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Related papers: Twilight observations with MASS-DIMM

200 papers

At the AMANDA South Pole site, four new holes were drilled to depths 2050 m to 2180 m and instrumented with 86 photomultipliers (PMTs) at depths 1520-2000 m. Of these PMTs 79 are working, with 4-ns timing resolution and noise rates 300 to…

Astrophysics · Physics 2007-05-23 L. Bergstrom

Far-UV observations in and near the Hubble Deep Fields demonstrate that the Space Telescope Imaging Spectrograph (STIS) can potentially obtain unique and precise measurements of the diffuse far-ultraviolet background. Although STIS is not…

Imaging atmospheric Cherenkov telescopes (IACTs) are equipped with sensitive photomultiplier tube (PMT) cameras. Exposure to high levels of background illumination degrades the efficiency of and potentially destroys these photo-detectors…

We describe the use of partially overlapping galaxies to provide direct measurements of the effective absorption in galaxy disks, independent of assumptions about internal disk structure. The non-overlapping parts of the galaxies and…

Astrophysics · Physics 2007-05-23 Raymond E. White , William C. Keel , Christopher J. Conselice

Beam Emission Spectroscopy (BES) measurements of ion-scale density fluctuations in the MAST tokamak are used to show that the turbulence correlation time, the drift time associated with ion temperature or density gradients, the particle…

The present paper investigates and discusses the ability of the Hartmann test with 4-aperture DIMM to measure the atmospheric primary aberrations which, in turn, can be used for calculation of the atmospheric coherence time. Through…

Instrumentation and Methods for Astrophysics · Physics 2011-03-09 Ramin Shomali , Sadollah Nasiri , Ahmad Darudi

The asteroseismic modelling of solar-like stars has proved to be valuable in constraining dark matter. In this work we study for the first time the influence of asymmetric dark matter (ADM) in the evolution of a subgiant star (KIC 8228742)…

Solar and Stellar Astrophysics · Physics 2021-09-28 João Rato , José Lopes , Ilídio Lopes

We present a method to map the artificial sky brightness across large territories in astronomical photometric bands with a resolution of approximately 1 km. This is useful to quantify the situation of night sky pollution, to recognize…

Astrophysics · Physics 2009-10-31 P. Cinzano , F. Falchi , C. D. Elvidge , K. E. Baugh

We have realised a simple prototype system to perform searches for short timescale optical transients, utilising the novel drift scan imaging technique described by Tingay (2020). We used two coordinated and aligned cameras, with an overlap…

High Energy Astrophysical Phenomena · Physics 2021-01-27 S. J. Tingay , W. Joubert

In usual measurement with the Senarmont method using a conventional polarization microscope, the azimuth angle of the analyzer at extinction of the emerging light is detected by naked eyes. If the intensity of light is measured as a…

Instrumentation and Detectors · Physics 2016-11-29 Atsushi Mori , Ryosuke Tomita

One of the scientific goals of the Large Synoptic Survey Telescope (LSST) is to measure the evolution of dark energy by measuring subtle distortions of galaxy shapes due to weak gravitational lensing caused by the evolving dark matter…

Instrumentation and Methods for Astrophysics · Physics 2018-07-27 Claire-Alice Hébert , Bruce Macintosh , Patricia R. Burchat

The slow light effects of an amplitude modulated Gaussian (AMG) pulse in a cesium atomic vapor are presented. In a single-$\Lambda$ type electromagnetically induced transparency (EIT) medium, more severe distortion is observed for an AMG…

Quantum Physics · Physics 2009-01-21 Wenzhuo Tang , Bin Luo , Yu Liu , Hong Guo

In this paper we present results of a short-term optical monitoring of 13 blazars. The objects were monitored mostly in the R-band for a total of ~ 160 hours between 2006 and 2011. We study the nature of the short-term variations and show…

High Energy Astrophysical Phenomena · Physics 2013-11-21 R. Bachev , E. Semkov , A. Strigachev , Alok C. Gupta , Haritma Gaur , B. Mihov , S. Boeva , L. Slavcheva-Mihova

Seeing, the angular size of stellar images blurred by atmospheric turbulence, is a critical parameter used to assess the quality of astronomical sites. Median values at the best mid-latitude sites are generally in the range of…

Instrumentation and Methods for Astrophysics · Physics 2020-07-31 Bin Ma , Zhaohui Shang , Yi Hu , Keliang Hu , Yongjiang Wang , Xu Yang , Michael C. B. Ashley , Paul Hickson , Peng Jiang

Continuous weak or fuzzy measurement of the Rabi oscillation of a two level atom subjected to a $\pi-$pulse of a resonant light field is simulated numerically. We thereby address the question whether it is possible to measure characteristic…

Quantum Physics · Physics 2007-05-23 J. Audretsch , Th. Konrad , M. Mensky

The approximate nature of the adaptive-optics time constant measurements with MASS is examined. The calibration coefficient C derived from numerical simulations of polychromatic scintillation shows dependence on the height of the turbulence…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 Andrei Tokovinin

Characterization of atmospheric turbulence is essential to understanding image quality of astronomical telescopes and applying adaptive optics systems. In this study, the vertical distributions of optical turbulence at the Peak Terskol…

Instrumentation and Methods for Astrophysics · Physics 2024-07-02 A. Y. Shikhovtsev , C. Qing , E. A. Kopylov , S. A. Potanin , P. G. Kovadlo

Cloud cover plays a pivotal role in assessing observational conditions for astronomical site-testing. Except for the fraction of observing time, its fragmentation also wields a significant influence on the quality of nighttime sky clarity.…

Instrumentation and Methods for Astrophysics · Physics 2023-11-27 Gu Wen-bo , Xu Jing , Feng Guo-jie , Zhang Xuan , Wang Le-tian , Wang Xin-liang , Ali Esamdin , Shen li-xian

Since the early days of experimental particle physics photomultipliers (PMTs) have played an important role in the detector design. Thanks to their capability of fast photon counting, PMTs are extensively used in the new-generation of…

Instrumentation and Detectors · Physics 2016-08-24 C. Bozza , T. Chiarusi , M. Costa , F. Di Capua , V. Kulikovskiy , R. Mele , P. Migliozzi , C. M. Mollo , C. Pellegrino , G. Riccobene , D. Vivolo