相关论文: VERITAS Distant Laser Calibration and Atmospheric …
A technique for detecting the presence of cloud in the field of view of an atmospheric Cerenkov telescope using a far infra red radiometer is described. Models for the radiative emission from clear and cloudy skies are tested and found to…
We have performed a measurement of the absolute yield of fluorescence photons at the Fermilab Test Beam. A systematic uncertainty at 5% level was achieved by the use of Cherenkov radiation as a reference calibration light source. A…
A laser diffraction experiment was conducted to study light propagation in air. The experiment is easy to reproduce and it is based on simple optical principles. Two optical sensors (segmented photo-diodes) are used for measuring the…
VERITAS is a state-of-the-art ground-based gamma-ray observatory that operates in the very high-energy (VHE) region of 100 GeV to 50 TeV. The observatory consists of an array of four 12m-diameter imaging atmospheric Cherenkov telescopes…
The VERITAS Imaging Atmospheric Cherenkov Telescope array (IACT) was augmented in 2019 with high-speed focal plane electronics to create a new Stellar Intensity Interferometry (SII) observational capability (VERITAS-SII, or VSII). VSII…
Imaging atmospheric Cherenkov telescopes (IACTs) are sensitive to rare gamma-ray photons, buried in the background of charged cosmic-ray (CR) particles, the flux of which is several orders of magnitude greater. The ability to separate gamma…
Imaging surveys of galaxies will have a high number density and angular resolution yet a poor redshift precision. Intensity maps of neutral hydrogen (HI) will have accurate redshift resolution yet will not resolve individual sources. Using…
VERITAS is an array of four imaging atmospheric Cherenkov telescopes that observes gamma-ray sources in the very high energy range (VHE, E>100 GeV). A large fraction of the known gamma-ray sources are of extragalactic origin and belong to…
Imaging atmospheric Cherenkov telescope (IACT) arrays such as VERITAS are used for ground-based very high-energy gamma-ray astronomy. This is accomplished by the detection and analysis of the Cherenkov light produced by gamma-ray-initiated…
Arrays of imaging atmospheric Cherenkov telescopes (IACT) are superb instruments to probe the very-high-energy gamma-ray sky. This type of telescope focuses the Cherenkov light emitted from air showers, initiated by very-high-energy gamma…
Major uncertainties in the fluorescence energy measurement come from the precision of various atmospheric transmission, air Cerenkov subtraction, light multiple-scattering and cloud corrections. The Auger program for atmospheric monitoring,…
This paper discusses the multi-wavelength scanning Raman lidar being built at Lidar Division, CEILAP (CITEDEF-CONICET) in the frame of the Argentinean Cherenkov Telescope Array (CTA) collaboration to measure the spectral characteristics of…
The physics of the non-thermal Universe provides information on the acceleration mechanisms in extreme environments, such as black holes and relativistic jets, neutron stars, supernovae or clusters of galaxies. In the presence of magnetic…
Molecular clouds act as primary targets for cosmic-ray interactions and are expected to shine in gamma-rays as a by-product of these interactions. Indeed several detected gamma-ray sources both in HE and VHE gamma-rays (HE: 100 MeV < E <…
We present a new approach to the pointing determination of Imaging Atmospheric Cherenkov Telescopes (IACTs). This method is universal and can be applied to any IACT with minor modifications. It uses the trajectories of the stars in the…
A high-precision calibration method for all-sky cameras has been realized using images from the Ali observatory in Tibet, providing application results for atmospheric extinction, night sky brightness, and known variable stars. This method…
The detailed simulation of extended air showers (EAS) and their emission of Cherenkov and fluorescence light requires increasing computation time and storage volume with increasing energy of the primary particle. Given these limitations, it…
Extensive air showers created by high-energy particles interacting with the Earth atmosphere can be detected using imaging atmospheric Cherenkov telescopes (IACTs). The IACT images can be analyzed to distinguish between the events caused by…
Most neighboring stars are still detected as point sources and are beyond the angular resolution reach of current observatories. Methods to improve our understanding of stars at high angular resolution are investigated. Air Cherenkov…
Laser communication has advances in compared with radio frequency communication as result of much high carrier frequency from ultraviolet to near infrared. Very narrow laser beam is possible to form with very high power density. But laser…