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BMy. CepHH 3. OH3HKA. ACTPOHOMHfl. 2022. №2
The SAND Detector in the DUNE Near Detector System
Laura Pasqualini1'2 (for the DUNE Collaboration) E-mail: laura.pasqualini@bo. infn. it
1Dipartimento di Fisica e Astronomia, Universita di Bologna. Bologna, 40127 Italy 2Istituto Nazionale di Fisica Nucleare, INFN, Sezione di Bologna. Bologna, 40127 Italy
Received January 16, 2022
The Deep Underground Neutrino Experiment (DUNE) will be a world-class, international new generation long-baseline neutrino experiment. To ensure high precision measurements of neutrino oscillation parameters, a sophisticated Near Detector (ND) complex made of three detectors is foreseen. One component, the System for on-Axis Neutrino Detection (SAND), will permanently be located on-axis while the other two will be moved at different off-axis positions. Besides monitoring the beam, SAND will contribute to keep systematic uncertainties on modeling of cross section, nuclear effects and fluxes under control.
Keywords: neutrino physics, SAND detector, DUNE.
English version: Moscow University Physics Bulletin. 2022. 77, No. 2. Pp. 385-386.
The Recent Result of the Carpet-2 Facility and Status of the Carpet-3 Facility
V.S. Romanenko" et al.
(On behalf of The Carpet-3 Collaboration) E-mail: avsromanenko@inr.ru Institute for Nuclear Research, Russian Academy of Sciences. Moscow, 117312 Russia
Received January 16, 2022
In the present work we report on the observation of an excess of gamma-ray candidate events in temporal and spatial coincidence with the IceCube high-energy neutrino alert consistent with the origin in the Cygnus Cocoon region. The observations have been performed with Carpet-2, a surface air-shower detector equipped with a large-area muon detector at the Baksan Neutrino Observatory in the Northern Caucasus. As well as we report about the current state of the Carpet-3 facility, which includes a muon detector with an increased area and an expanded surface array. The main aim of the Carpet-3 facility is the registration of cosmic gamma-rays with energy larger than 100 TeV. Moreover, it gives a possibility to carry out research on the composition of primary cosmic rays around the knee. It is planned that the Carpet-3 EAS array will be operation by the end of 2021.
Keywords: cosmic rays, gamma-rays, ultra-high energy, gamma-ray astronomy, neutrino astronomy.
English version: Moscow University Physics Bulletin. 2022. 77, No. 2. Pp. 393-394.
First Detection of Solar Neutrinos from the CNO Cycle with Borexino
N. Rossia et al.
(On behalf of BOREXINO Collaboration) E-mail: anicola. rossi@lngs. infn. it
Laboratori Nazionali del Gran Sasso, Istituto Nazionale Fisica Nucleare, L'Aquila, Italy
Received January 17, 2022
Stars are fuelled by the fusion of hydrogen into helium via two processes: the «pp chain» and the «CNO cycle». Neutrinos emitted in the core of the Sun are the only direct probe for the investigation of such processes. The Borexino experiment has performed a complete spectroscopy of the neutrinos from the «pp chain», and has recently reported the first experimental evidence of neutrinos from the CNO cycle, never observed before, being this process subdominant in the Sun (about 1% of the solar energy). This experimental evidence of the CNO neutrinos was obtained using the highly radiopure large-volume liquid-scintillator detector of Borexino. Advances in the thermal stabilization of the detector over the last five years enabled us to exploit a method to constrain the rate of Bi-210 contaminating the scintillator, the main background for such a measurement. Since the CNO cycle is dominant in massive starts, this result proves the evidence of the primary mechanism for the stellar conversion of hydrogen into helium in the Universe.
Keywords: solar neutrinos, CNO cycle, liquid organic scintillators, solar models.
English version: Moscow University Physics Bulletin. 2022. 77, No. 2. Pp. 395-398.
