Fri·May 1, 2015Friday·May 1, 2015

1. 01*

   Excitation functions of the nat-Ta(p,x)178m2Hf and nat-W(p,x)178m2Hf reactions at energies up to 2600 MeV

   Yu. E. Titarenko · V. F. Batyaev · K.V. Pavlov · A. Yu. Titarenko · V. M. Zhivun · M. V. Chauzova · A. V. Ignatyuk · S. G. Mashnik🇺🇸 · S. Leray🇫🇷 · A. Boudard🇫🇷 · J.-C. David🇫🇷 · D. Mancusi🇫🇷 and 6 other authors

   Due to potential level of energy intensity 178m2Hf is an extremely interesting isomer. One possible way to produce this isomer is irradiation of nat-Ta or nat-W samples with high energy protons. Irradiation of nat-Ta and nat-W samples performed for other purposes provides an opportunity to study the corresponding reactions. This paper pre-sents the 178m2Hf independent production cross sections for both targets measured by the gamma-ray spectrometry method. The reaction excitation functions have been obtained for the proton energies from 40 up to 2600 MeV. The experimental results were compared with calculations by various versions of the intranuclear cascade model in the well-known codes: ISABEL, Bertini, INCL4.5+ABLA07, PHITS, CASCADE07 and CEM03.02. The isomer ratio for the nat-Ta(p,x)178m2Hf reaction is evaluated on the basis of the available data.

   nucl-exNucl.Instrum.Meth.A(2016)·1 citation
2. 02*

   De-Confinement in small systems: Clustering of color sources in high multiplicity $\bar{p}$p collisions at $\sqrt{s}$= 1.8 TeV

   L. G. Gutay🇺🇸 · A. S. Hirsch🇺🇸 · C. Pajares🇪🇸 · R. P. Scharenberg🇺🇸 · B. K. Srivastava🇺🇸

   It is shown that de-confinement can be achieved in high multiplicity non jet $\bar{p}$p collisions at $\sqrt{s}$= 1.8 TeV Fermi National Accelerator Laboratory(FNAL- E735) experiment. Previously the evidence for de-confinement was the demonstrated by the constant freeze out energy density in high multiplicity events. In this paper we use the same data but analyze the transverse momentum spectrum in the framework of the clustering of color sources. The charged particle pseudorapidities densities in the range 7.0 $\le ⟨d{N}_c/d\eta ⟩\le$26.0 are considered. Results are presented for both thermodynamic and transport properties. The initial temperature and energy density are obtained and compared with the Lattice Quantum Chromo Dynamics(LQCD) simulations. The energy density ($\epsilon /T^4$) $\sim$ 11.5 for $⟨d{N}_c/d\eta ⟩\sim$ 25.0 is close to the value for 0-10\% central events in Au+Au collisions at $\sqrt{s_{NN}}$= 200 GeV. The shear viscosity to entropy density ratio($\eta /s$) is $\sim$ 0.2 at the transition temperature. The result for the trace anomaly $\Delta$ is in excellent agreement with LQCD simulations. These results confirm our earlier observation that the de-confined state of matter was created in high multiplicity events in $\bar{p}$p collisions at $\sqrt{s}$=1.8 TeV.

   nucl-exhep-exhep-phIJMPE(2015)·53 citations
3. 03*

   Search for eta-mesic nuclei with WASA-at-COSY

   Wojciech Krzemien🇵🇱 · Pawel Moskal🇵🇱 · Magdalena Skurzok🇵🇱

   We search for an evidence of eta-mesic He with the WASA detector. Two dedicated experiments were performed at the Cooler Synchrotron COSY-Juelich. The experimental method is based on the measurement of the excitation functions for the two reaction channels: dd->3Heppi- and dd->3Henpi0, where the outgoing N-pi pairs originate from the conversion of the eta meson on a nucleon inside the He nucleus.In this contribution, the experimental method is shortly described and the current status of the analysis is presented.

