411 research outputs found
Verification of the optical system of the 9.7-m prototype Schwarzschild-Couder Telescope
No full textFor the first time in the history of ground-based x-ray astronomy, the on-axis performance of the dual mirror, aspheric, aplanatic Schwarzschild-Couder optical system has been demonstrated in a 9:7-m aperture imaging atmospheric Cherenkov telescope. The novel design of the prototype Schwarzschild-Couder Telescope (pSCT) is motivated by the need of the next-generation Cherenkov Telescope Array (CTA) observatory to have the ability to perform wide (≥8°) field-of-view observations simultaneously with superior imaging of atmospheric cascades (resolution of 0:067 per pixel or better). The pSCT design, if implemented in the CTA installation, has the potential to improve significantly both the x-ray angular resolution and the off-axis sensitivity of the observatory, reaching nearly the theoretical limit of the technique and thereby making a major impact on the CTA observatory sky survey programs, follow-up observations of multi-messenger transients with poorly known initial localization, as well as on the spatially resolved spectroscopic studies of extended x-ray sources. This contribution reports on the initial alignment procedures and point-spread-function results for the challenging segmented aspheric primary and secondary mirrors of the pSCT
Detection of the Crab Nebula with the 9.7 m prototype Schwarzschild-Couder telescope
No full textThe Schwarzschild-Couder Telescope (SCT) is a telescope concept proposed for the Cherenkov Telescope Array. It employs a dual-mirror optical design to remove comatic aberrations over an 8∘ field of view, and a high-density silicon photomultiplier camera (with a pixel resolution of 4 arcmin) to record Cherenkov emission from cosmic ray and gamma-ray initiated particle cascades in the atmosphere. The prototype SCT (pSCT), comprising a 9.7 m diameter primary mirror and a partially instrumented camera with 1536 pixels, has been constructed at the Fred Lawrence Whipple Observatory. The telescope was inaugurated in January 2019, with commissioning continuing throughout 2019. We describe the first campaign of observations with the pSCT, conducted in January and February of 2020, and demonstrate the detection of gamma-ray emission from the Crab Nebula with a statistical significance of 8.6σ
Detection of the Crab Nebula with the 9.7 m prototype Schwarzschild-Couder telescope
No full textInternational audienceThe Schwarzschild-Couder Telescope (SCT) is a telescope concept proposed for the Cherenkov Telescope Array. It employs a dual-mirror optical design to remove comatic aberrations over an 8∘ field of view, and a high-density silicon photomultiplier camera (with a pixel resolution of 4 arcmin) to record Cherenkov emission from cosmic ray and gamma-ray initiated particle cascades in the atmosphere. The prototype SCT (pSCT), comprising a 9.7 m diameter primary mirror and a partially instrumented camera with 1536 pixels, has been constructed at the Fred Lawrence Whipple Observatory. The telescope was inaugurated in January 2019, with commissioning continuing throughout 2019. We describe the first campaign of observations with the pSCT, conducted in January and February of 2020, and demonstrate the detection of gamma-ray emission from the Crab Nebula with a statistical significance of 8.6σ
Verification of the Optical System of the 9.7-m Prototype Schwarzschild-Couder Telescope
No full textInternational audienceFor the first time in the history of ground-based -ray astronomy, the on-axis performance of the dual mirror, aspheric, aplanatic Schwarzschild-Couder optical system has been demonstrated in a -m aperture imaging atmospheric Cherenkov telescope. The novel design of the prototype Schwarzschild-Couder Telescope (pSCT) is motivated by the need of the next-generation Cherenkov Telescope Array (CTA) observatory to have the ability to perform wide () field-of-view observations simultaneously with superior imaging of atmospheric cascades (resolution of per pixel or better). The pSCT design, if implemented in the CTA installation, has the potential to improve significantly both the -ray angular resolution and the off-axis sensitivity of the observatory, reaching nearly the theoretical limit of the technique and thereby making a major impact on the CTA observatory sky survey programs, follow-up observations of multi-messenger transients with poorly known initial localization, as well as on the spatially resolved spectroscopic studies of extended -ray sources. This contribution reports on the initial alignment procedures and point-spread-function results for the challenging segmented aspheric primary and secondary mirrors of the pSCT
Catalogue de cinquante tableaux peints par M. Alexandre Couder... / [expert] Febvre
No full text[Vente. Art. 1870-04-19. Paris][Collection. Art. Couder, Alexandre. 1870]Référence bibliographique : Lugt, 31939Appartient à l’ensemble documentaire : VenteEST2Avec mode text
Prototype Schwarzschild-Couder Telescope for the Cherenkov Telescope Array: Commissioning the Optical System
No full textA prototype Schwarzschild-Couder Telescope (pSCT) has been constructed at the Fred Lawrence Whipple Observatory as a candidate for the medium-sized telescopes of the Cherenkov Telescope Array Observatory (CTAO). CTAO is currently entering early construction phase of the project and once completed it will vastly improve very high energy gamma-ray detection component in multi-wavelength and multi-messenger observations due to significantly improved sensitivity, angular resolution and field of view comparing to the current generation of the ground-based gamma-ray observatories H.E.S.S., MAGIC and VERITAS. The pSCT uses a dual aspheric mirror design with a 9.7 m primary mirror and 5.4 m secondary mirror, both of which are segmented. The Schwarzschild-Couder (SC) optical system (OS) selected for the prototype telescope achieves wide field of view of 8 degrees and simultaneously reduces the focal plane plate scale allowing an