BDRG and shok instruments for study of GRB prompt emission in michaylo lomonosov space mission

The study of GRB prompt emission (PE) is one of the main goals of the Lomonosov space mission, which is being prepared at Moscow State University. The GRB monitor (BDRG) and the wide-field optical cameras (SHOK) are intended for detection of GRB prompt emission as well as optical counterparts. The BDRG instrument consists of three identical NaI(Tl)/CsI(Tl) (13.0 × 2.0cm ) phoswich detectors, whose axes determine the Cartesian coordinate system. This allows to localize any GRB source on the sky by means of the count rate seen by each detector with an accuracy of ~2 deg. The SHOK instrument consists of two identical wide-field cameras (WFC) directed in such a way that the field of view (FOV) of each WFC overlaps by the corresponding BDRG FOV, which produces a trigger on the WFC in case of a GRB detection. With this setup, the GRB prompt light curve will be obtained in the visible without any delay with respect to gamma-rays, which is crucial for a GRB central engine understanding

Space experiments on-board of lomonosov mission to study gamma-ray bursts and UHECRS

The number of experiments on-board Lomonosov spacecraft are preparing now at SINP MSU in co-operation with other organisations. The main idea of Lomonosov mission is to study extreme astrophysical phenomena, such as cosmic gamma-ray bursts and ultra-high energy cosmic rays. These phenomena connect with processes occurred in very distant astrophysical objects of the Early Universe and give us information about first stages of Universe evolution. Thus, the Lomonosov mission scientific equipment includes several instruments for gamma-ray burst observation in optics, ultra-violet, X-rays and gamma-rays and the wide aperture telescope for ultra-high energy particle study by detection of ionisation light along its tracks in the atmosphere. The main parameters and a brief description of these instruments are presented

Early polarization observations of the optical emission of gamma-ray bursts: GRB 150301B and GRB 150413A

We report early optical linear polarization observations of two gamma-ray burstsmade with the MASTER robotic telescope network. We found the minimum polarization for GRB 150301B to be 8 per cent at the beginning of the initial stage, whereas we detected no polarization for GRB 150413A either at the rising branch or after the burst reached the power-law afterglow stage. This is the earliest measurement of the polarization (in cosmological rest frame) of gamma-ray bursts. The primary intent of the paper is to discover optical emission and publish extremely rare (unique) high-quality light curves of the prompt optical emission of gammaray bursts during the non-monotonic stage of their evolution. We report that our team has discovered the optical counterpart of one of the bursts, GRB 150413A.Fil: Gorbovskoy, E.S.. Lomonosov Moscow State University; Rusia. Moscow State University; RusiaFil: Lipunov, V.M.. Lomonosov Moscow State University; . Moscow State University; RusiaFil: Buckley, D. A. H.. South African Astronomical Observatory; SudáfricaFil: Kornilov, V. G.. Lomonosov Moscow State University; Rusia. Moscow State University; RusiaFil: Balanutsa, P. V.. Lomonosov Moscow State University; Rusia. Moscow State University; RusiaFil: Tyurina, N. V.. Lomonosov Moscow State University; Rusia. Moscow State University; RusiaFil: Kuznetsov, A. S.. Lomonosov Moscow State University; Rusia. Moscow State University; RusiaFil: Kuvshinov, D. A.. Lomonosov Moscow State University; Rusia. Moscow State University; RusiaFil: Gorbunov, I. A.. Lomonosov Moscow State University ; Rusia. Sternberg Astronomical Institute, Moscow State University; RusiaFil: Vlasenko, D.. Lomonosov Moscow State University; RusiaFil: Popova, E.. Lomonosov Moscow State University; Ruanda. Sternberg Astronomical Institute; RusiaFil: Chazov, V. V.. Sternberg Astronomical Institute; Rusia. Lomonosov Moscow State University; RusiaFil: Potter, S.. South African Astronomical Observatory; SudáfricaFil: Kotze, M.. South African Astronomical Observatory; SudáfricaFil: Kniazev, A. Y.. South African Astronomical Observatory; Sudáfrica. Southern African Large Telescope Foundation; SudáfricaFil: Gress, O. A.. Irkutsk State University; RusiaFil: Budnev, N. M.. Irkutsk State University; RusiaFil: Ivanov, K. I.. Irkutsk State University; RusiaFil: Yazev, S. A.. Irkutsk State University; RusiaFil: Tlatov, A. G.. Kislovodsk Solar Station of the Pulkovo Observatory RAS; RusiaFil: Senik, V. A.. Lomonosov Moscow State University; Rusia. Sternberg Astronomical Institute; Rusia. Kislovodsk Solar Station of the Pulkovo Observatory RAS; RusiaFil: Dormidontov, D. V.. Lomonosov Moscow State University; Rusia. Sternberg Astronomical Institute; Rusia. Kislovodsk Solar Station of the Pulkovo Observatory RAS; RusiaFil: Parhomenko, A. V.. Lomonosov Moscow State University; . Pulkovo Observatory Of The Russian Academy Of Sciences; . Sternberg Astronomical Institute; RusiaFil: Krushinski, V. V.. Kislovodsk Solar Station of the Pulkovo Observatory RAS; RusiaFil: Zalozhnich, I. S.. Kislovodsk Solar Station of the Pulkovo Observatory RAS; RusiaFil: Castro Tirado, R. Alberto. Consejo Superior de Investigaciones Científicas; EspañaFil: Sánchez Ramírez, R.. Consejo Superior de Investigaciones Científicas; EspañaFil: Sergienko, Yu.P.. Blagoveschensk Educational State University; RusiaFil: Gabovich, A.. Blagoveschensk Educational State University; RusiaFil: Yurkov, V.V.. Blagoveschensk Educational State University; RusiaFil: Levato, Orlando Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Saffe, Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Mallamaci, Claudio Carlos. Observatorio Astronmico Félix Aguilar; ArgentinaFil: Lopez, C.. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Informática. Observatorio Astronómico Félix Aguilar; ArgentinaFil: Podesta, F.. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Informática. Observatorio Astronómico Félix Aguilar; ArgentinaFil: Vladimirov, V. V.. Lomonosov Moscow State University; Rusia. Sternberg Astronomical Institute, Moscow State University; Rusi

Multi-messenger Observations of a Binary Neutron Star Merger

International audienceOn 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of $\sim 1.7\,{\rm{s}}$ with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg(2) at a luminosity distance of ${40}_{-8}^{+8}$ Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 $\,{M}_{\odot }$. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at $\sim 40\,{\rm{Mpc}}$) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position $\sim 9$ and $\sim 16$ days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta