English
Related papers

Related papers: 3-D extent of the main ionospheric trough--a case …

200 papers

In this paper, we investigate full-wave computed radar tomography (CRT) using a rubble-pile asteroid model in which a realistic shape (Itokawa) is coupled with a synthetic material composition and structure model. The aim is to show that…

Earth and Planetary Astrophysics · Physics 2019-09-12 Liisa-Ida Sorsa , Mika Takala , Patrick Bambach , Jakob Deller , Esa Vilenius , Sampsa Pursiainen

It is well known that a 3D ray tracing algorithm furnishes the ray's coordinates, the three components of the wave vector and the calculated group time delay of the wave along the path. The latter quantity can be compared with the measured…

We investigate the possibility of detecting extensive air showers by the radar technique. Considering a bistatic radar system and different shower geometries, we simulate reflection of radio waves off the static plasma produced by the…

In this paper we study the presence of irregularities and scintillation in relation to the nightside part of a long-lived, Sun-aligned transpolar arc on 15 January 2015. The arc was observed in DMSP UV and particle data and lasted at least…

Ratchet models are prominent candidates to describe the transport phenomenum in nature in the absence of external bias. This work analyzes the parameter space of a discrete ratchet model and gives direct connections between chaotic domains…

Chaotic Dynamics · Physics 2011-11-08 Alan Celestino , Cesar Manchein , Holokx A. Albuquerque , Marcus W. Beims

The ESO Imaging Survey (EIS) presented in early issues of the Messenger, and with up-to-date information on the ongoing observations available on the Web (http://www.eso.org/eis), is a concerted effort by ESO and the Member State community…

Compton scatter tomography is an emerging technique with attractive applications in several fields in imaging such as non-destructive testing and medical scanning. In this paper, we introduce a novel modality in three dimensions with a…

Numerical Analysis · Mathematics 2022-03-18 Javier Cebeiro , Cecilia Tarpau , Marcela Morvidone , Diana Rubio , Mai Nguyen

From the prevention of natural disasters such as landslide and avalanches, to the enhancement of energy efficiencies in chemical and civil engineering industries, understanding the collective dynamics of granular materials is a fundamental…

Applied Physics · Physics 2020-10-14 Felix Rech , Kai Huang

China's Tianwen-1 Mars orbiter successfully imaged the third interstellar object, 3I/ATLAS, during its close encounter with Mars using the onboard HiRIC CMOS camera. This is China's first deep-space observation of an astronomical object.…

Data collected with Polrad swept frequency analyzer during almost 2.5 years of Interball-2 mission are used to investigate the directivity properties of AKR observed in the Northern Hemisphere. In contrast with the previous, mostly…

Astrophysics · Physics 2015-06-24 R. Schreiber

We present a detailed light curve analysis of publicly available V band observations of 62 binary stars, mostly contact binaries, obtained by the All Sky Automated Survey (ASAS)-3 project between 2000 and 2009. Eclipsing binaries are…

Solar and Stellar Astrophysics · Physics 2015-05-20 Sukanta Deb , Harinder P. Singh

Cosmic rays have valuable information about universe surroundings us. Finding energy, mass and arrival direction of primary cosmic ray particle are the most important aspects of extensive air shower studies. In order to determine these…

Instrumentation and Methods for Astrophysics · Physics 2011-03-17 H. Hedayati Kh. , A. Anvari , M. Bahmanabadi , M. Khakian Ghomi , J. Samimi

A chiral metastructure composed of spatially separated double semi-periodic helices is proposed and investigated theoretically and experimentally in this Letter. Chirality-dependent electromagnetically induced transparency (EIT) and a slow…

Classical Physics · Physics 2018-09-03 Bo Yan , Fan Gao , Hongfeng Ma , Kesong Zhong , Bin Lv , Naibo Chen , Pinggen Cai , Ziran Ye , Yun Li , Chenghua Sui , Tao Xu , Chenghua Ma , Qiang Lin

Active regions (ARs) are the main sources of variety in solar dynamic events. Automated detection and identification tools need to be developed for solar features for a deeper understanding of the solar cycle. Of particular interest here…

We have determined the spatiotemporal characteristics of the magnetosphere-ionosphere (M-I) coupling using auroral imaging. Observations at fixed positions for an extended period of time are provided by a ground-based all-sky imager…

Space Physics · Physics 2017-06-07 B. K. Humberset , J. W. Gjerloev , M. Samara , R. G. Michell

This paper proposes fast and novel methods to jointly estimate the target's unknown 3D shape and dynamics. Measurements are noisy and sparsely distributed 3D points from a light detection and ranging (LiDAR) sensor. The methods utilize…

Signal Processing · Electrical Eng. & Systems 2020-02-05 Benjamin Naujoks , Patrick Burger , Hans-Joachim Wuensche

In the effort to obtain low cost routine space debris observations in low Earth orbit, ESA plans to utilise the radar facilities of the European Incoherent Scatter Scientific Association. First demonstration measurements were performed from…

Astrophysics · Physics 2009-11-07 M. Landgraf , R. Jehn , W. Flury

Eclipsing binary systems play a vital role in astrophysics, as they provide a direct means of measuring fundamental stellar parameters. By combining high-precision space-based observations with ground-based multicolor photometric data,…

Solar and Stellar Astrophysics · Physics 2025-06-12 N. Alan , M. Alpsoy , Y. Kilic

In sequel to Moradi et al. [2009, ApJ, 690, L72], we employ two established numerical forward models (a 3D ideal MHD solver and MHD ray theory) in conjunction with time-distance helioseismology to probe the lateral extent of wave-speed…

Solar and Stellar Astrophysics · Physics 2011-01-04 H. Moradi , S. M. Hanasoge