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Scientific Report 2007-2009
Astronomy & Astrophysics
A11. Astronomical Databases: the Digitized First Byurakan Survey
(DFBS) and the Roma Blazar Catalogue (BZCat)
Keeping the astronomical observations for the next
generations of scientists is an important issue of science.
The time scales of phenomena in astrophysical objects
can indeed be very long and several decades or centuries
of observations are sometimes required to discover them.
Catalogues of astrophysical sources, including their position
in the sky and their luminosity at several frequencies
are therefore a key topic for research.
Our group is involved in two international projects of
this kind:
1) the digitization of the First Byurakan Survey (DFBS);
2) the realization a Blazar catalogue (Rome BZCat).
The DFBS
The First Byurakan Survey is the largest (17000
square degrees) photographic spectroscopic survey of the
northern sky made with the Schmidt telescope of the
Byurakan Observatory, with a spectral coverage from
3400 to 7000 A. Originally the survey was designed
by Markarian to discover Galaxies with Active Nuclei
(AGN) or strong star formation; more than 1500 such
galaxies were discovered by this survey.
The digitization of the plates and the automatic extraction
of the spectra of the sources has been realized
by our Group in collaboration with the Byurakan
Observatory and the Cornell University. The
database is hosted by the web server of our Group
(http://byurakan.phys.uniroma1.it/), freely accessible
by internet, containing the digitized plates of the FBS,
the individual spectra of the sources and their B and
R magnitudes. The technical details of the DFBS have
been published in 2007 [1].
The web page allows to share the database informations
with the astronomical community and to stimulate
new ideas, extending the use of the database itself to
study objects completely different from the targets of
the original survey:
- after the realization of the DFBS a research project on
asteroids has started, to improve their orbital parameters
and to have a first estimate of their surface characteristics
from their optical spectra;
- a new program has begun to search and study extremely
red objects at high galactic latitudes. Nearly
1000 late M-type and carbon stars have been selected.
Discovery of such objects is necessary for the study of
the kinematics and chemical composition of the galactic
Halo[2].
A general description of the FBS and the possibilities
of its scientific applications can be found in a dedicated
book where the future developments are also
described[3]. We have started the integration of the
DFBS database in the Astrophysical Virtual Observatories
(AVOs) project, an International enterprise aiming
to share observing materials and software tools to
form a common research environment in which complex
research programs can be conducted.
Figure 1: The spectrum of the asteroid 104 Klymene in the
plate N. 126 taken on Nov 14, 1969, widened by the asteroid
motion during the exposure.
The Roma BZCat
Our group also compiled a catalogue of blazars which
is accessible at the web site of ASDC. This catalogue and
its use is described in the section on X and gamma-ray
sources.
Figure 2: A pre-discovery (1971) spectrum of the Nova KT
Eri (2009) in the DFBS, showing strong emission lines.
References
1. A.M. Mickaelian et al., A&A 464, 1177, (2007)
2. C. Rossi et al Ap 52, 523, (2009)
3. E. Massaro et al. (editors), The Digitized First Byurakan
Survey, (2008) Aracne Editrice, Roma.
Authors
Gaudenzi S., Massaro E., Nesci R., Rossi C., Sclavi S.
http://byurakan.phys.uniroma1.it/
Sapienza Università di Roma 158 Dipartimento di Fisica