Wed·Jan 23, 2019Wednesday·January 23, 2019

1. 01*

   Nuclear coalescence from correlation functions

   Kfir Blum🇮🇱 · Masahiro Takimoto🇮🇱

   We derive a simple formula relating the cross section for light cluster production (defined via a coalescence factor) to the two-proton correlation function measured in heavy-ion collisions. The formula generalises earlier coalescence-correlation relations found by Scheibl & Heinz and by Mrowczynski for Gaussian source models. It motivates joint experimental analyses of Hanbury Brown-Twiss (HBT) and cluster yield measurements in existing and future data sets.

   ↳ nucl-thhep-phnucl-exPRC(2019)·71 citations
2. 02*

   Orbital Angular Momentum at Small $x$

   Yuri V. Kovchegov🇺🇸

   We determine the small Bjorken $x$ asymptotics of the quark and gluon orbital angular momentum (OAM) distributions in the proton in the double-logarithmic approximation (DLA), which resums powers of ${\alpha }_s{\ln }^2(1/x)$ with ${\alpha }_s$ the strong coupling constant. Starting with the operator definitions for the quark and gluon OAM, we simplify them at small $x$, relating them, respectively, to the polarized dipole amplitudes for the quark and gluon helicities defined in our earlier works. Using the small-$x$ evolution equations derived for these polarized dipole amplitudes earlier we arrive at the following small-$x$ asymptotics of the quark and gluon OAM distributions in the large-$N_c$ limit: \begin{align} L_{q + \bar{q}} (x, Q^2) = - \Delta \Sigma (x, Q^2) \sim \left(\frac{1}{x}\right)^{\frac{4}{\sqrt{3}} \, \sqrt{\frac{\alpha_s \, N_c}{2 \pi}} }, \ \ \ \ \ L_G (x, Q^2) \sim \Delta G (x, Q^2) \sim \left(\frac{1}{x}\right)^{\frac{13}{4 \sqrt{3}} \, \sqrt{\frac{\alpha_s \, N_c}{2 \pi}}} . \end{align}

   ↳ hep-phnucl-exnucl-thJHEP(2019)·61 citations
3. 03*

   Degeneracy in Studying the Supranuclear Equation of State and Modified Gravity with Neutron Stars

   Lijing Shao🇨🇳

   It is generally acknowledged that an extrapolation in physics from a well-known scale to an unknown scale is perilous. This prevents us from using laboratory experience to gain precise information for the supranuclear matter inside neutron stars (NSs). With operating and upcoming astronomical facilities, NSs' equation of state (EOS) is expected to be determined at a new level in the near future, under the assumption that general relativity (GR) is the correct theory for gravitation. While GR is a reasonable working assumption yet still an extrapolation, there could be a large uncertainty due to the not-so-well-tested strong gravitational field inside NSs. Here we review some recent theoretical efforts towards a better understanding of the degeneracy between the supranuclear EOS and alternative gravity theories.

   ↳ gr-qcastro-ph.HEnucl-exnucl-thAIP Conf.Proc.(2019)·33 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.