Search Publications
On the reality of broad iron L lines from the narrow line Seyfert 1 galaxies 1H 0707-495 and IRAS 13224-3809.
Misra, R.; Dewangan, G. C.; Pawar, P. K. +2 more
We performed time resolved spectroscopy of 1H0707-495 and IRAS 13224-3809 using long XMM-Newton observations. These are strongly variable narrow line Seyfert 1 galaxies and show broad features around 1 keV that has been interpreted as relativistically broad Fe L$\alpha$ lines. Such features are not clearly observed in other AGN despite sometimes h…
Performance of the mission critical Electrical Support System (ESS) which handled communications and data transfer between the Rosetta Orbiter and its Lander Philae while en route to and at comet 67P/Churyumov-Gerasimenko
McKenna-Lawlor, Susan; Schmidt, Walter; Geurts, Koen +4 more
The Electrical Support System (ESS), which was designed and built in Ireland, handled commands transmitted from the Rosetta spacecraft to the Command and Data Management System (CDMS) aboard its Lander Philae during a ten year Cruise Phase to comet 67P/Churyumov-Gerasimenko as well as at the comet itself. The busy Cruise Phase included three Earth…
Multifrequency Studies of Active Galactic Nuclei in the Planck Satellite Era
Lähteenmäki, Anne; the Planck Collaboration
The multi-epoch single-survey Planck satellite data have given a rare glimpse into how the radio spectra of active galactic nuclei (AGN) evolve in time. Using Planck and simultaneous auxiliary radio data ranging from 1 GHz to 857 GHz, spectra for 104 bright northern extragalactic radio sources (most of them AGN) have been assembled; in these, the …
Calibration of the microcalorimeter spectrometer on-board the Hitomi (Astro-H) observatory (invited)
de Vries, C. P.; Tsujimoto, M.; Ishisaki, Y. +21 more
The Hitomi Soft X-ray Spectrometer (SXS) was a pioneering non-dispersive imaging x-ray spectrometer with 5 eV FWHM energy resolution, consisting of an array of 36 silicon-thermistor microcalorimeters at the focus of a high-throughput soft x-ray telescope. The instrument enabled astrophysical plasma diagnostics in the 0.3-12 keV band. We introduce …
Reply to comment by Pätzold et al. on "Mars Express radio-occultation data: A novel analysis approach"
Witasse, O.; Blelly, P. -L.; Grandin, M. +1 more
We reply to the Comment by Pätzold et al. on our paper presenting a new analysis approach for Mars Express radio-occultation data. We address each of the main comments, showing that none of them invalidates the method itself, but rather, they underline aspects which could be considered to improve the model. One major issue raised by the Comment is…
Multiwavelength studies of X-ray selected extragalactic sample.
Mickaelian, A. M.; Abrahamyan, H. V.; Paronyan, G. M. +2 more
The joint catalogue of Active Galactic Nuclei selected from optical identifications of X-ray sources was created as a combination of two samples: Hamburg-ROSAT Catalogue (HRC) and Byurakan-Hamburg-ROSAT Catalogue (BHRC). Both are based on optical identifications of X-ray sources from ROSAT catalogues using low-dispersion spectra of Hamburg Quasar …
Characteristics of GPS sources in the Planck survey
Volvach, A. E.; Kardashev, N. S.; Larionov, M. G. +1 more
Two series of 22.2 and 36.8-GHz observations of 43 GHz-Peaked Spectrum (GPS) radio sources from the Planck survey have been carried out using the 22-m radio telescope of the Crimean Astrophysical Observatory in 2014-2015, with the aim of studying the variability of these sources. The interval between the two series of observations was about nine m…
Long-term variability of active galactic nuclei from the "Planck" catalog
Volvach, A. E.; Kardashev, N. S.; Larionov, M. G. +1 more
A complete sample of 104 bright active galactic nuclei (AGNs) from the "Planck" catalog (early results) were observed at 36.8 GHz with the 22-m radio telescope of the Crimean Astrophysical Observatory (CrAO).Variability indices of the sources at this frequency were determined based on data from theWMAP space observatory, theMetsa¨ hovi RadioObserv…
The Footprint Database and Web Services of the Herschel Space Observatory
Valtchanov, Ivan; Budavári, Tamás; Verdugo, Eva +5 more
Data from the Herschel Space Observatory is freely available to the public but no uniformly processed catalogue of the observations has been published so far. To date, the Herschel Science Archive does not contain the exact sky coverage (footprint) of individual observations and supports search for measurements based on bounding circles only. Draw…
Comment on the paper "Mars Express radio occultation data: A novel analysis approach" by Grandin et al. (2014)
Pätzold, M.; Bird, M. K.; Häusler, B. +3 more
In their recent paper, Grandin et al. (2014) claim to have developed a novel approach, principally a ray tracing method, to analyze radio sounding data from occulted spacecraft signals by planetary atmospheres without the usual assumptions of the radio occultation inversion method of a stratified, layered, symmetric atmosphere. They apply their "n…