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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). [ABSTRACT FROM AUTHOR]

Fermi-LAT and AGILE have already detected more than 70 rotation-powered pulsars at GeV energies, opening a new era of pulsar physics. In particular, Fermi has unveiled the existence of a large population of Geminga-like pulsars, γ-ray bright but radio-silent. We used XMM-Newton, Chandra and Swift to study such new, γ-ray selected, pulsar population and to compare its X-ray behaviour with that of the radio pulsars. While radio-loud and radio-quiet pulsars need not to be different objects, their different viewing geometry with respect to the observer does influence the ratio between γ and X-ray emissions. When plotting the distance-indipendent γ to X-ray flux ratios as a function of the pulsars' rotational energy losses, one immediately sees that pulsars with similar energetics have Fγ/FX spanning 3 decades. Such spread, most probably stemming from vastly different geometrical configurations of the X and γ-ray emitting regions, defies any straightforward interpretation of the plot. We find that, on average, radio-quiet pulsars do have higher values of Fγ/FX, implying an intrinsec faintness of their X-ray emission and/or a different geometrical configuration. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

AGILE is a small gamma-ray astronomy satellite mission of the Italian Space Agency dedicated to high-energy astrophysics launched in 2007 April. It provides large sky exposure levels (>=109 cm2 s per year on the Galactic Plane) with sensitivity peaking at E∼400 MeV (and simultaneous X-ray monitoring in the 18–60 keV band) where the bulk of pulsar energy output is typically released. Its ∼1 μs is absolute time tagging capability makes it perfectly suited for the study of gamma-ray pulsars following up on the CGRO/EGRET heritage. In this paper we summarize the timing results obtained during the first year of AGILE observations of the known gamma-ray pulsars Vela, Crab, Geminga and B 1706-4. AGILE collected a large number of gamma-ray photons from EGRET pulsars (∼10,000 pulsed counts for Vela) in only few months of observations unveiling new interesting features at sub-millisecond level in the pulsars’ high-energy light-curves and paving the way to the discovery of new gamma-ray pulsars. [ABSTRACT FROM AUTHOR]

The very high energy γ-ray spectra of Pulsar Wind Nebulae are interpreted as due to inverse Compton scattering of ultrarelativistic electrons on the ambient photons, whereas their X-ray spectra are due to synchrotron emission. We investigate the relation between the γ- and X-ray emission and the pulsars’ spin-down luminosity and characteristic age. We find that the γ-to X-ray flux ratio of the nebulae is inversely proportional to the spin-down luminosity (∝Ė-1.9) and to the characteristic age (∝τc2.2) of the parent pulsar. We interpret these results as due to the evolution of the electron energy distribution and the nebular dynamics, supporting the idea of so-called relic pulsar wind nebulae. These empirical relations provide a new tool to classify unidentified diffuse γ-ray sources and to estimate the spin-down luminosity and characteristic age for four rotation powered pulsars with no detected pulsation from the X- and γ—ray properties of the associated pulsar wind nebulae. [ABSTRACT FROM AUTHOR]

GRB070724B is the first Gamma Ray Burst localized by the SuperAGILE instrument aboard the AGILE space mission. The SuperAGILE localization has been confirmed after the after-glow observation by the XRT aboard the Swift satellite. No significant gamma ray emission above 50 MeV has been detected for this GRB. In this paper we describe the SuperAGILE capabilities in detecting Gamma Ray Burst and the AGILE observation of GRB 070724B. [ABSTRACT FROM AUTHOR]

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 detection system on board of the AGILE satellite and report on some early GRB detections. [ABSTRACT FROM AUTHOR]

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. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The AGILE Mission 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 at the beginning of 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. The broadband detection of GRBs and the study of implications for particle acceleration and high energy emission are primary goals of the mission. AGILE can image GRBs with 2–3 arcminute 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 is now (January 2007) undergoing final satellite integration and testing. The PLS V launch is planned in spring 2007. AGILE is then foreseen to be fully operational during the summer of 2007. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

