scholarly journals Hard X-ray-to-radio energy distributions in starburst galaxies

1999 ◽  
Vol 193 ◽  
pp. 592-593 ◽  
Author(s):  
Miguel Cerviño ◽  
J. Miguel Mas-Hesse
Keyword(s):  
Energy Distribution ◽  
Mechanical Energy ◽  
Spectral Energy Distribution ◽  
High Energy ◽  
Starburst Galaxies ◽  
Spectral Energy ◽  
X Rays ◽  
X Ray ◽  
High Energy Emission ◽  
X Ray Binaries

We present in this contribution the predictions on the multiwavelength spectral energy distribution of our evolutionary population synthesis models including single and binary stellar systems. The high energy computations include the emission associated to X-ray binaries and supernovae remnants, as well as the mechanical energy released into the interstellar medium, which can be partially reprocessed into thermal X-rays. With these components we compute the spectral energy distribution of starburst galaxies from X-ray to radio ranges, and analyze finally the effects of the high energy emission on the H and He ionizing continuum.

scholarly journals A NuSTAR view of powerful γ-ray loud blazars

2019 ◽  
Vol 627 ◽  
pp. A72 ◽  
Author(s):  
G. Ghisellini ◽  
M. Perri ◽  
L. Costamante ◽  
G. Tagliaferri ◽  
T. Sbarrato ◽  
...  
Keyword(s):  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Peak Frequency ◽  
High Energy ◽  
Spectral Energy ◽  
X Rays ◽  
X Ray ◽  
Γ Ray ◽  
The Universe ◽  
Jet Power

We observed three blazars at z >  2 with the NuSTAR satellite. These were detected in the γ-rays by Fermi/LAT and in the soft X-rays, but have not yet been observed above 10 keV. The flux and slope of their X-ray continuum, together with Fermi/LAT data allows us to estimate their total electromagnetic output and peak frequency. For some of them we were able to study the source in different states, and investigate the main cause of the different observed spectral energy distribution. We then collected all blazars at redshifts greater than 2 observed by NuSTAR, and confirm that these hard and luminous X-ray blazars are among the most powerful persistent sources in the Universe. We confirm the relation between the jet power and the disk luminosity, extending it at the high-energy end.

scholarly journals Tracing the high energy emission of γ-ray detected radio loud quasars

2014 ◽  
Vol 10 (S313) ◽  
pp. 225-230
Author(s):  
Giulia Migliori
Keyword(s):  
Spectral Energy Distribution ◽  
High Energy ◽  
Host Galaxy ◽  
Spectral Energy ◽  
X Ray ◽  
Relativistic Jet ◽  
Quasar Jets ◽  
Γ Ray ◽  
High Energy Emission ◽  
Jet Power

AbstractWe present a multiwavelength study of the core and relativistic jet of the radio loud (RL) quasar RGB J1512+020A (z=0.20). We report the discovery of a bright, 13” extended X-ray jet with a short Chandra observation. We discuss the origin of the jet X-ray emission and its properties in comparison with sample of X-ray quasar jets. The broadband core spectrum is contributed by the emission of the central quasar, by a blazar component, responsible for the γ-ray emission detected by Fermi, and by the host galaxy. We model the non-thermal blazar spectral energy distribution (SED) and constrain the total jet power. The jet power inferred from the blazar SED modeling is in agreement with the values obtained from the total radio power, pointing to a jet that efficiently carries its power up to kiloparsec scales. The quasar emission appears intrinsically weak in the optical-UV band. The disk luminosity estimated from the broad emission lines is lower than the jet power, in agreement with recent results from observations and theory.

scholarly journals Multiwavelength analysis as a probe of accretion and radiative processes in LINERs

2012 ◽  
Vol 8 (S290) ◽  
pp. 355-356
Author(s):  
George Younes ◽  
Delphine Porquet
Keyword(s):  
Black Hole ◽  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Spectral Characteristics ◽  
Spectral Energy ◽  
X Ray ◽  
Radiative Processes ◽  
Central Engine ◽  
Galactic Black Hole ◽  
X Ray Binaries

