An Extended Radio Counterpart of TeV J2032+4130?

We carried out a 5-pointing mosaic observation of TeV J2032+4130 at 1.4 and 4.8 GHz with the VLA in April of 2003. The analysis of the 4.8GHz data indicate weak wispy shell-like radio structure(s) which are at least partially non-thermal. The radio data is compatible with one or more young supernova remnants or perhaps the signature of large scale cluster shocks in this region induced by the violent action of the many massive stars in Cyg OB2.Comment: Proc. 1st GLAST Symp. Feb 5-8, 2007, Stanford C

Analysis of factors influencing the electricity (capacity) price growth in the energy market of the Siberian Federal District

One of the main competitive advantages of the Russian Federation in the industrial products world markets is the relatively low prices for electricity sold on the domestic market for the industry sectors. Low electricity prices for energy-intensive industrial sectors, such as ferrous and non-ferrous metallurgy, mining, oil extraction and refining, etc., allow Russian economy to occupy a dominant position in various areas of world markets, and industries are able to maintain financial stability indicators and finance modernization and technical re-equipment programs. In the fourth quarter of 2021 and the first quarter of 2022, on the territory of the Siberian United Energy System, which includes consumers of the Siberian Federal District, an increase in prices for electricity supplied to end consumers, primarily industry, was revealed. In March 2022, the increase in electricity prices compared to the same period of the previous year, in the Krasnoyarsk Krai was 18.2 %, in the Republic of Khakassia – 13.1 %. In other regions of Russia over the specified period, the increase in final electricity prices for industry averaged 2.6 %. Thus, the empirical analysis carried out in the article revealed that electricity prices in the regions of the Siberian Federal District actually began to approach the average electricity prices in other federal districts of Russia

Adakite-like granitoids of Songkultau: A relic of juvenile Cambrian arc in Kyrgyz Tien Shan

The early Paleozoic Terskey Suture zone, located in the southern part of the Northern Tien Shan domain in Kyrgyzstan, comprises tectonic slivers of dismembered ophiolites and associated primitive volcanics and deep-marine sediments. In the Lake Songkul area, early-middle Cambrian pillow basalts are crosscut by the Songkultau intrusion of coarse-grained gneissose quartz diorites and tonalites with geochemical characteristics typical for high-SiO2 adakites (SiO2 ​> ​56 ​wt.%, Al2O3 ​> ​15 ​wt.%, Na2O ​> ​3.5 ​wt.% and high Sr/Y and La/Yb ratios). The Songkultau granitoids have positive initial εNd (+3.8 to +6.4) and εHf (+12.3 to +13.5) values indicating derivation from sources with MORB-like isotopic signature. Volcanic formations, surrounding the Songkultau intrusion, have geochemical affinities varying from ocean floor to island arc series. This rock assemblage is interpreted as a relic of an early-middle Cambrian primitive arc where the adakite-like granitoids were derived from partial melting of young and hot subducted oceanic crust. An age of 505 ​Ma, obtained for the Songkultau intrusion, shows that hot subduction under the Northern Tien Shan continued until middle Cambrian. The primitive arc complexes were obducted onto the Northern Tien Shan domain, where the Andean type continental magmatic arc developed in Cambrian and Ordovician. Formation of the Andean type arc was accompanied by uplift, erosion and deposition of coarse clastic sediments. A depositional age of ca. 470 Ma, obtained for the gravellites in the Lake Songkul area, is in agreement with the timing of deposition for lower Ordovician conglomerates elsewhere in the Northern Tien Shan, and corresponds to the main phase of the Andean type magmatism. The Songkultau adakites in association with surrounding ocean floor and island arc formations constitute a relic of a primitive Cambrian arc and represent a juvenile domain of substantial size identified so far within the predominantly crustal-derived terranes of Tien Shan. On a regional scale this primitive arc can be compared with juvenile Cambrian arcs of Kazakhstan, Gorny Altai and Mongolia.©2020 China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Low-Temperature Thermochronology of the Chatkal-Kurama Terrane (Uzbekistan-Tajikistan): Insights Into the Meso-Cenozoic Thermal History of the Western Tian Shan

