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Bootes-IR (Castro-Tirado et al. 2005) is a robotic observatory based around a 60 cm alt-az telescope (dubbed T60) that can slew rapidly while carrying heavy instrumentation at the Nasmyth loci. Initially commissioned with an optical camera, with which the optical afterglow to GRB 060707 (http://gcn. gsfc. nasa. gov/gcn3/5290.gcn3) was discovered, we have concentrated our efforts on the near-IR (0.8-2.5 µm) camera (BIRCAM) for which the telescope was specifically designed. The telescope is installed at the Observatorio de Sierra Nevada near Granada in Spain, at an altitude of 3000 m and in an area of very low humidity. The telescope, dome, camera and liquid nitrogen generation and refilling systems have all been recently brought back into operation, and routine observations are expected to begin within the next few months. [ABSTRACT FROM AUTHOR]

We summarize the results of our programs started in 2009 with the 10.4 m Gran Telescopio Canarias (GTC) telescope. Since then its instruments have been subject of a continuous upgrade, making the GTC a competitive telescope for the GRB field. So far (Dec. 2012) the GTC have followed up 25 GRBs, measuring 10 redshifts, and discovering two SNe associated to GRBs. The new generation of instruments foreseen for the coming years will contribute substantially to enhance the knowledge of these puzzling explosions. [ABSTRACT FROM AUTHOR]

Since the early 90s Gamma Ray Bursts have been accepted to be of extra-galactic origin thanks to the isotropic distribution observed by BATSE and the redshifts observed in some of their optical or infrared counterparts. Nevertheless, there have been a few cases that upon further examination have turned out to be of galactic origin. Several of these galactic sources have presented a Fast Rise, Exponential Decay structure which leads us to believe that there could be an underlying correlation. In this work we do several statistical analyses to determine the degree of contamination by galactic sources that certain subsample of known FREDs have. And find that certain subsamples have a most probable contamination between 27% and 34%. [ABSTRACT FROM AUTHOR]

The Ultra-Fast Flash Observatory (UFFO) is a space observatory for optical follow-ups of gamma ray bursts (GRBs), aiming to explore the first 60 seconds of GRBs optical emission. UFFO is utilized to catch early optical emissions from GRBs within few sec after trigger using a Gimbal mirror which redirects the optical path rather than slewing entire spacecraft. We have developed a 15 cm two-axis Gimbal mirror stage for the UFFO-Pathfinder which is going to be on board the Lomonosov satellite which is to be launched in 2013. The stage is designed for fast and accurate motion with given budgets of 3 kg of mass and 3 Watt of power. By employing stepping motors, the slewing mirror can rotate faster than 15 deg/sec so that objects in the UFFO coverage (60 deg x 60 deg) can be targeted in ~1 sec. The obtained targeting resolution is better 2 arcmin using a close-loop control with high precision rotary encoder. In this presentation, we will discuss details of design, manufacturing, space qualification tests, as well as performance tests. [ABSTRACT FROM AUTHOR]

The Ultra-Fast Flash Observatory (UFFO) Pathfinder for Gamma-Ray Bursts (GRBs) consists of two telescopes. The UFFO Burst Alert & Trigger Telescope (UBAT) handles the detection and localization of GRBs, and the Slewing Mirror Telescope (SMT) conducts the measurement of the UV/optical afterglow. UBAT is equipped with an X-ray detector, analog and digital signal readout electronics that detects X-rays from GRBs and determines the location. SMT is equipped with a stepping motor and the associated electronics to rotate the slewing mirror targeting the GRBs identified by UBAT. First the slewing mirror points to a GRB, then SMT obtains the optical image of the GRB using the intensified CCD and its readout electronics. The UFFO Data Acquisition system (UDAQ) is responsible for the overall function and operation of the observatory and the communication with the satellite main processor. In this paper we present the design and implementation of the electronics of UBAT and SMT as well as the architecture and implementation of UDAQ. [ABSTRACT FROM AUTHOR]

