Search Publications
Interstellar extinction in Orion: variation of the strength of the ultraviolet bump across the complex
Beitia-Antero, Leire; Gómez de Castro, Ana I.
There is growing observational evidence of dust coagulation in the dense filaments within molecular clouds. Infrared observations show that the dust grain size distribution becomes shallower and the relative fraction of small to large dust grains decreases as the local density increases. Ultraviolet (UV) observations show that the strength of the …
Cosmology with XMM galaxy clusters: the X-CLASS/GROND catalogue and photometric redshifts
Greiner, J.; Salvato, M.; Nandra, K. +11 more
The XMM Cluster Archive Super Survey (X-CLASS) is a serendipitously detected X-ray-selected sample of 845 galaxy clusters based on 2774 XMM archival observations and covering an approximately 90 deg2 spread across the high-Galactic latitude (|b| > 20°) sky. The primary goal of this survey is to produce a well-selected sample of galax…
Rapid optical variations correlated with X-rays in the 2015 second outburst of V404 Cygni (GS 2023+338)
Nogami, Daisaku; Shidatsu, Megumi; Kato, Taichi +24 more
We present optical multicolour photometry of V404 Cyg during the outburst from 2015 December to 2016 January together with the simultaneous X-ray data. This outburst occurred less than six months after the previous outburst in 2015 June-July. These two outbursts in 2015 were of a slow-rise and rapid-decay type and showed large-amplitude (∼2 mag) a…
AKARI/IRC source catalogues and source counts for the IRAC Dark Field, ELAIS North and the AKARI Deep Field South
Serjeant, S.; Pearson, C.; Matsuhara, H. +4 more
We present the first detailed analysis of three extragalactic fields (IRAC Dark Field, ELAIS-N1, ADF-S) observed by the infrared satellite, AKARI, using an optimized data analysis toolkit specifically for the processing of extragalactic point sources. The InfaRed Camera (IRC) on AKARI complements the Spitzer Space Telescope via its comprehensive c…
Exploring the multifaceted circumstellar environment of the luminous blue variable HR Carinae
Umana, G.; Agliozzo, C.; Riggi, S. +9 more
We present a multiwavelength study of the Galactic luminous blue variable HR Carinae, based on new high-resolution mid-infrared (IR) and radio images obtained with the Very Large Telescope (VLT) and the Australia Telescope Compact Array (ATCA), which have been complemented by far-infrared Herschel-Photodetector Array Camera and Spectrometer (PACS)…
Radio and infrared study of the star-forming region IRAS 20286+4105
Ojha, D. K.; Vig, S.; Ghosh, S. K. +3 more
In this paper, we present a multiwavelength investigation of the star-forming complex IRAS 20286+4105, located in the Cygnus X region. Near-infrared K-band data are used to revisit the cluster/stellar group identified in previous studies. Radio continuum observations at 610 and 1280 MHz show the presence of a H II region possibly powered by a star…
Gas kinematics in the H II regions G351.69-1.15 and G351.63-1.25
Vig, S.; Ghosh, S. K.; Veena, V. S. +2 more
We probe the structure and kinematics of two neighbouring H II regions identified as cometary and bipolar, using radio recombination lines (RRLs). The H172α RRLs from these H II regions: G351.69-1.15 and G351.63-1.25, are mapped using Giant Metrewave Radio Telescope, India. We also detect carbon RRLs C172α towards both these regions. The hydrogen …
XMM-Newton observation of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.326
Ghisellini, G.; Fan, Xiaohui; Fabian, A. C. +7 more
A brief Chandra observation of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.326 showed it to be a relatively bright, soft X-ray source with a count rate of about 1 count ks-1. In this article, we present results for the quasar from a 65-ks XMM-Newton observation, which constrains its spectral shape well. The quasar is…
Roche tomography of cataclysmic variables - VIII. The irradiated and spotted dwarf nova, SS Cygni
Szkody, P.; Hebb, L.; Hill, C. A. +1 more
We present the results of our spectroscopic study of the dwarf nova SS Cyg, using Roche tomography to map the stellar surface and derive the system parameters. Given that this technique takes into account the inhomogeneous brightness distribution on the surface of the secondary star, our derived parameters are (in principle) the most robust yet fo…
Transit-timing variations in the system Kepler-410Ab
Gajdoš, Pavol; Vaňko, Martin; Parimucha, Štefan +1 more
We present a new analysis of the transit timing variations displayed by the extrasolar planet Kepler-410Ab. We obtained and improved the orbital and physical parameters for the planet and analysed 70 transit times obtained by the Kepler satellite. In our analysis of the O-C diagram (observed minus calculated), we assumed that the observed changes …