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Here we present a thermal emission spectrum of WASP-79b, obtained via Hubble Space Telescope Wide Field Camera 3 G141 observations as part of the PanCET program. As we did not observe the ingress or egress of WASP-79b's secondary eclipse,…

Sausage waves have been frequently reported in solar magnetic structures such as sunspots, pores, and coronal loops. However, they have not been unambiguously identified in photospheric bright points (BPs). Using high-resolution TiO image…

Solar and Stellar Astrophysics · Physics 2021-12-23 Yuhang Gao , Fuyu Li , Bo Li , Wenda Cao , Yongliang Song , Hui Tian , Mingzhe Guo

We survey the electron heat flux observed by the Parker Solar Probe (PSP) in the near-Sun environment at heliocentric distances of 0.125-0.25 AU. We utilized measurements from the Solar Wind Electrons Alphas and Protons and FIELDS…

The expansion with height of the solar photospheric magnetic field and the plasma flows is investigated for three isolated bright points (BPs). The BPs were observed simultaneously with 3 instruments at the GREGOR telescope: (1) filtergrams…

Solar and Stellar Astrophysics · Physics 2019-10-09 Christoph Kuckein

Recent observations by the Fermi satellite suggest that a photosphere emission component is contributing to the observed spectrum of many GRBs. One important question is whether the photosphere component can interpret the typical ``Band''…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Wei Deng , Bing Zhang

Magnetic bright points are small-scale magnetic elements ubiquitous across the solar disk, with the prevailing theory suggesting that they form due to the process of convective collapse. Employing a unique full Stokes spectropolarimetric…

Although Gamma Ray Bursts (GRBs) have been detected for many decades, the lack of knowledge regarding the radiation mechanism that produces the energetic flash of radiation, or prompt emission, from these events has prevented the full use…

High Energy Astrophysical Phenomena · Physics 2022-02-23 Tyler Parsotan , Davide Lazzati

We present the analysis of a high-resolution, high-quality sample of optical spectra for 76 subdwarf B (sdB) stars from the ESO Supernova Ia Progenitor Survey (SPY). Effective temperature, surface gravity, and photospheric helium abundance…

Astrophysics · Physics 2009-11-10 T. Lisker , U. Heber , R. Napiwotzki , N. Christlieb , Z. Han , D. Homeier , D. Reimers

We conduct a stacking analysis using 1.4 GHz NRAO VLA Sky Survey (NVSS) detections and Planck all-sky maps to estimate the differential source counts down to the few 100 $\mu$Jy level at 30, 44, 70 and 100 GHz. Consequently, we are able to…

Astrophysics of Galaxies · Physics 2018-07-11 Eric J. Murphy , Ranga-Ram Chary

We analyze observations from the Interface Region Imaging Spectrograph of the Mg II k line, the Mg II UV subordinate lines, and the O I 135.6 nm line to better understand the solar plage chromosphere. We also make comparisons with…

Solar and Stellar Astrophysics · Physics 2015-08-21 Mats Carlsson , Jorrit Leenaarts , Bart De Pontieu

We present new millimetre 43 GHz observations of a sample of radio-bright Planetary Nebulae. Such observations were carried out to have a good determination of the high-frequency radio spectra of the sample in order to evaluate, together…

Astrophysics · Physics 2009-11-13 G. Umana , P. Leto , C. Trigilio , C. S. Buemi , P. Manzitto , S. Toscano , S. Dolei , L. Cerrigone

Coronal bright points (BPs) are small-scale luminous features seen in the solar corona. Quasi-periodic brightenings are frequently observed in the BPs and are generally linked with underneath magnetic flux changes. We study the dynamics of…

Solar and Stellar Astrophysics · Physics 2015-05-05 Tanmoy Samanta , Dipankar Banerjee , Hui Tian

We study $e^{\pm}$ pair plasmas in pair equilibrium, which emit high energy radiation by thermal Comptonization of soft photons. We find that the maximum luminosity to size ratio of the source (i.e. the compactness) depends not only on the…

Astrophysics · Physics 2009-10-22 Gabriele Ghisellini , Francesco Haardt

An iterative method is presented for reconstructing the height-temperature profile of the solar atmosphere above a sunspot using multi-frequency spectro-polarimetric microwave observations. It is assumed that the emission is formed…

Solar and Stellar Astrophysics · Physics 2026-03-09 T. I. Kaltman , A. G. Stupishin , G. A. Makoev

Magnetic elements on the quiet sun are buffeted by convective flows that cause lateral motions on timescales of minutes. The magnetic elements can be observed as bright points (BPs) in the G band at 4305 {\AA}. We present observations of…

Astrophysics · Physics 2009-11-07 P. Nisenson , A. A. van Ballegooijen , A. G. de Wijn , P. Sutterlin

Six high-resolution TiO-band image sequences from the New Vacuum Solar Telescope (NVST) are used to investigate the properties of intergranular bright points (igBPs). We detect the igBPs using a Laplacian and morphological dilation…

Solar and Stellar Astrophysics · Physics 2016-05-25 Kai-Fan Ji , Jian-ping Xiong , Yong-yuan Xiang , Song Feng , Hui Deng , Feng Wang , Yun-Fei Yang

The contribution of the Unresolved Extragalactic Radio Sources to the diffuse brightness of the sky was evaluated using the source number - flux measurements available in literature. We first optimized the fitting function of the data based…

Astrophysics · Physics 2009-11-13 M. Gervasi , A. Tartari , M. Zannoni , G. Boella , G. Sironi

The photospheric emission in the prompt phase is the natural prediction of the original fireball model for gamma-ray burst (GRB) due to the large optical depth ($\tau >1$) at the base of the outflow, which is supported by the quasi-thermal…

High Energy Astrophysical Phenomena · Physics 2021-12-02 Yan-Zhi Meng , Jin-Jun Geng , Xue-Feng Wu

This work reports a peculiar and interesting train of microwave type III pair bursts in the impulsive rising phase of a solar flare on 2011 September 26. The observations include radio spectrometers at frequency of 0.80 - 2.00 GHz, hard…

Solar and Stellar Astrophysics · Physics 2016-09-28 Baolin Tan , Marian Karlicky , Hana Meszarosova , Larisa Kashapova , Jing Huang , Yan Yan , Eduard P. Kontar

Preflare activities contain critical information about the pre-cursors and causes of solar eruptions. Here we investigate the characteristics and origin of a group of broadband pulsations (BBPs) in the decimetric-metric wavelengths, taking…

Solar and Stellar Astrophysics · Physics 2023-06-14 Maoshui Lv , Baolin Tan , Ruisheng Zheng , Zhao Wu , Bing Wang , Xiangliang Kong , Yao Chen
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