Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC.

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV.

Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C.

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models.

[Digital X-ray apparatus "Sibir'". Measurement of the value of a signal].

For objective measurement of digital detectors, the authors show it necessary to be limited to the quantum efficiency of recording for assessing the accuracy of measuring the value of a signal and to the frequency-contrast characteristics for estimating spatial accuracy. Since a computer is an integral part of the digital detector, this cannot be a basic obstacle to the application of the proposed procedure.

[Relaparotomy].

For a period of 1987-1995 yrs. the operations on a peritoneal cavity organs were performed in 14,718 patients. In 87 reoperated patients 93 relaparotomies were conducted.

[A digital radiographic device for medical diagnosis].

The paper outlines a digital radiographic device which records radiation by scanning with a one-dimensional multiwire proportional chamber connected on-line to a computer. The device drastically reduces a dosage load on patients, improves the diagnostic potentialities of projectional radiography, yields quantitative diagnostic information, creates special diagnostic programmes, has fast-access and fire-safe archives. The device may be used for general-purpose radiographic examinations and it has advantages when used instead of conventional fluorographs.