Izvestiya Krymskoi Astrofizicheskoi Observatorii https://jn.craocrimea.ru/index.php/izvcrao <p><em>Izvestiya Krymskoi Astrofizicheskoi Observatorii</em> publishes original papers on observational and theoretical astrophysics, and related topics in geophysics and solar physics. Papers on ground-based and space-based astrophysical instrumentation, invited reviews, and conference proceedings are also included. The journal <em>Izvestiya Krymskoi Astrofizicheskoi Observatorii</em> was founded in 1947.</p> en-US <div class="value">Copyright and publishing rights for texts published in Izvestiya Krymskoi Astrofizicheskoi Observatorii is retained by the authors, with first publication rights granted to the journal.Texts are free to use with proper attribution and link to the licensing (<a href="http://creativecommons.org/licenses/by/4.0/" rel="license">Creative Commons Attribution 4.0 International).</a><br><br><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img style="border-width: 0;" src="https://i.creativecommons.org/l/by/4.0/88x31.png" alt="Creative Commons License"></a></div> baklanov@craocrimea.ru (Редакция журнала) journal@craocrimea.ru (Техническая поддержка) Mon, 23 Dec 2019 03:19:09 +0300 OJS 3.1.2.4 http://blogs.law.harvard.edu/tech/rss 60 Magnetic power spectrum in the undisturbed solar photosphere https://jn.craocrimea.ru/index.php/izvcrao/article/view/663 <p>Using the magnetic field data obtained with the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO), an investigation of magnetic power spectra in the undisturbed solar photosphere was performed. The results are as follows. 1) To get a reliable estimate of a magnetic power spectrum from the uniformly distributed quiet-sun magnetic flux, a sample pattern of no less than 300 pixels length should be adopted. With smaller patterns, energy on all observable scales might be overestimated. 2) For patterns of different magnetic intensity (e.g., a coronal hole, a quiet-sun area, an area of supergranulation), the magnetic power spectra in a range of (2.5-10) Mm exhibit very close spectral indices of about -1. The observed spectrum is more shallow than the Kolmogorov-type spectrum (with a slope of -5/3) and it differs from steep spectra of active regions. Such a shallow spectrum cannot be explained by the only direct Kolmogorov’s cascade, but it can imply a small-scale turbulent dynamo action in a wide range of scales: from tens of megameters down to at least 2.5 Mm. On smaller scales, the HMI/SDO data do not allow us to reliably derive the shape of the spectrum. 3) Data make it possible to conclude that a uniform mechanism of the small-scale turbulent dynamo is at work all over the solar surface outside active regions.</p> Valentina Abramenko, Olga Kutsenko Copyright (c) 2019 Valentina Abramenko, Ol'ga Kutsenko https://jn.craocrimea.ru/index.php/izvcrao/article/view/663 Fri, 20 Dec 2019 00:00:00 +0300 Dynamic processes in an active region in the initial and impulsive phase of the eruptive flare event on june 7, 2011 https://jn.craocrimea.ru/index.php/izvcrao/article/view/656 <p>We present the results of an analysis of H<sub>α</sub> monochromatic and spectral observations of an impressive filament eruption during the eruptive flare on June 7, 2011 obtained at the Crimean Astrophysical Observatory. Our ground-based observations are combined with data acquired by multiple instruments onboard the Solar Dynamics Observatory (SDO/AIA, SDO/HMI). The evolution and dynamics of the eruptive process, the cause of eruption, the structure of the line-of-sight velocity field and fine internal structure of the eruptive filament are studied and a number of physical parameters in the eruptive filament are determined. <br>The results of the analysis have shown that: 1) The evolution of the filament eruption consists of two phases: the slow-rise phase, which began about two hours before the flare onset, and the fast-rise phase, which began almost simultaneously with the start of the flare. 2) The eruptive filament had a very complex internal structure and complicated line-of-sight velocity field. The filament does not erupt as a single structure. Several discrete massive absorption fragments are seen with a large number of fine-structured elements inside fragments with different velocities, as well as many plasma blobs that detach from the fragments. 3) The movement of the filament fragments is a combination of rotational movement around the axis of the main fragment and a bulk motion towards the observer as they erupt. The velocities of such plasma movements are determined. 4) H<sub>α</sub> line profiles show a large variety of contrast values, Doppler half-widths and Doppler shifts in eruptive filament elements.