The Schwarzschild–Couder Telescope (SCT) is a dual mirror medium-sized telescope proposed for the Cherenkov Telescope Array (CTA), the next-generation very-high energy (from about 20 GeV to 300 TeV) ...gamma-ray observatory. The SCT design consists of a dual-mirror optics and a high resolution camera with a field of view (FoV) of 8 degrees squared, which will allow exceptional performance in terms of angular resolution and background rejection. A prototype telescope (named pSCT) has been installed at the Fred Lawrence Whipple Observatory in Arizona, USA. Its camera is partially equipped and covers a FoV of 2.7°. The pSCT has recently successfully detected the Crab Nebula with a statistical significance of 8.6 standard deviations. The upgrade of the pSCT focal plane is now ongoing, aimed to equip the full camera with upgraded sensors and electronics, enhancing the telescope field of view from the current 2.7°to the final 8°. In this presentation, an overview of the pSCT project and obtained results will be given, together with the camera upgrade status and expected performance.
According to radiative models, radio galaxies are predicted to produce γ‐rays from the earliest stages of their evolution onwards. The study of the high‐energy emission from young radio sources is ...crucial for providing information on the most energetic processes associated with these sources, the actual region responsible for this emission, as well as the structure of the newly born radio jets. Despite systematic searches for young radio sources at γ‐ray energies, only a handful of detections have been reported so far. Taking advantage of more than 11 years of Fermi‐large area telescope (LAT) data, we investigate the γ‐ray emission of 162 young radio sources (103 galaxies and 59 quasars), the largest sample of young radio sources used so far for a γ‐ray study. We analyzed the Fermi‐LAT data of each source separately to search for a significant detection. In addition, we performed the first stacking analysis of this class of sources in order to investigate the γ‐ray emission of the young radio sources that are undetected at high energies. In this note, we present the results of our study and we discuss their implications for the predictions of γ‐ray emission from this class of sources.
Ice formation is a serious issue in many fields, from energy to aerospace, compromising the devices’ efficiency and security. Superhydrophobicity has been demonstrated to be correlated to the ...anti-icing properties of surfaces. However, fabricating surfaces with robust water repellence properties also at subzero temperature is still a great challenge. In this work, femtosecond laser (fs-laser) texturing is exploited to produce superhydrophobic surfaces with anti-icing properties on Al2024, an aluminum alloy of great interest in cold environments, in particular for aircraft production. Our textured substrates present self-cleaning properties and robust water repellency at subzero temperatures. Moreover, outstanding anti-icing properties are achieved on the textured surfaces at −20 °C, with water droplets bouncing off the surface before freezing.
The ctools open-source software package was developed for the scientific analysis of astronomical data from Imaging Air Cherenkov Telescopes (IACTs), such as H.E.S.S., VERITAS, MAGIC, and the future ...Cherenkov Telescope Array (CTA). To date, the software has been mainly tested using simulated CTA data; however, upon the public release of a small set of H.E.S.S. observations of the Crab nebula, MSH 15–52, RX J1713.7–3946, and PKS 2155–304 validation using real data is now possible. We analysed the data of the H.E.S.S. public data release using ctools version 1.6 and compared our results to those published by the H.E.S.S. Collaboration for the respective sources. We developed a parametric background model that satisfactorily describes the expected background rate as a function of reconstructed energy and direction for each observation. We used that model, and tested all analysis methods that are supported by ctools, including novel unbinned and joint or stacked binned analyses of the measured event energies and reconstructed directions, and classical On-Off analysis methods that are comparable to those used by the H.E.S.S. Collaboration. For all analysis methods, we found a good agreement between the ctools results and the H.E.S.S. Collaboration publications considering that they are not always directly comparable due to differences in the datatsets and event processing software. We also performed a joint analysis of H.E.S.S. and Fermi-LAT data of the Crab nebula, illustrating the multi-wavelength capacity of ctools. The joint Crab nebula spectrum is compatible with published literature values within the systematic uncertainties. We conclude that the ctools software is mature for the analysis of data from existing IACTs, as well as from the upcoming CTA.
We present the characterization of the new Frontend Electronics (FEE) developed for the Schwarzschild-Couder Telescope (SCT) camera of the CTA experiment. The new FEE is based on a new ...Application-Specific Integrated Circuit (ASIC) intended to read-out arrays of Silicon Photomultipliers (SiPMs) for low-level light detection down to the single photoelectron, called SMART (SiPM Multichannel ASIC for high Resolution Cherenkov Telescopes). The analog channel is composed of a high speed path with programmable gain and pole-zero filter designed for photon-counting. An external fast digitizer can be used for the photon-counting analysis. A slow path allows the measurement of the mean SiPM current, sampled by an internal 10-bit ADC. We present the characterization results obtained when coupling the SMART to a 16 SiPM matrix produced by Fondazione Bruno Kessler (FBK). Results in terms of charge spectrum, signal-to-noise ratio and dynamic range will be presented. The SMART ASIC was then coupled to the SCT readout electronics based on the TARGET ASICs, able to digitize waveforms at a frequency of 1GS/s and to generate trigger signals. In this work, we further present the preliminary characterization obtained on the full FEE chain.