The Slewing Mirror Telescope (SMT) is the UV/optical telescope of UFFO-pathfinder. The SMT optical system is a Ritchey- Chrétien (RC) telescope of 100 mm diameter pointed by means of a gimbal-mounted fiat mirror in front of the telescope. The RC telescope has a 17 x 17 arcmin² in Field of View and 4.3 arcsec resolution (full width half maximum of the point spread function) The beam-steering mirror enables the SMT to access a 35 x 35 degree region and point and settle within 1 sec. All mirrors were fabricated to about 0.02 wave-lengths RMS in wave front error (WFE) and 84.7% average reflectivity over 200 nm ~ 650 nm. The RC telescope was aligned to 0.05 wave- lengths RMS in WFE (test wavelength 632.8 nm). In this paper, the technical details of the RC telescope and slewing mirror system assembly, integration, and testing are given shortly, and performance tests of the full SMT optical system are reported. [ABSTRACT FROM AUTHOR]

The Ultra-Fast Flash Observatory (UFFO) aims to detect the earliest moment of Gamma-Ray Bursts (GRBs) which is not well known, resulting into the enhancement of GRB mechanism understanding. The pathfinder mission was proposed to be a scaled-down version of UFFO, and only contains the UFFO Burst Alert & Trigger Telescope (UBAT) measuring the X-ray/gamma-ray with the wide-field of view and the Slewing Mirror Telescope (SMT) with a rapid-response for the UV/optical photons. Once the UBAT detects a GRB candidate with the position accuracy of 10 arcmin, the SMT steers the UV/optical photons from the candidate to the telescope by the fast rotatable mirror and provides the early UV/optical photons measurements with 4 arcsec accuracy. The SMT has a modified Ritchey-Chrètien telescope with the aperture size of 10 cm diameter including the rotatable mirror and the image readout by the intensified charge-coupled device. There is a key board called the UFFO Data Acquisition system (UDAQ) that manages the communication of each telescope and also of the satellite and the UFFO overall operation. This pathfinder is designed and built within the limited size and weight of ~20 kg and the low power con- sumption up to ~30 W. We will discuss the design and performance of the UFFO-pathfinder, and its integration to the Lomonosov satellite. [ABSTRACT FROM AUTHOR]

The UFFO (Ultra-Fast Flash Observatory) is a GRB detector on board the Lomonosov satellite, to be launched in 2013. The GRB trigger is provided by an X-ray detector, called UBAT (UFFO Burst Alarm & Trigger Telescope), which detects X-rays from the GRB and then triggers to determine the direction of the GRB and then alerts the Slewing Mirror Telescope (SMT) to turn in the direction of the GRB and record the optical photon fluxes. This report details the calibration of the two components: the MAPMTs and the YSO crystals and simulations of the UBAT. The results shows that this design can observe a GRB within a field of view of ±35° and can trigger in a time scale as short as 0.2 - 1.0 s after the appearance of a GRB X-ray spike. [ABSTRACT FROM AUTHOR]

One of the unexplored domains in the study of gamma-ray bursts (GRBs) is the early time phase of the optical light curve. We have proposed Ultra-Fast Flash Observatory (UFFO) to address this question through extraordinary opportunities presented by a series of small space missions. The UFFO is equipped with a fast-response Slewing Mirror Telescope that uses a rapidly moving mirror or mirror array to redirect the optical beam rather than slewing the entire space-craft or telescope to aim the optical instrument at the GRB position. The UFFO will probe the early optical rise of GRBs with sub-second response, for the first time, opening a completely new frontier in GRB and transient studies. Its fast response measurements of the optical emission of dozens of GRB each year will provide unique probes of the burst mechanism and test the prospect of GRB as a new standard candle, potentially opening up the z > 10 universe. We describe the current limit in early photon measurements, the aspects of early photon physics, our soon-to-be-launched UFFO-pathfinder mission, and our next planned mission, the UFFO-100. [ABSTRACT FROM AUTHOR]

