Astroparticle Physics at INFN Bari
The astroparticle activities in Bari span a wide variety of topics.
The many different experiments in which local researchers are involved study cosmic rays, neutrinos and high-energy gamma rays. They aim to provide important clues to explain the origin and acceleration of cosmic ray, the matter-antimatter asymmetry in the Universe, the nature of Dark Matter, the mechanisms powering Gamma-Ray Bursts and their connection with Gravitational Waves production, thus contributing to better understand the unresolved mysteries of the Universe.
INFN Astroparticle physics research activities are coordinated by CSN2.
Below you can find a list of international space- and ground-based experiments in which local researchers are currently involved.
HERD High Energy cosmic-Radiation Detection
The High Energy cosmic-Radiation Detection (HERD) facility has been proposed as a space astronomy payload onboard the future China’s Space Station (CSS) aimed to detect charged cosmic-rays and gamma-rays from a few GeV to PeV energies.
The main science objectives of HERD are the search of dark matter particles, the study of the cosmic-ray chemical composition and high energy gamma-ray observations.
HERD will extend high precision and high statistics spectral measurements of individual cosmic-ray species up to a few PeV, reaching the knee of the all-particle spectrum. It will also observe the gamma-ray sky from a few hundred MeV up to 1 TeV contributing to multi-messenger astronomy together with ground-based high-energy gamma-ray telescopes and neutrino and gravitational waves detectors.
In the baseline design, HERD is composed of a 3-D cubic imaging calorimeter (CALO) surrounded by scintillating fiber trackers (FITs) on the top and on the four lateral sides. Then the CALO and FIT are covered by the Silicon Charge Detector (SCD) and the plastic scintillator detector (PSD) from outside.
A Transition Radiation Detector (TRD) is located on the lateral side. SCD is for the accurate measurement of particle absolute charge magnitude |Z|. PSD is for the trigger of LE gamma and charge measurement; FIT is mainly for particle tracking and charge measurement; CALO is for energy reconstruction and e/p discrimination; TRD is for calibration of TeV nuclei.
Local coordinator: Gargano Fabio
KM3NeT is a future European deep-sea research infrastructure hosting a new generation neutrino telescope with a volume of several cubic kilometres that – located at the bottom of the Mediterranean Sea – will open a new window on the Universe. With the telescope scientists of KM3NeT will search for neutrinos from distant astrophysical sources such as supernovae, gamma ray bursters or colliding stars. An array of thousands of optical sensors will detect the faint light in the deep sea from charged particles originating from collisions of the neutrinos and the Earth. The facility will also house instrumentation for Earth and Sea sciences for long term and on-line monitoring of the deep sea environment and the sea bottom at depth of several kilometers.
Local coordinator: Marco Circella
The Fermi Gamma-ray Space Telescope is a space observatory for astrophysical gamma rays in the energy range from 8 keV to a few hundred GeV.
The Fermi satellite is equipped with two instruments: the Gamma-ray Burst Monitor (GBM), which is sensitive to the lower energy range, up to a few tens of MeV and is devoted to the study of transient phenomena, and the Large Area Telescope (LAT), which is sensitive to the higher energy range staring from 20 MeV.
The LAT can also detect the cosmic-ray electrons and positrons with energies above a few GeV.
Fermi is aimed to study the mechanisms of particle acceleration and emission of electromagnetic radiation in local (Sun and celestial bodies), galactic (pulsars, supernova remnants) and extra-galactic sources (Active Galactic Nuclei, galaxies, galaxy clusters, gamma-ray bursts). It is also devoted to the study of unidentified gamma-ray sources and the diffuse galactic and extra-galactic gamma radiation.
In addition, Fermi can indirectly detect dark matter particles when they decay or annihilate with photons or electron-positron pairs in the final states.
Local coordinator: Loparco Francesco
MAGIC Major Atmospheric Gamma Imaging Cherenkov
The present generation of Imaging Atmospheric Cherenkov Telescopes (IACT), H.E.S.S., MAGIC and VERITAS, has in recent years opened the realm of ground-based gamma-ray astronomy in the energy range above a few tens of GeV. This imaging technique relies on the detection on the ground of the images of the Cherenkov light distribution from the electromagnetic cascades generated by the entrance of a gamma-ray in the atmosphere.
The excellent results of this technique are mainly due to the possibility to efficiently differentiate the nature of the primary particles (p/ γ) using the shape of the Cherenkov image. In fact, from the measurement, it is possible to determine the longitudinal and lateral development of the electromagnetic showers, as well as the arrival direction and energy of the primary gamma-rays.
Among the three major IACT systems in operation, a fundamental role is played by the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes, being characterized by the largest collection surface of any existing gamma-ray telescope worldwide, each constituted by nearly 1000 mirrors resulting in a 17 m diameter reflective parabolic dish. The two telescopes, usually operated in coincidence in the so-called stereoscopic mode, are located at 2250 m a.s.l. in the “Observatorio del Roque de los Muchachos” (La Palma, Canary Islands, Spain) and are separated by a distance of 85 meters.
Due to the large surfaces of the telescopes and to the optimal light collection of their mirrors, MAGIC allows the detection of gamma-rays with a lower energy threshold of about 30 GeV. Moreover, with respect to other imaging atmospheric Cherenkov telescopes, this instrument is characterized by a very fast repositioning of the telescope axis, by virtue of its light-weight reinforced-carbon-fiber structure. A key-feature, enabling MAGIC to cooperate with other observatories, e.g. satellite-based wide-angle detectors, in order to follow the emission of short-lived phenomena like Active Galactic Nuclei (AGN) flares and Gamma-Ray Bursts (GRBs) which are among the most luminous sources of electromagnetic radiation known in the Universe.
