Tue·Sep 25, 2018Tuesday·September 25, 2018

1. 01*

   Erratum: Observation of $D^0$ meson nuclear modifications in Au+Au collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}$ = 200 GeV

   STAR Collaboration: J. Adam · L. Adamczyk · J. R. Adams · J. K. Adkins · G. Agakishiev · M. M. Aggarwal · Z. Ahammed · I. Alekseev · D. M. Anderson · R. Aoyama · A. Aparin · D. Arkhipkin and 343 other authors

   In this erratum we report changes on the $D^0$ $p_T$ spectra and nuclear modification factor ($R_{AA}$) in Au+Au collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}$ = 200 GeV by fixing the errors in the efficiency and selection criteria that affected the Au+Au results. The p+p reference spectrum has changed as well and is updated with new fragmentation parameters.

   nucl-exPRL(2014)·314 citations
2. 02*

   Effect of limited statistics on higher order cumulants measurement in heavy-ion collision experiments

   Ashish Pandav🇮🇳 · Debasish Mallick🇮🇳 · Bedangadas Mohanty🇮🇳

   We have studied the effect of limited statistics of data on measurement of the different order of cumulants of net-proton distribution assuming that the proton and antiproton distributions follow Possionian and Binomial distributions with initial parameters determined from experimental results for two top center of mass energies ($\sqrt{s_{\mathrm{NN}}}=200$ and $62.4$ GeV) in most central ($0-5$%) Au$+$Au collisions at Relativistic Heavy Ion Collider (RHIC). In this simulation, we observe that the central values for higher order cumulants have a strong dependence on event sample size and due to statistical randomness the central values of higher order cumulants could become negative. We also present a study on the determination of the statistical error on cumulants using delta theorem, bootstrap and sub-group methods and verified their suitability by employing a Monte Carlo procedure. Based on our study we find that the bootstrap method provides a robust way for statistical error estimation on high order cumulants. We also present the exclusion limits on the minimum event statistics needed for determination of cumulants if the signal strength (phase transition or critical point) is at a level of $5$% and $10$% above the statistical level. This study will help the experiments to arrive at the minimum required event statistics and choice of proper method for statistical error estimation for high order cumulant measurements.

   nucl-exhep-exnucl-thNPA(2019)·28 citations
3. 03*

   Resonances of unbound quantum many-body systems of nuclei

   B. S. Hu🇨🇳 · Q. Wu🇨🇳 · Z. H. Sun🇨🇳 · F. R. Xu🇨🇳

   Resonance is a general phenomenon which can happen in classic or quantum systems. An unbound many-body quantum system can undergo a self-resonant process. It has long been a challenge how to describe unbound many-body quantum systems in resonances. In this paper, we develop a novel first-principles method that is capable of describing resonant quantum systems. We exploit, for the first time, the advanced in-medium similarity renormalization group (IMSRG) in the complex-energy Gamow-Berggren representation with resonance and non-resonant continuum. The ab initio Gamow IMSRG has broad applications, such as, to the electromagnetic-interaction systems of atoms, molecules or quantum dots, and strong-interaction atomic nuclei. In the present work, we apply the method to loosely bound or unbound nuclear systems. Carbon and oxygen isotopes have been investigated with an optimized chiral effective field theory potential. The resonant states observed in neutron-rich 22O and 24O are well reproduced. The loose halo structure of the Borromean nucleus 22C is clearly seen by the density calculation, in which the continuum s-waves play a crucial role. Further, we predict low-lying resonant excited states in 22C. This method provides rigorous and tractable theoretical calculations for weakly-bound or unbound open quantum systems.

   ↳ nucl-thcond-mat.str-elnucl-exphysics.opticsJ. Phys. G: Nucl. Part. Phys. 46 (2019) 1…·1 citation
4. 04*

   Jet shapes of isolated photon-tagged jets in PbPb and pp collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV

   CMS Collaboration

   The modification of jet shapes in PbPb collisions, relative to those in pp collisions, is studied for jets associated with an isolated photon. The data were collected with the CMS detector at the LHC at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Jet shapes are constructed from charged particles with track transverse momenta ($p_{\mathrm{T}}$) above 1 GeV/c in annuli around the axes of jets with $p_{\mathrm{T}}^{\mathrm{jet}}$ $>$ 30 GeV/c associated with an isolated photon with $p_{\mathrm{T}}^{\gamma }$ $>$ 60 GeV/c. The jet shape distributions are consistent between peripheral PbPb and pp collisions, but are modified for more central PbPb collisions. In these central PbPb events, a larger fraction of the jet momentum is observed at larger distances from the jet axis compared to pp, reflecting the interaction between the partonic medium created in heavy ion collisions and the traversing partons.

