English
Related papers

Related papers: Doppler shift oscillations from a hot line observe…

200 papers

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

This paper reports the results of a survey of Doppler shift oscillations measured during solar flares in emission lines of S XV and Ca XIX with the Bragg Crystal Spectrometer (BCS) on Yohkoh. Data from 20 flares that show oscillatory…

Astrophysics · Physics 2009-11-13 John T. Mariska

To study motions and oscillations in the solar chromosphere and at the transition region (TR) level we analyze some extreme Doppler shifts observed off-limb with the Interface Region Imaging Spectrograph (IRIS). Raster scans and slit-jaw…

Solar and Stellar Astrophysics · Physics 2019-09-25 E. Tavabi , S. Koutchmy

We analyzed high-cadence sit-and-stare observations acquired with the Hinode/EIS spectrometer and HXR measurements acquired with RHESSI during an M-class flare. During the flare impulsive phase, we observe no significant flows in the cooler…

Solar and Stellar Astrophysics · Physics 2016-03-09 P. Gömöry , A. M. Veronig , Y. Su , M. Temmer , J. K. Thalmann

Recent observations from the Extreme-ultraviolet Imaging Spectrometer (EIS) on board Hinode have shown that low density areas on the periphery of active regions are characterized by strong blue-shifts at 1 MK. These Doppler shifts have been…

Solar and Stellar Astrophysics · Physics 2015-05-19 Ignacio Ugarte-Urra , Harry P. Warren

Studying the Doppler shifts and the temperature dependence of Doppler shifts in moss regions can help us understand the heating processes in the core of the active regions. In this paper we have used an active region observation recorded by…

Solar and Stellar Astrophysics · Physics 2015-06-04 Durgesh Tripathi , Helen E. Mason , James A. Klimchuk

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…

Here, we study the temperature structure of flaring and non-flaring coronal loops, using extracted loops from images taken in six extreme ultraviolet (EUV) channels recorded by Atmospheric Imaging Assembly (AIA)/ Solar Dynamic Observatory…

Solar and Stellar Astrophysics · Physics 2022-03-14 Narges Fathalian , Seyedeh Somayeh Hosseini Rad , Nasibeh Alipour , Hossein Safari

We report on the first Interface Region Imaging Spectrograph (IRIS) study of cool transition region loops. This class of loops has received little attention in the literature. A cluster of such loops was observed on the solar disk in active…

Solar and Stellar Astrophysics · Physics 2015-09-09 Zhenghua Huang , Lidong Xia , Bo Li , Maria S. Madjarska

We perform Differential Emission Measure (DEM) analysis of an M7.7 flare that occurred on 2012 July 19 and was well observed by the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamic Observatory. Using the observational data with…

Solar and Stellar Astrophysics · Physics 2015-06-19 J. Q. Sun , X. Cheng , M. D. Ding

In order to better understand the possibility of coronal heating by MHD waves, we analyze Fe xii 195.12{\AA} data observed with EUV Imaging Spectrometer (EIS) onboard Hinode. We performed a Fourier analysis of EUV intensity and Doppler…

Solar and Stellar Astrophysics · Physics 2015-05-19 Naomasa Kitagawa , Takaaki Yokoyama , Shinsuke Imada , Hirohisa Hara

We exploit the high spatial resolution and high cadence of the Interface Region Imaging Spectrograph (IRIS) to investigate the response of the transition region and chromosphere to energy deposition during a small flare. Simultaneous…

Solar and Stellar Astrophysics · Physics 2016-09-28 Harry P. Warren , Jeffrey W. Reep , Nicholas A. Crump , Paulo J. A. Simoes

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

Using a new type of oscillation map, made from the radio spectra by the wavelet technique, we study the 18 April 2014 M7.3 flare (SOL2014-04-18T13:03:00L245C017). We find a quasi-periodic character of this flare with periods in the range…

Solar and Stellar Astrophysics · Physics 2017-07-19 M. Karlicky , J. Rybak , C. Monstein

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

Slow magnetoacoustic waves were first detected in hot ($>$6 MK) flare loops by the SOHO/SUMER spectrometer as Doppler shift oscillations in Fe XIX and Fe XXI lines. Recently, such longitudinal waves have been found by SDO/AIA in the 94 and…

Solar and Stellar Astrophysics · Physics 2017-01-11 Tongjiang Wang , Leon Ofman , Xudong Sun , Elena Provornikova , Joseph M. Davila

We investigate the relationship between the blue shifts of a hot emission line and the nonthermal emissions in microwave and hard X-ray (HXR) wavelengths during the precursor of a solar flare on 2014 October 27. The flare precursor is…

Solar and Stellar Astrophysics · Physics 2018-02-21 Dong Li , Ying Li , Wei Su , Yu Huang , Zongjun Ning

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…

Strongly damped Doppler shift oscillations are observed frequently associated with flarelike events in hot coronal loops. In this paper, a review of the observed properties and the theoretical modeling is presented. Statistical measurements…

Solar and Stellar Astrophysics · Physics 2014-04-24 Tongjiang Wang

A complete understanding of Doppler shift in active region loops can help probe the basic physical mechanism involved into the heating of those loops. Here we present observations of upflows in coronal loops detected in a range of…

Solar and Stellar Astrophysics · Physics 2015-06-05 Durgesh Tripathi , Helen Mason , Giulio Del Zanna , Steven Bradshaw