupole moment.

  19. Dynamics of extended bodies with spin-induced quadrupole in Kerr spacetime: generic orbits

    NASA Astrophysics Data System (ADS)

    Han, Wen-Biao; Cheng, Ran

    2017-03-01

    We discuss motions of extended bodies in Kerr spacetime by using Mathisson-Papapetrou-Dixon equations. We firstly solve the conditions for circular orbits, and calculate the orbital frequency shift due to the mass quadrupoles. The results show that we need not consider the spin-induced quadrupoles in extreme-mass-ratio inspirals for space-based gravitational wave detectors. We quantitatively investigate the temporal variation of rotational velocity of the extended body due to the coupling of quadrupole and background gravitational field. For generic orbits, we numerically integrate the Mathisson-Papapetrou-Dixon equations for evolving the motion of an extended body orbiting a Kerr black hole. By comparing with the monopole-dipole approximation, we reveal the influences of quadrupole moments of extended bodies on the orbital motion and chaotic dynamics of extreme-mass-ratio systems. We do not find any chaotic orbits for the extended bodies with physical spins and spin-induced quadrupoles. Possible implications for gravitational wave detection and pulsar timing observation are outlined.

  20. Rotating dipole and quadrupole field for a multiple cathode system

    SciTech Connect

    Chang, X.; Ben-Zvi, I.; Kewisch, J.; Litvinenko, V.; Meng, W.; Pikin, A.; Ptitsyn, V.; Rao, T.; Sheehy, B.; Skarita, J.; Wang, E.; Wu, Q.; Xin, T.

    2011-03-28

    A multiple cathode system has been designed to provide the high average current polarized electron bunches for the future electron-ion collider eRHIC [1]. One of the key research topics in this design is the technique to generate a combined dipole and quadrupole rotating field at high frequency (700 kHz). This type of field is necessary for combining bunches from different cathodes to the same axis with minimum emittance growth. Our simulations and the prototype test results to achieve this will be presented. The future eRHIC project, next upgrade of EHIC, will be the first electron-heavy ion collider in the world. For polarized-electron and polarized proton collisions, it requires a polarized electron source with high average current ({approx}50 mA), short bunch ({approx}3 mm), emittance of about 20 {micro}m and energy spread of {approx}1% at 10 MeV. The state-of-art polarized electron cathode can generate average current of about more than 1 mA, but much less than 50 mA. The current is limited by the quantum efficiency, lifetime, space charge and ultra-high vacuum requirement of the polarized cathode. A possible approach to achieve the 50 mA beam is to employ multiple cathodes, such as 20 cathodes, and combine the multiple bunched beams from cathodes to the same axis. We name it as 'Gatling gun' because its operations bear similarity to a multi-barrel Gatling gun. The electron spin direction is not affected by electric field but will follow to the direction of the magnetic bending. This requires that, to preserve the spin polarization from cathode, the fixed bending field after the solenoid and the rotating bending field in combiner must be either a pair of electric bendings or a pair of magnetic bendings. We choose the scheme with a pair of magnetic bendings because it is much easier than the scheme with a pair of electric bendings at our 200 keV electron energy level.

  1. Simulation of Ions Confined by Quadrupole Electric Fields

    NASA Astrophysics Data System (ADS)

    Cummings, Michael David

    Computer simulations are routinely used to develop physical insight into ionic systems confined by static and time-varying quadrupole electric fields. However, after nearly 30 years of numerical exploration, three questions remain: which numerical techniques produce accurate simulations for the least computational expense? How can thermal equilibrium initial conditions be generated? How should temperature be calculated? Trapped ion simulations generally employ molecular dynamics techniques, where ion trajectories are numerically calculated at discrete points in time. While many numerical methods have been applied to these systems, it is unclear which technique is fastest or what time-step is required. In this work, the computational speed of and time-step for 11 commonly used techniques are assessed through analysis of four numerical error components. The most rapid method and required step-size depend strongly on the system parameters, with any one of the Beeman, Gear6, 5th-order Adams-Bashforth-Moulton, or 4th-order Runge-Kutta algorithms proving most appropriate. The 11 algorithms are then applied to a realistic multi-ion system and verify that the four tests accurately predict the required step size. When equilibrium properties are desired, simulations should commence from initial conditions that conform closely to thermal equilibrium; however little has been published on initial condition generation and assessment for the multi-ion system. A method is presented for generating thermal equilibrium via laser cooling and recoil heating, a ramp-down stage, where the heating and cooling are gradually reduced, and an equilibration phase where the ensemble is evolved under only the trapping forces. Furthermore, it is demonstrated that thermal equilibrium can be assessed using well-known tests of distribution normality. When time-varying fields are present, temperature calculation becomes difficult, as the ion motion contains both thermal and nonthermal components. The

  2. Electrons in a positive-ion beam with solenoid or quadrupole magnetic transport

    SciTech Connect

    Molvik, A.W.; Kireeff Covo, M.; Cohen, R.; Coleman, J.; Sharp, W.; Bieniosek, F.; Friedman, A.; Roy, P.K.; Seidl, P.; Lund, S.M.; Faltens, A.; Vay, J.L.; Prost, L.

    2007-06-04

    The High Current Experiment (HCX) is used to study beam transport and accumulation of electrons in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam transport through and accumulation of electrons in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling electron cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current transport limits are reliable, in the absence of electrons. At the other extreme, reversing electrode biases with the solenoid transport effectively traps electrons; or, in quadrupole magnets, grounding the suppressor electrode allows electron emission from the end wall to flood the beam, in both cases producing significant degradation in the beam.

  3. Electrons in a Positive-Ion Beam with Solenoid or Quadrupole Magnet Transport

    SciTech Connect

    Molvik, A W; Cohen, R H; Friedman, A; Covo, M K; Lund, S M; Sharp, W M; Seidl, P A; Bieniosek, F M; Coleman, J E; Faltens, A; Roy, P K; Vay, J L; Prost, L

    2007-06-01

    The High Current Experiment (HCX) is used to study beam transport and accumulation of electrons in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam transport through and accumulation of electrons in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling electron cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current transport limits are reliable, in the absence of electrons. At the other extreme, reversing electrode biases with the solenoid transport effectively traps electrons; or, in quadrupole magnets, grounding the suppressor electrode allows electron emission from the end wall to flood the beam, in both cases producing significant degradation in the beam.

  4. A Superstrong Adjustable Permanent Magnet for the Final Focus Quadrupole in a Linear Collider

    SciTech Connect

    Mihara, T.

    2004-12-06

    A super strong permanent magnet quadrupole (PMQ) was fabricated and tested. It has an integrated strength of 28.5T with overall length of 10 cm and a 7mm bore radius. The final focus quadrupole of a linear collider needs a variable focal length. This can be obtained by slicing the magnet into pieces along the beamline direction and rotating these slices. But this technique may lead to movement of the magnetic center and introduction of a skew quadrupole component when the strength is varied. A ''double ring structure'' can ease these effects. A second prototype PMQ, containing thermal compensation materials and with a double ring structure, has been fabricated. Worm gear is selected as the mechanical rotating scheme because the double ring structure needs a large torque to rotate magnets. The structure of the second prototype PMQ is shown.

  5. Test results of the LARP Nb$$_3$$Sn quadrupole HQ03a

    DOE PAGES

    DiMarco, J.; G. Ambrosio; Chlachidze, G.; ...

    2016-03-09

    The US LHC Accelerator Research Program (LARP) has been developingmore » $$Nb_3Sn$$ quadrupoles of progressively increasing performance for the high luminosity upgrade of the Large Hadron Collider. The 120 mm aperture High-field Quadrupole (HQ) models are the last step in the R&D phase supporting the development of the new IR Quadrupoles (MQXF). Three series of HQ coils were fabricated and assembled in a shell-based support structure, progressively optimizing the design and fabrication process. The final set of coils consistently applied the optimized design solutions, and was assembled in the HQ03a model. Furthermore, this paper reports a summary of the HQ03a test results, including training, mechanical performance, field quality and quench studies.« less

  6. Test results of the LARP Nb$_3$Sn quadrupole HQ03a

    SciTech Connect

    DiMarco, J.; G. Ambrosio; Chlachidze, G.; Bossert, R.; Holik, T.; Orris, D.; Stoynev, S.; Strauss, T.; Sylvester, C.; Tartaglia, M.; Yu, M.; Anerella, M.; Ghosh, A.; Schmalzle, J.; Wanderer, P.; Borgnolutti, F.; Cheng, D. W.; Dietderich, D.; Felice, H.; Pan, H.; Godeke, A.; Hafalia, A. R.; Marchevsky, M.; Sabbi, G.; Salmi, T.; Wang, X. R.; Ferracin, P.; Bajas, H.; Ravaioli, E.; Todesco, E.

    2016-03-09

    The US LHC Accelerator Research Program (LARP) has been developing $Nb_3Sn$ quadrupoles of progressively increasing performance for the high luminosity upgrade of the Large Hadron Collider. The 120 mm aperture High-field Quadrupole (HQ) models are the last step in the R&D phase supporting the development of the new IR Quadrupoles (MQXF). Three series of HQ coils were fabricated and assembled in a shell-based support structure, progressively optimizing the design and fabrication process. The final set of coils consistently applied the optimized design solutions, and was assembled in the HQ03a model. Furthermore, this paper reports a summary of the HQ03a test results, including training, mechanical performance, field quality and quench studies.

  7. Calculations and measurements for the SLAC SLC positron return quadrupole magnet

    SciTech Connect

    Early, R.A.; Cobb, J.K.

    1986-09-01

    The three-dimensional magnetostatic computer program TOSCA, running on the NMFECC CRAY X-MP computer, was used to compute the integral of gradient length for the SLC type QT4 positron return line quadrupole magnet. Since the bore diameter of the magnet is 12.7 centimeters, and the length is only 10.16 centimeters, three dimensional effects are important. POISSON calculations were done on a two-dimensional model to obtain magnetic shimming which assured enough positive twelve pole to offset end effects, while TOSCA was used to estimate the effective length of the quadrupole. No corrections were required on the magnet as built. Measurements showed that the required integrated gradient was achieved for the given current, and that integrated higher harmonics were generally less than 0.1% of the quadrupole component.

  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. Measurement of Electric Quadrupole Moments for 31Al Using Spin Polarized RI Beams

    SciTech Connect

    Nagae, D.; Asahi, K.; Takemura, M.; Takase, K.; Uchida, M.; Shimada, K.; Arai, T.; Inoue, T.; Kagami, S.; Hatakeyama, N.; Ueno, H.; Kameda, D.; Yoshimi, A.; Sugimoto, T.; Nagatomo, T.; Kobayashi, Y.

    2007-06-13

    The electromagnetic moment is a sensitive probe to investigate microscopic structure. In order to measure the electromagnetic moment, {beta}-NMR and {beta}-NQR methods are employed taking advantage of the fragment spin polarization produced by the fragmentation reaction. The measurement of the electric quadrupole moment for ground-state 31Al has been been carried out by {beta}-NQR method. Spin-polarized 31Al nuclei were obtained from the fragmentation of 40Ar projectiles, and were implanted in {alpha}-Al2O3 stopper. The electric quadrupole moment was deduced from the measured quadrupole coupling constant. The obtained value is |Q(31Al)| 104(9) e{center_dot}mb.

  10. Antimagnetic rotation and sudden change of electric quadrupole transition strength in 143Eu

    NASA Astrophysics Data System (ADS)

    Rajbanshi, S.; Roy, S.; Nag, Somnath; Bisoi, Abhijit; Saha, S.; Sethi, J.; Bhattacharjee, T.; Bhattacharyya, S.; Chattopadhyay, S.; Gangopadhyay, G.; Mukherjee, G.; Palit, R.; Raut, R.; Saha Sarkar, M.; Singh, A. K.; Trivedi, T.; Goswami, A.

    2015-09-01

    Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method and the parity of the states in the sequence has been firmly identified from polarization measurements using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B (E 2) with spin, along with increasing J (2) / B (E 2) values before the band crossing, conclusively establish the origin of these states as arising from antimagnetic rotation. The abrupt increase in the B (E 2) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may possibly indicate the crossing of different shears configurations resulting in the re-opening of a shears structure. The results are reproduced well by numerical calculations within the framework of a semi-classical geometric model.

  11. Precise centering method for triplet of magnetic quadrupole lenses using single rigid frame

    NASA Astrophysics Data System (ADS)

    Lapin, O. S.; Kolinko, S. V.; Rebrov, V. A.; Salivon, V. F.; Ponomarov, Artem; Ponomarev, A. G.

    2017-08-01

    Separated probe-forming systems can be applied to enhance the resolution of a scanning nuclear microprobe with a comparatively large working distance to accommodate the detectors at backward angles. In such systems, magnetic quadrupole lenses are placed at the considerable distance and hence require their precise alignment with the beam axes. Violation of this requirement results in a considerable increasing of a spot size on the target for a constant beam current. Positioning of magnetic quadrupole lenses in a doublet can be implemented in a single-unit design, where a yoke and poles of two lenses are made from one piece of soft iron by precise electrical discharge machining. In a case of triplet, lens manufacturing as a single-unit has technological difficulties. A lens triplet configuration presented in this work comprises placement of three single magnetic quadrupole lenses in a single rigid frame. An approach to lens alignment by the magnetic field reconstruction method was developed and successfully realized.

  12. Development of integrated superconducting quadrupole doublet modules for operation in the SIS100 accelerator

    NASA Astrophysics Data System (ADS)

    Meier, J.; Bleile, A.; Ceballos Velasco, J.; Fischer, E.; Hess, G.; Macavei, J.; Spiller, P.