   nucl-exActa Phys.Polon.B(2015)·11 citations
4. 04*

   Thermal photon radiation in high multiplicity p+Pb collisions at the Large Hadron Collider

   C. Shen🇨🇦 · J.-F. Paquet🇨🇦 · G. S. Denicol🇨🇦 · S. Jeon🇨🇦 · C. Gale🇨🇦

   The collective behaviour of hadronic particles has been observed in high multiplicity proton-lead collisions at the Large Hadron Collider (LHC), as well as in deuteron-gold collisions at the Relativistic Heavy-Ion Collider (RHIC). In this work we present the first calculation, in the hydrodynamic framework, of thermal photon radiation from such small collision systems. Owing to their compact size, these systems can reach temperatures comparable to those in central nucleus-nucleus collisions. The thermal photons can thus shine over the prompt background, and increase the low $p_T$ direct photon spectrum by a factor of 2-3 in 0-1% p+Pb collisions at 5.02 TeV. This thermal photon enhancement can therefore serve as a clean signature of the existence of a hot quark-gluon plasma during the evolution of these small collision systems, as well as validate hydrodynamic behavior in small systems.

   ↳ nucl-thhep-phnucl-exPRL(2016)·42 citations
5. 05*

   Response of Multi-strip Multi-gap Resistive Plate Chamber

   Ushasi Datta (a)🇮🇳 · S. Chakraborty (a)🇮🇳 · A. Rahaman (a)🇮🇳 · P. Basu (a)🇮🇳 · J.Basu (a)🇮🇳 · D. Bemmerer (b)🇩🇪 · K. Boretzky (c)🇩🇪 · Z. Elekes (b)🇩🇪 · M. Kempe (b)🇩🇪 · G. Munzenberg (c)🇩🇪 · H. Simon (c)🇩🇪 · M. Sobiella (b)🇩🇪 and 3 other authors

   A prototype of Multi-strip Multi-gap Resistive Plate chamber (MMRPC) with active area 40 cm $\times$ 20 cm has been developed at SINP, Kolkata. Detailed response of the developed detector was studied with the pulsed electron beam from ELBE at Helmholtz-Zentrum Dresden-Rossendorf. In this report the response of SINP developed MMRPC with different controlling parameters is described in details. The obtained time resolution (${\sigma }_t$) of the detector after slew correction was 91.5$\pm$3 ps. Position resolution measured along (${\sigma }_x$) and across (${\sigma }_y$) the strip was 2.8$\pm$0.6 cm and 0.58 cm, respectively. The measured absolute efficiency of the detector for minimum ionizing particle like electron was 95.8$\pm$1.3 $\%$. Better timing resolution of the detector can be achieved by restricting the events to a single strip. The response of the detector was mainly in avalanche mode but a few percentage of streamer mode response was also observed. A comparison of the response of these two modes with trigger rate was studied

   ↳ physics.ins-detnucl-exJINST(2015)·4 citations
6. 06*

   Neutrino Interactions and Long Baseline Physics

   Ulrich Mosel🇩🇪

   This is a very short review of neutrino-nucleus interactions and their influence on the analysis of long-baseline experiments.

   ↳ hep-exhep-phnucl-exnucl-th4 citations
7. 07*

   Physics Potential of an Advanced Scintillation Detector: Introducing THEIA

   Gabriel D. Orebi Gann (for the THEIA Interest Group)🇺🇸

   The recent development of water-based liquid scintillator and the concurrent development of high-efficiency and high-precision-timing light sensors has opened up the possibility for a new kind of large-scale detector capable of a very broad program of physics. The program would span topics in nuclear, high-energy, and astrophysics, ranging from a next-generation neutrinoless double beta decay search capable of covering the inverted hierarchy region of phase space, to supernova neutrino detection, nucleon decay searches, and measurement of the neutrino mass hierarchy and CP violating phase. This paper describes the technical breakthroughs that led to this possibility, and the broad physics program thus enabled. This paper is a summary of a talk presented at the NuPhys 2014 conference in London.

   ↳ physics.ins-dethep-exnucl-ex32 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.