Probability Distribution Functions of Sunspot Magnetic Flux
نویسندگان
چکیده
Abstract We investigated the probability distributions of sunspot area and magnetic flux by using data from Royal Greenwich Observatory USAF/NOAA. constructed a sample 2995 regions with maximum-development areas ≥500 MSH (millionths solar hemisphere), covering 146.7 yr (1874–2020). The were fitted power-law distribution four two-parameter (tapered-power-law, gamma, lognormal, Weibull distributions). model was unfavorable compared to models in terms AIC, not acceptable according classical Kolmogorov–Smirnov test. lognormal excluded because their behavior extended smaller ( S ≪ 500 MSH) do connect previously published results. Therefore, our choices tapered-power-law gamma distributions. portion found have power exponent 1.35–1.9. Due exponential falloff these distributions, expected frequencies large sunspots are low. largest group observed had an 6132 MSH, frequency larger than 10 4 estimated be every 3–8 × yr. also Sun-as-a-star total areas. covered on record 1.67% visible disk, can up 2.7% artificially increasing lifetimes evolution model. These values still those active Sun-like stars.
منابع مشابه
Evolution of a Magnetic Flux Tube in a Sunspot Penumbra
The motion of an individual magnetic flux tube inside the penumbra of a sunspot is studied numerically. Here, we present preliminary results. The thin flux tube approximation together with a simplified radiative heat exchange with the surroundings is used to study the evolution of a flux tube embedded into a background given by a global magneto-static sunspot model. The investigation is underta...
متن کاملDistribution of sunspot groups from asymmetric rising flux loops
Rising magnetic flux loops in the solar convection zone develop an asymmetric shapewith a flat preceding part and a steeper following part with respect to the direction of solar rotation. By a statistical analysis of newly forming sunspot groups we test the conjecture that this geometrical asymmetry leads to an asymmetric distribution of secondary spot groups originating from the legs of the sa...
متن کاملDecreasing Sunspot Magnetic Fields Explain Unique 10.7 cm Radio Flux
Infrared spectral observations of sunspots from 1998-2011 have shown that on average sunspots changed; the magnetic fields weakened and the temperatures rose. The data also show that sunspots or dark pores can only form at the solar surface only if the magnetic field strength exceeds about 1500 Gauss. Sunspots appear at the solar surface with a variety of field strengths, and during the period ...
متن کاملOn the Concavity of Multivariate Probability Distribution Functions on the Concavity of Multivariate Probability Distribution Functions
We prove that the multivariate standard normal probability distribution function is concave for large argument values. The method of proof allows for the derivation of similar statements for other types of multivariate probability distribution functions too. The result has important application, e.g., in probabilistic constrained stochastic programming problems.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2023
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/1538-4357/aca28a