English
Related papers

Related papers: BAT X-ray Survey - I: Methodology and X-ray Identi…

200 papers

In preparation for GLAST, we have compiled a sample of blazar candidates to increase the pool of well studied AGN from which GLAST counterparts will be drawn. Sources were selected with our Figure of Merit (FoM) ranking; thus, they have…

Our present knowledge of the properties of blazars mostly comes from small samples of bright objects, especially regarding studies on their cosmological evolution. Statistically well defined and completely identified samples of faint…

High Energy Astrophysical Phenomena · Physics 2019-09-04 Sara Turriziani , Bernardo Fraga , Paolo Giommi

Forthcoming astronomical surveys are expected to detect new sources in such large numbers that measuring their spectroscopic redshift measurements will be not be practical. Thus, there is much interest in using machine learning to yield the…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 S. J. Curran

Microquasars are ideal natural laboratories for understanding accretion/ejection processes, studying the physics of relativistic jets, and testing gravitational phenomena. Nevertheless, these objects are difficult to find in our Galaxy. The…

Astrophysics · Physics 2009-11-13 J. A. Combi , J. F. Albacete-Colombo , J. Marti

Following the presentation of the XMM-LSS X-ray source detection package by Pacaud et al., we provide the source lists for the first 5.5 surveyed square degrees. The catalogues pertain to the [0.5-2] and [2-10] keV bands and contain in…

EGRET data are usually analysed on the basis of the Maximum-Likelihood method \cite{ma96} in a search for point sources in excess to a model for the background radiation (e.g. \cite{hu97}). This method depends strongly on the quality of the…

Astrophysics · Physics 2009-10-30 Martin Pohl

Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 M. Ajello , D. M. Alexander , J. Greiner , G. M. Madejski , N. Gehrels , D. Burlon

We searched for X-ray serendipitous sources in over 370 Swift-XRT fields centered on gamma ray bursts detected between 2004 and 2008 and observed with total exposures ranging from 10 ks to over 1 Ms. This defines the Swift Serendipitous…

We develop a new estimation technique for recovering depth-of-field from multiple stereo images. Depth-of-field is estimated by determining the shift in image location resulting from different camera viewpoints. When this shift is not…

Applications · Statistics 2009-10-07 E. Anderes , B. Yu , V. Jovanovic , C. Moroney , M. Garay , A. Braverman , E. Clothiaux

We present the ROSAT All-Sky Survey Bright Source Catalogue (RASS-BSC, revision 1RXS) derived from the all-sky survey performed during the first half year (1990/91) of the ROSAT mission. 18,811 sources are catalogued (i) down to a limiting…

Recent X-ray surveys have now resolved most of the X-ray background (XRB) into discrete sources. While this represents a break- through in the understanding of the XRB, the astrophysical nature of these sources still remains mysterious. In…

Astrophysics · Physics 2007-05-23 J. Zuther , A. Eckart , W. Voges , C. Straubmeier

The wavelet detection algorithm (WDA) described in the accompanying paper by Lazzati et al. is made suited for a fast and efficient analysis of images taken with the High Resolution Imager (HRI) instrument on board the ROSAT satellite. An…

Astrophysics · Physics 2009-10-31 Sergio Campana , Davide Lazzati , Maria Rosa Panzera , Gianpiero Tagliaferri

We use the INTEGRAL all-sky hard X-ray survey to perform a statistical study of a representative sample of nearby AGN. Our entire all-sky sample consists of 127 AGN, of which 91 are confidently detected (>5 sigma) on the time-averaged map…

Astrophysics · Physics 2016-08-30 S. Sazonov , M. Revnivtsev , R. Krivonos , E. Churazov , R. Sunyaev

The EXIST active shields, planned for the main detectors of the coded aperture telescope, will have approximately 15 times the area of the BATSE detectors, and they will have a good geometry on the spacecraft for viewing both the leading…

Astrophysics · Physics 2007-05-23 Colleen A. Wilson , G. J. Fishman , J. -S. Hong , J. E. Grindlay , H. Krawczynski

We introduce new methods for robust high-precision photometry from well-sampled images of a non-crowded field with a strongly varying point-spread function. For this work, we used archival imaging data of the open cluster M37 taken by MMT…

Instrumentation and Methods for Astrophysics · Physics 2015-06-24 S. -W. Chang , Y. -I. Byun , J. D. Hartman

Extensive astronomical surveys, like those conducted with the {\em Chandra} X-ray Observatory, detect hundreds of thousands of unidentified cosmic sources. Machine learning (ML) methods offer an efficient, probabilistic approach to classify…

Instrumentation and Methods for Astrophysics · Physics 2026-01-09 Shivam Kumaran , Samir Mandal , Sudip Bhattacharyya

Context. The Crab nebula has been used as a celestial calibration source of the X-ray flux and spectral shape for many years by X-ray astronomy missions. However, the object is often too bright for current and future missions equipped with…

(abridged) Hard X-ray surveys performed by the INTEGRAL satellite have discovered a conspicuous fraction (up to 30%) of unidentified objects among the detected sources. Here we continue our identification program by selecting probable…

The Burst and Transient Source Experiment (BATSE) on the Compton Gamma-Ray Observatory has been shown to be sensitive to non-transient hard X-ray sources in our galaxy, down to flux levels of 100 mCrab for daily measurements, 3 mCrab for…

Astrophysics · Physics 2007-05-23 V. Connaughton , C. R. Robinson , M. L. McCollough , S. A. Laurent-Muehleisen
‹ Prev 1 8 9 10 Next ›