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Image super-resolution has been an important subject in image processing and recognition. Here, we present an attention-aided convolutional neural network (CNN) for solar image super-resolution. Our method, named SolarCNN, aims to enhance…

Solar and Stellar Astrophysics · Physics 2024-03-28 Chunhui Xu , Jason T. L. Wang , Haimin Wang , Haodi Jiang , Qin Li , Yasser Abduallah , Yan Xu

The presence of intense magnetic fields in and around sunspots is expected to modify the solar structure and oscillation frequencies. Applying the ring diagram technique to data from the Michelson Doppler Imager (MDI) on board the Solar and…

Astrophysics · Physics 2009-11-07 S. P. Rajaguru , Sarbani Basu , H. M. Antia

A number of recent investigations have revealed that transverse waves are ubiquitous in the solar chromosphere. The vast majority of these have been reported in limb spicules and active region fibrils. We investigate long-lived, quiet Sun,…

Solar and Stellar Astrophysics · Physics 2015-06-04 D. Kuridze , R. J. Morton , R. Erdélyi , G. D. Dorrian , M. Mathioudakis , D. B. Jess , F. P. Keenan

Macrospicules (MS) are localised small-scale jet-like phenomena in the solar atmosphere, which have the potential to transport considerable amount of momentum and energy from the lower solar atmospheric regions to the Transition Region and…

Solar and Stellar Astrophysics · Physics 2017-02-01 T. S. Kiss , N. Gyenge , R. Erdelyi

Supergranules in the quiet Sun are outlined by a web-like structure of enhanced magnetic field strength, the so-called magnetic network. We aim to map the magnetic network field around the average supergranule near disk center. We use…

Solar and Stellar Astrophysics · Physics 2015-07-08 J. Langfellner , L. Gizon , A. C. Birch

Using data from the Global Oscillation Network Group (GONG) covering the period from 1995 to 1998, we study the change with solar activity in solar f-mode frequencies. The results are compared with similar changes detected from the…

Astrophysics · Physics 2015-06-24 H. M. Antia , Sarbani Basu , J. Pintar , B. Pohl

We develop a microfluidic platform for the long-term cultivation and observation of both THP-1 cells under different physiological conditions. First, we determine optimal seeding conditions and microwell geometry. Next, we observe changes…

Biological Physics · Physics 2023-10-20 Richard Lee Lai

We studied long duration flare observed with Nobeyama Radioheliograph at frequencies 17 and 34 GHz and with Ramaty High Energy Solar Spectroscopic Imager at 25-50 keV. We found that microwave and hard X-ray emission variation contain…

Solar and Stellar Astrophysics · Physics 2011-10-07 Veronika Reznikova , Kiyoto Shibasaki

Helioseismic observations have detected small temporal variations of the rotation rate below the solar surface corresponding to the so-called `torsional oscillations' known from Doppler measurements of the surface. These appear as bands of…

Context. Solar Rossby waves (r modes) have recently been discovered in the near-surface horizontal flow field using the techniques of granulation-tracking and ring-diagram analysis applied to six years of SDO/HMI data. Aims. Here we apply…

Solar and Stellar Astrophysics · Physics 2019-06-05 Zhi-Chao Liang , Laurent Gizon , Aaron C. Birch , Thomas L. Duvall

I analyse the maps recording the travel-time shifts caused by averaged plasma anomalies under an "average supergranule", constructed by means of statistical averaging over 5582 individual supergranules with large divergence signals detected…

Solar and Stellar Astrophysics · Physics 2015-06-11 Michal Svanda

The solar magnetism is no more considered as a purely superficial phenomenon. The SoHO community has shown that the length of the solar cycle depends on the transition region between radiation and convection. Nevertheless, the internal…

We present a comparative seismic study of conditions around and beneath isolated sunspots. Using the European Grid of Solar Observations' Solar Feature Catalogue of sunspots derived from SOHO/MDI continuum and magnetogram data, 1996-2005,…

Astrophysics · Physics 2009-11-13 S. Zharkov , C. Nicholas , M. J. Thompson

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 studied the low-frequency $\lesssim 0.5\;$h$^{-1}$ (long-period $\gtrsim 2\;$h) oscillations of active regions (ARs). The investigation is based on an analysis of a time series built from Solar Dynamics Observatory/Helioseismic and…

Solar and Stellar Astrophysics · Physics 2022-03-22 G. Dumbadze , B. M. Shergelashvili , S. Poedts , T. V. Zaqarashvili , M. Khodachenko , P. De Causmaecker

In the present work we show robust indications of the existence of g modes in the Sun using 10 years of GOLF data. The present analysis is based on the exploitation of the collective properties of the predicted low-frequency (25 to 140…

In this paper, the physical conditions within the inhomogeneous solar atmosphere have been reconstructed by means of solving the inverse problem of Non Local Thermodynamic Equilibrium (NLTE) radiative transfer. The profiles of…

Astrophysics · Physics 2008-11-26 M. I. Stodilka , S. Z. Malynych

We have analyzed available full-disc data from the Michelson Doppler Imager (MDI) on board SoHO using the "ring diagram" technique to determine the behavior of solar meridional flows over solar cycle 23 in the outer 2% of the solar radius.…

Solar and Stellar Astrophysics · Physics 2015-05-19 Sarbani Basu , H. M. Antia

Convection, differential rotation, and meridional circulation of solar plasma are studied based on helioseismic data covering the period from May 2010 to August 2024, significantly prolonged compared to that previously considered. Depth…

Solar and Stellar Astrophysics · Physics 2025-04-22 A. V. Getling , A. G. Kosovichev

Helioseismic and magnetohydrodynamic waves are abundant in and above sunspots. Through cross-correlating oscillation signals in the photosphere observed by the SDO/HMI, we reconstruct how waves propagate away from virtual wave sources…

Solar and Stellar Astrophysics · Physics 2015-08-19 Junwei Zhao , Ruizhu Chen , Thomas Hartlep , Alexander G. Kosovichev