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Related papers: Uncertainties in the Sunspot Numbers: Estimation a…

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Observing and counting sunspots constitutes one of the longest-running scientific experiment, with first observations dating back to Galileo and the invention of the telescope around 1610. Today the sunspot number (SN) time series acts as a…

Solar and Stellar Astrophysics · Physics 2020-09-22 Sophie Mathieu , Véronique Delouille , Laure Lefèvre , Christian Ritter , Rainer von Sachs

The relative number of sunspots represents the longest evidence describing the level of solar activity. As such, its use goes beyond solar physics, e.g. towards climate research. The construction of a single representative series is a…

Solar and Stellar Astrophysics · Physics 2022-12-07 Michal Švanda , Martina Pavelková , Jiří Dvořák , Božena Solarová

Solar activity is an important driver of long-term climate trends and must be accounted for in climate models. Unfortunately, direct measurements of this quantity over long periods do not exist. The only observation related to solar…

Solar and Stellar Astrophysics · Physics 2023-01-12 Sophie Mathieu , Laure Lefèvre , Rainer von Sachs , Véronique Delouille , Christian Ritter , Frédéric Clette

The rise and fall in the number of sunspots have served as a lynchpin in many investigations on solar dynamics. Arising from magnetic disturbances in the sun, variations in sunspot numbers have helped define a solar cycle of around eleven…

Solar and Stellar Astrophysics · Physics 2023-06-27 Reynan L. Toledo , Reinabelle Reyes , Christopher C. Bernido

In most star formation history (SFH) measurements, the reported uncertainties are those due to effects whose sizes can be readily measured: Poisson noise, adopted distance and extinction, and binning choices in the solution itself. However,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Andrew E. Dolphin

Recent research has demonstrated that the number of sunspots per group ('active region') has been decreasing over the last two or three solar cycles and that the classical Relative Sunspot Number (SSN) no longer is a good representation of…

Solar and Stellar Astrophysics · Physics 2015-06-19 Leif Svalgaard

Sunspots are dark spots on the solar surface associated with strong magnetic fields. The number, area, and brightness of sunspots are supposed to reflect the intensity of the solar magnetic fields and are often used as proxies for their…

Solar and Stellar Astrophysics · Physics 2015-06-16 K. Georgieva , B. Kirov , Yu. A. Nagovitsyn

The torsional oscillation is a well established observational fact and there are theoretical attempts for its description but no final solution has yet been accepted. One of the possible candidates for its cause is the presence of sunspots…

Solar and Stellar Astrophysics · Physics 2014-01-13 J. Muraközy , A. Ludmány

Sunspot numbers are important tracers of historical solar activity. They are important in the prediction of oncoming solar maximum, in the design of lifetimes of space assets, and in assessing the extent of solar-radiation impact on the…

Solar and Stellar Astrophysics · Physics 2016-02-26 K. S. Balasubramaniam , T. W. Henry

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the…

Astrophysics · Physics 2009-11-05 J. M. Borrero

Correlations between planetary and stellar properties, particularly age, can provide insight on planetary formation and evolution processes. However, the underlying source of such trends can be unclear, and measurement uncertainties and…

Earth and Planetary Astrophysics · Physics 2022-03-30 Emily D. Safsten , Rebekah I. Dawson

Sunspots are areas of strong magnetic fields driven by a convective dynamo. Rudolf Wolf devised his Sunspot Number (SN) series to describe its variation with time. Most other solar phenomena vary in concert with SN, in particular the…

Instrumentation and Methods for Astrophysics · Physics 2025-05-15 Leif Svalgaard

The long-standing disparity between the sunspot number record and the Hoyt and Schatten (1998, H&S) Group Sunspot Number series was initially resolved by the Clette et al. (2014) revision of the sunspot number and the group number series.…

Solar and Stellar Astrophysics · Physics 2020-11-12 Leif Svalgaard

In 2015 the calculation of the International (Zurich) sunspot number was cancelled, and it was replaced by a new "recalibrated" series. A new data series was proposed also for the Group sunspot number. As a result, these two series which…

Solar and Stellar Astrophysics · Physics 2017-01-24 Katya Georgieva , Ali Kilcik , Yury Nagovitsyn , Boian Kirov

I discuss the issue of uncertainties in parton distributions and in the physical quantities which are determined in terms of them. While there has been significant progress on the uncertainties associated with errors on experimental data,…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. S. Thorne

Data from three solar observatories, Learmonth, Holloman, and San Vito, are used to study the variations in the average number of sunspots per sunspot group. It is found that the different types of sunspot groups and the number of sunspots…

Solar and Stellar Astrophysics · Physics 2017-10-06 K. Georgieva , A. Kilcik , Yu. Nagovitsyn , B. Kirov

We attempt to forecast the Sun's sunspot butterfly diagram in both space (i.e. in latitude) and time, instead of the usual one-dimensional time series forecasts prevalent in the scientific literature. We use a prediction method based on the…

Solar and Stellar Astrophysics · Physics 2017-09-11 Eurico Covas

We use 5 test data series to quantify putative discontinuities around 1946 in 5 annual-mean sunspot number or group number sequences. The series tested are: the original and new versions of the Wolf/Zurich/International sunspot number…

Solar and Stellar Astrophysics · Physics 2016-10-05 Mike Lockwood , Mathew J. Owens , Luke A. Barnard

The incorporation of systematic uncertainties into confidence interval calculations has been addressed recently in a paper by Conrad et al. (Physical Review D 67 (2003) 012002). In their work, systematic uncertainities in detector…

Data Analysis, Statistics and Probability · Physics 2009-11-10 Gary C. Hill

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
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