    2015-12-01

    The FAIR project (Facility for Antiproton and Ion Research) evolves and builds an international accelerator- and experimental facility for basic research activities in various fields of modern physics. Within the course of this project, integrated quadrupole doublet modules are in development. The quadrupole doublet modules provide a pair of superconducting main quadrupoles (focusing and defocusing), corrector magnets, cryogenic collimators and beam position monitors as integrated sets of ion-optical elements. Furthermore LHe cooled beam pipes and vacuum cold-warm transitions are used as ultra-high vacuum components for beam transportation. Superconducting bus bars are used for 13 kA current supply of the main quadrupole magnets. All components are integrated as one common cold mass into one cryostat. High temperature super conductor local current leads will be applied for the low current supply of corrector magnets. The quadrupole doublet modules will be operated in the SIS100 heavy ion accelerator, the core component of the FAIR project. A first version of a corrector magnet has already been manufactured at the Joint Institute for Nuclear Research (JINR), Russia, and is now ready for testing. The ion-optical lattice structure of SIS100 requires multiple configurations of named components. Eleven different configurations, organized in four categories, provide the required quadrupole doublet module setups. The high integration level of multiple ion-optical, mechanical and cryogenic functions, based on requirements of operation safety, is leading towards a sophisticated mechanical structure and cooling solution, to satisfy the demanding requirements on position preservation during thermal cycling. The mechanical and cryogenic design solutions will be discussed.

  13. Simple expressions of the nuclear relaxation rate enhancement due to quadrupole nuclei in slowly tumbling molecules

    SciTech Connect

    Fries, Pascal H.; Belorizky, Elie

    2015-07-28

    For slowly tumbling entities or quasi-rigid lattices, we derive very simple analytical expressions of the quadrupole relaxation enhancement (QRE) of the longitudinal relaxation rate R{sub 1} of nuclear spins I due to their intramolecular magnetic dipolar coupling with quadrupole nuclei of arbitrary spins S ≥ 1. These expressions are obtained by using the adiabatic approximation for evaluating the time evolution operator of the quantum states of the quadrupole nuclei S. They are valid when the gyromagnetic ratio of the spin S is much smaller than that of the spin I. The theory predicts quadrupole resonant peaks in the dispersion curve of R{sub 1} vs magnetic field. The number, positions, relative intensities, Lorentzian shapes, and widths of these peaks are explained in terms of the following properties: the magnitude of the quadrupole Hamiltonian and the asymmetry parameter of the electric field gradient (EFG) acting on the spin S, the S-I inter-spin orientation with respect to the EFG principal axes, the rotational correlation time of the entity carrying the S–I pair, and/or the proper relaxation time of the spin S. The theory is first applied to protein amide protons undergoing dipolar coupling with fast-relaxing quadrupole {sup 14}N nuclei and mediating the QRE to the observed bulk water protons. The theoretical QRE agrees well with its experimental counterpart for various systems such as bovine pancreatic trypsin inhibitor and cartilages. The anomalous behaviour of the relaxation rate of protons in synthetic aluminium silicate imogolite nano-tubes due to the QRE of {sup 27}Al (S = 5/2) nuclei is also explained.

  14. Simple expressions of the nuclear relaxation rate enhancement due to quadrupole nuclei in slowly tumbling molecules

    NASA Astrophysics Data System (ADS)

    Fries, Pascal H.; Belorizky, Elie

    2015-07-01

    For slowly tumbling entities or quasi-rigid lattices, we derive very simple analytical expressions of the quadrupole relaxation enhancement (QRE) of the longitudinal relaxation rate R1 of nuclear spins I due to their intramolecular magnetic dipolar coupling with quadrupole nuclei of arbitrary spins S ≥ 1. These expressions are obtained by using the adiabatic approximation for evaluating the time evolution operator of the quantum states of the quadrupole nuclei S. They are valid when the gyromagnetic ratio of the spin S is much smaller than that of the spin I. The theory predicts quadrupole resonant peaks in the dispersion curve of R1 vs magnetic field. The number, positions, relative intensities, Lorentzian shapes, and widths of these peaks are explained in terms of the following properties: the magnitude of the quadrupole Hamiltonian and the asymmetry parameter of the electric field gradient (EFG) acting on the spin S, the S-I inter-spin orientation with respect to the EFG principal axes, the rotational correlation time of the entity carrying the S-I pair, and/or the proper relaxation time of the spin S. The theory is first applied to protein amide protons undergoing dipolar coupling with fast-relaxing quadrupole 14N nuclei and mediating the QRE to the observed bulk water protons. The theoretical QRE agrees well with its experimental counterpart for various systems such as bovine pancreatic trypsin inhibitor and cartilages. The anomalous behaviour of the relaxation rate of protons in synthetic aluminium silicate imogolite nano-tubes due to the QRE of 27Al (S = 5/2) nuclei is also explained.

  15. Anatoxins and degradation products, determined using hybrid quadrupole time-of-flight and quadrupole ion-trap mass spectrometry: forensic investigations of cyanobacterial neurotoxin poisoning.

    PubMed

    James, Kevin J; Crowley, Janet; Hamilton, Brett; Lehane, Mary; Skulberg, Olav; Furey, Ambrose

    2005-01-01

    The potent neurotoxins from cyanobacteria, anatoxin-a (AN), its methyl analogue, homoanatoxin-a (HMAN), and their degradation products, have been studied using nano-electrospray hybrid quadrupole time-of-flight mass spectrometry (QqTOF-MS). The anatoxin degradation products, which are readily produced in vivo by either reduction or epoxidation, were also examined in this study. The high mass accuracy QqTOF-MS data was used to confirm formula assignments for major product ions and quadrupole ion-trap (QIT)-MS was used to construct fragmentation pathways for anatoxins. Significant differences between these fragmentation pathways were observed. Comparisons between the spectra of compounds that differ in side-chain length (the AN and HMAN series) were used to identify ions that are characteristic of the homologues. The application to forensic samples in which the principal neurotoxin had undergone rapid biodegradation has been demonstrated and used to confirm anatoxin poisoning of dogs. Copyright 2005 John Wiley & Sons, Ltd.

  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. Theory for nanoparticle retention time in the helical channel of quadrupole magnetic field-flow fractionation

    NASA Astrophysics Data System (ADS)

    Williams, P. Stephen; Carpino, Francesca; Zborowski, Maciej

    2009-05-01

    Quadrupole magnetic field-flow fractionation (QMgFFF) is a separation and characterization technique for magnetic nanoparticles such as those used for cell labeling and for targeted drug therapy. A helical separation channel is used to efficiently exploit the quadrupole magnetic field. The fluid and sample components therefore have angular and longitudinal components to their motion in the thin annular space occupied by the helical channel. The retention ratio is defined as the ratio of the times for non-retained and a retained material to pass through the channel. Equations are derived for the respective angular and longitudinal components to retention ratio.

  18. Robust correlations between quadrupole moments of low-lying 2+ states within random-interaction ensembles

    NASA Astrophysics Data System (ADS)

    Lei, Y.

    2016-02-01

    In random-interaction ensembles, three proportional correlations between quadrupole moments of the first two Iπ=2+ states robustly emerge, including Q (21+) =±Q (22+) correlations previously remarked by a realistic nuclear survey, and the Q (22+) =-3/7 Q (21+) correlation, which is only observed in the s d -boson space. These correlations can be microscopically characterized by the rotational SU(3) symmetry and quadrupole vibrational U(5) limit, respectively, according to the Elliott model and the s d -boson mean-field theory. The anharmonic vibration may be another phenomenological interpretation for the Q (21+) =-Q (22+) correlation, whose spectral evidence, however, is insufficient.

  19. Quantum aspects of a moving magnetic quadrupole moment interacting with an electric field

    SciTech Connect

    Fonseca, I. C.; Bakke, K.

    2015-06-15

    The quantum dynamics of a moving particle with a magnetic quadrupole moment that interacts with electric and magnetic fields is introduced. By dealing with the interaction between an electric field and the magnetic quadrupole moment, it is shown that an analogue of the Coulomb potential can be generated and bound state solutions can be obtained. Besides, the influence of the Coulomb-type potential on the harmonic oscillator is investigated, where bound state solutions to both repulsive and attractive Coulomb-type potentials are achieved and the arising of a quantum effect characterized by the dependence of the harmonic oscillator frequency on the quantum numbers of the system is discussed.

  20. Degree of accuracy in determining the nuclear electric quadrupole moment of radium

    SciTech Connect

    Bieron, Jacek; Pyykkoe, Pekka

    2005-03-01

    The multiconfiguration Dirac-Hartree-Fock (MCDHF) model has been employed to calculate the atomic expectation values responsible for the hyperfine splittings of the 7s7p {sup 3}P{sub 1,2} and {sup 1}P{sub 1} levels of radium. Calculated electric field gradients, together with the experimental electric quadrupole hyperfine structure constants, allow us to extract a nuclear electric quadrupole moment Q({sup 223}Ra) of 1.21(0.03) barn. This value is in good agreement with the semiempirical determination based on neutral radium hyperfine and fine structure, but differs from the latest result from an alkali-like radium ion.

  1. Fiducialization of the small-aperture quadrupoles based on the vibrating wire method

    NASA Astrophysics Data System (ADS)

    Wang, Baichuan; Zheng, Shuxin; Wu, Lin; Du, Changtong; Xing, Qingzi; Wang, Zhongming; Qiu, Mengtong; Wang, Xuewu

    2016-03-01

    A fiducialization method based on vibrating wire is described dedicated to the problem of locating the magnetic center relative to external fiducials for the small-aperture quadrupoles. The advantage of this method is that the measurement of the wire position, which may be the main error source, is no longer needed. The position of the magnetic center can be directly obtained by measuring the position shift of the magnet fiducials. This method has been validated on small Permanent Magnet Quadrupoles (PMQs). Experiments have confirmed its feasibility of measuring PMQs with good repeatability of about 10 μm, and shown its high sensitivity as well as convenience.

  2. An effect of nuclear electric quadrupole moments in thermonuclear fusion plasmas

    NASA Technical Reports Server (NTRS)

    De, B. R.; Srnka, L. J.

    1978-01-01

    Consideration of the nuclear electric quadrupole terms in the expression for the fusion Coulomb barrier suggests that this electrostatic barrier may be substantially modified from that calculated under the usual plasma assumption that the nuclei are electric monopoles. This effect is a result of the nonspherical potential shape and the spatial quantization of the nuclear spins of the fully stripped ions in the presence of a magnetic field. For monopole-quadrupole fuel cycles like p-B-11, the fusion cross-section may be substantially increased at low energies if the protons are injected at a small angle relative to the confining magnetic field.

  3. Evaluation of a novel design for an electrostatic quadrupole triplet ion beam lens

    NASA Astrophysics Data System (ADS)

    Burns, L. R.; Bouas, J. D.; Matteson, S.; Weathers, D. L.

    2007-08-01

    We describe the design and evaluation of an electrostatic quadrupole triplet lens constructed to focus ion beams of up to 200 keV in energy. The lens is very compact and incorporates a feature to induce octupole fields that can correct for spherical and other octupole-order aberrations. Two methods were used to evaluate the lens: observation of the focused beam spot on a specially fabricated target while systematically varying lens voltages, and the grid-shadow technique. The latter demonstrated that octupole-order aberrations were completely corrected in one direction when the lens quadrupoles were operated individually and excited to produce an appropriate octupole component of the electric field.

  4. Evaluation of a Novel Design for an Electrostatic Quadrupole Triplet Ion Beam Lens

    NASA Astrophysics Data System (ADS)

    Burns, L. R.; Bouas, J. D.; Matteson, S.; Weathers, D. L.

    2006-10-01

    We describe the design and evaluation of an electrostatic quadrupole triplet lens constructed to focus ion beams of up to 200 keV in energy. The lens is very compact and incorporates a feature to induce octupole fields that can correct for spherical and other octupole-order aberrations. Two methods were used to evaluate the lens: observation of the focused beam spot on a specially fabricated target while systematically varying lens voltages, and the grid-shadow technique. The latter demonstrated that octupole-order aberrations were completely corrected in one direction when the lens quadrupoles were operated individually with appropriate octupole excitations.

  5. Quadrupole splitting and isomer shifts in Te oxides investigated using nuclear forward scattering

    NASA Astrophysics Data System (ADS)

    Klobes, Benedikt; Barrier, Nicolas; Vertruyen, Benedicte; Martin, Christine; Hermann, Raphaël P.

    2014-04-01

    Nuclear forward scattering by 125Te is a viable alternative to conventional 125Te Mössbauer spectroscopy avoiding all source related issues. Using reference compounds with known hyperfine parameters and Te oxides exhibiting stereochemically active lone pairs, we show that nuclear forward scattering by 125Te can be reliably used to extract quadrupole splitting energy and relative isomer shift. The rough correlation between Te-Ocoordination and quadrupole splitting energy as put forward by Takeda and Greenwood (J. Chem. Soc. Dalton, 2207, 1975), is corroborated by the presented results.

  6. An effect of nuclear electric quadrupole moments in thermonuclear fusion plasmas

    NASA Technical Reports Server (NTRS)

    De, B. R.; Srnka, L. J.

    1978-01-01

    Consideration of the nuclear electric quadrupole terms in the expression for the fusion Coulomb barrier suggests that this electrostatic barrier may be substantially modified from that calculated under the usual plasma assumption that the nuclei are electric monopoles. This effect is a result of the nonspherical potential shape and the spatial quantization of the nuclear spins of the fully stripped ions in the presence of a magnetic field. For monopole-quadrupole fuel cycles like p-B-11, the fusion cross-section may be substantially increased at low energies if the protons are injected at a small angle relative to the confining magnetic field.

  7. The nuclear electric quadrupole moment of antimony from the molecular method.

    PubMed

    Haiduke, Roberto L A; da Silva, Albérico B F; Visscher, Lucas

    2006-08-14

    Relativistic Dirac-Coulomb (DC) Hartree-Fock calculations are employed to obtain the analytic electric field gradient (EFG) on the antimony nucleus in the SbN, SbP, SbF, and SbCl molecules. The electronic correlation contribution to the EFGs is included with the DC-CCSD(T) and DC-CCSD-T approaches, also in the four-component framework, using a finite-difference method. The total EFG results, along with the experimental nuclear quadrupole coupling constants from microwave spectroscopy, allow to derive the nuclear quadrupole moments of (121)Sb and (123)Sb, respectively, as -543(11) and -692(14) mb.

