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Related papers: Light Walls Around Sunspots Observed by the Interf…

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IRIS (InfraRed Imaging Spectrograph) is a first light near-infrared diffraction limited imager and integral field spectrograph being designed for the future Thirty Meter Telescope (TMT). IRIS is optimized to perform astronomical studies…

Based on the \emph{Interface Region Imaging Spectrograph} observations, we study the response of a solar sunspot light wall to external disturbances. A flare occurrence near the light wall caused material to erupt from the lower solar…

Solar and Stellar Astrophysics · Physics 2016-12-21 Shuhong Yang , Jun Zhang , Robert Erdélyi

We observed rapid variability ($\lesssim 60$ s) at the footpoints of transient hot ($\sim 8-10$ MK) coronal loops in active region cores, with the Interface Region Imaging Spectrograph (IRIS). The high spatial ($\sim 0.33$ arcsec) and…

Solar and Stellar Astrophysics · Physics 2020-02-12 Paola Testa , Vanessa Polito , Bart De Pontieu

Lower atmospheric lines show peculiar profiles at the leading edge of ribbons during solar flares. In particular, increased absorption of the BBSO/GST \hei~10830~\AA\ line \citep[e.g.][]{Xu2016}, as well as broad and centrally reversed…

Solar and Stellar Astrophysics · Physics 2023-02-22 Vanessa Polito , Graham S. Kerr , Yan Xu , Viacheslav M. Sadykov , Juraj Lorincik

Context. In the upper atmosphere of the Sun observations show convincing evidence for crossing and twisted structures, which are interpreted as mutual helicity and self-helicity. Aims. We use observations with the new Interface Region…

Solar and Stellar Astrophysics · Physics 2014-10-29 Leping Li , Hardi Peter , Feng Chen , Jun Zhang

Comparison of photographic observations and vector-magnetograph measurements demonstrate, that the outer boundary of the sunspot penumbra --even in complex sunspot groups-- closely follows the 0.075T isogauss line of the total value of the…

Astrophysics · Physics 2009-11-07 B. Kalman

Spectropolarimetric time series data of the primary spot of active region NOAA 9448 were obtained in the Si I 10827 \AA line and the He I 10830 \AA multiplet with the Tenerife Infrared Polarimeter. Throughout the time series the…

Astrophysics · Physics 2007-05-23 D. Shaun Bloomfield , Andreas Lagg , Sami K. Solanki

The resonance lines of \ion{Si}{4} formed at $\lambda$1394 and 1403 {\AA} are the most critical for the diagnostics of the solar transition region in the observations of the Interface Region Imaging Spectrograph (IRIS). Studying the…

Solar and Stellar Astrophysics · Physics 2020-05-20 Durgesh Tripathi , V. N. Nived , Hiroaki Isobe , J. G. Doyle

We analyze a solar active region observed by the Hinode CaII H line using the time-distance helioseismology technique, and infer wave-speed perturbation structures and flow fields beneath the active region with a high spatial resolution.…

Solar and Stellar Astrophysics · Physics 2014-11-20 Junwei Zhao , Alexander G. Kosovichev , Takashi Sekii

The Interface Region Imaging Spectrograph(IRIS) with its high spatial and temporal resolution brings exceptional plasma diagnostics of solar chromospheric and coronal activity during magnetic reconnection. The aim of this work is to study…

Solar and Stellar Astrophysics · Physics 2021-01-20 Reetika Joshi , Brigitte Schmieder , Akiko Tei , Guillaume Aulanier , Juraj Lörinčík , Ramesh Chandra , Petr Heinzel

The formation mechanism of light bridges (LBs) is strongly related to the dynamic evolution of solar active regions (ARs). To study the relationship between LB formation and AR evolution phases, we employ 109 LB samples from 69 ARs in 2014…

Solar and Stellar Astrophysics · Physics 2024-02-22 Fuyu Li , Changhui Rao , Xinhua Zhao , Yang Guo , Xiaoying Gong , Yuhao Chen , Nanbin Xiang , Huaning Wang

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

It is well-known that light bridges inside a sunspot produce small-scale plasma ejections and transient brightenings in the chromosphere, but the nature and origin of such phenomena are still unclear. Utilizing the high-spatial and high…

Solar and Stellar Astrophysics · Physics 2017-02-08 Donguk Song , Jongchul Chae , Vasyl Yurchyshyn , Eun-Kyung Lim , Kyung-Suk Cho , Heesu Yang , Kyuhyoun Cho , Hannah Kwak

Downflows at supersonic speeds have been observed in the transition region (TR) above sunspots for more than three decades. These downflows are often seen in different TR spectral lines above sunspots. We have performed a statistical…

Solar and Stellar Astrophysics · Physics 2018-06-27 Tanmoy Samanta , Hui Tian , Debi Prasad Choudhary

The InfraRed Imaging Spectrograph (IRIS) is a first-light instrument for the Thirty Meter Telescope (TMT). It combines a diffraction limited imager and an integral field spectrograph. This paper focuses on the electrical system of IRIS.…

Instrumentation and Methods for Astrophysics · Physics 2018-08-24 A. C. Trapp , James Larkin , Ken Magnone , Timothee Greffe , Tim Hardy , Jennifer Dunn , Eric Chisholm , Chris Johnson , Ryuji Suzuki

The Mg II h&k lines are the prime chromospheric diagnostics of NASA's Interface Region Imaging Spectrograph (IRIS). In the previous papers of this series we used a realistic three-dimensional radiative magnetohydrodynamics model to…

Solar and Stellar Astrophysics · Physics 2013-11-21 Tiago M. D. Pereira , Jorrit Leenaarts , Bart De Pontieu , Mats Carlsson , Han Uitenbroek

The Solar Optical Telescope (SOT) aboard HINODE successfully and continuously observed a formation process of a light bridge in a matured sunspot of the NOAA active region 10923 for several days with high spatial resolution. During its…

(Abridged) Aims: In this paper, we seek to establish the suitability of imaging spectroscopy performed in the Ca II 854.2 nm line as a means to investigate the solar chromosphere at high resolution. Methods: We utilize monochromatic images…

CAIRNS (Cluster And Infall Region Nearby Survey) is a spectroscopic survey of the infall regions surrounding nine nearby rich clusters of galaxies. In Paper I, we used redshifts within $\sim 10\Mpc$ of the centers of the clusters to…

Astrophysics · Physics 2008-11-26 K. Rines , M. J. Geller , A. Diaferio , M. J. Kurtz , T. H. Jarrett

Observations of a relation between continuum intensity and magnetic field strength in sunspots have been made during nearly five decades. This work presents full-Stokes measurements of the full-split (g = 3) line Fe I 1564.85 nm with…

Solar and Stellar Astrophysics · Physics 2017-12-20 Michal Sobotka , Reza Rezaei
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