Journal articles: 'Nucleon axial charge'

1

Kojo, Toru. "Can the nucleon axial charge be ?" Nuclear Physics A 899 (February 2013): 76–106. http://dx.doi.org/10.1016/j.nuclphysa.2012.12.116.

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GAMBERG, LEONARD, and GARY R. GOLDSTEIN. "FLAVOR-SPIN SYMMETRY AND THE TENSOR CHARGE." International Journal of Modern Physics A 18, no. 08 (March 30, 2003): 1297–302. http://dx.doi.org/10.1142/s0217751x03014630.

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Exploiting an approximate phenomenological symmetry of the JPC = 1+- light axial vector mesons and using pole dominance, we calculate the flavor contributions to the nucleon tensor charge. The result depends on the decay constants of the axial vector mesons and their couplings to the nucleons.

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Kirchbach, M., D. O. Riska, and K. Tsushima. "The axial exchange charge operator and the nucleon-nucleon interaction." Nuclear Physics A 542, no. 4 (June 1992): 616–30. http://dx.doi.org/10.1016/0375-9474(92)90260-q.

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4

Birse, Michael C. "The axial charge of a nucleon in matter." Physics Letters B 316, no. 4 (October 1993): 472–75. http://dx.doi.org/10.1016/0370-2693(93)91030-q.

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Renner, D. B., R. G. Edwards, G. Fleming, Ph Hägler, J. W. Negele, K. Orginos, A. V. Pochinsky, D. G. Richards, and W. Schroers. "Calculation of the nucleon axial charge in lattice QCD." Journal of Physics: Conference Series 46 (September 1, 2006): 152–56. http://dx.doi.org/10.1088/1742-6596/46/1/021.

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6

He, Han-Xin, Nader Mobed, and Faqir C. Khanna. "The 1/Nc corrections to static properties of nucleons in the Skyrme model." Canadian Journal of Physics 66, no. 11 (November 1, 1988): 994–96. http://dx.doi.org/10.1139/p88-161.

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Corrections of O(1/Nc) to static properties of nucleons in the Skyrme model are calculated. The O(1/Nc) corrections due to quantization of collective coordinates are less than 4% for the axial charge and magnetic moment of the nucleon.

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Jang, Yong-Chull, Tanmoy Bhattacharya, Rajan Gupta, Huey-Wen Lin, and Boram Yoon. "Nucleon Axial and Electromagnetic Form Factors." EPJ Web of Conferences 175 (2018): 06033. http://dx.doi.org/10.1051/epjconf/201817506033.

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We present results for the isovector axial, induced pseudoscalar, electric, and magnetic form factors of the nucleon. The calculations were done using 2 + 1 + 1-flavor HISQ ensembles generated by the MILC collaboration with lattice spacings a ≈ 0.12, 0.09, 0.06 fm and pion masses Mπ ≈ 310, 220, 130 MeV. Excited-states contamination is controlled by using four-state fits to two-point correlators and by comparing two-versus three-states in three-point correlators. The Q2 behavior is analyzed using the model independent z-expansion and the dipole ansatz. Final results for the charge radii and magnetic moment are obtained using a simultaneous fit in Mπ, lattice spacing a and finite volume.

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8

Ali Khan, A., M. Göckeler, P. Hägler, T. R. Hemmert, R. Horsley, A. C. Irving, D. Pleiter, et al. "Axial and tensor charge of the nucleon with dynamical fermions." Nuclear Physics B - Proceedings Supplements 140 (March 2005): 408–10. http://dx.doi.org/10.1016/j.nuclphysbps.2004.11.320.

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9

Ohta, Shigemi, and Kostas Orginos. "Nucleon axial charge and structure functions with domain wall fermions." Nuclear Physics B - Proceedings Supplements 129-130 (March 2004): 296–98. http://dx.doi.org/10.1016/s0920-5632(03)02561-1.

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10

FRITZSCH, HARALD. "THE NUCLEON: ITS SPIN, AXIAL CHARGE AND THE CHIRAL SYMMETRY." Modern Physics Letters A 05, no. 23 (September 20, 1990): 1815–24. http://dx.doi.org/10.1142/s0217732390002079.

