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PECS Project 98023 Report for Year 2005
ESA PECS Project Czech Participation on INTEGRAL
1. Objectives planned for the reporting period
The Czech participation includes the project co-ordination and local management
(including the Czech INTEGRAL science team and Ondrejov Integral Data Center)
within the Czech Republic, international collaboration and links, and focuses on
direct participation on ISDC and OMC activities as follows.
Direct participation in the Integral Science and Data Center (ISDC) operation
and activities by providing one person continuously working directly within the
ISDC team (as well as other persons occasionally visiting ISDC). The person at
the ISDC participated both in the service work of the ISDC (especially contribution
to the software engineering and active participation in the ISDC operations),
as well as in scientific analyses. The person is expected to work on the ISDC
software improvements, modifications and maintenance, and on scientific operations
and data analyses. Participation on scientific program will cover observations,
data analyses, data archiving, data interpretations and scientific evaluations.
Further development and updates of software, in close collaboration with ISDC
in Versoix, and transfer of ISDC s/w packages, further development of tools for
effective and inter-active scientific analyses and use of the INTEGRAL data,
further improving the quality of both astrometry and photometry, and the operation
of the second (local) ISDC center/office (Ondrejov Integral Data Center, OIDC)
at the Astronomical Institute Ondrejov enabling the astronomical community from
the Czech Republic and Central and East Europe to attend the INTEGRAL related
scientific activities, data evaluation, data archiving, and interpretation.
The scientific activities will focus on allocated scientific tasks, especially
Cataclysmic Variables and white dwarfs, Gamma ray Bursts, and Blazars-AGNs
(for more details see the WP 4).
Participation in the Optical Monitoring Camera (OMC) INTEGRAL onboard experiment
operation and science, with focus on: (1) OMC onboard s/w operation and maintenance:
collaboration with INTA Madrid in the maintenance of this package, mainly on centering
algorithm and data compression. (2) OMC ISOC s/w with focus on OMC pointing software
(Ref. OMC/INT/90000/SRD/001) (3) maintenance and operation of the OMC test device
(4) maintenance and operation of the OMC simulator which allows to predict the flight
camera images for any given sky position (4) OMC interactive analysis package
development and operation in collaboration with LAEFF/INTA Madrid (5) ground/based
segment operation, further development, and maintenance with focus on ground/based
telescopes (especially the sub-experiment BOOTES developed and operated in
collaboration between the Astronomical Institute and LAEFF Madrid, Spain) and
cameras to provide supporting observations to INTEGRAL activities, simultaneous
and follow-up observations etc., and (6) OMC science with participation on scientific
program, observations, data interpretations and scientific evaluations.
Allocated scientific tasks will include the management of the INTEGRAL Core
Program Working Group "White Dwarfs including Cataclysmic Variables", ID number
5.5, R. Hudec R_Sci (responsible scientist R. Hudec nominated by the INTEGRAL ISWT)
as well as the participation in the operation of the Core Program ID 4.3 (Active
Galactic Nuclei and Blazars), 4.3.1. (Time variability study), 4.3.2. (Active
galactic nuclei observable above 20 keV), 4.3.4. (Object Mrk 501 including TOO
follow-up observations) 4.4.1. (Global properties of gamma ray bursts and individual
sources), 5.3.5.1 (Accreting pulsars including cyclotron lines, known persistent sources),
5.3.5.2. (Accreting pulsars incl. Cyclotron lines, known transient sources), 5.3.6.
(Bright low mass X-ray binaries) (in these categories/topics is the applicant
included in the collaboration teams according to the INTEGRAL Core Program Document
INT-TN-26770). Within the ID 4.3., a small dedicated working group focusing on
blazars will be established and operated in collaboration with the corresponding
R_Sci and Finnish collaborators from the Tuorla Observatory.
2. Results achieved
2.1. Data analyses and science
We presented selected results of observations of cataclysmic variables (CVs)
and related objects by the instruments IBIS and OMC onboard INTEGRAL.
We concentrated mainly on the analysis of the time behaviour of the intermediate
polar (IP) V1223 Sgr, seen simultaneously by IBIS and OMC in a state of brightness
which we call a shallow low state. We had a unique opportunity to investigate the
relation between the activity in the optical and far X-ray region on long time scales;
we presented far X-ray spectra (E up to 60 keV) and the relation between far X-ray and
optical flux. We demonstrated their stability during this state over an interval
of 400 days. Even in this state, both the profile of the optical modulation with
the orbital period and the phase of the minimum light in the OMC data are in good
agreement with those determined by Jablonski and Steiner (1987) for the high state.
