English
Related papers

Related papers: Observations of Solar Doppler Shift Oscillations w…

200 papers

Recent observations in extreme-ultraviolet (EUV) wavelengths reveal a new late phase in some solar flares, which is seen as a second peak in warm coronal emissions ($\sim3$ MK) several tens of minutes to a few hours after the soft X-ray…

Solar and Stellar Astrophysics · Physics 2021-08-04 Y. Zhong , Y. Dai , M. D. Ding

Observations of the dynamics of solar coronal structures are necessary to investigate space weather phenomena and global heating of the corona. The profiles of high temperature lines emitted by the hot plasma are usually integrated by…

Solar and Stellar Astrophysics · Physics 2021-10-27 J. -M. Malherbe , P. Mein , F. Sayede , P. Rudawy , K. Phillips , F. Keenan , J. Rybak

Universal small-scale solar activity in quiet region are suggested to be a potential source of solar wind and the upper solar atmosphere. Here, with the high-resoltion 174 \AA~imaging observations from the Solar Orbiter/Extreme Ultraviolet…

Solar and Stellar Astrophysics · Physics 2024-12-19 Yadan Duan , Hechao Chen , Zhenyong Hou , Zheng Sun , Yuandeng Shen

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

We apply a new method to determine the magnetic field in coronal loops using observations of coronal loop oscillations. We analyze seven Doppler shift oscillation events detected by SUMER in the hot flare line Fe XIX to obtain oscillation…

Astrophysics · Physics 2008-11-26 Tongjiang Wang , Davina E. Innes , Jiong Qiu

We have previously found a temperature-dependent upflow in the dimming region following a coronal mass ejection (CME) observed by the {\it Hinode} EUV Imaging Spectrometer (EIS). In this paper, we reanalyzed the observations along with…

Solar and Stellar Astrophysics · Physics 2015-05-30 S. Imada , H. Hara , T. Watanabe , I. Murakami , L. K. Harra , T. Shimizu , E. G. Zweibel

The present solar cycle is particular in many aspects: it had a delayed rising phase, it is the weakest of the last 100 years, and it presents two peaks separated by more than one year. To understand the impact of these characteristics on…

Solar and Stellar Astrophysics · Physics 2017-11-08 A. J. Oliveira e Silva , C. L. Selhorst , P. J. A. Simões , C. G. Giménes de Castro

Prominence oscillations are one of interesting phenomena in the solar atmosphere, which can be utilized to infer the embedded magnetic field magnitude. We present here the transverse oscillations of two different prominences located at the…

Solar and Stellar Astrophysics · Physics 2022-08-17 Pooja Devi , Ramesh Chandra , Reetika Joshi , P. F. Chen , Brigitte Schmieder , Wahab Uddin , Yong-Jae Moon

Although the differential rotation rate on the solar surface has long been studied using optical and extreme ultraviolet (EUV) observations, associating these measurements to specific atmospheric heights remains challenging due to the…

Solar and Stellar Astrophysics · Physics 2025-07-04 Srinjana Routh , Anshu Kumari , Vaibhav Pant , Jaydeep Kandekar , Dipankar Banerjee , Mohd. Saleem Khan , Dibya Kirti Mishra

Spicules are intermittently rising above the surface of the Sun eruptions; EUV jets are now also reported in immediately above layers. The variation of spicule orientation with respect to the solar latitude, presumably reflecting the…

Solar and Stellar Astrophysics · Physics 2021-07-27 E. Tavabi , S. Koutchmy

Recurrent and propagating intensity perturbations are frequently observed in extreme ultraviolet (EUV) channels along coronal fan loops above sunspots, and these perturbations are suggested to be slow magnetoacoustic waves. Numerous studies…

Solar and Stellar Astrophysics · Physics 2025-02-26 Junwei Zhao , Tongjiang Wang , Ruizhu Chen

During the total solar eclipse of 11 July 2010, multi-slit spectroscopic observations of the solar corona were performed from Easter Island, Chile. To search for high-frequency waves, observations were taken at a high cadence in the green…

Solar and Stellar Astrophysics · Physics 2016-01-20 T. Samanta , J. Singh , G. Sindhuja , D. Banerjee

A comprehensive study of the physical parameters of active region fan loops is presented using the observations recorded with the Interface Region Imaging Spectrometer (IRIS), the EUV Imaging Spectrometer (EIS) on-board Hinode and the…

Solar and Stellar Astrophysics · Physics 2017-02-08 Avyarthana Ghosh , Durgesh Tripathi , G. R. Gupta , Vanessa Polito , Helen E. Mason , Sami K. Solanki

Observing the Sun at high time and spatial scales is a step towards understanding the finest and fundamental scales of heating events in the solar corona. The Hi-C instrument has provided the highest spatial and temporal resolution images…

Context: One of the most prominent processes suggested to heat the corona to well above 10^6 K builds on nanoflares, short bursts of energy dissipation. Aims: We compare observations to model predictions to test the validity of the…

Solar and Stellar Astrophysics · Physics 2015-11-04 Leping Li , Hardi Peter , Feng Chen , Jun Zhang

We report on the plasma properties of small-scale transient events identified in the quiet Sun, coronal holes and their boundaries. We use spectroscopic co-observations from SUMER/SoHO and EIS/Hinode combined with high cadence imaging data…

Solar and Stellar Astrophysics · Physics 2015-06-05 M. S. Madjarska , Z. Huang , J. G. Doyle , S. Subramanian

A significant impediment to solving the coronal heating problem is that we currently only observe active region (AR) loops in their cooling phase. Previous studies showed that the evolution of cooling loop densities and apex temperatures…

Solar and Stellar Astrophysics · Physics 2024-01-10 David H. Brooks , Jeffrey W. Reep , Ignacio Ugarte-Urra , John E. Unverferth , Harry P. Warren

The large uncertainties associated with measuring the amount of high temperature emission in solar active regions represents a significant impediment to making progress on the coronal heating problem. Most current observations at…

Solar and Stellar Astrophysics · Physics 2012-07-20 Luca Teriaca , Harry Warren , Werner Curdt

We present a Differential Emission Measure (DEM) analysis of the quiet solar corona on disk using data obtained by the Extreme-ultraviolet Imaging Spectrometer (EIS) on {\it Hinode}. We show that the expected quiet Sun DEM distribution can…

Solar and Stellar Astrophysics · Physics 2009-11-09 David H. Brooks , Harry P. Warren , David R. Williams , Tetsuya Watanabe

We performed a systematic study of the Doppler shifts and electron densities measured in an EUV bright point (hereafter BP) observed in more than 10 EUV lines with formation temperatures from log (T/K) p 4.5 to 6.3. Those parts of a BP seen…

Solar and Stellar Astrophysics · Physics 2011-02-11 Hui Tian , Werner Curdt , Eckart Marsch , Jiansen He