В. В. Соколов
A5061169833- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- SAS software applications and methods
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Astrophysics and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- Calibration and Measurement Techniques
- Relativity and Gravitational Theory
- Astrophysics and Star Formation Studies
- High-pressure geophysics and materials
- Advanced X-ray and CT Imaging
- Nuclear Physics and Applications
- Statistical and numerical algorithms
- Atmospheric Ozone and Climate
- Geophysics and Sensor Technology
- Medical and Biological Sciences
- Astronomical and nuclear sciences
- History and Developments in Astronomy
- Food Industry and Aquatic Biology
Special Astrophysical Observatory
2013-2024
Russian Academy of Sciences
1993-2014
St. Petersburg Department of Steklov Institute of Mathematics
2012
Earthquake Planning and Protection Organization
2010
Isaac Newton Institute
2001-2006
Universitas Indonesia Timur
2004
Development Agency of Serbia
2003
We report on the discovery of two emission features observed in x-ray spectrum afterglow gamma-ray burst (GRB) 16 December 1999 by Chandra X-ray Observatory. These are identified with Ly(alpha) line and narrow recombination continuum hydrogenic ions iron at a redshift z = 1.00 +/- 0.02, providing an unambiguous measurement distance GRB. Line width intensity imply that progenitor GRB was massive star system ejected, before event, quantity approximately 0.01 mass sun velocity 0.1 speed light,...
GRB 160821B is a short duration gamma-ray burst (GRB) detected and localized by the Neil Gehrels Swift Observatory in outskirts of spiral galaxy at z=0.1613, projected physical offset 16 kpc from galaxy's center. We present X-ray, optical/nIR radio observations its counterpart model them with two distinct components emission: standard afterglow, arising interaction relativistic jet surrounding medium, kilonova, powered radioactive decay sub-relativistic ejecta. Broadband modeling afterglow...
We present photometry and spectroscopy of the type IIP supernova 2009bw in UGC 2890 from few days after outburst to 241 days. The light curve SN during photospheric phase is similar that normal SNe but with brighter peak plateau (Mmax R = -17.82 mag, Mplateau -17.37 mag). luminosity drop nebular one fastest ever observed, ~2.2 mag about 13 radioactive tail bolometric indicates amount ejected 56 Ni \approx 0.022 M\odot. spectra reveal high velocity lines H{\alpha} H{\beta} until 105 shock...
We present ground-based and HST optical observations of the transients (OTs) long-duration Gamma Ray Bursts (GRBs) 060729 090618, both at a redshift z = 0.54. For GRB 060729, bumps are seen in light curves (LCs), late-time broadband spectral energy distributions (SEDs) OT resemble those local type Ic supernovae (SNe). dense sampling our has allowed us to detect well-defined LCs, as well change colour, that indicative coming from core-collapse SN. The accompanying SNe for events individually...
We present the low-resolution spectroscopic and UBVRI broad-band photometric investigations of Type IIb supernova 2011fu, discovered in UGC 01626.The follow-up this event has been initiated a few days after explosion covers period about 175 days.The early-phase light curve shows rise followed by steep decay all bands shares properties very similar to that seen case SN 1993J, with possible detection adiabatic cooling phase.Modelling quasi-bolometric suggests progenitor had an extended (∼ 1 ×...
Aims. GRB 190829A (z = 0.0785), detected by Fermi and Swift with two emission episodes separated a quiescent gap of ~40 s, was also observed the H.E.S.S. telescopes at Very-High Energy (VHE). We present 10.4m GTC observations afterglow underlying supernova compare it against similar 180728A discuss implications on physical mechanisms producing these GRBs. Methods. multi-band photometric data along spectroscopic follow-up taken telescope. Together from prompt emission, are used to understand...
Observations of the extraordinarily bright optical afterglow (OA) GRB 991208 started 2.1 d after event. The flux decay constant OA in R-band is -2.30 +/- 0.07 up to 5 d, which very likely due jet effect, and that it followed by a much steeper with -3.2 0.2, fastest one ever seen OA. A negative detection several all-sky films taken simultaneously event implies either previous additional break prior 2 occurrence (as expected from effect). existence second might indicate steepening electron...
We present broad band photometry and spectroscopic observations of the host galaxy GRB 030329. Analysis spectral emission lines shows that is likely a low metallicity (Z~0.004). The energy distribution (SED) constructed with photometric points has been fitted using synthetic observational templates. best SED fit obtained starburst template an age ~150 Myr extinction Av~0.6. find 030329 subluminous (L~0.016 L*) stellar mass >~10^8 Mo. Three independent diagnostics, based on restframe UV...
We present optical photometric and low-resolution spectroscopic observations of the Type II plateau supernova (SN) 2008in, which occurred in outskirts nearly face-on spiral galaxy M 61. Photometric data X-rays, ultraviolet near-infrared bands have been used to characterize this event. The SN field was imaged with ROTSE-IIIb telescope about seven days before explosion. This allowed us constrain epoch shock breakout JD = 2454825.6. duration phase, as derived from monitoring, ~ 98 days. spectra...
