Conveners
Penumbra formation. Magnetic effects, umbral dots, light bridges, etc.
- Aaron Birch (Max Planck Institute for Solar System Research)
Penumbra formation. Magnetic effects, umbral dots, light bridges, etc.
- Aaron Birch (Max Planck Institute for Solar System Research)
Penumbra formation. Magnetic effects, umbral dots, light bridges, etc.
- Illa Losada (Nordita & Stockholm University)
Penumbra formation. Magnetic effects, umbral dots, light bridges, etc.
- Hannah Schunker (Max Planck Institute for Solar System Research)
Alan Title
(Stanford Lockheed Institute)
12/03/2015, 14:30
In this study we tested for groups of flares (flare
clusters) in which successive flares occur within a fixed
time - the linking window. The data set used is the flare
waiting times provided by the X-ray flare detectors on the
Geostationary Operational Environmental Satellites (GOES).
The study was limited to flares of magnitude C5 and greater
obtained during cycle 23. While many flares...
Rolf Schlichenmaier
(Kiepenheuer-Institut fuer Sonnenphysik)
12/03/2015, 16:45
The various ways of energy transport in radiatively driven
magnetoconvection determine the structure of sunspots. At
first glance, sunspots are composed of a dark umbra and a
brighter penumbra. The darkness of the umbra is readily
explained by the tension of the magnetic field lines that
supresses convection. Yet, it is clear that even in the
darkest part of the umbra, radiative and...
Sara Esteban Pozuelo
(Instituto de Astrofísica de Andalucía (IAA-CSIC))
12/03/2015, 17:25
We study the evolution of small-scale convective motions in
a sunspot located close to disk center using a temporal
sequence of high resolution observations acquired at the
SST. We calculate Dopplergrams in photospheric layers and
filter them for subsonic oscillations. Lateral downflows
appear everywhere in the center side penumbra as small,
weak, redshifted patches next to blueshifted...
Matthias Rempel
(HAO/NCAR)
13/03/2015, 09:00
We present a series of high-resolution sunspot simulations
that cover a time span of up to 100 hours. The simulation
domain covers the upper 18 Mm of the convection zone and we
use open boundaries that do not maintain the initial field
structure against decay driven by convective motions. We
consider two setups: A sunspot simulation with penumbra, a
"naked-spot" simulation in which we...
Åke Nordlund
13/03/2015, 09:40
Discussion of factors that influence the structure of (model
an real) sunspots and their penumbrae
Jaime de la Cruz Rodriguez
(Institute for Solar Physics, Stockholm University)
13/03/2015, 10:00
We present new high-resolution spectro-polarimetric Ca II
8542 observations of umbral flashes in sunspots. At nearly
0.18", and spanning about one hour of continuous
observation, this is the most detailed dataset published
thus far. Our study involves non-LTE inversions to quantify
temperatures, mass flows and the full magnetic field vector
geometry.
Göran Scharmer
(Kungliga Vetenskapsakademien)
13/03/2015, 10:50
During the last ten years, our understanding of sunspot fine
structure and heating through convection has improved
dramatically thanks to a combination of numerical MHD
simulations and high-resolution imaging and
spectropolarimetric data. I will summarise some of the
recent observations, with emphasis on data from the Swedish
1-m Solar Telescope (SST), and how these and simple...
Nikola Vitas
(Instituto de Astrofísica de Canarias)
13/03/2015, 11:10
The three-dimensional simulation of magnetoconvection in a
sunspot umbra by V\"ogler and Sch\"ussler (2006) was an
important step towards more realistic sunspot and
active-region simulations. In spite of the idealized
boundary conditions in this simulation (it describes a
periodic umbra-like atmosphere isolated from the surrounding
quiet sun) it predicted the typical coffee-bean shape...
Serge Koutchmy
(Institut d'Astrophysique de Paris CNRS & UPMC)
13/03/2015, 11:30
The free of seeing effects high resolution images of a
single sunspot observed near the centre of the Sun with the
SOT (Hinode) are accuratly deconvolved. The new PSF deduced
from the transit of Venus and from the extreme limb data
takes into account both the diffraction of origin smearing
and the stray light from the optics. It considerably
improved the details near the diffraction...