unprecedented compact (0.78m diameter) implementation of the high-resolution camera (6mm/ 0.067deg per imaging pixel with 11,328 pixels) based on the silicon photo-multipliers (SiPMs). The OS of the telescope is designed to eliminate spherical and comatic aberrations and minimize astigmatism to radically improve off-axis imaging and consequently angular resolution across all the field of view with respect to the conventional single-mirror telescopes. Fast and high imaging resolution OS of the pSCT comes with the challenging submillimeter-precision custom alignment system, which was successfully demonstrated with an on-axis point spread function (PSF) of 2.9 arcmin prior to the first-light detection of the Crab Nebula in 2020. Ongoing commissioning activities aim to meet the on-axis PSF design goal of 2.6 arcmin, verify the off-axis performance of the pSCT OS, and develop techniques to maintain alignment stability over telescope structural deformations from pointing and temperature variations. In this contribution, we report on the commissioning status, the optical alignment procedures adopted for segmented OS, and alignment progress to verify and validate design requirements
Prototype 9.7 m Schwarzschild-Couder telescope for the Cherenkov Telescope Array: status of the optical system
No full textThe Cherenkov Telescope Array (CTA) is an international project for a next-generation ground-based gamma ray observatory, aiming to improve on the sensitivity of current-generation experiments by an order of magnitude and provide energy coverage from 30 GeV to more than 300 TeV. The 9.7m Schwarzschild-Couder (SC) candidate medium-size telescope for CTA exploits a novel aplanatic two-mirror optical design that provides a large field of view of 8 degrees and substantially improves the off-axis performance giving better angular resolution across all of the field of view with respect to single-mirror telescopes. The realization of the SC optical design implies the challenging production of large aspherical mirrors accompanied by a submillimeter-precision custom alignment system. In this contribution we report on the status of the implementation of the optical system on a prototype 9.7 m SC telescope located at the Fred Lawrence Whipple Observatory in southern Arizona
Faust Et Marguerite : Drame Fantastique En 3 Actes Et 4 Tableux ; Représenté, Pour La Première Fois, A Paris, Sur Le Théatre Du Gymnase-Dramatique, Le 19 Aout 1850 / Par M. Michel Carré. Décors de MM. Devoir et Bolard. Musique de M. Couder
No full textFAUST ET MARGUERITE : DRAME FANTASTIQUE EN 3 ACTES ET 4 TABLEUX ; REPRÉSENTÉ, POUR LA PREMIÈRE FOIS, A PARIS, SUR LE THÉATRE DU GYMNASE-DRAMATIQUE, LE 19 AOUT 1850 / PAR M. MICHEL CARRÉ. DÉCORS DE MM. DEVOIR ET BOLARD. MUSIQUE DE M. COUDER
Faust Et Marguerite : Drame Fantastique En 3 Actes Et 4 Tableux ; Représenté, Pour La Première Fois, A Paris, Sur Le Théatre Du Gymnase-Dramatique, Le 19 Aout 1850 / Par M. Michel Carré. Décors de MM. Devoir et Bolard. Musique de M. Couder (1)
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Titelseite (4)
Acte I. Tableau I. (5)
Acte I. Tableau II. (9)
Acte II. Scene I. - XV. (16)
Acte III. Scene I. - X. (28
Construction of a Schwarzschild-Couder telescope as a candidate for the Cherenkov Telescope Array: status of the optical system
No full textWe present the design and the status of procurement of the optical system of the prototype Schwarzschild-Couder telescope (pSCT), for which construction is scheduled to begin in fall at the Fred Lawrence Whipple Observatory in southern Arizona, USA. The Schwarzschild-Couder telescope is a candidate for the medium-sized telescopes of the Cherenkov Telescope Array, which utilizes imaging atmospheric Cherenkov techniques to observe gamma rays in the energy range of 60Gev-60TeV. The pSCT novel aplanatic optical system is made of two segmented aspheric mirrors. The primary mirror has 48 mirror panels with an aperture of 9.6 m, while the secondary, made of 24 panels, has an diameter of 5.4 m. The resulting point spread function (PSF) is required to be better than 4 arcmin within a field of view of 6.4 degrees (80% of the field of view), which corresponds to a physical size of 6.4 mm on the focal plane. This goal represents a challenge for the inexpensive fabrication of aspheric mirror panels and for the precise alignment of the optical system as well as for the rigidity of the optical support structure. In this submission we introduce the design of the Schwarzschild-Couder optical system and describe the solutions adopted for the manufacturing of the mirror panels and their integration with the optical support structure
Design and performance of the prototype Schwarzschild-Couder Telescope camera
No full textThe Cherenkov Telescope Array (CTA) is the next-generation ground-based
observatory for very-high-energy gamma-ray astronomy. An innovative 9.7 m
aperture, dual-mirror Schwarzschild-Couder Telescope (SCT) design is a
candidate design for CTA Medium-Sized Telescopes. A prototype SCT (pSCT) has
been constructed at the Fred Lawrence Whipple Observatory in Arizona, USA. Its
camera is currently partially instrumented with 1600 pixels covering a field of
view of 2.7 degrees square. The small plate scale of the optical system allows
densely packed silicon photomultipliers to be used, which combined with
high-density trigger and waveform readout electronics enable the
high-resolution camera. The camera's electronics are capable of imaging air
shower development at a rate of one billion samples per second. We describe the
commissioning and performance of the pSCT camera, including trigger and
waveform readout performance, calibration, and absolute GPS time stamping. We
also present the upgrade to the camera, which is currently underway. The
upgrade will fully populate the focal plane, increasing the field of view to 8
degree diameter, and lower the front-end electronics noise, enabling a lower
trigger threshold and improved reconstruction and background rejection
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