Wed·Dec 30, 2015Wednesday·December 30, 2015

1. 01*

   J/{\psi} and {\Upsilon} measurements via the di-muon channel in Au + Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 200 GeV with the STAR experiment

   Rongrong Ma (STAR Collaboration)🇺🇸

   Measurements of quarkonium production in heavy-ion collisions have played an essential role in understanding the properties of the Quark Gluon Plasma created in such collisions. In early 2014, the Muon Telescope Detector, designed to trigger on and identify muons based on its precise timing information, was fully installed in STAR. It opens the door to measure quarkonia via the di-muon channel for the first time at the STAR experiment, with the potential to separate different {\Upsilon} states. In this talk, we present the measurements of J/{\psi} suppression and elliptic flow at mid-rapidity in Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 200 GeV down to low transverse momentum ($p_{\mathrm{T}}$). The suppression is found to decrease with increasing $p_{\mathrm{T}}$ while the elliptic flow is consistent with 0 for $p_{\mathrm{T}}$ above 2 GeV/c. Furthermore, the measurement of different {\Upsilon} states is explored within the precision of the available statistics.

   nucl-exNPA(2016)·1 citation
2. 02*

   Gravitational Gamma Spectrometer for Studying the Gamma Resonance of the Long-Lived Isomer 103mRh

   A.V. Davydov · Yu.N. Isaev · V.D. Kalantarov · M.M. Korotkov · V.V. Migachev · Yu.B. Novozhilov · A.M. Stepanov🇺🇸

   The principle of operation and the construction are described of the gravitational gamma spectrometer to study the gamma resonance of the long-lived isomer ${}^{103m}$Rh. This is a table-top device which measures the form of gamma resonance by the dependence of counting rate of gamma-rays in collimated beams on the angle of their inclination with respect of the horizontal plane. Methods of fabrication of gamma-sources for this device are considered.

   ↳ physics.ins-detnucl-ex0 citations
3. 03*

   Phenomenological QCD equations of state for neutron stars

   Toru Kojo🇺🇸 · Philip D. Powell🇺🇸 · Yifan Song🇺🇸 · Gordon Baym🇺🇸

   We delineate the properties of QCD matter at baryon density n_B=1-10n_0 (n_0: nuclear saturation density), through the construction of neutron star equations of state that satisfy the neutron star mass-radius constraints as well as physical conditions on the speed of sound. The QCD matter is described in the 3-window modeling: at n_B < 2n_0 purely nuclear matter; at n_B > 5n_0 percolated quark matter; and at 2n_0 < n_B < 5n_0 matter intermediate between these two which are constructed by interpolation. Using a schematic quark model with effective interactions inspired from hadron and nuclear physics, we analyze the strength of interactions necessary to describe observed neutron star properties. Our finding is that the interactions should remain as strong as in the QCD vacuum, indicating that gluons at n_B =1-10 n_0 remain non-perturbative even after quark matter formation.

   ↳ hep-phastro-ph.HEnucl-exnucl-thNPA(2016)·24 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.