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Using data from the DEEP2 galaxy redshift survey and the All Wavelength Extended Groth Strip International Survey we obtain stacked X-ray maps of galaxies at 0.7 < z < 1.0 as a function of stellar mass. We compute the total X-ray counts of these gala xies and show that in the soft band (0.5--2,kev) there exists a significant correlation between galaxy X-ray counts and stellar mass at these redshifts. The best-fit relation between X-ray counts and stellar mass can be characterized by a power law with a slope of 0.58 +/- 0.1. We do not find any correlation between stellar mass and X-ray luminosities in the hard (2--7,kev) and ultra-hard (4--7,kev) bands. The derived hardness ratios of our galaxies suggest that the X-ray emission is degenerate between two spectral models, namely point-like power-law emission and extended plasma emission in the interstellar medium. This is similar to what has been observed in low redshift galaxies. Using a simple spectral model where half of the emission comes from power-law sources and the other half from the extended hot halo we derive the X-ray luminosities of our galaxies. The soft X-ray luminosities of our galaxies lie in the range 10^39-8x10^40, ergs/s. Dividing our galaxy sample by the criteria U-B > 1, we find no evidence that our results for X-ray scaling relations depend on optical color.
Using data from the All Wavelength Extended Groth Strip International Survey (AEGIS) we statistically detect the extended X-ray emission in the interstellar medium (ISM)/intra-cluster medium (ICM) in both active and normal galaxies at 0.3 <= z <= 1.3 . For both active galactic nuclei (AGN) host galaxy and normal galaxy samples that are matched in restframe color, luminosity, and redshift distribution, we tentatively detect excess X-ray emission at scales of 1--10 arcsec at a few sigma significance in the surface brightness profiles. The exact significance of this detection is sensitive to the true characterization of Chandras point spread function. The observed excess in the surface brightness profiles is suggestive of lower extended emission in AGN hosts compared to normal galaxies. This is qualitatively similar to theoretical predictions of the X-ray surface brightness profile from AGN feedback models, where feedback from AGN is likely to evacuate the gas from the center of the galaxy/cluster. We propose that AGN that are intrinsically under-luminous in X-rays, but have equivalent bolometric luminosities to our sources will be the ideal sample to study more robustly the effect of AGN feedback on diffuse ISM/ICM gas.
Quasar feedback has most likely a substantial but only partially understood impact on the formation of structure in the universe. A potential direct probe of this feedback mechanism is the Sunyaev-Zeldovich effect: energy emitted from quasar heats th e surrounding intergalactic medium and induce a distortion in the microwave background radiation passing through the region. Here we examine the formation of such hot quasar bubbles using a cosmological hydrodynamic simulation which includes a self-consistent treatment of black hole growth and associated feedback, along with radiative gas cooling and star formation. From this simulation, we construct microwave maps of the resulting Sunyaev-Zeldovich effect around black holes with a range of masses and redshifts. The size of the temperature distortion scales approximately with black hole mass and accretion rate, with a typical amplitude up to a few micro-Kelvin on angular scales around 10 arcseconds. We discuss prospects for the direct detection of this signal with current and future single-dish and interferometric observations, including ALMA and CCAT. These measurements will be challenging, but will allow us to characterize the evolution and growth of supermassive black holes and the role of their energy feedback on galaxy formation.
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