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11

HE, HAN-XIN. "TRANSVERSITY DISTRIBUTION AND TENSOR CHARGE OF THE NUCLEON." International Journal of Modern Physics A 18, no. 08 (March 30, 2003): 1289–96. http://dx.doi.org/10.1142/s0217751x03014629.

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We study the transversity distribution and the tensor charge of the nucleon based on the QCD sum rule approach. We also discuss the spin physics in the effective theory, and then analyse the quark contributions to the flavour-singlet axial charge and the tensor charge by means of the quark model. How to build a consistent nonperturbative approach for studying the spin physics and other hadronic physics at low-energy scale is also briefly introduced.

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12

Capitani, S., M. Della Morte, D. Djukanovic, G. M. von Hippel, J. Hua, B. Jäger, P. M. Junnarkar, H. B. Meyer, T. D. Rae, and H. Wittig. "Isovector axial form factors of the nucleon in two-flavor lattice QCD." International Journal of Modern Physics A 34, no. 02 (January 20, 2019): 1950009. http://dx.doi.org/10.1142/s0217751x1950009x.

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We present a lattice calculation of the nucleon isovector axial and induced pseudoscalar form factors on the CLS ensembles using [Formula: see text] dynamical flavors of nonperturbatively [Formula: see text]-improved Wilson fermions and an [Formula: see text]-improved axial current together with the pseudoscalar density. Excited-state effects in the extraction of the form factors are treated using a variety of methods, with a detailed discussion of their respective merits. The chiral and continuum extrapolation of the results is performed both using formulae inspired by Heavy Baryon Chiral Perturbation Theory (HBChPT) and a global approach to the form factors based on a chiral effective field theory (EFT) including axial vector mesons. Our results indicate that careful treatment of excited-state effects is important in order to obtain reliable results for the axial form factors of the nucleon, and that the main remaining error stems from the systematic uncertainties of the chiral extrapolation. As final results, we quote [Formula: see text], [Formula: see text], and [Formula: see text] for the axial charge, axial charge radius and induced pseudoscalar charge, respectively, where the first error is statistical and the second is systematic.

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13

CHENG, T. P., N. I. KOCHELEV, and VICENTE VENTO. "FURTHER COMMENTS ON A VANISHING SINGLET AXIAL VECTOR CHARGE." Modern Physics Letters A 14, no. 03 (January 30, 1999): 205–9. http://dx.doi.org/10.1142/s0217732399000249.

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The recent suggestion of a vanishing flavor-singlet axial-charge of nucleon due to a nontrivial vacuum structure is further amplified. A perturbative QCD discussion, applicable for the heavy quark contributions, relates it to the physics of the decoupling theorem. It is also shown that [Formula: see text] leads to a negative η′-meson-quark coupling, which has been found to be compatible with the chiral quark model phenomenology.

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14

Hatsuda, Tetsuo. "Tensor Charge of the Nucleon on a Lattice." Australian Journal of Physics 50, no. 1 (1997): 205. http://dx.doi.org/10.1071/p96030.

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The tensor charge of the nucleon, which will be measured in Drell-Yan processes in polarized proton–proton collisions at the RHIC, is studied in a quenched lattice QCD simulation. On the 163 × 20 lattice with β = 5·7, connected parts of the tensor charge are determined with small statistical error, while the disconnected parts are found to be small with relatively large error bars. The flavour-singlet tensor charge (δΣ = du + δd + δs) is not suppressed, as opposed to the flavour-singlet axial charge (ΔΣ = Δu + Δd + Δs).

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15

Negele, J. W., B. Bistrovic, R. G. Edwards, G. Fleming, Ph Hägler, K. Orginos, A. Pochinsky, D. B. Renner, D. G. Richards, and W. Schroers. "Hadron Structure from Lattice QCD." International Journal of Modern Physics A 21, no. 04 (February 10, 2006): 720–25. http://dx.doi.org/10.1142/s0217751x06031946.

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The structure of neutrons, protons, and other strongly interacting particles is now being calculated in full, unquenched lattice QCD with quark masses entering the chiral regime. This talk describes selected examples, including the nucleon axial charge, structure functions, electromagnetic form factors, the origin of the nucleon spin, the transverse structure of the nucleon, and the nucleon to Delta transition form factor.

