1998/11/27 by Yu. A. Shchekinov, Shchekinov, Yu. A.
Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Star Formation Studies #FOS: Physical sciences #Scientific Research and Discoveries #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9811434
21 pages, TeX, Astron. Rept., in press, revision of the paper originally submitted as 9811434, updated references
openalex publication_date 1998/11/27 · arxiv created 1998/12/03 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Possible observational consequences of dark matter in the Galaxy in the form of dense molecular gas clouds - clumpuscules of masses Mc∼ 10-3 \msun and radii Rc∼ 3× 1013 cm - are considered. Recent models of the extreme scattering events - refraction of radio-waves from quasars in dense plasma clumps in the Galactic halo - definitely show on such clouds as possible dark matter candidate. We argue that collisions of such clumpuscules are quite frequent: around 1-10 \msun a year can be ejected in the interstellar medium due to collisions. Optical continuum and 21 cm emissions from post-collisional gas are found to be observable. We show that clumpuscules can form around O stars HII regions of sizes R∼ 30 pc and emission measure EM≃ 20 cm-6 pc, and can also be observable in Hα emission. Evaporation of clumpuscules by external ionizing radiation can be a substantial mass source. From requirement that the total mass input on the Hubble time cannot exceed the luminous mass in the Galaxy, typical radius of clouds is constrained as Rc < 3.5× 1012 cm, and their contribution to surface mass density as 50 \msun pc-2. It is argued that dissipation of kinetic energy of the gas ejected by such clouds can be an efficient energy source for the Galactic halo.