The beat period is still dominant, which suggests that the stream-disk overflow
still operates in this state of activity.
We also presented far X-ray observations of some other magnetic CVs (V1432 Aql,
V2400 Oph, GK Per) and showed that the systems with magnetized white dwarf (like
polars and IPs) appear to be the most promising CVs for INTEGRAL.
We showed that IBIS observations caught the intermediate polar/dwarf nova GK
Per almost between the consecutive outbursts. The flux in the 25 - 40 keV passband
of IBIS was found to be consistent with an extrapolation of the X-ray spectrum
obtained by Ishida et al. (1992) in a similar state. We therefore argue that the
amount of matter arriving to the WD and the parameters of the X-ray emitting region
on the white dwarf remained almost the same during these phases of the quiescent
intervals.
We also presented the examples of the OMC light curves and showed that the outburst
and a shallow low state of IX Vel are caused by the mass transfer variations,
and not by the thermal instability of the disk, and that the amplitude of the
flickering decreases with the decreasing intensity of the "stable" component.
Analogous analyses were performed also for blazars and other targets.
We have also participated in INTEGRAL GRB data analyses (e.g. GRB 040403 -
a faint X-ray rich gamma-ray burst discovered by INTEGRAL) and in INTEGRAL ToO
observations (within of accepted AO2 and AO3 observing proposals) of two flaring
blazars (S5 0716+714 and 3C345) as members of collaboration lead by Elena Pian.
The results have been in collaboration presented on international scientific
conferences and in scientific papers.
2.2. ISDC participation
The participation in ISDC (INTEGRAL Science and Data Centre) in Versoix continued
according to the plan with a full involvement of Petr Kubanek.
idx_merge tool. Idx_merge is tool program developed at ISDC, which is
used in archive processing for merging two FITS indices together. Petr Kubanek
carried benchmark tests for providing information about possible speed-up in this
program. Tests identified fast-merge patch as best possible solution. Fast-merge
patch was developed by Petr, tests for that patch were made, and patch was delivered
to ISDC. That patch significantly speed-up archive processing.
ISR - Integral Source Results web pages. Based on discussion with Mathias Beck,
Mohamed Meherga and Roland Walter, Petr Kubanek created web pages "Integral Source Results",
which allows users not familiar with the OSA (Offline Scientific Analysis,
software package used to analyse INTEGRAL data) access data products from standard
OSA runs, which are executed at ISDC.
The web pages enables access to objects light-curves, spectra and IBIS and
JEMX processed images. They currently contains processed data for all public
observations of sources, which were flagged as detected in INTEGRAL Source Results
catalogue, version 15. ISDC is expected to reprocess those data with new OSA
release 5.0/5.1 later this year, which will provide even better results at this
quick-look page.
ISR web-pages can be accessed on http://isdc.unige.ch/Data/ISR/isr.cgi. User
guide for ISR was written, as well as ISR description to ISDC Newsletter. ISR Perl
source code was fully documented, and delivered as ISDC SW package.
lc_extract tools. Based on discussion with Filip Munz, Petr Kubanek
developed lc_extract tools, which were tried for extraction of weak sources countrates
from the INTEGRAL IBIS detector. We expect, that they will continue developing
and further process INTEGRAL data next year, after Petr finish ISDC VO project.
Lc_extract use variation of pure open/close mask element method to detect weak
sources inside IBIS field of view.
2.3. VO - Virtual Observatory at ISDC
Almost all facilities, which deals with astronomical data archiving, contribute
to the development of Virtual Observatory. Virtual Observatory can be used for
quick multispectral analysis of various sources and computer-driven data mining
and processing. It can help researchers to guickly gain access to information
they needed in format they can use, so they can focus on validation of their
theories instead of learning various methods for processing data from various
Earth and space based observatories.
We significantly contributed to development of Virtual Observatory conforming
access to INTEGRAL data. Petr Kubanek prepared environment for enabling Virtual
Observatory enabled access to INTEGRAL data. That included instalation and
configuration of Apache Tomcat server on ISDC Solaris computers. He decided to
implement VO services at ISDC as set of Java Servlets - main reasons for that was
his experience with Java Servlets, which he found superiors to Perl::CGI approach.
