The birth of gravitational-wave / electromagnetic astronomy was heralded by the joint observation of gravitational waves (GWs) from a binary neutron star (BNS) merger by Advanced LIGO and Advanced Virgo, GW170817, and of gamma-rays from the short gamma-ray burst GRB170817A by the Fermi Gamma-ray Burst Monitor (GBM) and INTEGRAL. This detection provided the first direct evidence that at least a fraction of BNSs are progenitors of short GRBs. GRBs are now also known to emit very-high-energy (VHE, > 100 GeV) photons as has been shown by recent independent detections of the GRBs 1901114C and 180720B by the ground-based gamma-ray detectors MAGIC and H.E.S.S. In the next years, the Cherenkov Telescope Array (CTA) will boost the searches for VHE counterparts thanks to its unprecedented sensitivity, rapid response and capability to monitor large sky areas via survey-mode operation. In this contribution, we present the CTA program of observations following the detection of GW events. We discuss various follow-up strategies and links to multi-wavelength and multi-messenger observations. Finally we outline the capabilities and prospects of detecting VHE emission from GW counterparts.
List of contributions from the Cherenkov Telescope Array (CTA) Consortium presented at the 36th International Cosmic Ray Conference, July 24 - August 1 2019, Madison, WI, EUA.
We discuss the potential for the detection of dark matter and the characterization of its particle nature via the observation of dark matter subhalos. Specifically, we discuss the search for dark matter Galactic subhalos in the gamma-ray band with the Large Area Telescope on-board the Fermi gamma-ray Space Telescope, and the future generation of imaging atmospheric Cherenkov telescopes, best represented by the planned Cherenkov Telescope Array.
Misaligned AGN (MAGNs), i.e., radio-loud AGNs with the jet not pointing directly towards us, represent a new class of GeV emitters revealed by the Fermi space telescope. Although they comprise only a small fraction of the high-energy sources, MAGNs are extremely interesting objects offering a different perspective to study high-energy processes with respect to blazars. The aim of this work is to evaluate the impact of the new-generation Cherenkov Telescope Array (CTA) on the MAGN class and propose possible observational strategies to optimize their detection.
The Cherenkov Telescope Array is expected to lead to the detection of many new supernova remnants in the TeV and multi-TeV range. In addition to the individual study of each SNR, the study of these objects as a population can help constraining the parameters describing the acceleration of particles and increasing our understanding of the mechanisms involved. We present Monte Carlo simulations of the population of Galactic SNRs emitting TeV gamma rays. We also discuss how the simulated population can be confronted with future observations to provide a novel test for the SNR hypothesis of cosmic…
The current generation of Imaging Atmospheric Cherenkov Telescopes (IACTs), including the H.E.S.S., MAGIC, and VERITAS telescope arrays, have made substantial contributions to our knowledge about the structure and composition of the highly relativistic jets from Active Galactic Nuclei (AGNs). In this paper, we discuss some of the outstanding scientific questions and give a qualitative overview of AGN related science topics which will be explored with the next-generation Cherenkov Telescope Array (CTA). CTA is expected to further constrain the structure and make-up of jets, and thus, to constra…
The First Fermi-LAT catalog (1FGL) represents the most complete list of sources in the GeV sky to date. We use the reported 1FGL spectral parameters to extrapolate Fermi AGN spectra to the very-high energy (VHE) range (15 GeV - 300 TeV). The extrapolated VHE spectra are then attenuated using current estimations of the extragalactic background light (EBL) absorption as a function of redshift. Using the expected effective areas and background rates of the Cherenkov Telescope Array (CTA) from Monte Carlo simulations, we make a first order prediction of the AGN population accessible to CTA in the …
Here the results of calculations of pulses in Cherenkov light detectors for the Yakutsk array are presented. As long as the Vavilov-Cherenkov light is used to calibrate signals in scintillation detectors at the Yakutsk array it is vital for these measurements to be precise. The validity of measurements of the signal Q(400) used as the estimation parameter at the Yakutsk array has been confirmed. Our calculations show that the width of time pulses increases from nearly 50 ns at a distance of 100 m from the shower axis up to 700 ns at 1000 m.
