Related papers: Ionization of Infalling Gas
We present a high spatial resolution Halpha survey of 23 cooling flow clusters using the Maryland Magellan Tunable Filter (MMTF), covering 1-2 orders of magnitude in cooling rate, dM/dt, temperature and entropy. We find 8/23 (35%) of our…
We explore the hypothesis that clouds detected in quasar absorption line systems are falling at a terminal velocity toward the center of high redshift gaseous galactic halos. Since both the ionization level and terminal velocity of halo…
We present deep Halpha spectroscopy towards several high-velocity clouds (HVCs) which vary in structure from compact (CHVCs) to the Magellanic Stream. The clouds range from being bright (~640 mR) to having upper limits on the order of 30 to…
The physical properties of galactic halo gas have a profound impact on the life cycle of galaxies. As gas travels through a galactic halo, it undergoes dynamical interactions, influencing its impact on star formation and the chemical…
The Magellanic Stream and several high velocity clouds have now been detected in optical line emission. The observed emission measures and kinematics are most plausibly explained by photoionization due to hot, young stars in the Galactic…
There has been much debate in recent decades as to what fraction of ionizing photons from star forming regions in the Galactic disk escape into the halo. The recent detection of the Magellanic Stream in optical line emission at the CTIO 4m…
We present optical integral field spectroscopy of the H-alpha-luminous (>1E42 erg/s) central cluster galaxies in the cores of the cooling flows A1664, A1835, A2204 and Zw8193. From the [NII]+H-alpha complex we derive 2-D views of the…
In order to determine if the material ablated from high-velocity clouds (HVCs) is a significant source of low-velocity high ions (C IV, N V, and O VI) such as those found in the Galactic halo, we simulate the hydrodynamics of the gas and…
The interaction between inflowing gas clouds and galactic outflows at the interface where the galactic disk transitions into the circumgalactic medium is an important process in galaxy fueling, yet remains poorly understood. Using a series…
We summarize recent attempts to detect warm ionized gas at large galactocentric distances. This includes searching for gas at the edges of spirals, in between cluster galaxies, towards extragalactic HI clouds, and towards high velocity…
We present a new joint analysis of pulsar dispersion measures and diffuse H-alpha emission in the Milky Way, which we use to derive the density, pressure and filling factor of the thick disk component of the warm ionised medium (WIM) as a…
The Warm-Hot Intergalactic Medium (WHIM) is believed to host a significant fraction of the ``missing baryons'' in the nearby Universe. Its signature has been detected in the X-ray absorption spectra of distant quasars. However, its…
In this Letter we demonstrate that the two claims of $z\simeq 0.03$ OVII K$\alpha$ absorption lines from Warm Hot Intergalactic Medium (WHIM) along the lines of sight to the blazars H~2356-309 (Buote et al., 2009; Fang et al., 2010) and…
We study the ionizing sources in spiral galaxies and examine in more detail our Galaxy. Using Taylor & Cordes (1993) model we analyze the electron density in different parts of the Galaxy, and emphasize the still unsolved problems. Finally,…
Using the Wisconsin H-Alpha Mapper (WHAM), we have measured at high spectral resolution and high signal-to-noise the profile of the scattered solar Mg I 5184 absorption line in the zodiacal light. The observations were carried out toward 49…
We have used the Wisconsin H-Alpha Mapper (WHAM) facility to measure the interstellar H-Alpha emission toward the high Galactic latitude O star HD 93521 (l = 183.1, b = +62.2). Three emission components were detected having radial…
We present hydrodynamic simulations of high-velocity clouds (HVCs) traveling through the hot, tenuous medium in the Galactic halo. A suite of models was created using the FLASH hydrodynamics code, sampling various cloud sizes, densities,…
We investigate models for the photoionization of the widespread diffuse ionized gas in galaxies. In particular we address the long standing question of the penetration of Lyman continuum photons from sources close to the galactic midplane…
Spatially extended halos of H I Ly$\alpha$ emission are now ubiquitously found around high-redshift star-forming galaxies. But our understanding of the nature and powering mechanisms of these halos is still hampered by the complex radiative…
We present velocity-resolved maps taken with the Wisconsin H-Alpha Mapper (WHAM) in H{\alpha}, [S II] {\lambda}6716, and [N II] {\lambda}6583 around the well-known O8 III star {\lambda} Ori A (HD 36861) (l = 185{\deg} to 205{\deg}, b =…