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Interferometric measurements of the radio emission of extensive air showers allow reconstructing cosmic-ray properties. A recent simulation study with an idealised detector promised measurements of the depth of the shower maximum…

Instrumentation and Methods for Astrophysics · Physics 2022-12-16 Felix Schlüter , Tim Huege

Radio astronomical imaging using aperture synthesis telescopes requires deconvolution of the point spread function as well as calibration of the instrumental characteristics (primary beam) and foreground (ionospheric/atmospheric) effects.…

Instrumentation and Methods for Astrophysics · Physics 2011-11-24 Juan M. Uson , William D. Cotton

We present a new calibration method based on cross-correlations with WMAP and apply it to data from the Atacama Cosmology Telescope (ACT). ACT's observing strategy and map making procedure allows an unbiased reconstruction of the modes in…

In the past two decades, a rebirth of interest in low-frequency radio astronomy for 21 cm tomography of the Epoch of Reionization, has given rise to a new class of radio interferometers with $N \gg 100$ antennas. The availability of…

Instrumentation and Methods for Astrophysics · Physics 2022-08-11 Deepthi Gorthi

This paper describes a concept for the high-accuracy absolute calibration of the instrumental polarization introduced by the primary mirror of a large-aperture telescope. This procedure requires a small aperture with polarization…

Astrophysics · Physics 2009-11-10 H. Socas-Navarro

We present the design, fabrication and measured performance of a hierarchical sinuous-antenna phased array coupled to transition-edge-sensor (TES) bolometers for measurements of the cosmic microwave background (CMB). To efficiently cover a…

Instrumentation and Methods for Astrophysics · Physics 2017-11-08 Ari Cukierman , Adrian T. Lee , Christopher Raum , Aritoki Suzuki , Benjamin Westbrook

In this lecture, we describe a number of advanced gain calibration techniques. In particular, self-calibration is an important tool in interferometric imaging at all wavelengths. It allows the observer to determine and remove residual phase…

Instrumentation and Methods for Astrophysics · Physics 2018-05-15 Crystal L. Brogan , Todd R. Hunter , Ed B. Fomalont

In 21-cm experimental cosmology, accurate characterization of a radio telescope's antenna beam response is essential to measure the 21-cm signal. Computational electromagnetic (CEM) simulations estimate the antenna beam pattern and…

Instrumentation and Methods for Astrophysics · Physics 2024-08-30 Joshua J. Hibbard , Bang D. Nhan , David Rapetti , Jack O. Burns

New and upcoming radio interferometers will produce unprecedented amounts of data that demand extremely powerful computers for processing. This is a limiting factor due to the large computational power and energy costs involved. Such…

Instrumentation and Methods for Astrophysics · Physics 2018-01-31 Sarod Yatawatta , Faruk Diblen , Hanno Spreeuw , L. V. E. Koopmans

We correlate the positions of radio galaxies in the FIRST survey with the CMB lensing convergence estimated from the Atacama Cosmology Telescope over 470 square degrees to determine the bias of these galaxies. We remove optically…

Muons produced in Extensive Air Showers (EAS) generate ring-like images in Imaging Atmospheric Cherenkov Telescopes when travelling near parallel to the optical axis. From geometrical parameters of these images, the absolute amount of light…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 A. M. W. Mitchell , V. Marandon , R. D. Parsons

Observationally, weak lensing has been served so far by optical surveys due to the much larger number densities of background galaxies achieved, which is typically by two to three orders of magnitude compared to radio. However, the high…

Instrumentation and Methods for Astrophysics · Physics 2016-03-18 Marzia Rivi , Lance Miller , Sphesihle Makhathini , Filipe Batoni Abdalla

We describe a system being developed for measuring the shapes of the mirrors of the Fred Young Submillimeter Telescope (FYST), now under construction for the CCAT Observatory. "Holographic" antenna-measuring techniques are an efficient and…

Instrumentation and Methods for Astrophysics · Physics 2021-03-16 Xiaodong Ren , Pablo Astudillo , Urs U. Graf , Richard E. Hills , Sebastian Jorquera , Bojan Nikolic , Stephen C. Parshley , Nicolás Reyes , Lars Weikert

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

Integrated optics are used to achieve astronomical interferometry inside robust and compact materials, improving the instrument's stability and sensitivity. In order to perform differential phase measurements at the H$\alpha$ line (656.3…

Measurements of cosmic microwave background (CMB) anisotropies by interferometers offer several advantages over single-dish observations. The formalism for analyzing interferometer CMB data is well developed in the flat-sky approximation,…

Astrophysics · Physics 2008-11-26 Emory F. Bunn , Martin White

With the advent of infrared long-baseline interferometers with more than two telescopes, both the size and the completeness of interferometric data sets have significantly increased, allowing images based on models with no a priori…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Stéphanie Renard , Eric Thiébaut , Fabien Malbet

Next-generation radio interferometers, such as the Square Kilometre Array (SKA), will revolutionise our understanding of the universe through their unprecedented sensitivity and resolution. However, to realise these goals significant…

Instrumentation and Methods for Astrophysics · Physics 2017-11-20 Luke Pratley , Jason D. McEwen , Mayeul d'Avezac , Rafael E. Carrillo , Alexandru Onose , Yves Wiaux

The measurement of magnitudes with different filters in photometric surveys gives access to cosmological distances and parameters. However, for current and future large surveys like the ZTF, DES, HSC or LSST, the photometric calibration…

Instrumentation and Methods for Astrophysics · Physics 2024-07-03 Jérémy Neveu , Dylan Kuhn , Thierry Souverin , LEMAITRE collaboration

As a new generation radio telescope, the Allen Telescope Array (ATA) is a prototype for the square kilometer array (SKA). Here we describe recently developed design constraints for the ATA digital signal processing chain as a case study for…

Instrumentation and Methods for Astrophysics · Physics 2012-11-29 G. R. Harp
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