We present broad-band flux spectra for the host galaxies of GRB 970508, 980613, 980703, 990123 and 991208 obtained with 6-m telescope SAO RAS. The comparison these template spectral energy distributions (SEDs) local starburst different morphological types shows that hosts are best fitted by properties SEDs there is a significant internal extinction in galaxies. derived absolute magnitudes making use To create theoretical templates we performed population synthesis modeling continuum...
Aims.We present multiwavelength (X-ray/optical/near-infrared/millimetre) observations of GRB 051022 between 2.5 h and ~1.15 yr after the event. It is most intense gamma-ray burst (~10-4 erg cm-2) detected by HETE-2, with exception nearby 030329.
We report the early discovery of optical afterglow gamma-ray burst (GRB) 140801A in 137 deg$^2$ 3-$\sigma$ error-box Fermi Gamma-ray Burst Monitor (GBM). MASTER is only observatory that automatically react to all alerts. GRB one few GRBs whose counterpart was discovered solely from its GBM localization. The found by Global Robotic Net 53 sec after receiving alert, making it fastest detection a error-box. Spectroscopy obtained with 10.4-m Gran Telescopio Canarias and 6-m BTA SAO RAS reveals...
Abstract Multi-pulsed GRB 190530A, detected by the GBM and LAT onboard Fermi, is sixth most fluent burst so far. This paper presents timing, spectral, polarimetric analysis of prompt emission observed using AstroSat Fermi to provide insight into radiation mechanisms. The time-integrated spectrum shows conclusive proof two breaks due peak energy a second lower break. Time-integrated (55.43 ± 21.30 %) as well time-resolved polarization measurements, made Cadmium Zinc Telluride Imager (CZTI)...
GRB 021004 is one of the best sampled gamma-ray bursts (GRB) to date, although nature its light curve still being debated. Here we present a large amount (107) new optical, near-infrared (NIR) and millimetre observations, ranging from 2 hours more than year after burst. Fitting multiband data model based on multiple energy injections suggests that at least 7 refreshed shocks took place during evolution afterglow, implying total release (collimated within an angle 1.8 deg) ~ 8x10^51 erg....
ABSTRACT Optical, near-infrared (NIR) photometric and spectroscopic studies, along with the optical imaging polarimetric results for SN 2012au, are presented in this article to constrain nature of progenitor other properties. Well-calibrated multiband data (from –0.2 +413 d since B-band maximum) were used compute bolometric light curve perform semi-analytical light-curve modelling using minim code. A spin-down millisecond magnetar-powered model explains observed evolution 2012au reasonably....
We present multiwavelength (optical/near infrared/millimetre) observations of a short duration gamma-ray burst detected by Swift (GRB 050509b) collected between 0 seconds and ∼18.8 days after the event.No optical, near infrared or millimetre emission has been in spite well localised X-ray afterglow, confirming elusiveness events.We also discuss possibility being located cluster galaxies at z = 0.225 beyond.In former case, spectral energy distribution neighbouring, potential host galaxy,...
Abstract We investigate the prompt emission and afterglow properties of short-duration gamma-ray burst (sGRB) 130603B another eight sGRB events during 2012–2015, observed by several multiwavelength facilities including Gran Canarias Telescope 10.4 m telescope. Prompt high energy data were obtained INTEGRAL-SPI-ACS, Swift-BAT, Fermi-GBM satellites. The INTEGRAL in range 0.1–10 MeV for 130603B, 140606A, 140930B, 141212A, 151228A do not show any signature extended or precursor activity their...
Context. Dark gamma-ray bursts (GRBs) constitute a significant fraction of the GRB population. In this paper, we present multi-wavelength analysis (both prompt emission and afterglow) an intense (3.98 × 10 −5 erg cm −2 using Fermi -Gamma-Ray Burst Monitor) two-episodic 150309A observed early on until ∼114 days post burst. Despite strong emission, no optical afterglow was detected for However, discovered near-infrared (NIR) ( K S -band), ∼5.2 h burst, with CIRCE instrument mounted at 10.4 m...
We present the results of broad-band photometry nearby middle-aged radio pulsar PSR B0656+14 and its neighborhood obtained with 6-meter telescope SAO RAS Hubble Space Telescope. The spectral flux decreases increasing frequency in near-IR range increases near-UV range. increase towards UV can be naturally interpreted as Rayleigh-Jeans tail soft thermal component X-ray spectrum emitted from surface cooling neutron star. Continuation power-law component, which dominates high-energy spectrum, to...
Aims.Understand the shape and implications of multiband ligth curve GRB 050408, an X-ray rich (XRR) burst.
The ejecta composition is an open question in gamma-ray bursts (GRB) physics. Some GRBs possess a quasi-thermal spectral component the time-resolved analysis, suggesting hot fireball origin. Others show featureless non-thermal spectrum known as "Band" function, consistent with synchrotron radiation origin and that jet Poynting-flux-dominated at central engine likely emission region well. There are also showing sub-dominant thermal dominant hybrid composition. Here we report extraordinarily...
ABSTRACT We examine the prospects of high-redshift long gamma-ray bursts (LGRBs) Hubble diagram as a test basic cosmological principles. Analysis allows us to several fundamental principles using directly observed flux–distance–redshift relation. Modern LGRBs data together with correlation between spectral peak energy and isotropic equivalent radiated (the so-called Amati relation) can be used for construction at model-independent level. emphasize observational selection effects, which...