Thu·Feb 5, 2015Thursday·February 5, 2015

1. 01*

   Studies of Transverse-Momentum-Dependent distributions with A Fixed-Target ExpeRiment using the LHC beams (AFTER@LHC)

   L. Massacrier🇫🇷 · M. Anselmino🇮🇹 · R. Arnaldi🇮🇹 · S. J. Brodsky🇺🇸 · V. Chambert🇫🇷 · W. den Dunnen🇩🇪 · J. P. Didelez🇫🇷 · B. Genolini🇫🇷 · E. G. Ferreiro🇪🇸 · F. Fleuret🇫🇷 · Y. Gao🇨🇳 · C. Hadjidakis🇫🇷 and 14 other authors

   We report on the studies of Transverse-Momentum-Dependent distributions (TMDs) at a future fixed-target experiment --AFTER@LHC-- using the $p^{+}$ or Pb ion LHC beams, which would be the most energetic fixed-target experiment ever performed. AFTER@LHC opens new domains of particle and nuclear physics by complementing collider-mode experiments, in particular those of RHIC and the EIC projects. Both with an extracted beam by a bent crystal or with an internal gas target, the luminosity achieved by AFTER@LHC surpasses that of RHIC by up to 3 orders of magnitude. With an unpolarised target, it allows for measurements of TMDs such as the Boer-Mulders quark distributions and the distribution of unpolarised and linearly polarised gluons in unpolarised protons. Using polarised targets, one can access the quark and gluon Sivers TMDs through single transverse-spin asymmetries in Drell-Yan and quarkonium production. In terms of kinematics, the fixed-target mode combined with a detector covering ${\eta }_{\mathrm{lab}}\in [1,5]$ allows one to measure these asymmetries at large $x^{\uparrow }$ in the polarised nucleon.

   nucl-exhep-exInt.J.Mod.Phys.Conf.Ser.(2016)·17 citations
2. 02*

   A high precision TDC based on a multi-phase clock

   Zhong Qi · Xiangting Meng · Deyuan Li · Lei Yang🇺🇸 · Zeen Yao · Dongcang Li

   The design of a high-precision time-to-digital converter (TDC) based on a multiphase clock implemented using a single field-programmable gate array is discussed in this paper. The TDC can increase the resolution of the measurement by using time interpolation. A phase-locked loop is used to generate four multiphase clocks whose frequencies are the same and whose phases are 0{\deg}, 45{\deg}, 90{\deg}, and 135{\deg}. In addition, the duty ratios of the four clocks are 50%. By utilizing four multiphase clocks to make up the interpolation clock, one clock period can be divided into eight uniform parts. The resolution of the TDC can be improved to 1/8 of a clock period. Furthermore, we have also designed a discriminator circuit for identifying the start and stop signals. On the basis of this circuit, the TDC can still measure the time interval of two signals when the start and stop signals are uncertain. The experimental results indicate that the time resolution of the TDC can achieve the theoretical value, and the linearity is very good. The architecture consumes fewer logic cells and is more stable.

   ↳ physics.ins-detnucl-ex1 citation
3. 03*

   The Physics and Nuclear Nonproliferation Goals of WATCHMAN: A WAter CHerenkov Monitor for ANtineutrinos

   M. Askins🇺🇸 · M. Bergevin🇺🇸 · A. Bernstein🇺🇸 · S. Dazeley🇺🇸 · S. T. Dye🇺🇸 · T. Handler🇺🇸 · A. Hatzikoutelis🇺🇸 · D. Hellfeld🇺🇸 · P. Jaffke🇺🇸 · Y. Kamyshkov🇺🇸 · B. J. Land🇺🇸 · J. G. Learned🇺🇸 and 14 other authors

   This article describes the physics and nonproliferation goals of WATCHMAN, the WAter Cherenkov Monitor for ANtineutrinos. The baseline WATCHMAN design is a kiloton scale gadolinium-doped (Gd) light water Cherenkov detector, placed 13 kilometers from a civil nuclear reactor in the United States. In its first deployment phase, WATCHMAN will be used to remotely detect a change in the operational status of the reactor, providing a first- ever demonstration of the potential of large Gd-doped water detectors for remote reactor monitoring for future international nuclear nonproliferation applications. During its first phase, the detector will provide a critical large-scale test of the ability to tag neutrons and thus distinguish low energy electron neutrinos and antineutrinos. This would make WATCHMAN the only detector capable of providing both direction and flavor identification of supernova neutrinos. It would also be the third largest supernova detector, and the largest underground in the western hemisphere. In a follow-on phase incorporating the IsoDAR neutrino beam, the detector would have world-class sensitivity to sterile neutrino signatures and to non-standard electroweak interactions (NSI). WATCHMAN will also be a major, U.S. based integration platform for a host of technologies relevant for the Long-Baseline Neutrino Facility (LBNF) and other future large detectors. This white paper describes the WATCHMAN conceptual design,and presents the results of detailed simulations of sensitivity for the project's nonproliferation and physics goals. It also describes the advanced technologies to be used in WATCHMAN, including high quantum efficiency photomultipliers, Water-Based Liquid Scintillator (WbLS), picosecond light sensors such as the Large Area Picosecond Photo Detector (LAPPD), and advanced pattern recognition and particle identification methods.

