Ronan Cunniffe

PANCHROMATIC OBSERVATIONS OF THE TEXTBOOK GRB 110205A: CONSTRAINING PHYSICAL MECHANISMS OF PROMPT EMISSION AND AFTERGLOW

We present a comprehensive analysis of a bright, long-duration (T-90 similar to 257 s) GRB 110205A at redshift z = 2.22. The optical prompt emission was detected by Swift/UVOT, ROTSE-IIIb, and BOOTES telescopes when the gamma-ray burst (GRB) was still radiating in the gamma-ray band, with optical light curve showing correlation with gamma-ray data. Nearly 200 s of observations were obtained simultaneously from optical, X-ray, to gamma-ray (1 eV to 5 MeV), which makes it one of the exceptional cases to study the broadband spectral energy distribution during the prompt emission phase. In particular, we clearly identify, for the first time, an interesting two-break energy spectrum, roughly consistent with the standard synchrotron emission model in the fast cooling regime. Shortly after prompt emission (similar to 1100 s), a bright (R = 14.0) optical emission hump with very steep rise (alpha similar to 5.5) was observed, which we interpret as the reverse shock (RS) emission. It is the first time that the rising phase of an RS component has been closely observed. The full optical and X-ray afterglow light curves can be interpreted within the standard reverse shock (RS) + forward shock (FS) model. In general, the high-quality prompt and afterglow data allow us to apply the standard fireball model to extract valuable information, including the radiation mechanism (synchrotron), radius of prompt emission (R-GRB similar to 3 x 10(13) cm), initial Lorentz factor of the outflow (Gamma(0) similar to 250), the composition of the ejecta (mildly magnetized), the collimation angle, and the total energy budget.

Flares from a candidate Galactic magnetar suggest a missing link to dim isolated neutron stars

Magnetars are young neutron stars with very strong magnetic fields of the order of 1014–1015 G. They are detected in our Galaxy either as soft γ-ray repeaters or anomalous X-ray pulsars. Soft γ-ray repeaters are a rare type of γ-ray transient sources that are occasionally detected as bursters in the high-energy sky. No optical counterpart to the γ-ray flares or the quiescent source has yet been identified. Here we report multi-wavelength observations of a puzzling source, SWIFT J195509+261406. We detected more than 40 flaring episodes in the optical band over a time span of three days, and a faint infrared flare 11 days later, after which the source returned to quiescence. Our radio observations confirm a Galactic nature and establish a lower distance limit of ∼3.7 kpc. We suggest that SWIFT J195509+261406 could be an isolated magnetar whose bursting activity has been detected at optical wavelengths, and for which the long-term X-ray emission is short-lived. In this case, a new manifestation of magnetar activity has been recorded and we can consider SWIFT J195509+261406 to be a link between the ‘persistent’ soft γ-ray repeaters/anomalous X-ray pulsars and dim isolated neutron stars.A. J. Castro-Tirado, A. de Ugarte Postigo, J. Gorosabel, M. Jeĺınek, T. A. Fatkhullin, V. V. Sokolov, P. Ferrero, D. A. Kann, S. Klose, D. Sluse, M. Bremer, J. M. Winters, D. Nuernberger, D. Pérez-Ramı́rez, M. A. Guerrero, J. French, G. Melady, L. Hanlon, B. McBreen, F. J. Aceituno, R. Cunniffe, P. Kubánek, S. Vitek, S. Schulze, A. C. Wilson, R. Hudec, J. M. González-Pérez, T. Shahbaz, S. Guziy, S. B. Pandey L. Pavlenko, E. Sonbas, S. A. Trushkin, N. N. Bursov, N. A. Nizhelskij and L. Sabau-Graziati

Early optical follow-up of the nearby active star DG CVn during its 2014 superflare

DG CVn is a binary system in which one of the components is an M type dwarf ultra fast rotator, only three of which are known in the solar neighborhood. Observations of DG CVn by the Swift satellite and several ground-based observatories during its super-flare event on 2014 allowed us to perform a complete hard X-ray - optical follow-up of a super-flare from the red-dwarf star. The observations support the fact that the super-flare can be explained by the presence of (a) large active region(s) on the surface of the star. Such activity is similar to the most extreme solar flaring events. This points towards a plausible extrapolation between the behaviour from the most active red-dwarf stars and the processes occurring in the Sun.

