Abstract
The article considers the poorly studied states of hydrogen gas (called here “quasi-resonant”) with anomalously high intensity ratios of the lines in the Balmer series, \(I({{{\text{H}}}_{\alpha }}){\text{/}}I({{{\text{H}}}_{\beta }})\). It is shown that such states arise in the case of large optical thicknesses of the emitting gas occurring at the frequencies of the Balmer lines, when the gas tends to a thermalization state. The influence on the formation of such states of basic model parameters as temperature, atomic density, and the characteristic size of the emitting region, as well as the presence of external radiation, is studied on simple models. It is shown that quasi-resonant states can exist in the magnetospheres of T Tauri stars at moderate accretion rates.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Notes
Hereinafter, the optical thickness taking into account the velocity gradient is meant.
Ultraviolet and X-ray radiation of accretion spots were not taken into account, since it is absorbed in a very thin layer of a gas falling on the star [12] and does not have a large effect on the intensities of hydrogen lines.
REFERENCES
V. P. Grinin and N. A. Katysheva, Izv. Krymsk. Astrofiz. Observ. 62, 66 (1980).
N. A. Katysheva, T. A. Ermolaeva, and V. P. Grinin, Astrophysics 60, 532 (2017).
D. E. Ostrebrock, Astropysics of Gaseous Nedulae (W. H. Freeman, San Francisco, 1974).
W. E. Kunkel, Astrophys. J. 161, 503 (1970).
R. E. Gershberg and E. E. Shnol’, Izv. Krymsk. Astrofiz. Observ. 50, 122 (1974).
S. A. Drake and R. K. Ulrich, Astrophys. J. Suppl. 42, 351 (1980).
V. V. Sobolev, Sov. Astron. 1, 332 (1957).
G. J. Ferland, R. L. Porter, P. A. M. van Hoof, R. J. R. Williams, et al., Rev. Mex. Astron. Astrofis. 49, 137 (2013).
N. A. Katysheva and V. P. Grinin, in Radiation Mechanisms of Astrophysical Objects: Classics Today, Proceedings of the Conference in Honor of the 100th Birthday of Academician V. V. Sobolev, St. Petersburg, Sept. 21–25, 2015, Ed. by V. P. Grinin, H. Harutyunian, V. B. Ilin, A. F. Kholtygin, and A. Nikoghossian (Edit Print, Erevan, 2017).
L. Hartmann, R. Hewett, and N. Calvet, Astrophys. J. 426, 669 (1994).
D. V. Dmitriev, V. P. Grinin, and N. A. Katysheva, Astron. Lett. 45, 371 (2019).
A. Dodin, Mon. Not. R. Astron. Soc. 475, 4367 (2018).
G. F. Gahm, P. P. Petrov, L. V. Tambovsteva, V. P. Grinin, H. C. Stempels, and F. M. Walter, Astron. Astrophys. 614, A117 (2018).
J. A. Rubino-Martin, J. Chluba, and R. A. Sunyaev, Mon. Not. R. Astron. Soc. 371, 1939 (2006).
M. Soraisam, Ch.-H. Lee, G. Narayan, T. Matheson, et al., Astron. Telegram, No. 12980 (2019).
ACKNOWLEDGMENTS
The authors are grateful to L.V. Tambovtseva and to the referee for useful advices.
Funding
The work of N.A. Katysheva was supported by the development program of the Lomonsov Moscow State University “Leading Scientific Schools: Physics of Stars, Relativistic Objects, and Galaxies.”
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated by E. Chernokozhin
Rights and permissions
About this article
Cite this article
Grinin, V.P., Katysheva, N.A., Ermolaeva, T.A. et al. Quasi-Resonant States of Hydrogen Gas. Astron. Rep. 64, 672–680 (2020). https://doi.org/10.1134/S1063772920090012
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1063772920090012