0471836 - ASÚ 2017 RIV FR eng J - Journal Article
Duval, F. - Ostlin, G. - Hayes, M. - Zackrisson, E. - Verhamme, A. - Orlitová, Ivana - Adamo, A. - Guaita, L. - Melinder, J. - Cannon, J.M. - Laursen, P. - Rivera-Thorsen, T. - Herenz, E.Ch. - Gruyters, P. - Mas-Hesse, J. M. - Kunth, D. - Sandberg, A. - Schaerer, D. - Mansson, J.-E.
The Lyman alpha reference sample VI. Lyman alpha escape from the edge-on disk galaxy Mrk 1486.
Astronomy & Astrophysics. Roč. 587, March (2016), A77/1-A77/24. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR(CZ) GP14-20666P
Institutional support: RVO:67985815
Keywords : galaxies * starburst * submillimeter
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 5.014, year: 2016 ; AIS: 1.581, rok: 2016
DOI: https://doi.org/10.1051/0004-6361/201526876

We aim to understand how a strong Ly alpha emission line is able to escape from the low-redshift highly inclined (edge-on) disk galaxy Mrk 1486 (z similar to 0.0338). To our knowledge, this work is the first observational study of Ly alpha transport inside an edge-on disk galaxy.
While a pronounced Ly alpha absorption line emerges from the disk of Mrk 1486, very extended Ly alpha structures are observed at large radii from the galaxy center: a large Ly alpha-halo and two very bright Ly alpha regions located slightly above and below the disk plane. The analysis of IFU H alpha spectroscopic data of Mrk 1486 indicates the presence of two bipolar outflowing halos of HI gas at the same location as these two bright Ly alpha regions. Comparing different diagnostic diagrams (such as [OIII](5007)/H beta versus [OI](6300)/H alpha) to photo-and shock-ionization models, we find that the Ly alpha production of Mrk 1486 is dominated by photoionization inside the galaxy disk. From this perspective, our numerical simulations succeed in reproducing the strength and shape of the observed Ly alpha emission line of Mrk 1486 by assuming a scenario in which the Ly alpha photons are produced inside the galaxy disk, travel along the outflowing halos, and scatter on cool HI materials toward the observer.
Permanent Link: http://hdl.handle.net/11104/0269157