Related papers: Determining Atmospheric Aerosol Content With An In…
Reconstruction of energies of very-high-energy gamma-rays observed by imaging atmospheric Cherenkov telescopes is affected by changes in the atmospheric conditions and the performance of telescope components. Reliable calibration schemes…
The Imaging Atmospheric Cherenkov technique allows to detect very high energy gamma rays from few tens of GeV to hundreds of TeV using ground-based instrumentation. At these energies a gamma ray generates a shower of secondary particles…
Air fluorescence measurements of cosmic ray energy must be corrected for attenuation of the atmosphere. In this paper we show that the air-showers themselves can yield a measurement of the aerosol attenuation in terms of optical depth,…
Telescopes, designed with semi-conductor based photo sensors, have the potential to detect Cherenkov or fluorescence light emitted by cosmic-rays in the atmosphere. Such telescopes promise a high duty cycle and efficiency in remote harsh…
A small contribution of molecular Bremsstrahlung radiation to the air-fluorescence yield in the UV range is estimated based on an approach previously developed in the framework of the radio-detection of showers in the gigahertz frequency…
The air fluorescence technique is used to detect ultra-high energy cosmic rays (UHECR), and to estimate their energy. Of fundamental importance is the photon yield due to excitation by electrons, in air of various densities and…
Polarization measurements of the twilight background with Wide-Angle Polarization Camera (WAPC) are used to detect the depolarization effect caused by stratospheric aerosol near the altitude of 20 km. Based on a number of observations in…
The paper contains the review of a number of wide-angle polarization CCD-measurements of the twilight sky in V and R color bands with effective wavelengths equal to 550 and 700 nm. The basic factors effecting (usually decreasing) on the…
Imaging atmospheric Cherenkov telescopes (IACTs) detect gamma rays by measuring the Cherenkov light emitted by secondary particles in the air shower when the gamma rays hit the atmosphere. At low energies, the limited amount of Cherenkov…
A significant source of noise for Imaging Atmospheric Cherenkov Telescopes (IACTs), which are designed to measure air showers caused by astrophysical gamma rays, is optical light emitted from the night sky. This Night Sky Background (NSB)…
The reconstruction of the energy and the depth of maximum $X_{\rm max}$ of an extensive air shower depends on the multiple scattering of fluorescence photons in the atmosphere. In this work, we explain how atmospheric aerosols, and…
This paper considers environmental problems of natural and anthropogenic atmospheric aerosol pollution and its global and regional monitoring. Efficient aerosol investigations may be achieved by spectropolarimetric measurements.…
Long-term series of measurement of spectral transparency of the atmosphere (\lambda = 430 nm) and atmospheric optical thickness (AOT) measured by multimode photometer CE 318 in the region of Yakutsk array are analyzed. Correlation of AOT…
Measurements are reported on the fluorescence of air as a function of depth in electromagnetic showers initiated by bunches of 28.5 GeV electrons. The light yield is compared with the expected and observed depth profiles of ionization in…
The Cherenkov Telescope Array Observatory (CTAO) is the next-generation observatory for high energy \gamma-ray astronomy with unprecedented sensitivity and accuracy. Accurate estimation and mitigation of systematic uncertainties are crucial…
Measuring the temperature and abundance patterns of clouds in the interstellar medium (ISM) provides an observational basis for models of the physical conditions within the clouds, which play an important role in studies of star and planet…
The possibility to use Cherenkov light measurements with Cherenkov telescope to study atmospheric processes is shown. Cherenkov light from extensive air showers is obtained using Monte Carlo simulations with CORSIKA code. Different…
Nighttime monitoring of the aerosol content of the lower atmosphere is a challenging task, because appropriate reference natural light sources are lacking. Here we show that the anthropogenic night sky brightness due to city lights can be…
The effective observation time of Imaging Air Cherenkov Telescopes (IACTs) plays an important role in the detection of gamma-ray sources, especially when the expected flux is low. This time is strongly limited by the atmospheric conditions.…
Polarimetric observations of the twilight sky are effective for the investigations of scattering properties of the atmosphere at different altitudes. Modern computer technique allows to reduce the influence of multiple scattering on the…