ASTRI, Astrofisica con Specchi a Tecnologia Replicante Italiana,
is a project, led by Italian National Institute of Astrophysics, INAF, of the Italian Ministry of Education, University and Research, MIUR, and the Italian Ministry of Economic Development, MISE. The ASTRI Project is strictly related to the Cherenkov Telescope Array International Observatory.
The Cherenkov Telescope Array (CTA),
will be the largest ground-based observatory operating in the very-high-energy gamma-ray (20 GeV - 300 TeV) range.
It will be based on more than one hundred Imaging Atmospheric Cherenkov Telescopes located in two sites,
one for each hemisphere.
The energy coverage, in the southern CTA array, will extend up to hundreds of TeV thanks to 70 Small Sized Telescopes
(SST) with their primary mirrors of about 4 meters in diameter and large field of view of the order of 9 degrees.
It is proposed that one of the first sets of the CTA SSTs array will be represented by (at least)
nine ASTRI telescopes. The prototype of such telescopes, developed by INAF and named ASTRI SST-2M,
is installed in Italy at the INAF "M.G. Fracastoro" Observing Station located in Serra La Nave,
1735 m a.s.l., on mount Etna.
The ASTRI telescopes are characterized by a dual-mirror optical design based on the
Schwarzschild-Couder (SC) configuration.
The focal-plane camera is curved in order to fit the ideal prescription for the SC design and
the sensors are small size Silicon Photomultipliers (SiPM), read-out by a fast front-end electronics.
The ASTRI telescope prototype installed in Serra La Nave has been developed following an end-to-end approach
that comprises all aspects from the design, construction and implementation of the entire hardware and software
system to the final scientific products. In this respect, the internal and external calibration systems,
control/acquisition hardware and software, data reduction and analysis software,
and data archiving system are being realized in addition to the telescope structure and camera.
All parts of the system have been designed to comply with the CTA requirements.
On 2014 September 24th, we held the
inauguration of the ASTRI SST-2M.
The optical validation of the Schwarzschild Couder dual-mirror design of the ASTRI SST-2M prototype was achieved in
this accomplishment was the first optical demonstration for astronomical telescopes using such a design
(CTA Press Release_ASTRI_optics,
(INAF Press Release_ASTRI_optics).
During the nights of 25 and 26 May 2017, the camera of the ASTRI SST-2M telescope prototype recorded
its first ever Cherenkov light while undergoing technical testing.
Although the camera was not yet fully configured, the ASTRI team was still able to capture its
first Cherenkov light and produce beautiful images of the showers generated by cosmic rays in the Earth's atmosphere
(CTA Press Release_ASTRI_First_Light,
(INAF Press Release_ASTRI_First_Light).
In parallel to its normal activity of revealing gamma events through the emitted Cherenkov light,
the ASTRI camera is also able to produce images of the night sky (generated by the stars and the diffused sky background)
using the method of variance based on the statistical analysis of the variability of the signal detected
in the camera electronics.
The Belt of Orion provided us is the first example of night sky image
obtained by analyzing the ASTRI SST-2M camera variance data, January 2018
(INAF Press Release_ASTRI_Variance_Orion_Belt).
The ASTRI SST-2M prototype is currently completing the overall commissioning before entering the science
verification phase that will performed observing bright TeV sources as Crab Nebula, Mrk421 and Mrk501.
The ASTRI project
is led by the Italian National Institute of Astrophysics (INAF) with the collaboration of a number of
Italian Universities, the Italian National Institute of Nuclear Physics (INFN), Universidade de Sao Paulo in Brazil
and North-West University in South Africa.
The ASTRI Team at IASF-Palermo
The IASF-Palermo personnel is strongly involved in the ASTRI project,
both in the management of the entire programme
and in specific areas as camera, electronics, performance study, end-to-end calibration of the ASTRI
telescopes and scientific related topics as well as in the speaker and publication office.
With different committments and tasks, the following
IASF-Palermo personnel is nowadays active part of the ASTRI Collaboration:
Osvaldo Catalano |
Milvia Capalbi |
Giancarlo Cusumano |
Antonino D'Ai' |
Melania Del Santo |
Salvo Giarrusso |
Domenico Impiombato |
Nino La Barbera |
Valentina La Parola ||
Giovanni La Rosa |
Maria Concetta Maccarone |
Antonio Pagliaro |
Bruno Sacco |
Alberto Segreto |
Benedetto Biondo |
Giacomo Fazio ||
Carmelo Gargano |
Francesco Russo |
Osvaldo.Catalano at iasf-palermo.inaf.it
Several technical papers discuss the ASTRI project and its development.
A selection of these is downloadable from the
Official ASTRI Web