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In radio astronomy, the science output of a telescope is often limited by computational resources. This is especially true for transient and technosignature surveys that need to search high-resolution data across a large parameter space.…

Instrumentation and Methods for Astrophysics · Physics 2024-04-11 Danny C. Price

(Sub) mm VLBI observations are strongly hindered by limited sensitivity, with the fast tropospheric fluctuations being the dominant culprit. We predict great benefits from applying next-generation frequency phase transfer calibration…

Instrumentation and Methods for Astrophysics · Physics 2023-02-24 María J. Rioja , Richard Dodson , Yoshiharu Asaki

Foreground removal is a challenge for 21-cm tomography of the high redshift Universe. We use archival GMRT data (obtained for completely different astronomical goals) to estimate the foregrounds at a redshift ~ 1. The statistic we use is…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-12 Abhik Ghosh , Somnath Bharadwaj , Sk. Saiyad Ali , Jayaram N. Chengalur

A new spectrometer for the Green Bank Telescope (GBT) is being built jointly by the NRAO and the CASPER, University of California, Berkeley. The spectrometer uses 8 bit ADCs and will be capable of processing up to 1.25 GHz bandwidth from 8…

The 21 cm radiation of neutral hydrogen provides crucial information for studying the early universe and its evolution. To advance this research, countries have made significant investments in constructing large low-frequency radio…

Instrumentation and Methods for Astrophysics · Physics 2025-08-04 Ming-wei Qin , Rui Tang , Ying-hui Zhou , Chang-jun Lan , Wen-hao Fu , Huan Wang , Bao-lin Hou , Zamri , Jin-song Ping , Wen-jun Yang , Liang Dong

The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to survey the gamma-ray sky from 20 MeV to several hundreds of GeV. In this energy band there are no astronomical sources…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 The Fermi LAT Collaboration

Astronomers usually need the highest angular resolution possible, but the blurring effect of diffraction imposes a fundamental limit on the image quality from any single telescope. Interferometry allows light collected at widely-separated…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John D. Monnier , Ronald J. Allen

We introduce the cross spectrum based FRB (Fast Radio Burst) search method for VLBI observation. This method optimizes the fringe fitting scheme in geodetic VLBI data post processing, which fully utilizes the cross spectrum fringe phase…

Instrumentation and Methods for Astrophysics · Physics 2018-02-06 Lei Liu , Fengxian Tong , Weimin Zheng , Juan Zhang , Li Tong

We investigate a new scheme for astronomical spectrograph calibration using the laser frequency comb at the Solar Vacuum Tower Telescope on Tenerife. Our concept is based upon a single-mode fiber channel, that simultaneously feeds the…

Instrumentation and Methods for Astrophysics · Physics 2015-02-18 R A Probst , L Wang , H-P Doerr , T Steinmetz , T J Kentischer , G Zhao , T W Hänsch , Th Udem , R Holzwarth , W Schmidt

Aberration-corrected Scanning Transmission Electron Microscopy (STEM) has become an essential tool in understanding materials at the atomic scale. However, tuning the aberration corrector to produce a sub-{\AA}ngstr\"om probe is a complex…

This paper explores the potential for statistical epoch of reionization (EOR) measurements using wide field radio observations. New developments in low frequency radio instrumentation and signal processing allow very sensitive EOR…

Astrophysics · Physics 2009-11-10 Miguel F. Morales , Jacqueline Hewitt

This paper presents a new sample of BL Lac objects selected from a deep (30 mJy) radio survey of flat spectrum radio sources (the CLASS blazar survey, henceforth CBS). The sample is one of the largest well defined samples in the low power…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. J. M. Marcha , A. Caccianiga

Full-polarization primary beam patterns of MeerKAT antennas have been measured in L-band (856 to 1711 MHz) by means of radio holography using celestial targets. This paper presents the observed frequency dependent properties of these beams,…

Instrumentation and Methods for Astrophysics · Physics 2022-02-21 Mattieu de Villiers , William Cotton

The Thirty-Meter Telescope is an ambitious project to build a giant segmented mirror telescope with fully integrated adaptive optics systems that will produce diffraction-limited images. A powerful suite of instruments is being developed…

Astrophysics · Physics 2010-11-11 David Crampton , Luc Simard

We present two estimators to quantify the angular power spectrum of the sky signal directly from the visibilities measured in radio interferometric observations. This is relevant for both the foregrounds and the cosmological 21-cm signal…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-11 Samir Choudhuri , Somnath Bharadwaj , Abhik Ghosh , SK. Saiyad Ali

We describe phase-retrieval holography measurements of the 100-m diameter Green Bank Telescope using astronomical sources and an astronomical receiver operating at a wavelength of 7 mm. We use the technique with parameterization of the…

Astrophysics · Physics 2009-11-11 B. Nikolic , R. M. Prestage , D. S. Balser , C. J. Chandler , R. E. Hills

Energy consumption and hardware cost of signal digitization together with the management of the resulting data volume form serious issues for high-rate measurement systems with multiple sensors. Switching to binary sensing front-ends…

Instrumentation and Methods for Astrophysics · Physics 2019-07-16 Manuel S. Stein

We develop a pseudo power spectrum technique for measuring the lensing power spectrum from weak lensing surveys in both the full sky and flat sky limits. The power spectrum approaches have a number of advantages over the traditional…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-06 Chiaki Hikage , Masahiro Takada , Takashi Hamana , David Spergel

We presented the optimization procedures of the baffle mounted on the GroundBIRD telescope for measuring the polarization of the Cosmic Microwave Background~(CMB). The telescope employs dual mirror reflective telescopes installed in a…

We present new methods to minimize the systematic and random errors for measuring the transmission power spectrum from the Lyman-alpha forest. Sources of systematic errors explored include metal line contamination and continuum-fitting. We…

Astrophysics · Physics 2009-10-31 Lam Hui , Scott Burles , Uros Seljak , Robert E. Rutledge , Eugene Magnier , David Tytler