Prominence Visibility in Hinode/XRT Images

0450549 - ASÚ 2016 RIV US eng J - Journal Article
Schwartz, P. - Jejčič, S. - Heinzel, Petr - Anzer, U. - Jibben, P.R.
Prominence Visibility in Hinode/XRT Images.
Astrophysical Journal. Roč. 807, č. 1 (2015), 97/1-97/9. ISSN 0004-637X. E-ISSN 1538-4357
R&D Projects: GA ČR GAP209/12/0906
Grant - others:SAV(SK) VEGA 2/0108/12
Institutional support: RVO:67985815
Keywords : Sun * corona * Sun filaments
Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Impact factor: 5.909, year: 2015

In this paper we study the soft X-ray. (SXR) signatures of one particular prominence. The X-ray observations used here were made by the Hinode/X-Ray Telescope instrument using two different filters. Both of them have a pronounced peak of the response function around 10 angstrom. One of them has a secondary smaller peak around 170 angstrom, which leads to a contamination of SXR images. The observed darkening in both of these filters has a very large vertical extension. The position and shape of the darkening correspond. nicely with the prominence structure seen in SDO/AIA images. First, we have investigated the possibility that the darkening is caused by X-ray absorption. However, detailed calculations of the optical thickness in this spectral range show clearly that this effect is completely negligible. Therefore, the alternative is the presence of an extended region with a large emissivity deficit, which can be caused by the presence of cool prominence plasmas within an otherwise hot corona. To reproduce the observed darkening, one needs a very large extension along the line. of. sight of the region amounting to around 105 km. We interpret this region as the prominence spine, which is also consistent with SDO/AIA observations in EUV.
Permanent Link: http://hdl.handle.net/11104/0251856