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Related papers: CHARA Array Delay Lines: Upgrades, Performance and…

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Recent advances in photonics have revived the interest in intensity interferometry for astronomical applications. The success of amplitude interferometry in the early 1970s, which is now mature and producing spectacular astrophysical…

The Low Frequency Array (LOFAR) is an ideal instrument to conduct deep extragalactic surveys. It has a large field of view and is sensitive to large scale and compact emission. It is, however, very challenging to synthesize thermal noise…

Of the over 450 exoplanets known to date, more than 420 of them have been discovered using radial velocity studies, a method that tells nothing about the inclination of the planet's orbit. Because it is more likely that the companion is a…

The next generation of very long baseline interferometry (VLBI) is stepping into the era of microarcsecond ($\mu$as) astronomy, and pushing astronomy, especially astrometry, to new heights. VLBI with the Square Kilometre Array (SKA),…

Astrophysics of Galaxies · Physics 2024-04-24 Yingjie Li , Ye Xu , Jingjing Li , Shuaibo Bian , Zehao Lin , Chaojie Hao , Dejian Liu

The past decade has seen the rise of various radio astronomy arrays, particularly for low-frequency observations below 100MHz. These developments have been primarily driven by interesting and fundamental scientific questions, such as…

Instrumentation and Methods for Astrophysics · Physics 2016-01-28 Raj Thilak Rajan , Albert-Jan Boonstra , Mark Bentum , Marc Klein-Wolt , Frederik Belien , Michel Arts , Noah Saks , Alle-Jan van der Veen

Interferometric arrays seeking to measure the 21 cm signal from the Epoch of Reionization must contend with overwhelmingly bright emission from foreground sources. Accurate recovery of the 21 cm signal will require precise calibration of…

MIRC-X and MYSTIC are six-telescope near-infrared beam (1.08-2.38 ${\mu}$m) combiners at the CHARA Array on Mt Wilson CA, USA. Ever since the commissioning of MIRC-X (J and H bands) in 2018 and MYSTIC (K bands) in 2021, they have been the…

Up to now, the completion of an ALMA interferometric observation is determined based on the achievement of a given shape and size of the synthesized beam and the noise RMS in the representative spectral range. This approach with respect to…

Instrumentation and Methods for Astrophysics · Physics 2020-12-17 Dirk Petry , María Díaz Trigo , Rüdiger Kneissl , Ignacio Toledo , Stefano Facchini

In this contribution we report on our work to increase the spectral range of the Michigan Infrared Combiner-eXeter (MIRC-X) instrument at the CHARA array to allow for dual H and J band interferometric observations. We comment on the key…

The Very Large Array is undergoing a major upgrade that will attain an order of magnitude improvement in continuum sensitivity across 1 to 50 GHz with instantaneous bandwidths up to 8 GHz in both polarizations. The new WIDAR correlator…

Instrumentation and Methods for Astrophysics · Physics 2010-11-04 Sean M. Dougherty , Rick Perley

The Atacama Large Millimeter/submillimeter Array (ALMA), presently under construction, is a revolutionary astronomical interferometer, that will operate at (sub)millimeter wavelengths. With unprecedented sensitivity, resolution, and imaging…

Instrumentation and Methods for Astrophysics · Physics 2010-10-19 V. Casasola , J. Brand

Fluctuating properties of the atmosphere, and in particular its water vapour content, give rise to phase fluctuations of astronomical signals which, if uncorrected, lead to rapid deterioration of performance of (sub)-mm interferometers on…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Bojan Nikolic , Rosie C. Bolton , Sarah F. Graves , Richard E. Hills , John S. Richer

The next-generation Very Large Array (ngVLA) is an astronomical observatory planned to operate at centimeter wavelengths (25 to 0.26 centimeters, corresponding to a frequency range extending from 1.2 GHz to 116 GHz). The observatory will be…

This article presents a novel type of very long baseline astronomical interferometer that uses the fluctuations, as a function of time, of the intensity measured by a quadratic detector, which is a common type of astronomical detector. The…

Instrumentation and Methods for Astrophysics · Physics 2013-09-24 Ermanno F. Borra

With the development of astronomical facilities, large-scale time series data observed by these facilities is being collected. Analyzing anomalies in these astronomical observations is crucial for uncovering potential celestial events and…

Machine Learning · Computer Science 2024-03-18 Xinli Hao , Yile Chen , Chen Yang , Zhihui Du , Chaohong Ma , Chao Wu , Xiaofeng Meng

Debate over the planet occurrence rates around intermediate-mass stars has hinged on the accurate determination of masses of evolved stars, and has been exacerbated by a paucity of reliable, directly-measured fundamental properties for…

Here we describe the Compact Array Broadband Backend (CABB) and present first results obtained with the upgraded Australia Telescope Compact Array (ATCA). The 16-fold increase in observing bandwidth, from 2 x 128 MHz to 2 x 2048 MHz, high…

Radio interferometer arrays such as HERA consist of many close-packed dishes arranged in a regular pattern, giving rise to a large number of `redundant' baselines with the same length and orientation. Since identical baselines should see an…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 Samir Choudhuri , Philip Bull , Hugh Garsden

This paper presents the CosmicWeb-21cm array, a novel radio interferometer designed to overcome the key challenges in 21 cm cosmology. Its core innovations include: (1) a multi-scale nested geometry combining a hexagonal core with…

Instrumentation and Methods for Astrophysics · Physics 2026-03-03 Jiancheng Wang , Jirong Mao , Xiangming Cheng , Yigong Zhang , Jie Su , Xiaogu Zhong , Min Wang , Zhigang Zhang , Qingwei Wang , Yonghua Xu , Zhixuan Li , Longhua Qin , Zhengjun Zhang

The Atacama Large Millimeter/submillimeter Array (ALMA) combines large collecting area and location on a high dry site to provide it with unparalleled potential for sensitive millimeter/submillimeter spectral line observations. Its wide…

Astrophysics · Physics 2008-11-26 Alwyn Wootten
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