Mon·Mar 27, 2017Monday·March 27, 2017

1. 01*

   Double charge exchange (${}^{11}$B,${}^{11}$Li) reaction for double beta decay response

   K. Takahisa · H. Ejiri🇯🇵 · H. Akimune🇯🇵 · H.Fujita🇯🇵 · R.Matumiya · T.Ohta🇯🇵 · T.Shima🇯🇵 · M. Tanaka🇯🇵 · M. Yosoi🇯🇵

   The (${}^{11}$B,${}^{11}$Li) double charge-exchange reaction (DCER) at $E{(}^{11}$B)/$A$=80 MeV was measured for the first time to demonstrate the feasibility of the reaction for studying neutrino nuclear responses for double beta decays (DBD). The ${}^{13}$C(${}^{11}$B,${}^{11}$Li)${}^{13}$O reaction shows strengths at the ground state and low and high excitation giant resonance regions. The ${}^{56}$Fe (${}^{11}$B,${}^{11}$Li) ${}^{56}$Ni reaction shows the large strengths in the possible double giant resonance region and beyond, but shows no strengths in the low excitation region below 5 MeV, suggesting strong concentration of the DBD strength at the high excitation region. The DCER is used to evaluate the spin isospin strengths relevant to DBD responses.

   nucl-ex29 citations
2. 02*

   Charmonium production in Pb-Pb collisions measured by ALICE at the LHC

   Victor Feuillard (for the ALICE collaboration)🇫🇷

   The ALICE experiment is dedicated to the study of the Quark-Gluon Plasma (QGP), a state of matter where, due to high temperature and density, quarks and gluons are deconfined. One of the probes studied to investigate this state of matter is the production of charmonium states, such as the J/$\psi$ and the $\psi$(2S). Indeed, the presence of the QGP is expected to modify the charmonium production yields, due to a balance between the color screening of the charm quark potential and a recombination mechanism. A suppression of the production yields in heavy ion collisions with respect to pp collisions scaled by the mean number of binary nucleon-nucleon collisions was observed by ALICE in Pb-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{NN}}=2.76$ TeV. The observed suppression is smaller than the one found by PHENIX at an order of magnitude lower collision energy. This behavior can be explained by a stronger contribution from recombination processes at LHC than at lower energies. In this presentation, we report on new results for the charmonium production in Pb-Pb collisions measured at forward rapidity with the the muon spectrometer of ALICE at $\sqrt{s_{NN}}=5.02$ TeV and their comparison with previous results and model predictions.

   nucl-exNucl.Part.Phys.Proc.(2017)·0 citations
3. 03*

   Analysis of pion production data measured by HADES in proton-proton collisions at 1.25 GeV

   G. Agakishiev (7) · A. Balanda (3) · D. Belver (18) · A. Belyaev (7) · J. C. Berger-Chen (10,9) · A. Blanco (2) · M. Böhmer (10) · J. L. Boyard (16) · P. Cabanelas (18) · S. Chernenko (7) · A. Dybczak (3) · E. Epple (10,9) and 89 other authors

   Baryon resonance production in proton-proton collisions at a kinetic beam energy of 1.25 GeV is investigated. The multi-differential data were measured by the HADES collaboration. Exclusive channels with one pion in the final state ($np{\pi }^{+}$ and $pp{\pi }^0$) were put to extended studies based on various observables in the framework of a one-pion exchange model and with solutions obtained within the framework of a partial wave analysis (PWA) of the Bonn-Gatchina group. The results of the PWA confirm the dominant contribution of the $\Delta$(1232), yet with a sizable impact of the $N$(1440) and non-resonant partial waves.

   nucl-exEPJA(2015)·23 citations
4. 04*

   Deep sub-threshold {\phi} production and implications for the K+/K- freeze-out in Au+Au collisions

   J. Adamczewski-Musch · O. Arnold · C. Behnke · A. Belounnas · A. Belyaev · J.C. Berger-Chen · J. Biernat · A. Blanco · C. Blume · M. Böhmer · P. Bordalo · S. Chernenko and 101 other authors

   We present data on charged kaons (K+-) and {\phi} mesons in Au(1.23A GeV)+Au collisions. It is the first simultaneous measurement of K and {\phi} mesons in central heavy-ion collisions below a kinetic beam energy of 10A GeV. The {\phi}/K- multiplicity ratio is found to be surprisingly high with a value of 0.52 +- 0.16 and shows no dependence on the centrality of the collision. Consequently, the different slopes of the K+ and K- transverse-mass spectra can be explained solely by feed- down, which substantially softens the spectra of K- mesons. Hence, in contrast to the commonly adapted argumentation in literature, the different slopes do not necessarily imply diverging freeze- out temperatures of K+ and K- mesons caused by different couplings to baryons.

   nucl-exhep-exPLB(2018)·69 citations
5. 05*

   Linking structure and dynamics in $(p,pn)$ reactions with Borromean nuclei: the ${}^{11}$Li$(p,pn){}^{10}$Li case