Object oriented programming (OOP), which is base of Java language, allows better
design of complex programs. At costs of longer design phase, it enables better
grow of initial small code subsets to full feature services then procedural
programming. It also promotes separation of code to small subsets with clearly
defined interfaces. Thanks to that aproach code can be reused.
It should be noted, that OOP was also introduced to Perl, but as Perl wasn't
invented for OOP, OOP implementation in it is introduced at costs of various design
requirements, which layer OOP over original Perl procedural language.
Java also introduced JavaDoc for writing documentation directly in code, which
enables better and more up-to date documentation then writing separate programming
documentation.
After taking decision about target enviroment (Java Servlet Container - Tomcat
from Apache foundation), he implement VO access to INTEGRAL catalogue. That first
servlet was used as prototype for developing of another servlet, which handles
FITS images search and extraction.
Currently we have finished prototype for VO access to INTEGRAL IBIS mosaics.
We expect to offer VO access to world astronomical community later this year,
after we further develop VO access, bringing it from prototype to production
status and put other high-level products to VO database for all INTEGRAL
instruments.
As was already noted by various VO developers, the only currently avaiable pure
Java library to access FITS files, nom.tam.fits library, have significant drawbacks.
Those included bugs in reading big gzipped files, which results in inability to read
most of the INTEGRAL data and lack of WCS (World Coordinate Systems) extensions
(which are used to store information about which part of the sky image contains)
support Petr Kubanek patched nom.tam.fits library, so he can use it in his VO
servlets. But based on discussions with other VO developers, he decided to recode
Java FITS access library, so it will not suffer from drawbacks noted during its use.
He also make changes to UK Starlink "Starjava" package, so he can use it to
quickly generate pages used for VO access.
2.5. Other works and activities
The secondary science centre in Ondrejov was operated smoothly. New
versions of OSA data analysis software were transferred and successfully installed.
Data for most promissing sources are being reprocessed with this newest OSA software
and organized in local archive in a way that allows a construction of any combination
of SCWs on demand.
Source database. An imp ortant amount of time was devoted to the development
of the web interface for INTEGRAL working groups, devoted for studies of blazars
(http://altamira.asu.cas.cz/iblwg) and cataclysmic variable (CV) stars
(http://altamira.asu.cas.cz/icvwg). Most of features of these pages are supplied
by a common code written in PHP with underlying MySQL database. On one hand this
database is filled with information from ISDC archive (position and quality
of individual pointings), on the other hand with available HE data on the sources
to predict their possible detection with INTEGRAL instruments. We still lack more
information on X-ray spectra of CVs (only a small collection of about 20 spectra from
ASCA observations is available above 1 keV). For blazar database based on the article
by Donato et al the most promising sources can be obtained from
this script.
Recently a new large set of possible blazar positions (about 700, half of them
corresponding to Veron-Cetty AGN locations) from astro-ph/0506720 was included.
I am currently checking the candidates with highest exposures.
A new feature of these web pages is
a scheduler, that uses data from ISOC pages
(a complex script for retrieval of scheduled pointings and their import in the
database was written by Jiri Polcar). This allows to plan simultaneous observations
with optical telescopes in advance, not just react to GCN alerts about new
INTEGRAL pointings (more suitable for robotic telescopes). In some cases a given
source is under horizon at the time of INTEGRAL observation so the optical
monitoring should be performed before the alert is issued.
Weak source analysis. Our basic tool for extraction of physical data
from reconstructed images is mosaic_spec, a small program in C intended originally
as an alternative to standard spectral analysis (started at ISDC with Roland
Walter in the end of 2004). While the old version is currently employed by INTEGRAL
Source Result web interface to ISDC archive (described elsewhere in this document),
I added some new features that allow to obtain more information about the shape of
the analysed peak in IBIS image, the properties of the background (to sort out
most of false detections) and finally retrieve a cutout from a large mosaic.
