Thermal signature in global MHD simulations of the solar convection zone
Jean-François Cossette
Université de Montréal
Total solar irradiance (TSI) is the total power of the solar
electromagnetic radiation integrated over all wavelengths that is
received per unit area by a detector placed at 1 AU from the Sun.
The TSI has been measured almost continuously since the 1980s by
several space instruments and is now know to vary in phase with the
11-year solar sunspot number with an amplitude corresponding to 0.1
percent of its mean value. Although most of the variability can be
explained by taking into account cumulative effects of sunspots, faculae
and other magnetic structures present at the Sun's surface, the
question whether or not global structural changes of the star may
also contribute to the irradiance cycle remains unanswered. Recent
global MHD simulations of the solar convection zone (SCZ) produced
large-scale magnetic cycles with polarity reversals similar in many
aspects to those observed on the Sun. These simulations also show a
thermal signature pervading the whole SCZ that varies in phase with
the magnetic cycle and therefore offer the chance to assess the impact
that global structural changes would have on TSI fluctuations.
Date: | Jeudi, le 11 avril 2013 |
Heure: | 11:30 |
Lieu: | Université de Montréal |
| Pavillon Roger-Gaudry, local D-460 |
Contact: | Jean-François Cossette |
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