Астрофизический семинар ИНАСАН № 253 (1 июля 2013 г., 11:00)Опубликовано: 01/07/2013
Докладчик: Креловский Я. (Торуньский астрономический центр Университета Н. Коперника, Польша)
Название доклада: “Корреляции и семейства диффузных межзвёздных полос”
Краткое содержание доклада:
The term “Families of diffuse bands” appeared in 1986/87 when we found with my collaborators: Gordon A.H. Walker and Bengt E. Westerlund that the strength ratio of the major DIBs 5780 and 5797 is heavily variable. We proved that at the same E(B-V) the DIB intensities may vary as much as by a factor of 3 or more. A similar result was published by Josafatsson and Snow. A decade later, we proposed (with Chris Sneden) that certain DIB strength ratios seem to be related to intensities of the known features of simple molecular species; this led to the introduction of the so called sigma and zeta type interstellar clouds. The former are characterized by very weak molecular features while the latter – by rather strong. Currently we face a bunch of questions: are the DIB intensities related to those of certain molecular species, e.g. C2 as suggested by the group of Hobbs and Snow? Do the DIB profiles, found as complex by Peter Sarre, depend on e.g. rotational temperatures of simple, linear carbon species? Do the DIB profiles depend on the irradiation of interstellar clouds by nearby stars? The relative DIB strengths as well as those of the simple radicals seem to be related to the shapes of interstellar extinction curves. We face thus three players in the interstellar space: dust particles, simple radicals and the DIB carriers. Apparently their mutual relations depend on local physical parameters of the intervening clouds.