  8. Beyond the relativistic mean-field approximation -- collective correlations

    NASA Astrophysics Data System (ADS)

    Li, Zhipan; Nikšić, Tamara; Vretenar, Dario; Yao, Jiangming

    Semi-empirical relativistic energy density functionals (EDFs) or effective interactions implicitly comprise short-range correlations related to the repulsive core of the inter-nucleon interaction, and long-range correlations mediated by nuclear resonance modes. To model spectroscopic properties of finite nuclei, the self-consistent mean-field method must be extended to include collective correlations that arise from restoration of broken symmetries and fluctuations in collective coordinates. These correlations are sensitive to shell effects, vary with particle number, and cannot be included in a universal EDF. We review and compare recent advances in "beyond mean-field" methods based on relativistic EDFs: the angular-momentum and particle-number projected triaxial generator coordinate method, the five-dimensional quadrupole collective Hamiltonian and the axial quadrupole-octupole collective Hamiltonian models. Illustrative applications include low-energy collective excitation spectra and electromagnetic transition rates of nuclei characterised by quadrupole and/or octupole deformations: 24Mg, 76Kr, 240Pu and 224Ra, in comparison with available data.

  9. Excitation Curves of small quadrupoles for tev I Beam Line Use

    SciTech Connect

    Brown, B.

    1985-02-01

    Excitation curves for at least one magnet of each length of TeV I Small Quadrupole have been measured utilizing the MIF-TeV I VAX standard measurement system. Since the standard measurement sequence does not include this sort of excitation curve, the standard reports issued on the magnet does not contain this data. Measurements were taken with the gradient probe SQ25 (probe ID No.40) centered in the aperture and extending through the field length to integrate the strength of the magnet. The parameter BETA2 reported below is the probe calibration factor for this probe in meters**2. The gradient strength of the magnet in Tesla-meters/meter is obtained from the measured flux by dividing by BETA2. The data were collected from MEAS BASE runs in which the measurement probe flux is recorded in a baseline measurement sequence. The hysteresis of the magnet is set by ramping to the specified maximum current then back to zero. The integrator is zeroed at zero current and the integrator voltage recorded one or more times. The current is then ramped successively to the measurement current where the integrator voltage is recorded, to full field and back to zero where the integrator voltage is again recorded for each current at which data is desired. After correction for drift, amplifier gain and integrator Re, the data is recorded in the Reduced data files. This report collects this data for measurements on several magnets. The data at non-zero currents are converted to Tesla and reported also in Tesla/Amp. In order to prepare the report entirely with the DATATRIEVE query language, the usual averaging of Probe Up and Probe Down measurements was not carried out. The reader is invited instead to look at both sets of data to observe that the error to be canceled is small. In addition, this report may not give the best final answers since the final probe calibration may differ from the one used here by a fraction of a per cent. The value used is shown to allow that correction to be

  10. Collection Mapping.

    ERIC Educational Resources Information Center

    Harbour, Denise

    2002-01-01

    Explains collection mapping for library media collections. Discusses purposes for creating collection maps, including helping with selection and weeding decisions, showing how the collection supports the curriculum, and making budget decisions; and methods of data collection, including evaluating a collaboratively taught unit with the classroom…

  11. Collection Mapping.

    ERIC Educational Resources Information Center

    Harbour, Denise

    2002-01-01

    Explains collection mapping for library media collections. Discusses purposes for creating collection maps, including helping with selection and weeding decisions, showing how the collection supports the curriculum, and making budget decisions; and methods of data collection, including evaluating a collaboratively taught unit with the classroom…

  12. Non-Abelian effects in a quadrupole system rotating around two axes

    SciTech Connect

    Zwanziger, J.W.; Koenig, M.; Pines, A. Department of Chemistry, University of California, Berkeley, CA )

    1990-09-01

    The {sup 35}Cl nuclear quadrupole resonance spectrum of a single crystal of sodium chlorate (R. Tycko, Phys. Rev. Lett. 58, 2281 (1987)) rotating about two axes reflects a non-Abelian gauge potential. This gauge potential is an example of Wilczek and Zee's (Phys. Rev. Lett. 52, 2111 (1984)) generalization of Berry's phase to the adiabatic transport of degenerate states.

  13. 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.

  14. A superconducting quadrupole array for transport of multiple high current beams

    SciTech Connect

    Faltens, A.; Shuman, D.

    1999-11-01

    We present a conceptual design of a superconducting quadrupole magnet array for the side-by-side transport of multiple high current particle beams in induction linear accelerators. The magnetic design uses a modified cosine 20 current distribution inside a square cell boundary. Each interior magnet's neighbors serve as the return flux paths and the poles are placed as close as possible to each other to facilitate this. No iron is present in the basic 2-D magnetic design; it will work at any current level without correction windings. Special 1/8th quadrupoles are used along the transverse periphery of the array to contain and channel flux back into the array, making every channel look as part of an infinite array. This design provides a fixed dimension array boundary equal to the quadrupole radius that can be used for arrays of any number of quadrupole channels, at any field level. More importantly, the design provides magnetic field separation between the array and the induction cores which may be surrounding it. Flux linkage between these two components can seriously affect the operation of both of them.

  15. THE FORTUITOUS LATITUDE OF THE PIERRE AUGER OBSERVATORY AND TELESCOPE ARRAY FOR RECONSTRUCTING THE QUADRUPOLE MOMENT

    SciTech Connect

    Denton, Peter B.; Weiler, Thomas J. E-mail: tom.weiler@vanderbilt.edu

    2015-03-20

    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.

  16. Beam dynamics and stability analysis of an intense beam in a continuously twisted quadrupole focusing channel

    NASA Astrophysics Data System (ADS)

    Goswami, A.; Sing Babu, P.; Pandit, V. S.

    2016-11-01

    This paper describes the dynamics of a space-charge-dominated beam through a continuously twisted quadrupole magnet using ten independent first-order differential equations of the beam matrix elements under the assumption of linear space-charge force. Various beam optical properties of the magnet and the evolution of the emittance that results from the coupling between the two transverse planes are studied. The perturbed equations of motion around the matched beam envelopes have been derived and utilized to analyze the stability properties of the intense beam transport by calculating the eigenvalues of the transfer map over one lattice period. Detailed analysis shows the presence of instability due to parametric resonances in a twisted quadrupole channel which generally does not appear in the FODO quadrupole channel. A 2D particle-in-cell simulation code has been developed and utilized to verify the analytical results and to examine the behavior of the intense beam with Gaussian (GA) distribution in the twisted quadrupole channel.

  17. Correlation between y-Type Ions Observed in Ion Trap and Triple Quadrupole Mass Spectrometers

    PubMed Central

    Sherwood, Carly A.; Eastham, Ashley; Lee, Lik Wee; Risler, Jenni; Vitek, Olga; Martin, Daniel B.

    2009-01-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a technique for high-sensitivity targeted analysis. In proteomics, MRM-MS can be used to monitor and quantify a peptide based on the production of expected fragment peaks from the selected peptide precursor ion. The choice of which fragment ions to monitor in order to achieve maximum sensitivity in MRM-MS can potentially be guided by existing MS/MS spectra. However, because the majority of discovery experiments are performed on ion trap platforms, there is concern in the field regarding the generalizability of these spectra to MRM-MS on a triple quadrupole instrument. In light of this concern, many operators perform an optimization step to determine the most intense fragments for a target peptide on a triple quadrupole mass spectrometer. We have addressed this issue by targeting, on a triple quadrupole, the top six y-ion peaks from ion trap-derived consensus library spectra for 258 doubly charged peptides from three different sample sets and quantifying the observed elution curves. This analysis revealed a strong correlation between the y-ion peak rank order and relative intensity across platforms. This suggests that y-type ions obtained from ion trap-based library spectra are well-suited for generating MRM-MS assays for triple quadrupoles and that optimization is not required for each target peptide. PMID:19603825

  18. Electron Cloud Generation and Trapping in a Quadrupole Magnet at the Los Alamos Proton Storage Ring

    SciTech Connect

    Macek, Robert J.; Browman, Andrew A.; Ledford, John E.; Borden, Michael J.; O'Hara, James F.; McCrady, Rodney C.; Rybarcyk, Lawrence J.; Spickermann, Thomas; Zaugg, Thomas J.; Pivi, Mauro T.F.; /SLAC

    2008-03-17

    Recent beam physics studies on the two-stream e-p instability at the LANL proton storage ring (PSR) have focused on the role of the electron cloud generated in quadrupole magnets where primary electrons, which seed beam-induced multipacting, are expected to be largest due to grazing angle losses from the beam halo. A new diagnostic to measure electron cloud formation and trapping in a quadrupole magnet has been developed, installed, and successfully tested at PSR. Beam studies using this diagnostic show that the 'prompt' electron flux striking the wall in a quadrupole is comparable to the prompt signal in the adjacent drift space. In addition, the 'swept' electron signal, obtained using the sweeping feature of the diagnostic after the beam was extracted from the ring, was larger than expected and decayed slowly with an exponential time constant of 50 to 100 {micro}s. Other measurements include the cumulative energy spectra of prompt electrons and the variation of both prompt and swept electron signals with beam intensity. Experimental results were also obtained which suggest that a good fraction of the electrons observed in the adjacent drift space for the typical beam conditions in the 2006 run cycle were seeded by electrons ejected from the quadrupole.

  19. 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.

  20. The use of stability bands to improve the performance of quadrupole mass filters

    NASA Astrophysics Data System (ADS)

    Sudakov, M. Yu.; Mamontov, E. V.

    2017-01-01

    The possibility of increasing the resolving power of quadrupole mass filters has been discussed. It has been shown that the limitations associated with the finite time of flight imposed by Von Zahn's rule are modified while using the islands of stability that appear when quadrupole is excited by the additional signals. By calculation of the exponential increment of growth of the oscillation amplitude the effect of the acceleration of mass separation and improvement of the peak shape, when the islands of stability are used for ion filtering, is explained. The case of the excitation by two signals at different frequencies has been studied theoretically. The conditions under which suppression of the first order resonance for one of the directions of motion is obtained. The direct modeling of the peak shape of the mass filter shows the possibility of obtaining a resolution of 10,000 with a time of flight of ions through the quadrupole of 100 cycles of the main RF supply, and low sensitivity of the new operating mode to the nonlinear field distortions in the quadrupoles with rods of circular cross sections.

  1. 57Fe quadrupole splitting and isomer shift in various oxyhemoglobins: study using Mössbauer spectroscopy

    NASA Astrophysics Data System (ADS)

    Oshtrakh, M. I.; Berkovsky, A. L.; Kumar, A.; Kundu, S.; Vinogradov, A. V.; Konstantinova, T. S.; Semionkin, V. A.

    2010-04-01

    A comparative study of normal human, rabbit and pig oxyhemoglobins and oxyhemoglobin from patients with chronic myeloleukemia and multiple myeloma using Mössbauer spectroscopy with a high velocity resolution demonstrated small variations of the 57Fe quadrupole splitting and isomer shift. These variations may be a result of small structural differences in the heme iron stereochemistry of various hemoglobins.

  2. Joint and angle-covariant spin measurements with a quadrupole magnetic field

    NASA Technical Reports Server (NTRS)

    Martens, Hans; Demuynck, Willem M.

    1994-01-01

    We study a Stern-Gerlach type setup, with a quadrupole magnetic field, for neutral particles of arbitrary spin. The Hamiltonian is of a form proposed for joint measurements of the incompatible observables. The measurement results are discussed, showing the limitation of such Hamiltonians. Some remarks are made on the relevance of covariance as a criterion for measurement schemes.

  3. 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.

  4. 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.

  5. Correlation between y-type ions observed in ion trap and triple quadrupole mass spectrometers.

    PubMed

    Sherwood, Carly A; Eastham, Ashley; Lee, Lik Wee; Risler, Jenni; Vitek, Olga; Martin, Daniel B

    2009-09-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a technique for high-sensitivity targeted analysis. In proteomics, MRM-MS can be used to monitor and quantify a peptide based on the production of expected fragment peaks from the selected peptide precursor ion. The choice of which fragment ions to monitor in order to achieve maximum sensitivity in MRM-MS can potentially be guided by existing MS/MS spectra. However, because the majority of discovery experiments are performed on ion trap platforms, there is concern in the field regarding the generalizability of these spectra to MRM-MS on a triple quadrupole instrument. In light of this concern, many operators perform an optimization step to determine the most intense fragments for a target peptide on a triple quadrupole mass spectrometer. We have addressed this issue by targeting, on a triple quadrupole, the top six y-ion peaks from ion trap-derived consensus library spectra for 258 doubly charged peptides from three different sample sets and quantifying the observed elution curves. This analysis revealed a strong correlation between the y-ion peak rank order and relative intensity across platforms. This suggests that y-type ions obtained from ion trap-based library spectra are well-suited for generating MRM-MS assays for triple quadrupoles and that optimization is not required for each target peptide.

  6. Accurate measurements of electric quadrupole hyperfine interactions of very dilute spins in magnetic solids

    NASA Astrophysics Data System (ADS)

    Chaplin, D. H.; Hutchison, W. D.; Prandolini, M. J.; Bowden, G. J.

    1998-01-01

    The application of double and triple resonance techniques to enhance signals in quadrupole interaction — nuclear magnetic resonance on oriented nuclei spectroscopy, is illustrated for the antiferromagnet ( 54Mn)MnBr 2-4H 2O. Unusual shifts of the quadrupolar split, higher order, ν ±2, ±1 subresonance, comparable to the NMRON linewidth, are observed and explained.

  7. 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( θ) 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 θ( θ) along the magnet. The field quality appears satisfactory for the short transport experiments through these quadrupoles.

  8. Electric quadrupole moment of the proton halo nucleus {sup 8}B

    SciTech Connect

    Sumikama, T.; Nagatomo, T.; Ogura, M.; Iwakoshi, T.; Nakashima, Y.; Fujiwara, H.; Matsuta, K.; Fukuda, M.; Mihara, M.; Minamisono, T.

