Mon·Oct 29, 2018Monday·October 29, 2018

1. 01*

   Reliability of Taylor expansions in QCD

   Bastian B. Brandt🇩🇪 · Gergely Endrodi🇩🇪

   We investigate the reliability of the Taylor expansion method in QCD with isospin chemical potentials using lattice simulations. By comparing the expansion of the number density to direct results, the range of validity of the leading- and next-to-leading order expansions is determined. We also elaborate on the convergence properties of the Taylor series by comparing the leading estimate for the radius of convergence to the position of the nearest singularity, i.e. the onset of pion condensation. Our results provide a handle for quantifying the uncertainties of Taylor expansions in baryon chemical potentials.

   ↳ hep-lathep-phnucl-exnucl-thPRD(2019)·46 citations
2. 02*

   Studies of beauty suppression via nonprompt D${}^0$ mesons in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV

   CMS Collaboration

   The transverse momentum spectra of D${}^0$ mesons from b hadron decays are measured at midrapidity ($|y|$ $<$ $1$) in pp and PbPb collisions at a nucleon-nucleon center of mass energy of 5.02 TeV with the CMS detector at the LHC. The D${}^0$ mesons from b hadron decays are distinguished from prompt D${}^0$ mesons by their decay topologies. In PbPb collisions, the B $\to$ D${}^0$ yield is found to be suppressed in the measured $p_{\mathrm{T}}$ range from 2 to 100 GeV$/c$ as compared to pp collisions. The suppression is weaker than that of prompt D${}^0$ mesons and charged hadrons for $p_{\mathrm{T}}$ around 10 GeV$/c$. While theoretical calculations incorporating partonic energy loss in the quark-gluon plasma can successfully describe the measured B $\to$ D${}^0$ suppression at higher $p_{\mathrm{T}}$, the data show an indication of larger suppression than the model predictions in the range of 2 $<$ $p_{\mathrm{T}}$ $<$ 5 GeV$/c$.

   ↳ hep-exnucl-exPRL(2019)·87 citations
3. 03*

   Empirical pairing gaps and neutron-proton correlations

   B.S. Ishkhanov🇷🇺 · S. Sidorov · T. Tretyakova · E. Vladimirova

   Analysis of various mass relations connected with neutron-proton correlations in atomic nuclei is carried out. On the example of $N=Z$ chain it is shown that for self-adjoint nuclei various formulas proposed in literature for $np$ pairing energy estimations lead to similar results. Significant differences between the calculation methods arise when nuclei with $N\ne Z$ are considered, which allows to show the complexity of neutron-proton correlations in different types of atomic nuclei and to make some assumptions on the correspondence of a mass ratio to the real effect of $np$ pairing. The Shell Model parametrization of binding energy makes it possible to arrive to additional conclusions on the structure of mass formulas and their interrelationships with one another.

   ↳ nucl-thnucl-exCPC(2019)·8 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.