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Related papers: Statistical analysis of solar H-alpha flares

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A statistical analysis of dataset of H-alpha, soft X-ray (SXR) and Hard X-ray (HXR) flares comprising almost 318, 401 and 1920 single events respectively that occurred during the period of October-November 2003 is presented. On the basis of…

Solar and Stellar Astrophysics · Physics 2009-09-30 Navin Chandra Joshi , Neeraj Singh Bankoti , Seema Pande , Bimal Pande , Kavita Pandey

In this paper, we have made a statistical analysis of solar H$\alpha$ flares that occurred during the period 1996 to 2005 to investigate their spatial distribution with respect to northern and southern hemispheres of the Sun. The analysis…

Astrophysics · Physics 2007-08-16 Bhuwan Joshi , P. Pant , P. K. Manoharan , Kavita Pandey

Aims. In this paper, we investigate the temporal evolution and north-south (N-S) asymmetry in the occurrence of solar flares during cycle 21, 22, and 23, and compare the results with traditional solar activity indices. Methods. The flare…

Solar and Stellar Astrophysics · Physics 2017-05-08 Bhuwan Joshi , R. Bhattacharyya , K. K. Pandey , Upendra Kushwaha , Yong-Jae Moon

This paper presents a statistical analysis of Soft X-ray (SXR) flares during the period January 1976 to December 2007 covering solar cycles (SCs) 21, 22, and 23. We have analysed north-south (N-S) and east-west (E-W) asymmetry of SXR at low…

Solar and Stellar Astrophysics · Physics 2015-05-13 Navin Chandra Joshi , Neeraj Singh Bankoti , Seema Pande , Bimal Pande , Kavita Pandey

We analyze the occurrence frequency distributions of peak fluxes $P$, total fluxes $E$, and durations $T$ of solar flares over the last three solar cycles (during 1980--2010) from hard X-ray data of HXRBS/SMM, BATSE/CGRO, and RHESSI. From…

Solar and Stellar Astrophysics · Physics 2012-01-13 Markus J. Aschwanden

Although the energetic phenomena of the Sun (flares, coronal mass injections etc.) exhibit intermittent stochastic behavior in their rate of occurrence, they are well correlated to the variations of the solar cycle. In this work we study…

Solar and Stellar Astrophysics · Physics 2010-09-23 E. Gini , J. Polygiannakis , A. Hillaris , P. Preka-Papadema , X. Moussas

The flare activity and the ultraviolet emission of the sun during its 24-th cycle are analysed. As compared to cycles 21-23, where the most powerful flares were observed during the decay phase, in cycle 24 the greatest number of powerful…

Solar and Stellar Astrophysics · Physics 2017-11-29 E. A. Bruevich , G. V. Yakunina

Solar flares stronger than X10 (S-flares, >X10) are the highest class flares which significantly impact on the Sun's evolution and space weather. Based on observations of Geostationary Orbiting Environmental Satellites (GOES) at soft X-ray…

Solar and Stellar Astrophysics · Physics 2025-01-10 Baolin Tan , Yin Zhang , Jing Huang , Kaifan Ji

Aims. The H-alpha emission of solar flare kernels and associated hard X-ray (HXR) emission often show similar time variations but their light curves are shifted in time by energy transfer mechanisms. We searched for fast radiative response…

Solar and Stellar Astrophysics · Physics 2015-05-30 K. Radziszewski , P. Rudawy , K. J. H. Phillips

We study the decay phase of solar flares in several spectral bands using a method based on that successfully applied to white light flares observed on an M4 dwarf. We selected and processed 102 events detected in the Sun-as-a-star flux…

Solar and Stellar Astrophysics · Physics 2021-02-10 Larisa K. Kashapova , Anne-Marie Broomhall , Alena I. Larionova , Elena G. Kupriyanova , Ilya D. Motyk

Stellar flares sometimes show red/blue asymmetries of H$\alpha$ line, which can indicate chromospheric dynamics and prominence activations. However, the origin of asymmetries is not completely understood. For a deeper understanding of…

Solar and Stellar Astrophysics · Physics 2022-07-27 Kosuke Namekata , Kiyoshi Ichimoto , Takako T. Ishii , Kazunari Shibata

To understand the conditions that produce white-light (WL) enhancements in solar flares, a statistical analysis of visible continuum data as observed by Hinode/Solar Optical Telescope (SOT) was performed. In this study, approximately 100…

Solar and Stellar Astrophysics · Physics 2017-12-20 Kyoko Watanabe , Jun Kitagawa , Satoshi Masuda

The spot evolution on the Sun and solar-type stars is important for understanding the nature of consequential flaring activity. This study statistically investigates the variance of flare occurrence rate through the time evolution of spots…

Solar and Stellar Astrophysics · Physics 2025-05-23 Takato Tokuno , Kosuke Namekata , Hiroyuki Maehara , Shin Toriumi

The light curves of solar flares in the impulsive phase are complex in general, indicating that multiple physical processes are involved in. With the GOES (Geostationary Operational Environmental Satellite) observations, we find that there…

Solar and Stellar Astrophysics · Physics 2015-06-16 HAN , Fei-ran , LIU , Si-ming

Here we present the results of the study of the north-south (N-S) distribution and asymmetry of GOES soft X-ray (SXR) flares during solar cycle 24. The period of study includes ascending, maximum and descending phases of the cycle. During…

Solar and Stellar Astrophysics · Physics 2020-07-15 Anita Joshi , Ramesh Chandra

In this paper, we investigate the spatial distribution of solar flares in the northern and southern hemisphere of the Sun that occurred during the period 1996 to 2003. This period of investigation includes the ascending phase, the maximum…

Astrophysics · Physics 2009-11-11 Bhuwan Joshi , P. Pant , P. K. Manoharan

Sympathetic solar flares are eruptions that occur nearby in space and time, driven by an apparent interaction between the active regions in which they are triggered. Their statistical existence on the Sun has yet to be firmly established.…

Solar and Stellar Astrophysics · Physics 2025-02-05 Louis-Simon Guité , Antoine Strugarek , Paul Charbonneau

Using the short-cadence data (1-min interval) of the Kepler space telescope, we conducted a statistical analysis for the characteristic time of stellar flares on Sun-like stars (SLS). Akin to solar flares, stellar flares show rise and decay…

Solar and Stellar Astrophysics · Physics 2021-06-16 Y. Yan , H. He , C. Li , A. Esamdin , B. L. Tan , L. Y. Zhang , H. Wang

The duration of activity growths in solar cycles is on average shorter than the duration of its declines. This asymmetry can result from fluctuations in dynamo parameters. A solar dynamo model with fluctuations in the $\alpha$-effect shows…

Solar and Stellar Astrophysics · Physics 2018-11-07 Leonid Kitchatinov , Alexander Nepomnyashchikh

Introducing thresholds to analyze time series of emission from the Sun enables a new and simple definition of solar flare events, and their interoccurrence times. Rescaling time by the rate of events, the waiting and quiet time…

Statistical Mechanics · Physics 2007-05-23 Marco Baiesi , Maya Paczuski , Attilio L. Stella
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