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Related papers: Initial Observations of Sunspot Oscillations Excit…

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In this paper, we report our first-step results of high resolution He\,\textsc{i} 10830 \AA\ narrow-band imaging (bandpass: 0.5 {\AA}) of an M1.8 class two-ribbon flare on July 5, 2012. The flare was observed with the 1.6 meter aperture New…

Solar and Stellar Astrophysics · Physics 2016-10-31 Ya Wang , Yingna Su , Zhenxiang Hong , Zhicheng Zeng , Kaifan Ji , Philip R. Goode , Wenda Cao , Haisheng Ji

Solar flares are one of the main forces behind space weather events. However the mechanism that drives such energetic phenomena is not fully understood. The standard eruptive flare model predicts that magnetic reconnection occurs high in…

Solar and Stellar Astrophysics · Physics 2015-06-17 S. Imada , K. Aoki , H. Hara , T. Watanabe , L. K. Harra , T. Shimizu

We search for signatures of high-frequency oscillations in the upper solar photosphere and low chromosphere in the context of acoustic heating of outer stellar atmospheres. We use ultraviolet image sequences of a quiet center-disk area from…

Astrophysics · Physics 2009-06-23 A. G. de Wijn , R. J. Rutten , T. D. Tarbell

Sunspots contain multiple small-scale structures in the umbra and in the penumbra. Despite extensive research on this subject in pre-Hinode era multiple questions concerning fine-scale structures of sunspots, their formation, evolution and…

Solar and Stellar Astrophysics · Physics 2018-10-18 Sanjiv K. Tiwari

I report observations of unusually strong photospheric and chromospheric velocity oscillations in and near the leading sunspot of NOAA 10781 on 03 July 2005. I investigate an impinging wave as a possible origin of the velocity pattern, and…

Solar and Stellar Astrophysics · Physics 2015-03-17 C. Beck

Waves and oscillations are important solar phenomena, not only because they can propagate and dissipate energy in the chromosphere, but also because they carry information about the structure of the atmosphere in which they propagate. The…

Solar and Stellar Astrophysics · Physics 2022-01-26 Yi Chai , Dale E. Gary , Kevin P. Reardon , Vasyl Yurchyshyn

The X9.3 flare of September 6, 2017, was the most powerful flare of Solar Cycle 24. It generated strong white-light emission and multiple helioseismic waves (sunquakes). By using data from Helioseismic and Magnetic Imager (HMI) onboard the…

Solar and Stellar Astrophysics · Physics 2018-09-19 Ivan N. Sharykin , Alexander G. Kosovichev

Context. An analysis of the oscillations above sunspots was carried out using simultaneous ground-based and Solar Dynamics Observatory (SDO) observations (SiI 10827A, HeI 10830A, FeI 6173A, 1700A, HeII 304A, FeIX 171A). Aims. Investigation…

Solar and Stellar Astrophysics · Physics 2014-11-25 N. I. Kobanov , A. A. Chelpanov , D. Y. Kolobov

We present observations of a precursory signature that would be helpful for understanding the formation process of sunspot penumbrae. The Hinode Solar Optical Telescope successfully captured the entire evolution of a sunspot from the pore…

Solar and Stellar Astrophysics · Physics 2015-06-04 Toshifumi Shimizu , Kiyoshi Ichimoto , Yoshinori Suematsu

Solar flares are large explosions on the Sun's surface caused by a sudden release of magnetic energy. They are known to cause local short-lived oscillations travelling away from the explosion like water rings. Here we show that the energy…

Astrophysics · Physics 2009-11-13 C. Karoff , H. Kjeldsen

Solar Orbiter conducted a series of flare-optimised observing campaigns in 2024 utilising the Major Flare Solar Orbiter Observing Plan (SOOP). Dedicated observations were performed during two distinct perihelia intervals in March/April and…

We propose a method for diagnosing the physical conditions in the solar atmosphere using an increase in oscillation amplitudes resulting from minuscule solar flares. As an example, we consider a B2 flare, which caused a sharp short-lived…

Solar and Stellar Astrophysics · Physics 2022-01-05 Andrei Chelpanov , Nikolai Kobanov

The X2.2-class solar flare of February 15, 2011, produced a powerful sunquake event, representing a helioseismic response to the flare impact in the solar photosphere, which was observed with the HMI instrument on the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2015-05-28 Alexander G. Kosovichev

We present multiwavelength observations of a large-amplitude oscillation of a polar crown filament on 15 October 2002. The oscillation occurred during the slow rise (about 1 km/s) of the filament. It completed three cycles before sudden…

Astrophysics · Physics 2009-11-13 H. Isobe , D. Tripathi , A. Asai , R. Jain

The heating of the solar corona is one of the big questions in astrophysics. Rapid pulses called nanoflares are among the best candidate mechanisms. The analysis of the time variability of coronal X-ray emission is potentially a very useful…

Solar and Stellar Astrophysics · Physics 2012-01-27 S. Terzo , F. Reale , M. Miceli , R. Kano , S. Tsuneta , J. A. Klimchuk

Model computations of Delta Scuti stars, located in the vicinity of the red edge of the classical instability strip, suggest amplitudes of solar-like oscillations larger than in cooler models located outside the instability strip.…

Astrophysics · Physics 2009-11-07 R. Samadi , M. J. Goupil , G. Houdek

We present the first \emph{Solar Dynamics Observatory}/Atmospheric Imaging Assembly observations of the large-amplitude longitudinal (LAL) oscillations in the south and north parts (SP and NP) of a solar filament on 2012 April 7. Both…

Solar and Stellar Astrophysics · Physics 2015-06-11 Ting Li , Jun Zhang

We present observations of an eruptive solar flare on 2016 January 6 that occurred behind the solar limb from the perspective of the Earth, but was well observed by STEREO and the Solar Extreme Ultraviolet Monitor on the Mars Atmosphere and…

Solar Optical Telescope onboard Hinode observed a sunspot (AR 11836) with two light bridges (LBs) on 31 Aug 2013. We analysed a 2-hour \ion{Ca}{2} H emission intensity data set and detected strong 5-min oscillation power on both LBs and in…

Solar and Stellar Astrophysics · Physics 2015-06-22 Ding Yuan , Valery M. Nakariakov , Zhenghua Huang , Bo Li , Jiangtao Su , Yihua Yan , Baolin Tan

The major solar event on 2006 December 13 is characterized by the approximately simultaneous occurrence of a heap of hot ejecta, a great two-ribbon flare and an extended Earth-directed coronal mass ejection. We examine the magnetic field…

Astrophysics · Physics 2009-11-13 Jun Zhang , Leping Li , Qiao Song