The dark nature of GRB 130528A and its host galaxy

Aims. We study the dark nature of GRB 130528A through multi-wavelength observations and conclude that the main reason for the optical darkness is local extinction inside of the host galaxy. Methods. Automatic observations were performed at the Burst Optical Observer and Transient Exploring System (BOOTES)-4 /MET robotic telescope. We also triggered target of opportunity (ToO) observations at Observatorio de Sierra Nevada (OSN), IRAM Plateau de Bure Interferometer (PdBI) and Gran Telescopio Canarias (GTC + OSIRIS). The host galaxy photometric observations in optical to near-infrared (nIR) wavelengths were achieved through large ground-based aperture telescopes, such as 10.4 m Gran Telescopio Canarias (GTC), 4.2 m William Herschel Telescope (WHT), 6 m Bolshoi Teleskop Alt-azimutalnyi (BTA) telescope, and 2 m Liverpool Telescope (LT). Based on these observations, spectral energy distributions (SED) for the host galaxy and afterglow were constructed. Results. Thanks to millimetre (mm) observations at PdBI, we confirm the presence of a mm source within the XRT error circle that faded over the course of our observations and identify the host galaxy. However, we do not find any credible optical source within early observations with BOOTES-4 /MET and 1.5 m OSN telescopes. Spectroscopic observation of this galaxy by GTC showed a single faint emission line that likely corresponds to [OII] 3727 angstrom at a redshift 1.250 +/- 0.001, implying a star formation rate (M-circle dot/yr) > 6.18 M-circle dot/yr without correcting for dust extinction. The probable line-of-sight extinction towards GRB130528A is revealed through analysis of the afterglow SED, resulting in a value of A(V)(GRB) >= 0.9 at the rest frame; this is comparable to extinction levels found among other dark GRBs. The SED of the host galaxy is explained well (chi(2)/d.o.f. = 0.564) by a luminous (M-B = -21.16), low-extinction (A(V) = 0, rest frame), and aged (2.6 Gyr) stellar population. We can explain this apparent contradiction in global and line-of-sight extinction if the GRB birth place happened to lie in a local dense environment. In light of having relatively small specific star formation rate similar to 5.3 M circle dot/yr (L/L*)(-1), this also could explain the age of the old stellar population of host galaxy.

GLORIA: The First Free Access e-Infrastructure of Robotic Telescopes for Citizen Science

This paper describes the GLORIA system (GLObal Robotic telescope Intelligent Array), the first worldwide network of robotic telescopes, which covers four continents with seventeen telescopes, and can be extended. The network architecture has been designed taking into account the functionalities offered to the community, the number of telescopes, users that will be managed and network compatibility with all kinds of robotic telescopes. Different kinds of experiments have been designed to support the various requirements of astronomers. In order to manage the user access to the network resources, an evaluation system, called karma, has been defined which will operate according to some established policy.

Compact low resolution spectrograph, an imaging and long slit spectrograph for robotic telescopes

The COmpact LOw REsolution Spectrograph (COLORES) is a compact and lightweight (13 kg) f/8 imaging spectrograph designed for robotic telescopes, now installed and operating on the TELMA, a rapid-slewing 60 cm telescope of the BOOTES-2 observatory in Málaga (Spain). COLORES is a multi-mode instrument that enables the observer to seamlessly switch between low-dispersion spectroscopy and direct imaging modes during an observation. In this paper, we describe the instrument and its development, from the initial scientific requirements through the optical design process to final configuration with theoretical performance calculations. The mechanical and electronic design is described, methods of calibration are discussed and early laboratory and scientific results are shown.

Recent GRBs Observed with the 1.23 m CAHA Telescope and the Status of Its Upgrade

We report on optical observations of Gamma-Ray Bursts (GRBs) followed up by our collaboration with the 1.23 m telescope located at the Calar Alto observatory. The 1.23 m telescope is an old facility, currently undergoing upgrades to enable fully autonomous response to GRB alerts. We discuss the current status of the control system upgrade of the 1.23 m telescope. The upgrade is being done by our group based on the Remote Telescope System, 2nd Version (RTS2), which controls the available instruments and interacts with the EPICS database of Calar Alto. (Our group is called ARAE (Robotic Astronomy & High-Energy Astrophysics) and is based on members of IAA (Instituto de Astrofisica de Andalucia). Currently the ARAE group is responsible to develop the BOOTES network of robotic telescopes (Jelinek et al. 2009).) Currently the telescope can run fully autonomously or under observer supervision using RTS2. The fast reaction response mode for GRB reaction (typically with response times below 3 minutes from the GRB onset) still needs some development and testing. The telescope is usually operated in legacy interactive mode, with periods of supervised autonomous runs under RTS2. We show the preliminary results of several GRBs followed up with observer intervention during the testing phase of the 1.23 m control software upgrade.

A Decade of GRB Follow-Up by BOOTES in Spain (2003–2013)

The authors appreciate the auspices of INTA, IHSM-UMA/CSIC, and UMA as well as the financial support by the Junta de Andaluca and the Spanish Ministry of Economy and Competitiveness through the Research Projects P07-TIC-03094, P12-TIC2839, AYA2009-14000-C03-01, AYA 2010-39727-C03-01, and AYA-2015-71718-R. Martin Jelinek was supported by the postdoctoral fellowship of the Czech Academy of Sciences. This study was carried out in the framework of the Unidad Asociada IAA-CSIC at the Group of Planetary Science of ETSI-UPV/EHU. This work was supported by the Ikerbasque Foundation for Science. The Czech CVUT FEL team acknowledges the support by GA CR Grant 13-33324S.

Follow-up of X-ray transients detected by SWIFT with COLORES using the BOOTES network

The Burst Observer and Optical Transient Exploring System (BOOTES) is a network of telescopes that allows the continuous monitoring of transient astrophysical sources. It was originally devoted to the study of the optical emission from gamma-ray bursts (GRBs) that occur in the Universe. In this paper we show the initial results obtained using the spectrograph COLORES (mounted on BOOTES-2), when observing compact objects of diverse nature.

Operating a global network of autonomous observatories

We discuss our experiences operating a heterogeneous global network of autonomous observatories. The observatories are presently situated on four continents, with a fifth expected during the summer of 2010. The network nodes are small to intermediate diameter telescopes (<= 150 cm) owned by different institutions but running the same observatory control software. We report on the experience gained during construction, commissioning and operation of the observatories, as well as future plans. Problems encountered in the construction and operation of the nodes are summarised. Operational statistics as well as scientific results from the observatories are also presented.