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16

Liu, Keh-Fei. "Flavor-singlet axial charge of the nucleon and anomalous Ward identity." Physics Letters B 281, no. 1-2 (May 1992): 141–47. http://dx.doi.org/10.1016/0370-2693(92)90288-f.

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17

BARIK, N., S. N. JENA, and D. P. RATH. "PION-CLOUD EFFECTS ON THE ELECTROMAGNETIC PROPERTIES OF NUCLEONS IN A QUARK MODEL." International Journal of Modern Physics A 07, no. 27 (October 30, 1992): 6813–31. http://dx.doi.org/10.1142/s0217751x92003124.

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Incorporating corrections for the center-of-mass motion and pion-cloud effects the nucleon electromagnetic form factors [Formula: see text] are computed in an independent quark model based on the Dirac equation with a confining potential [Formula: see text] The static quantities like magnetic moment μN, charge radius [Formula: see text] and axial vector coupling constant (gA)n→peν of the nucleons computed in this model are in reasonable agreement with the experiment. The pseudoscalar and the pseudovector pion-nucleon coupling constants are obtained as gNNπ=13.52 and fNNπ=0.284, which are in excellent agreement with the experimental data.

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18

Horsley, R., Y. Nakamura, A. Nobile, P. E. L. Rakow, G. Schierholz, and J. M. Zanotti. "Nucleon axial charge and pion decay constant from two-flavor lattice QCD." Physics Letters B 732 (May 2014): 41–48. http://dx.doi.org/10.1016/j.physletb.2014.03.002.

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19

Li, Hong-na, and P. Wang. "Chiral extrapolation of nucleon axial charge g A in effective field theory." Chinese Physics C 40, no. 12 (December 2016): 123106. http://dx.doi.org/10.1088/1674-1137/40/12/123106.

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20

Jena, S. N., and M. R. Behera. "Electromagnetic Form Factors and Static Properties of the Nucleons in a Chiral Symmetric Quark Model." International Journal of Modern Physics E 07, no. 01 (February 1998): 69–88. http://dx.doi.org/10.1142/s0218301398000038.

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Nucleon charge and magnetic form factors [Formula: see text] are computed in an independent-quark model with an equally mixed scalar and vector confining potential in square root form taking into account the corrections due to center-of-mass motion and pion-clound effects. The values obtained for the nucleon static properties such as the magnetic moment, charge radius and axial vector coupling constant in the neutron beta decay process agree reasonably with the corresponding experimental data. The pseudo-scalar and pseudo-vector pion-nucleon coupling constants are found to be gNNπ=13.43 and fNNπ=0.282, which are in excellent agreement with the experimental data.

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21

SAHU, SARIRA, and S. C. PHATAK. "NUCLEON PROPERTIES IN CHIRAL COLOR DIELECTRIC MODEL." Modern Physics Letters A 07, no. 08 (March 14, 1992): 709–21. http://dx.doi.org/10.1142/s0217732392000689.

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The chiral extension of color dielectric model has been used to study the static properties of nucleon. In this calculation we have treated the gluon and the pion fields perturbatively. It is found that the neutron charge rms radius and the pion-nucleon coupling constant are almost insensitive to the parameters used and are in excellent agreement with the experimental values. For better fitting the proton charge rms radius, nucleon magnetic moments and axial coupling constant prefer large quark masses (~100 MeV) and small glueball masses (<1100 MeV). The strong coupling constant is found to be very sensitive to the quark and glueball masses.

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22

Bär, Oliver. "Chiral perturbation theory and nucleon–pion-state contaminations in lattice QCD." International Journal of Modern Physics A 32, no. 15 (May 30, 2017): 1730011. http://dx.doi.org/10.1142/s0217751x17300113.

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Multiparticle states with additional pions are expected to be a non-negligible source of excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory can be employed to calculate the contamination due to two-particle nucleon–pion-states in various nucleon observables. Leading order results are presented for the nucleon axial, tensor and scalar charge and three Mellin moments of parton distribution functions (quark momentum fraction, helicity and transversity moment). Taking into account phenomenological results for the charges and moments the impact of the nucleon–pion-states on lattice estimates for these observables can be estimated. The nucleon–pion-state contribution results in an overestimation of all charges and moments obtained with the plateau method. The overestimation is at the 5–10% level for source-sink separations of about 2 fm. The source-sink separations accessible in contemporary lattice simulations are found to be too small for chiral perturbation theory to be directly applicable.

