English
Related papers

Related papers: Active Region Moss: Doppler Shifts from Hinode/EIS…

200 papers

We investigate the role of active region spicules in the mass balance of the solar wind and energy supply for heating the solar atmosphere. We use high cadence observations from the Solar Optical Telescope (SOT) onboard the Hinode satellite…

Solar and Stellar Astrophysics · Physics 2016-03-23 S. Zeighami , A. R. Ahangarzadeh Maralani , E. Tavabi , A. Ajabshirizadeh

The origin of solar transition region redshifts is not completely understood. Current research is addressing this issue by investigating three-dimensional magneto-hydrodynamic models that extend from the photosphere to the corona. By…

Solar and Stellar Astrophysics · Physics 2015-05-28 Pia Zacharias , Sven Bingert , Hardi Peter

During solar flares, a considerable portion of the flare atmosphere becomes heated; however, the energy deposition process is still unclear, especially in the lower solar atmosphere. Here, we present spectroscopic and imaging observations…

Solar and Stellar Astrophysics · Physics 2026-03-24 Girjesh Gupta , Ananya Rawat , Helen Mason , Robertus Erdélyi

Context. The carbon monoxide (CO) molecular line at around 46655 A in solar infrared spectra is often used to investigate the dynamic behavior of the cold heart of the solar atmosphere, i.e., sunspot oscillation, especially at the sunspot…

Solar and Stellar Astrophysics · Physics 2020-10-28 D. Li , X. Yang , X. Y. Bai , J. T. Su , Z. J. Ning , W. Cao , Y. Y. Deng

The Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode spacecraft observed flare footpoint regions coincident with a surge for a M3.7 flare observed on 25 September 2011 at N12 E33 in active region 11302. The flare was observed in…

Solar and Stellar Astrophysics · Physics 2015-10-30 George A. Doschek , Harry P. Warren , Brian R. Dennis , Jeffrey W. Reep , Amir Caspi

Here we present the study of a compact emission source during an X1.3 flare on 2022-March-30. Within a $\sim41$~s period (17:34:48 UT to 17:35:29 UT), IRIS observations show spectral lines of Mg II, C II and Si IV with extremely broadened,…

Solar and Stellar Astrophysics · Physics 2023-09-13 Yan Xu , Graham S. Kerr , Vanessa Polito , Nengyi Huang , Ju Jing , Haimin Wang

We study the non-thermal velocities in the quiet-sun using various high spatial, temporal, and spectral resolution observations from the Interface Region Imaging Spectrograph (IRIS). We focus our analysis on the transition region using the…

Solar and Stellar Astrophysics · Physics 2022-01-26 Yamini K. Rao , Giulio Del Zanna , Helen E. Mason

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…

We present the first results of sunspot oscillations from observations by the Interface Region Imaging Spectrograph. The strongly nonlinear oscillation is identified in both the slit-jaw images and the spectra of several emission lines…

The Interface Region Imaging Spectrograph (IRIS) has observed bright spots at the transition region footpoints associated with heating in the overlying loops, as observed by coronal imagers. Some of these brightenings show significant…

Solar and Stellar Astrophysics · Physics 2019-09-04 Fabio Reale , Paola Testa , Antonino Petralia , David R. Graham

We present plasma diagnostics of an EIT wave observed with high cadence in Hinode/EIS sit-and-stare spectroscopy and SDO/AIA imagery obtained during the HOP-180 observing campaign on 2011 February 16. At the propagating EIT wave front, we…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. M. Veronig , P. Gomory , I. W. Kienreich , N. Muhr , B. Vrsnak , M. Temmer , H. P. Warren

Doppler shifts in chromospheric and transition-region lines during solar flares are often interpreted as chromospheric condensation or evaporation. However, alternative sources of Doppler-shifted emission have been suggested, such as…

Solar and Stellar Astrophysics · Physics 2025-09-08 Luke H. Majury , Ryan O. Milligan

Plasma upflows with a Doppler shift exceeding -10 km/s at active region (AR) boundaries are considered potential sources of the nascent slow solar wind. We investigate the driving mechanisms of a pair of coronal upflow regions on the…

We investigate intensity variations and energy deposition in five coronal loops in active region cores. These were selected for their strong variability in the AIA/SDO 94 {\AA} intensity channel. We isolate the hot Fe XVIII and Fe XXI…

Solar and Stellar Astrophysics · Physics 2015-06-19 A. C. Cadavid , J. K. Lawrence , D. J. Christian , D. B. Jess , G. Nigro

Many models for coronal loops have difficulty explaining the observed EUV brightness of the transition region, which is often significantly less than theoretical models predict. This discrepancy has been addressed by a variety of approaches…

Solar and Stellar Astrophysics · Physics 2009-08-24 Bart De Pontieu , Viggo H. Hansteen , Scott W. McIntosh , Spiros Patsourakos

Emerging flux regions (EFRs) are known to exhibit various sporadic local heating events in the lower atmosphere. To investigate the characteristics of these events, especially to link the photospheric magnetic fields and atmospheric…

Solar and Stellar Astrophysics · Physics 2017-02-15 Shin Toriumi , Yukio Katsukawa , Mark C. M. Cheung

This study explores the Doppler shift at different wavelengths in the Interface Region Imaging Spectrograph (IRIS) solar spectrum and implements a comprehensive consideration of Doppler velocity oscillations in the IRIS channels. This…

Solar and Stellar Astrophysics · Physics 2024-06-18 Rayhaneh Sadeghi , Ehsan Tavabi

The Helioseismic Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) records line-of-sight Dopplergram images of convective flows on the surface. These images are used to obtain the multi-scale convective spectrum. We design…

Solar and Stellar Astrophysics · Physics 2021-08-09 Samarth G Kashyap , Shravan M Hanasoge

The extreme ultraviolet portion of the solar spectrum contains a wealth of diagnostic tools for probing the lower solar atmosphere in response to an injection of energy, particularly during the impulsive phase of solar flares. These include…

Solar and Stellar Astrophysics · Physics 2015-09-16 Ryan O. Milligan

In order to better understand the plasma supply and leakage at active regions, we investigated physical properties of the upflows from edges of active region NOAA AR10978 observed with the EUV Imaging Spectrometer (EIS) onboard Hinode. Our…

Solar and Stellar Astrophysics · Physics 2014-11-19 Naomasa Kitagawa
‹ Prev 1 4 5 6 7 8 10 Next ›