Local coordinator: Elisabetta Bissaldi
DAMPE DArk Matter Particle Explorer
DAMPE (DArk Matter Particle Explorer) is one of the satellite missions in the framework of the Strategic Pioneer Research Program in Space Science of the Chinese Academy of Sciences (CAS). DAMPE was launched on 17 December 2015 at 08:12 Beijing time into a sun-synchronous orbit at an altitude of 500 km.
DAMPE is a high-precision space telescope for high-energy gamma-ray, electron and cosmic rays detection. It consists of a double layer of plastic scintillator strips detector (PSD) that serves as an anti-coincidence detector, followed by a silicon-tungsten tracker-converter (STK), which is made of 6 tracking double layers; each consists of two layers of single-sided silicon strip detectors measuring the two orthogonal views perpendicular to the pointing direction of the apparatus. Three layers of Tungsten plates with a thickness of 1 mm are inserted in front of tracking layers 2, 3 and 4 for photon conversion. The STK is followed by an imaging calorimeter of about 31 radiation lengths thickness, made up of 14 layers of Bismuth Germanium Oxide (BGO) bars in a hodoscopic arrangement. A layer of neutron detectors is added to the bottom of the calorimeter.
The total thickness of the Bismuth Germanium Oxide calorimeter (BGO) and the STK correspond to about 33 radiation lengths, making it the deepest calorimeter ever used in space. Finally, in order to detect delayed neutrons resulting from hadron shower and to improve the electron/proton separation power, a neutron detector (NUD) is placed just below the calorimeter. The NUD consists of 16 boron-doped plastic scintillator plates, 1 cm thick and 19.5×19.5 cm2 large, each read out by a photomultiplier.
The main scientific objective of DAMPE is to measure electrons and photons with much higher energy resolution and energy range than achievable with existing space experiments, in order to identify possible Dark Matter signatures. It has also great potential in advancing the understanding of the origin and propagation mechanisms of high-energy cosmic rays, as well as in new discoveries in high-energy gamma astronomy. DAMPE has an unprecedented sensitivity and energy range for electrons, photons and cosmic rays (protons and heavy ions). For electrons and photons, the detection range is 5 GeV – 10 TeV, with an energy resolution of about 1.5% at 100 GeV. For cosmic rays, the detection range is 100 GeV – 100 TeV, with an energy resolution better than 40% at 800 GeV. The geometrical factor is about 0.3 m2 sr for electrons and photons, and about 0.2 m2 sr for cosmic rays. The angular resolution is 0.1 at 100 GeV.
Local coordinator: Gargano Fabio
Local coordinator: Francesco Cafagna
T2K is a neutrino experiment designed to investigate how neutrinos change from one flavor to another as they travel (neutrino oscillations). An intense beam of muon neutrinos is generated at the J-PARC nuclear physics site on the East coast of Japan and directed across the country to the Super-Kamiokande neutrino detector in the mountains of western Japan. The beam is monitored before it leaves the J-PARC site, using the near detector ND280, and again at Super-K. The change in the intensity and composition of the beam is used to provide information on the properties of neutrinos.
Local coordinator: Radicioni Emilio
CTA Cherenkov Telescope Array
The Cherenkov Telescope Array (CTA) project is an initiative to build the next generation ground-based very high energy gamma-ray instrument. It will serve as an open observatory to a wide astrophysics community and will provide a deep insight into the non-thermal high-energy universe.
The aims of the CTA can be roughly grouped into three main themes, serving as key science drivers: understanding the origin of cosmic rays and their role in the universe, understanding the nature and variety of particle acceleration around black holes, searching for the ultimate nature of matter and physics beyond the Standard Model. CTA will explore our Universe in depth in Very High Energy (VHE, E > 10 GeV) gamma-rays and will investigate cosmic non-thermal processes, in close cooperation with observatories operating at other wavelength ranges of the electromagnetic (EM) spectrum, and those using other messengers such as cosmic rays and neutrinos. Indeed, CTA will be a key instrument for the EM follow-up of transient events in the VHE range, owing to its unprecedented sensitivity, rapid response, and capability to monitor a large sky area via scan-mode operation.
The CTA Observatory (CTAO) will be composed of more than 100 IACTs spread between two arrays, one in the northern hemisphere, on the site of the “Observatorio del Roque de los Muchachos” (La Palma, Canary Islands, Spain) which already hosts the MAGIC telescopes, and one in the southern hemisphere, less than 10 km southeast of the European Southern Observatory’s (ESO’s) existing Paranal Observatory in the Atacama Desert in Chile; CTAO will be an order of magnitude more sensitive and will have a greater energy coverage (from a few tens of GeV to above 100 TeV) with respect to current IACTs.
The two arrays will consist of a combination of large (LST), medium (MST) and small (SST) size telescopes, covering different energy ranges: less than 100 GeV, 0.1 – 10 TeV and more than 10 TeV, respectively. In particular the northern hemisphere site, where the inner regions of the Milky Way are not visible, will focus on extragalactic targets to be observed in low- and mid-energy ranges. Consequently this array will be implemented with LSTs and MSTs. The southern hemisphere site, with its prime view of the rich central region of our Galaxy, will cover a wider energy range and will necessitate the use of all the three different telescope types.
Local coordinator: Elisabetta Bissaldi