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23

Djukanovic, Dalibor, Tim Harris, Georg M. von Hippel, Parikshit M. Junnarkar, Harvey B. Meyer, and Hartmut Wittig. "Electromagnetic form factors and axial charge of the nucleon from Nf = 2 + 1 Wilson fermions." EPJ Web of Conferences 175 (2018): 06013. http://dx.doi.org/10.1051/epjconf/201817506013.

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We present an update on our determination of the electromagnetic form factors and axial charge of the nucleon from the Nf = 2 + 1 CLS ensembles with increased statistics and an additional finer lattice spacing. We also investigate the impact of O(a)-improvement of the currents.

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24

Bär, Oliver. "Multi-hadron-state contamination in nucleon observables from chiral perturbation theory." EPJ Web of Conferences 175 (2018): 01007. http://dx.doi.org/10.1051/epjconf/201817501007.

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Multi-particle states with additional pions are expected to be a non-negligible source of the excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory (ChPT) can be employed to calculate the contamination due to two-particle nucleon-pion states in various nucleon observables. Results to leading order are presented for the nucleon axial, tensor and scalar charge and three Mellin moments of parton distribution functions: the average quark momentum fraction, the helicity and the transversity moment. Taking into account experimental and phenomenological results for the charges and moments the impact of the nucleon-pionstates on lattice estimates for these observables can be estimated. The nucleon-pion-state contribution leads to an overestimation of all charges and moments obtained with the plateau method. The overestimation is at the 5-10% level for source-sink separations of about 2 fm. Existing lattice data is not in conflict with the ChPT predictions, but the comparison suggests that significantly larger source-sink separations are needed to compute the charges and moments with few-percent precision.

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25

Ali Khan, A., M. Göckeler, Ph Hägler, T. R. Hemmert, R. Horsley, A. C. Irving, D. Pleiter, et al. "The axial charge of the nucleon: lattice results compared with chiral perturbation theory." Nuclear Physics B - Proceedings Supplements 153, no. 1 (March 2006): 128–34. http://dx.doi.org/10.1016/j.nuclphysbps.2006.01.019.

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26

Altmeyer, R., M. Göckeler, R. Horsley, E. Laermann, and G. Schierholz. "Axial baryonic charge and the spin content of the nucleon: A lattice investigation." Physical Review D 49, no. 7 (April 1, 1994): R3087—R3090. http://dx.doi.org/10.1103/physrevd.49.r3087.

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27

Minamisono, K., K. Matsuta, T. Minamisono, T. Yamaguchi, T. Sumikama, T. Nagatomo, M. Ogura, et al. "Spin Manipulation by Use of Nuclear Quadrupole Interactions – Quarks and Medium Effects in the Nucleus." Zeitschrift für Naturforschung A 57, no. 6-7 (July 1, 2002): 557–60. http://dx.doi.org/10.1515/zna-2002-6-748.

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The alignment correlation terms in the β-ray angular distributions from the purely spin aligned mirror pair 12B(Iπ= 1+ T1/2 = 20.2ms) and 12N(Iπ = 1+,T1/2 = 11.0ms)were precisely measured to place a new limit on the G-parity conservation law. For the creation of the alignment, the spin manipulation technique was applied, which utilized the nuclear quadrupole interactions. The - parity violating induced tensor coefficient was determined to be 2MfT/fa = -0,15 ± 0,12 ± 0,05 (theor.), which is consistent with the theoretical prediction based on QCD in which 2MfT/fA is proportional to the mass difference between up and down quarks which constitute the nucleon. Also determined the axial charge to be y= 4,90±0,10 (90% CL). From the result, we have found that the nucleon mass inside the nucleus is reduced (16 4)% relative to the free nucleon mass

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28

Zahed, Ismail. "Spin Sum Rule of the Nucleon in the QCD Instanton Vacuum." Symmetry 14, no. 5 (May 4, 2022): 932. http://dx.doi.org/10.3390/sym14050932.

