Mon·May 25, 2015Monday·May 25, 2015

1. 01*

   Antimagnetic rotation and sudden change of electric quadrupole transition strength in 143Eu

   S. Rajbanshi🇮🇳 · S. Roy🇮🇳 · Somnath Nag🇮🇳 · Abhijit Bisoi · S. Saha🇮🇳 · J. Sethi🇮🇳 · T. Trivedi🇮🇳 · T. Bhattacharjee🇮🇳 · S. Bhattacharyya🇮🇳 · S. Chattopadhyay · G. Gangopadhyay🇮🇳 · G. Mukherjee🇮🇳 and 5 other authors

   Lifetimes of the states in the quadrupole structure in 143Eu have been measured using the Doppler shift attenuation method as well as parity of the states in the sequence has been firmly identified from polarization measurement using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B(E2) with spin, along with increasing J (2) /B(E2) values before band crossing, conclusively establish the origin of these states as arising out of antimagnetic rotation. The abrupt increase in the B(E2) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may indicates the crossing of different shears configurations resulting in re-opening of shears structure. The results are well reproduced by numerical calculation within the framework of semi-classical geometric model.

   nucl-exPLB(2015)·24 citations
2. 02*

   Measurement of the Beam-Recoil Polarization in Low-Energy Virtual Compton Scattering from the Proton

   L. Doria🇩🇪 · P. Janssens🇧🇪 · P. Achenbach🇩🇪 · C. Ayerbe Gayoso🇩🇪 · D. Baumann🇩🇪 · I. Bensafa🇫🇷 · M. Benali🇫🇷 · J. Beričič🇸🇮 · J. C. Bernauer🇩🇪 · R. Böhm🇩🇪 · D. Bosnar🇭🇷 · L. Correa🇫🇷 and 29 other authors

   Double-polarization observables in the reaction $\vec{e}p\to e^{\prime }\overrightarrow{p^{\prime }}\gamma$ have been measured at $Q^2=0.33(GeV/c{)}^2$. The experiment was performed at the spectrometer setup of the A1 Collaboration using the 855 MeV polarized electron beam provided by the Mainz Microtron (MAMI) and a recoil proton polarimeter. From the double-polarization observables the structure function $P_{LT}^{\perp }$ is extracted for the first time, with the value $(-15.4\pm 3.3(stat.{)}_{-2.4}^{+1.5}(syst.))Ge{V}^{-2}$, using the low-energy theorem for Virtual Compton Sattering. This structure function provides a hitherto unmeasured linear combination of the generalized polarizabilities of the proton.

   nucl-exhep-exPRC(2015)·15 citations
3. 03*

   Effects of hadronic rescattering on multistrange hadrons in high-energy nuclear collisions

   Shiori Takeuchi🇯🇵 · Koichi Murase🇯🇵 · Tetsufumi Hirano🇯🇵 · Pasi Huovinen🇩🇪 · Yasushi Nara🇯🇵

   We study the effects of hadronic rescattering on hadron distributions in high-energy nuclear collisions by using an integrated dynamical approach. This approach is based on a hybrid model combining (3+1)-dimensional ideal hydrodynamics for the quark gluon plasma (QGP), and a transport model for the hadron resonance gas. Since the hadron distributions are the result of the entire expansion history of the system, understanding the QGP properties requires investigating how rescattering during the hadronic stage affects the final distributions of hadrons. We include multistrange hadrons in our study, and quantify the effects of hadronic rescattering on their mean transverse momenta and elliptic flow. We find that multistrange hadrons scatter less during the hadronic stage than nonstrange particles, and thus their distributions reflect the properties of the system in an earlier stage than the distributions of nonstrange particles.

   ↳ nucl-thhep-phnucl-exPRC(2015)·67 citations
4. 04*

   Production and relevance of cosmogenic radionuclides in NaI(Tl) crystals

   J. Amare🇪🇸 · S. Cebrian🇪🇸 · C. Cuesta🇪🇸 · E. Garcia🇪🇸 · C. Ginestra🇪🇸 · M. Martinez🇪🇸 · M. A. Olivan🇪🇸 · Y. Ortigoza🇪🇸 · A. Ortiz de Solorzano🇪🇸 · C. Pobes🇪🇸 · J. Puimedon🇪🇸 · M. L. Sarsa🇪🇸 · J. A. Villar🇪🇸 · P. Villar🇪🇸

   The cosmogenic production of long-lived radioactive isotopes in materials is an hazard for experiments demanding ultra-low background conditions. Although NaI(Tl) scintillators have been used in this context for a long time, very few activation data were available. We present results from two 12.5 kg NaI(Tl) detectors, developed within the ANAIS project and installed at the Canfranc Underground Laboratory. The prompt data taking starting made possible a reliable quantification of production of some I, Te and Na isotopes with half-lives larger than ten days. Initial activities underground were measured and then production rates at sea level were estimated following the history of detectors; a comparison of these rates with calculations using typical cosmic neutron flux at sea level and a selected description of excitation functions was also carried out. After including the contribution from the identified cosmogenic products in the detector background model, we found that the presence of 3H in the crystal bulk would help to fit much better our background model and experimental data. We have analyzed the cosmogenic production of 3H in NaI, and although precise quantification has not been attempted, we can conclude that it could imply a very relevant contribution to the total background below 15 keV in NaI detectors.

   ↳ physics.ins-dethep-exnucl-exAIP Conf.Proc.(2015)·6 citations
5. 05*

   The $K\bar{K}\pi$ decay of the $f_1(1285)$ and its nature as a $K^{\ast }\bar{K}-cc$ molecule

   F. Aceti🇪🇸 · Ju-Jun Xie🇨🇳 · E. Oset🇪🇸

   We investigate the decay of $f_1(1285)\to \pi K\bar{K}$ with the assumption that the $f_1(1285)$ is dynamically generated from the $K^{\ast }\bar{K}-cc$ interaction. In addition to the tree level diagrams that proceed via $f_1(1285)\to K^{\ast }\bar{K}-cc\to \pi K\bar{K}$, we take into account also the final state interactions of $K\bar{K}\to K\bar{K}$ and $\pi K\to \pi K$. The partial decay width and mass distributions of $f_1(1285)\to \pi K\bar{K}$ are evaluated. We get a value for the partial decay width which, within errors, is in fair agreement with the experimental result. The contribution from the tree level diagrams is dominant, but the final state interactions have effects in the mass distributions. The predicted mass distributions are significantly different from phase space and tied to the $K^{\ast }\bar{K}-cc$ nature of the $f_1(1285)$ state.

   ↳ hep-phhep-exnucl-exnucl-thPLB(2015)·34 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.