Wed·Dec 17, 2014Wednesday·December 17, 2014

1. 01*

   Limitation of multi-particle correlations for studying the event-by-event distribution of harmonic flow in heavy-ion collisions

   Jiangyong Jia🇺🇸 · Sooraj Krishnann

   The sensitivity of flow harmonics from cumulants on the event-by-event flow distribution $p(v_n)$ is investigated using a simple central moment expansion approach. For narrow distribution whose width is much smaller than the mean ${\sigma }_n\ll <v_n>$, the difference between the first three higher-order cumulant estimates $v_n\{4\}$, $v_n\{6\}$ and $v_n\{8\}$ are not very sensitive to the shape of $p(v_n)$. For broad distribution ${\sigma }_n\gtrsim <v_n>$, the higher-order cumulant estimates differ from each other but may change sign and become ill-defined. This sign change arises from the choice of $p(v_n)$, without the need to invoke non-flow effects. Direct extraction of $p(v_n)$ via a data-driven unfolding method is a more preferred approach for flow distribution measurement.

   nucl-exnucl-thPRC(2015)·18 citations
2. 02*

   Bridging a gap between continuum-QCD and ab initio predictions of hadron observables

   Daniele Binosi🇮🇹 · Lei Chang🇦🇺 · Joannis Papavassiliou🇪🇸 · Craig D. Roberts🇺🇸

   Within contemporary hadron physics there are two common methods for determining the momentum-dependence of the interaction between quarks: the top-down approach, which works toward an ab initio computation of the interaction via direct analysis of the gauge-sector gap equations; and the bottom-up scheme, which aims to infer the interaction by fitting data within a well-defined truncation of those equations in the matter sector that are relevant to bound-state properties. We unite these two approaches by demonstrating that the renormalisation-group-invariant running-interaction predicted by contemporary analyses of QCD's gauge sector coincides with that required in order to describe ground-state hadron observables using a nonperturbative truncation of QCD's Dyson-Schwinger equations in the matter sector. This bridges a gap that had lain between nonperturbative continuum-QCD and the ab initio prediction of bound-state properties.

   ↳ nucl-thhep-lathep-phnucl-exPLB(2015)·237 citations
3. 03*

   Constraining nucleon strangeness

   T. J. Hobbs🇺🇸 · Mary Alberg🇺🇸 · Gerald A. Miller🇺🇸

   Determining the nonperturbative $s\bar{s}$ content of the nucleon has attracted considerable interest and been the subject of numerous experimental searches. These measurements used a variety of reactions and place important limits on the vector form factors observed in parity-violating (PV) elastic scattering and the parton distributions determined by deep inelastic scattering (DIS). In spite of this progress, attempts to relate information obtained from elastic and DIS experiments have been sparse. To ameliorate this situation, we develop an interpolating model using light-front wave functions capable of computing both DIS and elastic observables. This framework is used to show that existing knowledge of DIS places significant restrictions on our wave functions. The result is that the predicted effects of nucleon strangeness on elastic observables are much smaller than those tolerated by direct fits to PV elastic scattering data alone. Using our model, we find $-0.024\le {\mu }_s\le 0.035$, and $-0.137\le {\rho }_s^D\le 0.081$ for the strange contributions to the nucleon magnetic moment and charge radius. The model we develop also independently predicts the nucleon's strange spin content $\Delta s$ and scalar density $⟨N|\bar{s}s|N⟩$, and for these we find agreement with previous determinations.

   ↳ nucl-thhep-phnucl-exPRC(2015)·21 citations
4. 04*

   HOLMES - The Electron Capture Decay of 163Ho to Measure the Electron Neutrino Mass with sub-eV sensitivity

   B. Alpert🇺🇸 · M. Balata🇮🇹 · D. Bennett🇺🇸 · M. Biasotti🇮🇹 · C. Boragno🇮🇹 · C. Brofferio🇮🇹 · V. Ceriale🇮🇹 · D. Corsini🇮🇹 · P.K. Day🇺🇸 · M. De Gerone🇮🇹 · R. Dressler🇨🇭 · M. Faverzani🇮🇹 and 26 other authors

   The European Research Council has recently funded HOLMES, a new experiment to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the decay of 163Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with beta spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress allowed to design a sensitive experiment. HOLMES will deploy a large array of low temperature microcalorimeters with implanted 163Ho nuclei. The resulting mass sensitivity will be as low as 0.4 eV. HOLMES will be an important step forward in the direct neutrino mass measurement with a calorimetric approach as an alternative to spectrometry. It will also establish the potential of this approach to extend the sensitivity down to 0.1 eV. We outline here the project with its technical challenges and perspectives.

   ↳ physics.ins-detnucl-exEPJC(2015)·175 citations
5. 05*

   Thermodynamics of pairing transition in hot nuclei

   Lang Liu · Zhen-Hua Zhang · Peng-Wei Zhao🇺🇸

   The pairing correlations in hot nuclei ${}^{162}$Dy are investigated in terms of the thermodynamical properties by covariant density functional theory. The heat capacities $C_V$ are evaluated in the canonical ensemble theory and the paring correlations are treated by a shell-model-like approach, in which the particle number is conserved exactly. A S-shaped heat capacity curve, which agrees qualitatively with the experimental data, has been obtained and analyzed in details. It is found that the one-pair-broken states play crucial roles in the appearance of the S shape of the heat capacity curve. Moreover, due to the effect of the particle-number conservation, the pairing gap varies smoothly with the temperature, which indicates a gradual transition from the superfluid to the normal state.

   ↳ nucl-thnucl-exPRC(2015)·25 citations
6. 06*

   Separation of flow from chiral magnetic effect in U+U collisions using spectator asymmetry

   Sandeep Chatterjee🇮🇳 · Prithwish Tribedy🇮🇳

   We demonstrate that the prolate shape of the Uranium nucleus generates anti-correlation between spectator asymmetry and initial state ellipticity of the collision zone, providing a way to constrain the initial event shape in U+U collisions. As an application, we show that this can be used to separate the background contribution due to flow from the signals of chiral magnetic effect.

   ↳ nucl-thhep-phnucl-exPRC(2015)·36 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.