Loading...
Search for:
observatories
0.006 seconds
Functional Design of a Coating System for the Telescope Mirrors, A Recognition to Telescope of Iranian National Observatory
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor) ; Khosroshahi, Habib (Co-Advisor)
Abstract
Functional design of coating system for the primary mirror of the Iranian National Observatory (INO) is done. This telescope has a 3.4 m primary mirror in diameter, made of Zerodur from Schott. Although similar coating systems are in use since years ago, this is the first attempt to design a system for such a large surface case in Iran. Systematic approach led us first to clarify and identifying the design requirements. Lower limit of 80% for reflectance on all wavelength range from 325-1000 nm, thickness of 100 nm with un-uniformity of 5 nm, adhesion enough to pass the selotape test and surface roughness of less than 8 nm. Study of the available methods for coating and selection of the best...
Optimization of dimensions and inner surface of water Cherenkov detector with one photomultiplier tube (PMT) for the Alborz observatory air shower array
, Article Astroparticle Physics ; Volume 35, Issue 12 , July , 2012 , Pages 792-796 ; 09276505 (ISSN) ; Khalaj, P ; Bahmanabadi, M ; Purmohammad, D ; Abdollahi, S ; Sharif University of Technology
2012
Abstract
In order to be more precise to find primary cosmic particles directions, nowadays detectors and data analysis for studying secondary particles in extensive air showers have an ongoing progress and water Cherenkov detector is considered as a secondary particles detector. Our aim in this paper is to optimize the size and the inner surface characteristic of a cylindrical water Cherenkov tank with one PMT in order to use at the Alborz observatory air shower array which consists of 20 plastic scintillation detectors and 10 water Cherenkov detectors. By comparing data gathered by tanks with diffusing and specular reflection inner surfaces, we show that the diffusing inner surface is more...
Search for Gamma-Ray events in ALBORZ observatory data
, Article 31st International Cosmic Ray Conference, ICRC 2009, Lodz, 7 July 2009 through 15 July 2009 ; 2009 ; Bayesteh, S ; Bahmanabadi, M ; Hedayati, H ; Sheidaei, F ; Anvari, A ; Samimi, J ; Sharif University of Technology
University of Lodz
2009
Abstract
At ALBORZ Observatory in Tehran (51° 200 , 35 ° 430' , 1200 m) we accumulated a complete year of data by a 4-fold square array of Water Cherenkov Detectors (WCDs) with the side 6.08 m. It is recorded about 800,000 fine EAS events from 2006/11/12 to 2007/11/20 by the approximate recording rate of 0.03. Time differences between each two, three, four, five and ... have a very good agreement with gammafunction, which shows the correct random nature of the events. Of course we expect that about less than 1% of the EAS events (≤9000 events) be electromagnetic and naturally not random, but the contribution is so small. Then by Farley/Storey procedure [1] we found a signature of real sidereal data....
The power of environmental observatories for advancing multidisciplinary research, outreach, and decision support: the case of the minnesota river basin
, Article Water Resources Research ; Volume 55, Issue 4 , 2019 , Pages 3576-3592 ; 00431397 (ISSN) ; Dolph, C ; Baker, A ; Bevis, M ; Cho, S. J ; Czuba, J. A ; Dalzell, B ; Danesh Yazdi, M ; Hansen, A. T ; Kelly, S ; Lang, Z ; Schwenk, J ; Belmont, P ; Finlay, J. C ; Kumar, P ; Rabotyagov, S ; Roehrig, G ; Wilcock, P ; Foufoula Georgiou, E ; Sharif University of Technology
Blackwell Publishing Ltd
2019
Abstract
Observatory-scale data collection efforts allow unprecedented opportunities for integrative, multidisciplinary investigations in large, complex watersheds, which can affect management decisions and policy. Through the National Science Foundation-funded REACH (REsilience under Accelerated CHange) project, in collaboration with the Intensively Managed Landscapes-Critical Zone Observatory, we have collected a series of multidisciplinary data sets throughout the Minnesota River Basin in south-central Minnesota, USA, a 43,400-km2 tributary to the Upper Mississippi River. Postglacial incision within the Minnesota River valley created an erosional landscape highly responsive to hydrologic change,...