Fri·Jan 22, 2016Friday·January 22, 2016

1. 01*

   Search for double beta decay of ${}^{116}$Cd with enriched ${}^{116}$CdWO${}_4$ crystal scintillators (Aurora experiment)

   F.A. Danevich🇺🇦 · A.S. Barabash🇷🇺 · P. Belli🇮🇹 · R. Bernabei🇮🇹 · F. Cappella🇮🇹 · V. Caracciolo🇮🇹 · R. Cerulli🇮🇹 · D.M. Chernyak🇺🇦 · S. d'Angelo🇮🇹 · A. Incicchitti🇮🇹 · V.V. Kobychev🇺🇦 · S.I. Konovalov🇷🇺 and 7 other authors

   The Aurora experiment to investigate double beta decay of ${}^{116}$Cd with the help of 1.162 kg cadmium tungstate crystal scintillators enriched in ${}^{116}$Cd to 82\% is in progress at the Gran Sasso Underground Laboratory. The half-life of ${}^{116}$Cd relatively to the two neutrino double beta decay is measured with the highest up-to-date accuracy $T_{1/2}=(2.62\pm 0.14)\times 10^{19}$ yr. The sensitivity of the experiment to the neutrinoless double beta decay of ${}^{116}$Cd to the ground state of ${}^{116}$Sn is estimated as $T_{1/2}\ge 1.9\times 10^{23}$ yr at 90\% CL, which corresponds to the effective Majorana neutrino mass limit $⟨m_{\nu }⟩\le (1.2-1.8)$ eV. New limits are obtained for the double beta decay of ${}^{116}$Cd to the excited levels of ${}^{116}$Sn, and for the neutrinoless double beta decay with emission of majorons.

   nucl-exphysics.ins-detJ.Phys.Conf.Ser.(2016)·30 citations
2. 02*

   Specific Heat of Matter Formed in Relativistic Nuclear Collisions

   Sumit Basu🇮🇳 · Sandeep Chatterjee🇮🇳 · Rupa Chatterjee🇮🇳 · Tapan K. Nayak🇮🇳 · Basanta K. Nandi🇮🇳

   We report the excitation energy dependence of specific heat (\cv) of hadronic matter at freeze-out in Au+Au and Cu+Cu collisions at the Relativistic Heavy Ion Collider energies by analyzing the published data on event-by-event mean transverse momentum (\meanpt) distributions. The \meanpt~distributions in finite \pt~ranges are converted to distributions of effective temperatures, and dynamical fluctuations in temperature are extracted by subtracting widths of the corresponding mixed event distributions. The heat capacity per particle at the kinetic freeze-out surface is presented as a function of collision energy, which shows a sharp rise in \cv~below \sNN~=~62.4~GeV. We employ the Hadron Resonance Gas (HRG) model to estimate \cv~at the chemical and kinetic freeze-out surfaces. The experimental results are compared to the HRG and other theoretical model calculations. HRG results show good agreement with data. Model predictions for \cv~at the Large Hadron Collider energy are presented.

   nucl-exhep-phnucl-thPRC(2016)·37 citations
3. 03*

   Femtoscopic measurements in $p$+Pb collisions at $\sqrt{s_{{}_{\text{NN}}}}=5.02$~TeV with ATLAS at the LHC

   Markus K. Koehler (for the ATLAS Collaboration)🇮🇱

   Recent measurements in two-particle correlations in $p$+Pb collisions suggest collective behavior reminiscent of that observed in Pb+Pb. Femtoscopic measurements may provide useful insight on this behavior because they image the spatio-temporal size of the particle emitting region. This proceeding presents identical-pion Hanbury Brown and Twiss (HBT) measurements from ATLAS using one- and three-dimensional correlation functions. Pions are identified using $\text{d}E/\text{d}x$ measured in the pixel detector. Correlation functions and the resulting HBT radii are shown as a function of pair momentum ($k_{\mathrm{T}}$) and collision centrality.

