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Related papers: Rapid Fluctuations in the Lower Solar Atmosphere

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We study Hinode/SOT-FG observations of intensity fluctuations in Ca II H-line and G-band image sequences and their relation to simultaneous and co-spatial magnetic field measurements. We explore the G-band and H-line intensity oscillation…

Solar and Stellar Astrophysics · Physics 2015-06-05 J. K. Lawrence , A. C. Cadavid

Aims. With the Solar Optical Telescope on Hinode, we investigate the basic properties of high-degree solar oscillations observed at two levels in the solar atmosphere, in the G-band (formed in the photosphere) and in the Ca II H line…

Astrophysics · Physics 2009-11-13 U. Mitra-Kraev , A. G. Kosovichev , T. Sekii

We investigate the statistics of the intensity distributions as function of the wavelength for Ca II H and the CA II IR line at 854.2 nm to estimate the energy content. We derived the intensity variations at different heights of the solar…

Solar and Stellar Astrophysics · Physics 2013-03-14 C. Beck , R. Rezaei , K. G. Puschmann

We study the acoustic properties of the solar chromosphere in the high-frequency regime using a time sequence of velocity measurements in the chromospheric Ca II 854.2 nm line taken with the Interferometric Bidimensional Spectrometer…

Astrophysics · Physics 2010-11-11 K. P. Reardon , F. Lepreti , V. Carbone , A. Vecchio

The solar wind is highly turbulent, and intermittency effects are observed for fluctuations within the inertial range. By analyzing magnetic field spectra and fourth-order moments, we perform a comparative study of turbulence and…

Space Physics · Physics 2025-02-11 Shiladittya Mondal , Supratik Banerjee , Luca Sorriso-Valvo

Exploiting high-resolution observations made by the Solar Optical Telescope onboard Hinode, we investigate the spatial distribution of power spectral density of oscillatory signal in and around NOAA active region 10935. The G-band data show…

In the present paper, we use Si IV 1393.755 \AA\ spectral line observed by the Interface Region Imaging Spectrograph (IRIS) in the quiet-Sun to determine physical nature of the solar transition region (TR) oscillations. We analyze the…

Solar and Stellar Astrophysics · Physics 2022-10-12 Kartika Sangal , A. K. Srivastava , P. Kayshap , T. J Wang , J. J. González-Avilés , Abhinav Prasad

Plasma turbulence cascading from MHD to kinetic scales in the heliospheric plasma is believed to play a key role in coronal heating and fast solar wind acceleration, but the properties of the turbulence remain poorly constrained by…

Solar and Stellar Astrophysics · Physics 2026-02-03 Eduard P. Kontar , A. Gordon Emslie , Daniel L. Clarkson , Alexander Pitna

Fluctuations and structure across a wide range of spatial and temporal scales are frequently studied in the solar wind. The properties of the low-frequency fluctuations are of relevance to turbulent energy injection into the plasma and the…

Solar and Stellar Astrophysics · Physics 2026-01-06 Jiaming Wang , Francesco Pecora , Rohit Chhiber , Sohom Roy , William H. Matthaeus

We find evidence for the first observation of the parametric decay instability (PDI) in the lower solar atmosphere. Specifically, we find that the power spectrum of density fluctuations near the solar transition region resembles the power…

Solar and Stellar Astrophysics · Physics 2022-07-20 Michael Hahn , Xiangrong Fu , Daniel Wolf Savin

Solar wind fluctuations, such as magnetic field or velocity, show power law power spectra suggestive both of an inertial range of intermittent turbulence (with $\sim -5/3$ exponent) and at lower frequencies, of fluctuations of coronal…

Astrophysics · Physics 2009-11-13 R. M. Nicol , S. C. Chapman , R. O. Dendy

We study the space-time distributions of intensity fluctuations in 2 - 3 hour sequences of multi-spectral, high-resolution, high-cadence broad-band filtergram images (BFI) made by the SOT-FG system aboard the Hinode spacecraft. In the…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. K. Lawrence , A. C. Cadavid

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

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

Waves are thought to play a significant role in the heating of the solar atmosphere and the acceleration of the wind. Among the many types of waves observed in the Sun, the so-called p-modes with a 3 mHz frequency peak dominate the lower…

We present observational constraints on the solar chromospheric heating contribution from acoustic waves with frequencies between 5 and 50 mHz. We utilize observations from the Dunn Solar Telescope in New Mexico complemented with…

Solar and Stellar Astrophysics · Physics 2021-11-03 Momchil E. Molnar , Kevin P. Reardon , Steven R. Cranmer , Adam F. Kowalski , Yi Chai , Dale Gary

Parker Solar Probe measurements have recently shown that coherent fast magnetosonic and Alfv\'{e}n ion-cyclotron waves are abundant in the solar wind and can be accompanied by higher-frequency electrostatic fluctuations. In this letter we…

Solar and Stellar Astrophysics · Physics 2024-04-26 I. Y. Vasko , F. S. Mozer , T. Bowen , J. Verniero , X. An , A. V. Artemyev , J. W. Bonnell , J. Halekas , I. V. Kuzichev

Searches for small exoplanets around solar-type stars are limited by stellar physical variability. While chromospheric variability is well studied, observing, modeling. and understanding the much smaller fluctuations in photospheric…

Solar and Stellar Astrophysics · Physics 2024-07-03 Dainis Dravins , Hans-Günter Ludwig

Electric field measurements of the Time Domain Sampler (TDS) receiver, part of the Radio and Plasma Waves (RPW) instrument on board Solar Orbiter, often exhibit very intense broadband wave emissions at frequencies below 20~kHz in the…

Velocity oscillations in sunspot umbrae have been measured simultaneously in two spectral lines: the photospheric Silicon I 10827 A line and the chromospheric Helium I 10830 A multiplet. From the full Stokes inversion of temporal series of…

Astrophysics · Physics 2009-11-13 Rebecca Centeno , Manuel Collados , Javier Trujillo Bueno
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