English
Related papers

Related papers: Atmospheric Refractive Electromagnetic Wave Bendin…

200 papers

The footprint of radio emission from extensive air showers is known to exhibit asymmetries due to the superposition of geomagnetic and charge-excess radiation. For inclined air showers a geometric early-late effect disturbs the signal…

Instrumentation and Methods for Astrophysics · Physics 2020-09-01 Felix Schlüter , Marvin Gottowik , Tim Huege , Julian Rautenberg

Reference systems and frames are crucial for high precision absolute astrometric work, and their foundations must be well-defined. The current frame, the International Celestial Reference Frame, will be discussed: its history, the use of…

Astrophysics · Physics 2009-11-10 E. B. Fomalont

High-precision pulsar timing requires accurate corrections for dispersive delays of radio waves, parametrized by the dispersion measure (DM), particularly if these delays are variable in time. In a previous paper we studied the Solar-wind…

Analog beamforming holds great potential for future terahertz (THz) communications due to its ability to generate high-gain directional beams with low-cost phase shifters. However, conventional analog beamforming may suffer substantial…

Signal Processing · Electrical Eng. & Systems 2026-03-26 Yike Xie , Weidong Mei , Dong Wang , Yingqi Wen , Zhi Chen , Jun Fang , Wei Guo , Boyu Ning

Doppler radars are routinely used for the remote sensing of oceanic surface currents and atmospheric wind profiles. Even though they operate at different frequencies and address different media, they follow very similar processing for the…

Atmospheric and Oceanic Physics · Physics 2021-02-02 Baptiste Domps , Julien Marmain , Charles-Antoine Guérin

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

The signatures of waves are seen during many high-quality ground-based refractive stellar occultations by solar system atmospheres. We present a new forward-modeling technique for ground-based stellar occultations based on wavelet…

Earth and Planetary Astrophysics · Physics 2025-09-15 Leslie A. Young , Michael J. Person

Atmospheric density profiles as well as several light absorption and scattering processes depend on geographic position and are generally time-variable. Their impact on the atmospheric Cherenkov technique in general (imaging or non-imaging)…

Astrophysics · Physics 2008-11-26 Konrad Bernloehr

The accuracy of astrometric observations conducted via a space-borne optical interferometer orbiting the Earth is expected to approach a few microarcseconds. Data processing of such extremely high-precision measurements requires access to a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sergei M. Kopeikin , N. V. Shuygina , M. V. Vasilyev , E. I. Yagudina , L. I. Yagudin

The axis tilt of light beam in optical system would introduce the dispersion of orbital angular momentum (OAM) spectrum. To deal with it, a two-step method is proposed and demonstrated. First, the tilt angle of optical axis is identified…

Optics · Physics 2020-04-27 Peng Zhao , Shikang Li , Yu Wang , Xue Feng , Kaiyu Cui , Fang Liu , Wei Zhang , Yidong Huang

By observing bright and compact astronomical sources while also taking data with the 183 GHz Water Vapour Radiometers, ALMA will be able to measure the `empirical' relationship between fluctuations in the phase of the astronomical signal…

Instrumentation and Methods for Astrophysics · Physics 2009-07-28 Bojan Nikolic

In ground based astronomical observations, atmospheric dispersion shifts the image of the object at different wavelengths due to the wavelength-dependent index of refraction of the atmosphere. Thus, using an Atmospheric Dispersion Corrector…

Instrumentation and Methods for Astrophysics · Physics 2019-12-06 Bachar Wehbe , Alexandre Cabral , Gerardo Avila

Radio detection is now an established technique for the study of ultra-high-energy (UHE) cosmic rays with energies above $\sim10^{17}$ eV. The next-generation of radio experiments aims to extend this technique to the observation of UHE…

High Energy Astrophysical Phenomena · Physics 2025-05-14 Marion Guelfand , Valentin Decoene , Olivier Martineau-Huynh , Simon Prunet , Matías Tueros , Oscar Macias , Aurélien Benoit-Lévy

The emerging space-air-ground integrated network has attracted intensive research and necessitates reliable and efficient aeronautical communications. This paper investigates terahertz Ultra-Massive (UM)-MIMO-based aeronautical…

Information Theory · Computer Science 2021-03-04 Anwen Liao , Zhen Gao , Dongming Wang , Hua Wang , Hao Yin , Derrick Wing Kwan Ng , Mohamed-Slim Alouini

The unprecedented quality of the observations available from the Atacama Large Millimetre/sub-millimetre Array (ALMA) calls for analysis methods making the best of them. Reconstructing in space the morphology and kinematics of radio sources…

Solar and Stellar Astrophysics · Physics 2016-09-07 P. N. Diep , N. T. Phuong , D. T. Hoai , P. T. Nhung , N. T. Thao , P. Tuan-Anh , P. Darriulat

Weather forecasting is a fundamental task in spatiotemporal data analysis, with broad applications across a wide range of domains. Existing data-driven forecasting methods typically model atmospheric dynamics over a fixed short time…

Machine Learning · Computer Science 2026-04-01 Jindong Tian , Yifei Ding , Ronghui Xu , Hao Miao , Chenjuan Guo , Bin Yang

In this work we use solar observations with the ALMA radio telescope at the wavelength of 1.21 mm. The aim of the analysis is to improve understanding of the solar chromosphere, a dynamic layer in the solar atmosphere between the…

Solar and Stellar Astrophysics · Physics 2018-12-19 R. Brajša , D. Sudar , I. Skokic , A. O. Benz , M. Kuhar , A. Kobelski , S. Wedemeyer , S. M. White , H. -G. Ludwig , M. Temmer , S. H. Saar , C. L. Selhorst

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

Of particular interest for radio and hard X-ray diagnostics of accelerated electrons during solar flares is the understanding of the basic non-linear mechanisms regulating the relaxation of electron beams propagating in turbulent plasmas.…

Space Physics · Physics 2015-03-06 Nicolas H. Bian , Eduard P. Kontar , Heather Ratcliffe

The Atacama Large Millimeter/submillimeter Array remains the largest mm radio interferometer observatory world-wide. It is now conducting its 11th observing cycle. In our previous paper presented at this conference series in 2020, we…

Instrumentation and Methods for Astrophysics · Physics 2024-08-09 Dirk Petry , María Díaz Trigo , Rüdiger Kneissl , Ignacio Toledo , Atsushi Miyazaki , Toshinobu Takagi , Ashley Barnes , Francesca Bonanomi
‹ Prev 1 3 4 5 6 7 10 Next ›