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Author

O. Koloskov

Bio: O. Koloskov is an academic researcher. The author has contributed to research in topics: Ionosphere & Physics. The author has an hindex of 1, co-authored 2 publications receiving 3 citations.

Papers
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TL;DR: In this paper , the first report of global ionospheric disturbances due to the most powerful Gamma Ray Burst GRB221009A occurred on 9 October 2022, and both daytime and nighttime effects were analyzed in VLF and LF bands.
Abstract: We present the first report of global ionospheric disturbances due to the most powerful Gamma Ray Burst GRB221009A occurred on 9 October 2022. Very Low Frequency (VLF) and Low Frequency (LF) sub-ionospheric radio signals are used to diagnose the effect of the GRB on the lower ionosphere. Both daytime and nighttime effects are analyzed in VLF and LF bands. The magnitude of VLF signal perturbations varied with the propagation condition (day/night), path length, and frequency of the signal. The recovery times for the VLF/LF signals to get back to their pre-GRB levels varied from 2–60 min. Radio signals reflected from the E-region ionosphere for nighttime VLF signals and daytime LF signals showed greater effects compared to the daytime VLF signals reflected from the lower parts of the D-region.

2 citations

Journal ArticleDOI
TL;DR: In this paper , a software-defined radio ionosonde (ISDR) was developed at the Abdus Salam International Centre for Theoretical Physics (Italy) and the Institute of Radio Astronomy (Ukraine) and installed at the Ukrainian Antarctic Station in 2017.
Abstract: This work presents a software-defined radio ionosonde (ISDR) developed at the Abdus Salam International Centre for Theoretical Physics (Italy) and the Institute of Radio Astronomy (Ukraine) and installed at the Ukrainian Antarctic Station in 2017. For the first time, the results of the long-term data comparison of the ISDR with the conventional ionosonde IPS-42 produced by KEL Aerospace are presented and discussed. The matching of the ionograms obtained during the whole year of 2021, as well as a comparison of the critical frequencies and virtual heights of F, E, and Es layers manually scaled from the ionograms showed that the ISDR has a similar level of performance to IPS-42. At the same time, the ISDR is a more versatile instrument that supports a bistatic operation, provides Doppler measurements and polarization information, and has a significantly lower cost and transmission power. Different configurations of the ISDR are considered. The basic configuration allows for using the ISDR as a conventional vertical ionospheric sounder. An enhanced configuration of the ISDR allows for oblique sounding, as well as polarization information that enables the O- and X-propagation modes of the ionospheric signal to be distinguished. The enhanced passive version of the ISDR was successfully tested onboard the research vessel “Noosfera” on distances up to 1,400 km from the transmitting ISDR.