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. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The study of pulsar bow-shocks is one of the most promising ways towards the understanding of the interactions between neutron stars relativistic winds and their environment. These objects are best resolved as Hα nebulae but velocity-driven features are seen also in the radio and X-ray bands and represent interesting targets for future gamma-rays telescopes. We present a preliminary multiwavelength catalogue of pulsar bow-shocks and discuss the prospects for gamma-rays observations with AGILE and GLAST. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The gamma-ray observatory AGILE, the first ASI Small Mission, is planned to operate in 2002-2005. We present here Super-AGILE, an X-ray detector added on top of the gamma-ray tracker. Super-AGILE will have a large field of view, providing hard X-ray imaging and moderate spectroscopy together with the gamma-ray detector. Super-AGILE is composed by Si-microstrip detectors, equipped with a low-noise electronics allowing a sensitive range of 10-40 keV, and coupled with a set of mutually orthogonal one-dimensional coded masks. A bidimensional source location capability is obtained by dividing the total 1444 cm² geometric area of the detectors in two orthogonal directions. [ABSTRACT FROM AUTHOR]

AGILE is an ASI gamma-ray astrophysics space Mission which will operate in the 30 MeV - 30 GeV with imaging capabilities also in the 10-40 keV range. Primary scientific goals include the study of AGNs, gamma-ray bursts, Galactic sources, unidentified gamma-ray sources, diffuse Galactic and extragalactic gamma-ray emission, high-precision timing studies, and Quantum Gravity testing. AGILE will be the only Mission entirely dedicated to source detection above 30 MeV during the period 2003-2006. [ABSTRACT FROM AUTHOR]

The AGILE scientific instrument is based on an innovative design based on three detecting systems: (1) a Silicon Tracker, (2) a Mini-Calorimeter, and (3) an ultralight coded mask system with Si-detectors (Super-AGILE). AGILE is designed to provide: (1) excellent imaging in the energy bands 30 MeV-50 GeV (5-10 arcmin for intense sources) and 10-40 kev (1-3 arcmin);, (2) optimal timing capabilities, with independent readout systems and minimal deadtimes for the Silicon tracker, Super-AGILE and Mini-Calorimeter; (3) large fields of view for the gamma-ray imaging detector (∼3 sr) and Super-AGILE (∼1 sr). [ABSTRACT FROM AUTHOR]

AGILE is an ASI Small Scientific Mission dedicated to high-energy astrophysics. The AGILE instrument is designed to detect and image photons in the 30 MeV-50 GeV and 10-40 keV energy bands, with excellent spatial resolution and timing capability, and an unprecedently large field of view covering ∼ 1/4 of the entire sky at energies above 30 MeV. Primary scientific goals include the study of AGNs,gamma-ray bursts, Galactic sources, unidentified gamma-ray sources, diffuse Galactic and extragalactic gamma-ray emission, high-precision timing studies, and Quantum Gravity testing. The AGILE Science Program will be open to the international scientific community. AGILE is planned to be operational during the year 2002, and will be the only mission entirely dedicated to high-energy astrophysics above 30 MeV to support multiwave-length studies during the period 2002-2005. [ABSTRACT FROM AUTHOR]

We describe the AGILE gamma-ray astronomy satellite which has recently been selected as the first Small Scientific Mission of the Italian Space Agency. With a launch in 2002, AGILE will provide a unique tool for high-energy astrophysics in the 30 MeV–50 GeV range before GLAST. Despite the much smaller weight and dimensions, the scientific performances of AGILE are comparable to those of EGRET. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The spectrometer on INTEGRAL (SPI) is one of the two main telescopes of the future INTEGRAL observatory. SPI is made of a compact hexagonal matrix of 19 high-purity germanium detectors shielded by a massive anticoincidence system. A HURA type coded aperture modulates the astrophysical signal. The spectrometer system, its physical characteristics and performances are presented. The instrument properties such as imaging capability, energy resolution and sensitivity have been evaluated by means of extensive Monte-Carlo simulations. With the expected performances of SPI, it will be possible to explore the γ-ray sky in greater depth and detail than it was possible with previous γ-ray telescopes like SIGMA, OSSE and COMPTEL. In particular, the high-energy resolution will allow for the first time the measurement of γ-ray line profiles. Such lines are emitted by the debris of nucleosynthesis and annihilation processes in our Galaxy. Lines from these processes have already been measured, but due to the relatively poor energy resolution, details of the emission processes in the source regions could not be studied. With the high-resolution spectroscopy of SPI such detailed investigations will be possible. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