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We briefly review some essential aspects of the QCD instanton vacuum in relation to the quantum breaking of conformal symmetry, the spontaneous breaking of chiral symmetry, and the axial U(1) anomaly. The anomaly causes the intrinsic nucleon spin to transmute to the vacuum topological charge by quantum tunneling. We use Ji′s invariant spin decomposition to discuss the spin budget of the nucleon as a quark–diquark state in the QCD instanton vacuum. A measure of the intrinsic quark spin of the nucleon is a measure of the quenched topological susceptibility of the QCD instanton vacuum.

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29

Hansen, Maxwell T., and Harvey B. Meyer. "On the effect of excited states in lattice calculations of the nucleon axial charge." Nuclear Physics B 923 (October 2017): 558–87. http://dx.doi.org/10.1016/j.nuclphysb.2017.08.017.

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30

WITTIG, HARTMUT. "LOW-ENERGY QCD II — STATUS OF LATTICE CALCULATIONS." Modern Physics Letters A 28, no. 25 (August 14, 2013): 1360013. http://dx.doi.org/10.1142/s0217732313600134.

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The current status of lattice calculations is reviewed, with a particular emphasis on the question whether lattice simulations have matured to a stage where there is full interaction with experiment. Particular examples include the hadron spectrum, mesonic form factors and decay constants, the axial charge of the nucleon, and the hadronic vacuum polarization contribution to the muon (g-2).

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31

JENA, S. N., and S. PANDA. "A QUARK-MODEL FIT FOR THE ELECTROMAGNETIC PROPERTIES OF OCTET BARYONS." International Journal of Modern Physics A 07, no. 12 (May 10, 1992): 2841–61. http://dx.doi.org/10.1142/s0217751x92001289.

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A simple independent-quark model based on the Dirac equation with an equally mixed scalar–vector linear confining potential model is used to obtain a fit for the electromagnetic properties — like the magnetic moments, charge radii and axial-vector coupling-constant ratios — of octet baryons, taking into account the appropriate center-of-mass corrections. This fit is extended to include the quark-core contributions to the nucleon electromagnetic form factors [Formula: see text], [Formula: see text], [Formula: see text] and the axial-vector form factor GA(q2). The respective root-mean-square radii associated with [Formula: see text] and GA(q2) come out as [Formula: see text] and [Formula: see text]. The possibility of restoring in this model the chiral symmetry in the usual way is discussed and the pion-nucleon coupling constant is found as gπ NN = 13.72 as compared to (gπ NN ) exp ≃ 13.

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32

Sasaki, Shoichi, Tom Blum, Shigemi Ohta, and Kostas Orginos. "Nucleon axial charge from quenched lattice QCD with domain wall fermions and improved gauge action." Nuclear Physics B - Proceedings Supplements 106-107 (March 2002): 302–4. http://dx.doi.org/10.1016/s0920-5632(01)01695-4.

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33

Ohta, Shigemi. "Nucleon axial charge from quenched lattice QCD with domain wall fermions and DBW2 gauge action." Nuclear Physics B - Proceedings Supplements 119 (May 2003): 389–91. http://dx.doi.org/10.1016/s0920-5632(03)01563-9.

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34

MCKEOWN, R. D. "THE NUCLEON'S MIRROR IMAGE: REVEALING THE STRANGE AND UNEXPECTED." Modern Physics Letters A 18, no. 02n06 (February 28, 2003): 75–84. http://dx.doi.org/10.1142/s0217732303010016.

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An extensive program of parity-violating electron scattering experiments is providing new insight into the structure of the nucleon. Measurement of the vector form factors enables a definitive study of potential strange quark-antiquark contributions to the nucleon's electromagnetic structure, including the magnetic moment and charge distribution. Recent experimental results have already indicated that effects of strangeness are much smaller than theoretically expected. In addition, the neutral axial form factor appears to display substantial corrections as one might expect from an anapole effect.

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35

STROBEL, GEORGE L. "BARYON MAGNETIC MOMENTS AND SPIN DEPENDENT QUARK FORCES." International Journal of Modern Physics E 11, no. 01 (February 2002): 71–81. http://dx.doi.org/10.1142/s0218301302000697.

