Splinter Meeting Activity

Solar and stellar activity and variability

Time: Thursday September 21, 14:00-16:30 and 17:00-19:00

Room: Auditorium MPS

Convenors: H. Peter [1], M. Käpylä [1], P. Käpylä [2], N. Krivova [1], A. Reiners [3], S. Shapiro [1], J. Warnecke [1]
[1] MPS, Göttingen; [2] AIP, Potsdam; [3] IAG, Göttingen

The activity of stars, including the Sun, is driven by the magnetic field generated in the dynamo process. When emerging at the surface the concentrations of the magnetic field change the brightness of the star. Expanding further into the upper atmosphere, they largely control its dynamics and heating. Understanding solar and stellar activity therefore requires modelling and observational studies from the stellar interior all the way to the chromosphere and corona. Significant progress over the last decade greatly improved our understanding of solar and stellar activity and variability. This is based on the availability of data from solar and stellar observations as well as in numerical modelling of the dynamo and of stellar atmospheres. In this splinter we plan to bring together observational and modelling studies of the magnetic activity and brightness variations from both, the solar and the stellar perspective.


14:00-14:45 Generation of magnetic field: the dynamo (Auditorium MPS)

14:00  Jörn Warnecke:
Dynamo mechanism for magnetic activity and cycles of stars

14:30  Mariangela Viviani:
Axi- to non-axisymmetric dynamo transition in stellar models with varying rotation rate

14:45-16:30 Signatures and variability of magnetic activity at the surface and chromosphere (Auditorium MPS)

14:45  Emre Isik:
Search for physical mechanisms underlying solar and stellar activity variations

15:15  Oleksii Kuzmychov:
Strong surface magnetic field on a brown dwarf

15:30  Charlotte Norris:
Spectral variability of photospheric radiation due to small-scale magnetic features

15:45  Veronika Witzke:
Effect of Metallicity on Stellar Brightness Variability

15:55  Theodosios Chatzistergos:
Connecting chromospheric emission to photospheric magnetic field

16:10  Hongrui Wang:
Measurements of Total Solar Irradiance on FengYun–3 Satellites, from 2008 to 2017

16:20  Discussion and 2-min advertisement of poster Patrick Schöfer:
Chromospheric Activity Indicators in Visible Light and Near Infrared

16:30-17:00 Coffee Break & Poster Session (Foyer Physics)

17:00-17:45 Signatures and variability of magnetic activity at the surface and chromosphere (cont.) (Auditorium MPS)

17:00  Chi Ju Wu:
Solar Irradiance Reconstruction over Holocene: A Consistent Multi-proxy Reconstruction

17:15  Eliana Maritza Amazo-Gomez:
GPS: A novel method to obtain stellar rotational periods

17:30  Timo Reinhold:
Evidence for photometric activity cycles in 3203 Kepler stars

17:45-19:00 X-ray emission from hot plasma and variability (Auditorium MPS)

17:45  Stefan Czesla:
X-ray emission and activity in late-type stars

18:15  Nina-Elisabeth Nemec:
The XUV Sun in Time

18:30  Hardi Peter:
Scaling MHD models of solar active regions to more active stars

18:45  Discussion

Related contributions

PresentationTitleType PDF
PourabdianDeep focusing in time-distance helioseismologyPoster PDF
ProxaufSolar near-surface flows from ring-diagram helioseismologyPoster PDF
SchöferChromospheric Activity Indicators in Visible Light and Near InfraredPoster PDF
YangA Possible Improvement on Helioseismic HolographyPoster PDF