Annual report - 2007

Results achieved 

INTEGRAL satellite data analyses and science 
Scientific Highlights

We presented selected results of observations of cataclysmic variables (CVs) and related objects by the instruments IBIS, JEM.X, and OMC onboard INTEGRAL. 

Eight contributions (two oral talks and 6 posters) were presented at the INTEGRAL international science workshop held in Chiu, Italy, in October 2007. See end of this paper for the titles of the presentations. Two contributions on INTEGRAL results were presented on the international Frascati Workshop The multispectral behaviour of cosmic high-energy sources held in Vulcano, Italy, in May 2007. 

Several INTEGRAL-related contributions were presented at the 39. Variable Star Conference held in Valasske Mezirici in November 2007, for more details and program see http://var.astro.cz/akce/konf2007/program.pdf., and International workshop KOLOS2007 held in Snina, Slovakia, in November 2007. For titles of the talks see the end of this report. 

For more project-related presentations on international conferences and consortia meetings see the list at the end of this report. 

We have presented further selected results of observations and monitoring of cataclysmic variables (CVs) and related objects by the instruments IBIS, JEM X, and OMC onboard INTEGRAL. For the first time, the JEM-X data were added to the analyse. We presented hard X-ray observations of eight CVs (or at least upper limits of their far X-ray fluxes) and show that the systems with magnetized white dwarf (like polars and IPs) are observable with INTEGRAL. The OMC light curves habe been also used for the komplex view on the objects. For more details see e.g. New results on cataclysmic variables observed by INTEGRAL., Authors: Hudec R., Simon V., Munz F., Galis R., Journal: Chinese Journal of Astronomy and Astrophysics, 2007, accepted.. 

 These promising results have resulted in invitation of R. Hudec to give an invited talk in the highly recognized internation workshop with participation only by invitation‚ Multi-frequency behaviour of cosmic high-energy sources in Vulcano, Italy, in May 2007. Another two talks on INTEGRAL results by our group were given at the INTEGRAL Science Workshop in Italy, October 2007. Both talks can be downloaded from http://www.sciops.esa.int/index.php?project=INTEGRAL&page=5th_anniversary_programme  

The observations and detections of CVs and related objects have been reviewed and presented at ISDC Consortium Meeting. There are recently 21 We have performed GRB studies with JEM-X, for more details see Hudec R. Recent results on INTEGRAL Observations of cataclysmic variables and symbiotic stars, oral talk 30 min. ISDC Consortium Meeting, ISDC, Apríl 16-17, 2007 http://isdc.unige.ch/index.cgi?Meetings+meet_cons+bin/ascii.cgi?../rep/meet/cons/cons-36_vg_links.html  

In international collaboration, an analogous study was performed also for a specific class of active galactic nuclei, blazars, where data both within the INTEGRAL Core Programme as well as in pointed AO observations have been analysed, evaluated, interpreted and discussed (in total 20 blazars and related objects). It has been demonstrated that the pointed observations with times exceeding 200 ksec may provide valuable scientific results for this class of extragalactic objectsFor more details see e.g Investigation of blazars with the INTEGRAL satelite, Authors: Hudec R., Munz F., Kubanek P., Pian E., Journal: Nuclear Physics B, Volume 166, April 2007, Pages 229-233 

We have continued extended studies and works on identification and optical long-term anylyses of INTEGRAL gamma-ray sources with use of astronomical archival plates. This is a novel promising and cost-effective approach. Two extended suitable databases have been used for this study, at Leiden and Sonneberg Observatories, covering positions of many INTEGRAL sources with hundreds of deep archival astronomical plates. In some cases, the evolution of the sources could be studied for time intervals as long as of 80 years with some sources found to show violent light changes with almost 3 magnitudes amplitudes. For more details we refer to e.g.. Hudec R Investigation of Integral sources on astronomical archival plates. Poster presented at Integral Science Workshop, Sardinia, Italy, October 17-19, 2007. 

An effort continued to be devoted to the analysis of INTEGRAL OMC data. The reliability of the OMC optical data has been further analysed and the data proved to be sufficient for some individual optically variable objects and the analysis can hence leads to publishable results. The eclipsing binaries may serve as an example. This is considered as an important contribution by the Czech INTEGRAL team as the OMC data are not widely used by others. For more details see e.g. Hudec R. and Sobotka P. Integral OMC and Variable Stars. Poster. Integral Science Workshop, Sardinia, Italy, October 17-19, 2007 

We have continued the efforts in INTEGRAL data mining for faint and variable objects. The quest of data mining from INTEGRAL archive maintained at ISDC (now in revision 3) had moved from extracting and analyzing regions of mosaics already existing in the archive (constructed on per-revolution basis) to constructing new mosaics from images of individual science windows, containing sources of interest. Intelligent algorithm selects SCWs to cover all spurious sources nearby from given catalogue (Donato et al for blazars, Downes for CVs) in order to cover maximal number of targets in the least number of mosaics. These methods were applied e.g. to searches for counterparts of TeV sources, see eg. Munz F. and Hudec R., presentation at JENAM 2007, Jerevan, Armenia. 

As R. Hudec is the R_Sci for topic of cataclysmic variables, on several occasions during 2007 we presented selected results of observations of cataclysmic variables (CVs) and related objects by the instruments IBIS, JEM-X and OMC onboard INTEGRAL. In the most extensive search for CVs in the archive, the average exposure of 176 mosaics was almost 1000 ksec, containing positions of hundreds of CVs. The extracted regions should soon become available through INTEGRAL CV working group pages. The dataset is now extended in a view of 4rd IBIS survey, containing important detections of 21 CVs. We hope to get improved sensitivity with OSA7 software recently issued and that significant fraction of INTEGRAL archive is processed with it.