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The J=3/2 Δ, J=1/2 nucleon mass difference shows that quark energies can be spin dependent. It is natural to expect that quark wave functions also depend on spin. In the octet, such spin dependent forces lead to different wave functions for quarks with spin parallel or antiparallel to the nucleon spin. A two component Dirac equation wave function is used for the quarks assuming small current quark masses for the u and d quarks. Then, the neutron/proton magnetic moment ratio, the nucleon axial charge, and the spin content of the nucleon can all be simultaneously fit assuming isospin invariance between the u and d quarks, but allowing for spin dependent forces. The breakdown of the Coleman–Glashow sum rule for octet magnetic moments follows naturally in this Dirac approach as the bound quark energy also effects the magnetic moment. Empirically the bound quark energy increases with the number of strange quarks in the system. Allowing the strange quark wave function similar spin dependence predicts the magnetic moments of the octet, in close agreement with experiment. Differences between the octet and decuplet magnetic moments are also explained immediately with spin dependent wave functions.

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36

Ball, Richard D., Stefano Forte, and Giovanni Ridolfi. "Next-to-leading order determination of the singlet axial charge and the polarized gluon content of the nucleon." Physics Letters B 378, no. 1-4 (June 1996): 255–66. http://dx.doi.org/10.1016/0370-2693(96)00376-0.

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Buchmann, Alfons J. "Exchange Currents in Baryons." Zeitschrift für Naturforschung A 52, no. 12 (December 1, 1997): 877–940. http://dx.doi.org/10.1515/zna-1997-1208.

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This paper reviews calculations of the electromagnetic properties of baryons using the constituent quark model. We start with a short discussion of spontaneous chiral symmetry breaking, which is essential in understanding the transition from QCD to the constituent quark model. We then discuss a chiral version of the constituent quark model, which simulates the symmetries and dynamical content of the underlying field theory in terms of gluon, pion and sigma exchange between constituent quarks. We show that the electromagnetic current charge and current operators, usually approximated by one-body operators (impulse approximation), must be supplemented by appropriate two-body terms (exchange currents). The latter represent the gluon and pion exchange degrees of freedom in the electromagnetic current operator. These exchange currents must be included for reasons of completeness and consistency. Most importantly, however, they are needed in order for the electromagnetic current to be conserved. We also study the effect of scalar exchange currents connected with the confinement and sigma exchange potentials. By including these twobody exchange currents we go beyond the single-quark impulse approximation, which has mainly been used up to now. The inclusion of gluon- pion-, and scalar-exchange currents in the quark potential model is the new point of the present work. We show that for some observables, such as the magnetic moments, charge, and magnetic radii of the proton and charged Δ (1232) states, exchange currents contribute at the level of some 10%. The same holds true for the magnetic moments of the entire baryon octet, with the exception of the Ξ- magnetic moment. On the other hand, the neutron charge radius, the quadrupole moments of the Δ, and the N → Δ transition quadrupole moment, are dominated by pion and gluon exchange contributions to the charge density operator. The inclusion of the pion and gluon exchange currents leads to a neutron charge radius of the correct size and sign. Based on the gluon and pion exchange current diagrams, we derive parameter-free relations between the neutron charge radius, the quadrupole moment of the Δ, and the N → Δ transition quadrupole moment. Neglecting configuration mixing, we find that the neutron charge radius and the N → Δ transition quadrupole moment are simply related as QN→Δ = r2n√2. The implications of Siegert's theorem for the calculation of the E2 form factor in the N → Δ transition are studied. Finally, we discuss the axial coupling constant of the nucleon. We show that the inclusion of axial pair exchange currents does not significantly alter the NRQM prediction.

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Syromyatnikov, A. G. "The g – 2 muon anomaly in di-muon production with the torsion in LHC." International Journal of Geometric Methods in Modern Physics 13, no. 07 (July 25, 2016): 1650093. http://dx.doi.org/10.1142/s0219887816500936.

