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arXiv · 2109.06225

Detection of the Crab Nebula by the prototype Schwarzschild-Couder Telescope

Abstract

The Schwarzschild-Couder Telescope (SCT) is a medium-sized telescope technology proposed for the Cherenkov Telescope Array. It uses a novel dual-mirror optical design that removes comatic aberrations across its entire field of view. The SCT camera employs high-resolution silicon photomultiplier (SiPM) sensors with a pixel size of 4 arcminutes. A prototype SCT (pSCT) has been constructed at the Fred Lawrence Whipple Observatory in Arizona, USA. An observing campaign in 2020, with a partial camera of 1600 pixels (2.7 degrees by 2.7 degrees field of view) resulted in detection of the Crab Nebula at 8.6 sigma statistical significance. Work on the pSCT camera and optical system is ongoing to improve performance and prepare for an upcoming camera upgrade. The pSCT camera upgrade will replace the current camera modules with improved SiPMs and readout electronics and will expand the camera to its full design field of view of 8 degrees in diameter (11,328 pixels). The fully upgraded pSCT will enable next-generation very-high-energy gamma-ray astrophysics through excellent background rejection and angular resolution. In this presentation we describe first results from the successful operation of the pSCT and future plans.

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C. B. Adams, G. Ambrosi, M. Ambrosio, C. Aramo, P. I. Batista, W. Benbow, B. Bertucci, E. Bissaldi, M. Bitossi, A. Boiano, C. Bonavolontà, R. Bose, A. Brill, A. M. Brown, J. H. Buckley, R. A. Cameron, R. Canestrari, M. Capasso, M. Caprai, C. E. Covault, D. Depaoli, L. Di Venere, M. Errando, S. Fegan, Q. Feng, E. Fiandrini, A. Furniss, A. Gent, N. Giglietto, F. Giordano, E. Giro, R. Halliday, O. Hervet, J. Holder, T. B. Humensky, S. Incardona, M. Ionica, W. Jin, D. Kieda, F. Licciulli, S. Loporchio, G. Marsella, V. Masone, K. Meagher, T. Meures, B. A. W. Mode, S. A. I. Mognet, R. Mukherjee, A. Okumura, N. Otte, F. R. Pantaleo, R. Paoletti, G. Pareschi, F. Di Pierro, E. Pueschel, D. Ribeiro, L. Riitano, E. Roache, J. Rousselle, A. Rugliancich, M. Santander, R. Shang, L. Stiaccini, H. Tajima, L. P. Taylor, L. Tosti, G. Tovmassian, G. Tripodo, V. Vagelli, M. Valentino, J. Vandenbroucke, V. V. Vassiliev, D. A. Williams, A. Zink. 2021-09-13. Detection of the Crab Nebula by the prototype Schwarzschild-Couder Telescope. https://doi.org/10.22323/1.395.0830

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