    2006-08-15

    The {beta}-NQR (nuclear quadrupole resonance) signals of {sup 8}B (I{sup {pi}}=2{sup +},T{sub 1/2}=770 ms) implanted in TiO{sub 2} (rutile) have been detected to determine the electric quadrupole moment of {sup 8}B with high precision. The ratio of the quadrupole moments of {sup 8}B and {sup 12}B was determined as |Q({sup 8}B)/Q({sup 12}B)|=4.88{+-}0.04. Combined with the known sign, the quadrupole moment of {sup 8}B was obtained as Q({sup 8}B)=+(64.5{+-}1.4) mb, which is consistent with and more precise than the previously reported value. The experimental values of the Q moment, the proton and neutron radii and the density distribution of {sup 8}B were compared with several theoretical predictions and were found to be best reproduced by a microscopic cluster model, which suggests the existence of a proton halo.

  9. Correlation of experimental data and three-dimensional finite element modeling of a spinning quadrupole

    NASA Astrophysics Data System (ADS)

    Lorimer, W. L.; Lieu, D. K.; Hull, J. R.; Mulcahy, T. M.; Rossing, T. D.

    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.

  10. Classical Monte Carlo Study for Antiferro Quadrupole Orders in a Diamond Lattice

    NASA Astrophysics Data System (ADS)

    Hattori, Kazumasa; Tsunetsugu, Hirokazu

    2016-09-01

    We investigate antiferro quadrupole orders in a diamond lattice under magnetic fields by Monte Carlo simulations for two types of classical effective models. One is an XY model with Z3 anisotropy, and the other is a two-component ϕ4 model with a third-order anisotropy. We confirm that the universality class of the zero-field transition is that for the three-dimensional XY model. Magnetic field corresponds to a Z3 field in the effective model, and under this field, we find that collinear and canted antiferro-quadrupole orders compete. Each phase is characterized by symmetry breaking in the sector of (sublattice Z2) otimes (reflection Z2 for the order parameter). When Z3 anisotropy and magnetic field vary, it turns out that this system is a good playground for various multicritical points; bicritical and tetracritical points emerge in a finite field. Another important finding is about the scaling of parasitic ferro quadrupole order at the zero-field critical point. This is the secondary order parameter induced by the primary antiferro order, and its critical exponent β' = 0.815 clearly differs from the expected value that is twice the value for the primary order parameter. The corresponding correlation length exponent is also different, ν' = 0.597(12). We also discuss relation of the present effective quadrupole models with the 3-state Potts model as well as implication to understanding of orbital orders in Pr-based 1-2-20 compounds.

  11. The importance of quadrupole sources in prediction of transonic tip speed propeller noise

    NASA Technical Reports Server (NTRS)

    Hanson, D. B.; Fink, M. R.

    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 in the direction blade motion. These sources are compared in both the time domain and the frequency domain using two dimensional airfoil theories valid in the subsonic, transonic, and supersonic speed ranges. For nonlifting parabolic arc blades, the two sources are equally important at speeds between the section critical Mach number and a Mach number of one. However, for moderately subsonic or fully supersonic flow over thin blade sections, the quadrupole term is negligible. It is concluded for thin blades that significant quadrupole noise radiation is strictly a transonic phenomenon and that it can be suppressed with blade sweep. Noise calculations are presented for two rotors, one simulating a helicopter main rotor and the other a model propeller. For the latter, agreement with test data was substantially improved by including the quadrupole source term.

  12. Quadrupole mass spectrometer for a mobile laboratory to measure isotope ratios

    SciTech Connect

    Walton, J.R.; Smith, D.H.; McKown, H.S.; Carter, J.A.

    1981-01-01

    A mobile laboratory has been assembled for on-site inspection of plant operations handlng special nuclear materials. The isotopic composition of U, Pu, and other elements can be analyzed using a quadrupole mass spectrometer. Some results of analysis of uranium and boron standards are given. (DLC)

  13. LARP Long Quadrupole: A "Long" Step Toward an LHC Luminosity Upgrade with Nb3Sn Magnets

    SciTech Connect

    Ambrosio, Giorgio

    2008-02-13

    The beginning of the development of Nb3Sn magnets for particle accelerators goes back to the 1960's. But only very recently has this development begun to face the challenges of fabricating Nb3Sn magnets which can meet the requirements of modern particle accelerators. LARP (the LHC Accelerator Research Program) is leading this effort focusing on long models of the Interaction Region quadrupoles for a possible luminosity upgrade of the Large Hadron Collider. A major milestone in this development is to test, by the end of 2009, 4m-long quadrupole models, which will be the first Nb3Sn accelerator-type magnets approaching the length of real accelerator magnets. The Long Quadrupoles (LQ) are 'Proof-of-Principle' magnets which are to demonstrate that Nb3Sn technology is sufficiently mature for use in high energy particle accelerators. Their design is based on the LARP Technological Quadrupole (TQ) models, under development at FNAL and LBNL, which have design gradients higher than 200 T/m and an aperture of 90 mm. Several challenges must be addressed for the successful fabrication of long Nb3Sn coils and magnets. These challenges and the solutions adopted will be presented together with the main features of the LQ magnets. Several R&D lines are participating to this effort and their contributions will be also presented.

  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

  15. Inductively coupled plasma mass spectrometer with axial field in a quadrupole reaction cell.

    PubMed

    Bandura, Dmitry R; Baranov, Vladimir I; Tanner, Scott D

    2002-10-01

    A novel reaction cell for ICP-MS with an electric field provided inside the quadrupole along its axis is described. The field is implemented via a DC bias applied to additional auxiliary electrodes inserted between the rods of the quadrupole. The field reduces the settling time of the pressurized quadrupole when its mass bandpass is dynamically tuned. It also improves the transmission of analyte ions. It is shown that for the pressurized cell with the field activated, the recovery time for a change in quadrupole operating parameters is reduced to <4 ms, which allows fast tuning of the mass bandpass in concert with and at the speed of the analyzing quadrupole. When the cell is operated with ammonia, the field reduces ion-ammonia cluster formation, further enhancing the transmission of atomic ions that have a high cluster formation rate. Ni x (NH3)n+ cluster formation in a cell operated with a wide bandpass (i.e., Ni+ precursors are stable in the cell) is shown to be dependent on the axial field strength. Clusters at n = 2-4 can be suppressed by 9, 1200, and >610 times, respectively. The use of a retarding axial field for in-situ energy discrimination against cluster and polyatomic ions is shown. When the cell is pressurized with O2 for suppression of 129Xe+, the formation of 127IH2+ by reactions with gas impurities limits the detection of 129I to isotopic abundance of approximately 10(-6). In-cell energy discrimination against 127IH2+ utilizing a retarding axial field is shown to reduce the abundance of the background at m/z = 129 to ca. 3 x 10(-8) of the 127I+ signal. In-cell energy discrimination against 127IH2+ is shown to cause less I+ loss than a post-cell potential energy barrier for the same degree of 127IH2+ suppression.

  16. The electric quadrupole moment of molecular hydrogen ions and their potential for a molecular ion clock

    NASA Astrophysics Data System (ADS)

    Bakalov, D.; Schiller, S.

    2014-01-01

    The systematic shifts of the transition frequencies in the molecular hydrogen ions are of relevance to ultra-high-resolution radio-frequency, microwave and optical spectroscopy of these systems, performed in ion traps. We develop the ab initio description of the interaction of the electric quadrupole moment of this class of molecules with the static electric field gradients present in ion traps. In good approximation, it is described in terms of an effective perturbation Hamiltonian. An approximate treatment is then performed in the Born-Oppenheimer approximation. We give an expression of the electric quadrupole coupling parameter valid for all hydrogen molecular ion species and evaluate it for a large number of states of H{2/+}, HD+, and D{2/+}. The systematic shifts can be evaluated as simple expectation values of the perturbation Hamiltonian. Results on radio-frequency, one-photon electric dipole (E1), and two-photon E1 transitions between hyperfine states in HD+ are reported. For two-photon E1 transitions between rotationless states, the shifts vanish. For a large subset of rovibrational one-photon transitions, the absolute values of the quadrupole shifts range from 0.3 to 10 Hz for an electric field gradient of 108 V/m2. We point out an experimental procedure for determining the quadrupole shift which will allow reducing its contribution to the uncertainty of unperturbed rovibrational transition frequencies to the 1 × 10-15 fractional level and, for selected transitions, even below it. The combined contributions of black-body radiation, Zeeman, Stark and quadrupole effects are considered for a large set of transitions, and it is estimated that the total transition frequency uncertainty of selected transitions can be reduced below the 1 × 10-15 level.

  17. Global Correlations for Low-Lying Collective 2+ States

    NASA Astrophysics Data System (ADS)

    Qin, Z. Z.; Lei, Y.; Pittel, S.; Bijker, R.

    2017-07-01

    By using the triaxial rotor model and the anharmonic vibrator model with phonon mixing, we derive a global correlation between the quadrupole moments of the two lowest 2+ states in collective nuclei that had previously been observed in experimental data across the periodic table. We then derive other electromagnetic properties for these two models of nuclear structure and compare them globally with experimental data. We find that both models are able to robustly describe the experimental data across the region of nuclei for which the models are applicable, including a large number that they have in common. We then show that there seems to exists a robust orthogonal transformation between these two models for realistic nuclear systems, suggesting that these two seemingly diverse descriptions of quadrupole collective phenomena seem to act in a similar model space and may therefore have a common origin.

  18. Large-scale shell model calculations for odd-odd nuclei and comparison to experimental studies of fission product nuclei in the /sup 132/Sn region

    SciTech Connect

    Lane, S.M.; Henry, E.A.; Meyer, R.A.

    1985-01-08

    Experimental spectroscopy data of fission products have been obtained using highly automated and rapid chemical separations followed by automated spectroscopy studies of isolated fission products. These data have established the presence of only a single level with spin-parity of 1/sup +/ below 1500 keV of excitation in Z = 51 /sup 132/Sb/sub 81/. This is in contrast to the results of our studies of /sup 130/Sb and /sup 134/I. For /sup 134/I, the N = 81 isotone with Z = 53, we can characterize three 1/sup +/ levels below 1200 keV. For /sup 130/Sb/sub 79/ that has a neutron pair less than /sup 132/Sb, we can identify two 1/sup +/ levels below 1100 keV. We can account for the additional levels using the LLNL shell-model code which is based on the Lanczos tridiagonalization algorithm using an uncoupled m-scheme basis and vector manipulations. The 1g/sub 7/2/, 2d/sub 5/2/, 2d/sub 3/2/, 1h/sub 11/2/, and 3s/sub 1/2/ orbitals are available to the valence protons and the 2d/sub 5/2/, 2d/sub 3/2/, 1h/sub 11/2/, and 3s/sub 1/2/ orbitals are available to the valence neutron holes. Analysis of the wavefunctions show the dominant role of three nucleon cluster configurations in producing the increased number of states at low energy. The absence of nucleon cluster configurations in the parent nucleus /sup 130/Sn is used to explain the reduction of approximately a factor of 20 in the Gamow-Teller beta strength to the low lying 1/sup +/ levels of /sup 130/Sb. 27 references.

  19. Magnetic dipole moments near 132Sn: Measurement on isomeric {11}/{2 -} states in odd- A131Te and 133Te by NMR/ON

    NASA Astrophysics Data System (ADS)

    White, G.; Rikovska, J.; Stone, N. J.; Copnell, J.; Towner, I. S.; Oros, A. M.; Heyde, K.; Fogelberg, B.; Jacobsson, L.; Gustavsson, F.

    1998-09-01

    On-line low temperature nuclear orientation (OLNO) experiments have been performed on the odd- A Te isotopes 131Te and 133Te using the technique of nuclear magnetic resonance on oriented nuclei (NMR/ON). The magnetic moments of the isomeric {11}/{2 -} states have been measured extending the known data on these states in the Te isotopes up to the neutron shell closure at N = 82. The contribution to the {11}/{2 -} magnetic moment in 133Te due to core polarisation is calculated using an RPA shell model as well as corrections to the magnetic dipole operator caused by mesonic exchange currents. The neutron number dependence of the magnetic moments of the {11}/{2 -} isomers in heavy Te isotopes is discussed in terms of particle-core coupling model (PCM) calculations.

  20. Triaxial quadrupole dynamics and the inner fission barrier of some heavy even-even nuclei

    NASA Astrophysics Data System (ADS)

    Benrabia, K.; Medjadi, D. E.; Imadalou, M.; Quentin, P.

    2017-09-01

    Background: Inner fission barriers of actinide nuclei have been known for a long time to be unstable with respect to the axial symmetry. On the other hand, taking into account the effect of the relevant adiabatic mass parameter reduces or even may wash out this instability. A proper treatment of the dynamics for both axial and triaxial modes is thus crucial to accurately determine the corresponding fission barriers. This entails in particular an accurate description of pairing correlations. Purpose: We evaluate the potential energies, moments of inertia, and vibrational mass parameters in a two-dimensional relevant deformation space (corresponding to the usual β and γ quadrupole deformation parameters) for four actinide nuclei (236U, 240Pu, 248Cm, and 252Cf). We assess the relevance of our approach to describe the dynamics for a triaxial mode by computing the low energy spectra (exploring thus mainly the equilibrium deformation region). We evaluate the inner fission barrier heights releasing the axial symmetry constraint. Method: Calculations within the Hartree-Fock plus BCS approach are performed using the SkM* Skyrme effective interaction in the particle-hole channel and a seniority force in the particle-particle channel. The intensity of this residual interaction has been fixed to allow a good reproduction of some odd-even mass differences in the actinide region. Adiabatic mass parameters for the rotational and vibrational modes are calculated using the Inglis-Belyaev formula supplemented by a global renormalization factor taking into account the so-called Thouless-Valatin corrections. Spectra are obtained through the diagonalization of the corresponding Bohr collective Hamiltonian. Results: The experimental low energy spectra are qualitatively well reproduced by our calculations for the considered nuclei. Inner fission barrier heights are calculated and compared with available estimates from various experimental data. The reproduction of the data is better

  1. Quadrupole Strong Focusing for Transport of Space-Charge Dominated Electron Beams in Traveling-Wave Tubes

    NASA Astrophysics Data System (ADS)

    Nichols, Kimberley E. L.

