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Related papers: First supra-THz Heterodyne Array Receivers for Ast…

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We present an original heterodyne holography method for digital holography that relies on two-dimensional heterodyne detection to record the phase and the amplitude of a f ield. The technique has been tested on objects as much as 13 mm in…

Optics · Physics 2011-12-22 Frédérique Le Clerc , Laurent Collot , Michel Gross

Over the next few years the new radio telescopes, such as the Low Frequency Array (LOFAR) will greatly enhance our knowledge of the active history of the Universe. Large-area surveys with these new telescopes will no longer be dominated by…

Astrophysics · Physics 2007-05-23 Matt J. Jarvis

We experimentally observe the fast relaxation and relatively slow recombination dynamics of photogenerated electrons/holes in an epitaxial graphene-on-Si heterostructure under pumping with a 1550-nm, 80-fs pulsed fiber laser beam and…

We have analyzed the thermal and turbulent properties of the Low-Latitude Intermediate-Velocity Arch 1 (LLIV1). This was accomplished using archival H I emission and absorption data from two 21,cm line surveys: GHIGLS at $9.^\prime$4…

Astrophysics of Galaxies · Physics 2023-08-02 Luka Vujeva , Antoine Marchal , Peter G. Martin , Mukesh Taank

THz quantum cascade lasers based on a novel buried cavity geometry are demonstrated by combining double-metal waveguides with proton implantation. Devices are realised with emission at 2.8 THz, displaying ultra low threshold currents of 19…

Materials Science · Physics 2009-11-11 S. Dhillon , J. Alton , S. Barbieri , C. Sirtori , A. de Rossi , M. Calligaro , H. E. Beere , D. Ritchie

The Hydrogen Epoch of Reionization Array (HERA) is a new powerful radio-telescope, dedicated to the study of the early universe. Its main goal is to characterise the period of the universe where the first galaxies and stars started to form,…

Instrumentation and Methods for Astrophysics · Physics 2016-06-29 Nicolas Fagnoni , Eloy de Lera Acedo

The hydroxyl radical (OH) is found in various environments within the interstellar medium (ISM) of the Milky Way and external galaxies, mostly either in diffuse interstellar clouds or in the warm, dense environments of newly formed low-mass…

The Telescope Array (TA) of central Utah was designed to detect ultra-high-energy cosmic rays (UHECRs) and is the largest of its kind in the Northern hemisphere. Its capabilities, however, are not limited to extra-terrestrial sources.…

High Energy Astrophysical Phenomena · Physics 2023-08-11 Jackson Remington

We follow up on a report by Vacca et al. (2018) of 28 candidate large-scale diffuse synchrotron sources in an 8{\deg}$\times$8{\deg} area of the sky (centred at RA 5h0m0s Dec 5{\deg}48'0''). These sources were originally observed at 1.4 GHz…

Astrophysics of Galaxies · Physics 2022-05-27 Torrance Hodgson , Melanie Johnston-Hollitt , Benajmin McKinley , Tessa Vernstrom , Valentina Vacca

Time-harmonic far-field source array imaging in a two-dimensional waveguide is analyzed. A low-frequency situation is considered in which the diameter of the waveguide is slightly larger than the wavelength, so that the waveguide supports a…

Analysis of PDEs · Mathematics 2020-12-02 Josselin Garnier

The atmospheres of very cool, hydrogen-rich white dwarfs (Teff <6000 K) are challenging to models because of the increased complexity of the equation of state, chemical equilibrium, and opacity sources in a low-temperature, weakly ionized…

Solar and Stellar Astrophysics · Physics 2015-06-22 D. Saumon , J. B. Holberg , P. M. Kowalski

We describe the development of a noise-temperature testing capability for phased-array antennas operating in receive mode from 0.7 GHz to 1.8 GHz. Sampled voltages from each array port were recorded digitally as the zenith-pointing array…

Instrumentation and Methods for Astrophysics · Physics 2014-04-04 Aaron Chippendale , Douglas Hayman , Stuart Hay

The near-earth object camera (NEOCam) is a proposed infrared space mission designed to discover and characterize most of the potentially hazardous asteroids larger than 140 m in diameter that orbit near the Earth. NASA has funded technology…

The radio-wavelength detection of extensive air showers (EAS) initiated by cosmic-ray interactions in the Earth's atmosphere is a promising technique for investigating the origin of these particles and the physics of their interactions. The…

Instrumentation and Methods for Astrophysics · Physics 2021-03-29 A. Williamson , C. W. James , S. J. Tingay , S. J. McSweeney , S. M. Ord

This paper presents an ultra-low noise L-band radio astronomical cryogenic receiver for FAST telescope. The development of key low noise microwave parts of Coupling-LNA and conical quad-ridge OMT and reasonable system integration achieve…

Instrumentation and Methods for Astrophysics · Physics 2021-09-08 Hong-Fei Liu , Chuan He , Jin Wang , Peng Jiang , Sheng-Wang Wang , Yang Wu , Hang Zhang , Jin-You Song , Xiang-Wei Shi , Ming-Lei Guo

Experiments were performed with prototype antenna tiles for the Mileura Widefield Array--Low Frequency Demonstrator (MWA-LFD) to better understand the widefield, wideband properties of their design and to characterize the radio frequency…

Imaging applications in the terahertz (THz) frequency range are severely restricted by diffraction. Near-field scanning probe microscopy is commonly employed to enable mapping of the THz electromagnetic fields with sub-wavelength spatial…

Faraday rotation measurements of the solar corona made with the Very Large Array (VLA) at frequencies of 1465 and 1665 MHz are reported. The measurements were made along 20 lines of sight to 19 extragalactic radio sources in March and…

Astrophysics · Physics 2008-11-26 Laura D. Ingleby , Steven R. Spangler , Catherine A. Whiting
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