scholarly journals Electromagnetic and axial current form factors and spectroscopy of three-flavor holographic baryons

2019 ◽  
Vol 99 (5) ◽  
Author(s):  
Ori C. Druks ◽  
Pak Hang Chris Lau ◽  
Ismail Zahed
1974 ◽  
Vol 234 (2) ◽  
pp. 445-457 ◽  
Author(s):  
Kohichi Ohta ◽  
Masashi Wakamatsu

1976 ◽  
Vol 55 (1) ◽  
pp. 229-242
Author(s):  
H. Kamo ◽  
A. Niegawa

2021 ◽  
Vol 815 ◽  
pp. 136150
Author(s):  
Chen Chen ◽  
Christian S. Fischer ◽  
Craig D. Roberts ◽  
Jorge Segovia
Keyword(s):  

Author(s):  
Dandan Shen ◽  
Huimin Ren ◽  
Fan Wu ◽  
Ruilin Zhu

We present a next-to-leading order (NLO) relativistic correction to [Formula: see text] tensor form factors within nonrelativistic QCD (NRQCD). We also consider complete Dirac bilinears [Formula: see text] with [Formula: see text] matrices [Formula: see text] in the [Formula: see text] transition. The relation among different current form factors is given and it shows that symmetries emerge in the heavy bottom quark limit. For a phenomenological extension, we propose to extract the long-distance matrix elements (LDMEs) for [Formula: see text] meson from the recent HPQCD lattice data and the NLO form factors at large momentum recoil.


2005 ◽  
Vol 20 (08n09) ◽  
pp. 1785-1790 ◽  
Author(s):  
D. O. RISKA

The chiral quark model posits that pions couple to the axial current of constituent quarks. This chiral pion coupling governs the pion decays of baryon resonances and also implies pion and multipion interactions between the quarks. The qualitative features of this model for the description of pionic decay widths and baryon spectra are outlined. When the covariant quark model wave function for the nucleon is chosen so as to describe the empirical nucleon form factors the pion decay widths of the positive parity resonances are underpredicted. This indicates the presence of significant multiquark components in these resonances.


2018 ◽  
Vol 175 ◽  
pp. 06012 ◽  
Author(s):  
Shigemi Ohta

Nucleon-structure calculations of isovector vector-and axialvector-current form factors, transversity and scalar charge, and quark momentum and helicity fractions are reported from two recent 2+1-flavor dynamical domain-wall fermions lattice-QCD ensembles generated jointly by the RIKEN-BNL-Columbia and UKQCD Collaborations with Iwasaki × dislocation-suppressing-determinatn-ratio gauge action at inverse lattice spacing of 1.378(7) GeV and pion mass values of 249.4(3) and 172.3(3) MeV.


2019 ◽  
Vol 34 (02) ◽  
pp. 1950009 ◽  
Author(s):  
S. Capitani ◽  
M. Della Morte ◽  
D. Djukanovic ◽  
G. M. von Hippel ◽  
J. Hua ◽  
...  

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.


1976 ◽  
Vol 55 (4) ◽  
pp. 1333b-1333b
Author(s):  
Hideki Kamo ◽  
Akira Niégawa

Author(s):  
Ioan Sauciuc ◽  
Hakan Erturk ◽  
Gregory Chrysler ◽  
Vikram Bala ◽  
Ravi Mahajan

Over the past few years, the air cooling technology improvements present diminishing returns for microprocessors cooling applications. Presently most of the proposed future cooling technologies (i.e. pumped liquid cooling or vapor compressor refrigeration) may need some fluid moving device and a large remote heat exchanger which requires additional volume. Due to the complexity, reliability issues and space requirements it is preferred to extend the air cooling within the current form factors and using passive devices. This paper will show that optimized thermoelectric modules combined with two-phase (liquid/vapor) passive devices can further improve the cooling capability compared to conventional air cooling technologies at reasonable thermoelectric cooler (TEC) power consumption. Current computational fluid dynamics programs are not yet well equipped to find out the most optimized TEC geometry (for a given COP and given thermal requirements) in a reasonable amount of computation time. Therefore, two modeling steps are proposed: find out the preliminary TEC geometry using an ID analytical program (based on uniform heat flux and a given COP) and use it as an input to CFD programs (i.e. Icepak®) for detailed predictions. Using this model, we confirmed that the conventional TEC technology must use some spreading device to dissipate the CPU heat to the TEC cold side. Different spreading devices are considered: solid metal, heat pipe, vapor chambers and single/two phase pumped cooling. Their individual performance integrated with TEC will be presented. In addition, we propose that the TEC performance to be controlled as a function of instantaneous CPU power consumption, ambient temperature and other parameters. This controller offers extra flexibility which can be used for either noise reduction or TEC power reduction. However, such power cycling of the TEC may affect the TEC reliability. Power cycling accelerated test data (>500,000 accelerated cycles) have been performed together with the life predictions will be presented in the paper.


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