Several types of Galactic sources, like magnetars, microquasars, novae or pulsar wind nebulae flares, display transient emission in the X-ray band. Some of these sources have also shown emission at MeV--GeV energies. However, none of these Galactic transients have ever been detected in the very-high-energy (VHE; E$>$100 GeV) regime by any Imaging Air Cherenkov Telescope (IACT). The Galactic Transient task force is a part of the Transient Working group of the Cherenkov Telescope Array (CTA) Consortium. The task force investigates the prospects of detecting the VHE counterpart of such sources, a…
The Cherenkov Telescope Array (CTA) observatory will probe the non-thermal universe above 20 GeV up to several hundreds of TeV with a significant improvement in sensitivity and angular resolution compared to current experiments. Its outstanding capabilities will allow to increase the number of extragalactic cosmic accelerators detected at very high energy (VHE) and therefore to better constrain the population of VHE accelerators and the gamma-ray absorption processes in the intergalactic medium. For the first time in the history of imaging atmospheric Cherenkov telescopes (IACTs), CTA will be …
Supernova remnants are often presented as the most probable sources of Galactic cosmic rays. This idea is supported by the accumulation of evidence that particle acceleration is happening at supernova remnant shocks. Observations in the TeV range have especially contributed to increase the understanding of the mechanisms, but many aspects of the particle acceleration at supernova remnant shocks are still debated. The Cherenkov telescope array is expected to lead to the detection of many new supernova remnants in the TeV and multi-TeV range. In addition to the individual study of each, the stud…
In the last few years, the Fermi-LAT telescope has discovered over a 100 pulsars at energies above 100 MeV, increasing the number of known gamma-ray pulsars by an order of magnitude. In parallel, imaging Cherenkov telescopes, such as MAGIC and VERITAS, have detected for the first time VHE pulsed gamma-rays from the Crab pulsar. Such detections have revealed that the Crab VHE spectrum follows a power-law up to at least 400 GeV, challenging most theoretical models, and opening wide possibilities of detecting more pulsars from the ground with the future Cherenkov Telescope Array (CTA). In this co…
Data collected by the H.E.S.S. array between 2004 and 2012 have been used to search for photon bursts from primordial black hole explosions. Bursts were searched for in a 30 second time-window. The duration of the search window has been optimized to increase the burst signal while keeping the statistical background low. No evidence for a burst signal was found. Preliminary upper limits on the local rate of PBH explosions of $1.4\times 10^{4} {pc}^{-3} {yr}^{-1}$ have been obtained, which improve previously published limits by almost an order of magnitude
The current generation of Imaging Atmospheric telescopes (IACTs) has demonstrated the power of the technique in an energy range between ~100 GeV up to several tens of TeV. At the high-energy end, these instruments are limited by photon statistics. Future arrays of IACTs such as CTA or AGIS are planned to push into the energy range beyond 100 TeV. Scientifically, this region is very promising, providing a probe of particles up to the 'knee' in the cosmic ray spectrum and access to an unexplored region in the spectra of nearby extragalactic sources. We present first results from our simulation s…
A new EAS Cherenkov light array, Tunka-133, with ~1 km^2 geometrical area has been installed at the Tunka Valley (50 km from Lake Baikal) in 2009. The array permits a detailed study of cosmic ray energy spectrum and mass composition in the energy range 10^16 - 10^18 eV with a uniform method. We describe the array construction, DAQ and methods of the array calibration.The method of energy reconstruction and absolute calibration of measurements are discussed. The analysis of spatial and time structure of EAS Cherenkov light allows to estimate the depth of the EAS maximum X_max. The results on th…
Our Galaxy is filled with cosmic-ray particles and more than 98% of them are atomic nuclei. In order to clarify their origin and acceleration mechanism, chemical composition measurements of these cosmic rays with wide energy coverage play an important role. Imaging Atmospheric Cherenkov Telescope (IACT) arrays are designed to detect cosmic gamma-rays in the very-high-energy regime ($\sim$TeV). Recently these systems proved to be capable of measuring cosmic-ray chemical composition in the sub-PeV region by capturing direct Cherenkov photons emitted by charged primary particles. Extensive air sh…
