Fri·Dec 16, 2022Friday·December 16, 2022

1. 01*

   Pion and photon beam initiated backward charmonium or lepton pair production

   Bernard Pire🇫🇷 · Kirill M. Semenov-Tian-Shansky🇰🇷 · Alisa A. Shaikhutdinova🇷🇺 · Lech Szymanowski🇵🇱

   Hard exclusive reactions initiated by pion or photon beams within the near-backward kinematical regime specified by the small Mandelstam variable $-u$ can be studied to access pion-to-nucleon and photon-to-nucleon Transition Distribution Amplitudes (TDAs). Checking the validity of collinear factorized description of pion and photon induced reactions in terms of TDAs allows to test the universality of TDAs between the space-like and time-like regimes that is the indispensable feature of the QCD collinear factorization approach. In this short review we consider the exclusive pion- and photo-production off nucleon of a highly virtual lepton pair (or heavy quarkonium) in the near-backward region. We first employ a simplistic cross channel nucleon exchange model of pion-to-nucleon TDAs to estimate the magnitude of the corresponding cross sections for the kinematical conditions of J-PARC. We then illustrate the flexibility of our approach by building a two parameter model for the photon-to-nucleon TDAs based on preliminary results for near threshold $J/\psi$ photoproduction at JLab and provide our estimates for near-backward $J/\psi$ photoproduction and Timelike Compton Scattering cross sections for the kinematical conditions of JLab and of future EIC and EicC.

   ↳ hep-phhep-exnucl-exnucl-thAAPPS Bull.(2023)·11 citations
2. 02*

   SYNCA: A Synthetic Cyclotron Antenna for the Project 8 Collaboration

   A. Ashtari Esfahani🇺🇸 · S. Böser🇩🇪 · N. Buzinsky🇺🇸 · M. C. Carmona-Benitez🇺🇸 · C. Claessens🇺🇸 · L. de Viveiros🇺🇸 · M. Fertl🇩🇪 · J. A. Formaggio🇺🇸 · L. Gladstone🇺🇸 · M. Grando🇺🇸 · J. Hartse🇺🇸 · K. M. Heeger🇺🇸 and 33 other authors

   Cyclotron Radiation Emission Spectroscopy (CRES) is a technique for measuring the kinetic energy of charged particles through a precision measurement of the frequency of the cyclotron radiation generated by the particle's motion in a magnetic field. The Project 8 collaboration is developing a next-generation neutrino mass measurement experiment based on CRES. One approach is to use a phased antenna array, which surrounds a volume of tritium gas, to detect and measure the cyclotron radiation of the resulting $\beta$-decay electrons. To validate the feasibility of this method, Project 8 has designed a test stand to benchmark the performance of an antenna array at reconstructing signals that mimic those of genuine CRES events. To generate synthetic CRES events, a novel probe antenna has been developed, which emits radiation with characteristics similar to the cyclotron radiation produced by charged particles in magnetic fields. This paper outlines the design, construction, and characterization of this Synthetic Cyclotron Antenna (SYNCA). Furthermore, we perform a series of measurements that use the SYNCA to test the position reconstruction capabilities of the digital beamforming reconstruction technique. We find that the SYNCA produces radiation with characteristics closely matching those expected for cyclotron radiation and reproduces experimentally the phenomenology of digital beamforming simulations of true CRES signals.

   ↳ physics.ins-dethep-exnucl-exJINST(2023)·7 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.