We present the results from an optical monitoring campaign aimed at studying the afterglow properties of the short GRB 100816A. We implemented a new way of processing the Swift-BAT data, and based on it we reclassified this burst as short, discarding the initial classification as long. Observations were carried out mainly with the GTC Telescope within the four following days after the burst to investigate the optical photometry of its afterglow, and a year later to localize the host. We completed the optical imaging with the 1.23 m and 3.5 m CAHA Telescopes. We built and fitted the nIR-optical SED for the characterization of the host. The best fit of the SED (χ²/d.o.f. = 1.656) obtained for assumed values of a solar metallicity, and an extinction of AV = 0.2 mag is obtained for a starburst galaxy with a dominant stellar population aging about 360 Myr. [ABSTRACT FROM AUTHOR]

Since 1997, and following our detection of the first mm afterglow, we have followed-up 70 GRBs, mainly with the IRAM's Plateau de Bure Interferometer, what can be considered as the IRAM Legacy GRB Sample. 66 events were observed at 3 mm, with 19 of them being detected (with another 3 having marginal detections). 32 GRBs were followed up at 1 mm, with 6 of them being detected. Redshifts for the GRB afterglows lie in the range z = 0.03-8.3, with measured flux densities (at 3 mm) varying between 0.25 and 60 mJy (but usually < 1.5 mJy) with first observations taking place around 1 2 days after the GRB. Forward shock emission expleains the observations with the exception of one particular case (GRB 090423 at z = 8.2) for which reverse shock emission is required. [ABSTRACT FROM AUTHOR]

The Ultra-Fast Flash Observatory (UFFO), which will be launched onboard the Lomonosov spacecraft, contains two crucial instruments: UFFO Burst Alert & Trigger Telescope (UBAT) for detection and localization of Gamma-Ray Bursts (GRBs) and the fast-response Slewing Mirror Telescope (SMT) designed for the observation of the prompt optical/UV counterparts. Here we discuss the in-space calibrations of the UBAT detector and SMT telescope. After the launch, the observations of the standard X-ray sources such as pulsar in Crab nebula will provide data for necessary calibrations of UBAT. Several standard stars will be used for the photometric calibration of SMT. The celestial X-ray sources, e.g. X-ray binaries with bright optical sources in their close angular vicinity will serve for the cross-calibration of UBAT and SMT. [ABSTRACT FROM AUTHOR]

BOOTES-1B and BOOTES-2 were first to follow-up the Swift GRB 080605. Observations started 44s after the GRB trigger, discovering the optical afterglow with the brightness of R = 14.7. A power-law decay with an α = 1.27 ± 0.04 was observed during the first ~600 s after the trigger. [ABSTRACT FROM AUTHOR]

GRB 110715A had a bright afterglow that was obscured in the optical by a high Galactic extinction. We discovered the submillimeter counterpart with APEX and followed it in radio with ATCA for over 2 months. Additional submm observations were performed with ALMA as a test of the ToO procedures during commissioning, becoming the first GRB afterglow to be detected by the observatory. UV, optical and NIR observations were performed with Swift/UVOT and 2.2 m/GROND in La Silla and X-ray data were obtained by Swift/XRT. The dataset is complemented with spectroscopic data from the VLT/X-shooter spectrograph. The absorption features present in the intermediate resolution optical/nIR spectra reveal a redshift of 0.8224 and a host galaxy environment with low ionization. We fit in the host galaxy absorption features two velocity components separated by 30 km/s, implying a host galaxy with low dynamical activity. [ABSTRACT FROM AUTHOR]

An introduction to this issue of "EAS Publications Series," in which the authors discuss research studies in the gamma-ray which were published in this Volume of the European Astronomical Society Conference Series.