    Analysis of quadrupole focusing lattices for high-frequency TWT's is presented. This work is motivated by recent work performed at the Naval Research Laboratory (NRL) which demonstrated an advantageous case for strong focusing employing a Halbach quadrupole lattice. Using realistic Permanent Magnet Quadruple (PMQ) field cancellation, the advantage of using PMQ to transport higher current densities than Permanent Periodic Magnet (PPM) lattices disappears, while other advantages for employing quadrupole focusing remain. This dissertation gives a comprehensive analysis of the applicability of PMQ focusing in vacuum electronic devices.

  2. Static quadrupole moment of high-spin isomers in the doubly-odd {sup 214}Fr nucleus

    SciTech Connect

    Neyens, G.; Van Asbroeck, I.; Coussement, R.

    1995-06-01

    We have determined the spectroscopic quadrupole moment of two high-spin isomers ({ital I}=11 {h_bar} and {ital I}=32 {h_bar}) which have recently been identified in the doubly-odd {sup 214}Fr nucleus. The data have been extracted from a series of former level mixing spectroscopy (LEMS) measurements which had been performed to measure quadrupole moments of high-spin isomers in {sup 211,212,213}Fr isotopes. The quadrupole frequencies were measured in natural and enriched poly- and single-crystalline T1 at different temperatures.

  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

  4. Collecting apparatus

    DOEpatents

    Duncan, Charles P.

    1983-01-01

    An improved collecting apparatus for small aquatic or airborne organisms such as plankton, larval fish, insects, etc. The improvement constitutes an apertured removal container within which is retained a collecting bag, and which is secured at the apex of a conical collecting net. Such collectors are towed behind a vessel or vehicle with the open end of the conical net facing forward for trapping the aquatic or airborne organisms within the collecting bag, while allowing the water or air to pass through the apertures in the container. The container is readily removable from the collecting net whereby the collecting bag can be quickly removed and replaced for further sample collection. The collecting bag is provided with means for preventing the bag from being pulled into the container by the water or air flowing therethrough.

  5. Factors determining the performance of triple quadrupole, quadrupole ion trap and sector field mass spectrometer in electrospray ionization mass spectrometry. 2. Suitability for de novo sequencing.

    PubMed

    Premstaller, A; Huber, C G

    2001-01-01

    The sequence coverage by fragment ions resulting from collision-induced dissociation in a triple stage quadrupole (TSQ) and a quadrupole ion trap (QIT) mass spectrometer of 10-20-mer oligonucleotides was investigated. While (a-B) and w ion series were the most abundant on both instruments, additional ion series of sequence relevance were preferably formed in the TSQ. Thus, a total number of 83 fragment ions were used to deduce the complete sequence of a 10-mer oligonucleotide of mixed sequence from a tandem mass spectrum recorded on the TSQ. The complete sequence was also encoded in the 28 fragments that were obtained from the QIT under comparable fragmentation conditions. Spectrum complexity increased considerably at the cost of signal-to-noise ratio upon fragmentation of a 20-mer oligonucleotide in the TSQ, whereas spectrum interpretation with longer oligonucleotides was significantly more straightforward in spectra recorded on the QIT. The extent of fragmentation had to be optimized by appropriate setting of collision energy and choice of precursor ion charge state in order to obtain full sequence coverage by fragments for de novo sequencing. Moreover, full sequence information was also dependent on base sequence because of the low tendency of backbone cleavage at thymidines. Tandem mass spectrometry on the QIT yielded redundant information that was successfully utilized to deduce the complete sequence of 20-mer oligonucleotides with high confidence. Copyright 2001 John Wiley & Sons, Ltd.

  6. 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.

    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.

  7. Phenolic profiling of the skin, pulp and seeds of Albariño grapes using hybrid quadrupole time-of-flight and triple-quadrupole mass spectrometry.

    PubMed

    Di Lecce, Giuseppe; Arranz, Sara; Jáuregui, Olga; Tresserra-Rimbau, Anna; Quifer-Rada, Paola; Lamuela-Raventós, Rosa M

    2014-02-15

    This paper describes for the first time a complete characterisation of the phenolic compounds in different anatomical parts of the Albariño grape. The application of high-performance liquid chromatography coupled with two complementary techniques, hybrid quadrupole time-of-flight and triple-quadrupole mass spectrometry, allowed the phenolic composition of the Albariño grape to be unambiguously identified and quantified. A more complete phenolic profile was obtained by product ion and precursor ion scans, while a neutral loss scan at 152 u enabled a fast screening of procyanidin dimers, trimers and their galloylated derivatives. The compounds were confirmed by accurate mass measurements in QqToF-MS and QqToF-MS/MS modes at high resolution, and good fits were obtained for all investigated ions, with errors ranging from 0.2 to 4.5 mDa. To the best of our knowledge, two flavanol monomer hexosides were detected in the grape berry for the first time.

  8. Liquid chromatography with triple-quadrupole or quadrupole-time of flight mass spectrometry for screening and confirmation of residues of pharmaceuticals in water.

    PubMed

    Stolker, Alida A M; Niesing, Willem; Hogendoorn, Elbert A; Versteegh, Johanna F M; Fuchs, Regine; Brinkman, Udo A Th

    2004-02-01

    LC-MS-MS has been performed with triple-quadrupole (QqQ) and quadrupole-time of flight (Q-ToF) instruments and has been used for screening and confirmation of pharmaceuticals in surface, drinking, and ground water. Screening was based on monitoring of one specific MS-MS ion of the target compounds. Confirmation of the identity of the pharmaceuticals was based either on the monitoring of two specific MS-MS ions and calculation of the ratio of their intensities, or on the exact masses of MS-MS product ions obtained for a molecular ion by use of LC-Q-ToF MS. The set of pharmaceuticals included four analgesics (acetylsalicylic acid, diclofenac, ibuprofen, and paracetamol), three antibiotics (sulfamethoxazole, erythromycin, and chloramphenicol), five blood-lipid regulators and beta-blockers (fenofibrate, bezafibrate, clofibric acid, bisoprolol, and metoprolol), and the anti-epileptic drug carbamazepine. Limits of quantification ranged from 5 to 25 ng L(-1). Fifty-six samples were analysed and residues of the pharmaceuticals were detected in almost all surface and groundwater and in some drinking water samples. The identity of the compounds could be confirmed by use of both QqQ- and Q-ToF-based LC-MS-MS. However, the latter technique has the distinct advantage that a large number of pharmaceuticals can be screened and confirmed at low concentrations (1-100 ng L(-1)) in one run.

  9. Test of a NbTi Superconducting Quadrupole Magnet Based on Alternating Helical Windings

    SciTech Connect

    Caspi, S.; Trillaud, F.; Godeke, A.; Dietderich, D.; Ferracin, P.; Sabbi, G.; Giloux, C.; Perez, J. G.; Karppinen, M.

    2009-08-16

    It has been shown that by superposing two solenoid-like thin windings, that are oppositely skewed (tilted) with respect to the bore axis, the combined current density on the surface is cos({theta})-like and the resulting magnetic field in the bore is a pure dipole field. Following a previous test of such a superconducting dipole magnet, a quadrupole magnet was designed and built using similar principles. This paper describes the design, construction and test of a 75 mm bore 600 mm long superconducting quadrupole made with NbTi wire. The simplicity of the design, void of typical wedges, end-spacers and coil assembly, is especially suitable for future high field insert coils using Nb{sub 3}Sn as well as HTS wires. The 3 mm thick coil reached 46 T/m but did not achieve its current plateau.

  10. Two-color photoexcitation of Rydberg states via an electric quadrupole transition

    SciTech Connect

    Li Leping; Gu Quanli; Knee, J. L.; Wright, J. D.; DiSciacca, J. M.; Morgan, T. J.

    2008-03-15

    We report the observation of an electric quadrupole transition between the 4s{sup '}[1/2]{sub 0}{sup o} and 3d[3/2]{sub 2}{sup o} states in the spectrum of argon and use it in the first step of a scheme to excite Rydberg states. The initial identification of the transition is based on one-color, two-photon photoionization. A different experiment utilizing two-color, two-photon photoexcitation to Rydberg states confirms the identification. Despite the unavoidable background of one-color, two-photon photoionization, the latter experimental technique makes possible two-photon spectroscopy of Rydberg states using a resonant intermediate state populated by an electric quadrupole transition.

  11. Quadrupole lattice resonances in plasmonic crystal excited by cylindrical vector beams

    PubMed Central

    Sakai, Kyosuke; Nomura, Kensuke; Yamamoto, Takeaki; Omura, Tatsuya; Sasaki, Keiji

    2016-01-01

    We report a scheme to exploit low radiative loss plasmonic resonance by combining a dark (subradiant) mode and a lattice resonance. We theoretically demonstrate that such dark-mode lattice resonances in periodic arrays of nanodisks or plasmonic crystals can be excited by vertically incident light beams. We investigate the excitation of lattice resonances in a finite sized, square-lattice plasmonic crystal by two types of cylindrical vector beams and a linearly polarized Gaussian beam. Quadrupole lattice resonances are excited by all three beams, and the largest peak intensity is obtained by using a specific type of cylindrical vector beam. Because of their lower radiative losses with many hotspots, the quadrupole lattice resonances in plasmonic crystal may pave the way for photonic research and applications that require strong light-matter interactions. PMID:27734923

  12. Charge and quadrupole fluctuations and gap anisotropy in BiS2-based superconductors

    NASA Astrophysics Data System (ADS)

    Suzuki, Katsuhiro; Usui, Hidetomo; Kuroki, Kazuhiko; Ikeda, Hiroaki

    2017-07-01

    Recent angle-resolved spectroscopy in BiS2-based superconductors has indicated that the superconducting gap amplitude possesses remarkable anisotropy and/or a sign change on a small Fermi pocket around the X point. It implies a possibility of an unconventional pairing state. Here we study the gap anisotropy in superconductivity mediated by inherent charge and quadrupole fluctuations in an extended Hubbard model, which includes intersite interaction between Bi and S atoms. The first-principles downfolded band structure is composed of Bi 6 px/py and S 3 px/py orbitals on a BiS2 single layer. Evaluating the linearized gap equation, we find that the ferroic charge and quadrupole fluctuation driven by the intersite interaction leads to a fully gapped dx2-y2-wave pairing state, in which the gap amplitude has sizable anisotropy on the Fermi surface.

  13. Interplay between the pairing and quadrupole interactions in the algebraic realization of the microscopic shell model

    NASA Astrophysics Data System (ADS)

    Drumev, Kalin; Georgieva, Ana

    2015-04-01

    We explore the algebraic realization of the Pairing-Plus-Quadrupole Model/PQM/ in the framework of the Elliott‘s SU(3) Model with the aim to obtain the complementary and competing features of the two interactions through the relation between the pairing and the SU(3) bases. First, we establish a correspondence between the SO(8) pairing basis and the Elliott's SU(3) basis. It is derived from their complementarity to the same LST coupling chain of the shell-model number-conserving algebra. The probability distribution of the SU(3) basis states within the SO(8) pairing states is also obtained and allows the investigation of the interplay between the pairing and quadrupole interactions in the Hamiltonian of the PQM, containing both of them as limiting cases. The description of some realistic N∼Z nuclear systems is investigated in a SU(3)-symmetry-adapted basis within a model space of one and two oscillator shells.

  14. NMR Observation of Ferro-Quadrupole Order in PrTi2Al20

    NASA Astrophysics Data System (ADS)

    Taniguchi, Takanori; Yoshida, Makoto; Takeda, Hikaru; Takigawa, Masashi; Tsujimoto, Masaki; Sakai, Akito; Matsumoto, Yosuke; Nakatsuji, Satoru

    2016-11-01

    We report the results of 27Al-NMR measurements on a single crystal of PrTi2Al20. This compound shows a phase transition near 2 K associated with the quadrupole degree of freedom of Pr ions, for which the ground state of the crystalline electric field is a nonmagnetic doublet. When a magnetic field is applied along the <111> direction, the NMR lines split upon entering the low-temperature phase, indicating the breaking of the three fold rotation symmetry due to the field-induced magnetic dipole perpendicular to the field. This provides microscopic evidence for a ferro order of the O20 quadrupole. Although a first-order transition is expected theoretically, the line splitting evolves continuously within the experimental resolution.

  15. Fabrication and Test of LARP Technological Quadrupole Models of TQC Series

    SciTech Connect

    Bossert, Rodger C.; Ambrosio, Giorgio; Andreev, Nilolai; Barzi, Emanuela; Chlachidze, Guram; Feher, Sandor; Kashikhin, Vladimir S.; Kashikhin, Vadim V.; Lamm, Michael; Nobrega, Alfred; Novitski, Igor; Orris, Darryl; Tartaglia, Michael; Zlobin, Alexander V.; Caspi, Shlomo; Dietderich, Daniel R.; Ferracin, Paolo; Hafalia, A. R.; Sabbi, GianLuca; Ghosh, Arup; Wanderer, Peter

    2008-08-17

    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 1.9 K to 4.5 K.

  16. Fourier transform spectrometer remote sensing of O2 A-band electric quadrupole transitions

    NASA Astrophysics Data System (ADS)

    Miller, Charles E.; Wunch, Debra

    2012-07-01

    We observed electric quadrupole transitions in the O2 A-band, b1Σg+←X3Σg-(0,0), in high solar zenith angle atmospheric spectra recorded with the high-resolution solar-viewing Fourier transform spectrometer at Park Falls, WI. We identified 12 ΔN=±3 transitions for the first time, including the first detection of NO-branch transitions and extended the TS-branch observations of Brault [J Mol Spectrosc 1980;80:384-8] up to N″=23. Additionally, we observed six electric quadrupole transitions of the ΔN=-1 PO-branch. These observations demonstrate the excellent sensitivity and long-term stability of the new generation of solar-viewing Fourier transform spectrometers.

