arXiv subjects

D. P. Petukhov

Publications and source records attributed to D. P. Petukhov.

43 records · Page 3Linked to original sources

arXiv2019

Search for cascade events with Baikal-GVD

Baikal-GVD is a next generation, kilometer-scale neutrino telescope currently under construction in Lake Baikal. GVD is formed by multi-megaton sub-arrays (clusters) and is designed for the detection of astrophysical neutrino fluxes at energies from a few TeV up to 100 PeV. The design of the Baikal-GVD allows one to search for astrophysical neutrinos with flux values measured by IceCube already at early phases of the array construction. We present here preliminary results of the search for high-energy neutrinos via the cascade mode with the Baikal-GVD neutrino telescope.

astro-ph.HE↗

arXiv2019

The Baikal-GVD neutrino telescope: First results of multi-messenger studies

Multi-messenger astronomy is a powerful tool to study the physical processes driving the non-thermal Universe. A combination of observations in cosmic rays, neutrinos, photons of all wavelengths and gravitational waves is expected. The alert system of the Baikal-GVD detector under construction will allow for a fast, on-line reconstruction of neutrino events recorded by the Baikal-GVD telescope and - if predefined conditions are satisfied - for the formation of an alert message to other communities. The preliminary results of searches for high-energy neutrinos in coincidence with GW170817/GRB170817A using the cascade mode of neutrino detection are discussed. Two Baikal-GVD clusters were operating during 2017. The zenith angle of NGC 4993 at the detection time of the GW170817 was 93.3 degrees. No events spatially coincident with GRB170817A were found. Given the non-detection of neutrino events associated with GW170817, upper limits on the neutrino fluence were established.

astro-ph.HE↗

arXiv2019

The Baikal-GVD detector calibration

In April 2019, the Baikal-GVD collaboration finished the installation of the fourth and fifth clusters of the neutrino telescope Baikal-GVD. Momentarily, 1440 Optical Modules (OM) are installed in the largest and deepest freshwater lake in the world, Lake Baikal, instrumenting 0.25 cubic km of sensitive volume. The Baikal-GVD is thus the largest neutrino telescope on the Northern Hemisphere. The first phase of the detector construction is going to be finished in 2021 with 9 clusters, 2592 OMs in total, however the already installed clusters are stand-alone units which are independently operational and taking data from their commissioning. Huge number of channels as well as strict requirements for the precision of the time and charge calibration (ns, p.e.) make calibration procedures vital and very complex tasks. The inter cluster time calibration is performed with numerous calibration systems. The charge calibration is carried out with a Single Photo-Electron peak. The various data acquired during the last three years in regular and special calibration runs validate successful performance of the calibration systems and of the developed calibration techniques. The precision of the charge calibration has been improved and the time dependence of the obtained calibration parameters have been cross-checked. The multiple calibration sources verified a 1.5 - 2.0 ns precision of the in-situ time calibrations. The time walk effect has been studied in detail with in situ specialized calibration runs.

astro-ph.IM↗

arXiv2019

A positioning system for Baikal-GVD

A cubic kilometer scale neutrino telescope Baikal-GVD is currently under construction in Lake Baikal. Baikal-GVD is designed to detect Cerenkov radiation from products of astrophysical neutrino interactions with Baikal water by a lattice of photodetectors submerged between the depths of 1275 and 730 m. The detector components are mounted on flexible strings and can drift from their initial positions upwards to tens of meters. This introduces positioning uncertainty which translates into a timing error for Cerenkov signal registration. A spatial positioning system has been developed to resolve this issue. In this contribution, we present the status of this system, results of acoustic measurements and an estimate of positioning error for an individual component.

astro-ph.IM↗

arXiv2019

The inter-cluster time synchronization systems within the Baikal-GVD detector

Currently in Lake Baikal, a new generation neutrino telescope is being deployed: the deep underwater Cherenkov detector of a cubic-kilometer scale Baikal-GVD. Completion of the first stage of the telescope construction is planned for 2021 with the implementation of 9 clusters. Each cluster is a completely independent unit in all the aspects: triggering, calibration, data transfer, etc. A high-energy particle might leave its trace in more than a single cluster. To be able to merge events caused by such a particle in more clusters, the appropriate inter-cluster time synchronization is vital.

physics.ins-det↗

arXiv2018

Search for high-energy neutrinos from GW170817 with Baikal-GVD neutrino telescope

The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst (GRB) that followed the merger of this binary was also recorded by Fermi-GBM and INTEGRAL, indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the TeV - 100 PeV energy range using Baikal-GVD. No neutrinos directionally coincident with the source were detected within $\pm$500 s around the merger time, as well as during a 14-day period after the GW detection. We derived 90% confidence level upper limits on the neutrino fluence from GW170817 during a $\pm$500 s window centered on the GW trigger time, and a 14-day window following the GW signal under the assumption of an $E^{-2}$ neutrino energy spectrum.

astro-ph.HE↗

arXiv2018

Baikal-GVD: status and prospects

Baikal-GVD is a next generation, kilometer-scale neutrino telescope under construction in Lake Baikal. It is designed to detect astrophysical neutrino fluxes at energies from a few TeV up to 100 PeV. GVD is formed by multi-megaton subarrays (clusters). The array construction started in 2015 by deployment of a reduced-size demonstration cluster named "Dubna". The first cluster in its baseline configuration was deployed in 2016, the second in 2017 and the third in 2018. The full scale GVD will be an array of ~10000 light sensors with an instrumented volume of about 2 cubic km. The first phase (GVD-1) is planned to be completed by 2020-2021. It will comprise 8 clusters with 2304 light sensors in total. We describe the design of Baikal-GVD and present selected results obtained in 2015-2017.

astro-ph.IM↗