The latter feature allows to reduce significantly (by several ordres of magnitude)
the amount of data needed to transfer from ISDC when analyzing large mosaics
(either available directly for pre-defined observation groups - OGs - or constructed
from selected SCWs using ii_skyimage mosaicing capability). Since the energy binning
of reconstructed IBIS images in ISDC archive (revision 2) is too fine for the search
of weak sources, mosaic_spec can also sum-up several energy bins together to improve
the statistics. The cut-outs should be available soon (once the bitmap conversion
is mastered) through the web pages mentioned above.
The analysis of short-time pre-defined OGs (of length up to 3 days) is well suited
for blazar studies (whose flares can appear at these time scales) but not so much
for search of cataclysmic variables (whose variability has more periodic nature).
In the cases their basic periods (orbital, rotation or beat of these two) are known
we could employ phase resolved analysis. For this purpose a new tool called lc_extract
was developped by Petr Kubanek, that uses pixel illumination factor (PIF) method
similar to standard IBIS light curve extraction process, but should be less
sensitive to variations of fluxes of strong sources in the field of view (which
is the case for CVs close to the Galactic bulge). The production version of this
tool script should include also GTI and noisy pixel treatment.
For our most prominent source of CV category, V1223 Sgr, we have tried a different
method for phasogram construction suitable for periods of the order of hours.
The set of about 250 SCWs was divided into 10 time bins according to the phase
of the middle of their exposures and a mosaic was constructed for each of these bins.
The phasogram obtained was statistically flat, but greatest obstacle for this
method arises from the fact that the absolute flux calibration for IBIS is far
from perfect for individual SCWs: even for sources as strong and stable as Crab
the fluxes extracted with latest OSA package show variations up to 10%.
We also searched for possible spectral variations of V1223 Sgr through different
observation seasons (the exposures of this source - counting only those within
10 degrees off axis - are divided in groups separated by roughly 6 months).
No significant change in spectral slope (or rather hardness ratio) was observed.
Participation in OMC INTEGRAL data analyses have continued. A dedicated meeting
of Czech and Spanish specialists was held at LAEFF, Madrid, in September 2005,
with focus on improvements of experiment calibration and data analyses.
An Czech INTEGRAL Project Progress Meeting was held in Jindrichuv Hradec,
Czech Republic, November 13 - 16, 2005, with numerous presentations and discussions.
7. Publications/papers presented based on the project
Presentations
V.Simon, R. Hudec, F. Munz, J. Strobl: INTEGRAL and cataclysmic variables,
Frascati Workshop, 23rd - 28th May 2005, Vulcano, Italy
V. Simon, R. Hudec, F. Munz, J. Strobl: Cataclysmic variables and related objects
with INTEGRAL, IAU Symposium 230: Populations of High Energy Sources in Galaxies,
15th - 19th August 2005, Dublin, Ireland
V. Simon, R. Hudec, F. Munz, J. Strobl: Activity of V1223 Sgr observed with INTEGRAL,
The X-ray Universe 2005, 25th - 30th September 2005, San Lorenzo de El Escorial, Spain
Hudec R. et al. Observations of blazars by INTEGRAL, INTEGRAL Internal Science
Workshop, Noordwijk, Jan 2005
Simon V. et al. Observations of cataclysmic variables and related objects by
INTEGRAL, INTEGRAL Internal Science Workshop, Noordwijk, Jan 2005
Hudec R. et al. Cataclysmic Variables by Integral. ISDC Consortium Meeting,
Versoix, Switzerland, Oct 11, 2005
Hudec R. et al. INTEGRAL Data Analyses ISGRI and OMC / cataclysmic variables.
2nd INTEGRAL Data Analysis Workshop, Versoix, Switzerland, Oct 13, 2005
Kubanek P., Virtual Observatory and INTEGRAL Data. 2nd INTEGRAL Data Analysis
Workshop, Versoix, Switzerland, Oct. 13 2005
X-ray Astronomy 2005, El Escorial, Oct 2005: Hudec R. et al. INTEGRAL and Blazars.
Moriond Conference Very High Energy Phenomena in the Universe 2005 Hudec R. Blazars:
INTEGRAL and Supermassive Black Hole Binaries.
Moriond Conference Very High Energy Phenomena in the Universe 2005.
Munz F. Searches for Weak and Variable sources by INTEGRAL.
International workshop Multivawelength behaviour of high energy cosmic sources,
Vulcano 2005, May 2005 Hudec R. et al. INTEGRAL and Blazars. Simon V., Hudec R. et al.
