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AGILE is a Scientific Mission dedicated to high‐energy astrophysics supported by ASI with scientific participation of INAF and INFN. The AGILE instrument is designed to simultaneously detect and image photons in the 30 MeV – 50 GeV and 15 – 45 keV energy bands with excellent imaging and timing capabilities, and a large field of view covering ∼ 1/5 of the entire sky at energies above 30 MeV. A CsI calorimeter is capable of GRB triggering in the energy band 0.3–50 MeV. The broadband detection of GRBs and the study of implications for particle acceleration and high energy emission are primary goals of th emission. AGILE can image GRBs with 2–3 arcminutes error boxes in the hard X‐ray range, and provide broadband photon‐by photon detection in the 15–45 keV, 03–50 MeV, and 30 MeV–30 GeV energy ranges. Microsecond on‐board photon tagging and a ∼ 100 microsecond gamma‐ray detection deadtime will be crucial for fast GRB timing. On‐board calculated GRB coordinates and energy fluxes will be quickly transmitted to the ground by an ORBCOMM transceiver. AGILE have recently (December 2005) completed its gamma‐ray calibration. It is now (January 2006) undergoing satellite integration and testing. The PLSV launch is planned in early 2006. AGILE is then foreseen to be fully operational during the summer of 2006. It will be the only mission entirely dedicated to high‐energy astrophysics above 30 MeV during the period mid‐2006/mid‐2007.

The AGILE satellite, in orbit since 2007, is localizing about 0.5 GRBs per month with the hard X‐ray imager SuperAGILE (18–60 keV) and is detecting around 1 GRB per week with the non‐imaging Minicalorimeter (0.35–100 MeV). Up to now the AGILE Gamma Ray Imaging Detector firmly detected four GRBs in the energy band between 20 MeV and few GeV. In this presentation we review the status of the GRBs observation with AGILE, we discuss the upper limits in the gamma‐ray band of the non‐detected events and we show some interesting bursts, especially GRB 090618 (bright in soft and hard‐X rays, optical and radio but lacking GeV emission) and GRB 100724B (with a bright GeV emission simultaneous to hard‐X rays without delayed onset).

PKS 1510–089 is a Flat Spectrum Radio Quasar at z = 0.361 with radiative output dominated by the γ‐ray component and high variability over the whole electromagnetic spectrum. In particular, in the last two years very high γ‐ray activity was detected by AGILE with flaring episodes in August 2007 and March 2008 and an extraordinary activity during March 2009. Observations in optical/UV seems to indicate the presence of Seyfert‐like features in the broad band spectrum of PKS 1510–089, such as the little and big blue bumps. Moreover, X‐ray observations in March 2008 show a harder‐when‐brighter behaviour quite rare in FSRQs. We present the multiwavelength data of PKS 1510–089 collected by GASP‐WEBT, REM, Swift and AGILE during these γ‐ray flares.

During the first year of observations, AGILE detected several blazars at high significance: 3 C 279, 3C 454.3, PKS 1510‐089, S5 0716+714, 3 C 273, MKN 421, and W Comae. We obtained long‐term coverage of the Crazy Diamond 3 C 454.3, for more than 100 days at energies above 100 MeV. 3 C 273 was the first blazar detected simultaneously by the AGILE gamma‐ray imaging detector and by its hard X‐ray monitor. S5 0716+714, an intermediate BL Lac object, exhibited a very fast and intense gamma‐ray transient event during an optical high‐state phase, while MKN 421 and W Comae where detected during an AGILE target of opportunity (ToO) repointing. Thanks to the rapid dissemination of our alerts, we were able to obtain multi‐wavelength ToO data from other observatories such as Spitzer, Swift, INTEGRAL, RXTE, Suzaku, MAGIC, VERITAS, as well as optical coverage by means of the WEBT Consortium and REM.

The AGILE Satellite [8] [9], launched the 23rd April 2007, is an italian mission devoted to high energy gamma‐ray astrophysics in the 30 MeV–50 GeV range, with a window in the hard‐X domain 18–60 keV. One of the on‐board detectors, the Mini‐Calorimeter (MCAL), was also designed to work as all sky transient monitor in the energy range 0.33–100 MeV. Though the main purpose of MCAL is the detection of cosmological Gamma‐Ray‐Bursts (GRB), MCAL detected transient events with a very brief duration, few msec, that does not match timing and spectral features of known cosmic GRB. These events more likely agree with the features of typical Terrestrial Gamma‐Ray Flashes as described in the literature and previously detected by the BATSE instrument onboard the Compton Gamma Ray Observatory and the RHESSI satellite. The characteristics of the detected TGF candidate events, as well as their geographical distribution will be presented and discussed.