   ↳ hep-exnucl-exPRL(2019)·100 citations
5. 05*

   Forward-backward multiplicity fluctuations in ultra-relativistic nuclear collisions with wounded quarks and fluctuating strings

   Martin Rohrmoser🇵🇱 · Wojciech Broniowski🇵🇱

   We analyze a generic model where wounded quarks are amended with strings in which both end-point positions fluctuate in spatial rapidity. With the assumption that the strings emit particles independently of one another and with a uniform distribution in rapidity, we are able to analyze the model semi-analytically, which allows for its detailed understanding. Using as a constraint the one-body string emission functions obtained from the experimental data for collisions at $\sqrt{s_{NN}}=200$ GeV, we explore the two-body correlations for various scenarios of string fluctuations. We find that the popular measures used to quantify the longitudinal fluctuations are limited with upper and lower bounds and assume close values for the most likely models of the end-point distributions, which may explain why various approaches yield here very similar results.

   ↳ nucl-thnucl-exPRC(2019)·11 citations
6. 06*

   A Novel Approach to Neutrino-Hydrogen Measurements

   H. Duyang🇺🇸 · B. Guo🇺🇸 · S.R. Mishra🇺🇸 · R. Petti🇺🇸

   The limited statistics of the available (anti)neutrino-hydrogen (H) interactions has been a longstanding impediment for high-energy neutrino physics. We discuss a practical way to achieve accurate (anti)neutrino-hydrogen measurements, addressing the principal limitations of earlier experiments. Interactions on hydrogen are extracted by subtracting measurements on thin dedicated graphite (pure C) and polypropylene (CH${}_2$) targets within a highly segmented low-density detector. A kinematic selection is used to increase the purities to 80-95\% before subtraction. A statistics of $\mathcal{O}(10^6)$ can be realistically achieved in modern neutrino beams for the various $\nu (\bar{\nu })$-H event topologies. The availability of such samples would allow a precise determination of neutrino and antineutrino fluxes, as well as to directly constrain nuclear effects from a comparison with corresponding measurements on heavy materials within the same detector. The (anti)neutrino fluxes and the nuclear smearing are typically the leading sources of systematic uncertainties in long-baseline oscillation experiments. (Anti)neutrino-hydrogen interactions also provide an ideal tool for a wide range of precision tests of fundamental interactions.

   ↳ hep-phhep-exnucl-exnucl-th+1Eur.Phys.J.Plus(2024)·31 citations
7. 07*

   $\bar{K}\bar{D}N$ molecular state as a "$uuds\bar{c}$ pentaquark" in a three-body calculation

   Junko Yamagata-Sekihara🇯🇵 · Takayasu Sekihara🇯🇵

   We predict a new three-body hadronic molecule composed of antikaon $\bar{K}$, anticharm meson $\bar{D}$, and nucleon $N$ with spin/parity $J^P=1/2^{+}$ and isospin $I=1/2$. This state behaves like an explicit pentaquark state because its minimal quark configuration is $uuds\bar{c}$ or $udds\bar{c}$. Owing to the attraction between every pair of two hadrons, in particular the $\bar{K}\bar{D}$ attraction which dynamically generates $D_{s0}(2317{)}^{-}$ and $\bar{K}N$ attraction which dynamically generates $\Lambda (1405)$, the $\bar{K}\bar{D}N$ system is bound, and its eigenenergy is calculated as $3244-17i$ MeV in a nonrelativistic three-body potential model. We discuss properties of this $\bar{K}\bar{D}N$ quasibound state which emerge uniquely in three-body dynamics.

