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Related papers: Evaluation of the ALMA Prototype Antennas

200 papers

We present high resolution (0.3") Atacama Large Millimeter Array (ALMA) 870um imaging of five z~1.5-4.5 X-ray detected AGN with luminosities of L(2-8keV)>10^42 erg/s. These data provide a >~20x improvement in spatial resolution over…

Astrophysics of Galaxies · Physics 2016-02-17 C. M. Harrison , J. M. Simpson , F. Stanley , D. M. Alexander , E. Daddi , J. R. Mullaney , M. Pannella , D. J. Rosario , Ian Smail

The Greenland Telescope project has recently participated in an experiment to image the supermassive black hole shadow at the center of M87 using Very Long Baseline Interferometry technique in April of 2018. The antenna consists of the 12-m…

Microstrip antennas are extensively used in spacecraft systems and other applications where they encounter a plasma environment. A detailed computational investigation of change in antenna radiation properties in the presence of plasma has…

Plasma Physics · Physics 2016-11-17 Hardik Vyas , Bhaskar Chaudhury , Sanjeev Gupta

We report on the first detection of pulsed radio emission from a radio pulsar with the ALMA telescope. The detection was made in the Band-3 frequency range (85-101 GHz) using ALMA in the phased-array mode developed for VLBI observations. A…

ALMA-IMF is a large program of the Atacama Large Millimeter/submillimeter Array (ALMA) that aims to determine the origin of the core mass function (CMF) of 15 massive Galactic protoclusters (~ 1.0-25.0 x 10^3 solar mass within ~ 2.5 x 2.5…

Devices that detect angle-of-arrival (AoA) over a wide field of view are crucial for various applications such as wireless communication and navigation. They are often installed on platforms with challenging mechanical and stealth…

Signal Processing · Electrical Eng. & Systems 2025-07-08 Idban Alamzadeh , Michael Inman , Mohammadreza F. Imani

We present the calibration and reduction of Event Horizon Telescope (EHT) 1.3mm radio wavelength observations of the supermassive black hole candidate at the center of the radio galaxy M87 and the quasar 3C 279, taken during the 2017 April…

Astrophysics of Galaxies · Physics 2019-07-08 The Event Horizon Telescope Collaboration

In previous articles, we described how electromagnetic waves emitted from objects in the sky are collected by the ALMA antennas (Anatomy of ALMA), and how they are combined in order to produce images. Before these images can be processed,…

Instrumentation and Methods for Astrophysics · Physics 2012-10-09 T. L. Wilson , R. Mauersberger , A. Hales

ALMA will revolutionize the study of star formation by providing a combination of angular resolution and sensitivity that far exceeds that of present instruments. I will focus on studies of relatively isolated cores that are forming…

Astrophysics · Physics 2007-05-23 Neal J. Evans

A micro-pulse lidar at eye-safe wavelength is constructed based on an up-conversion single-photon detector. The ultralow noise detector enables using integration technique to improve the signal-to-noise ratio of the atmospheric…

The precision measurements of the strong coupling constant, alphas, and its energy-scale dependence carried out at HERA by the H1 and ZEUS Collaborations are reviewed. An average value of alphas(Mz) = 0.1186 +- 0.0011 (exp.) +- 0.0050 (th.)…

High Energy Physics - Experiment · Physics 2015-06-25 Claudia Glasman

One of the main considerations in the ALMA Development Roadmap for the future of operations beyond 2030 is to at least double its on-sky instantaneous bandwidth capabilities. Thanks to the technological innovations of the past two decades,…

Compact and efficient optical antennas are fundamental components for many applications, including high-density fiber-chip coupling and optical phased arrays. Here we present the design of grating-based micro-antennas with perfectly…

We present ALMA Cycle 1 observations of the HH46/47 molecular outflow using combined 12m array and ACA observations. The improved angular resolution and sensitivity of our multi-line maps reveal structures that help us study the entrainment…

We report here Atacama Large Millimeter/submillimeter Array (ALMA) N$_2$H$^+$ (1-0) images of the Orion Molecular Cloud 2 and 3 (OMC-2/3) with high angular resolution (3'' or 1200 au) and high spatial dynamic range. Combining dataset from…

Astrophysics of Galaxies · Physics 2021-02-10 Nannan Yue , Di Li , Qizhou Zhang , Lei Zhu , Jonathan Henshaw , Diego Mardones , Zhiyuan Ren

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

Dust traps are the most promising mechanisms to explain the observed substructures in protoplanetary discs. In this work, we present high-angular resolution ($\sim$60 mas, 9.4 au) and high-sensitivity Atacama Large Millimetre/submillimetre…

The Atacama Large Millimetre/submillimetre Array (ALMA) is one of the largest and most complicated observatories ever built. Constructing and operating an observatory at high altitude (5000m) in a cost effective and safe manner, with…

Astrophysics · Physics 2009-11-13 Paola Andreani , Martin Zwaan

Existing and planned radiotelescopes working in the millimetre (mm) and sub-millimetre wavelengths range provide the possibility to be used for atmospheric line observations. To scrutinize this potential, we outline the differences and…

Earth and Planetary Astrophysics · Physics 2019-03-28 Nicola Schneider , Joachim Urban , Philippe Baron

Global 21cm experiments aim to measure the sky averaged HI absorption signal from cosmic dawn and the epoch of reionisation. However, antenna chromaticity coupling to bright foregrounds can introduce distortions into the observational data…

Instrumentation and Methods for Astrophysics · Physics 2021-11-12 Dominic Anstey , John Cumner , Eloy de Lera Acedo , Will Handley