English

Observational consequences of baryonic gaseous dark matter

Astrophysics 2007-05-23 v3

Abstract

Possible observational consequences of dark matter in the Galaxy in the form of dense molecular gas clouds - clumpuscules of masses Mc103\msunM_c\sim 10^{-3} \msun and radii Rc3×1013R_c\sim 3\times 10^{13} 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 110\msun1-10 \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 R30R\sim 30 pc and emission measure EM20cm6EM\simeq 20 cm^{-6} pc, and can also be observable in HαH_\alpha 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<3.5×1012R_c < 3.5\times 10^{12} cm, and their contribution to surface mass density as 50 \msunpc2\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.

Keywords

Cite

@article{arxiv.astro-ph/9811434,
  title  = {Observational consequences of baryonic gaseous dark matter},
  author = {Yu. A. Shchekinov},
  journal= {arXiv preprint arXiv:astro-ph/9811434},
  year   = {2007}
}

Comments

21 pages, TeX, Astron. Rept., in press, revision of the paper originally submitted as 9811434, updated references