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It was considered within the framework of the conformal gauge gravitational theory CGTG coupling of the standard model fermions to the axial torsion and preliminary discusses the impact of extra dimensions, in particular, in a five-dimensional space-time with Randall–Sundrum metric, where the fifth dimension is compactified on an [Formula: see text] orbifold, which as it turns out is conformally to the fifth dimension flat Euclidean space with permanent trace of torsion, with a compactification radius [Formula: see text] in terms of the radius of a CGTG gravitational screening, through torsion in a process [Formula: see text] and LHC data. In general, have come to the correct set of the conformal calibration curvature the Faddeev–Popov diagram technique type, that follows directly from dynamics. This leads to the effect of restrictions on neutral spin currents of gauge fields by helicity and the Regge’s form theory. The diagrams reveals the fact of opening of the fine spacetime structure in a process [Formula: see text] with a center-of-mass energy of 14[Formula: see text]TeV, indicated by dotted lines and texture columns, as a result of p–p collision on [Formula: see text][Formula: see text]cm scales from geometric shell gauge bosons of the SM continued by the heavy axial torsion resonance, and even by emerging from the inside into the outside of the ultra-light (freely-frozen in muon’s spin) axial torsion. We then evaluate the contribution of the torsion to the muon anomaly to derive new constraints on the torsion parameters. It was obtained that on the [Formula: see text] scattering through the exchange of axial torsion accounting, the nucleon anomalous magnetic moment in the eikonal phase leads to additive additives which is responsible for the spin-flip in the scattering process, the scattering amplitude is classical and characterized by a strong the torsion coupling [Formula: see text]. So the scattering of particles, occurs as on the Coulomb center with the charge [Formula: see text] This is the base model which is the g[Formula: see text]2 muon anomaly. The muon anomaly contribution due to the heavy axial vector torsion arises from coupling the muon with torsion as external field. This leads to negative energy additive to mass of muons which makes the missing part of the g[Formula: see text]2 muon anomaly. It takes place at reasonable values of the transverse front size of the exact solution CGTG equations types of torsion waves with the spin-flip close to the size of the Compton length muon.

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39

Akbar, F., M. Rafi Alam, M. Sajjad Athar, S. Chauhan, S. K. Singh, and F. Zaidi. "Electron and Muon production cross-sections in quasielastic ν(ν̄)-Nucleus scattering for Eν < 1GeV." International Journal of Modern Physics E 24, no. 11 (November 2015): 1550079. http://dx.doi.org/10.1142/s0218301315500792.

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In this paper, we have studied (anti)neutrino induced charged current quasielastic (CCQE) scattering from some nuclear targets in the energy region of [Formula: see text]. Our aim is to confront electron and muon production cross-sections relevant for [Formula: see text] or [Formula: see text] oscillation experiments. The effects due to lepton mass and its kinematic implications, radiative corrections, second class currents (SCCs) and uncertainties in the axial and pseudoscalar form factors are calculated for (anti)neutrino induced reaction cross-sections on free nucleon as well as the nucleons bound in a nucleus where nuclear medium effects influence the cross-section. For the nuclear medium effects, we have taken some versions of Fermi gas model (FGM) available in the literature. The results for (anti)neutrino–nucleus scattering cross-section per interacting nucleons are compared with the corresponding results in free nucleon case.

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Minanisono, K., T. Yamaguchi, K. Matsuta, T. Minamisono, T. Ikeda, Y. Muramoto, M. Fukuda, et al. "New limit of the G-parity irregular induced tensor current and of the axial charge in the weak nucleon current detected in alignment correlation terms of 12B and 12N β decays." Nuclear Physics A 654, no. 1 (July 1999): 955c—960c. http://dx.doi.org/10.1016/s0375-9474(00)88580-2.

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Martyanov, Dmitry, Efrem Soukhovitskiĩ, Roberto Capote, José M. Quesada, and Satoshi Chiba. "Multiband coupling and nuclear softness in optical model calculations for even-even and odd-A actinides." EPJ Web of Conferences 239 (2020): 03003. http://dx.doi.org/10.1051/epjconf/202023903003.

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A new dispersive multiband coupled channels optical model with soft-rotator “effective” deformations is proposed to describe nucleon scattering on even-even and odd-A actinides. The impact of the introduction of axial and non-axial dynamical deformations that describe nuclear softness is discussed. Softness and multiband coupling are shown to change compound-nucleus formation cross section by up to ≈ 10% for incident neutron energies below 1 MeV.