   ↳ nucl-thhep-phnucl-exPRC(2019)·4 citations
8. 08*

   The microscopic mechanism behind the fission-barrier asymmetry (II): The rare-earth region $50<Z<82$ and $82<N<126$

   T. Ichikawa🇯🇵 · P. Möller🇺🇸

   It is well known that most actinides fission into fragments of unequal size. The first attempt to understand this difference suggested that division leading to one of the fragments being near doubly magic ${}^{132}$Sn is favored by gain in binding energy. After the Strutinsky shell-correction method was developed an alternative idea that gained popularity was that the fission saddle might be lower for mass-asymmetric shapes and that this asymmetry was preserved until scission. Recently it was observed [Phys. Rev. Lett. {\bf 105} (2010) 252502] that ${}^{180}$Hg preferentially fissions asymmetrically in contradiction to the fragment-magic-shell expectation which suggested symmetric division peaked around ${}^{90}$Zr, with its magic neutron number $N=50$, so it was presented as a "new type of asymmetric fission". However, in a paper [Phys. Lett. 34B (1971) 349] a "simple" microscopic mechanism behind the asymmetry of the actinide fission saddle points was proposed to be related the coupling between levels of type [40$\Lambda \Omega$] and [51$\Lambda \Omega$]. The paper then generalizes this idea and made the remarkable prediction that analogous features could exist in other regions. In particular it was proposed that in the rare-earth region couplings between levels of type [30$\Lambda \Omega$] and [41$\Lambda \Omega$] would favor mass-asymmetric outer saddle shapes. In this picture the asymmetry of ${}^{180}$Hg is not a "new type of asymmetric fission" but of analogous origin as the asymmetry of actinide fission. This prediction has never been cited in the discussion of the recently observed fission asymmetries in the "new region of asymmetry", in nuclear physics also referred to as the rare-earth region. We show by detailed analysis that the mechanism of the saddle asymmetry in the sub-Pb region is indeed the one predicted half a century ago.

   ↳ nucl-thnucl-exPLB(2019)·33 citations
9. 09*

   Nonperturbative transverse momentum broadening in dihadron angular correlations in $\sqrt{s_{NN}}=200$ GeV proton-nucleus collisions

   C. Aidala · Y. Akiba · M. Alfred · V. Andrieux · N. Apadula · H. Asano · B. Azmoun · V. Babintsev · N.S. Bandara · K.N. Barish · S. Bathe · A. Bazilevsky and 288 other authors

   The PHENIX collaboration has measured high-$p_T$ dihadron correlations in $p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV. The correlations arise from inter- and intra-jet correlations and thus have sensitivity to nonperturbative effects in both the initial and final states. The distributions of $p_{\mathrm{out}}$, the transverse momentum component of the associated hadron perpendicular to the trigger hadron, are sensitive to initial and final state transverse momenta. These distributions are measured multi-differentially as a function of $x_E$, the longitudinal momentum fraction of the associated hadron with respect to the trigger hadron. The near-side $p_{\mathrm{out}}$ widths, sensitive to fragmentation transverse momentum, show no significant broadening between $p$$+$Au, $p$$+$Al, and $p$$+$$p$. The away-side nonperturbative $p_{\mathrm{out}}$ widths are found to be broadened in $p$$+$Au when compared to $p$$+$$p$; however, there is no significant broadening in $p$$+$Al compared to $p$$+$$p$ collisions. The data also suggest that the away-side $p_{\mathrm{out}}$ broadening is a function of $N_{\mathrm{coll}}$, the number of binary nucleon-nucleon collisions, in the interaction. The potential implications of these results with regard to initial and final state transverse momentum broadening and energy loss of partons in a nucleus, among other nuclear effects, are discussed.

   ↳ hep-exnucl-exPRC(2019)·15 citations
10. 10*

    The FAZIA setup: a review on the electronics and the mechanical mounting

    S. Valdré🇮🇹 · G. Casini🇮🇹 · N. Le Neindre🇫🇷 · M. Bini🇮🇹 · A. Boiano🇮🇹 · B. Borderie🇫🇷 · P. Edelbruck🇫🇷 · G. Poggi🇮🇹 · F. Salomon🇫🇷 · G. Tortone🇮🇹 · R. Alba🇮🇹 · S. Barlini🇮🇹 and 69 other authors

    In this paper the technological aspects of the FAZIA array will be explored. After a productive commissioning phase, FAZIA blocks started to measure and give very useful data to explore the physics of Fermi energy heavy-ion reactions. This was possible thanks to many technical measures and innovations developed in the commissioning phase and tuned during the first experimental campaigns. This paper gives a detailed description of the present status of the FAZIA setup from the electronic and mechanical point of view, trying also to trace a path for new improvements and refinements of the apparatus.

    ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2019)·41 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.