   M. Gómez-Ramos🇪🇸 · J. Casal🇪🇸 · A.M. Moro🇪🇸

   One-neutron removal $(p,pn)$ reactions induced by two-neutron Borromean nuclei are studied within a Transfer-to-the-Continuum (TC) reaction framework, which incorporates the three-body character of the incident nucleus. The relative energy distribution of the residual unbound two-body subsystem, which is assumed to retain information on the structure of the original three-body projectile, is computed by evaluating the transition amplitude for different neutron-core final states in the continuum. These transition amplitudes depend on the overlaps between the original three-body ground-state wave function and the two-body continuum states populated in the reaction, thus ensuring a consistent description of the incident and final nuclei. By comparing different ${}^{11}$Li three-body models, it is found that the ${}^{11}$Li$(p,pn){}^{10}$Li relative energy spectrum is very sensitive to the position of the $p_{1/2}$ and $s_{1/2}$ states in ${}^{10}$Li and to the partial wave content of these configurations within the ${}^{11}$Li ground-state wave function. The possible presence of a low-lying $d_{5/2}$ resonance is discussed. The coupling of the single particle configurations with the non-zero spin of the ${}^9$Li core, which produces a spin-spin splitting of the states, is also studied. Among the considered models, the best agreement with the available data is obtained with a ${}^{11}$Li model that incorporates the actual spin of the core and contains $\sim$31\% of $p_{1/2}$-wave content in the $n$-${}^9$Li subsystem, in accord with our previous findings for the ${}^{11}$Li(p,d)${}^{10}$Li transfer reaction, and a near-threshold virtual state.

   ↳ nucl-thnucl-exPLB(2017)·22 citations
6. 06*

   Microscopic studies on nuclear spin-isospin properties---a personal perspective on covariant density functional theory

   Haozhao Liang🇯🇵

   Spin and isospin are essential degrees of freedom in nuclear systems, and the relevant studies on their properties play important roles not only in nuclear physics but also in nuclear astrophysics, particle physics, and so on. In this presentation for the IUPAP Young Scientist Prize 2016, I would like to introduce the microscopic studies on nuclear spin-isospin properties in the framework of covariant density functional theory (DFT), by taking a few works that I have been joining in as examples. It is seen that the covariant scheme plays an important role in describing the spin properties in a consistent way, such as the spin-orbit splitting, the pseudospin symmetry, etc. Meanwhile, the Fock terms play important roles in describing the isospin properties fully self-consistently, such as the Gamow-Teller and spin-dipole resonances, the isospin-symmetry-breaking corrections to nuclear superallowed $\beta$ transitions, etc. To connect the covariant DFT to more fundamental theories, an \textit{ab initio} relativistic Brueckner-Hartree-Fock theory for finite nuclei is introduced, and a personal perspective for the coming decade is also illustrated.

   ↳ nucl-thnucl-exPoS(2017)·0 citations
7. 07*

   Light-by-Light Scattering Constraint on Born-Infeld Theory

   John Ellis🇬🇧 · Nick E. Mavromatos🇬🇧 · Tevong You🇬🇧

   The recent measurement by ATLAS of light-by-light scattering in LHC Pb-Pb collisions is the first direct evidence for this basic process. We find that it requires the mass scale of a nonlinear Born-Infeld extension of QED to be $\gtrsim 100$~GeV, a much stronger constraint than those derived previously. In the case of a Born-Infeld extension of the Standard Model in which the U(1)${}_{\mathrm{Y}}$ hypercharge gauge symmetry is realized nonlinearly, the limit on the corresponding mass scale is $\gtrsim 90$~GeV, which in turn imposes a lower limit of $\gtrsim 11$~TeV on the magnetic monopole mass in such a U(1)${}_{\mathrm{Y}}$ Born-Infeld theory.

   ↳ hep-phhep-exhep-thnucl-ex+1PRL(2017)·183 citations
8. 08*

   On-Line Cluster Reconstruction Of GEM Detector Based On FPGA Technology

   Hui-Yin Wu · He-Run Yang · Wei Zhang🇨🇳 · Jian-Jin Zhou · Sheng-Ying Zhao🇨🇳 · Chen-Gui Lu🇨🇳 · Jun-Wei Zhang · Bi-Tao Hu · Yi Zhang🇨🇳 · Wen-Quan Cao

   In this work, a serial on-line cluster reconstruction technique based on FPGA technology was developed to compress experiment data and reduce the dead time of data transmission and storage. At the same time, X-ray imaging experiment based on a two-dimensional positive sensitive triple GEM detector with an effective readout area of 10 cm*10 cm was done to demonstrate this technique with FPGA development board. The result showed that the reconstruction technology was practicality and efficient. It provides a new idea for data compression of large spectrometers.

   ↳ physics.ins-detnucl-ex0 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.