   ↳ physics.ins-dethep-exnucl-ex71 citations
4. 04*

   Scintillating bolometers based on ZnMoO${}_4$ and Zn${}^{100}$MoO${}_4$ crystals to search for 0$\nu$2$\beta$ decay of ${}^{100}$Mo (LUMINEU project): first tests at the Modane Underground Laboratory

   D.V. Poda · E. Armengaud · Q. Arnaud · C. Augier · A. Benoît · A. Benoît · L. Bergé · R.S. Boiko · T. Bergmann · J. Blümer · A. Broniatowski · V. Brudanin and 83 other authors

   The technology of scintillating bolometers based on zinc molybdate (ZnMoO${}_4$) crystals is under development within the LUMINEU project to search for 0$\nu$2$\beta$ decay of ${}^{100}$Mo with the goal to set the basis for large scale experiments capable to explore the inverted hierarchy region of the neutrino mass pattern. Advanced ZnMoO${}_4$ crystal scintillators with mass of $\sim$~0.3 kg were developed and Zn${}^{100}$MoO${}_4$ crystal from enriched ${}^{100}$Mo was produced for the first time by using the low-thermal-gradient Czochralski technique. One ZnMoO${}_4$ scintillator and two samples (59 g and 63 g) cut from the enriched boule were tested aboveground at milli-Kelvin temperature as scintillating bolometers showing a high detection performance. The first results of the low background measurements with three ZnMoO${}_4$ and two enriched detectors installed in the EDELWEISS set-up at the Modane Underground Laboratory (France) are presented.

   ↳ physics.ins-detnucl-exNucl.Part.Phys.Proc.(2016)·8 citations
5. 05*

   Reconstructing the final state of Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV

   Ivan Melo🇸🇰 · Boris Tomasik🇸🇰

   We fit the single-hadron transverse-momentum spectra measured in Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV with the blast-wave model that includes production via resonance decays. Common fit to pions, kaons, (anti)protons, and lambdas yields centrality dependence of the freeze-out temperature and transverse expansion velocity. In the most central collisions we see $T=98$ MeV and $⟨v_t⟩=0.654$. The $K^{\ast }$ resonance fits into this picture but the $\varphi$ meson might freeze-out a little earlier. Multistrange baryons seem to decouple at higher temperature and weaker transverse flow. Within our model we observe hints of chemical potential for the charged pions.

   ↳ nucl-thhep-phnucl-exJ.Phys.G(2016)·31 citations
6. 06*

   Production of strange particles in charged jets in p--Pb and Pb--Pb collisions measured with ALICE at the LHC

   Alice Zimmermann (for the ALICE Collaboration)🇩🇪

   Studies of jet production can provide information about the properties of the hot and dense strongly interacting matter created in ultra-relativistic heavy-ion collisions. Specifically, measurement of strange particles in jets may clarify the role of fragmentation processes in the anomalous baryon to meson ratio at intermediate particle pT that was observed in PbPb and, to a lesser extent, in pPb collisions. In this contribution, measurements of the pT spectra of Lambda and Antilambda baryons and K0s mesons produced in association with charged jets in PbPb collisions at sqrt(sNN)=2.76 TeV and pPb collisions at sqrt(sNN)=5.02 TeV are presented. The analysis is based on data which was recorded by ALICE at the LHC, exploiting its excellent particle identification capabilities. The baryon meson ratios of the spectra of strange particles associated with jets are studied for different event activities in p-Pb and are restricted to central events in PbPb. A comparison to the ratios obtained for inclusive particles and for particles stemming from the underlying event as well as to PYTHIA simulations is shown.

   ↳ hep-exnucl-exJ.Phys.Conf.Ser.(2017)·3 citations
7. 07*

   Unexpected Mesons X, Y, Z, ... (tetraquarks? hadron molecules? ...)

   Ya.I. Azimov🇷🇺

   This talk briefly discusses the set of meson resonances discovered in the latest decade. They are frequently treated in the literature as tetraquarks or hadron molecules. Our consideration (using the energy-time uncertainty relation) suggests, however, that the most reasonable description for each of them may be a two- (or more-) component Fock column, with one line being a conventional quark-antiquark pair, and the other line(s) corresponding to a charmed (or beauty) meson-antimeson pair near its threshold. Detailed investigation of decay properties might allow to reveal presence of several Fock components and separate their contributions.

   ↳ hep-phhep-exnucl-exnucl-th2 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.