Fast radio bursts (FRBs) are one of the most exciting new mysteries of astrophysics. Their origin is still unknown, but recent observations seem to link them to soft gamma repeaters and, in ...particular, to magnetar giant flares (MGFs). The recent detection of a MGF at GeV energies by the Fermi Large Area Telescope (LAT) motivated the search for GeV counterparts to the >100 currently known FRBs. To date, none of these has a known gamma-ray counterpart. Taking advantage of more than 12 years of Fermi-LAT data, we perform a search for gamma-ray emission from almost all the reported repeating and non-repeating FRBs. We analyze on different time scales the Fermi-LAT data for each individual source separately and perform a cumulative analysis on the repeating ones. In addition, we perform the first stacking analysis at GeV energies of this class of sources in order to constrain the gamma-ray properties of the FRBs. The stacking analysis is a powerful method that allows for a possible detection from below-threshold FRBs providing important information on these objects. In this proceeding we present preliminary results of our study and we discuss their implications for the predictions of gamma-ray emission from this class of sources.
Fast radio bursts (FRBs) are one of the most exciting new mysteries of astrophysics. Their origin is still unknown, but recent observations seems to link them to Soft Gamma Repeaters and, in ...particular, to magnetar giant flares (MGFs). The recent detection of a MGF at GeV energies by the \textit{Fermi} Large Area Telescope (LAT) motivated the search for GeV counterparts to the >100 currently known FRBs. Taking advantage of more than 12 years of \textit{Fermi}-LAT data, we perform a search for gamma-ray emission from all the reported repeating and non-repeating FRBs. We analyse on different-time scales the \textit{Fermi}-LAT data of each individual source separately, including a cumulative analysis on the repeating ones. In addition, we perform the first stacking analysis at GeV energies of this class of sources in order to constrain the gamma-ray properties of the FRBs that are undetected at high energies. The stacking analysis is a powerful method that allow a possible detection from below-threshold FRBs providing important information on these objects. In this talk we present the preliminary results of our study and we discuss their implications for the predictions of gamma-ray emission from this class of sources
According to radiative models, radio galaxies and quasars are predicted to produce gamma rays from the earliest stages of their evolution. Exploring their high-energy emission is crucial for ...providing information on the most energetic processes, the origin and the structure of the newly born radio jets. Taking advantage of more than 11 years of \textit{Fermi}-LAT data, we investigate the gamma-ray emission of 162 young radio sources (103 galaxies and 59 quasars), the largest sample of young radio sources used so far for such a gamma-ray study. We separately analyze each source and perform the first stacking analysis of this class of sources to investigate the gamma-ray emission of the undetected sources. We detect significant gamma-ray emission from 11 young radio sources, four galaxies and seven quasars, including the discovery of significant gamma-ray emission from the compact radio galaxy PKS 1007+142 (z=0.213). The cumulative signal of below-threshold young radio sources is not significantly detected. However, it is about one order of magnitude below than those derived from the individual sources, providing stringent upper limits on the gamma-ray emission from young radio galaxies (\(F_{\gamma}< 4.6 \times 10^{-11}\) ph cm\(^{-2}\) s\(^{-1}\)) and quasars (\(F_{\gamma}< 10.1 \times 10^{-11}\) ph cm\(^{-2}\) s\(^{-1}\)), and enabling a comparison with the models proposed. With this analysis of more than a decade of \textit{Fermi}-LAT observations, we can conclude that while individual young radio sources can be bright gamma-ray emitters, the collective gamma-ray emission of this class of sources is not bright enough to be detected by \textit{Fermi}-LAT.
According to radiative models, radio galaxies are predicted to produce gamma-rays from the earliest stages of their evolution onwards. The study of the high-energy emission from young radio sources ...is crucial for providing information on the most energetic processes associated with these sources, the actual region responsible for this emission, as well as the structure of the newly born radio jets. Despite systematic searches for young radio sources at gamma-ray energies, only a handful of detections have been reported so far. Taking advantage of more than 11 years of Fermi-LAT data, we investigate the gamma-ray emission of 162 young radio sources (103 galaxies and 59 quasars), the largest sample of young radio sources used so far for a gamma-ray study. We analysed the Fermi-LAT data of each source separately to search for a significant detection. In addition, we performed the first stacking analysis of this class of sources in order to investigate the gamma-ray emission of the young radio sources that are undetected at high energies. In this note we present the results of our study and we discuss their implications for the predictions of gamma-ray emission from this class of sources.
According to radiative models, radio galaxies are predicted to produce gamma rays from the earliest stages of their evolution onwards.The study of the high-energy emission from young radio sources is ...crucial for providing information on the most energetic processes associated with these sources, the actual region responsible for this emission, as well as the structure of the newly born radio jets. Despite systematic searches for young radio sources at gamma-ray energies, only a handful of detections have been reported so far. Taking advantage of more than 11 years of \textit{Fermi}-LAT data, we investigate the gamma-ray emission of 162 young radio sources (103 galaxies and 59 quasars), the largest sample of young radio sources used so far for a gamma-ray study. We analyse the \textit{Fermi}-LAT data of each individual source separately to search for a significant detection. In addition, we perform the first stacking analysis of this class of sources in order to investigate the gamma-ray emission of the young radio sources that are undetected at high energies. We report the detection of significant gamma-ray emission from 11 young radio sources, including the discovery of significant gamma-ray emission from the compact radio galaxy PKS 1007+142. Although the stacking analysis of below-threshold young radio sources does not result in a significant detection, it provides stringent upper limits to constrain the gamma-ray emission from these objects. In this talk we present the results of our study and we discuss their implications for the predictions of gamma-ray emission from this class of sources.
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