The observation of the electromagnetic counterpart of gravitational-wave (GW) transient GW170817 demonstrated the potential in extracting astrophysical information from multimessenger discoveries. The forthcoming deployment of the first telescopes of the Cherenkov Telescope Array (CTA) observatory will coincide with Advanced LIGO/Virgo's next observing run, O3, enabling the monitoring of gamma-ray emission at E > 20 GeV, and thus particle acceleration, from GW sources. CTA will not be greatly limited by the precision of GW localization as it will be be capable of rapidly covering the GW error …
The Cherenkov Telescope Array (CTA) is planned to serve as a ground-based observatory for (very-)high-energy gamma-ray astronomy, open to a wide astrophysics community, providing a deep insight into the non-thermal high-energy universe. It foresees a factor of ~10 improvement in sensitivity above 100 GeV, with substantially better angular and spectral resolutions and wider field-of-view in comparison with currently operational experiments. The CTA consortium is investigating the different physics cases for different proposed array configurations and subsets. Pulsar Wind Nebulae (PWNe), the mos…
At the time large air Cherenkov arrays are being discussed for future gamma-ray observatories, we review the relationship between the targeted capabilities and the main design parameters taking into account construction costs. As an example application, we describe a telescope array optimized for observations between 1 TeV and a few 100 TeV and use detailed simulations to estimate its performances in comparison to science objectives.
The Gamma-ray Cherenkov Telescope (GCT) is one of the Small Size Telescopes (SSTs) proposed for the Cherenkov Telescope Array (CTA) aimed at the 1 TeV to 300 TeV energy range. GCT will be equipped with a Compact High-Energy Camera (CHEC) containing 2048 pixels of physical size about 6$\times$6~mm$^2$, leading to a field of view of over 8 degrees. Electronics based on custom TARGET ASICs and FPGAs sample incoming signals at a gigasample per second and provide a flexible triggering scheme. Waveforms for every pixel in every event are read out are on demand without loss at over 600 events per sec…
We present a method to reconstruct the longitudinal profile of electrons in showers using Cherenkov telescopes. We show how the Cherenkov light collected by an array of telescopes can be transformed into the number of electrons as a function of atmospheric depth. This method is validated using air shower and simplified telescope simulations. The reconstruction of the depth in which the shower has the maximum number of electrons ($\mathrm{X_{max}}$) opens the possibility of cosmic ray composition studies with Cherenkov telescopes in the energy range from 10 to 100 TeV. A resolution of less than…
The presence of muons in air-showers initiated by cosmic ray protons and nuclei is well established as a powerful tool to separate such showers from those initiated by gamma rays. However, so far this approach has been fully exploited only for ground level particle detecting arrays. We explore the feasibility of using Cherenkov light from muons as a background rejection tool for imaging atmospheric Cherenkov telescope arrays at the highest energies. We adopt an analytical model of the Cherenkov light from individual muons to allow rapid simulation of a large number of showers in a hybrid mode.…
The main interest of the present work is in analyzing the lateral distribution function (LDF) of Cherenkov radiation from particles that produced in Extensive Air Showers (EAS). The simulation of Cherenkov radiation LDF is fulfilled by utilizing the CORSIKA program at 1 PeV of the primary energy around the knee region for many primaries for vertical showers for Tunka-133 array conditions. Depending on the numerical simulation results of Cherenkov light LDF, sets of parameterized polynomial functions are resetted for several particles as a function of primary particle type. The comparison betwe…
Identification of Cherenkov light generated by muons has been suggested as a promising way to dramatically improve the background rejection power of Imaging Atmospheric Cherenkov Telescope (IACT) arrays at high energies. However, muon identification remains a challenging task, for which efficient algorithms are still being developed. We present an approach in which, rather than identifying Cherenkov light from muons, we simply consider the presence of Cherenkov light other than the main shower image in IACTs with large mirror area. We show that in the case of the H.E.S.S. array of five telesco…
