Thu·Mar 30, 2017Thursday·March 30, 2017

1. 01*

   Open heavy flavour and quarkonium production as a function of the multiplicity in pp and p-Pb collisions with ALICE at the LHC

   Lizardo Valencia Palomo (for the ALICE collaboration)🇲🇽

   Due to the large masses of beauty and charm quarks, their production cross sections can be computed in the framework of perturbative Quantum Chromodynamics. The correlation of quarkonium and open heavy-flavour hadron yields with charged particles produced in proton-proton (pp) and proton-lead (p-Pb) collisions can shed light on the interplay between hard and soft mechanisms in particle production. In this proceeding the results from D-meson and J/$\psi$ yields as a function of the charged-particle multiplicity in pp and p-Pb collisions are presented. Comparisons to theoretical models are also discussed.

   ↳ hep-exnucl-ex0 citations
2. 02*

   Imaging ${}^{55}$Fe Electron Tracks in a GEM-based TPC Using a CCD Readout

   N. S. Phan🇺🇸 · E. R. Lee🇺🇸 · D. Loomba🇺🇸

   Images of resolved 5.9 keV electron tracks produced from ${}^{55}$Fe X-ray interactions are presented for the first time using an optical readout time projection chamber (TPC). The corresponding energy spectra are also shown, with the FWHM energy resolution in the 30-40\% range depending on gas pressure and gain. These tracks were produced in low pressure carbon tetrafluoride (CF${}_4$) gas, and imaged with a fast lens and low noise CCD camera system using the secondary scintillation produced in GEM/THGEM amplification devices. The GEM/THGEMs provided effective gas gains of $\gtrsim 2\times 10^5$ in CF${}_4$ at low pressures in the 25-100 Torr range. The ability to resolve such low energy particle tracks has important applications in dark matter and other rare event searches, as well as in X-ray polarimetry. A practical application of the optical signal from ${}^{55}$Fe is that it provides a tool for mapping the detector gain spatial uniformity.

   ↳ physics.ins-detastro-ph.IMhep-exnucl-exJINST(2020)·14 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.