%0 Generic %1 nicastro2016distant %A Nicastro, F. %A Senatore, F. %A Krongold, Y. %A Mathur, S. %A Elvis, M. %D 2016 %K baryon census cgm milky way %T A Distant Echo of Milky Way Central Activity closes the Galaxy's Baryon Census %U http://arxiv.org/abs/1604.08210 %X We report on the presence of large amounts of million-degree gas in the Milky Way's interstellar and circum-galactic medium. This gas (1) permeates both the Galactic plane and the halo, (2) extends to distances larger than 60-200 kpc from the center, and (3) its mass is sufficient to close the Galaxy's baryon census. Moreover, we show that a vast, $6$ kpc radius, spherically-symmetric central region of the Milky Way above and below the 0.16 kpc thick plane, has either been emptied of hot gas or the density of this gas within the cavity has a peculiar profile, increasing from the center up to a radius of $6$ kpc, and then decreasing with a typical halo density profile. This, and several other converging pieces of evidence, suggest that the current surface of the cavity, at 6 kpc from the Galaxy's center, traces the distant echo of a period of strong nuclear activity of our super-massive black-hole, occurred about 6 Myrs ago.

@misc{nicastro2016distant, abstract = {We report on the presence of large amounts of million-degree gas in the Milky Way's interstellar and circum-galactic medium. This gas (1) permeates both the Galactic plane and the halo, (2) extends to distances larger than 60-200 kpc from the center, and (3) its mass is sufficient to close the Galaxy's baryon census. Moreover, we show that a vast, $\sim 6$ kpc radius, spherically-symmetric central region of the Milky Way above and below the 0.16 kpc thick plane, has either been emptied of hot gas or the density of this gas within the cavity has a peculiar profile, increasing from the center up to a radius of $\sim 6$ kpc, and then decreasing with a typical halo density profile. This, and several other converging pieces of evidence, suggest that the current surface of the cavity, at 6 kpc from the Galaxy's center, traces the distant echo of a period of strong nuclear activity of our super-massive black-hole, occurred about 6 Myrs ago.}, added-at = {2016-04-29T09:45:27.000+0200}, author = {Nicastro, F. and Senatore, F. and Krongold, Y. and Mathur, S. and Elvis, M.}, biburl = {https://www.bibsonomy.org/bibtex/2077b419c54bb0dd2a83a2eda9e793e09/miki}, description = {[1604.08210] A Distant Echo of Milky Way Central Activity closes the Galaxy's Baryon Census}, interhash = {16e53675bd7a0bca99e9e88c21c3f394}, intrahash = {077b419c54bb0dd2a83a2eda9e793e09}, keywords = {baryon census cgm milky way}, note = {cite arxiv:1604.08210Comment: 19 pages, 3 Figures; Submitted to the ApJL}, timestamp = {2016-04-29T09:45:27.000+0200}, title = {A Distant Echo of Milky Way Central Activity closes the Galaxy's Baryon Census}, url = {http://arxiv.org/abs/1604.08210}, year = 2016 }