相关论文: Using collimated CZTI as all sky X-ray detector ba…

We have conducted a submillimetre mapping survey of faint, gravitationally lensed sources, where we have targeted twelve galaxy clusters and additionally the NTT Deep Field. The total area surveyed is 71.5 arcmin^2 in the image plane;…

We present new measurements of the vertical density profile of the Earth's atmosphere at altitudes between 70 and 200 km, based on Earth occultations of the Crab Nebula observed with the X-ray Imaging Spectrometer onboard Suzaku and the…

The detection of astrophysical Gamma-Ray Bursts (GRBs) has always been intertwined with the challenge of identifying the direction of the source. Accurate angular localization of better than a degree has been achieved to date only with…

Pulsars are well studied all over the electromagnetic spectrum, and the Crab pulsar may be the most studied object in the sky. Nevertheless, a high-quality optical to near-infrared spectrum of the Crab or any other pulsar has not been…

X-ray sources with very few counts can be identified with low-noise X-ray detectors such as ACIS onboard the Chandra X-ray Observatory. These sources are often too faint for parametric spectral modeling using well-established methods such…

Blazars are jetted active galactic nuclei with a jet pointing close to the line of sight, hence enhancing their intrinsic luminosity and variability. Monitoring these sources is essential in order to catch them flaring and promptly organize…

The advent of all-sky facilities, such as the Neil Gehrels Swift observatory, the All Sky Automated Search for Supernovae (ASASSN), eROSITA and Gaia has led to a new appreciation of the importance of transient sources in solving outstanding…

We present two new source extraction methods, based on Bayesian model selection and using the Bayesian Information Criterion (BIC). The first is a source detection filter, able to simultaneously detect point sources and estimate the image…

XPoSat is India's first X-ray spectro-polarimetry mission, consisting of two co-aligned instruments, a polarimeter (POLIX) and a spectrometer (XSPECT), to study the X-ray emission from celestial sources. Since polarimetry is a photon-hungry…

We present the calibration of the Insight-Hard X-ray Modulation Telescope (Insight-HXMT) X-ray satellite, which can be used to perform timing and spectral studies of bright X-ray sources. Insight-HXMT carries three main payloads onboard:…

The Galactic plane scanning survey is one of the main scientific objectives of the Hard X-ray Modulation Telescope (known as Insight-HXMT). During the two-year operation of Insight-HXMT, more than 1000 scanning observations have been…

We report results of a serendipitous hard X-ray (3--20 keV), nearly all-sky (|b|>10deg) survey based on RXTE/PCA observations performed during satellite reorientations in 1996--2002. The survey is 80% (90%) complete to a 4$\sigma$ limiting…

We present a new measurement of the cosmic X-ray background (CXRB) in the 1.5-7 keV energy band, performed by exploiting the Swift X-ray telescope (XRT) data archive. We also present a CXRB spectral model in a wider energy band (1.5-200…

The BATSE mission aboard CGRO observed the whole sky for 9 years in the 20 keV - 2 MeV energy band. Flat-fielding of the temporal variations in the background present in the data set has been accomplished through a GEANT3 Monte-Carlo…

We discuss a method for detecting the emission from high redshift galaxies by cross correlating flux fluctuations from multiple spectral lines. If one can fit and subtract away the continuum emission with a smooth function of frequency, the…

The IceCube Neutrino Observatory has discovered a diffuse all-flavor flux of high-energy astrophysical neutrinos. However, the corresponding astrophysical sources have not yet been identified. Neither significant point sources nor…

We summarize methods and plans to monitor and calibrate photometric observations with our autonomous, robotic network of 2m, 1m and 40cm telescopes. These are sited globally to optimize our ability to observe time-variable sources. Wide…

The Crab Nebula has long been the standard reference point source for very-high-energy (VHE, E $>$100 GeV) gamma-ray observatories such as VERITAS. It has enabled testing and improvement of analysis methods, validation of techniques, and…

While waiting for new gamma-ray burst detections, the Burst Alert Telescope (BAT) on board Swift covers each day ~50% of the sky in the hard X-ray band (``Survey data''). The large field of view (FOV), high sensitivity and good angular…

We present the results of our optical identifications of several hard X-ray sources from the INTEGRAL all-sky survey obtained over 14 years of observations. Having improved the positions of these objects in the sky with the X-ray telescope…