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Related papers: A solar-cycle study of coronal rotation: large var…

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Available helioseismic data now span almost the entire solar activity cycle 23 making it possible to study solar-cycle related changes of the solar rotation rate in detail. In this paper we study how the solar rotation rate, in particular,…

Astrophysics · Physics 2009-11-13 H. M. Antia , Sarbani Basu , S. M. Chitre

Coronal heating is a big question for modern astronomy. Daily measurement of 985 solar spectral irradiances (SSIs) at the spectral intervals 1-39 nm and 116-2416 nm during March 1 2003 to October 28 2017 is utilized to investigate…

Solar and Stellar Astrophysics · Physics 2019-04-24 KJ Li , JC Xu , ZQ Yin , W Feng

The Sun is a highly dynamic environment that exhibits dynamic behavior on many different timescales. In particular, coronal holes exhibit temporal and spatial variability. Signatures of these coronal dynamics are inherited by the coronal…

Using the Solar Optical Observing Network (SOON) sunspot-group data for the period 1985-2010, the variations in the annual mean equatorial-rotation rates of the sunspot groups are determined and compared with the known variations in the…

Solar and Stellar Astrophysics · Physics 2013-07-29 J. Javaraiah

Temporal variation of the solar coronal rotation appears to be very complex and its relevances to the eleven-year solar activity cycle are still unclear. Using the modified coronal index for the time interval from 1939 January 1 to 2019 May…

Solar and Stellar Astrophysics · Physics 2020-01-08 L. H. Deng , X. J. Zhang , H. Deng , Y. Mei , F. Wang

We investigate the characteristics and the sources of the slow (< 450 km/s) solar wind during the four years (2006-2009) of low solar activity between Solar Cycles 23 and 24. We use a comprehensive set of in-situ observations in the…

Solar and Stellar Astrophysics · Physics 2016-10-05 E. K. J. Kilpua , M. S. Madjarska , N. Karna , T. Wiegelmann , C. Farrugia , W. Yu , K. Andreeova

Understanding the global rotational profile of the solar atmosphere and its variation is fundamental to uncovering a comprehensive understanding of the dynamics of the solar magnetic field and the extent of coupling between different layers…

The strength and morphology of the Sun's magnetic field evolves significantly during the solar cycle, with the overall polarity of the Sun's magnetic field reversing during the maximum of solar activity. Long-term changes are also observed…

Solar and Stellar Astrophysics · Physics 2023-11-01 Adam J. Finley , Allan Sacha Brun

In-situ measurements by several spacecraft have revealed that the solar wind is frequently perturbed by transient structures (magnetic folds, jets, waves, flux-ropes) that propagate rapidly away from the Sun over large distances. Parker…

Solar and Stellar Astrophysics · Physics 2021-09-15 R. F. Pinto , N. Poirier , A. P. Rouillard , A. Kouloumvakos , L. Griton , N. Fargette , R. Kieokaew , B. Lavraud , A. S. Brun

Characterising the large-scale structure and plasma properties of the inner corona is crucial to understand the source and subsequent expansion of the solar wind and related space weather effects. Here we apply a new coronal rotational…

Solar and Stellar Astrophysics · Physics 2020-04-22 Huw Morgan , Anthony C. Cook

Rotation is a significant characteristic of the Sun and other stars, and it plays an important role in understanding their dynamo actions and magnetic activities. In this study, the rotation of the solar chromospheric activity is…

Solar and Stellar Astrophysics · Physics 2020-10-22 Jing-Chen Xu , Peng-Xin Gao , Xiang-Jun Shi

We measure differential rotation and meridional flow in the Sun's surface shear layer by tracking the motions of the magnetic network seen in magnetograms from SOHO/MDI and SDO/HMI over solar cycles 23, 24, and the start of 25 (1996-2022).…

Solar and Stellar Astrophysics · Physics 2022-12-22 David H. Hathaway , Lisa A. Upton , Sushant S. Mahajan

The differential rotation of the solar corona for the period 1976-2004 was studied as a function of the distance from the center of the Sun. For this study, we developed a method using the coronal magnetic field as a tracer. The field in a…

Solar and Stellar Astrophysics · Physics 2018-09-19 O. G. Badalyan , V. N. Obridko

The understanding of the solar magnetic coronal structure is tightly linked to the shape of open field regions, specifically coronal holes. A dynamically evolving coronal hole coincides with the local restructuring of open to closed…

An empirical model for forecasting solar wind speed related geomagnetic events is presented here. The model is based on the estimated location and size of solar coronal holes. This method differs from models that are based on photospheric…

Astrophysics · Physics 2008-11-26 S. Robbins , C. J. Henney , J. W. Harvey

This paper examines long-term temporal and spatial fluctuations in the solar rotation (more than four solar cycles) by investigating radio emission escapes from various layers of the solar atmosphere during the years 1967-2010. The flux…

Solar and Stellar Astrophysics · Physics 2021-07-06 Vivek Kumar Singh , Satish Chandra , Sanish Thomas , Som Kumar Sharma , Hari Om Vats

The aim of this paper is to study the latitudinal variation in the solar rotation in soft X-ray corona. The time series bins are formed on different latitude regions of the solar full disk (SFD) images that extend from 80 degree South to 80…

Solar and Stellar Astrophysics · Physics 2015-05-18 Satish Chandra , Hari Om Vats , K. N. Iyer

In the present work we study evolution of magnetic helicity in the solar corona. We compare the rate of change of a quantity related to the magnetic helicity in the corona to the flux of magnetic helicity through the photosphere and find…

Solar and Stellar Astrophysics · Physics 2021-06-29 A. Malanushenko , M. H. Yusuf , D. W. Longcope

Because of its distinctive compositional properties and variability, low-speed ($\lesssim 450$ km s$^{-1}$) solar wind is widely believed to originate from coronal streamers, unlike high-speed wind, which comes from coronal holes. An…

Solar and Stellar Astrophysics · Physics 2021-04-16 Y. -M. Wang , Y. -K. Ko

The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995-99. We find alternating latitudinal bands of faster…

Astrophysics · Physics 2009-10-31 H. M. Antia , Sarbani Basu
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