Thu·Jan 10, 2019Thursday·January 10, 2019

1. 01*

   Nuclear level densities and gamma-ray strength functions of ${}^{180,181,182}$Ta

   C.P. Brits🇿🇦 · K.L. Malatji🇿🇦 · M. Wiedeking🇿🇦 · B.V. Kheswa🇿🇦 · S. Goriely🇧🇪 · F.L. Bello Garrote🇳🇴 · D.L. Bleuel🇺🇸 · F. Giacoppo🇳🇴 · A. Gorgen🇳🇴 · M. Guttormsen🇳🇴 · K. Hadynska-Klek🇳🇴 · T.W. Hagen🇳🇴 and 15 other authors

   Particle-$\gamma$ coincidence experiments were performed at the Oslo Cyclotron Laboratory with the ${}^{181}$Ta(d,X) and ${}^{181}$Ta(${}^3$He,X) reactions, to measure the nuclear level densities (NLDs) and $\gamma$-ray strength functions ($\gamma$SFs) of ${}^{180,181,182}$Ta using the Oslo method. The Back-shifted Fermi-Gas, Constant Temperature plus Fermi Gas, and Hartree-Fock-Bogoliubov plus Combinatorial models where used for the absolute normalisations of the experimental NLDs at the neutron separation energies. The NLDs and $\gamma$SFs are used to calculate the corresponding ${}^{181}$Ta(n,$\gamma$) cross sections and these are compared to results from other techniques. The energy region of the scissors resonance strength is investigated and from the data and comparison to prior work it is concluded that the scissors strength splits into two distinct parts. This splitting may allow for the determination of triaxiality and a $\gamma$ deformation of $14.9^{\circ }\pm 1.8^{\circ }$ was determined for ${}^{181}$Ta.

   nucl-exPRC(2019)·15 citations
2. 02*

   Ge Detectors and $0\nu \beta \beta$: The Search for Double Beta Decay with Germanium Detectors: Past, Present and Future

   Frank T. Avignone III🇺🇸 · Steven R. Elliott🇺🇸

   High Purity Germanium Detectors have excellent energy resolution; the best among the technologies used in double beta decay. Since neutrino-less double beta decay hinges on the search for a rare peak upon a background continuum, this strength has enabled the technology to consistently provide leading results. The Ge crystals at the heart of these experiments are very pure; they have no measurable U or Th contamination. The added efforts to reduce the background associated with electronics, cryogenic cooling, and shielding have been very successful, leading to the longevity of productivity. The first experiment published in 1967 by the Milan group of Fiorini, established the benchmark half-life limit $>3\times 10^{20}$ yr. More recently, the \MJ\ and GERDA collaborations have developed new detector technologies that optimize the pulse waveform analysis. As a result, the GERDA collaboration refuted the claim of observation with a revolutionary approach to shielding by immersing the detectors directly in radio-pure liquid argon. In 2018, the \MJ\ collaboration, using a classic vacuum cryostat and high-Z shielding, achieved a background level near that of GERDA by developing very pure materials for use nearby the detectors. Together, GERDA and \MJ\ have provided limits approaching $10^{26}$ yr. In this article, we elaborate on the historical use of Ge detectors for double beta decay addressing the strengths and weaknesses. We also summarize the status and future as many \MJ\ and GERDA collaborators have joined with scientists from other efforts to give birth to the LEGEND collaboration. LEGEND will exploit the best features of both experiments to extend the half-life limit beyond $10^{28}$ yr with a ton-scale experiment.

   nucl-exFront.in Phys.(2019)·22 citations
3. 03*

   Quarkonium production as a function of charged-particle multiplicity in pp and p--Pb collisions measured by ALICE at the LHC

   Dhananjaya Thakur (for the ALICE Collaboration)🇮🇳

   Quarkonium production as a function of the charged-particle multiplicity could provide an insight into particle production processes at the partonic level in hadronic collisions. It is believed that multiple partonic interactions play an important role in particle production and affect both soft and hard processes. The study of correlations between quarkonia and charged-particle multiplicity may provide information about this. In this contribution, ALICE measurements of J$/\psi$ and ${\rm Y}$ production as a function of charged-particle multiplicity are presented for pp collisions at center-of-mass energies $\sqrt{s}$ = 5.02 and 13 TeV. A similar measurement performed in p\textendash Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 8.16 TeV at both forward and backward rapidity is also discussed.

   ↳ hep-exhep-phnucl-exPoS(2019)·3 citations
4. 04*

   Improvement of charge resolution for radioactive heavy ions at relativistic energies using a hybrid detector system

   J.W.Zhao🇨🇳 · B.H.Sun🇨🇳 · L.C. He🇨🇳 · G.S. Li🇨🇳 · W.J. Lin · C.Y. Liu🇺🇸 · Z.Liu🇨🇳 · C.G.Lu · D.P.Shen · Y.Z.Sun · Z.Y.Sun · I.Tanihata🇨🇳 and 13 other authors

   In typical nuclear physics experiments with radioactive ion beams (RIBs) selected by the in-flight separation technique, Si detectors or ionization chambers are usually equipped for the charge determination of RIBs. The obtained charge resolution relies on the performance of these detectors for energy loss determination, and this affects the particle identification capability of RIBs. We present an approach on improving the resolution of charge measurement for heavy ions by using the abundant energy loss information from different types of existing detectors along the beam line. Without altering the beam line and detectors, this approach can improve the charge resolution by more than 12\% relative to the multiple sampling ionization chamber of the best resolution.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2019)·6 citations
5. 05*

   Current and future measurements of semi-inclusive hadron+jet distributions with ALICE

   Jaime Norman (for the ALICE collaboration)🇫🇷

   The measurement of jets recoiling from a trigger hadron in heavy-ion collisions can be used to understand the properties of the Quark Gluon Plasma. Jet-medium interactions cause jets to lose energy in the medium and may modify the jet structure. Jet deflection towards large angles due to scattering off of quasi-particles in the Quark-Gluon Plasma may also occur, which can be studied through a measurement of the hadron-jet acoplanarity. These phenomena can be studied through the semi-inclusive distribution of track-based jets recoiling from a trigger hadron. This contribution presents the latest measurements and prospects of semi-inclusive hadron+jet distributions with ALICE. Constraints on energy loss in p-Pb collisions and future prospects to measure energy loss in smaller systems are shown. A jet shape measurement of N-subjettiness using recoil jets is outlined. Finally, prospects for hadron+jet acoplanarity measurements with ALICE are presented.

