相关论文: NuSTAR hard X-ray spectra of radio galaxies
Recent X-ray observations show absorbing winds with velocities up to mildly-relativistic values of the order of ~0.1c in a limited sample of 6 broad-line radio galaxies. They are observed as blue-shifted Fe XXV-XXVI K-shell absorption…
We present Very Large Array observations at 1.4 and 5 GHz of a sample of 16 quasi-stellar objects (QSOs) at z = 1.78 to 2.71. Half of the chosen quasars are bright at mm wavelengths (250 or 350 GHz) while the other half were not detected at…
As part of the GLOSTAR (GLObal view of STAR formation in the Milky Way) survey, we present the high-resolution continuum source catalog for the regions (l = 2-28, 36-40, 56-60, &|b|<1.0), observed with the Karl G. Jansky Very Large Array…
In this paper, we use a highly sensitive telescope to characterize solar X-ray transients ranging from microflares in active regions down to weakly energetic brightenings in the quiet Sun. X-rays are closely linked to the initial energy…
We report MIPS photometry of 20 radio-loud quasars and galaxies at 24 and 70 um (and of five at 160 um). We combine this sample with additional sources detected in the far infrared by IRAS and ISO for a total of 47 objects, including 23…
We present results from a joint Xmm-Newton/NuSTAR monitoring of the Seyfert 1 NGC 4593, consisting of 5x20 ks simultaneous observations spaced by two days, performed in January 2015. The source is variable, both in flux and spectral shape,…
We have used the WGA catalog of ROSAT PSPC X-ray sources to study the X-ray spectrum of about 500 quasars in the redshift interval 0.1--4.1, detected with a signal to noise better than 7. We have parameterized the PSPC spectrum in terms of…
We report on a broadband study of a complex X-ray source (1SAX J0618.0+2227) associated with the interaction site of the supernova remnant (SNR) IC 443 and ambient molecular cloud (MC) using NuSTAR, XMM_Newton, and Chandra observations. Its…
We present two NuSTAR observations of the local Seyfert 2 active galactic nucleus (AGN) and an ultraluminous X-ray source (ULX) candidate in NGC 5643. Together with archival data from Chandra, XMM-Newton and Swift-BAT, we perform a…
Radio galaxies are linearly polarized -- an important property that allows us to infer the properties of the magnetic field of the source and its environment. However at low frequencies, Faraday rotation substantially depolarizes the…
Despite the plethora of deep (sub-mJy) radio surveys there remains considerable doubt as to the exact nature of the galaxies contributing to the source counts. Current evidence suggests that starformation in moderately luminous 'normal'…
We present optical (~3200A to ~9000A) off-nuclear spectra of 26 powerful active galaxies in the redshift range 0.1 < z < 0.3, obtained with the Mayall and William Herschel 4-meter class telescopes. The sample consists of radio-quiet…
Multiwavelength radiation from relativistic particles accelerated at shocks in novae and other astrophysical sources carries a wealth of information about the outflow properties and the microphysical processes at work near the shocks. The…
We present measurement of the cut-off energy, a proxy for the temperature of the corona in the nuclear continuum of the Seyfert 1 galaxy 3C 120 using $\sim$120 ks of observation from ${\it NuSTAR}$. The quality broad band spectrum from…
We present NuSTAR hard X-ray (3-79 keV) observations of three Type 2 quasars at z ~ 0.4-0.5, optically selected from the Sloan Digital Sky Survey (SDSS). Although the quasars show evidence for being heavily obscured Compton-thick systems on…
As part of the GLOSTAR survey we have used the VLA in its B-configuration to observe the part of the Galactic plane between longitudes of 28d and 36d and latitudes from -1d to +1d at the C-band (4--8 GHz). To reduce the contamination of…
The shape of low-frequency radio continuum spectra of normal galaxies is not well understood, the key question being the role of physical processes such as thermal absorption in shaping them. In this work we take advantage of the LOFAR…
We have carried out an analysis of the radio and optical properties of a statistical sample of 45 Seyfert galaxies from the Palomar spectroscopic survey of nearby galaxies. We find that the space density of bright galaxies (-22 mag <=…
XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different emission components of active galactic nuclei (AGNs) and to study the evolution of their different spectral features. In this work, we present the timing and…
More than half of the sources identified by recent radio sky surveys have not been detected by wide-field optical surveys. We present a study based on our co-added image stacking technique, in which our aim is to detect the optical emission…