The Chatkal-Kurama terrane represents a key region in understanding the tectonic evolution of the western Tian Shan. In this contribution, we present new thermochronological data (zircon [U-Th-Sm]/He, apatite fission track, and apatite [U-Th-Sm]/He) and the associated thermal history models for 30 igneous samples from the Chatkal-Kurama terrane within Uzbekistan and Tajikistan (west of the Talas-Fergana Fault) and integrate our data with published data from the central Tian Shan (east of the Talas-Fergana Fault). The Chatkal-Kurama terrane experienced a phase of rapid cooling during the Triassic-Jurassic at ca. 225–190 Ma, which we interpret as a far-field response to the closure of the Palaeo-Asian Ocean or the accretion of the Qiangtang terrane on to the Eurasian margin. In the Late Jurassic to the Early Cretaceous, the Chatkal-Kurama terrane experienced a period of tectonic stability and denudation, before transitioning into a period of marine incursions of the Paratethys Sea. In contrast, fast cooling is recorded for the Kyrgyz central Tian Shan to the east of the Talas-Fergana Fault. The differing thermal histories at either side of the Talas-Fergana Fault suggest that the fault induced a topographic divide during the Late Jurassic-Early Cretaceous, with high relief in the east (Kyrgyz Tian Shan) and low relief to the west (Uzbek-Tajik Tian Shan). Finally, the Chatkal-Kurama terrane experienced renewed tectonic activity since ca. 30 Ma, related with the distant India-Eurasia collision and Pamir indentation. The Cenozoic reactivation induced crustal tilting of the Chatkal-Kurama terrane, progressively exposing deeper rocks to the southwest

Evidence for Intergalactic Absorption in the TeV Gamma-Ray Spectrum of Mkn 501

The recent HEGRA observations of the blazar Mkn 501 show strong curvature in the very high energy gamma-ray spectrum. Applying the gamma-ray opacity derived from an empirically based model of the intergalactic infrared background radiation field (IIRF), to these observations, we find that the intrinsic spectrum of this source is consistent with a power-law: dN/dE~ E^-alpha with alpha=2.00 +/- 0.03 over the range 500 GeV - 20 TeV. Within current synchrotron self-Compton scenarios, the fact that the TeV spectral energy distribution of Mkn 501 does not vary with luminosity, combined with the correlated, spectrally variable emission in X-rays, as observed by the BeppoSAX and RXTE instruments, also independently implies that the intrinsic spectrum must be close to alpha=2. Thus, the observed curvature in the spectrum is most easily understood as resulting from intergalactic absorption.Comment: 7 pages, 1 figure, accepted in ApJ Letters 1999 April

Noncommutative electrodynamics and ultra high energy gamma rays

Plane waves in noncommutative classical electrodynamics (NCED) have a peculiar dispersion relation. We investigate the kinematical conditions on this deformed "mass shell" which come from ultra high energy gamma rays and discuss noncommutative dynamical effects on the gamma absorption by the infrared background and on the intrinsic spectrum. Finally we note that in NCED there is a strong correlation between the modified dispersion relation and the presence of dynamical effects in electromagnetic phenomena such as in the case of the synchrotron radiation. From this point of view, the limits on the typical energy scale of the violation of Lorentz invariance obtained by deformed dispersion relations and by assuming undeformed dynamical effects should be taken with some caution.Comment: Latex file, 7 pages, to be published in Europhysics Letter

Study on Cosmic Ray Background Rejection with a 30 m Stand-Alone IACT using Non-parametric Multivariate Methods in a sub-100 GeV Energy Range

During the last decade ground-based very high-energy gamma-ray astronomy achieved a remarkable advancement in the development of the observational technique for the registration and study of gamma-ray emission above 100 GeV. It is widely believed that the next step in its future development will be the construction of telescopes of substantially larger size than the currently used 10 m class telescopes. This can drastically improve the sensitivity of the ground-based detectors for gamma rays of energy from 10 to 100 GeV. Based on Monte Carlo simulations of the response of a single stand-alone 30 m imaging atmospheric Cherenkov telescope (IACT) the maximal rejection power against background cosmic ray showers for low energy gamma-rays was investigated in great detail. An advanced Bayesian multivariate analysis has been applied to the simulated Cherenkov light images of the gamma-ray- and proton-induced air showers. The results obtained here quantitatively testify that the separation between the signal and background images degrades substantially at low energies, and consequently the maximum overall quality factor can only be about 3.1 for gamma rays in the 10-30 GeV energy range. Various selection criteria as well as optimal combinations of the standard image parameters utilized for effective image separation have been also evaluated.Comment: Accepted for publication in the Journal of Physics