  17. The Study of Single Nb3Sn Quadrupole Coils Using a Magnetic Mirror Structure

    SciTech Connect

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

    2010-07-30

    Several 90-mm quadrupole coils made of 0.7-mm Nb{sub 3}Sn strand based on the 'Restack Rod Process' (RRP) of 108/127 design, with cored and non-cored cables and different cable insulation, were fabricated and individually tested at Fermilab using a test structure designed to provide a quadrupole magnetic field environment. The coils were instrumented with voltage taps and strain gauges to study quench performance and mechanical properties. The Nb{sub 3}Sn strand and cable parameters, the coil fabrication details, the mirror model assembly procedure and test results at temperatures of 4.5 K and 1.9 K are reported and discussed.

  18. Vibration Measurements to Study the Effect of Cryogen Flow in Superconducting Quadrupole.

    SciTech Connect

    He,P.; Anerella, M.; aydin, S.; Ganetis, G. Harrison, M.; Jain, A.; Parker, B.

    2007-06-25

    The conceptual design of compact superconducting magnets for the International Linear Collider final focus is presently under development. A primary concern in using superconducting quadrupoles is the potential for inducing additional vibrations from cryogenic operation. We have employed a Laser Doppler Vibrometer system to measure the vibrations in a spare RHIC quadrupole magnet under cryogenic conditions. Some preliminary results of these studies were limited in resolution due to a rather large motion of the laser head as well as the magnet. As a first step towards improving the measurement quality, a new set up was used that reduces the motion of the laser holder. The improved setup is described, and vibration spectra measured at cryogenic temperatures, both with and without helium flow, are presented.

  19. Design and construction of an electrostatic quadrupole doublet lens for nuclear microprobe application

    NASA Astrophysics Data System (ADS)

    Manuel, Jack E.; Szilasi, Szabolcs Z.; Phillips, Dustin; Dymnikov, Alexander D.; Reinert, Tilo; Rout, Bibhudutta; Glass, Gary A.

    2017-08-01

    An electrostatic quadrupole doublet lens system has been designed and constructed to provide strong, mass-independent focusing of 1-3 MeV ions to a 1 μm2 spot size. The electrostatic doublet consists of four sets of gold electrodes deposited on quartz rods that are positioned in a precision machined rigid frame. The 38 mm electrodes are fixed in a quadrupole doublet arrangement having a bore diameter of 6.35 mm. The coating process allows uniform, 360° coverage with minimal edge defects. Determined via optical interferometry, typical surface roughness is 6 nm peak to valley. Radial and coaxial alignment of the electrodes within the frame is accomplished by using a combination of rigid and adjustable mechanical supports. Axial alignment along the ion beam is accomplished via external manipulators. COMSOL Multiphysics® v5.2 and Propagate Rays and Aberrations by Matrices (PRAM) were used to simulate ion trajectories through the system.

  20. Analysis of manifestation of strong quadrupole light-molecule interaction in the SEHR spectra

    SciTech Connect

    Polubotko, A. M.

    2011-11-15

    It is demonstrated that appearance of strong lines in surface-enhanced hyper-Raman (SEHR) spectra of phenazine and pyrazine, which are associated with totally symmetric vibrations, as well as other details of these spectra, can be explained using the dipole-quadrupole theory. The main point of this theory is the concept of strong quadrupole interaction of light with molecules, which arises in surface fields strongly varying in space near a rough metal surface. The theoretical results make it possible to correctly interpret the SEHR spectra of phenazine and pyrazine (namely, the emergence of the strong lines due to totally symmetric vibrations that are forbidden in usual hyper-Raman scattering), as well as other lines in the spectrum.

  1. Dynamical map for combined function magnets with solenoid, dipole, and quadrupole fields

    SciTech Connect

    Venturini, Marco; Wolski, Andy

    2004-06-30

    The interaction regions of colliders invariably include strong solenoid fields. Where quadrupoles and dipoles are embedded in the solenoid, the beam dynamics in the combined fields can be complicated to model using the traditional approach of interleaving slices of the different fields. The complexity increases if the design trajectory is offset from the magnetic axis; this is the case, for example, in PEP-II. In this paper, we present maps for combined solenoid, dipole and quadrupole fields that provide a much simpler alternative to the traditional approach, and show that the deviation of the design trajectory from the magnetic axis can be handle in a straightforward manner. We illustrate the techniques presented by reference to the PEP-II interaction region.

  2. Ab initio Study of Nuclear Quadrupole Interactions in Selenium and Tellurium

    NASA Astrophysics Data System (ADS)

    Maharjan, N. B.; Paudyal, D. D.; Mishra, D. R.; Byahut, S. P.; Cho, Hwa-Suck; Scheicher, R. H.; Jeong, Junho; Das, T. P.

    2004-03-01

    We are systematically studying the influence of impurities in calcogenide glasses on the glass transition temperature using the first-principles Hartree-Fock cluster method. Results of our calculations on the electronic structures of pure selenium and tellurium chain systems, and with Te and Se impurities respectively, will be reported. By comparing the theoretically obtained nuclear quadrupole interaction (NQI) tensors for ^77Se and ^125Te with available experimental NQI tensors, we were able to test the accuracy of the calculated electronic structures. Good agreement for both the pure and the impurity systems has been found. We have also studied ^125Te NQI tensors in Te-Thiourea and compared our result with experimental data to check on the choice of the ^125Te quadrupole moment used.

  3. Magnetic fringe field interference between the quadrupole and corrector magnets in the CSNS/RCS

    NASA Astrophysics Data System (ADS)

    Yang, Mei; Kang, Wen; Deng, Changdong; Sun, Xianjing; Li, Li; Wu, Xi; Gong, Lingling; Cheng, Da; Zhu, Yingshun; Chen, Fusan

    2017-03-01

    The Rapid Cycling Synchrotron (RCS) of the China Spallation Neutron Source (CSNS) employs large aperture quadrupole and corrector magnets with small aspect ratios and relatively short iron to iron separations; so the fringe field interference becomes serious which results in integral field strength reduction and extra field harmonics. We have performed 3D magnetic field simulations to investigate the magnetic field interference in the magnet assemblies and made some adjustments on the magnet arrangement. The Fourier analysis is used to quantify the integral gradient reduction and field harmonic changes of the quadrupole magnets. Some magnetic field measurements are undertaken to verify the simulation results. The simulation details and the major results are presented in this paper.

  4. 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. © 2011 American Institute of Physics

  5. Search for Quadrupole Strength in the Electroexcitation of the Δ+\\(1232\\)

    NASA Astrophysics Data System (ADS)

    Mertz, C.; Vellidis, C. E.; Alarcon, R.; Barkhuff, D. H.; Bernstein, A. M.; Bertozzi, W.; Burkert, V.; Chen, J.; Comfort, J. R.; Dodson, G.; Dolfini, S.; Dow, K.; Farkhondeh, M.; Finn, J. M.; Gilad, S.; Gothe, R. W.; Jiang, X.; Joo, K.; Kaloskamis, N. I.; Karabarbounis, A.; Kelly, J. J.; Kowalski, S.; Kunz, C.; Lourie, R. W.; McIntyre, J. I.; Milbrath, B. D.; Miskimen, R.; Mitchell, J. H.; Papanicolas, C. N.; Perdrisat, C. F.; Sarty, A. J.; Shaw, J.; Soong, S.-B.; Tieger, D.; Tschalær, C.; Turchinetz, W.; Ulmer, P. E.; van Verst, S.; Warren, G. A.; Weinstein, L. B.; Williamson, S.; Woo, R. J.; Young, A.

    2001-04-01

    High-precision 1H\\(e,e'p\\)π0 measurements at Q2 = 0.126 \\(GeV/c\\)2 are reported, which allow the determination of quadrupole amplitudes in the γ*N-->Δ transition; they simultaneously test the reliability of electroproduction models. The derived quadrupole-to-dipole ( I = 3/2) amplitude ratios, RSM = \\(-6.5+/-0.2stat+sys+/-2.5mod\\)% and REM = \\(-2.1+/-0.2stat+sys+/-2.0mod\\)%, 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.

  6. A Super Strong Permanent Magnet Quadrupole for the Final Focus in a Linear Collider

    SciTech Connect

    Mihara, T.

    2004-12-06

    A super strong permanent magnet quadrupole (PMQ) was fabricated and tested. It has an integrated strength of 28.5T with overall length of 10 cm and a 7mm bore radius. Two drawbacks should be considered to this NdFeB based PMQ: the negative temperature coefficient of its field strength and its fixed strength. A thermal compensation material was added and tested to cure the first problem. The correct amount was determined to compensate the PMQ's temperature coefficient. The required field variability can be obtained by slicing magnet into pieces along the beamline direction and rotating these slices. But this technique may lead to movement of the magnetic center and introduction of a skew quadrupole component when the strength is varied.

  7. 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 (η) for the nucleobases in the various environments. Trends in e^2qQ and η 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)

  8. Group theoretical classification of halogen nuclear quadrupole resonance spectra of distorted tetragonal antifluorite crystals

    NASA Astrophysics Data System (ADS)

    Morra, Rose M.; Armstrong, Robin L.

    A classification of the patterns of halogen nuclear quadrupole resonance lines resulting from distortions of the tetragonal R 2MX 6 structures C4 h5( I4/ m) and D4 h6( P4/ mnc) is given. Formal methods of group thepry are used to identify low symmetry space groups with the symmetries of vectors in an irreducible representation space of the high symmetry space group. Classification charts are presented which permit the identification of those space groups and primary order parameters which are compatible with particular halogen nuclear quadrupole resonance spectra. The discussion is limited to structural phase transitions involving the points of symmetry in the Brillouin zones of the high temperature phases. The sequences of structural transitions in K 2ReCl 6 and (NH 4) 2SnBr 6 are discussed as illustrations of the use of these charts.

  9. Metabolite profiles of epimedin B in rats by ultraperformance liquid chromatography/quadrupole-time-of-flight mass spectrometry.

    PubMed

    Cui, Li; Sun, E; Zhang, Zhenhai; Qian, Qian; Tan, Xiaobin; Xu, Fengjuan; Jia, Xiaobin

    2013-04-17

    In this work, the metabolite profiles of epimedin B in rat feces, bile, urine, and plasma were qualitatively investigated, and the possible metabolic pathways of epimedin B were subsequently proposed. After oral administration of epimedin B at a single dose of 80 mg/kg, rat biological samples were collected and pretreated by protein precipitation. Then, these pretreated samples were injected into an Acquity ultraperformance liquid chromatography BEH C₁₈ column with mobile phase consisting of 0.1% formic acid-water and 0.1% formic acid-acetonitrile and detected by ultraperformance liquid chromatography/quadrupole-time-of-flight mass spectrometry. In all, 43 metabolites were identified in the biosamples. Of these, 13, including F5, F7, F16-F18, D5-D7, D9, N5, N7, M1, and M3, were to our knowledge reported for the first time. The results indicated that epimedin B was metabolized via desugarization, dehydrogenation, hydrogenation, hydroxylation, demethylation, glucuronidation, and glycosylation pathways in vivo. Specific hydrolysis of 7-O-glucosides in the gut lumen and glucuronic acid conjugation in the liver were considered as the main physiologic processes of epimedin B. This study revealed the possible metabolite profiles of epimedin B in rats.

  10. Quadrupole and scissors modes and nonlinear mode coupling in trapped two-component Bose-Einstein condensates

    SciTech Connect

    Kasamatsu, Kenichi; Tsubota, Makoto; Ueda, Masahito

    2004-04-01

    We theoretically investigate quadrupolar collective excitations in two-component Bose-Einstein condensates and their nonlinear dynamics associated with harmonic generation and mode coupling. Under the Thomas-Fermi approximation and the quadratic polynomial ansatz for density fluctuations, the linear analysis of the superfluid hydrodynamic equations predicts excitation frequencies of three normal modes constituted from monopole and quadrupole oscillations, and those of three scissors modes. These six modes are bifurcated into in-phase and out-of-phase modes by the intercomponent interaction, yielding the nonlinear dynamics that are absent in a single-component condensate. We obtain analytically the resonance conditions for the second-harmonic generation in terms of the trap aspect ratio and the strength of intercomponent interaction. The numerical simulation of the coupled Gross-Pitaevskii equations vindicates the validity of the analytical results and reveals the dynamics of the second-harmonic generation and nonlinear mode coupling that lead to nonlinear oscillations of the condensate with damping and recurrence reminiscent of the Fermi-Pasta-Ulam problem.

  11. Investigation on metabolism and pharmacokinetics of triclosan in rat plasma by using UPLC-triple quadrupole MS.

    PubMed

    Wu, Jianlin; Yue, Hao; Cai, Zongwei

    2009-09-01

    Triclosan has been widely used as a disinfectant in human health care products. Although this particular chemical is less toxic, its biotransformation products might have toxicity to human. Therefore, understanding the pharmacokinetics and metabolism of triclosan in animal and human body is important. Plasma samples from SD rats collected after the oral administration of 5 mg/kg triclosan were analyzed by ultra performance liquid chromatography (UPLC)-triple quadrupole mass spectrometry (TQMS) to support the pharmacokinetic study of triclosan. The method development was conducted with selected-ion-recording (SIR, also called SIM for selected-ion-monitoring) mode in ESI-MS and multiple-ion-monitoring (MRM) mode in MS/MS and the obtained results were compared. While MRM provided lower detection limits, its other method validation parameters were worse than those of SIR due to the poor fragmentation of triclosan. The developed SIR method provided limit of quantification of 10.8 ng/mL in plasma. The recovery, accuracy, precision and repeatability were satisfactory. The pharmacokinetic data of triclosan in the rats were presented including the half time of elimination that was (48.5 +/- 10.5) h, indicating that the elimination of triclosan in the rat was slow. Two hydroxylated and sulfonated triclosan, one glucuronidated triclosan, and one sulfonated triclosan were identified in the rat plasma samples.

