Browsing by Author "Crivelli P."
Measurement of the intrinsic hadronic contamination in the NA64-e high-purity e plus /e- beam at CERN
(ELSEVIER, 2023/12/01) Andreev Yu. M.; Banerjee D.; Oberhauser B. Banto; Bernhard J.; Bisio P.; Bondi M.; Celentano A.; Charitonidis N.; Chumakov A. G.; Cooke D.; Crivelli P.; Depero E.; Dermenev A. V.; Donskov S. V.; Dusaev R. R.; Enik T.; Frolov V. N.; Gardikiotis A.; Gerassimov S. G.; Gninenko S. N.; Hoesgen M.; Jeckel M.; Kachanov V. A.; Kambar Y.; Karneyeu A. E.; Kekelidze G.; Ketzer B.; Kirpichnikov D. V.; Kirsanov M. M.; Kolosov V. N.; Konorov I. V.; Gertsenberger S. V.; Kasianova E. A.; Kovalenko S. G.; Kramarenko V. A.; Kravchuk L. V.; Krasnikov N. V.; Kuleshov S. V.; Lyubovitskij V. E.; Lysan V.
We present the measurement of the intrinsic hadronic contamination at the CERN SPS H4 beamline configured to transport electrons and positrons at 100 GeV/c. The analysis, performed using data collected by the NA64-e experiment in 2022, is based on calorimetric measurements, exploiting the different interaction mechanisms of electrons and hadrons in the NA64 detector. We determined the contamination by comparing the results obtained using the nominal electron/positron beamline configuration with those from a dedicated setup, in which only hadrons impinged on the detector. We also obtained an estimate of the relative protons, antiprotons and pions yield by exploiting the different absorption probabilities of these particles in matter. We cross-checked our results with a dedicated Monte Carlo simulation for the hadron production at the primary T2 target, finding a good agreement with the experimental measurements.
Search for Light Dark Matter with NA64 at CERN
(2023/10/20) Andreev Yu. M.; Banerjee D.; Oberhauser B. Banto; Bernhard J.; Bisio P.; Celentano A.; Charitonidis N.; Chumakov A. G.; Cooke D.; Crivelli P.; Depero E.; Dermenev A. V.; Donskov S. V.; Dusaev R. R.; Enik T.; Frolov V. N.; Silva R. B. Galleguillos; Gardikiotis A.; Gertsenberger S. V.; Girod S.; Gninenko S. N.; Hoesgen M.; Kachanov V. A.; Kambar Y.; Karneyeu A. E.; Kasianova E. A.; Kekelidze G. D.; Ketzer B.; Kirpichnikov D. V.; Kirsanov M. M.; Kolosov V. N.; Kramarenko V. A.; Kravchuk L. V.; Krasnikov N. V.; Kuleshov S. V.; Lyubovitskij V. E.; Lysan V.; Marini A.; Marsicano L.; Matveev V. A.; Fredes R. Mena; Yanssen R. G. Mena; Bueno L. Molina; Mongillo M.; Peshekhonov D. V; Polyakov V. A.; Radics B.; Salamatin K. M.; Samoylenko V. D.; Sieber H.; Shchukin D. A.; Soto O.; Tikhomirov V. O.; Tlisova I.; Toropin A. N.; Tuzi M.; Vasilishin B. I.; Volkov P. V.; Volkov V. Yu.; Voronchikhin I. V.; Zamora-Saa J.; Zhevlakov A. S.
Thermal dark matter models with particle chi masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. We report on a new search for the sub-GeV chi production through the interaction mediated by a new vector boson, called the dark photon A ' , in collisions of 100 GeV electrons with the active target of the NA64 experiment at the CERN SPS. With 9.37 x 10(11) electrons on target collected during 2016-2022 runs NA64 probes for the first time the well-motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. No evidence for dark matter production has been found. This allows us to set the most sensitive limits on the A ' couplings to photons for masses m(A ') less than or similar to 0.35 GeV, and to exclude scalar and Majorana dark matter with the chi - A ' coupling alpha(D) <= 0.1 for masses 0.001 less than or similar to m(chi) less than or similar to 0.1 GeV and 3m(chi) <= m(A ').