AbstractWe study the multiwavelength properties of an optically selected sample of Low Ionization Nuclear Emission-line Regions (LINERs), in an attempt to determine the accretion mechanism powering their central engine. We show how their X-ray spectral characteristics, and their spectral energy distribution compare to luminous AGN, and briefly discuss their connection to their less massive counter-parts galactic black-hole X-ray binaries.

scholarly journals Centaurus A at Hard X-Rays and Soft Gamma-Rays

2010 ◽  
Vol 27 (4) ◽  
pp. 431-438 ◽  
Author(s):  
H. Steinle
Keyword(s):  
Energy Range ◽  
Spatial Resolution ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Spectral Energy Distribution ◽  
High Energy ◽  
Spectral Energy ◽  
X Rays ◽  
Satellite Mission ◽  
X Ray

AbstractCen A, at a distance of less than 4 Mpc, is the nearest radio-loud AGN. Its emission is detected from radio to very-high energy gamma-rays. Despite the fact that Cen A is one of the best studied extragalactic objects the origin of its hard X-ray and soft gamma-ray emission (100 keV <E< 50 MeV) is still uncertain. Observations with high spatial resolution in the adjacent soft X-ray and hard gamma-ray regimes suggest that several distinct components such as a Seyfert-like nucleus, relativistic jets, and even luminous X-ray binaries within Cen A may contribute to the total emission in the MeV regime that has been detected with low spatial resolution. As the Spectral Energy Distribution of Cen A has its second maximum around 1 MeV, this energy range plays an important role in modeling the emission of (this) AGN. As there will be no satellite mission in the near future that will cover this energies with higher spatial resolution and better sensitivity, an overview of all existing hard X-ray and soft gamma-ray measurements of Cen A is presented here defining the present knowledge on Cen A in the MeV energy range.

scholarly journals IGR J17503–2636: a candidate supergiant fast X-ray transient

2019 ◽  
Vol 624 ◽  
pp. A142 ◽  
Author(s):  
C. Ferrigno ◽  
E. Bozzo ◽  
A. Sanna ◽  
G. K. Jaisawal ◽  
J. M. Girard ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
Neutron Star ◽  
Energy Distribution ◽  
Power Law ◽  
Spectral Energy Distribution ◽  
High Energy ◽  
Spectral Energy ◽  
X Ray ◽  
Broad Feature

The object IGR J17503–2636 is a hard X-ray transient discovered by INTEGRAL on 2018 August 11. This was the first ever reported X-ray emission from this source. Following the discovery, follow-up observations were carried out with Swift, Chandra, NICER, and NuSTAR. Here we report on the analysis of all of these X-ray data and the results obtained. Based on the fast variability in the X-ray domain, the spectral energy distribution in the 0.5–80 keV energy range, and the reported association with a highly reddened OB supergiant at ∼10 kpc, we conclude that IGR J17503–2636 is most likely a relatively faint new member of the supergiant fast X-ray transients. Spectral analysis of the NuSTAR data revealed a broad feature in addition to the typical power-law with exponential roll-over at high energy. This can be modeled either in emission or as a cyclotron scattering feature in absorption. If confirmed by future observations, this feature would indicate that IGR J17503–2636 hosts a strongly magnetized neutron star with B ∼ 2 × 1012 G.

scholarly journals The Spectral Energy Distribution of Quiescent Black Hole X‐Ray Binaries: New Constraints fromSpitzer

2007 ◽  
Vol 670 (1) ◽  
pp. 600-609 ◽  
Author(s):  
Elena Gallo ◽  
Simone Migliari ◽  
Sera Markoff ◽  
John A. Tomsick ◽  
Charles D. Bailyn ◽  
...  
Keyword(s):  
Black Hole ◽  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Spectral Energy ◽  
X Ray ◽  
X Ray Binaries

scholarly journals A new hard X-ray-selected sample of extreme high-energy peaked BL Lac objects and their TeV gamma-ray properties

