Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userCommissioning and initial performance of the H.E.S.S. II drive system
143
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The H.E.S.S. observatory was recently extended with a fifth telescope located at the center of the array - H.E.S.S. II. With a reflector roughly six times the area of the smaller telescopes and four times more pixels per sky area, this new telescope can resolve images of particle showers in the atmosphere in unprecedented detail and explore the gamma-ray sky in the poorly studied regime around a few tens of Giga electron-volt. H.E.S.S. II has been equipped with a high-performance drive system that can deliver the high torque necessary to accelerate and slew the 600 tonnes telescope while keeping a good tracking accuracy. A modular design with a high degree of redundancy has been employed to achieve stability of operation and to ensure that the telescope can be moved to a safe position within a short period of time. Each axis is driven by four 28 kW servo motors which are pair-wise torque-biased and synchronized through a state of the art Programmable Logic Controller (PLC). With this system, a fast repositioning and a minimal settling time has been achieved - crucial when studying transient sources such as gamma-ray bursts which are a prime target for this telescope. This contribution will report on the successful commissioning of the H.E.S.S. II drive system in the first half of 2012 at the H.E.S.S. site in Namibia. The technical implementation and the performance of the drive system will be presented.
rate research
Read More
The Gemini Multi-conjugate Adaptive Optics System - GeMS, a facility instrument mounted on the Gemini South telescope, delivers a uniform, near diffraction limited images at near infrared wavelengths (0.95 microns- 2.5 microns) over a field of view of 120 arc seconds. GeMS is the first sodium layer based multi laser guide star adaptive optics system used in astronomy. It uses five laser guide stars distributed on a 60 arc seconds square constellation to measure for atmospheric distortions and two deformable mirrors to compensate for it. In this paper, the second devoted to describe the GeMS project, we present the commissioning, overall performance and operational scheme of GeMS. Performance of each sub-system is derived from the commissioning results. The typical image quality, expressed in full with half maximum, Strehl ratios and variations over the field delivered by the system are then described. A discussion of the main contributor to performance limitation is carried-out. Finally, overheads and future system upgrades are described.
The Imaging Atmospheric Cherenkov Telescope (IACT) works by imaging the very short flash of Cherenkov radiation generated by the cascade of relativistic charged particles produced when a TeV gamma ray strikes the atmosphere. This energetic air shower is initiated at an altitude of 10-30 km depending on the energy and the arrival direction of the primary gamma ray. Whether the best image of the shower is obtained by focusing the telescope at infinity and measuring the Cherenkov photon angles or focusing on the central region of the shower is a not obvious question. This is particularly true for large size IACT for which the depth of the field is much smaller. We address this issue in particular with the fifth telescope (CT5) of the High Energy Stereoscopic System (H.E.S.S.); a 28 m dish large size telescope recently entered in operation and sensitive to an energy threshold of tens of GeVs. CT5 is equipped with a focus system, its working principle and the expected effect of focusing depth on the telescope sensitivity at low energies (50-200 GeV) is discussed.
The 14 years old cameras of the H.E.S.S. 12-m telescopes have been upgraded in 2015/2016, with the goals of reducing the system failure rate, reducing the dead time and improving the overall performance of the array. This conference contribution describes the various tests that were carried out on the cameras and their sub-components both in the lab and on site. It also gives an overview of the commissioning and calibration procedures adopted during and after the installation, including e.g. flat-fielding and trigger threshold scans. Finally, it reports in detail about the overall performance of the four new H.E.S.S. I cameras, using very recent data.
The ATLAS trigger has been used very successfully to collect collision data during 2009 and 2010 LHC running at centre of mass energies of 900 GeV, 2.36 TeV, and 7 TeV. This paper presents the ongoing work to commission the ATLAS trigger with proton collisions, including an overview of the performance of the trigger based on extensive online running. We describe how the trigger has evolved with increasing LHC luminosity and give a brief overview of plans for forthcoming LHC running.
The Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) is a high contrast integral field spectrograph (IFS) whose design was driven by WFIRST coronagraph instrument requirements. We present commissioning and operational results using PISCES as a camera on the High Contrast Imaging Testbed at JPL. PISCES has demonstrated ability to achieve high contrast spectral retrieval with flight-like data reduction and analysis techniques.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
