Wed·Jun 20, 2018Wednesday·June 20, 2018

1. 01*

   Production Rate Measurement of Tritium and Other Cosmogenic Isotopes in Germanium with CDMSlite

   SuperCDMS Collaboration: R. Agnese🇺🇸 · T. Aralis🇺🇸 · T. Aramaki🇺🇸 · I.J. Arnquist🇺🇸 · E. Azadbakht🇺🇸 · W. Baker🇺🇸 · D. Barker🇺🇸 · D.A. Bauer🇺🇸 · T. Binder🇺🇸 · M.A. Bowles🇺🇸 · P.L. Brink🇺🇸 · R. Bunker🇺🇸 and 85 other authors

   Future direct searches for low-mass dark matter particles with germanium detectors, such as SuperCDMS SNOLAB, are expected to be limited by backgrounds from radioactive isotopes activated by cosmogenic radiation inside the germanium. There are limited experimental data available to constrain production rates and a large spread of theoretical predictions. We examine the calculation of expected production rates, and analyze data from the second run of the CDMS low ionization threshold experiment (CDMSlite) to estimate the rates for several isotopes. We model the measured CDMSlite spectrum and fit for contributions from tritium and other isotopes. Using the knowledge of the detector history, these results are converted to cosmogenic production rates at sea level. The production rates in atoms/(kg$\cdot$day) are 74$\pm$9 for ${}^3$H, 1.5$\pm$0.7 for ${}^{55}$Fe, 17$\pm$5 for ${}^{65}$Zn, and 30$\pm$18 for ${}^{68}$Ge.

   ↳ physics.ins-detastro-ph.COastro-ph.IMhep-ex+1Astropart.Phys.(2019)·34 citations
2. 02*

   Jet quenching parameter in an expanding QCD plasma

   Edmond Iancu🇫🇷 · Pieter Taels🇮🇹 · Bin Wu🇨🇭

   We study the phenomenon of transverse momentum broadening for a high-$p_T$ parton propagating through a weakly-coupled quark-gluon plasma undergoing boost-invariant longitudinal expansion. We propose a boost-invariant description for this phenomenon, in which the broadening refers to the angular variables $\eta$ (the pseudo-rapidity) and $\varphi$ (the azimuthal angle). The jet quenching parameter $\hat{q}$ which enters this description depends upon the proper time alone. We furthermore consider radiative corrections to $\hat{q}$. As in the case of a static medium, we find potentially large corrections enhanced by a double logarithm. But unlike for the static medium, these corrections are now local in time: they depend upon the local (proper) time characterizing the expansion, and not upon the overall path length. We resum such corrections to all orders into a renormalized jet quenching parameter. The main effect of this resummation is to slow down the decrease of $\hat{q}$ with increasing proper time.

   ↳ hep-phhep-exnucl-exnucl-thPLB(2018)·25 citations
3. 03*

   Inclusive jet production as a probe of polarized PDFs at a future EIC

   Radja Boughezal🇺🇸 · Frank Petriello🇺🇸 · Hongxi Xing🇺🇸

   We present a detailed phenomenological study of polarized inclusive jet production in electron-proton collisions at a future Electron-Ion Collider (EIC). Our analysis is performed at next-to-leading order in perturbative QCD using the numerical code DISTRESS and includes all relevant partonic channels and resolved photon contributions. We elucidate the role of different kinematic regions in probing different aspects of proton and photon structure and study the impact of the EIC collision energy on the measurement of polarized parton distribution functions.

   ↳ hep-phnucl-exnucl-thPRD(2018)·31 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.