The Cherenkov Telescope Array is the main global project of ground-based gamma-ray astronomy for the coming decades. Performance will be significantly improved relative to present instruments, allowing a new insight into the high-energy Universe [1]. The nominal CTA southern array will include a sub-array of seventy 4 m telescopes spread over a few square kilometers to study the sky at extremely high energies, with the opening of a new window in the multi-TeV energy range. The Gamma-ray Cherenkov Telescope (GCT) is one of the proposed telescope designs for that sub-array. The GCT prototype rec…
In this research, the simulation of lateral distribution function (LDF) of Cherenkov radiation was performed using CORSIKA software for two hadronic models QGSJET and GHEISHA. This simulation was performed for several elementary particles such as protons, iron nuclei, electrons and gamma quanta, in the range of energies 1-20 PeV for three zenith angles 0, 20 and 30 degrees. A parameterization of Cherenkov light LDF was performed for that simulated curves using Lorentzian function. The comparison between the obtained results for LDF of Cherenkov light with that measured with Yakutsk EAS array g…
A wide field-of-view Cherenkov telescope has been working in the surroundings of the Yakutsk array experiment since 2012. Its main function is to measure the waveform of the Cherenkov radiation signal induced by extensive air showers of cosmic rays. Analysis of the dataset collected by telescope is intended for the reconstruction of the parameters of the development of the shower in addition to the main shower characteristics measured by the rest of the array detectors. In this paper, the observed duration of the Cherenkov radiation signal as a function of the shower core distance is used to e…
The galactic and extragalactic surveys are two of the main proposed legacy projects of the Cherenkov Telescope Array (CTA), providing an unbiased view of the Universe at energies above tens of GeV. Considering Cherenkov telescopes' limited field of view ($<10^\circ$), the time needed for those projects is large. The many telescopes of CTA will allow taking full advantage of new pointing modes in which telescopes point slightly offset from one another. This divergent pointing mode leads to an increase of the array field of view ($\sim 14^\circ$ or larger) with competitive performance compared t…
The Cherenkov Telescope Array (CTA) is a planned gamma-ray observatory. CTA will incorporate about 100 imaging atmospheric Cherenkov telescopes (IACTs) at a Southern site, and about 20 in the North. Previous IACT experiments have used up to five telescopes. Subsequently, the design of a graphical user interface (GUI) for the operator of CTA involves new challenges. We present a GUI prototype, the concept for which is being developed in collaboration with experts from the field of Human-Computer Interaction. The prototype is based on Web technology; it incorporates a Python web server, Web Sock…
We consider a hybrid array composed of scintillation and water Cherenkov detectors designed to measure the cosmic ray primary mass composition at energies of about 1 EeV. We have developed a simulation and reconstruction chain to study the theoretical performance of such an array. In this work we investigate the sensitivity of mass composition observables in relation to the geometry of the array. The detectors are arranged in a triangular grid with fixed 750 m spacing and the configuration of the scintillator detectors is optimized for mass composition sensitivity. We show that the performance…
Enhancing Water Cherenkov Detector Arrays through multiPMT Modules
Università degli Studi di Napoli "Federico II"（那不勒斯费德里科二世大学）；Istituto Nazionale di Fisica Nucleare, Sezione di Napoli（意大利国家核物理研究所，那不勒斯分部）；Scuola Superiore Meridionale（南方高等学院）
The Cherenkov Telescope Array (CTA) is the next-generation gamma-ray observatory with sensitivity in the energy range from 20 GeV to beyond 300 TeV. CTA is proposed to consist of two arrays of 40-100 imaging atmospheric Cherenkov telescopes, with one site located in each of the Northern and Southern Hemispheres. The evaluation process for the candidate sites for CTA is supported by detailed Monte Carlo simulations, which take different attributes like site altitude and geomagnetic field configuration into account. In this contribution we present the comparison of the sensitivity and performanc…
