NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-08-18 T00:07:41 PDT
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For refcode 2017ApJ...835..201H:
Retrieve 31 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
2017ApJ...835..201H Thermal Pressure in the Cold Neutral Medium of Nearby Galaxies Herrera-Camus, R.; Bolatto, A.; Wolfire, M.; Ostriker, E.; Draine, B.; Leroy, A.; Sandstrom, K.; Hunt, L.; Kennicutt, R.; Calzetti, D.; Smith, J. D.; Croxall, K.; Galametz, M.; de Looze, I.; Dale, D.; Crocker, A.; Groves, B. Abstract. Dynamic and thermal processes regulate the structure of the multiphase interstellar medium (ISM), and ultimately establish how galaxies evolve through star formation. Thus, to constrain ISM models and better understand the interplay of these processes, it is of great interest to measure the thermal pressure (P_th_) of the diffuse, neutral gas. By combining [C II] 158 micron, H I, and CO data from 31 galaxies selected from the Herschel KINGFISH sample, we have measured thermal pressures in 534 predominantly atomic regions with typical sizes of ~1 kiloparsec. We find a distribution of thermal pressures in the P_th_/k~ 10^3^-10^5^ K cm^-3^ range. For a sub-sample of regions with conditions similar to those of the diffuse, neutral gas in the Galactic plane, we find thermal pressures that follow a log-normal distribution with a median value of P_th_/k ~ 3600 K cm^-3^. These results are consistent with thermal pressure measurements using other observational methods. We find that P_th_ increases with radiation field strength and star formation activity, as expected from the close link between the heating of the gas and the star formation rate. Our thermal pressure measurements fall in the regime where a two-phase ISM with cold and warm neutral media could exist in pressure equilibrium. Finally, we find that the midplane thermal pressure of the diffuse gas is about ~30% of the vertical weight of the overlying ISM, consistent with results from hydrodynamical simulations of self-regulated star formation in galactic disks. Key words: galaxies: ISM, galaxies: star formation, ISM: lines and bands, ISM: structure
Retrieve 31 NED objects in this reference.
Please click here for ADS abstract

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