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This paper presents a catalogue of gamma-ray bursts (GRBs) that were detected by the instruments onboard the Lomonosov space observatory. The Lomonosov mission gave the first experience of not only multi-wavelength (from optical to gamma) observations of GRBs but also multi-messenger observations of extreme phenomena and GRBs. The detailed light curves and energy spectra of the detected GRBs are presented. The results of the prompt, early an afterglow optical observations of several GRBs are discussed. [ABSTRACT FROM AUTHOR]

The purpose of this research is to present a detailed description of the proposed Convergence space mission on the Russian segment of the International Space Station for the wider scientific community. The key features of the mission are (1) the necessity of creating a new type of multifrequency radio-thermal airborne complexes with a specialized set of operating frequencies and with the formation of algorithms and software for the three-dimensional recovery of the water-vapor field in the lower troposphere and for estimating the horizontal advection and convective latent heat fluxes at different altitudes and with different forms of boundaries of the investigated regions. (2) An important part of the mission is the global monitoring of optical transient activity, including lightning in cloud tropospheric systems and electric discharges in the upper atmosphere, which are accompanied by a variety of short-term optical glows, commonly called transient luminous events. A significant contribution to the elucidation of the physics and the development of models of high-altitude electric discharges is the synchronous operation of the lightning detector and gamma detector to search for and study gamma-ray bursts of terrestrial origin, including those in previously unexplored latitudes, up to ±51°. It seems that the proposed instrumental configuration and integrity of the mission, which includes the synchronous operation of devices of different ranges of electromagnetic radiation (both the microwave range and optical and gamma range) will contribute significantly to the elucidation of the physics of processes of interaction of catastrophic atmospheric phenomena of the hydrodynamic type, i.e., tropical cyclones, with the electrical activity of tropospheric cloud systems (the field of lightning discharges) and activity of high-altitude electric discharges, which, in turn, can serve as a serious experimental basis for the formation of physical ideas about the genesis of gamma-ray outbreaks of terrestrial origin. [ABSTRACT FROM AUTHOR]

Onboard the spacecraft Lomonosov is established two fast, fixed, very wide-field cameras SHOK. The main goal of this experiment is the observation of GRB optical emission before, synchronously, and after the gamma-ray emission. The field of view of each of the cameras is placed in the gamma-ray burst detection area of other devices located onboard the "Lomonosov" spacecraft. SHOK provides measurements of optical emissions with a magnitude limit of ∼ 9 – 10 m on a single frame with an exposure of 0.2 seconds. The device is designed for continuous sky monitoring at optical wavelengths in the very wide field of view (1000 square degrees each camera), detection and localization of fast time-varying (transient) optical sources on the celestial sphere, including provisional and synchronous time recording of optical emissions from the gamma-ray burst error boxes, detected by the BDRG device and implemented by a control signal (alert trigger) from the BDRG. The Lomonosov spacecraft has two identical devices, SHOK1 and SHOK2. The core of each SHOK device is a fast-speed 11-Megapixel CCD. Each of the SHOK devices represents a monoblock, consisting of a node observations of optical emission, the electronics node, elements of the mechanical construction, and the body. [ABSTRACT FROM AUTHOR]

One of the goals of the Lomonosov satellite designed by scientists of Moscow State University is to study the prompt emission of cosmic gamma-ray bursts. This paper describes the gamma-ray burst monitor in the gamma-ray range (the BDRG instrument) and the wide-field optical cameras (the SHOK instrument) for detecting both the gamma-ray burst prompt emission and its precursors. [ABSTRACT FROM AUTHOR]

We present motivations for and study feasibility of a small, rapid-optical/IR response gamma-ray burst (GRB) space observatory. By analyzing existing GRB data, we give realistic detection rates for X-ray and optical/IR instruments of modest size under actual flight conditions. Given new capabilities of fast optical/IR response (~1 s to target) and simultaneous multi-band imaging, such an observatory can have a reasonable event rate, likely leading to new science. Requiring a Swift-like orbit, duty cycle, and observing constraints, a Swift-BAT scaled down to 190 cm² of detector area would still detect and locate about 25 GRB yr-1 for a trigger threshold of 6.5a. About 23% of X-ray located GRB would be detected optically for a 10 cm diameter instrument (~6 yr-1 for the 6.5δ X-ray trigger). [ABSTRACT FROM AUTHOR]

