Fri·Mar 4, 2016Friday·March 4, 2016

1. 01*

   Nucleon Resonance Physics

   Volker D. Burkert🇺🇸

   Recent results of meson photo-production at the existing electron machines with polarized real photon beams and the measurement of polarization observables of the final state baryons have provided high precision data that led to the discovery of new excited nucleon and $\Delta$ states using multi-channel partial wave analyses procedures. The internal structure of several prominent excited states has been revealed employing meson electroproduction processes. On the theoretical front, lattice QCD is now predicting the baryon spectrum with very similar characteristics as the constituent quark model, and continuum QCD, such as is represented in the Dyson-Schwinger Equations approach and in light front relativistic quark models, describes the non-perturbative behavior of resonance excitations at photon virtuality of $Q^2>1.5Ge{V}^2$. In this talk I discuss the need to continue a vigorous program of nucleon spectroscopy and the study of the internal structure of excited states as a way to reveal the effective degrees of freedom underlying the excited states and their dependence on the distance scale probed.

   nucl-exhep-lathep-phnucl-thFew Body Syst.(2016)·17 citations
2. 02*

   Observation of a $\gamma$-band based on two-quasiparticle configuration in ${}^{70}$Ge

   M. Kumar Raju🇮🇳 · P. V. Madhusudhana Rao🇮🇳 · S. Muralithar🇮🇳 · R. P. Singh🇮🇳 · G. H. Bhat🇮🇳 · J. A. Sheikh · S. K. Tandel🇮🇳 · P. Sugathan🇧🇪 · T. Seshi Reddy · B. V. Thirumala Rao · R. K. Bhowmik🇮🇳

   The structure of ${}^{70}$Ge has been studied through in-beam gamma ray spectroscopy. A new band structure is identified that leads to forking of the ground-state band into two excited bands. Band structures have been investigated using the microscopic triaxial projected shell model approach. The observed forking is demonstrated to result from almost simultaneous band crossing of the two neutron aligned and the \gamma-band built on this two-quasiparticle configuration with the ground-state band.

   nucl-exPRC(2016)·12 citations
3. 03*

   Extension of the energy range of experimental activation cross-sections data of deuteron induced nuclear reactions on indium up to 50 MeV

   F. Tárkányi🇭🇺 · F. Ditrói🇭🇺 · S. Takács🇭🇺 · A. Hermanne🇧🇪 · A.V. Ignatyuk

   The energy range of our earlier measured activation cross-sections data of longer-lived products of deuteron induced nuclear reactions on indium were extended from 40 MeV up to 50 MeV. The traditional stacked foil irradiation technique and non-destructive gamma spectrometry were used. No experimental data were found in literature for this higher energy range. Experimental cross-sections for the formation of the radionuclides ${}^{113,110}$Sn, ${}^{116m,115m,114m,113m,111,110g,109}$In and ${}^{115}$Cd are reported in the 37-50 MeV energy range, for production of ${}^{110}$Sn and ${}^{110g,109}$In these are the first measurements ever. The experimental data were compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS1.6 nuclear model code as listed in the on-line library TENDL-2014.

   nucl-exAppl.Radiat.Isot.(2015)·0 citations
4. 04*

   Probing clustering in excited alpha-conjugate buclei

   B. Borderie🇫🇷 · Ad. R. Raduta🇷🇴 · G. Ademard🇫🇷 · M. F. Rivet🇫🇷 · E. De Filippo🇮🇹 · E. Geraci🇮🇹 · N. Le Neindre🇫🇷 · R. Alba🇮🇹 · F. Amorini🇮🇹 · G. Cardella🇮🇹 · M. Chatterjee🇮🇳 · D. Guinet🇫🇷 and 15 other authors

   The fragmentation of quasi-projectiles from the nuclear reaction ${}^{40}$Ca+${}^{12}$C at 25 MeV per nucleon bombarding energy was used to produce $\alpha$-emission sources. From a careful selection of these sources provided by a complete detection and from comparisons with models of sequential and simultaneous decays, evidence in favor of $\alpha$-particle clustering from excited ${}^{16}O$, ${}^{20}Ne$ and ${}^{24}Mg$ is reported.

   nucl-exPLB(2016)·27 citations
5. 05*

   Scaling of elliptic flow in heavy-ion collisions with the number of constituent quarks in a transport model

   Subhash Singha🇺🇸 · Md. Nasim🇺🇸

   We studied the number of constituent quark scaling (NCQ) behaviour of elliptic flow ($v_2$) under the framework of A Multi-Phase Transport model (AMPT) at both top-RHIC and LHC energies. The NCQ-scaling in $v_2$ holds at top-RHIC energy with AMPT string melting version, while it breaks in Pb+Pb collisions at LHC energy using the same framework. The breaking of NCQ-scaling at LHC energy has been studied by varying the magnitude of parton-parton scattering cross-section and lifetime of hadronic cascade as implemented in AMPT. We find that the breaking of NCQ scaling in Pb+Pb collisions at $\sqrt{s_{NN}}$ =2.76 TeV is independent of the magnitude of parton-parton cross-section and the later stage hadronic interactions. Further we observed that scaling holds in a small collision system like Si+Si at $\sqrt{s_{NN}}$ = 2.76 TeV. We discussed that the breaking of NCQ scaling is possibly due to high phase-space density of constituents quarks in Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV.

   nucl-exPRC(2016)·19 citations
6. 06*

   Isotopic yield in cold binary fission of even-even ${}^{244-258}$Cf isotopes

   K. P. Santhosh🇮🇳 · Annu Cyriac · Sreejith Krishnan

   The cold binary fission of even-even 244-258Cf isotopes has been studied by taking the interacting barrier as the sum of Coulomb and proximity potential. The favorable fragment combinations are obtained from the cold valley plot (plot of driving potential vs. mass number of fragments) and by calculating the yield for charge minimized fragments. It is found that highest yield for 244,246,248Cf isotopes are for the fragments with isotope of Pb (Z=82) as one fragment, whereas for 250Cf and 252Cf isotopes the highest yield is for the fragments with isotope of Hg (Z=80) as one fragment. In the case of 254,256,258Cf isotopes the highest yield is for the fragments with Sn (Z=50) as one fragment. Thus, the fragment combinations with maximum yield reveal the role of doubly magic and near doubly magic nuclei in binary fission. It is found that asymmetric splitting is favoured for Cf isotopes with mass number A < 250 and symmetric splitting is favoured for Cf isotopes with A > 252. In the case of Cf isotope with A=252, there is an equal probability for asymmetric and symmetric splitting. The individual yields obtained for the cold fission of 252Cf isotope are compared with the experimental data taken from the {\gamma}- {\gamma}- {\gamma} coincidences technique using Gammasphere.

   ↳ nucl-thnucl-exNPA(2016)·13 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.