AGILE is an innovative, cost-effective gamma-ray mission selected by the Italian Space Agency for a Program of Small Scientific Missions. The AGILE gamma-ray imaging detector (GRID, made of a Silicon tracker and CsI Mini-Calorimeter) is designed to detect and image photons in the 30 MeV–50 GeV energy band with good sensitivity and very large field of view (FOV ∼3 sr). The X-ray detector, Super-AGILE, sensitive in the 10–40 keV band and integrated on top of the GRID gamma-ray tracker will provide imaging (1–3 arcmin) and moderate spectroscopy. For selected sky areas, AGILE might achieve a flux sensitivity (above 100 MeV) better than 5×10[sup -8] ph cm[sup 2] s[sup -1] at the completion of its scientific program. AGILE will operate as an Observatory open to the international community and is planned to be operational during the year 2002 for a nominal 2-year mission. It will be an ideal ‘bridge’ between EGRET and GLAST, and the only mission entirely dedicated to high-energy astrophysics above 30 MeV during that period. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The scientific instrument of the AGILE mission is innovative in many ways. It is an integrated instrument based on three detecting systems: (1) a Silicon Tracker, (2) a Mini-Calorimeter, and (3) an ultralight coded mask system with Si-detectors (Super-AGILE). For a relatively low mass (∼70 kg) and large ratio of expected performance over cost, AGILE is planned to provide (i) Optimal imaging in the energy bands 30 MeV–50 GeV (5–10 arcmin for intense sources) and 10–40 keV (1–3 arcmin). (ii) Optimal timing capabilities, with independent readout systems and minimal dead-times for the Silicon Tracker, Super-AGILE and Mini-Calorimeter. (iii) A very large field of view for the gamma-ray imaging detector (3 sr) and Super-AGILE (1 sr). © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this paper the results of the first months of burst search on very short time scales with the Mini-Calorimeter (MCAL) on-board the AGILE mission are presented. MCAL is equipped with a flexible on-board trigger logic for autonomous GRB detection. In addition to standard trigger time windows, MCAL has been equipped with trigger capabilities on 16 ms, 1 ms and sub-millisecond time windows. Since June 2008 burst search on these short time scales has been enabled, resulting in an average rate of 4 triggers/orbit, compliant with telemetry budget. An on-ground rejection strategy is applied, allowing more sophisticated selection criteria than those allowed by the on-board trigger logic. Triggers due to instrumental effects or geophysical phenomena can be spotted due to their photon-by-photon pattern; what remains after this cleaning is an almost unexplored territory and could shed light on the origin of very short bursts. The trigger criteria, as well as the on-ground rejection strategy and the properties of the selected events will be described and discussed. [ABSTRACT FROM AUTHOR]

We present the first results of our VLT observation campaign of the Central Compact Objects (CCOs) in SNRs RX J085201.4-461753 (Vela Jr), 1E 1648-5051 (RCW 103) and RX J171328.4-394955 (G347.3-0.5). For Vela Jr., we found that the source is embedded in a compact optical nebulosity, possibly a bow-shock or a photo-ionization nebula, and we identified a candidate IR counterpart to the CCO. For RCW 103, we found no convincing evidence neither for 6 hrs IR modulation nor for variability on any time scale from the proposed counterpart, as well as for the other candidates close to the revised Chandra position. For G347.3-0.5, we identified few possible IR counterparts but none of them is apparently associated with the CCO. [ABSTRACT FROM AUTHOR]