Wed·Jun 3, 2015Wednesday·June 3, 2015

1. 01*

   An examination of proton charge radius extractions from e-p scattering data

   John Arrington🇺🇸

   A detailed examination of issues associated with proton radius extractions from elastic electron-proton scattering experiments is presented. Sources of systematic uncertainty and model dependence in the extractions are discussed, with an emphasis on how these may impact the proton charge and magnetic radii. A comparison of recent Mainz data to previous world data is presented, highlighting the difference in treatment of systematic uncertainties as well as tension between different data sets. We find several issues that suggest that larger uncertainties than previously quoted may be appropriate, but do not find any corrections which would resolve the proton radius puzzle.

   nucl-exJ.Phys.Chem.Ref.Data(2015)·19 citations
2. 02*

   Nuclear excitation functions from 40-200 MeV proton irradiation of terbium

   Jonathan W. Engle🇺🇸 · Stepan G. Mashnik🇺🇸 · Lauren A. Parker · Kevin R. Jackman🇺🇸 · Leo J. Bitteker🇺🇸 · John L. Ullmann🇺🇸 · Mark S. Gulley🇺🇸 · Chandra Pillai🇺🇸 · Kevin D. John · Eva R. Birnbaum🇺🇸 · Francois M. Nortier🇺🇸

   Nuclear formation cross sections are reported for 26 radionuclides, measured with 40 to 200 MeV proton irradiations of terbium foils. These data are relevant to the production of medically relevant radionuclides (e.g., 152Tb, 155Tb, 155Eu, and 156Eu) and to ongoing efforts to characterize stellar nucleosynthesis routes passing through long-lived intermediaries (e.g., 153Gd). Computational predictions from the ALICE2011, CEM03.03, Bertini, and INCL+ABLA codes are compared with newly measured data to contribute to the ongoing process of code development, and yields are calculated for selected radionuclides using measured data.

   nucl-exNucl.Instrum.Meth.B(2016)·4 citations
3. 03*

   Real time evolution of non-Gaussian cumulants in the QCD critical regime

   Swagato Mukherjee🇺🇸 · Raju Venugopalan🇺🇸 · Yi Yin🇺🇸

   We derive a coupled set of equations that describe the non-equilibrium evolution of cumulants of critical fluctuations for space-time trajectories on the cross-over side of the QCD phase diagram. In particular, novel expressions are obtained for the non-equilibrium evolution of non-Gaussian Skewness and Kurtosis cumulants. Utilizing a simple model of the space-time evolution of a heavy- ion collision, we demonstrate that, depending on the relaxation rate of critical fluctuations, Skewness and Kurtosis can differ significantly in magnitude as well as in sign from equilibrium expectations. Memory effects are important and shown to persist even for trajectories that skirt the edge of the critical regime. We use phenomenologically motivated parameterizations of freeze-out curves, and of the beam energy dependence of the net baryon chemical potential, to explore the implications of our model study for the critical point search in heavy-ion collisions.

   ↳ hep-phnucl-exnucl-thPRC(2015)·170 citations
4. 04*

   Measurement of the EMC Effect in the Deuteron

   K.A. Griffioen🇺🇸 · J. Arrington🇺🇸 · M.E. Christy🇺🇸 · R. Ent🇺🇸 · N. Kalantarians🇺🇸 · C.E. Keppel🇺🇸 · S.E. Kuhn🇺🇸 · W. Melnitchouk🇺🇸 · G. Niculescu🇺🇸 · I. Niculescu🇺🇸 · S. Tkachenko🇺🇸 · J. Zhang🇺🇸

   We have determined the structure function ratio $R_{\mathrm{EMC}}^d=F_2^d/(F_2^n+F_2^p)$ from recently published $F_2^n/F_2^d$ data taken by the BONuS experiment using CLAS at Jefferson Lab. This ratio deviates from unity, with a slope $d{R}_{\mathrm{EMC}}^d/dx=-0.10\pm 0.05$ in the range of Bjorken $x$ from 0.35 to 0.7, for invariant mass $W>1.4$ GeV and $Q^2>1$ GeV${}^2$. The observed EMC effect for these kinematics is consistent with conventional nuclear physics models that include off-shell corrections, as well as with empirical analyses that find the EMC effect proportional to the probability of short-range nucleon-nucleon correlations.

   ↳ hep-phnucl-exPRC(2015)·49 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.