Nuclear Theory·nucl-th

Wednesday·April 12, 2017

9 papers—6 primary·3 cross-listed

07
3-D Glasma initial state from small-x evolution
Björn Schenke🇺🇸 · Sören Schlichting🇺🇸
We present an ab-initio approach to compute the longitudinal dependence of the initial state in heavy-ion collisions by including small-x evolution of the nuclear gluon distributions. Extending the IP-Glasma model by including JIMWLK rapidity evolution, we compute event-by-event rapidity distributions of produced gluons and the early time energy momentum tensor as a function of space-time rapidity and transverse coordinates. We show how the effects of small-x evolution manifest themselves in longitudinal (rapidity) correlations of event-by-event multiplicities and transverse geometry and compare our results to various phenomenological models and experimental observations.
↳ hep-phnucl-thNPA(2017)·1 citation
08
Precise measurement of alpha_K and alpha_T for the 109.3-keV M4 transition in 125Te: Test of internal-conversion theory
N. Nica · J.C. Hardy · V.E. Iacob · T.A. Werke · C.M. Folden III · K. Ofodile · M.B. Trzhaskovskaya
We have measured the K-shell and total internal conversion coefficients (ICCs), alpha_K and alpha_T, for the 109.3-keV M4 transition in 125Te to be 185.0(40) and 350.0(38), respectively. Previously this transition's ICCs were considered anomalous, with alpha values lying below calculated values. When compared with Dirac-Fock calculations, our new results show good agreement. The alpha_K result agrees well with the version of the theory that takes account of the K-shell atomic vacancy and disagrees with the one that does not. This is consistent with our conclusion drawn from a series of high multipolarity transitions.
↳ nucl-exnucl-thPRC(2017)·4 citations
09
Pion radiative weak decay from the instanton vacuum
Sang-In Shim🇰🇷 · Hyun-Chul Kim🇰🇷
We investigate the vector and axial-vector form factors for the pion radiative weak decays $π^{+} \to e^{+} ν_{e} γ$ and $π^{+} \to e^{+} ν_{e} e^{+} e^{-}$ , based on the gauged effective chiral action from the instanton vacuum in the large $N_{c}$ limit. The nonlocal contributions, which arise from the gauging of the action, enhance the vector form factor by about $20 %$ , whereas the axial-vector form factor is reduced by almost $30 %$ . Both the results for the vector and axial-vector form factors at the zero momentum transfer are in good agreement with the experimental data. The dependence of the form factors on the momentum transfer is also studied. The slope parameters are computed and compared with other works.
↳ hep-phhep-exnucl-thPLB(2017)·5 citations

Affiliations

first authorsco-authorsvia INSPIRE

3-D Glasma initial state from small-x evolution

Precise measurement of alpha_K and alpha_T for the 109.3-keV M4 transition in 125Te: Test of internal-conversion theory

Pion radiative weak decay from the instanton vacuum

Affiliations