Wed·Nov 19, 2014Wednesday·November 19, 2014

1. 01*

   Direct study of the alpha-nucleus optical potential at astrophysical energies using the 64Zn(p,alpha)61Cu reaction

   Gy. Gyürky🇭🇺 · Zs. Fülöp🇭🇺 · Z. Halász🇭🇺 · G.G. Kiss🇭🇺 · T. Szücs🇭🇺

   In the model calculations of heavy element nucleosynthesis processes the nuclear reaction rates are taken from statistical model calculations which utilize various nuclear input parameters. It is found that in the case of reactions involving alpha particles the calculations bear a high uncertainty owing to the largely unknown low energy alpha-nucleus optical potential. Experiments are typically restricted to higher energies and therefore no direct astrophysical consequences can be drawn. In the present work a (p,alpha) reaction is used for the first time to study the alpha-nucleus optical potential. The measured 64Zn(p,alpha)61Cu cross section is uniquely sensitive to the alpha-nucleus potential and the measurement covers the whole astrophysically relevant energy range. By the comparison to model calculations, direct evidence is provided for the incorrectness of global optical potentials used in astrophysical models.

   nucl-exastro-ph.SRnucl-thPRC(2014)·17 citations
2. 02*

   An experimentalist's view of the uncertainties in understanding heavy element synthesis

   W. Loveland🇺🇸

   The overall uncertainties in predicting heavy element synthesis cross sections are examined in terms of the uncertainties associated with the calculations of capture cross sections, fusion probabilities and survival probabilities. Attention is focussed on hot fusion reactions. The predicted heavy element formation cross sections are uncertain to at least one order of magnitude.

   nucl-exnucl-thEPJA(2015)·33 citations
3. 03*

   Thermal Dileptons as Fireball Thermometer and Chronometer

   Ralf Rapp🇺🇸 · Hendrik van Hees🇩🇪

   Thermal dilepton radiation from the hot fireballs created in high-energy heavy-ion collisions provides unique insights into the properties of the produced medium. We first show how the predictions of hadronic many-body theory for a melting $\rho$ meson, coupled with QGP emission utilizing a modern lattice-QCD based equation of state, yield a quantitative description of dilepton spectra in heavy-ion collisions at the SPS and the RHIC beam energy scan program. We utilize these results to systematically extract the excess yields and their invariant-mass spectral slopes to predict the excitation function of fireball lifetimes and (early) temperatures, respectively. We thereby demonstrate that future measurements of these quantities can yield unprecedented information on basic fireball properties. Specifically, our predictions quantify the relation between the measured and maximal fireball temperatures, and the proportionality of excess yields and total lifetime. This information can serve as a "caloric" curve to search for a first-order QCD phase transition, and to detect non-monotonous lifetime variations possibly related to critical phenomena.

   ↳ hep-phnucl-exnucl-thPLB(2016)·194 citations
4. 04*

   Characterization and Performance of Germanium Detectors with sub-keV Sensitivities for Neutrino and Dark Matter Experiments

   The TEXONO Collaboration: A.K. Soma🇹🇼 · M.K. Singh🇮🇳 · L. Singh🇹🇼 · G. Kiran Kumar🇹🇼 · F.K. Lin🇹🇼 · Q. Du🇨🇳 · H. Jiang🇨🇳 · S.K. Liu🇨🇳 · J.L. Ma🇨🇳 · V. Sharma🇹🇼 · L. Wang🇨🇳 · Y.C. Wu🇨🇳 and 36 other authors

   Germanium ionization detectors with sensitivities as low as 100 eVee (electron-equivalent energy) open new windows for studies on neutrino and dark matter physics. The relevant physics subjects are summarized. The detectors have to measure physics signals whose amplitude is comparable to that of pedestal electronic noise. To fully exploit this new detector technique, various experimental issues including quenching factors, energy reconstruction and calibration, signal triggering and selection as well as evaluation of their associated efficiencies have to be attended. The efforts and results of a research program to address these challenges are presented.

   ↳ physics.ins-dethep-exnucl-exNucl.Instrum.Meth.A(2016)·124 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.