We describe the design, performance, sensitivity and results of our recent experiments using the Australia Telescope Compact Array (ATCA) for lunar Cherenkov observations with a very wide (600 MHz) bandwidth and nanosecond timing, including a limit on an isotropic neutrino flux. We also make a first estimate of the effects of small-scale surface roughness on the effective experimental aperture, finding that contrary to expectations, such roughness will act to increase the detectability of near-surface events over the neutrino energy-range at which our experiment is most sensitive (though disto…
The Cherenkov Telescope Array (CTA) is the major ground-based gamma-ray observatory planned for the next decade and beyond. Consisting of two large atmospheric Cherenkov telescope arrays (one in the southern hemisphere and one in the northern hemisphere), CTA will have superior angular resolution, a much wider energy range, and approximately an order of magnitude improvement in sensitivity, as compared to existing instruments. The CTA science programme will be rich and diverse, covering cosmic particle acceleration, the astrophysics of extreme environments, and physics frontiers beyond the Sta…
The Cherenkov Telescope Array (CTA) is a major ground-based observatory proposed for gamma-ray astronomy. CTA is envisioned to consist of two large arrays of atmospheric Cherenkov telescopes for the study of sources of high-energy gamma rays in the energy range of a few tens of GeV to beyond 100 TeV. One array would be located in the southern hemisphere and one in the northern hemisphere. After a detailed search, we have identified two potential sites in the USA for the northern array. Both sites are located in northern Arizona. Here we describe the two sites and the deployment of instrumentat…
Cosmic electrons, positrons, protons, and antiprotons carry essential information about both astrophysical processes and fundamental physics. Charged particles provide signatures of dark matter annihilation or decay, \emph{in situ} in the universe, that are complementary to the other messengers of indirect dark matter detection, gamma rays and neutrinos. We discuss the science potential for measurements of charged particles by the Cherenkov Telescope Array (CTA), an instrument under development primarily for the study of cosmic gamma rays with energies $30\ \textrm{GeV} - 200\ \textrm{TeV}$.
The presence of muons in air-showers initiated by cosmic ray protons and nuclei is well established as a powerful tool to separate such showers from those initiated by gamma-rays. However, so far this approach has been fully exploited only for ground level particle detecting arrays. In this contribution, we explore the feasibility of using Cherenkov light from muons as a background rejection tool for imaging atmospheric Cherenkov telescope arrays at the highest energies. We adopt an analytical model of the Cherenkov light from individual muons to allow rapid simulation of a large number of sho…
A water Cherenkov detector array, LHAASO-WCDA, is proposed to be built at Shangri-la, Yunnan Province, China. As one of the major components of the LHAASO project, the main purpose of it is to survey the northern sky for gamma ray sources in the energy range from 100 GeV to 30 TeV. In order to design the water Cherenkov array efficiently to economize the budget, a Monte Carlo simulation is proceeded. With the help of the simulation, cost performance of different configurations of the array is obtained and compared with each other, serving as a guide for the more detailed design of the experime…
Cherenkov light lateral distribution function (CLLDF) in Extensive Air Showers (EAS) for different primary particles (e-, n , p, F, K and Fe) was simulated using CORSIKA code for conditions and configurations of Yakutsk EAS array with the fixed primary energy 3 PeV around the knee region at different zenith angles. Basing on the results of CLLDF numerical simulation, sets of approximated functions are reconstructed for different primary particles as a function of the zenith angle. A comparison of the parameterized CLLDF with that simulated with Yakutsk EAS array is verified. The parameterized …
An important aspect of the calibration of the Cherenkov Telescope Array is the pointing, which enables an exact alignment of each telescope and therefore allows to transform a position in the sky to a point in the plane of the Cherenkov camera and vice versa. The favoured approach for the pointing calibration of the medium size telescopes (MST) is the installation of an optical CCD-camera in the dish of the telescope that captures the position of the Cherenkov camera and of the stars in the night sky simultaneously during data taking. The adaption of this approach is presented in this proceedi…
