Počet záznamů: 1
Brightness Temperature of Radio Zebras and Wave Energy Densities in Their Sources
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SYSNO ASEP 0482456 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Brightness Temperature of Radio Zebras and Wave Energy Densities in Their Sources Tvůrce(i) Yasnov, L. V. (RU)
Benáček, J. (CZ)
Karlický, Marian (ASU-R) RID, ORCIDZdroj.dok. Solar Physics. - : Springer - ISSN 0038-0938
Roč. 292, č. 11 (2017), 163/1-163/12Poč.str. 12 s. Forma vydání Tištěná - P Jazyk dok. eng - angličtina Země vyd. NL - Nizozemsko Klíč. slova Sun corona ; Su flares ; radio radiation Vědní obor RIV BN - Astronomie a nebeská mechanika, astrofyzika Obor OECD Astronomy (including astrophysics,space science) CEP GA16-13277S GA ČR - Grantová agentura ČR GA17-16447S GA ČR - Grantová agentura ČR Institucionální podpora ASU-R - RVO:67985815 UT WOS 000413851500001 EID SCOPUS 85032365353 DOI 10.1007/s11207-017-1174-4 Anotace We estimated the brightness temperature of radio zebras (zebra pattern - ZP), considering that ZPs are generated in loops having an exponential density profile in their cross section. We took into account that when in a plasma there is a source emitting in all directions, then in the escape process from the plasma the emission has a directional character nearly perpendicular to the constant-density profile. Owing to the high directivity of the plasma emission (for emission at frequencies close to the plasma frequency), the region from which the emission escapes can be very small. We estimated the brightness temperature of three observed ZPs for two values of the density scale height (1 and 0.21 Mm) and two values of the loop width (1 and 2 arcsec). In all cases, high brightness temperatures were obtained. For the higher value of the density scale height, the brightness temperature was estimated to be 1.1 x 10(15) -1.3 x 10(17) K, and for the lower value, it was 4.7 x 10(13) - 5.6 x 10(15) K. These temperatures show that the observational probability of a burst with a ZP, which is generated in the transition region with a steep gradient of the plasma density, is significantly higher than for a burst generated in a region with smoother changes of the plasma density. Pracoviště Astronomický ústav Kontakt Radka Svašková, bibl@asu.cas.cz, Tel.: 323 620 326 Rok sběru 2018
Počet záznamů: 1