English
Related papers

Related papers: Re-examining Sunspot Tilt Angle to Include Anti-Ha…

200 papers

We analyze both Kitt Peak magnetogram data and MDI continuum intensity sunspot data to search for the following solar toroidal band properties: width in latitude and the existence of a tipping instability (longitudinal m=1 mode) for any…

Astrophysics · Physics 2009-11-11 Aimee A. Norton , Peter A. Gilman

We study the asymmetric distribution of weak photospheric magnetic field values in the two hemispheres separately using synoptic maps from SDO/HMI, SOLIS/VSM and WSO during solar cycles 21-24. We calculate the weak-field asymmetry (shift)…

Solar and Stellar Astrophysics · Physics 2019-10-09 Tibebu Getachew , Ilpo Virtanen , Kalevi Mursula

Understanding the characteristics of the solar magnetic field is essential for interpreting solar activities and dynamo. In this research, we investigated the asymmetric distribution of the solar photospheric magnetic field values, using…

Solar and Stellar Astrophysics · Physics 2021-10-04 Jing-Chen Xu , Ke-Jun Li , Peng-Xin Gao

The Maunder Minimum (1645-1715 approximately) was a period of very low solar activity and a strong hemispheric asymmetry, with most of sunspots in the southern hemisphere. In this paper, two data sets of sunspot latitudes during the Maunder…

Solar and Stellar Astrophysics · Physics 2015-01-27 J. M. Vaquero , J. M. Nogales , F. Sánchez-Bajo

Using magnetic field maps acquired by the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory we measured rotation rates of 864 active and 322 ephemeral regions observed between 2010 and 2016. We found smaller magnetic…

Solar and Stellar Astrophysics · Physics 2020-11-25 Alexander S. Kutsenko

Solar wind electron velocity distributions at 1 au consist of a thermal "core" population and two suprathermal populations: "halo" and "strahl". The core and halo are quasi-isotropic, whereas the strahl typically travels radially outwards…

Several papers provide evidences that the most probable sites of flare onset are the regions of high horizontal magnetic field gradients in solar active regions. Besides the localization of flare producing areas the present work intends to…

Solar and Stellar Astrophysics · Physics 2016-10-21 M. B. Korsos , T. Baranyi , A. Ludmany

One of the intriguing mechanisms of the Sun is the formation of the bipolar magnetic regions (BMRs) in the solar convection zone which are observed as regions of concentrated magnetic fields of opposite polarity on photosphere. These BMRs…

Solar and Stellar Astrophysics · Physics 2025-12-19 Anu Sreedevi , Bibhuti Kumar Jha , Bidya Binay Karak , Dipankar Banerjee

The changing magnetic fields of the Sun are generated and maintained by a solar dynamo, the exact nature of which remains an unsolved fundamental problem in solar physics. Our objective in this paper is to investigate the role and impact of…

Solar and Stellar Astrophysics · Physics 2023-10-03 Kinfe Teweldebirhan , Mark Miesch , Sarah Gibson

This article presents a publicly available, multimodal, tiered magnetic polarity inversion lines (MPILs) dataset extracted from the Solar Dynamics Observatory's (SDO) Helioseismic and Magnetic Imager (HMI) Active Region Patches (SDO/HMI…

Solar and Stellar Astrophysics · Physics 2025-08-26 Ziba Khani , Anli Ji , Manolis K. Georgoulis , Berkay Aydin

The magnetic field inside the sunspot umbra, as observed by the Full-disk MagnetoGraph (FMG) onboard the Advanced Space based Solar Observatory (ASO-S), was found to be experiencing a weakening. To address this issue, we employed a method…

Solar and Stellar Astrophysics · Physics 2024-05-30 Haiqing Xu , Jiangtao Su , Suo Liu , Yuanyong Deng , Xianyong Bai , Jie Chen , Xiaofan Wang , Xiao Yang , Yongliang Song

We investigate the restructuring of the magnetic field in sunspots associated with two flares: the X6.5 flare on 6 December 2006 and the X2.2 flare on 15 February 2011. The observed changes were evaluated with respect to the so-called…

Solar and Stellar Astrophysics · Physics 2017-11-15 Olga Burtseva , Sanjay Gosain , Alexei A. Pevtsov

Based on the data from the Kodaikanal and Mount Wilson observatories, we investigate the relationships of the tilt angle of sunspot group (SG), including the mean tilt angle and the tilt-angle scatter, during the declining phase with the…

Solar and Stellar Astrophysics · Physics 2024-10-30 P. X. Gao , J. C. Xu

Context. The Sun shows an activity cycle that is caused by its varying global magnetic field. During a solar cycle, sunspots, i.e. extended regions of strong magnetic fields, occur in activity belts that are slowly migrating from middle to…

Solar and Stellar Astrophysics · Physics 2015-11-25 D. Utz , R. Muller , S. Thonhofer , A. Veronig , A. Hanslmeier , M. Bodnárová , M. Bárta , J. C. del Toro Iniesta

The distribution of magnetic fields of positive and negative polarities over the surface of the Sun was studied. Synoptic maps of the photospheric magnetic field (NSO Kitt Peak, 1978--2016) were used for the analysis. In the time-latitude…

Solar and Stellar Astrophysics · Physics 2022-06-20 E. S. Vernova , M. I. Tyasto , D. G. Baranov

The Sun shows a global magnetic field cycle traditionally best visible in the photosphere as a changing sunspot cycle featuring roughly an 11 year period. In addition we know that our host star also harbours small-scale magnetic fields…

Solar and Stellar Astrophysics · Physics 2017-12-20 D. Utz , R. Muller , T. Van Doorsselaere

Variations of the weak magnetic fields of the photosphere with periods of the order of the solar magnetic cycle were investigated. Synoptic maps of the photospheric magnetic field produced by NSO Kitt Peak for the period from 1978 to 2016…

Solar and Stellar Astrophysics · Physics 2023-07-18 E. S. Vernova , M. I. Tyasto , D. G. Baranov

We present a physical mechanism of formation of tilt angles of sunspots due to the process of formation of active regions below the solar photosphere. The contribution of Coriolis force factors on large-scale flows of super-granular…

Solar and Stellar Astrophysics · Physics 2019-05-22 K. M. Kuzanyan , N. Safiullin , N. Kleeorin , I. Rogachevskii , S. Porshnev

The 11-year cycle of solar activity follows Hale's law by reversing the magnetic polarity of leading and following sunspots in bipolar regions during the minima of activity. In the 1996-97 solar minimum, most solar activity emerged in…

Astrophysics · Physics 2009-10-31 E. E. Benevolenskaya , J. T. Hoeksema , A. G. Kosovichev , P. H. Scherrer
‹ Prev 1 3 4 5 6 7 10 Next ›