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

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In holography, the IR behavior of a quantum system at nonzero density is described by the near horizon geometry of an extremal charged black hole. It is commonly believed that for systems on $S^3$, this near horizon geometry is $AdS_2\times…

High Energy Physics - Theory · Physics 2023-03-22 Gary T. Horowitz , Maciej Kolanowski , Jorge E. Santos

We present in this study a mapping of the optical turbulence (OT) above different astronomical sites. The mesoscale model Meso-NH was used together with the Astro-Meso-Nh package and a set of diagnostic tools allowing for a full 3D…

Instrumentation and Methods for Astrophysics · Physics 2010-11-29 Franck Lascaux , Elena Masciadri , Susanna Hagelin

We test the utility of the OII 83.4 nm emission feature as a measure of ionospheric parameters. Observed with the Remote Atmospheric and Ionospheric Detection System (RAIDS) Extreme Ultraviolet Spectrograph on the International Space…

We detail new techniques for analysing ionospheric activity, using Epoch of Reionisation (EoR) datasets obtained with the Murchison Widefield Array (MWA), calibrated by the `Real-Time System' (RTS). Using the high spatial- and…

Instrumentation and Methods for Astrophysics · Physics 2017-08-30 C. H. Jordan , S. Murray , C. M. Trott , R. B. Wayth , D. A. Mitchell , M. Rahimi , B. Pindor , P. Procopio , J. Morgan

Aims. The main purpose of this paper is to study time delays between the light variations in different wavebands for a sample of quasars. Measuring a reliable time delay for a large number of quasars may help constraint the models of their…

Astrophysics · Physics 2009-11-13 Rumen S. Bachev

Three-minute oscillations over sunspot's umbra in AR 11131 were observed simultaneously in UV/EUV emission by SDO/AIA and in radio emission by Nobeyama Radioheliograph (NoRH). We use 24-hours series of SDO and 8-hours series of NoRH…

Solar and Stellar Astrophysics · Physics 2015-05-30 V. E. Reznikova , K. Shibasaki , R. A. Sych , V. M. Nakariakov

Context: Distant trans-Neptunian objects are subject to planetary perturbations and galactic tides. The former decrease with the distance, while the latter increase. In the intermediate regime where they have the same order of magnitude…

Earth and Planetary Astrophysics · Physics 2019-09-18 Melaine Saillenfest , Marc Fouchard , Takashi Ito , Arika Higuchi

Understanding the nonlinear relation between the shapes of halos or galaxies and the surrounding matter distribution is essential in accurate modeling of their intrinsic alignments. In the perturbative treatment, such nonlinear relation of…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-24 Kazuyuki Akitsu , Yin Li , Teppei Okumura

The LOw Frequency ARray (LOFAR) was used to track the propagation of a TID containing embedded plasma structures which generated type 1 asymmetric quasi periodic scintillations (QPS: Maruyama, 1991) over a distance of >1200 km across…

We consider using toroidal curved detectors to improve the performance of imaging optical systems. We demonstrate that some optical systems have an anamorphic field curvature. We consider an unobscured re-imaging three-mirror anastigmat as…

Instrumentation and Methods for Astrophysics · Physics 2018-06-22 Eduard Muslimov , Emmanuel Hugot , Marc Ferrari , Thibault Behaghel , Gerard R. Lemaitre , Melanie Roulet , Simona Lombardo

The heliosphere serves as a probe of interstellar material (ISM) close to the Sun. Measurements of ISM inside and outside of the heliosphere show that we reside in typical warm partially ionized ISM that can be successfully modeled using…

Astrophysics · Physics 2007-05-23 P. C. Frisch

In this study, we investigate the problem of tracking objects with unknown shapes using three-dimensional (3D) point cloud data. We propose a Gaussian process-based model to jointly estimate object kinematics, including position,…

Signal Processing · Electrical Eng. & Systems 2021-04-12 Murat Kumru , Emre Özkan

We propose a LSST Solar System near-Sun Survey, to be implemented during twilight hours, that extends the seasonal reach of LSST to its maximum as fresh sky is uncovered at about 50 square degrees per night (1500 sq. deg. per lunation) in…

A direct measurement of the expansion of W 3(OH) is made by comparing Very Large Array images taken about 10 yr apart. The expansion is anisotropic with a typical speed of 3 to 5 km/s, indicating a dynamical age of only 2300 yr. These…

Astrophysics · Physics 2009-10-30 Jonathan H. Kawamura , Colin R. Masson

We investigated the adsorption of iodine on silver (111) in ultra-high vacuum. Using low-temperature scanning tunneling microscopy (LT-STM) measurements we catalog the complex surface structures on the local scale. We identified three…

Materials Science · Physics 2022-04-13 Michael Dreyer , Joseph Murray , Robert E. Butera

As the number of known Galactic structures mounts thanks to the Gaia Space Telescope, it is now pertinent to study methods for disentangling structures occupying the same regions of the Milky Way. Indeed, understanding the precise form of…

Astrophysics of Galaxies · Physics 2024-03-14 Ziyuan Yin , Austin Hinkel

High spectral resolution observations of Venus were obtained with the TEXES instrument at NASA's Infrared Telescope Facility. These observations focus on a CO$_2$ absorption feature at 791.4 cm$^{-1}$ as the shape of this absorption feature…

Earth and Planetary Astrophysics · Physics 2022-07-26 Rohini S Giles , Thomas K Greathouse , Patrick G J Irwin , Thérèse Encrenaz , Amanda Brecht

The radio pulse from a pulsar can be temporally broadened by multipath scattering in the interstellar medium and by instrumental effects within the radio telescope. The observed pulse shape is a convolution of the intrinsic one with the…

Instrumentation and Methods for Astrophysics · Physics 2016-03-09 M. M. McKinnon

In this paper, we explore the feasibility of using communication signals for extended target (ET) tracking in an integrated sensing and communication (ISAC) system. The ET is characterized by its center range, azimuth, orientation, and…

Signal Processing · Electrical Eng. & Systems 2025-04-02 Yiqiu Wang , Meixia Tao , Shu Sun

A wide range of stellar explosions, including supernovae (SNe), tidal disruption events (TDE), and fast blue optical transients (FBOT), can occur in dusty environments initially opaque to the transient's optical/UV light, becoming visible…

High Energy Astrophysical Phenomena · Physics 2025-01-24 Semih Tuna , Brian D. Metzger , Yan-Fei Jiang , Christopher J. White
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