Results 61 to 70 of about 2,749 (159)
Astronomy & AstrophysicsTidal deformation breaks the axisymmetric structure of stars, and this may affect stellar activity. This effect has been demonstrated in theoretical analyses and simulations, but it lacks observational support.
Jia-Xin Wang +7 more
semanticscholar +1 more source
Are Starspots and Plages Co-located on Active G and K Stars? [PDF]
Astronomical Journal, 2018 We explore the connection between starspots and plages of three main-sequence stars by studying the chromospheric and photospheric activity over several rotation periods.
B. Morris +6 more
semanticscholar +1 more source
Starspot Imaging Using VRI Photometry [PDF]
Symposium - International Astronomical Union, 1986 Recent progress on maximum-entropy imaging of stellar surface brightness distributions using VRI photometry and Doppler-broadened absorption line profiles is reported. VRI photometry generally provides tighter constraints on starspot configurations than does Doppler imaging (which requires the use of large telescopes).
openaire +1 more source
Starspots on late-type stars and their correlation with flare activity
, 2018 Recent space-based observations (e.g., Kepler mission) found thousands of ``superflares’’ on G-, K-, and M-type stars. These superflare stars show quasi-periodic brightness variations caused by the rotation of the star with starspots.
Honda, Satoshi (5266576) +15 more
core +1 more source
Starspot photometry with robotic telescopes [PDF]
Astronomy and Astrophysics Supplement Series, 1997 We report on the progress of our ongoing photometric monitoring program of spotted late-type stars with automatic photoelectric telescopes (APTs) on Mt. Hopkins in Arizona and on Mt. Etna in Sicily. We present 9 250 differential UBV and/or observations for altogether 23 chromospherically active stars, singles and binaries, pre main sequence and post ...
K. G. Strassmeier +3 more
openaire +1 more source
A Flexible Model for Investigating the Properties of Starspots: Model Characterization
, 2018 Starspots are sites of intense magnetic fields near a star’s optical surface that actively suppress convective flows causing the area to be dimmer and cooler than the surrounding ambient photosphere.
Ash, Amanda +5 more
core +1 more source
Calibration of Differential Light Curves for Physical Analysis of Starspots [PDF]
Astrophysical Journal, 2018 This paper presents detailed consideration of methodologies to calibrate differential light curves for accurate physical starspot modeling. We use the Sun and starspot models as a testbed to highlight some factors in this calibration that that have not ...
G. Basri
semanticscholar +1 more source
Molecules as magnetic probes of starspots [PDF]
Astronomy & Astrophysics, 2015 Stellar dynamo processes can be explored by measuring the magnetic field. This is usually obtained using the atomic and molecular Zeeman effect in spectral lines. While the atomic Zeeman effect can only access warmer regions, the use of molecular lines is of advantage for studying cool objects.
Afram, N., Berdyugina, S. V.
openaire +2 more sources
The Young Planetary System K2-25: Constraints on Companions and Starspots [PDF]
Astronomical Journal, 2019 The abundance of planets with orbital periods of a few to tens of days suggests that exoplanets experience complex dynamical histories. Planets in young stellar clusters or associations have well-constrained ages and therefore provide an opportunity to ...
I. Kain +7 more
semanticscholar +1 more source
Starspots, stellar cycles and stellar flares: Lessons from solar dynamo models [PDF]
, 2016 In this review, we discuss whether the present solar dynamo models can be extrapolated to explain various aspects of stellar activity. We begin with a summary of the following kinds of data for solar-like stars: (i) data pertaining to stellar cycles from
A. Choudhuri
semanticscholar +1 more source