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Bernard, Véronique, Norbert Kaiser, and Ulf-G. Meißner. "Axial charges and form factors of the nucleon." Physics Letters B 237, no. 3-4 (March 1990): 545–50. http://dx.doi.org/10.1016/0370-2693(90)91222-w.

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Choi, K. S., W. Plessas, and R. F. Wagenbrunn. "Quark-Model Predictions for Axial Charges of Nucleon andN* Resonances." EPJ Web of Conferences 3 (2010): 03008. http://dx.doi.org/10.1051/epjconf/20100303008.

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Nyman, Ebbe M., and D. O. Riska. "Nuclear pion absorption and the axial exchange-charge operator." Physics Letters B 215, no. 1 (December 1988): 29–32. http://dx.doi.org/10.1016/0370-2693(88)91063-5.

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Tegen, R. "On the axial charge gA and the quark confinement in nucleons." Physics Letters B 172, no. 2 (May 1986): 153–55. http://dx.doi.org/10.1016/0370-2693(86)90826-9.

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Kuramashi, Yoshinobu. "Nucleon spin structures from lattice QCD: Flavor singlet axial and tensor charges." Nuclear Physics A 629, no. 1-2 (February 1998): 235–44. http://dx.doi.org/10.1016/s0375-9474(97)00693-3.

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Lapierre, A. "Time-dependent potential functions to stretch the time distributions of ion pulses ejected from EBIST." Canadian Journal of Physics 95, no. 4 (April 2017): 361–69. http://dx.doi.org/10.1139/cjp-2016-0716.

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Electron beam ion sources and traps (EBIST) produce and trap highly charged atomic ions with an electron beam of high current density. The ions are confined in the radial space-charge potential of the electron beam and a long square-shaped axial electrostatic potential well. An important field of application of EBIST is charge breeding of highly charged ions at radioactive ion beam facilities. There, highly charged radioactive isotopes are accelerated by particle accelerators for experiments in nuclear astrophysics and to study the structure of unstable nuclei. The width in time of the ion pulses ejected from EBIST can often contain too many ions for nuclear physics detection systems to efficiently detect all single radioactive isotopes or related events. Neglecting the influence of ion–ion collisions on the extraction rate, this publication derives, for different initial thermal energy distributions of the trapped ions, the time-dependent trap-opening functions to stretch the time distribution of ion pulses ejected from an EBIST trapping potential for the release of ions at a constant rate over an extended extraction period.

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Ejiri, H. "Nuclear Spin Responses for Neutrinos in Astroparticle Physics." International Journal of Modern Physics E 06, no. 01 (March 1997): 1–43. http://dx.doi.org/10.1142/s0218301397000020.

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Nuclear spin responses are of vital importance for studies of neutrinos, weakly interacting particles and of weak interactions in nuclei. The physics objectives are concerned with lepton nuclear physics within and beyond the standard theory. Here nuclei, which consist of elementary particles in good quantum (eigen) states, are used as excellent micro-laboratories for studying fundamental particles and interactions. Subjects discussed include neutrinos(ν) and weak interactions, weakly interacting massive particles as candidates for dark matters (DM), and other related problems. Experimental studies of them are made by investigating ultra rare nuclear processes at low background underground laboratories. Nuclear responses relevant to electroweak processes, neutrinos, and weakly interacting massive particles are discussed. Nuclear spin isospin responses associated with axial charged weak currents are investigated by using charge-exchange spin flip nuclear reactions at the RCNP ring cyclotron laboratory.

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Bodmann, B. A., N. E. Booth, G. Drexlin, V. Eberhard, J. A. Edgington, K. Eitel, M. Ferstl, et al. "Determination of the nuclear weak axial charge radius of via the reaction." Physics Letters B 339, no. 3 (November 1994): 215–18. http://dx.doi.org/10.1016/0370-2693(94)90634-3.

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Towner, I. S. "Meson-Exchange Currents in Time-Like Axial-Charge Transitions." Annual Review of Nuclear and Particle Science 36, no. 1 (December 1986): 115–36. http://dx.doi.org/10.1146/annurev.ns.36.120186.000555.

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Journal articles on the topic 'Nucleon axial charge'

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