2019 ◽  
Vol 486 (2) ◽  
pp. 1741-1762 ◽  
Author(s):  
L Foffano ◽  
E Prandini ◽  
A Franceschini ◽  
S Paiano
Keyword(s):  
Spectral Properties ◽  
Gamma Ray ◽  
Spectral Energy Distribution ◽  
Broad Band ◽  
High Energy ◽  
Spectral Energy ◽  
X Rays ◽  
Bl Lac Objects ◽  
X Ray ◽  
Bl Lac

ABSTRACT Extreme high-energy peaked BL Lac objects (EHBLs) are an emerging class of blazars with exceptional spectral properties. The non-thermal emission of the relativistic jet peaks in the spectral energy distribution (SED) plot with the synchrotron emission in X-rays and with the gamma-ray emission in the TeV range or above. These high photon energies may represent a challenge for the standard modelling of these sources. They are important for the implications on the indirect measurements of the extragalactic background light, the intergalactic magnetic field estimate, and the possible origin of extragalactic high-energy neutrinos. In this paper, we perform a comparative study of the multiwavelength spectra of 32 EHBL objects detected by the Swift-BAT telescope in the hard X-ray band and by the Fermi-LAT telescope in the high-energy gamma-ray band. The source sample presents uniform spectral properties in the broad-band SEDs, except for the TeV gamma-ray band where an interesting bimodality seems to emerge. This suggests that the EHBL class is not homogeneous, and a possible subclassification of the EHBLs may be unveiled. Furthermore, in order to increase the number of EHBLs and settle their statistics, we discuss the potential detectability of the 14 currently TeV gamma-ray undetected sources in our sample by the Cherenkov telescopes.

scholarly journals Multiwavelength data for bright active galaxies

2011 ◽  
Vol 7 (S284) ◽  
pp. 237-239
Author(s):  
Areg M. Mickaelian ◽  
Hayk V. Abrahamyan ◽  
Gurgen M. Paronyan ◽  
Gohar S. Harutyunyan
Keyword(s):  
Energy Distribution ◽  
Spectral Energy Distribution ◽  
Active Galaxies ◽  
Photometric Data ◽  
Spectral Energy ◽  
X Rays ◽  
Large Area ◽  
X Ray ◽  
Space Objects ◽  
Cross Correlations

AbstractThe spectral energy distribution (SED) gives a complete picture of the radiation of space objects and may result in correct classifications compared to those based only on optical (or other local) spectra. This is especially crucial for active galaxies, both AGN and Starbursts (SB). For this, multiwavelength (MW) data are needed taken from available surveys and catalogs. We have cross-correlated the Catalogue of quasars and active galaxies with all-sky or large-area MW catalogues, such as X-ray ROSAT (BSC and FSC), UV GALEX (MIS and AIS), optical APM, MAPS, USNO-B1.0, GSC 2.3.2, and SDSS DR8, NIR 2MASS, MIR/FIR WISE, IRAS (PSC and FSC) and AKARI (IRC and FIS), radio GB6, NVSS, FIRST, and WENSS. We have established accurate positions and photometry for a few thousands of objects that appeared in the catalog with poor data, as well as achieved the best astrometric and photometric data for all objects. This allowed correct cross-correlations and establishing correct MW data for these objects. As a result, we obtained 34 photometric points from X-rays to radio and using VO tools built SEDs for some 10,000 bright objects. Some data from other surveys were also used, such as Chandra, XMM, Spitzer, etc. All objects were grouped into several forms of SED and were compared to the known optical classes given in the catalog (QSO, BLL, Sy1, Sy1.2–1.9, Sy2, LINER, SB, and HII). This allowed reveal obscured AGN, as well as find previously misclassified objects. A homogeneous classification for these objects was established. The first part of this project is presented; establishment of accurate positions and photometry and cross-correlations with MW catalogs.

Sign in / Sign up

Export Citation Format

Share Document