The Cherenkov Telescope Array (CTA) is the next major ground-based observatory for gamma-ray astronomy. With CTA gamma-ray sources will be studied in the very-high energy gamma-ray range of a few tens of GeV to 100 TeV with up to ten times better sensitivity than available with current generation instruments. We discuss the proposed US contribution to CTA that comprises imaging atmospheric Cherenkov telescope with Schwarzschild-Couder (SC) optics. Key features of the SC telescope are a wide field of view of eight degrees, a finely pixelated camera with silicon photomultipliers as photon detect…
Measurements of cosmic ray electron+positron spectrum above 10 TeV with ground-based experiments is challenging because of the difficulty of rejection of hadronic extensive air shower background. We study the efficiency of rejection of the hadronic background with water Cherenkov detector array supplemented by muon detection layer. We show that addition of a continuous muon detection layer to the experimental setup allows to achieve a ~ 1e-5 rejection factor for hadronic background at 10 TeV and enables measurement of electron spectrum in 10-100 TeV energy range. We show that measurements of e…
In the framework of the Cherenkov Telescope Array (CTA), the GCT (Gamma-ray Cherenkov Telescope) team is building a dual-mirror telescope as one of the proposed prototypes for the CTA small size class of telescopes. The telescope is based on a Schwarzschild- Couder (SC) optical design, an innovative solution for ground-based Cherenkov astronomy, which allows a compact telescope structure, a lightweight large Field of View (FoV) camera and enables good angular resolution across the entire FoV. We review the different mechanical and optical components of the telescope. In order to characterise t…
We introduce a new simulation and analysis paradigm for Imaging Atmospheric Cherenkov Telescope (IACT) arrays, simulating the actual observation conditions as well as individual telescope configuration for each observation unit. Compared to existing frameworks, where simulations are usually generated using pre-defined settings, this run-wise simulation approach implies more realistic simulations and hence reduced systematic uncertainties. The computational effort of this dedicated simulation concept is notably independent of the amount of different observation configurations but just scales li…
On October $10^{\rm th}$ 2018 started the commissioning of the first Large Size Telescope (LST) prototype at the Cherenkov Telescope Array (CTA) northern site at the Observatorio del Roque de los Muchachos, Canary Island of La Palma (Spain). For a precise event energy reconstruction, an LST camera requires a uniform and constant calibration over a large dynamic range, up to $10^{4}$ photo-electrons (p.e.), for each camera photomultiplier tube (PMT). This paper describes the performance of the LST-1 camera calibration system (named CaliBox) in the first commissioning period and provides prelimi…
The next generation of Imaging Atmospheric Cherenkov telescope, like CTA, is going to strongly improve the detection capability of high-energy cosmic rays. In our paper we discuss the possibility to use such apparatus to detect Earth-skimming tau neutrinos. Interestingly the analysis shows that order few events per year can be detected for energies above $10^8$ GeV in the optimistic case of larger neutrino fluxes produced by Flat Spectrum Radio Quasars. However, even for more conservative cosmogenic neutrino fluxes such rate will be also obtained, but for a decade of running. This estimate see…
Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV to 10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as o…
The Cherenkov Telescope Array (CTA) is the observatory for ground-based gamma-ray astronomy that will shape the domain of TeV astronomy for the next decades. CTA will comprise more than 100 imaging air Cherenkov telescopes deployed on two sites, one in the northern hemisphere on La Palma and one in the southern hemisphere in Chile. A large fraction of CTA's observing time will be apportioned through a competitive proposal-driven time allocation scheme that is open to the scientific community. Hence CTA will become an astronomical tool that complements other large ground- and space-based observ…