We present here a concept for a light and low‐power wide field monitor working in the X‐ray range, suitable for simultaneous imaging of large portions of the sky and GRB localizations. Our concept evolves from and improves on the design of the 5‐kg SuperAGILE experiment, flying on the AGILE mission and currently delivering arcmin‐localizations of GRBs at a rate of about 1/month. Similar to SuperAGILE, our concept is based on position sensitive silicon detectors equipped with one‐dimensional coded masks. Different options are available for the detector, whose properties, combined with the scientific requirements, drive the design of the experiment. Our approach is based on a modular detector. The experiment design can then be tailored to specific scientific goals of the experiment or the mission (e.g., to cite GRBs only: the brightest GRBs/XRFs on a large field of view—FoV, or many low‐fluence GRBs/XRFs on a smaller FoV, or the low energy spectrum of the prompt event, or the detection of high‐z GRBs). In this paper we describe the concept, the main detector properties and outline some possible experiment configurations, with examples of their expected performance. Different experiment configurations in terms of area, FoV, angular resolution may be designed starting from the same detectors. Instead, the band‐pass is mostly related to the detector properties. A key point of our project is the high degree of readiness of the detectors that are at production level and may be immediately proposed for a future experiment onboard missions with high readiness requirements.

AGILE is an ASI high‐energy astrophysics mission dedicated to the observation of the Universe. The satellite was successfully launched on April 23, 2007 to a quasi equatorial low‐background orbit. The AGILE instrument is very compact and light (∼100 kg): a gamma‐ray imager (sensitive in the energy band 30 MeV–50 GeV) is the central part of the instrument that includes also a light hard X‐ray imager (18–60 keV) positioned on top of the instrument, and an omnidirectional Calorimeter (350 keV–100 MeV). AGILE is aimed at the study of the most energetic phenomena of our Universe including AGNs, GRBs, Galactic sources and transients. For the first time in gamma‐ray astrophysics, AGILE reaches a field of view of about 3 sr with excellent angular resolution and good sensitivity. The unique combination of a hard X‐ray imager and a gamma‐ray imager is ideal for GRB and transient studies that constitute a crucial part of the AGILE scientific program. We summarize here the main characteristics of the GRB broad‐band d...

We present AGILE results on gamma‐ray blazars. During the first year of observations, AGILE detected seven blazars at high significance: 3C 279, 3C 454.3, PKS 1510‐089, S5 0716+714, 3C 273, MKN 421, and W Comae. We obtained long‐term coverage of the crazy diamond 3C 454.3, for a total of about 3 months at energies above 100 MeV. 3C 273 was the first blazar detected simultaneously by the AGILE gamma‐ray detector and by its hard X‐ray monitor. S5 0716+714, an intermediate BL Lac object, exhibited a very fast and intense gamma‐ray transient during an optical high‐state phase, while MKN 421 and W Comae where detected during an AGILE target of opportunity repointing. Thanks to the rapid dissemination of our alerts, we were able to obtain multi‐wavelength ToO data from other observatories such as Spitzer, Swift, INTEGRAL, RXTE, Suzaku, MAGIC, VERITAS, as well as optical coverage by means of the WEBT Consortium and REM.

AGILE will explore the gamma‐ray Universe with a very innovative instrument combining for the first time a gamma‐ray imager and a hard X‐ray imager. AGILE will be operational in spring 2007 and it will provide crucial data for the study of Active Galactic Nuclei, Gamma‐Ray Bursts, unidentified gamma‐ray sources. Galactic compact objects, supernova remnants, TeV sources, and fundamental physics by microsecond timing. The AGILE instrument is designed to simultaneously detect and image photons in the 30 MeV – 50 GeV and 15 – 45 keV energy bands with excellent imaging and timing capabilities, and a large field of view covering ∼ 1/5 of the entire sky at energies above 30 MeV. A CsI calorimeter is capable of GRB triggering in the energy band 0.3–50 MeV AGILE is now (March 2007) undergoing launcher integration and testing. The PLSV launch is planned in spring 2007. AGILE is then foreseen to be fully operational during the summer of 2007.