125535688
Cosmic Ray, Beam-Halo and Beam-Gas Rate Studies for ATLAS Commissioning
16422857
Preparing for LHC data-taking with the ATLAS experiment
The status of the ATLAS experiment a few months before the start-up of LHC operation is described. Emphasis is given to the preparation for the imminent data-taking phase through commissioning studies with cosmics data. A few examples of the physics potential and goals with early LHC data are also presented.
118222129
Final Report of the Simulation Optimization Task Force
This is the final report of the ATLAS Simulation Optimization Task Force, establishedin June of 2007. This note justifies the selected Geant4 version, physics list, and range cuts to be used by the default ATLAS simulation for initial data taking and beyond. The current status of several projects, including detector description, simulation validation, studies of additional Geant4 parameters, and cavern background, are reported.
126272154
Tagging of low-pt electrons from b decays with the ATLAS electromagnetic calorimeter
14248170
Impact of energy and luminosity upgrades at LHC on the physics programme of ATLAS
The impact of possible LHC upgrades on the physics capabilities of the ATLAS detector is discussed. As a benchmark, an increase in the luminosity by a factor of 10 is considered. For comparison, the doubling of the LHC energy is also explored. Both upgrades significantly enhance the physics capabilities of ATLAS. Measured in terms of the mass reach for new particles, the energy upgrade is more powerful. However, in cases where the effect of an upgrade is to increase the precision of measurements as a result of larger data samples, the luminosity upgrade can be at least as powerful. The pile-up of minimum bias events at higher luminosity could limit the physics performance of ATLAS in areas where tagging of forward jets is needed.
62297467
Status of the ATLAS calorimetry simulation for the TP in DICE
118532651
AGILE Observations of Terrestrial Gamma-Ray Flashes
The AGILE satellite, operating since mid 2007 and primarily devoted to high-energy astrophysics,is one of the only three currently operating space instruments capable of detecting TerrestrialGamma-Ray Flashes (TGFs), together with RHESSI and Fermi-GBM. Thanks to the AGILEMini-Calorimeter instrument energy range extended up to 100MeV and its ﬂexible trigger logic onsub-millisecond time scales, AGILE is detecting more than 10 TGFs/month, adding a wealth ofobservations which pose severe constrains on production models. The main AGILE discoveries inTGF science during two and a half years of observations are the following: 1) the TGF spectrumextends well above 40 MeV, 2) the high energy tail of the TGF spectrum is harder than expectedand cannot be easily explained by previous theoretical models, 3) TGFs can be localized from spaceusing high-energy photons detected by the AGILE gamma-ray imaging detector. In this presenta-tion we will describe the characteristics of the 2.5-years AGILE TGF sample, focusing on the recentresults concerning the TGF high-energy spectral characteristics.I. INTRODUCTION
120972663
The Mini-Calorimeter on-board AGILE: The first year in space
AGILE, the Italian space mission dedicated to gamma-ray and hard-X astrophysics, was successfully launched on 23rd April 2007 and is currently fully operative. The Mini-Calorimeter (MCAL) on-board the AGILE satellite is a scintillation detector made of 20 kg of segmented CsI(Tl) scintillator with photodiode readout with a total geometrical area of 1400 cm2. MCAL can work both as a slave of the AGILE Silicon tracker and as an independent detector for gamma-ray bursts (GRB) detection in the 300 keV - 100 MeV energy range. Despite its limited thickness, due to weight constraints, MCAL has proven to successfully self-trigger GRBs at MeV energies providing photon-by-photon data with less than 2 μs time resolution and almost all-sky detection capabilities. The instrument design and characteristics, as well as the in-flight performance after one year of operation in space and the scientific results obtained so far are reviewed and discussed.
107972078
The Test Equipment of the AGILE Minicalorimeter Prototype
AGILE is an ASI (Italian Space Agency) Small Space Mission for high energy astrophysics in the range 30 MeV – 50 GeV. The AGILE satellite is currently in the C phase and is planned to be launched in 2005. The Payload shall consist of a Tungsten‐Silicon Tracker, a CsI Minicalorimeter, an anticoincidence system and a X‐Ray detector sensitive in the 10–40 KeV range. The purpose of the Minicalorimeter (MCAL) is twofold. It shall work in conjunction with the Tracker in order to evaluate the energy of the interacting photons, and it shall operate autonomously in the energy range 250KeV–250 MeV for detection of transients and gamma ray burst events and for the measurement of gamma ray background fluctuations. We present the architecture of the Test Equipment we have designed and developed in order to test and verify the MCAL Simplified Electrical Model prototype which has been manufactured in order to validate the design of the MCAL Proto Flight Model.
122794211
AGILE, a satellite for high energy γ-ray astrophysics: prospects for the Mini-Calorimeter
AGILE is an ASI (Italian Space Agency) small space mission for high energy astrophysics in the gamma ray energy range 30MeV–50GeV, and in the X-ray band 10keV–40keV. AGILE is composed of three scientific detectors: a TungstenSilicon Tracker, a CsI Mini-Calorimeter and a Silicon based X-ray detector (Super-Agile), moreover an anticoincidence system carries out background rejection. The satellite’s payload will have good imaging performances (with angular resolution of a few arc-minutes in the gamma ray band), good timing resolution and a large field of view (about 1/5 of the sky). AGILE detection principle is based on the pair production process that arises from the interaction between high energy photons and the Tungsten layers of the Silicon Tracker. The Silicon Tracker is designed to determine the direction of the incoming radiation, while the Mini-Calorimeter evaluates the energy of the interacting photons. The Mini-Calorimeter can also work as a stand-alone gamma ray detector in the energy range 250keV–250MeV, with no imaging capabilities, for the detection of transients and gamma ray burst events (in cooperation with Super-Agile) and for the evaluation of gamma ray background fluctuations. In this paper a description of the Mini-Calorimeter is done.
109815200
Test campaign of the mini-calorimeter for the AGILE satellite
The AGILE Mini-Calorimeter (MCAL, with total on-axis radiation length 1.5 X0) comprises 2 orthogonal planes each consisting of 16 CsI(Tl) bars. Its primary purpose is the energy determination of gamma-rays detected by the Gamma-Ray Imaging Detector (GRID) Tracker (energy range 30 MeV–50 GeV). In addition, the MCAL is capable of independently triggering and detecting gamma-ray bursts and other impulsive events in the energy range 0.25–250 MeV. A MCAL prototype, comprising 8 CsI(Tl) detector elements, was tested both with laboratory sources and with charged particles (p=1 GeV/c) during an AGILE Beam Test carried out in November 2000 at the CERN T11 beamline (East Hall, CERN PS). The test setup included a prototype of the electronic chain. A prototype of the digital data acquisition chain, which will be the baseline of the payload Electronic Ground Support Equipment, was also built and tested. We present the preliminary results of this test campaign dedicated to characterizing the detector unit and electronics.