  12. Real-time quadrupole mass spectrometer analysis of gas in boreholefluid samples acquired using the U-Tube sampling methodology

    SciTech Connect

    Freifeld, Barry M.; Trautz, Robert C.

    2006-01-11

    Sampling of fluids in deep boreholes is challenging becauseof the necessity to minimize external contamination and maintain sampleintegrity during recovery. The U-tube sampling methodology was developedto collect large volume, multiphase samples at in situ pressures. As apermanent or semi-permanent installation, the U-tube can be used forrapidly acquiring multiple samples or it may be installed for long-termmonitoring applications. The U-tube was first deployed in Liberty County,TX to monitor crosswell CO2 injection as part of the Frio CO2sequestration experiment. Analysis of gases (dissolved or separate phase)was performed in the field using a quadrupole mass spectrometer, whichserved as the basis for determining the arrival of the CO2 plume. Thepresence of oxygen and argon in elevated concentrations, along withreduced methane concentration, indicate sample alteration caused by theintroduction of surface fluids during borehole completion. Despiteproducing the well to eliminate non-native fluids, measurementsdemonstrate that contamination persists until the immiscible CO2injection swept formation fluid into the observationwellbore.

  13. Performance of the first short model 150 mm aperture Nb$_3$Sn Quadrupole MQXFS for the High- Luminosity LHC upgrade

    SciTech Connect

    Chlachidze, G.; et al.

    2016-08-30

    The US LHC Accelerator Research Program (LARP) and CERN combined their efforts in developing Nb3Sn magnets for the High-Luminosity LHC upgrade. The ultimate goal of this collaboration is to fabricate large aperture Nb3Sn quadrupoles for the LHC interaction regions (IR). These magnets will replace the present 70 mm aperture NbTi quadrupole triplets for expected increase of the LHC peak luminosity by a factor of 5. Over the past decade LARP successfully fabricated and tested short and long models of 90 mm and 120 mm aperture Nb3Sn quadrupoles. Recently the first short model of 150 mm diameter quadrupole MQXFS was built with coils fabricated both by the LARP and CERN. The magnet performance was tested at Fermilab’s vertical magnet test facility. This paper reports the test results, including the quench training at 1.9 K, ramp rate and temperature dependence studies.

  14. High precision measurement of the 11Li and 9Li quadrupole moment ratio using zero-field β-NQR

    NASA Astrophysics Data System (ADS)

    Voss, A.; Pearson, M. R.; Buchinger, F.; Crawford, J. E.; Kiefl, R. F.; Levy, C. D. P.; MacFarlane, W. A.; Mané, E.; Morris, G. D.; Shelbaya, O. T. J.; Song, Q.; Wang, D.

    2014-01-01

    The ratio of electric quadrupole moments of 11Li and 9Li was measured using the zero-field β-detected nuclear quadrupole resonance technique at Triumf-Isac. The precision on the ratio Q11/Q9 = 1.0775(12) was improved by more than one order of magnitude and an absolute value for the quadrupole moment of 11Li was inferred. Systematic effects, as argued here, are not expected to contribute to the ratio on this scale. The zero-field spin-lattice relaxation time for 8Li implanted within SrTiO3 at 295 K in zero-field was found to be T1 = 1.73(2) s. A comparison of the quadrupole moments of 9, 11Li and their ratio is made with the latest models, however, no conclusion may yet be drawn owing to the size of the theoretical uncertainties.

  15. Collections Conservation.

    ERIC Educational Resources Information Center

    DeCandido, Robert

    Collections conservation is an approach to the preservation treatment of books and book-like materials that is conceptualized and organized in terms of large groups of materials. This guide is intended to enable a library to evaluate its current collections conservation activities. The introduction describes collections conservation and gives…

  16. Finite Element Model of Training in the superconducting quadrupole magnet SQ02

    SciTech Connect

    Caspi, Shlomo; Ferracin, Paolo

    2007-11-01

    This paper describes the use of 3D finite element models to study training in superconducting magnets. The simulations are used to examine coil displacements when the electromagnetic forces are cycled, and compute the frictional energy released during conductor motion with the resulting temperature rise. A computed training curve is then presented and discussed. The results from the numerical computations are compared with test results of the Nb{sub 3}Sn racetrack quadrupole magnet SQ02.

  17. Analytical approach for description of ion motion in quadrupole mass spectrometer.

    PubMed

    Baranov, Vladimir I

    2003-08-01

    Implementation of the analytical method of the solution of the Mathieu equation in conjunction with the algebraic presentation of Mathieu functions is discussed in this work. This approach is used for the analytical expression of fundamental properties of the quadrupole field such as ion trajectory stability and transmission. Extensive comparison with the matrix method is presented with demonstration of the fundamental advantages of the analytical method. However, contrary to the matrix method, the analytical method is limited to the cos trapping waveforms.

  18. Linear radio frequency quadrupole for the cooling and bunching of radioactive ion beams

    SciTech Connect

    Darius, G.; Ban, G.; Bregeault, J.; Delahaye, P.; Desrues, Ph.; Durand, D.; Flechard, X.; Herbane, M.; Labalme, M.; LeBrun, Ch.; Lienard, E.; Mauger, F.; Merrer, Y.; Mery, A.; Naviliat-Cuncic, O.; Szerypo, J.; Vallerand, Ph.; Vandamme, Ch.

    2004-11-01

    A linear radio frequency quadrupole has been built for the transport, cooling, and bunching of radioactive ions extracted from an ECR source. The device uses the buffer gas cooling technique and was designed such as to extend the technique for the cooling of very light ions using H{sub 2} as buffer gas. We describe here the technical specifications of the device and present results of the first tests concerning the cooling and bunching of stable ions.

  19. Modified quadrupole mass analyzer RGA-100 for beam plasma research in forevacuum pressure range

    SciTech Connect

    Zolotukhin, D. B.; Tyunkov, A. V.; Yushkov, Yu. G.; Oks, E. M.

    2015-12-15

    The industrial quadrupole RGA-100 residual gas analyzer was modified for the research of electron beam-generated plasma at forevacuum pressure range. The standard ionizer of the RGA-100 was replaced by three electrode extracting unit. We made the optimization of operation parameters in order to provide the maximum values of measured currents of any ion species. The modified analyzer was successfully tested with beam plasma of argon, nitrogen, oxygen, and hydrocarbons.

  20. Mechanical and electromagnetic design of the SSC QSE101 quadrupole ends

    SciTech Connect

    Orrell, D.; Nobrega, F.; Lilly, J.; Snitchler, G.; Jayakumar, J.; Venkatraman, V. ); Brandt, J.S. )

    1991-06-01

    The SSC collider magnets feature grouped ends in which cables of a particular coil remain stacked together as they are gent around the end. methods have been developed to form the ends in such a way that mechanical stresses are lowered and field quality is optimized. This paper discusses techniques of end turn design and presents calculations of harmonics and peak fields for the SSC quadrupole QSE101. 5 refs., 9 figs.

  1. Measurements of the H2 4-0 quadrupole bands of Uranus and Neptune

    SciTech Connect

    Smith, W.H.; Macy, W. Jr.

    1980-01-01

    It is found that the equivalent widths of the lines of the 4-0 H2 quadrupole band on Uranus and Neptune are substantially smaller than the values found by some previous observers. An analysis of the results based on a range of atmospheric models yields H2 abundances of 240 + or - 60 km-amagats for Uranus and greater than approximately 200 km amagats for Neptune.

  2. 14N Quadrupole Coupling in the Microwave Spectra of N-Vinylformamide

    NASA Astrophysics Data System (ADS)

    Kannengießer, Raphaela; Stahl, Wolfgang; Nguyen, Ha Vinh Lam; Bailey, William C.

    2016-06-01

    The microwave spectra of two conformers, trans and cis, of the title compound were recorded using two molecular beam Fourier transform microwave spectrometers operating in the frequency range 2 GHz to 40 GHz, and aimed at analysis of their 14N quadrupole hyperfine structures. Rotational constants, centrifugal distortion constants, and nuclear quadrupole coupling constants (NQCCs) χaa and χbb - χcc, were all determined with very high accuracy. Two fits including 176 and 117 hyperfine transitions were performed for the trans and cis conformers, respectively. Standard deviations of both fits are close to the measurement accuracy of 2 kHz. The NQCCs of the two conformers are almost exactly the same, and are compared with values found for other saturated and unsaturated formamides. Complementary quantum chemical calculations - MP2/6-311++G(d,p) rotational constants, MP2/cc-pVTZ centrifugal distortion constants, and B3PW91/6-311+G(d,p)//MP2/6-311++G(d,p) nuclear quadrupole coupling constants - give spectroscopic parameters in excellent agreement with the experimental parameters. B3PW91/6-311+G(d,p) calculated electric field gradients, in conjunction with eQ/h = 4.599(12) MHz/a.u., yields more reliable NQCCs for formamides possessing conjugated π-electron systems than does the B3PW91/6-311+G(df,pd) model recommended in Ref., whereas this latter performs better for aliphatic formamides. We conclude from this that f-polarization functions on heavy atoms hinder rather than help with modeling of conjugated π-electron systems. W. C. Bailey, Chem. Phys., 2000, 252, 57 W. C. Bailey, Calculation of Nuclear Quadrupole Coupling Constants in Gaseous State Molecules, http://nqcc.wcbailey.net/index.html.

  3. Interfacing an aspiration ion mobility spectrometer to a triple quadrupole mass spectrometer

    SciTech Connect

    Adamov, Alexey; Viidanoja, Jyrki; Kaerpaenoja, Esko; Paakkanen, Heikki; Ketola, Raimo A.; Kostiainen, Risto; Sysoev, Alexey; Kotiaho, Tapio

    2007-04-15

    This article presents the combination of an aspiration-type ion mobility spectrometer with a mass spectrometer. The interface between the aspiration ion mobility spectrometer and the mass spectrometer was designed to allow for quick mounting of the aspiration ion mobility spectrometer onto a Sciex API-300 triple quadrupole mass spectrometer. The developed instrumentation is used for gathering fundamental information on aspiration ion mobility spectrometry. Performance of the instrument is demonstrated using 2,6-di-tert-butyl pyridine and dimethyl methylphosphonate.

  4. Rotating effects on the Landau quantization for an atom with a magnetic quadrupole moment

    SciTech Connect

    Fonseca, I. C.; Bakke, K.

    2016-01-07

    Based on the single particle approximation [Dmitriev et al., Phys. Rev. C 50, 2358 (1994) and C.-C. Chen, Phys. Rev. A 51, 2611 (1995)], the Landau quantization associated with an atom with a magnetic quadrupole moment is introduced, and then, rotating effects on this analogue of the Landau quantization is investigated. It is shown that rotating effects can modify the cyclotron frequency and breaks the degeneracy of the analogue of the Landau levels.

  5. Interfacing an aspiration ion mobility spectrometer to a triple quadrupole mass spectrometer

    NASA Astrophysics Data System (ADS)

    Adamov, Alexey; Viidanoja, Jyrki; Kärpänoja, Esko; Paakkanen, Heikki; Ketola, Raimo A.; Kostiainen, Risto; Sysoev, Alexey; Kotiaho, Tapio

    2007-04-01

    This article presents the combination of an aspiration-type ion mobility spectrometer with a mass spectrometer. The interface between the aspiration ion mobility spectrometer and the mass spectrometer was designed to allow for quick mounting of the aspiration ion mobility spectrometer onto a Sciex API-300 triple quadrupole mass spectrometer. The developed instrumentation is used for gathering fundamental information on aspiration ion mobility spectrometry. Performance of the instrument is demonstrated using 2,6-di-tert-butyl pyridine and dimethyl methylphosphonate.

  6. Vacuum polarization and quadrupole corrections to the hyperfine splitting of P-states in muonic deuterium

    NASA Astrophysics Data System (ADS)

    Martynenko, A. P.; Sorokin, V. V.

    2017-02-01

    On the basis of the quasipotential approach in quantum electrodynamics, we calculate vacuum polarization and quadrupole corrections in the first and second orders of perturbation theory in the hyperfine structure of P-states in muonic deuterium. All corrections are presented in integral form and are evaluated analytically and numerically. The obtained results can be used for the improvement of the transition frequencies between levels 2P and 2S.

  7. Focusing properties of a three-element quadrupole lens system and its stigmatic focusing behaviour

    NASA Astrophysics Data System (ADS)

    Zafar, Yu.

    The focusing properties of a three-element quadrupole lens system (triplet) have been studied in its general thick-lens form, and analytical expressions of corresponding matrix elements have been obtained. A graphical method has been utilized to determine the stigmatic focusing region of the triplet system generally, and in the special case of electrostatic triplet system installed in 'on-line SPIN-3 facility' in YASNAPP-2, JINR.

  8. Rotating effects on the Landau quantization for an atom with a magnetic quadrupole moment.

    PubMed

    Fonseca, I C; Bakke, K

    2016-01-07

    Based on the single particle approximation [Dmitriev et al., Phys. Rev. C 50, 2358 (1994) and C.-C. Chen, Phys. Rev. A 51, 2611 (1995)], the Landau quantization associated with an atom with a magnetic quadrupole moment is introduced, and then, rotating effects on this analogue of the Landau quantization is investigated. It is shown that rotating effects can modify the cyclotron frequency and breaks the degeneracy of the analogue of the Landau levels.

  9. Trapping, retention and laser cooling of Th3+ ions in a multisection linear quadrupole trap

    NASA Astrophysics Data System (ADS)

    Borisyuk, P. V.; Vasil'ev, O. S.; Derevyashkin, S. P.; Kolachevsky, N. N.; Lebedinskii, Yu. Yu.; Poteshin, S. S.; Sysoev, A. A.; Tkalya, E. V.; Tregubov, D. O.; Troyan, V. I.; Khabarova, K. Yu.; Yudin, V. I.; Yakovlev, V. P.

