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We present a statistical analysis of the Chandra observation of the source field around the 3C 295 galaxy cluster ($z=0.46$). The logN-logS of this field is in good agreement with that computed for the Chandra Deep Field South in this work…

Astrophysics · Physics 2009-11-10 V. D'Elia , F. Fiore , M. Elvis , M. Cappi , S. Mathur , P. Mazzotta , E. Falco

We report on the X-ray emission from the shell-like, non-thermal radio source Sgr A East located in the inner few parsecs of the Galaxy based on observations made with the ACIS detector on board Chandra. This is the first time Sgr A East…

We present SOFIA/upGREAT velocity-resolved spectral imaging and analysis of the 158 um [C II] spectral line toward the central 80 by 43\,pc region of the Central Molecular Zone of the Galaxy. The field we imaged with 14" (0.6 pc) spatial…

Using the 20-pixel camera SHARC, we have surveyed the 350 micron emission from a 60 arcminute by 12 arcminute region in the Galactic center. A comparable region has been observed at 800 microns by Lis & Carlstrom (1994); the SHARC map has…

Astrophysics · Physics 2007-05-23 C. D. Dowell , D. C. Lis , E. Serabyn , M. Gardner , A. Kovacs , S. Yamashita

Suzaku observed a nearby Seyfert 2 galaxy NGC4945, which hosts one of the brightest active galactic nuclei above 20 keV. Combining data from the X-ray CCD camera (XIS) and the Hard X-ray Detector (HXD), the AGN intrinsic nuclear emission…

A powerful outburst of X-ray radiation from the supermassive black hole Sgr A* at the center of the Milky Way is believed to be responsible for the illumination of molecular clouds in the central ~100 pc of the Galaxy (Sunyaev et al., 1993,…

High Energy Astrophysical Phenomena · Physics 2016-12-07 E. Churazov , I. Khabibullin , R. Sunyaev , G. Ponti

The accretion rates needed to fuel the central black hole in a galaxy can be achieved via viscous torques in thick disks and rings, which can be resolved by millimetre interferometry within the inner ~20pc of the active galaxy NGC1068 at…

This paper reports the discovery of evidence for physical contact between the Galactic circumnuclear disk (CND) and an exterior giant molecular cloud. The central 10 pc of our Galaxy has been imaged in the HCN J=1-0, HCO+ J=1-0, CS J=2-1,…

Astrophysics of Galaxies · Physics 2017-01-18 Shunya Takekawa , Tomoharu Oka , Kunihiko Tanaka

Terzan 5, a globular cluster (GC) prominent in mass and population of compact objects, is searched for diffuse X-ray emission, as proposed by several models. We analyzed the data of an archival Chandra observation of Terzan 5 to search for…

High Energy Astrophysical Phenomena · Physics 2015-05-18 P. Eger , W. Domainko , A. -C. Clapson

We present observational evidences that dust in the circumnuclear region of AGNs has different properties than in the Galactic diffuse interstellar medium. By comparing the reddening of optical and infrared broad lines and the X-ray…

Astrophysics · Physics 2009-10-31 R. Maiolino , A. Marconi , M. Salvati , G. Risaliti , P. Severgnini , F. La Franca , L. Vanzi

We investigate the fueling and the feedback of star formation and nuclear activity in NGC1068, a nearby (D=14Mpc) Seyfert 2 barred galaxy, by analyzing the distribution and kinematics of the molecular gas in the disk. We have used ALMA to…

Recent observations of nearby Compton thick (CT) active galactic nuclei (AGNs) with Chandra have resolved hard (>3 keV) X-ray emission extending out from the central supermassive black hole to kiloparsec scales, challenging the long-held…

Astrophysics of Galaxies · Physics 2020-03-25 Mackenzie L. Jones , G. Fabbiano , Martin Elvis , A. Paggi , M. Karovska , W. P. Maksym , A. Siemiginowska , J. Raymond

We examine deep Chandra X-ray observations of the Centaurus cluster of galaxies, Abell 3526. Applying a gradient magnitude filter reveals a wealth of structure, from filamentary soft emission on 100pc (0.5 arcsec) scales close to the…

We use deep archival Chandra and XMM-Newton observations of three of the brightest cluster-centre radio galaxies in the sky, Cygnus A, Hercules A and Hydra A, to search for inverse-Compton emission from the population of electrons…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. J. Hardcastle , J. H. Croston

The highest spectral resolution data for the Fe-K lines in type I AGN, as observed with the Chandra High Energy Grating (HEG), reveal a variety of line shapes. However, the energies of the most prominent peak are all clustered tightly…

Astrophysics · Physics 2007-05-23 T. Yaqoob , U. Padmanabhan

We present a statistical analysis of polarized near-infrared (NIR) light from Sgr A*, the radio source associated with the supermassive black hole at the center of the Milky Way. The observations have been carried out using the adaptive…

Recent measurements of stellar orbits provide compelling evidence that the compact radio source Sagittarius A* at the Galactic Centre is a 3.6-million-solar-mass black hole. Sgr A* is remarkably faint in all wavebands other than the radio…

Astrophysics · Physics 2009-11-10 R. Genzel , R. Schoedel , T. Ott , A. Eckart , T. Alexander , F. Lacombe , D. Rouan , B. Aschenbach

We report the results of high-resolution subpixel imaging of the hard continuum and Fe K{\alpha} line of the Compton Thick (CT) Active Galactic Nucleus (AGN) ESO 428-G014, observed with Chandra ACIS. While the 3-4 keV emission is dominated…

Astrophysics of Galaxies · Physics 2019-01-16 G. Fabbiano , A. Siemiginowska , A. Paggi , M. Elvis , M. Volonteri , L. Mayer , M. Karovska , W. P. Maksym , G. Risaliti , Junfeng Wang

In accretion-based models for Sgr A* the X-ray, infrared, and millimeter emission arise in a hot, geometrically thick accretion flow close to the black hole. The spectrum and size of the source depend on the black hole mass accretion rate…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Monika Moscibrodzka , Hotaka Shiokawa , Charles F. Gammie , Joshua C. Dolence

We discuss the possibility that a dominant fraction of the cosmic rays above the ankle is due to a single nearby source, considering in particular the radio galaxy Centaurus A. We focus on the properties of the source spectrum and…

High Energy Astrophysical Phenomena · Physics 2024-11-28 Silvia Mollerach , Esteban Roulet