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(T1)/CsI(TI) (13.0 x 2.0 cm Ø) 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We compared fluxes of the 1-100 MeV solar energetic particles (SEP) measured in the interplanetary medium ( ACE) and in the magnetosphere ( Universitetsky-Tatiana, POES-in polar caps, and GOES-11-at geosynchronous orbit) during several SEP events of 2005-2006. Peak intensities of the SEP fluxes inside and outside the magnetosphere were compared for each event. It is shown that observed inside-outside difference depends mainly on direction of interplanetary magnetic field (IMF), on degree of the SEP anisotropy (pitch-angle distribution) in IMF, and on distance of the dayside magnetopause from the Earth. [ABSTRACT FROM AUTHOR]

Millisecond ultraviolet (240-400 nm) and red-infrared (610-800 nm) flashes were detected in the nighttime atmosphere with the scientific payload installed onboard the Universitetsky-Tatiana-2 micro-satellite. Flashes with various numbers of photons, from 10 to 10, were detected within the atmospheric area 300 km in diameter observed by the detector. The flashes differ in duration and temporal profile: from single short flashes ∼1 ms in duration to flashes with a complex profile more than 100 ms in duration. Different global geographic distributions are observed for flashes with different numbers of photons. Flashes with fewer than 10 photons are distributed uniformly over the Earth's map. Flashes with more than 10 photons are concentrated near the equator and above the continents. Series of flashes were observed in one turn of the satellite when flying not only over thunderstorm regions but also over cloudless ones. The flash number distribution has been derived from the ratio of the numbers of red-infrared and ultraviolet photons. As applied to discharges in the upper atmosphere, whose glow is dominated by the emission in the first and second positive systems of molecular nitrogen bands (1PN and 2PN), this distribution is equivalent to the flash altitude distribution in the atmosphere. The observed ratio of the numbers of photons in red-infrared and ultraviolet flashes agrees with the calculated one for electric discharges at altitudes higher than 50 km. In-orbit measurements of the charged particle flux (with a threshold energy for electrons of 1 MeV) provide no evidence for a synchronous occurrence of an ultraviolet flash and a burst in the particle flux in the orbit. [ABSTRACT FROM AUTHOR]

Increases in solar protons and variations in the electron and proton fluxes from the outer radiation belt are studied based on the GLONASS satellite measurements (the circular orbit at an altitude of ∼20000 km with an inclination of ∼65°) performed in December 2006. Indications in the channels, registered protons with energies of Ep = 3–70 MeV and electrons with energies of Ee > 0.04 and >0.8 MeV, are analyzed. The data on electrons with Ee = 0.8–1.2 MeV, measured on the Express-A3 geostationary satellite, are also presented. Before the strong magnetic storm of December 14 (| Dst|max = 146 nT), the maximum of the outer belt electrons with the energy >0.7 MeV was observed at L ∼ 4.5. After the storm, the fluxes of these electrons increased by more than an order of magnitude as compared to the prestorm level, and the maximum of a “new” belt shifted to L < 4 (minimal L reached by the GLONASS orbit). Under quiet geomagnetic conditions, solar protons with the energies >3 MeV fill only high-latitude legs of the GLONASS orbit. During the strong magnetic storm of December 15, the boundary of proton penetration into the magnetosphere almost merged with the orbital maximum of the proton radiation belt. [ABSTRACT FROM AUTHOR]

The complex of scientific pay load installed onboard the research and educational Universitetskii-Tatyana microsatellite of Moscow State University is described. The complex is designed to study charged particles in the near-earth space and ultraviolet emissions of the atmosphere. Data of the measurements of charged particle fluxes in the microsatellite orbit are presented, spectra are calculated, and the dynamics of penetration boundaries for protons of solar cosmic rays (SCR) during geomagnetic disturbances in 2005 is investigated. Intensities of the ultraviolet emission are measured in the entire range of variation of the atmospheric irradiation, as well as intensities of auroras in the polar regions of the Northern and Southern hemispheres. The experimental data on flashes of ultraviolet radiation (transient light phenomena in the upper atmosphere) are considered, and some examples of oscillograms of their temporal development and their distribution over geographical coordinates are presented. [ABSTRACT FROM AUTHOR]