Temporal Variation of Flare Occurrence Rates via the Spot Evolution on the Sun and Solar-type Stars

Abstract

The spot evolution on the Sun and solar-type stars is important for understanding the nature of consequential flaring activity. This study statistically investigates the variance of flare occurrence rate through the time evolution of spots on the Sun and solar-type stars. We have compiled the 28-year catalogs of solar flares and their source sunspots obtained from solar surface observations by NOAA and GOES for the Sun. Also, we combined the cataloged stellar flares with the time evolution of starspots estimated by light curves obtained by the 4-year Kepler mission for solar-type stars. For the obtained 24124 solar flares and 180 stellar flares, we calculate the flare occurrence distribution with respect to $t_{\mathrm{flare}}-t_{\max }$, which represents the timing of flare through the spot evolution, where $t_{\mathrm{flare}}$ is the flare occurrence time, and $t_{\max }$ is the time when the source spot takes its maximum area. When normalized by the spot lifetime, we found that the flare occurrence distribution for $t_{\mathrm{flare}}-t_{\max }$ shows a similar distribution regardless of spot size or flare energy, suggesting that the Sun and the solar-type star share the same physical process in the spot-to-flare activity. On this basis, we propose a formula for the time variation of the flare occurrence rate per spot. Also, the correlation between the temporal variation of flare occurrence rate and the time evolution of spot area and the lack of difference in flare occurrence rate between the emergence and decaying phases provide a milestone for the nature of flare-productive spots.

arXiv comment21 pages, 12 figures, 2 tables. Accepted for publication in The Astrophysical Journal

References in corpus (51)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Gaia Data Release 2. Summary of the contents and survey properties
• The PLATO 2.0 Mission
• The Solar Cycle
• Rotation Periods of 34,030 Kepler Main-Sequence Stars: The Full Autocorrelation Sample
• The surprising magnetic topology of tauSco: fossil remnant or dynamo output?
• Superflares on Solar Type Stars Observed with Kepler I. Statistical Properties of Superflares
• Global Energetics of Thirty-Eight Large Solar Eruptive Events
• Kepler Flares I. Active and Inactive M dwarfs
• Revised Radii of Kepler Stars and Planets Using Gaia Data Release 2
• Revised Stellar Properties of Kepler Targets for the Q1-17 (DR25) Transit Detection Run
• Flare-productive active regions
• A Revised Effective Temperature Scale for the Kepler Input Catalog
• Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets
• Can Superflares Occur on Our Sun?
• Statistical properties of superflares on solar-type stars based on 1-min cadence data
• Superflares on Solar-Type Stars Observed with Kepler II. Photometric Variability of Superflare-Generating Stars : A Signature of Stellar Rotation and Starspots
• Magnetic Properties of Solar Active Regions that Govern Large Solar Flares and Eruptions
• Rotation, differential rotation, and gyrochronology of active Kepler stars
• Extreme solar events
• Do Kepler superflare stars really include slowly-rotating Sun-like stars ? - Results using APO 3.5m telescope spectroscopic observations and Gaia-DR2 data -
• Making Sense of Sunspot Decay I: Parabolic Decay Law and Gnevyshev-Waldmeier Relation
• Flare Statistics for Young Stars from a Convolutional Neural Network Analysis of $\text{TESS}$ Data
• Numerical simulations of active region scale flux emergence: From spot formation to decay
• The Sun is less active than other solar-like stars
• Statistical Properties of Superflares on Solar-type Stars: Results Using All of the Kepler Primary Mission Data
• Asteroseismic detection of latitudinal differential rotation in 13 Sun-like stars
• Differential rotation in K, G, F and A stars
• Starspot activity and superflares on solar-type stars
• Superflares on solar-type stars from the first year observation of TESS
• Powering Stellar Magnetism: Energy Transfers in Cyclic Dynamos of Sun-like Stars
• Lifetimes and Emergence/Decay Rates of Star Spots on Solar-type Stars Estimated by Kepler Data in Comparison with Those of Sunspots
• Superflares, chromospheric activities and photometric variabilities of solar-type stars from the second-year observation of TESS and spectra of LAMOST
• Numerical Simulations of Flare-productive Active Regions: delta-sunspots, Sheared Polarity Inversion Lines, Energy Storage, and Predictions
• Investigating the Rotational Phase of Stellar Flares on M dwarfs Using K2 Short Cadence Data
• High Dispersion Spectroscopy of Solar-type Superflare Stars. II. Stellar Rotation, Starspots, and Chromospheric Activities
• Numerical simulations of sunspot decay: On the penumbra -- Evershed flow -- moat flow connection
• Superflares and Variability in Solar-Type Stars with $TESS$ in the Southern Hemisphere
• Magnetic flux transport on active cool stars and starspot lifetimes
• Impact of Stellar Superflares on Planetary Habitability
• On Sunspot and Starspot Lifetimes
• Modeling of differential rotation in rapidly rotating solar-type stars
• Increasing Lifetime of Recurrent Sunspot Groups within the Greenwich Photoheliographic Results
• Magnetic Flux Loss and Flux Transport in a Decaying Active Region
• Starspot mapping with adaptive parallel tempering. II. Application to TESS data for M-dwarf flare stars, AU Microscopii, YZ Canis Minoris, and EV Lacertae
• Sun-like stars produce superflares roughly once per century
• Temporal Evolution of Spatially-Resolved Individual Star Spots on a Planet-Hosting Solar-type Star: Kepler 17
• Reliability of stellar inclination estimated from asteroseismology: analytical criteria, mock simulations and Kepler data analysis
• The Connection between Starspots and Flares on Main-Sequence Kepler Stars
• Starspot mapping with adaptive parallel tempering I: Implementation of computational code
• The connection between starspots and superflares: a case study of two stars