The ARAE research group (ICT-189 amongst the information technology groups) was founded in 2001, although some of its members have already started their activity in 1990, and belongs to the Andalusian Research Plan (PAI) based in the Institute of Astrofísica de Andalucía (IAA) of the National Research Council (CSIC) in Granada.
The common denominator of most of the members of the research group are multi-range observations of high-energy phenomena and models of stellar population synthesis as well as the automation of small/medium size observatories and astronomical instrumentation development.
1. Areas of Research
These are: Compact objects (X-ray Binaries), cosmic gamma-ray bursts (GRBs), astrophysical transients (eg. OTs) and stellar population synthesis models.
1.1. X-ray binaries
The study of X-ray binaries (XRBs) already started in 1990, with the analysis and interpretation of data from the WATCH instrument on board the Granat satellite. Special attention has been devoted to GRO J0422 +32 (X-ray Nova Persei 1992) and GRS 1915 +105. For the first one we discover its optical counterpart, and we tested that it houses probably a black hole. Furthermore, we also observed for the first time in this type of objects, a secondary explosion in 1993. With respect to the second object, GRS 1915+105, discovered by us, it has become the first observed microquasar in the galaxy, according to radio observations. We identified the infrared counterpart, and for the first time observed emission lines in the K band IR, presumably originating in the accretion disk around the central black hole. Multi-range observations have been made in other binary systems (XTE J0929-29, XTE J1550-54, XTE J1650-500, XTE J1859+28).
1.2. Gamma-ray bursts
Gamma-ray bursts (GRBs) are one of the most important research field in high energy astrophysics. These explosions were initially studied by us using the WATCH data. In order to identify the counterparties, we extended the search to other wavelengths, in particular X bands (with Rosat, BeppoSAX), UV end (with EUVE), optical (several ground-based telescopes and HST), infrared (different telescopes ground and ISO) and submillimeter and radio (Plateau de Bure Interferometer).
Important results were achieved in 1997, in close collaboration with the BeppoSAX satellite scientific group dedicated to the study of GRBs. For the specific case of GRB 970508, the first images were obtained only 4-5-hours after the explosion-gamma, which showed the optical counterpart, being the object observed with HST and the Plateau de Bure Interferometer, and the Infrared Space Observatory.
Other important findings were the possible supernova underlying to GRB 980326, the first evidence of a collimated jet emission (GRB 990123), and the indisputable relationship between the highly energetic SN 2003 dh and GRB 030329, the finding of starburst galaxies hosting several GRBs (GRB 051022). And during the Swift satellite Era, it is worth to mention the study of the first precisely locate short-duration GRB 050509, the study of the ultra-high z GRBs (eg GRB 090423) and the afterglow spectrum study for GRB 130603B (at z = 0.35) and GRB 130606A (at z = 5.91, discovered by BOOTES-2/TELMA). We are also continuing performing multiwavelength studies with optical observatories (BOOTES network, OSN, CAHA, GTC) and satellites (XMM-Newton, Chandra and INTEGRAL).
1.3. Astrophysical Transients
It is questionable whether any of these wide category (like Optical Transients, OT) may be related to GRBs or not. In any case, we are also pursuing this research, as some of these objects seem to be related with exceptional active stars, active galactic nuclei (AGN) and quasars, amongst others.
1.4. Models of stellar population synthesis
Some team members have developed models of stellar population synthesis covering the emission due to stellar evolution from radio gamma rays. Such synthesis models were used to predict the gamma-ray galactic emission due to the decay of radioactive isotopes such as Al-26 or Fe-60, predictions to be tested with data from the INTEGRAL satellite. The models also allows to derive the X-ray emission from star-forming galaxies and theoretical correlations between different energy ranges. These models are also able to predict the rate of supernovae and, in the near future, the populations of X-ray binaries in star-forming regions.
The ARAE group at IAA-CSIC has pioneered in Spain the research in the GRB field, since the 1990’s. With over 200 per-reviewed publications in this regard, including 4 in Science and 7 in Nature, (and more than 300 GCN Circulars), the group leads opportunity programs in all national facilities and participated in space missions at co-I level (INTEGRAL, Lomonosov).
Two. Instrumental and Technological Development
BOOTES (English Burst Observer and Optical Transient Exploring System) is the first robotic observatory in Spain, with two stations. The first one is located at El Arenosillo (CEDEA-INTA) in Huelva and the second at the Experimental Station of La Mayora (EELM-CSIC) in Málaga.
The main goal is the simultaneous observation of GRBs and the study of astrophysical transients. First observations began in 1998. It is based on two observation stations, a few hundred miles apart with two robotized telescopes (30 and 60 cm), and a corresponding set of all-sky cameras. Among the most spectacular results obtained to date, highlights the discovery of the optical afterglow to GRB 130606A, at a redshift of 5.91, when the Universe was only about 1 billion years old. (more on bootes.iaa.es).
The ARAE group is also making fully robotic the T60 telescope at Observatorio de Sierra Nevada in Granada, and should become the first robotic near-IR telescope in Europe, when attaching to it the BIRCAM camera. It is not just the ability to do first-rate science which has led to the creation of the consortium, but the possibility to train technologists in the field of IR instrumentation, control of robotics and telematics (more on www.iaa.es/bootes-ir).
When no GRB alerts will be followed-up, additional near-IR in other fields (from Solar System to Extragalactic Astronomy) will be attempted.
2.3. OTHER PROJECTS
Regarding instrumentation, several of the team members have extensive
experience in the development of instrumentation both on Earth and in
space. In Earth has developed an all-sky optical camera to record the entire sky every minute (CASSANDRA) patented and licensed to a Spanish company, which installed a similar device in other parts of the country. Other initiatives being undertaken currently are: 1) a spectrograph (COLORES) for the TELMA 0.6m telescope at the BOOTES-2 station and 2) a polarimeter (EDIPO) for a 1.5m class telescope. With respect to space instrumentation, we have participated in the satellites GRANAT (international mission led by the Russian Space Agency) and INTEGRAL (led by ESA). Nowadays we participate in the instrument UBAT / UFFO-p to be launched into space aboard the Lomonosov spacecraft in 2014.