English
Related papers

Related papers: High spatial resolution FeXII observations of sola…

200 papers

The C II 133.5 nm multiplet has been observed by NASA's Interface Region Imaging Spectrograph (IRIS) in unprecedented spatial resolution. The aims of this work are to characterize these new observations of the C II lines, place them in…

Solar and Stellar Astrophysics · Physics 2015-10-30 Bhavna Rathore , Tiago M. D. Pereira , Mats Carlsson , Bart De Pontieu

We use 3D radiation magnetohydrodynamic models to investigate how the thermodynamic quantities in the simulation are encoded in observable quantities, thus exploring the diagnostic potential of the 133.5 nm lines. We find that the line core…

Solar and Stellar Astrophysics · Physics 2015-09-30 Bhavna Rathore , Mats Carlsson , Jorrit Leenaarts , Bart De Pontieu

We investigate the scaling properties of the long-range temporal evolution and intermittency of SDO/AIA intensity observations in four solar environments: an active region core, a weak emission region, and two core loops. We use two…

Solar and Stellar Astrophysics · Physics 2016-11-15 Ana Cristina Cadavid , Yeimy J. Rivera , John K. Lawrence , Damian J. Christian , Peter J. Jennings , A. Franco Rappazzo

Studying Doppler shifts provides deeper insights into the flow of mass and energy in the solar atmosphere. We perform a comprehensive measurement of Doppler shifts in the transition region and its center-to-limb variation (CLV) in the…

Solar and Stellar Astrophysics · Physics 2023-03-01 Abhishek Rajhans , Durgesh Tripathi , Vinay L. Kashyap , James A. Klimchuk , Avyarthana Ghosh

We analyze coordinated Hinode XRT and EIS observations of a non-flaring active region to investigate the thermal properties of coronal plasma taking advantage of the complementary diagnostics provided by the two instruments. In particular…

Solar and Stellar Astrophysics · Physics 2015-05-20 Paola Testa , Fabio Reale , Enrico Landi , Ed DeLuca , Vinay Kashyap

To investigate the interstellar medium (ISM) and Galactic cosmic rays (CRs) in the solar neighborhood, we analyzed ${\gamma}$-ray data by Fermi Large Area Telescope (LAT) for five nearby molecular cloud regions. Our data includes the…

High Energy Astrophysical Phenomena · Physics 2025-06-23 Tsunefumi Mizuno , Katsuhiro Hayashi , Hinako Ochi , Igor V. Moskalenko , Elena Orlando , Andrew W. Strong

The Interface Region Imaging Spectrograph (IRIS) of the NASA small explorer mission provides significantly more complete and higher resolution spectral coverage of the dynamical conditions inside the chromosphere and transition region (TR)…

Solar and Stellar Astrophysics · Physics 2015-10-28 E. Tavabi , S. Koutchmy , L. Golub

The relationships among coronal loop structures at different temperatures is not settled. Previous studies have suggested that coronal loops in the core of an active region are not seen cooling through lower temperatures and therefore are…

Solar and Stellar Astrophysics · Physics 2011-02-11 Ignacio Ugarte-Urra , Harry P. Warren , David H. Brooks

We present a survey of coronal forbidden lines detected in Far Ultraviolet Spectroscopic Explorer (FUSE) spectra of nearby stars. Two strong coronal features, Fe XVIII 974 A and Fe XIX 1118 A, are observed in 10 of the 26 stars in our…

Solar active regions contain a broad range of temperatures, with the thermal plasma distribution often observed to peak in the few millions of kelvin. Differential emission measure (DEM) analysis can allow instruments with diverse…

The excess broadening of high-temperature spectral lines, long observed near the tops of flare arcades, is widely considered to result from magnetohydrodynamic (MHD) turbulence. According to different theories, plasma turbulence is also…

Solar and Stellar Astrophysics · Physics 2024-07-18 William Ashfield , Vanessa Polito , Sijie Yu , Hannah Collier , Laura Hayes

The infrared solar spectrum contains a wealth of physical data about the Sun and is being explored using modern detectors and technology with new ground-based solar telescopes. One such instrument will be the ground-based Cryogenic Near-IR…

Solar and Stellar Astrophysics · Physics 2022-06-22 Aatiya Ali , Alin Paraschiv , Kevin Reardon , Philip Judge

High resolution spectral observations of transition region spectral lines capture the signatures of energy deposition and redistribution at the boundary between the lower and upper atmosphere, and have significant relevance for…

Solar and Stellar Astrophysics · Physics 2026-05-06 Paola Testa , Bart De Pontieu , Kyuhyoun Cho , Thomas Ayres

The frequency of heating events in the corona is an important constraint on the coronal heating mechanisms. Observations indicate that the intensities and velocities measured in active region cores are effectively steady, suggesting that…

Solar and Stellar Astrophysics · Physics 2015-05-28 Amy Winebarger , Joan Schmelz , Harry Warren , Steve Saar , Vinay Kashyap

The spectroscopic observations presented here were acquired during the 2017 August 21 total solar eclipse with a three-channel partially multiplexed imaging spectrometer (3PAMIS) operating at extremely high orders ($>$ 50). The 4 $R_\odot$…

Solar and Stellar Astrophysics · Physics 2024-03-18 Yingjie Zhu , Shadia R. Habbal , Adalbert Ding , Bryan Yamashiro , Enrico Landi , Benjamin Boe , Sage Constantinou , Michael Nassir

IRIS data allow us to study the solar transition region (TR) with an unprecedented spatial resolution of 0.33 arcsec. On 2013 August 30, we observed bursts of high Doppler shifts suggesting strong supersonic downflows of up to 200 km/s and…

In this study we combine the multiwavelength ultraviolet -- optical (Solar Dynamics Observatory, SDO) and radio (Nobeyama Radioheliograph, NoRH) observations to get further insight into space-frequency distribution of oscillations at…

Solar and Stellar Astrophysics · Physics 2015-05-13 D. Y. Kolobov , N. I. Kobanov , A. A. Chelpanov , A. A. Kochanov , S. A. Anfinogentov , S. A. Chupin , I. I. Myshyakov , V. E. Tomin

Contamination from singly ionized iron emission is one of the greatest obstacles to determining the intensity of emission lines in the UV and optical wavelength ranges. This study presents a comprehensive analysis of the FeII emission in…

The solar corona is orders of magnitude hotter than the underlying photosphere, but how the corona attains such high temperatures is still not understood. Soft X-ray (SXR) emission provides important diagnostics for thermal processes in the…

Solar and Stellar Astrophysics · Physics 2015-09-15 Amir Caspi , Thomas N. Woods , Harry P. Warren

Context. Studying the kinematic and dynamic evolution of fast eruptive events from the middle to high solar corona is a primary objective of the Metis coronagraph on Solar Orbiter. During perihelion, Metis acquires visible light images at a…