Mon·Aug 7, 2017Monday·August 7, 2017

1. 01*

   Observation of Coherent Elastic Neutrino-Nucleus Scattering

   D. Akimov🇷🇺 · J.B. Albert🇺🇸 · P. An🇺🇸 · C. Awe🇺🇸 · P.S. Barbeau🇺🇸 · B. Becker🇺🇸 · V. Belov🇷🇺 · A. Brown🇺🇸 · A. Bolozdynya🇷🇺 · B. Cabrera-Palmer🇺🇸 · M. Cervantes🇺🇸 · J.I. Collar🇺🇸 and 69 other authors

   The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross-section is the largest by far of all low-energy neutrino couplings. This mode of interaction provides new opportunities to study neutrino properties, and leads to a miniaturization of detector size, with potential technological applications. We observe this process at a 6.7-sigma confidence level, using a low-background, 14.6-kg CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the Standard Model for this process, are observed in high signal-to-background conditions. Improved constraints on non-standard neutrino interactions with quarks are derived from this initial dataset.

   nucl-exhep-exhep-phnucl-thScience(2017)·1008 citations
2. 02*

   The Electron-Ion Collider: Assessing the Energy Dependence of Key Measurements

   E.C. Aschenauer🇺🇸 · S. Fazio🇺🇸 · J.H. Lee🇺🇸 · H. Mäntysaari🇺🇸 · B.S. Page🇺🇸 · B. Schenke🇺🇸 · T. Ullrich🇺🇸 · R. Venugopalan🇺🇸 · P. Zurita🇺🇸

   We provide an assessment of the energy dependence of key measurements within the scope of the machine parameters for a U.S. based Electron-Ion Collider (EIC) outlined in the EIC White Paper. We first examine the importance of the physics underlying these measurements in the context of the outstanding questions in nuclear science. We then demonstrate, through detailed simulations of the measurements, that the likelihood of transformational scientific insights is greatly enhanced by making the energy range and reach of the EIC as large as practically feasible.

   nucl-exhep-exhep-phnucl-thRept.Prog.Phys.(2019)·205 citations
3. 03*

   Constraints on the chiral magnetic effect using charge-dependent azimuthal correlations in pPb and PbPb collisions at the LHC

   CMS Collaboration

   Charge-dependent azimuthal correlations of same- and opposite-sign pairs with respect to the second- and third-order event planes have been measured in pPb collisions at $\sqrt{s_{\mathrm{NN}}}=$ 8.16 TeV and PbPb collisions at 5.02 TeV with the CMS experiment at the LHC. The measurement is motivated by the search for the charge separation phenomenon predicted by the chiral magnetic effect (CME) in heavy ion collisions. Three- and two-particle azimuthal correlators are extracted as functions of the pseudorapidity difference, the transverse momentum ($p_{\mathrm{t}}$) difference, and the $p_{\mathrm{t}}$ average of same- and opposite-charge pairs in various event multiplicity ranges. The data suggest that the charge-dependent three-particle correlators with respect to the second- and third-order event planes share a common origin, predominantly arising from charge-dependent two-particle azimuthal correlations coupled with an anisotropic flow. The CME is expected to lead to a $v_2$-independent three-particle correlation when the magnetic field is fixed. Using an event shape engineering technique, upper limits on the $v_2$-independent fraction of the three-particle correlator are estimated to be 13% for pPb and 7% for PbPb collisions at 95% confidence level. The results of this analysis, both the dominance of two-particle correlations as a source of the three-particle results and the similarities seen between PbPb and pPb, provide stringent constraints on the origin of charge-dependent three-particle azimuthal correlations and challenge their interpretation as arising from a chiral magnetic effect in heavy ion collisions.

   nucl-exhep-exPRC(2018)·172 citations
4. 04*

   Charged-particle multiplicity distributions over a wide pseudorapidity range in proton-proton collisions at $\sqrt{\mathbf{s}}=$ 0.9, 7 and 8 TeV

   ALICE Collaboration

   We present the charged-particle multiplicity distributions over a wide pseudorapidity range ($-3.4<\eta <5.0$) for pp collisions at $\sqrt{s}=$ 0.9, 7, and 8 TeV at the LHC. Results are based on information from the Silicon Pixel Detector and the Forward Multiplicity Detector of ALICE, extending the pseudorapidity coverage of the earlier publications and the high-multiplicity reach. The measurements are compared to results from the CMS experiment and to PYTHIA, PHOJET and EPOS LHC event generators, as well as IP-Glasma calculations.

   ↳ hep-exnucl-exEPJC(2017)·74 citations
5. 05*

   Neutron-${}^{19}\mathrm{C}$ scattering: Towards including realistic interactions

   A. Deltuva🇱🇹

   Low-energy neutron-${}^{19}$C scattering is studied in the three-body $n+n+{}^{18}$C model using a realistic $nn$ potential and a number of shallow and deep $n$-${}^{18}$C potentials, the latter supporting deeply-bound Pauli-forbidden states that are projected out. Exact Faddeev-type three-body scattering equations for transition operators including two- and three-body forces are solved in the momentum-space partial-wave framework. Phase shift, inelasticity parameter, and cross sections are calculated. For the elastic $n$-${}^{19}$C scattering in the $J^{\Pi }=0^{+}$ partial wave the signatures of the Efimov physics, i.e., the pole in the effective-range expansion and the elastic cross section minimum, are confirmed for both shallow and deep models, but with clear quantitative differences between them, indicating the importance of a proper treatment of deeply-bound Pauli-forbidden states. In contrast, the inelasticity parameter is mostly correlated with the asymptotic normalization coefficient of the ${}^{19}$C bound state. Finally, in the regime of very weak ${}^{19}$C binding and near-threshold (bound or virtual) excited ${}^{20}$C state the standard Efimovian behaviour of the $n$-${}^{19}$C scattering length and cross section was confirmed, resolving the discrepancies between earlier studies by other authors [I. Mazumdar, A. R. P. Rau, V. S. Bhasin, Phys. Rev. Lett. 97 (2006) 062503; M. T. Yamashita, T. Frederico, L. Tomio, Phys. Rev. Lett. 99 (2007) 269201].

   ↳ nucl-thcond-mat.quant-gasnucl-exPLB(2017)·6 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.