    2017-06-01

    A multisection linear quadrupole trap for Th3+ ions is described. Multiply charged ions are obtained by the laser ablation method. The possibility of trapping and retention of ˜103 ions is demonstrated in macroscopic time scales of ˜30 s. Specific features of cooling Th3+ ions on the electron transitions with wavelengths of 1088, 690 and 984 nm in Th3+ ion are discussed; a principal scheme of a setup for laser cooling is presented.

  10. Deterioration of the skew quadrupole moment in Tevatron dipoles over time

    SciTech Connect

    Syphers, M.J.; Harding, D.J.; /Fermilab

    2005-05-01

    During the 20 years since it was first commissioned, the Fermilab Tevatron has developed strong coupling between the two transverse degrees of freedom. A circuit of skew quadrupole magnets is used to correct for coupling and, though capable, its required strength has increased since 1983 by more than an order of magnitude. In more recent years changes to the Tevatron for colliding beams operation have altered the skew quadrupole corrector distribution and strong local coupling become evident, often encumbering routine operation during the present physics run. Detailed magnet measurements were performed on each individual magnet during construction, and in early 2003 it was realized that measurements could be performed on the magnets in situ which could determine coil movements within the iron yoke since the early 1980's. It was discovered that the superconducting coils had become vertically displaced relative to their yokes since their construction. The ensuing systematic skew quadrupole field introduced by this displacement accounts for the required corrector settings and observed beam behavior. An historical account of the events leading to this discovery and progress toward its remedy are presented.

  11. Rotational spectra of methyl ethyl and methyl propyl nitrosamines. Conformational assignment, internal rotation and quadrupole coupling

    NASA Astrophysics Data System (ADS)

    Walker, A. R. Hight; Lou, Qi; Bohn, Robert K.; Novick, Stewart E.

    1995-02-01

    A structural determination of two carcinogenic nitrosamines, methyl ethyl and methyl propyl nitrosamine, was performed. Microwave spectra were gathered from both a Stark cell spectrometer and a pulsed jet Fabry-Perot Fourier transform microwave spectrometer. Each rotational transition is split into quadrupole hyperfine components by two nitrogen nuclei. This quadrupole pattern is doubled by a low barrier methyl rotor which produces resolvable A and E states. Rotational spectra were assigned for one conformer of methyl ethyl nitrosamine and two conformers of methyl propyl nitrosamine. The lowest energy conformers of each compound, according to empirical force field calculations, were assigned. The structure found for methyl ethyl nitrosamine has the nitrosyl oxygen on the methyl side with the terminal methyl group of the ethyl chain in the gauche position (OMG). Both conformers of methyl propyl nitrosamine have the same skeletal structure as the methyl ethyl compound; one conformer has the terminal methyl of the propyl group in the anti position (OMGA) while the other conformer has this methyl in the gauche position (OMGG -). Rotational constants and quadrupole coupling constants are reported for each assigned species. A barrier to internal rotation of the N-methyl group in each compound is also reported.

  12. Translationally invariant semi-classical electrodynamics of magnetic media to electric octopole-magnetic quadrupole order

    NASA Astrophysics Data System (ADS)

    Welter, A.; Raab, R. E.; de Lange, O. L.

    2013-02-01

    We consider semi-classical macroscopic electrodynamics that is translationally invariant (independent of the choice of an arbitrary, implicit set of coordinate origins for molecule-fixed axes) for linear, homogeneous, anisotropic media interacting with harmonic, plane electromagnetic waves. We extend a previous formulation at electric octopole-magnetic quadrupole order to include media comprising magnetic molecules (those possessing both time-even and time-odd properties). This requires two additional invariant, time-odd molecular polarizabilities. Overall, the electrodynamics depends on 10 invariant polarizabilities—5 time even (one each of electric dipole and electric quadrupole-magnetic dipole order, and three of electric octopole-magnetic quadrupole order) and 5 time odd (one, two, and two, respectively)—that are required for the description of linear transmission and reflection phenomena, and material constants. The two additional time-odd polarizabilities account for certain predicted effects, and one of them contributes to the inverse ac permeability of magnetic media. The results are presented in a form that is suitable for numerical computation.

  13. Dynamics of vortex quadrupoles in nonrotating trapped Bose-Einstein condensates.

    PubMed

    Yang, Tao; Hu, Zhi-Qiang; Zou, Shan; Liu, Wu-Ming

    2016-07-28

    Dynamics of vortex clusters is essential for understanding diverse superfluid phenomena. In this paper, we examine the dynamics of vortex quadrupoles in a trapped two-dimensional (2D) Bose-Einstein condensate. We find that the movement of these vortex-clusters fall into three distinct regimes which are fully described by the radial positions of the vortices in a 2D isotropic harmonic trap, or by the major radius (minor radius) of the elliptical equipotential lines decided by the vortex positions in a 2D anisotropic harmonic trap. In the "recombination" and "exchange" regimes the quadrupole structure maintains, while the vortices annihilate each other permanently in the "annihilation" regime. We find that the mechanism of the charge flipping in the "exchange" regime and the disappearance of the quadrupole structure in the "annihilation" regime are both through an intermediate state where two vortex dipoles connected through a soliton ring. We give the parameter ranges for these three regimes in coordinate space for a specific initial configuration and phase diagram of the vortex positions with respect to the Thomas-Fermi radius of the condensate. We show that the results are also applicable to systems with quantum fluctuations for the short-time evolution.

  14. Larp Nb3Sn Quadrupole Magnets for the Lhc Luminosity Upgrade

    NASA Astrophysics Data System (ADS)

    Ferracin, P.

    2010-04-01

    The US LHC Accelerator Research Program (LARP) is a collaboration between four US laboratories (BNL, FNAL, LBNL, and SLAC) aimed at contributing to the commissioning and operation of the LHC and conducting R&D on its luminosity upgrade. Within LARP, the Magnet Program's main goal is to demonstrate that Nb3Sn superconducting magnets are a viable option for a future upgrade of the LHC Interaction Regions. Over the past four years, LARP has successfully fabricated and tested several R&D magnets: 1) the subscale quadrupole magnet SQ, to perform technology studies with 300 mm long racetrack coils, 2) the technology quadrupole TQ, to investigate support structure behavior with 1 m long cos 2θ coils, and 3) the long racetrack magnet LR, to test 3.6 m long racetrack coils. The next milestone consists in the fabrication and test of the 3.7 m long quadrupole magnet LQ, with the goal of demonstrating that Nb3Sn technology is mature for use in high energy accelerators. After an overview of design features and test result of the LARP magnets fabricated so far, this paper focuses on the status of the fabrication of LQ: we describe the production of the 3.4 m long cos 2θ coils, and the of the qualification support structure. Finally, the status of the development of the next 1 m long model HQ, conceived to explore stress and field limits of Nb3Sn superconducting, magnets, is presented.

  15. Cryo-technical design aspects of the superconducting SIS100 quadrupole doublet modules

    SciTech Connect

    Meier, J. P.; Bleile, A.; Fischer, E.; Hess, G.; Macavei, J.; Spiller, P.

    2014-01-29

    The FAIR project was initiated to build an international accelerator and experimental facility for basic research activities in various fields of modern physics. The core component of the project will be the SIS100 heavy ion accelerator, producing heavy ion beams of uniquely high intensities and qualities. The superconducting main quadrupoles and corrector magnets are assembled within complex quadrupole doublet modules (QDMs), combining two superconducting quadrupole (focusing and defocusing), sextupole and steering magnets in one cryostat. In addition a cryo-catcher, a beam position monitor and a cold beam pipe will be integrated. In accordance with the magnet lattice structure, the QDM series for the SIS100 consists of four main families composed of eleven different configurations. The common technical feature of all configurations is a sophisticated common girder structure, mechanically integrating all functional components in one cold mass and being suspended in a corresponding cryostat system. The requirements to position preservation during thermal cycling are to be fulfilled by a precise and stable support of the functional elements, as well as by a reliable, reproducible and stable cold mass suspension system. The main design aspects of the QDMs will be discussed as a result of these requirements.

  16. Quadrupole contributions to 10,11B + 16O elastic scattering

    NASA Astrophysics Data System (ADS)

    Parks, L. A.; Stanley, D. P.; Courtney, L. H.; Kemper, K. W.

    1980-01-01

    Elastic scattering angular distributions have been measured for the systems 10B + 16O at EL=33.7, 41.6, and 49.5 MeV and 11B + 16O at EL=41.6 and 49.5 MeV. The 10B and 11B data are oscillatory and similar for angles less than 50° c.m. For angles greater than 50° c.m., the oscillations in the 10B data are damped and the data stop decreasing with increasing angle. Elastic scattering angular distributions have been calculated for 10,11B + 16O with the coupling to the ground-state quadrupole moment included explicitly. Potentials which describe the scattering are extracted with the double folding model. It is found that the quadrupole coupling is necessary to explain the difference in 10B and 11B scattering from 16O. NUCLEAR REACTIONS 16O (10B, 10B) 16O, EL=33.7, 41.6, and 49.5 MeV, 16O (11B, 11B) 16O, EL=41.6 and 49.5 MeV. Measured σ(θ), deduced Woods-Saxon, and double-folding model parameters. Coupled channels calculations for the ground-state quadrupole moment contributions.

  17. Radiation and Thermal Analysis of Superconducting Quadrupoles in the Interaction Region of Linear Collider

    SciTech Connect

    Drozhdin, A.I.; Kashikhin, V.V.; Kashikhin, V.S.; Lopes, M.L.; Mokhov, N.V.; Zlobin, A.V.; Seryi, Andrei; /SLAC

    2011-10-14

    Radiation heat deposition in the superconducting magnets of the Interaction Region (IR) of a linear collider can be a serious issue that limits the magnet operating margins and shortens the material lifetime. Radiation and thermal analyses of the IR quadrupoles in the incoming and extraction beam lines of the ILC are performed in order to determine the magnet limits. This paper presents an analysis of the radial, azimuthal and longitudinal distributions of heat deposition in the incoming and disrupted beam doublets. Operation margins of the magnets based on NbTi superconductor are calculated and compared. The radiation and thermal analysis of the ILC IR quadrupoles based on Rutherford type cables was performed. It was found that the peak radiation heat deposition takes place in the second extraction quadrupole QFEX2. The maximum power density in the coil is {approx}17mW/g. This is rather high, comparing to the proton machines (LHC). However, the fast radial decay of the heat deposition together with the high thermal conductivity of the Rutherford type cable limits the coil temperatures to a moderate level. It was determined that both 2-layer and 4-layer QFEX2 magnet designs have thermal margins of a factor of {approx}4 at the nominal gradient of 31.3 T/m. Because of the large margins, these magnets can easily accommodate possible changes in the IR optics and heat deposition levels.

  18. Simulation of Thermographic Responses of Delaminations in Composites with Quadrupole Method

    NASA Technical Reports Server (NTRS)

    Winfree, William P.; Zalameda, Joseph N.; Howell, Patricia A.; Cramer, K. Elliott

    2016-01-01

    The application of the quadrupole method for simulating thermal responses of delaminations in carbon fiber reinforced epoxy composites materials is presented. The method solves for the flux at the interface containing the delamination. From the interface flux, the temperature at the surface is calculated. While the results presented are for single sided measurements, with ash heating, expansion of the technique to arbitrary temporal flux heating or through transmission measurements is simple. The quadrupole method is shown to have two distinct advantages relative to finite element or finite difference techniques. First, it is straight forward to incorporate arbitrary shaped delaminations into the simulation. Second, the quadrupole method enables calculation of the thermal response at only the times of interest. This, combined with a significant reduction in the number of degrees of freedom for the same simulation quality, results in a reduction of the computation time by at least an order of magnitude. Therefore, it is a more viable technique for model based inversion of thermographic data. Results for simulations of delaminations in composites are presented and compared to measurements and finite element method results.

  19. Dynamic properties of bicellar lipid mixtures observed by rheometry and quadrupole echo decay.

    PubMed

    Flynn, Alanna; Ducey, Michael; Yethiraj, Anand; Morrow, Michael R

    2012-02-07

    In bicellar dispersions of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC), the transition from isotropic reorientation to partial orientational order, on warming, is known to coincide with a sharp increase in viscosity. In this work, cone-and-plate rheometry, (2)H NMR spectroscopy, and quadrupole echo decay observations have been used to obtain new insights into the dynamics of phases observed in bicellar DMPC/DHPC mixtures. Samples with 25% of the DMPC component deuterated were used to correlate rheological measurements with phase behavior observed by (2)H NMR spectroscopy. Mixtures containing only normal DMPC (DMPC/DHPC) or only chain perdeuterated DMPC (DMPC-d(54)/DHPC) were used to refine rheology and quadrupole echo decay measurements respectively. The viscosity peaked at 4-9 Pa·s, just above the isotropic-to-nematic transition, and then dropped as samples were warmed through the nematic-to-lamellar transition. Quadrupole echo decay times above the nematic-to-lamellar transition were significantly longer than typically observed in the liquid crystalline phase of saturated lipid multilamellar vesicles. This may indicate a damping of slow bilayer undulations resulting from the coupling of opposite bilayer surfaces by DHPC-lined pores.

  20. Quadrupole interactions: NMR, NQR, and in between from a single viewpoint.

    PubMed

    Bain, Alex D

    2017-03-01

    Nuclear spins with quantum numbers >1/2 can interact with a static magnetic field, or a local electric field gradient, to produce quantized energy levels. If the magnetic field interaction dominates, we are doing nuclear magnetic resonance (NMR). If the interaction of the nuclear electric quadrupole with electric field gradients is much stronger, this is nuclear quadrupole resonance (NQR). The two are extremes of a continuum, as the ratio of one interaction to the other changes. In this work, we look at this continuum from a single, unified viewpoint based on a Liouville-space approach: the direct method. This method does not require explicit operators and their commutators, unlike Hamiltonian methods. We derive both the quadrupole-perturbed NMR solution and also the Zeeman-perturbed NQR results. Furthermore, we examine the polarization of these signals, because this is different between pure NMR and pure NQR spectroscopy. Spin 3/2 is the focus here, but the approach is perfectly general and can be applied to any spin. Copyright © 2016 John Wiley & Sons, Ltd.