Related papers: Variability Flagging in the WISE Preliminary Data …
Nearly one-third of the gamma-ray sources detected by Fermi are still unidentified, despite significant recent progress in this effort. On the other hand, all the gamma-ray extragalactic sources associated in the second Fermi-LAT catalog…
The most recent all-sky surveys performed with the INTEGRAL and SWIFT satellites allowed the detection of more than 1500 sources in hard X-rays above 20 keV. About one quarter of them has no obvious counterpart at other wavelengths and…
We present the results of an automated variability analysis of the Kepler public data measured in the first quarter (Q1) of the mission. In total, about 150 000 light curves have been analysed to detect stellar variability, and to identify…
Context. We use the Southern Photometric Local Universe Survey (S-PLUS) Fourth Data Release (DR4) to identify and classify H$\alpha$-excess point sources in the Southern Sky, combining photometric data from 12 S-PLUS filters with machine…
We present the result of the cross-matching between UV-excess sources selected from the UV-excess survey of the Northern Galactic Plane (UVEX) and several infrared surveys (2MASS, UKIDSS and WISE). From the position in the (J-H) vs. (H-K)…
Infrared (IR) excess observed around white dwarfs (WDs) is typically attributed to companions or debris disks. These systems are interesting because they offer a unique opportunity to study the late stages of stellar evolution and the…
This project is a massive near-infrared (NIR) search for variable stars in highly reddened and obscured open cluster (OC) fields projected on regions of the Galactic bulge and disk. The search is performed using photometric NIR data in the…
Context. The Optical Gravitational Lensing Experiment (OGLE) observed around 450,000 eclipsing binaries (EBs) towards the Galactic Bulge. Decade-long photometric observations such as these provide an exceptional opportunity to thoroughly…
We use the multi-epoch, mid-infrared Spitzer Deep, Wide-Field Survey to investigate the variability of 474,179 objects in 8.1 deg^2 of the NDWFS Bootes field. We perform a Difference Image Analysis of the four available epochs between 2004…
The Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at mid-infrared wavelengths 3.4, 4.6, 12 and 22 microns. The mission was primarily designed to extract point sources, leaving resolved and extended sources unexplored. We…
Difference imaging provides a new way to discover gravitationally lensed quasars because few non-lensed sources will show spatially extended, time variable flux. We test the method on lens candidates in the Sloan Digital Sky Survey (SDSS)…
The Wide-field Infrared Survey Explorer (WISE) has detected hundreds of millions of sources over the entire sky. However, classifying them reliably is a great challenge due to degeneracies in WISE multicolor space and low detection levels…
We present a method of reliably extracting the flux of individual sources from sky maps in the presence of noise and a source population in which number counts are a steeply falling function of flux. The method is an extension of a standard…
Here, we present the 1UVA catalog of time variable ultraviolet (UV) sources. We describe a new analysis pipeline, the VAriable Source Clustering Analysis (VASCA). We apply the pipeline to 10 years of data from the GALaxy Evolution eXplorer…
The 140 square degree Final Equatorial-Depth Survey (eFEDS) field, observed with the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) aboard the Spectrum-Roentgen-Gamma (SRG) mission, provides a first look at the variable…
We report high-resolution observations at mid-infrared wavelengths of a minor solar flare, SOL2014-09-24T17T17:50 (C7.0), using Quantum Well Infrared Photodetector (QWIP) cameras at an auxiliary of the McMath-Pierce telescope. The flare…
We present the first results of our dedicated programme of automatised classification of galaxies, stars and quasars in the mid-infrared all-sky data from the WISE survey. We employ the Support Vector Machines (SVM) algorithm, which defines…
The next generation of spectroscopic surveys is expected to provide spectra for hundreds of thousands of white dwarf (WD) candidates in the upcoming years. Currently, spectroscopic classification of white dwarfs is mostly done by visual…
We present preliminary results of a statistical analysis obtained with a sample of blazars observed at the Perugia Astronomical Observatory since 1992. We briefly show how these statistical results can be useful to discriminate faint…
Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limited sample of 140 blazars of the WMAP catalog (first year)…