   nucl-exNPA(2016)·1 citation
4. 04*

   New limits on double beta processes in 106-Cd

   V.I. Tretyak🇺🇦 · P. Belli🇮🇹 · R. Bernabei🇮🇹 · V.B. Brudanin🇷🇺 · F. Cappella🇮🇹 · V. Caracciolo🇮🇹 · R. Cerulli🇮🇹 · D.M. Chernyak🇺🇦 · F.A. Danevich🇺🇦 · S. d'Angelo🇮🇹 · A. Di Marco🇮🇹 · A. Incicchitti🇮🇹 and 5 other authors

   A radiopure cadmium tungstate crystal scintillator, enriched in 106-Cd to 66%, with mass of 216 g (106-CdWO4) was used in coincidence with four ultra-low background HPGe detectors contained in a single cryostat to search for double beta decay processes in 106-Cd. New improved half-life limits on the double beta processes in 106-Cd have been set on the level of 1e20-1e21 yr after 13085 h of data taking deep underground (3600 m w.e.) at the Gran Sasso National Laboratories of INFN (Italy). In particular, the limit on the two neutrino electron capture with positron emission T1/2 >1.1e21 yr, has reached the region of theoretical predictions. The resonant neutrinoless double electron captures to the 2718, 2741 and 2748 keV excited states of 106-Pd are restricted on the level of T1/2 > 8.5e20 - 1.4e21 yr.

   nucl-exhep-exJ.Phys.Conf.Ser.(2016)·3 citations
5. 05*

   Origin of the mass splitting of elliptic anisotropy in a multiphase transport model

   Hanlin Li🇨🇳 · Liang He🇺🇸 · Zi-Wei Lin🇺🇸 · Denes Molnar🇺🇸 · Fuqiang Wang🇺🇸 · Wei Xie🇺🇸

   The mass splitting of elliptic anisotropy ($v_2$) at low transverse momentum is considered as a hallmark of hydrodynamic collective flow. We investigate a multiphase transport (AMPT) model where the $v_2$ is mainly generated by an anisotropic escape mechanism, not of the hydrodynamic flow nature, and where mass splitting is also observed. We demonstrate that the $v_2$ mass splitting in AMPT is small right after hadronization (especially when resonance decays are included); the mass splitting mainly comes from hadronic rescatterings, even though their contribution to the overall charged hadron $v_2$ is small. These findings are qualitatively the same as those from hybrid models that combine hydrodynamics with a hadron cascade. We further show that there is no qualitative difference between heavy ion collisions and small system collisions. Our results indicate that the $v_2$ mass splitting is not a unique signature of hydrodynamic collective flow and thus cannot distinguish whether the elliptic flow is generated mainly from hydrodynamics or the anisotropic parton escape.

   ↳ nucl-thnucl-exPRC(2016)·22 citations
6. 06*

   Testing CCQE and 2p2h models in the NEUT neutrino interaction generator with published datasets from the MiniBooNE and MINERvA experiments

   C. Wilkinson🇬🇧 · R. Terri🇬🇧 · C. Andreopoulos🇬🇧 · A. Bercellie🇺🇸 · C. Bronner🇯🇵 · S. Cartwright🇬🇧 · P. de Perio🇨🇦 · J. Dobson🇬🇧 · K. Duffy🇬🇧 · A.P. Furmanski🇬🇧 · L. Haegel🇨🇭 · Y. Hayato🇯🇵 and 17 other authors

   The MiniBooNE large axial mass anomaly has prompted a great deal of theoretical work on sophisticated Charged Current Quasi-Elastic (CCQE) neutrino interaction models in recent years. As the dominant interaction mode at T2K energies, and the signal process in oscillation analyses, it is important for the T2K experiment to include realistic CCQE cross section uncertainties in T2K analyses. To this end, T2K's Neutrino Interaction Working Group has implemented a number of recent models in NEUT, T2K's primary neutrino interaction event generator. In this paper, we give an overview of the models implemented, and present fits to published muon neutrino and muon antineutrino CCQE cross section measurements from the MiniBooNE and MINERvA experiments. The results of the fits are used to select a default cross section model for future T2K analyses, and to constrain the cross section uncertainties of the model. We find a model consisting of a modified relativistic Fermi gas model and multinucleon interactions most consistently describes the available data.

   ↳ hep-exhep-phnucl-exPRD(2016)·71 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.