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Related papers: Microwave response to sunspot oscillations

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Three-minute oscillations over sunspot's umbra in AR 11131 were observed simultaneously in UV/EUV emission by SDO/AIA and in radio emission by Nobeyama Radioheliograph (NoRH). We use 24-hours series of SDO and 8-hours series of NoRH…

Solar and Stellar Astrophysics · Physics 2015-05-30 V. E. Reznikova , K. Shibasaki , R. A. Sych , V. M. Nakariakov

Sunspots host various oscillations and wave phenomena like umbral flashes, umbral oscillations, running penumbral waves, and coronal waves. All fan loops rooted in sunspot umbra constantly show a 3-min period propagating slow…

Solar and Stellar Astrophysics · Physics 2023-08-22 Ananya Rawat , Girjesh R. Gupta

The sunspot-associated sources at the frequency of 17 GHz give information on plasma parameters in the regions of magnetic field about B=2000 G at the level of the chromosphere-corona transition region. The observations of short period…

Solar and Stellar Astrophysics · Physics 2015-03-19 Vladimir E. Abramov-Maximov , George B. Gelfreikh , Kiyoto Shibasaki

We present results from the investigation of 5-min umbral oscillations in a single-polarity sunspot of active region NOAA 12132. The spectra of TiO, H$\alpha$, and 304 \AA{} are used for corresponding atmospheric heights from the…

Solar and Stellar Astrophysics · Physics 2018-01-10 T. G. Priya , Wenda Cao , Jiangtao Su , Jie Chen , Xinjie Mao , Yuanyong Deng , Robert Erdélyi

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 a study of wave processes occurring in solar active region NOAA 11131 on 2010 December 10, captured by the Solar Dynamics Observatory in the 1600A, 304A, and 171A channels. For spectral analysis we employed pixelised wavelet…

Solar and Stellar Astrophysics · Physics 2021-01-20 Robert Sych , David B. Jess , Jiangtao Su

We analyse 3-min oscillations of microwave and EUV emission generated at different heights of a sunspot atmosphere, studying the amplitude and frequency modulation of the oscillations, and its relationship with the variation of the spatial…

Solar and Stellar Astrophysics · Physics 2015-05-30 R. Sych , T. V. Zaqarashvili , V. M. Nakariakov , S. A. Anfinogentov , K. Shibasaki , Y. Yan

We infer the depth of the internal sources giving rise to three-minute umbral oscillations. Recent observations of ripple-like velocity patterns of umbral oscillations supported the notion that there exist internal sources exciting the…

Solar and Stellar Astrophysics · Physics 2020-04-15 Kyuhyoun Cho , Jongchul Chae

We present a study of wave processes in the sunspot region NOAA 12670 on 2017 August 10 observed by the Goode Solar Telescope in the TiO 7057 A and Ha 6563 A spectral lines. To study the distribution of power oscillations and their…

Solar and Stellar Astrophysics · Physics 2020-01-15 Robert Sych , Yuzef Zhugzhda , Xiaoli Yan

Data analysis of sunspot oscillation based on 6-hr SDO run of observation showed that low frequency (0.2 < ! < 1 mHz) oscillations are local similar to three and five minute oscillations. The oscillations in the sunspot are concentrated in…

Solar and Stellar Astrophysics · Physics 2018-09-19 Y. Zhugzhda , R. Sych

Three- and five-minute oscillations of sunspots have different spatial distributions in the solar atmospheric layers. The spatial distributions are crucial to reveal the physical origin of sunspot oscillations and to investigate their…

Solar and Stellar Astrophysics · Physics 2020-02-05 Zhengkai Wang , Song Feng , Linhua Deng , Yao Meng

The high spatial and time resolution data obtained with SDO/AIA for the sunspot in active region NOAA 11131 on 08 December 2010 were analysed with the time-distance plot technique and the pixelised wavelet filtering method. Oscillations in…

Solar and Stellar Astrophysics · Physics 2014-09-17 R. Sych , V. M. Nakariakov

We use high spatial and temporal resolution observations, simultaneously obtained with the New Vacuum Solar Telescope and Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, to investigate the high-frequency…

Solar and Stellar Astrophysics · Physics 2018-03-28 Feng Wang , Hui Deng , Bo Li , Song Feng , Xianyong Bai , Linhua Deng , Yunfei Yang , Zhike Xue , Rui Wang

A phenomenological relationship between oscillations in a sunspot and quasi-periodic pulsations in flaring energy releases at an active region above the sunspot, is established. The analysis of the microwave emission recorded by the…

Solar and Stellar Astrophysics · Physics 2015-05-19 R. Sych , V. M. Nakariakov , M. Karlicky , S. Anfinogentov

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

We present observations of persistent oscillations of some bright features in the upper-chromosphere/transition-region above sunspots taken by IRIS SJ 1400 {\AA} and upward propagating quasi-periodic disturbances along coronal loops rooted…

Solar and Stellar Astrophysics · Physics 2018-03-21 Zhenyong Hou , Zhenghua Huang , Lidong Xia , Bo Li , Hui Fu

Three-minute oscillations are a common phenomenon in the solar chromosphere above a sunspot. Oscillations can be affected by the energy release process related to solar flares. In this paper, we report on an enhanced oscillation in flare…

Solar and Stellar Astrophysics · Physics 2023-11-30 Ya Wang , Lyndsay Fletcher , Sargam Mulay , Haisheng Ji , Wenda Cao

3-minute oscillations in the chromosphere are attributed to both slow magnetoacoustic waves propagating from the photosphere, and to oscillations generated within the chromosphere itself at its natural frequency as a response to a…

Solar and Stellar Astrophysics · Physics 2020-11-23 Laurel Farris , R. T. James McAteer

Regular observations of active processes in the solar atmosphere have been started using the first stage of the multiwave Siberian Radioheliograph (SRH), a T-shaped 48-antenna array with a 4-8 GHz operating frequency range and a 10 MHz…

Radio observations offer a dust-independent probe of star formation and active galactic nucleus (AGN) activity, but sufficiently deep data are required to access the crossover luminosity between these processes at high redshift ($z>4.5$).…

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