%0 Generic %1 faerman2016massive %A Faerman, Yakov %A Sternberg, Amiel %A McKee, Christopher F. %D 2016 %K coronae hot model warm %T Massive Warm/Hot Galaxy Coronae as Probed by OVI, OVII and OVIII Absorbers %U http://arxiv.org/abs/1602.00689 %X We construct an analytic phenomenological model for extended warm/hot gaseous coronae of L* galaxies. We aim to reproduce the column densities of highly ionized oxygen ions observed in the ultraviolet and X-ray, as evidence for warm/hot gas in a wide range of temperatures and ionization states. We consider OVI data from the COS-Halos sample of galaxies in combination with the nearby OVII and OVIII absorption that we interpret as arising in an extended corona around the Milky Way. We fit these data sets with a single representative model. The gas in our model is multiphased, with hot and warm components. Each component has a (turbulent) log-normal distribution of temperatures and densities. The hot gas is traced by the OVII and OVIII and is in hydrostatic equilibrium in a Milky Way gravitational potential. The median temperature of the hot gas is $1.8*10^6$ K and the resulting mean hydrogen density is $\sim 5*10^-5~cm^-3$, consistent with ram-pressure stripping observed in Milky Way satellites. The warm component is traced by the OVI as seen in absorption around the external galaxies. The corona in our model is a large structure, extending slightly beyond the virial radius. The total warm/hot gas mass is high and is $1.35*10^11~M_ødot$. The gas metallicity we require to reproduce the oxygen ion column densities is 0.5 solar. Lower values lead to higher gas masses, and too many baryons, given the virial mass of the Milky Way. The warm OVI component has a short cooling time ($<10^8$ years), as hinted by observations. The hot component, however, is $90\%$ of the total gas mass and is long-lived, with $t_cool 2*10^10$ years. Our model suggests that hot coronae of galaxies can contain significant amounts of gas, enabling galaxies to continue forming stars steadily for long periods of time and also accounting for "missing baryons" in galaxies in the local universe.

@misc{faerman2016massive, abstract = {We construct an analytic phenomenological model for extended warm/hot gaseous coronae of L* galaxies. We aim to reproduce the column densities of highly ionized oxygen ions observed in the ultraviolet and X-ray, as evidence for warm/hot gas in a wide range of temperatures and ionization states. We consider OVI data from the COS-Halos sample of galaxies in combination with the nearby OVII and OVIII absorption that we interpret as arising in an extended corona around the Milky Way. We fit these data sets with a single representative model. The gas in our model is multiphased, with hot and warm components. Each component has a (turbulent) log-normal distribution of temperatures and densities. The hot gas is traced by the OVII and OVIII and is in hydrostatic equilibrium in a Milky Way gravitational potential. The median temperature of the hot gas is $1.8*10^6$ K and the resulting mean hydrogen density is $\sim 5*10^{-5}~cm^{-3}$, consistent with ram-pressure stripping observed in Milky Way satellites. The warm component is traced by the OVI as seen in absorption around the external galaxies. The corona in our model is a large structure, extending slightly beyond the virial radius. The total warm/hot gas mass is high and is $1.35*10^{11}~M_{\odot}$. The gas metallicity we require to reproduce the oxygen ion column densities is 0.5 solar. Lower values lead to higher gas masses, and too many baryons, given the virial mass of the Milky Way. The warm OVI component has a short cooling time ($<10^8$ years), as hinted by observations. The hot component, however, is $\sim 90\%$ of the total gas mass and is long-lived, with $t_{\rm cool} \sim 2*10^{10}$ years. Our model suggests that hot coronae of galaxies can contain significant amounts of gas, enabling galaxies to continue forming stars steadily for long periods of time and also accounting for "missing baryons" in galaxies in the local universe.}, added-at = {2016-02-03T10:01:57.000+0100}, author = {Faerman, Yakov and Sternberg, Amiel and McKee, Christopher F.}, biburl = {https://www.bibsonomy.org/bibtex/24cb7bb2df2fbd2b5b8469cca3748f7a5/miki}, description = {[1602.00689] Massive Warm/Hot Galaxy Coronae as Probed by OVI, OVII and OVIII Absorbers}, interhash = {922fa6f698c5080beb591a10b05b10bb}, intrahash = {4cb7bb2df2fbd2b5b8469cca3748f7a5}, keywords = {coronae hot model warm}, note = {cite arxiv:1602.00689Comment: 13 pages, 5 figures. Submitted to ApJ, comments welcome}, timestamp = {2016-02-03T10:01:57.000+0100}, title = {Massive Warm/Hot Galaxy Coronae as Probed by OVI, OVII and OVIII Absorbers}, url = {http://arxiv.org/abs/1602.00689}, year = 2016 }