</p> Artur Babin, Aleksandra Koval' Copyright (c) 2019 Artur Babin, Aleksandra Koval' https://jn.craocrimea.ru/index.php/izvcrao/article/view/656 Mon, 23 Dec 2019 00:00:00 +0300 Observation of the exoplanetary transit for Wasp-2 https://jn.craocrimea.ru/index.php/izvcrao/article/view/657 <p>We present observations of the transit of an exoplanet from the WASP-2 star carried out with the MTM-500 telescope at the Crimean Astrophysical Observatory of the Russian Academy of Sciences. A brief history of the discovery of exoplanet WASP-2b is considered. The main characteristics are outlined. The observations and a processing procedure are described. Analysis of the obtained results was performed and compared with information from the ETD and NASA Exoplanet Archive databases. The photometry data of the WASP-2 star and the comparison star GSC 0052201406 are given in Appendix to the article.</p> Vladimir Ignatov, Mark Gorbachev, Aleksei Shlyapnikov Copyright (c) 2019 Vladimir Ignatov, Mark Gorbachev, Aleksei Shlyapnikov https://jn.craocrimea.ru/index.php/izvcrao/article/view/657 Mon, 23 Dec 2019 00:00:00 +0300 Stars from the GTSh10 catalog in the Shajn’s Plan https://jn.craocrimea.ru/index.php/izvcrao/article/view/658 <p>We examine objects from the GTSh10 catalog among the studied stars as a part of implementing the Plan of Academician G.A. Shajn in order to replenish the database of photometric and spectral observations of red dwarfs. We consider a question concerning the cross-identification of data from the GTSh10 interactive version and the&nbsp; Shajn's Plan&nbsp; catalogs, as well as an access to the archive of photographic observations. The article is illustrated with examples of working with the obtained list by means of the Virtual Observatory in order to analyze the state of objects and/or to refine their photometric and spectral characteristics in the middle of the past century.</p> Maksim Gorbunov, Aleksei Shlyapnikov Copyright (c) 2019 Maksim Gorbunov, Aleksei Shlyapnikov https://jn.craocrimea.ru/index.php/izvcrao/article/view/658 Mon, 23 Dec 2019 00:00:00 +0300 Archives of CrAO spectral observations. Catalogs of objects and images https://jn.craocrimea.ru/index.php/izvcrao/article/view/660 <p>The work described in this article is a continuation of the previously initiated research on archival spectral observations carried out in Crimea. It covers a time interval of about 90 years and contains information about spectroscopy using various facilities: from the wide-angle astrographs with an objective prism to the main CrAO telescope - ZTSh. A brief history of telescopes and their equipment is presented. The article is illustrated with possibilities of a network access to the catalogs of observations taken with various instruments in the interactive Aladin Sky Atlas with the redirection to original spectrograms. To this aim, the linear coordinates of scanned negatives were converted into a scale which corresponds to the wavelengths. The possibilities of taking into account the spectral sensitivity of the recorded images by the absolute energy distribution are shown. A feature of this work is the connection of digitized original observations and results of their independent processing with the data published for objects in the&nbsp; Izvestiya Krymskoi Astrofizicheskoi Observatorii.</p> Aleksei Shlyapnikov, Maksim Gorbunov, Mark Gоrbachev, Ruslan Akmetdinov Copyright (c) 2019 Aleksei Shlyapnikov, Maksim Gorbunov, Mark Gorbachev, Ruslan Akmetdinov https://jn.craocrimea.ru/index.php/izvcrao/article/view/660 Mon, 23 Dec 2019 00:00:00 +0300 On the Magnetic Skeleton of Solar and Stellar Coronae or About Possibility of Coronal Loop Formation by the Mechanical Pinch Effect https://jn.craocrimea.ru/index.php/izvcrao/article/view/662 <p>It is shown that the mechanical pinch can be responsible for the loop structure of solar and stellar coronae.</p> Roal'd Gershberg Copyright (c) 2019 Roal'd Gershberg https://jn.craocrimea.ru/index.php/izvcrao/article/view/662 Mon, 23 Dec 2019 00:00:00 +0300 Echelle spectrograph of the 2.6-meter Shajn telescope https://jn.craocrimea.ru/index.php/izvcrao/article/view/659 <p>The paper describes the high resolution echelle spectrograph ESPL developed for the coude focus of the 2.6 m Shajn reflector of the Сrimean Astrophysical Observatory.&nbsp; The spectrograph has been regularly operated since 2013. Efficiency of the spectrograph is estimated from observations of stars.</p> Aleksandr Lagutin, Sergei Plachinda, Dmitrii Shakhovskoi, Evgenii Nekhai, Dilyara Baklanova, Petr Petrov Copyright (c) 2019 Aleksandr Lagutin et al. https://jn.craocrimea.ru/index.php/izvcrao/article/view/659 Mon, 23 Dec 2019 00:00:00 +0300 UBVRI photometric system of the meniscus telescope MTM-500 https://jn.craocrimea.ru/index.php/izvcrao/article/view/661 <p>We present the method and results of defining coefficients while passing on from the instrument brightness values in u, b, v, r, i bands to U, B, V, R, I bands of the Johnson - Cousins system at the telescope MTM-500.</p> Aleksei Rublevskii, Nikolai Kiselev Copyright (c) 2019 Aleksei Rublevskii, Nikolai Kiselev https://jn.craocrimea.ru/index.php/izvcrao/article/view/661 Mon, 23 Dec 2019 00:00:00 +0300