The Cherenkov Telescope Array (CTA) is the next generation ground-based observatory for gamma-ray astronomy at very-high energies. It will be capable of detecting gamma rays in the energy range from 20 GeV to more than 300 TeV with unprecedented precision in energy and directional reconstruction. With more than 100 telescopes of three different types it will be located in the northern hemisphere at La Palma, Spain, and in the southern at Paranal, Chile. CTA will be one of the largest astronomical infrastructures in the world with open data access and it will address questions in astronomy, ast…
It is anticipated that forthcoming, next generation, atmospheric Cherenkov telescope arrays will include a number of medium-sized telescopes that are constructed using a dual-mirror Schwarzschild-Couder configuration. These telescopes will sample a wide ($8^{\circ}$) field of view using a densely pixelated camera comprising over $10^{4}$ individual readout channels. A readout frequency congruent with the expected single-telescope trigger rates would result in substantial data rates. To ameliorate these data rates, a novel, hardware-level Distributed Intelligent Array Trigger (DIAT) is envision…
Observations of dwarf galaxies and of the Milky Way halo with current ground-based Cherenkov telescopes have resulted in interesting limits on the cross-section for dark matter (DM) self- annihilation for WIMP masses above some 100 GeV. The future Cherenkov Telescope Array (CTA) is expected to further explore the parameter space of dark matter candidates that are predicted in extensions of the standard model of particle physics. Due to its low energy threshold (of order of few tens of GeV) and high sensitivity, CTA will also probe lower WIMP masses than current experiments, but the actual perf…
The Cherenkov Telescope Array (CTA) will be the next generation of ground based gamma-ray telescopes allowing us to study very high energy phenomena in the Universe. CTA aims to gain about a factor of ten in sensitivity compared to current experiments, extending the accessible gamma-ray energy range from a few tens of GeV to some hundreds of TeV. This increased gamma-ray source sensitivity, as well as the expected enhanced energy and spatial resolution, will allow exciting new insights in some key science topics. Additionally, CTA will provide a full sky-coverage by featuring the array located…
The last 20 years have seen the development of new techniques in Astroparticle Physics providing access to the highest end of the electromagnetic spectrum. It has been shown that some sources emit photons up to energies close to 100 TeV. Yet the fluxes of these photons are incredibly low and new detection techniques are needed to go higher in energy. A new technique that would use the new generation of Cherenkov Telescopes, i.e., the Cherenkov Telescope Array (CTA), is proposed to push further the energy frontier. It is based on the detection of the fluorescence radiation emitted in extensive …
Dwarf spheroidal galaxies are among the best environments that can be studied with Cherenkov telescopes for indirect searches of $γ$-ray signals coming from dark matter self-interaction (annihilation or decay), due to their proximity and negligible background emission. We present new determinations of the dark-matter amount - i.e. the astrophysical factors $J$ and $D$ - in dwarf-galaxy halos obtained through the MCMC Jeans analysis of their brightness and kinematic data. Such factors are of great importance to test the performances of the next-generation $γ$-ray instruments such as the Cherenk…
The Cherenkov Telescope Array (CTA) is the next generation observatory for very high energy gamma rays. The capability of the array to detect gamma-rays above 10 TeV is going to be achieved with a large number of Small Size Telescopes (SSTs) which will cover a large area. The subarray composed of SSTs has to compromise the number of telescopes (cost) and the large effective area. The separation between the telescopes has to be adjusted to achieve highest sensitivity with the smallest number of telescopes. On the other hand larger separation can worsen the energy threshold as well as the energy…
The Water Cherenkov Detector Array (WCDA) is a major component of the Large High Altitude Air Shower Array Observatory (LHAASO), a new generation cosmic-ray experiment with unprecedented sensitivity, currently under construction. The WCDA is aimed at the study of TeV $γ$-rays. In order to evaluate the prospects of searching for TeV $γ$-ray sources with the WCDA, we present in this paper a projection for the one-year sensitivity of the WCDA to TeV $γ$-ray sources from TeVCat (footnote: http://tevcat.uchicago.edu) using an all-sky approach. Out of 128 TeVCat sources observable to the WCDA up to …