Observations of cataclysmic Variables by the INTEGRAL satellite.
IAU 230 High Energy Sources in Galaxies, IAU Symposium 230, Dublin, August 2005
Simon V. et al. Observations of cataclysmic Variables by the INTEGRAL satellite.
Hudec R. Blazars and INTEGRAL
Publications
V. Simon, R. Hudec, F. Munz, J. Strobl: Cataclysmic variables observed with INTEGRAL,
Chinese Journal of Astronomy and Astrophysics, in press
V. Simon, R. Hudec, F. Munz, J. Strobl: Cataclysmic variables and related objects
with INTEGRAL, Proceedings of the IAU Symposium 230: Populations of High Energy
Sources in Galaxies, in press
V. Simon, R. Hudec, F. Munz, J. Strobl: Activity of V1223 Sgr observed with
INTEGRAL, Proceedings of The X-ray Universe 2005, ESA publications division,
in press
Hudec, R.; Šimon, V.; Štrobl, J.; Munz, F.: INTEGRAL Core Programme and Cataclysmic Variables,
The Astrophysics of Cataclysmic Variables and Related Objects, Proceedings of ASP
Conference Vol. 330. Edited by J.-M. Hameury and J.-P. Lasota. San Francisco:
Astronomical Society of the Pacific, 2005., p.479
Šimon, V.; Hudec, R.; Štrobl, J.; Hroch, F.; Munz, F.: Observations of Cataclysmic
Variables with INTEGRAL; Journal: The Astrophysics of Cataclysmic Variables and
Related Objects, Proceedings of ASP Conference Vol. 330. Edited by J.-M. Hameury
and J.-P. Lasota. San Francisco: Astronomical Society of the Pacific, 2005., p.477
Hudcová, V.; Hudec, R.; Polcar, J.; Hroch, F.: Observing with OMC/INTEGRAL;
The Astrophysics of Cataclysmic Variables and Related Objects, Proceedings of ASP
Conference Vol. 330. Edited by J.-M. Hameury and J.-P. Lasota. San Francisco:
Astronomical Society of the Pacific, 2005., p.475
Mereghetti, S.; Götz, D.; Andersen, M. I.; Castro-Tirado, A.; Frontera, F.; Gorosabel,
J.; Hartmann, D. H.; Hjorth, J.; Hudec, R.; Hurley, K.; Pizzichini, G.; Produit,
N.; Tarana, A.; Topinka, M.; Ubertini, P.; de Ugarte, A.: GRB 040403:
A faint X-ray rich gamma-ray burst discovered by INTEGRAL; Astronomy and Astrophysics,
Volume 433, Issue 1, April I 2005, pp.113-116 (A&A Homepage)
Authors: Pian, E.; Foschini, L.; Beckmann, V.; Sillanpää, A.; Soldi, S.;
Tagliaferri, G.; Takalo, L.; Barr, P.; Ghisellini, G.; Malaguti, G.; Maraschi,
L.; Palumbo, G. G. C.; Treves, A.; Courvoisier, T. J.-L.; Di Cocco, G.; Gehrels,
N.; Giommi, P.; Hudec, R.; Lindfors, E.; Marcowith, A.; Nilsson, K.; Pasanen, M.;
Pursimo, T.; Raiteri, C. M.; Savolainen, T.; Sikora, M.; Tornikoski, M.; Tosti,
G.; Türler, M.; Valtaoja, E.; Villata, M.; Walter, R.: INTEGRAL observations of
the field of the BL Lacertae object S5 0716+714; Astronomy and Astrophysics,
v.429, p.427-431 (2005) (A&A Homepage)
Hudec, R.: Astronomical Plate Archives as Supplementary Data for INTEGRAL Science;
Proceedings of the 5th INTEGRAL Workshop on the INTEGRAL Universe (ESA SP-552).
16-20 February 2004, Munich, Germany. Scientific Editors: V. Schönfelder,
G. Lichti & C. Winkler, p.851
Simon, V.; Hudec, R.; Hroch, F.: Rapid Variations in RS Oph Observed by OMC/INTEGRAL;
Information Bulletin on Variable Stars, 5562, 1. (IBVS Homepage)
Papers and talks presented at the Czech INTEGRAL project Progress Meetings,
Jindrichuv Hradec, November 13-16, 2006
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