Results 1 to 10 of about 413,287 (118)
ACTIVITY-BRIGHTNESS CORRELATIONS FOR THE SUN AND SUN-LIKE STARS [PDF]
The Astrophysical Journal, 2011 We analyze the effect of solar features on the variability of the solar irradiance in three different spectral ranges. Our study is based on two solar-cycles' worth of full-disk photometric images from the San Fernando Observatory, obtained with red, blue and Ca II K-line filters.
Preminger, Dora +2 more
openaire +2 more sources
Active Latitude Oscillations Observed on the Sun [PDF]
Solar Physics, 2016 Accepted for publication by Solar ...
Kilcik, Ali +4 more
openaire +4 more sources
THE ORIGIN OF ENHANCED ACTIVITY IN THE SUNS OF M67 [PDF]
The Astrophysical Journal, 2009 We report the results of the analysis of high resolution photospheric line spectra obtained with the UVES instrument on the VLT for a sample of 15 solar-type stars selected from a recent survey of the distribution of H and K chromospheric line strengths in the solar-age open cluster M67.
Reiners, Ansgar, Giampapa, Mark S.
openaire +3 more sources
Solar neutrinos as indicators of the Sun’s activity [PDF]
International Journal of Modern Physics A, 2019 Opportunity of the solar flares (SFs) prediction observing the solar neutrino fluxes is investigated. In three neutrino generations, the evolution of the neutrino flux traveling the coupled sunspots (CSs) which are the SF source is considered. It is assumed that the neutrinos possess both the dipole magnetic moment and the anapole moment while the ...
O. M. Boyarkin, I. O. Boyarkina
openaire +4 more sources
Faculae Cancel out on the Surfaces of Active Suns
The Astrophysical Journal Letters, 2022 Abstract Surfaces of the Sun and other cool stars are filled with magnetic fields, which are either seen as dark compact spots or more diffuse bright structures like faculae. Both hamper detection and characterization of exoplanets, affecting stellar brightness and spectra, as well as transmission spectra.
Nèmec, N.-E. +15 more
openaire +6 more sources
MAGNETO-ACTIVE LONGITUDES IN THE SUN AND STARS
Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, 2023 An overview of studies of long-term increased magnetic activity in two discrete longitudinal intervals observed on the Sun and on the surface of stars of certain types is reviewed. Active longitudes on the Sun were first discovered at the end of the 19th century.
openaire +2 more sources
Space Science Reviews, 1981 A brief summary is given of observations which will be required to investigate further the structure and energy balance of active regions.
openaire +2 more sources
The EUV spectrum of the Sun: Quiet- and active-Sun irradiances and chemical composition [PDF]
Astronomy & Astrophysics, 2019 We benchmark new atomic data against a selection of irradiances obtained from medium-resolution quiet-Sun spectra in the extreme ultraviolet (EUV), from 60 to 1040 Å. We used as a baseline the irradiances measured during solar minimum on 2008 April 14 by the prototype (PEVE) of the Solar Dynamics Observatory Extreme ultraviolet Variability Experiment ...
openaire +2 more sources
CMEs and active regions on the sun [PDF]
Advances in Space Research, 2013 The relationship between active regions (ARs) and coronal mass ejections (CMEs) is studied. For this purpose a statistical analysis of 694 CMEs associated with ARs was carried out. We considered the relationship between properties of the CMEs and ARs characterized using the McIntosh classification.
Michałek, Grzegorz, Yashiro, Seiji
openaire +2 more sources
Millimeter and Microwave Activity of the Sun [PDF]
Symposium - International Astronomical Union, 1990 The emission of solar flares at millimeter wavelengths is of great interest both in its own right and because it is generated by the energetic electrons which also emit gamma rays. Since high-resolution imaging at gamma-ray energies is not presently possible, millimeter observations can act as a substitute.
M. R. Kundu, S. M. White
openaire +1 more source