Fri·Jun 10, 2016Friday·June 10, 2016

1. 01*

   Ultra-Peripheral Collisions with gold ions in STAR

   Spencer R. Klein (for the STAR Collaboration)🇺🇸

   In 2010, the STAR Collaboration collected 38 million low-multiplicity triggers for ultra-peripheral collision studies. We present new results involving photonuclear interactions in ultra-peripheral relativistic heavy ion collisions (UPCs), based on an analysis of 384,000 photoproduced pion pairs, from $\rho$, $\omega$ and direct ${\pi }^{+}{\pi }^{-}$ pair production.The $\omega$ component is clearly visible through its interference with the $\rho$ peak. The relative amplitudes of the three components have been measured, along with the phase angle between the $\rho$ and $\omega$ components. Using a two-year (2010 and 2011) dataset, we explore higher mass final states, and observe a ${\pi }^{+}{\pi }^{-}$ state with a mass of $1653\pm 10$ MeV and a width of $164\pm 15$ MeV (statistical errors only). The state is at least roughly compatible with the ${\rho }_3(1690)$. The ${\rho }^0$ squared momentum transfer ($t$) spectrum exhibits a spectrum with both coherent and incoherent prodution. The coherent component shows two characteristic diffraction minima, with positions that are sensitive to the hadronic radius of the gold nucleus.

   nucl-exhep-exPoS(2016)·14 citations
2. 02*

   Search for an Isospin I =3 Dibaryon

   P. Adlarson🇸🇪 · W. Augustyniak🇵🇱 · W. Bardan🇵🇱 · M. Bashkanov🇩🇪 · F.S. Bergmann🇩🇪 · M. Berlowski🇵🇱 · H. Bhatt🇮🇳 · A. Bondar🇷🇺 · M. Buescher · H. Calen🇸🇪 · I. Ciepa · H. Clement🇩🇪 and 82 other authors

   Various theoretical calculations based on QCD or hadronic interactions predict that in addition to the recently observed dibaryon resonance $d^{\ast }(2380)$ with $I(J^P)=0(3^{+})$ there should also exist a dibaryon resonance with mirrored quantum numbers $I(J^P)=3(0^{+})$. We report here on a search for such a $NN$-decoupled state in data on the $pp\to pp{\pi }^{+}{\pi }^{+}{\pi }^{-}{\pi }^{-}$ reaction. Since no clear-cut evidence has been found, we give upper limits for the production cross section of such a resonance in the mass range 2280 - 2500 MeV.

   nucl-exhep-exPLB(2016)·24 citations
3. 03*

   The structure effects in polarization and cross section in inelastic A(p,p')X reaction with the 40Ca and 12C nuclei at 1 GeV

   O.V. Miklukho🇷🇺 · A.Yu. Kisselev🇷🇺 · G.M.Amalsky🇷🇺 · V.A. Andreev🇷🇺 · G.E. Gavrilov🇷🇺 · A.A. Izotov🇷🇺 · N.G. Kozlenko🇷🇺 · P.V. Kravchenko · M.P. Levchenko🇷🇺 · D.V. Novinskiy · A.N. Prokofiev🇸🇪 · A.V. Shvedchikov🇷🇺 · S.I. Trush🇷🇺 · A.A. Zhdanov🇷🇺

   The polarization of the secondary protons in inelastic (p,p') reaction on the 40Ca and 12C nuclei at the initial proton energy 1 GeV was measured in the wide range of the scattered proton momenta at a laboratory angle 21 degree. The cross section of the reactions were measured as well. The outgoing protons from the reaction were detected using a magnetic spectrometer equipped with a multiwire-proportional chambers polarimeter. A structure in the polarization and cross section data, related probably to scattering of the nucleon correlation in the nuclei, was observed.

   nucl-exPhys.Atom.Nucl.(2017)·5 citations
4. 04*

   A new technique for elucidating $\beta$-decay schemes which involve daughter nuclei with very low energy excited states

   M. Venhart🇸🇰 · J. L. Wood🇺🇸 · A. J. Boston🇸🇰 · T. E. Cocolios🇬🇧 · L. J. Harkness-Brennan🇬🇧 · R.-D. Herzberg🇬🇧 · D. T. Joss🇬🇧 · D. S. Judson🇬🇧 · J. Kliman🇸🇰 · V. Matousek🇸🇰 · S. Motycak🇸🇰 · R. D. Page🇬🇧 and 4 other authors

   A new technique of elucidating $\beta$-decay schemes of isotopes with large density of states at low excitation energies has been developed, in which a Broad Energy Germanium (BEGe) detector is used in conjunction with coaxial hyper-pure germanium detectors. The power of this technique has been demonstrated on the example of 183Hg decay. Mass-separated samples of 183Hg were produced by a deposition of the low-energy radioactive-ion beam delivered by the ISOLDE facility at CERN. The excellent energy resolution of the BEGe detector allowed $\gamma$ rays energies to be determined with a precision of a few tens of electronvolts, which was sufficient for the analysis of the Rydberg-Ritz combinations in the level scheme. The timestamped structure of the data was used for unambiguous separation of $\gamma$ rays arising from the decay of 183Hg from those due to the daughter decays.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2017)·2 citations
5. 05*

   Statistical analysis of beta decays and the effective value of g_A in the proton-neutron quasiparticle random-phase approximation framework

   Frank F. Deppisch🇬🇧 · Jouni Suhonen🇫🇮

   We perform a Markov Chain Monte Carlo (MCMC) statistical analysis of a number of measured ground-state-to-ground-state single ${\beta }^{+}$/electron-capture and ${\beta }^{-}$ decays in the nuclear mass range A = 62 - 142. The corresponding experimental comparative half-lives (log ft values) are compared with the theoretical ones obtained by the use of the proton-neutron quasiparticle random-phase approximation (pnQRPA) with G-matrix based effective interactions. The MCMC analysis is performed separately for 47 isobaric triplets and 28 more extended isobaric chains of nuclei to extract values and uncertainties for the effective axial-vector coupling constant g_A in nuclear-structure calculations performed in the pnQRPA framework. As far as available, measured half-lives for two-neutrino double beta-minus decays occurring in the studied isobaric chains are analyzed as well.

   ↳ nucl-thhep-exhep-phnucl-exPRC(2016)·46 citations
6. 06*

   Strangeness suppression in the unquenched quark model

   Roelof Bijker🇲🇽 · Hugo Garcia-Tecocoatzi🇲🇽 · Elena Santopinto🇮🇹

   In this contribution, we discuss the strangeness suppression in the proton in the framework of the unquenched quark model. The theoretical results are in good agreement with the values extracted from CERN and JLab experiments.

   ↳ nucl-thhep-exhep-phnucl-exJ.Phys.Conf.Ser.(2016)·0 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.