arXiv subjects

Luca Riitano

Publications and source records attributed to Luca Riitano.

3 recordsLinked to original sources

arXiv2025

Design and Performance of the Upgraded Prototype Schwarzschild-Couder Telescope Camera Module

The Cherenkov Telescope Array Observatory (CTAO) is a ground-based observatory that will improve upon the sensitivities of the current generation of very-high-energy gamma-ray instruments. The Schwarzschild-Couder Telescope (SCT) is a dual-mirror candidate design for a CTAO Medium-Sized Telescope (MST). The prototype Schwarzschild-Couder Telescope (pSCT) was inaugurated in 2019 at Fred Lawrence Whipple Observatory (FLWO) in Arizona and observed significant gamma-ray emission from the Crab Nebula with a partially populated camera. The pSCT camera is currently being upgraded to fully instrument the focal plane with 11,328 silicon photomultiplier (SiPM) pixels split between 177 camera modules. Additionally, the modules will feature upgraded electronics designed to reduce electronics crosstalk and noise. A module calibration procedure has been developed using a preproduction test module. Following this calibration procedure, performance testing shows that the upgrade module has low noise, minimal electronics crosstalk, and excellent charge resolution. After calibration and optimization, the 177 production modules will be installed in the pSCT camera for commissioning. This will be followed by observations of known VHE gamma-ray sources for camera performance validation.

astro-ph.IM↗

arXiv2025

The Schwarzschild-Couder Telescope for the Cherenkov Telescope Array Observatory

The Cherenkov Telescope Array Observatory (CTAO) will greatly improve upon sensitivities in the field of very-high-energy gamma-ray astrophysics. The CTAO northern site (CTAO-North, La Palma, Spain) currently hosts LST-1 with the remaining three large-sized telescopes (LSTs) expected in mid-2026 and one medium-sized telescope (MST) expected in mid-2027. The CTAO southern site (CTAO-South, Paranal, Chile) expects the delivery of five small-sized telescopes (SSTs) and two MSTs in early 2026 with on-site construction beginning in mid-2026. The dual-mirrored Schwarzschild-Couder Telescope (SCT) is a candidate MST for CTAO-South and is capable of observations in the energy range of 100 GeV to 10 TeV, the core of CTAO's 20 GeV to 300 TeV energy range. Inaugurated in January 2019, the prototype SCT (pSCT) located at the Fred Lawrence Whipple Observatory in southern Arizona observed gamma-ray emission from the Crab Nebula at a significance of 8.6 sigma in 2020. The pSCT utilizes a novel dual-mirror optics design and a densely packed focal plane of silicon photomultipliers (SiPMs). An upgrade of the pSCT camera is underway to fully instrument the camera with 11,328 pixels and an 8-degree diameter FoV. In addition, upgraded electronics will lower the front-end electronics noise, allowing for a lower trigger threshold and improved event reconstruction and background rejection. This work will present the status of the upgrade of the pSCT and discuss the future of the SCT.

astro-ph.IM↗

arXiv2022

Design and Performance of the Prototype Schwarzschild-Couder Telescope Camera

The prototype Schwarzschild-Couder Telescope (pSCT) is a candidate for a medium-sized telescope in the Cherenkov Telescope Array. The pSCT is based on a novel dual mirror optics design which reduces the plate scale and allows for the use of silicon photomultipliers as photodetectors. The prototype pSCT camera currently has only the central sector instrumented with 25 camera modules (1600 pixels), providing a 2.68$^{\circ}$ field of view (FoV). The camera electronics are based on custom TARGET (TeV array readout with GSa/s sampling and event trigger) application specific integrated circuits. Field programmable gate arrays sample incoming signals at a gigasample per second. A single backplane provides camera-wide triggers. An upgrade of the pSCT camera is in progress, which will fully populate the focal plane. This will increase the number of pixels to 11,328, the number of backplanes to 9, and the FoV to 8.04$^{\circ}$. Here we give a detailed description of the pSCT camera, including the basic concept, mechanical design, detectors, electronics, current status and first light.

astro-ph.IM↗