   ↳ hep-exnucl-exPoS(2018)·2 citations
6. 06*

   The GlueX Start Counter Detector

   Eric Pooser🇺🇸 · Fernando Barbosa🇺🇸 · Werner Boeglin🇺🇸 · Charles Hutton🇺🇸 · Mark Ito🇺🇸 · Mahmoud Kamel🇺🇸 · Puneet Khetarpal🇺🇸 · Anthony Llodra🇺🇸 · Joseph Sandoval🇺🇸 · Simon Taylor🇺🇸 · Timothy Whitlatch🇺🇸 · Stephanie Worthington🇺🇸 · Carlos Yero🇺🇸 · Benedikt Zihlmann🇺🇸

   The design, simulation, fabrication, calibration, and performance of the GlueX Start Counter detector is described. The Start Counter was designed to operate at integrated rates of up to 9 MHz with a timing resolution in the range of 500 to 825 ps (FWHM). The Start Counter provides excellent solid angle coverage, a high degree of segmentation for background rejection, and can be utilized in the level 1 trigger for the experiment. It consists of a cylindrical array of 30 thin scintillators with pointed ends that bend towards the beam line at the downstream end. Magnetic field insensitive silicon photomultiplier detectors were used as the light sensors.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2019)·33 citations
7. 07*

   Electron Radiated Power in Cyclotron Radiation Emission Spectroscopy Experiments

   A. Ashtari Esfahani🇺🇸 · V. Bansal🇺🇸 · S. Boser🇩🇪 · N. Buzinsky🇺🇸 · R. Cervantes🇺🇸 · C. Claessens🇩🇪 · L. de Viveiros🇺🇸 · P. J. Doe🇺🇸 · M. Fertl🇺🇸 · J. A. Formaggio🇺🇸 · L. Gladstone🇺🇸 · M. Guigue🇺🇸 and 29 other authors

   The recently developed technique of Cyclotron Radiation Emission Spectroscopy (CRES) uses frequency information from the cyclotron motion of an electron in a magnetic bottle to infer its kinetic energy. Here we derive the expected radio frequency signal from an electron in a waveguide CRES apparatus from first principles. We demonstrate that the frequency-domain signal is rich in information about the electron's kinematic parameters, and extract a set of measurables that in a suitably designed system are sufficient for disentangling the electron's kinetic energy from the rest of its kinematic features. This lays the groundwork for high-resolution energy measurements in future CRES experiments, such as the Project 8 neutrino mass measurement.

   ↳ physics.ins-detnucl-exPRC(2019)·36 citations
8. 08*

   Progress toward Barium Tagging in High Pressure Xenon Gas with Single Molecule Fluorescence Imaging

   N. Byrnes🇺🇸 · F. W. Foss Jr.🇺🇸 · B.J.P Jones🇺🇸 · A.D. McDonald🇺🇸 · D.R. Nygren🇺🇸 · P. Thapa🇺🇸 · A. Trinidad (for the NEXT collaboration)

   We present an update on the development of techniques to adapt Single Molecule Fluorescent Imaging for the tagging of individual barium ions in high pressure xenon gas detectors, with the goal of realizing a background-free neutrinoless double beta decay technology. Previously reported progress is reviewed, including the recent demonstration of single barium dication sensitivity using SMFI. We then describe two important advances: 1) the development of a new class of custom barium sensing fluorescent dyes, which exhibit a significantly stronger response to barium than commercial calcium sensing compounds in aqueous solution; 2) the first demonstration of a dry-phase chemosensor for barium ions. This proceeding documents work presented at the 9th Symposium on Large TPCs for Rare Event Detection in Paris, France.

   ↳ physics.ins-detnucl-exJ.Phys.Conf.Ser.(2019)·7 citations
9. 09*

   Interpretation of coincidence data from strip detectors and extraction of absolute cross section using 3-body Monte Carlo simulation method

   S.K. Pandit🇮🇳 · K. Mahata🇮🇳 · A. Shrivastava🇮🇳 · V.V. Parkar🇮🇳 · K. Ramachandran🇮🇳

   Accurate knowledge of the response of the detection system is very crucial for unambiguous interpretation of the experimental data. A simulation code has been developed using the Monte Carlo technique involving 3-body kinematics for the analysis of data obtained with segmented large area Si $\Delta E-E$ detector telescopes in nuclear reaction measurements. Care was taken in the analysis to maximize the angular coverage and statistics. The emphasis is placed to extract the absolute cross sections of the different reaction processes, for which coincident measurements are unavoidable. The estimated detection efficiency of different coincidence events are found to depend on various parameters, e.g., the relative energy of the breakup fragments, incident beam energy of the projectile, ground state $Q$-value of the reaction, the excitation of the ejectile as well as target like nuclei, mass asymmetry of the breakup fragments, detection threshold, and geometric solid angle of the detection setup. The interpretation of the various observables from the exclusive measurements of breakup and transfer breakup reactions is reported.

   ↳ physics.ins-detnucl-exJINST(2019)·2 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.