1 citations


Cited by
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Journal ArticleDOI
D. A. Kann, S. Agayeva, V. Aivazyan, S. Alishov, Chad Andrade, S. Antier, A. Baransky, Philippe Bendjoya, Zouhair Benkhaldoun, S. Beradze, D. R. Berezin, M. Boer, Eric Broens, Serge Brunier, Mattia Bulla, O. A. Burkhonov, Eric Burns, Y. B. Chen, M. Conti, Michael W. Coughlin, W. Cui, Frédéric Daigne, Benoit Delaveau, Hadrien A. R. Devillepoix, Tim Dietrich, D. Dornic, Franky Dubois, J.-G. Ducoin, Emeline Durand, P. A. Duverne, Heinz-Bernd Eggenstein, Sh. A. Ehgamberdiev, Anthony Fouad, Mark H. Freeberg, Dirk Froebrich, Ming-Yu Ge, Simone Gervasoni, V. Godunova, P. Gokuldass, Elchin J. Gurbanov, D Han, Elman Hasanov, P. Hello, T. Hussenot-Desenonges, R. Inasaridze, Abdusamatjan Iskandar, N. Ismailov, Asmae Janati, T. J. D. Laz, Shu-Mei Jia, S A Karpov, A. Kaeouach, R. W. Kiendrebeogo, A. Klotz, R Kneip, N. Kochiashvili, N. Kunert, Andrica Lekić, S. Leonini, C. K. Li, W. X. Li, X. B. Li, Jin-Yuan Liao, Ludwig Logie, F. J. Lu, J. Mao, D. Marchais, R. M'enard, David Morris, R. Sh. Natsvlishvili, Vsevolod Nedora, Kristin Noonan, K. Noysena, N. B. Orange, P. T.H. Pang, H Peng, C. Pellouin, J. Peloton, T. Pradier, O. Pyshna, Y. Rajabo, Steve Rau, C. Rinner, J.-P. Rivet, F. D. Romanov, Paolo Rosi, V. Rupchandani, M. Serrau, A. Shokry, A. Simon, K. Smith, O Sokoliuk, Mena Soliman, L. M. Song, Ali Takey, Yusufjon Tillayev, L. M. Tinjaca Ramirez, I. Tosta e Melo, D. Turpin, A. de Ugarte Postigo, Siegfried Vanaverbeke, V. Vasylenko, David Vernet, Z. Vidadi, C. Wang, J. Wang, L. Wang, X. F. Wang, Shaolin Xiong, Y. Xu, W. C. Xue, X. Y. Zeng, S. N. Zhang, H. S. Zhao, Xu Zhao 
TL;DR: In this paper , the optical afterglow of the gamma-ray burst (GRB 221009A) was studied using the GRANDMA+HXMT-LE+XRT data sets augmented with data from the literature up to 60 days.
Abstract: Object GRB 221009A is the brightest gamma-ray burst (GRB) detected in more than 50 yr of study. In this paper, we present observations in the X-ray and optical domains obtained by the GRANDMA Collaboration and the Insight Collaboration. We study the optical afterglow with empirical fitting using the GRANDMA+HXMT-LE data sets augmented with data from the literature up to 60 days. We then model numerically using a Bayesian approach, and we find that the GRB afterglow, extinguished by a large dust column, is most likely behind a combination of a large Milky Way dust column and moderate low-metallicity dust in the host galaxy. Using the GRANDMA+HXMT-LE+XRT data set, we find that the simplest model, where the observed afterglow is produced by synchrotron radiation at the forward external shock during the deceleration of a top-hat relativistic jet by a uniform medium, fits the multiwavelength observations only moderately well, with a tension between the observed temporal and spectral evolution. This tension is confirmed when using the augmented data set. We find that the consideration of a jet structure (Gaussian or power law), the inclusion of synchrotron self-Compton emission, or the presence of an underlying supernova do not improve the predictions. Placed in the global context of GRB optical afterglows, we find that the afterglow of GRB 221009A is luminous but not extraordinarily so, highlighting that some aspects of this GRB do not deviate from the global known sample despite its extreme energetics and the peculiar afterglow evolution.

2 citations

Journal ArticleDOI
TL;DR: In this paper , the effects of the gamma-ray burst GRB 221009A were studied by electron and proton detectors on board the four spacecraft of the NASA THEMIS mission.
Abstract: We present the first results study of the effects of the powerful gamma-ray burst GRB 221009A that occurred on 2022 October 9, and was serendipitously recorded by electron and proton detectors on board the four spacecraft of the NASA THEMIS mission. Long-duration gamma-ray bursts (GRBs) are powerful cosmic explosions, signaling the death of massive stars, and, among them, GRB 221009A is so far the brightest burst ever observed due to its enormous energy (E γ iso ≈ 1055 erg) and proximity (the redshift is z ≈ 0.1505). The THEMIS mission launched in 2008 was designed to study the plasma processes in the Earth’s magnetosphere and the solar wind. The particle flux measurements from the two inner magnetosphere THEMIS probes, THA and THE, and two outer probes (renamed ARTEMIS after 2010), THB and THC, orbiting the Moon captured the dynamics of GRB 221009A with a high time resolution of 4 (up to 8) measurements per second. This allowed us to resolve the fine structure of the GRB and determine the temporal scales of the two main bursts’ spiky structure, complementing the results from gamma-ray space telescopes and detectors.

1 citations

DOI
28 Jun 2023
TL;DR: In this paper , an algorithm for estimating the availability of 24 kHz channel by assessing the interference level based on spectral monitoring of the HF band to ensure the effective operation of the active time-frequency dispersion sensor is presented.
Abstract: Paper presents an algorithm for estimating the availability of 24 kHz channel by assessing the interference level based on spectral monitoring of the HF band to ensure the effective operation of the active time-frequency dispersion sensor. The effect of narrowband man-made interference rejection on the binary phase shift keying (BPSK) sensor signal was analyzed. Study addressed the energy losses of the BPSK signal with a bandwidth of 24 kHz due to rejection of 3 kHz interferences in its spectrum. There are presented the features of spectral monitoring algorithm in the HF range that provides detection of narrowband interferences, estimation of the availability of channels for efficient sensor operation, as well as experimental verification of the developed algorithms.