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Adaptive optics systems require a calibration procedure to operate, whether in closed loop or even more importantly in forward control. This calibration usually takes the form of an interaction matrix and is a measure of the response on the…

Instrumentation and Methods for Astrophysics · Physics 2021-01-15 Olivier Lai , Mark Chun , Ryan Dungee , Jessica Lu , Marcel Carbillet

We describe a process for cross-calibrating the effective areas of X-ray telescopes that observe common targets. The targets are not assumed to be "standard candles" in the classic sense, in that we assume that the source fluxes have…

Instrumentation and Methods for Astrophysics · Physics 2021-12-01 Herman L. Marshall , Yang Chen , Jeremy J. Drake , Matteo Guainazzi , Vinay L. Kashyap , Xiao-Li Meng , Paul P. Plucinsky , Peter Ratzlaff , David A. van Dyk , Xufei Wang

The ngVLA is a new interferometric radio astronomy facility with transformative capabilities, being developed by the National Radio Astronomy Observatory. It combines two orders of magnitude in frequency coverage, over 1.2 - 116 GHz, with…

Instrumentation and Methods for Astrophysics · Physics 2025-04-22 T. K. Sridharan , S. Bhatnagar , P. Jagannathan , K. Golap

Recent discoveries of dispersed, non-periodic impulsive radio signals with single-dish radio telescopes have sparked significant interest in exploring the relatively uncharted space of fast transient radio signals. Here we describe V-FASTR,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Randall B. Wayth , Walter F. Brisken , Adam T. Deller , Walid A. Majid , David R. Thompson , Steven J. Tingay , Kiri L. Wagstaff

Pulsed UV lasers can provide useful "testbeams" for observatories that use optical detectors, especially fluorescence detectors, to measure high energy cosmic-rays. The light observed by the detector is proportional to the energy of the…

Instrumentation and Methods for Astrophysics · Physics 2011-05-23 Lawrence Wiencke , Fernando Arqueros , John Compton , Maria Monasor , David Pilger , Jaime Rosado

Multiple instruments are pursuing constraints on dark energy, observing reionization and opening a window on the dark ages through the detection and characterization of the 21cm hydrogen line across the redshift spectrum, from nearby to…

Instrumentation and Methods for Astrophysics · Physics 2016-10-11 Daniel C. Jacobs , Jacob Burba , Judd Bowman , Abraham R. Neben , Benjamin Stinnett , Lauren Turner

Most calibration methods operate at the logit level, implicitly assuming that miscalibration can be corrected without changing the underlying representation. We challenge this assumption and propose \textbf{Calibration Attention (CalAttn)},…

Computer Vision and Pattern Recognition · Computer Science 2026-01-21 Wenhao Liang , Wei Emma Zhang , Lin Yue , Miao Xu , Mingyu Guo , Olaf Maennel , Weitong Chen

Very Large Area gamma-ray Space Telescope (VLAST) is the next-generation flagship space observatory for high-energy gamma-ray detection proposed by China. The observation energy range covers from MeV to TeV and beyond, with acceptance of 10…

Radio interferometric imaging aims to estimate an unknown sky intensity image from degraded observations, acquired through an antenna array. In the theoretical case of a perfectly calibrated array, it has been shown that solving the…

Instrumentation and Methods for Astrophysics · Physics 2017-07-25 Audrey Repetti , Jasleen Birdi , Arwa Dabbech , Yves Wiaux

In August 2015, the CALorimetric Electron Telescope (CALET), designed for long exposure observations of high energy cosmic rays, docked with the International Space Station (ISS) and shortly thereafter began tocollect data. CALET will…

Self-calibration methods with the CLEAN algorithm have been widely employed in Very Long Baseline Interferometry (VLBI) data processing in order to correct antenna-based amplitude and phase corruptions present in the data. However, human…

Instrumentation and Methods for Astrophysics · Physics 2024-10-02 Jong-Seo Kim , Aleksei S. Nikonov , Jakob Roth , Torsten A. Ensslin , Michael Janssen , Philipp Arras , Hendrik Mueller , Andrei P. Lobanov

Transforming the instrumental photometry of ground-based telescopes into a calibrated physical flux in a well-defined passband is a major challenge in astronomy. Along with the intrinsic instrumental difference between telescopes sharing…

Instrumentation and Methods for Astrophysics · Physics 2025-07-08 S. Garrappa , E. O. Ofek , S. Ben-Ami , D. Polishook , A. Gal-Yam , Y. Shvartzvald , A. Krassilchtchikov , R. Konno , E. Segre , Y. M. Shani , Y. Sofer-Rimalt , M. Engel , A. Blumenzweig

The central challenge in 21~cm cosmology is isolating the cosmological signal from bright foregrounds. Many separation techniques rely on the accurate knowledge of the sky and the instrumental response, including the antenna primary beam.…

The major cornerstone of future ground-based astronomy is imaging and spectroscopy at the diffraction limit using adaptive optics. To exploit the potential of current AO systems, we have begun a survey around bright stars to study…

Astrophysics · Physics 2007-05-23 R. I. Davies , M. Lehnert , A. J. Baker , S. Rabien

Optical interferometers increasingly use single-mode fibers as spatial filters to convert varying wavefront distortion into intensity fluctuations which can be monitored for accurate calibration of fringe amplitudes. Here I propose using an…

Astrophysics · Physics 2009-11-06 J. D. Monnier

We performed an automated comparison of the FIRST radio survey with the APM optical catalog to find radio lobes with optical counterparts. Based on an initial survey covering ~3000 square degrees, we selected a sample of 33 lens candidates…

Astrophysics · Physics 2009-10-31 J. Lehar , A. Buchalter , R. G. McMahon , C. S. Kochanek , T. W. B. Muxlow

Prompted by some inconsistencies in the photometry of the VISTA Variables in the V\'ia L\'actea (VVV) survey, we conduct a revision of the standard calibration procedure of VISTA data in the $J$, $H$, and $K_S$ passbands. Two independent…

Instrumentation and Methods for Astrophysics · Physics 2020-07-01 Gergely Hajdu , István Dékány , Márcio Catelan , Eva K. Grebel

The SKA will deliver orders of magnitude increases in sensitivity, but most astrometric VLBI observations are limited by systematic errors. In these cases improved sensitivity offers no benefit. The best current solution for improving the…

Instrumentation and Methods for Astrophysics · Physics 2019-07-04 Richard Dodson , María Rioja

In this paper we describe the routine photometric calibration of data taken with the VIRCAM instrument on the ESO VISTA telescope. The broadband ZYJHKs data are directly calibrated from 2MASS point sources visible in every VISTA image. We…

The development of sensitive large format imaging arrays for the infrared promises to provide revolutionary capabilities for space astronomy. For example, the Infrared Array Camera (IRAC) on SIRTF will use four 256 x 256 arrays to provide…

Astrophysics · Physics 2016-08-30 D. J. Fixsen , S. H. Moseley , R. G. Arendt