English
Related papers

Related papers: Uncertainty quantification in sunspot counts

200 papers

Some studies have shown that our knowledge on solar activity in the years 1640, 1652, and 1741 can be improved. In this contribution, we revise the annual group sunspot numbers for these years from original observations. For the years 1640,…

Solar and Stellar Astrophysics · Physics 2015-06-16 J. M. Vaquero , R. M. Trigo

Solar magnetic activity is expressed via variations of sunspots and active regions varying on different timescales. The most accepted is an 11-year period supposedly induced by the electromagnetic solar dynamo mechanism. There are also some…

Solar and Stellar Astrophysics · Physics 2023-01-19 Valentina V. Zharkova , Irina Vasilieva , Simon Shepherd , Elena Popova

This paper designs a statistical quantification towards the intermittent power uncertainty in power systems. A negative-exponential forecast uncertainty function is constructed to represent the relationship between the statistics of…

Systems and Control · Computer Science 2017-07-13 Zongjie Wang , Zhizhong Guo

We propose a modification to the standard statistical treatment of the detection cross-section uncertainties in the analysis of solar neutrino data. We argue that the uncertainties of the energy-averaged cross sections of the different…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. V. Garzelli , C. Giunti

Samuel Heinrich Schwabe made 8486 drawings of the solar disk with sunspots in the period from November 5, 1825 to December 29, 1867. We have measured sunspot sizes and heliographic positions on digitized images of these drawings. A total of…

Solar and Stellar Astrophysics · Physics 2015-06-16 R. Arlt , R. Leussu , N. Giese , K. Mursula , I. G. Usoskin

Sunspot catalogs are very useful for studying the solar activity of the recent past. In this context, a catalog covering more than three solar cycles made by the astronomers of the Madrid Astronomical Observatory in Spain (nowadays, the…

Solar and Stellar Astrophysics · Physics 2023-01-06 A. J. P. Aparicio , L. Lefèvre , M. C. Gallego , J. M. Vaquero , F. Clette , N. Bravo-Paredes , P. Galaviz , M. L. Bautista

It is well known that the observed amplitude of solar oscillations is lower in sunspots than in quiet regions of the Sun. We show that this local reduction in oscillation amplitudes combined with the phase-speed filtering procedure in…

Astrophysics · Physics 2009-11-11 S. P. Rajaguru , A. C. Birch , T. L. Duvall , M. J. Thompson , J. Zhao

Here we study the prediction of even and odd numbered sunspot cycles separately, thereby taking into account the Hale cyclicity of solar magnetism. We first show that the temporal evolution and shape of all sunspot cycles are extremely well…

Solar and Stellar Astrophysics · Physics 2023-09-11 Timo Asikainen , Jani Mantere

In September 1777, Ru{\dj}er Bo\v{s}kovi\'c observed sunspots for six days. Based on these measurements, he used his own methods to calculate the elements of the solar rotation, the longitude of the node, the inclination of the solar…

Solar and Stellar Astrophysics · Physics 2022-03-07 Mirko Husak , Roman Brajša , Dragan Špoljarić

Solar variability occurs over a broad range of spatial and temporal scales, from the Sun's brightening over its lifetime to the fluctuations commonly associated with magnetic activity over minutes to years. The latter activity includes most…

Solar and Stellar Astrophysics · Physics 2021-11-24 Valentina Penza , Francesco Berrilli , Luca Bertello , Matteo Cantoresi , Serena Criscuoli

The importance of the periodicity in sunspot appearance was well recognized by the mid of 19th century. Several observatories around the globe have made the record of sunspots in the form of drawings and preserved them safely for posterity.…

Solar and Stellar Astrophysics · Physics 2020-01-10 Ravindra B. , Kumaravel Pichamani , Selvendran R. , Joyce Samuel , Praveen Kumar , Nancy Jassoria , Navneeth R. S

Solar radio bursts (SRBs) are the signatures of various phenomena that happen in the solar corona and interplanetary medium (IPM). In this article, we have studied the occurrence of Type III bursts and their association with the Sunspot…

Solar and Stellar Astrophysics · Physics 2021-01-19 Theogene Ndacyayisenga , Jean Uwamahoro , K. Sasikumar Raja , Christian Monstein

The composite geometry and spectral anisotropy of the solar wind turbulence are very important topics in the investigations of solar wind. In this work, we use the magnetic field and plasma data from Wind spacecraft measured during 1995…

Space Physics · Physics 2025-05-20 Zhan Fa , H. -Q. He

We study the latitudinal distribution of sunspots observed from 1874 to 2009 using the center-of-latitude (COL). We calculate COL by taking the area-weighted mean latitude of sunspots for each calendar month. We then form the latitudinal…

Solar and Stellar Astrophysics · Physics 2015-05-30 Heon-Young Chang

In recent years solar oscillations have been studied in great detail, both observationally and theoretically; so, perhaps, the Sun currently is the best understood pulsating star. The observational studies include long, almost uninterrupted…

Solar and Stellar Astrophysics · Physics 2010-02-01 A. G. Kosovichev

Sunspot engravings and measurements in 1660-1676 are analyzed to retrieve sunspot area and heliocoordinates. Based on these data, we revise the Hoyt and Schatten (The role of the sun in climate change, 1997) hypothesis of long-lived…

Solar and Stellar Astrophysics · Physics 2025-02-25 Nadezhda Zolotova , Mikhail Vokhmyanin

Our prior research found that a $90^{\circ}$ configuration of two planetary groups were temporally associated with significant changes in global electromagnetic standing waves (Schumann resonances) during and after the three $90^{\circ}$…

Solar and Stellar Astrophysics · Physics 2026-01-09 Jeff A Hansen , Shaun David Brocus Fell

The ability to predict the future behavior of solar activity has become of extreme importance due to its effect on the near Earth environment. Predictions of both the amplitude and timing of the next solar cycle will assist in estimating…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. Ajabshirizadeh , N. Masoumzadeh Jouzdani , S. Abbassi

Aims. In this paper, we aim to study the time dependence of sunspot group areas in a large sample composed of various databases spanning over 130 years, used state-of-the-art statistical methods. Methods. For a carefully selected but…

Solar and Stellar Astrophysics · Physics 2021-09-08 Emese Forgács-Dajka , László Dobos , István Ballai

Based on the Chinese historical sunspots drawings, a data set consisting of the scanned images and all their digitized parameters from 1925 to 2015 have been constructed. In this paper, we briefly describe the developmental history of…

‹ Prev 1 8 9 10 Next ›