Stochastic Modelling of Solar Cycle | Celine Didier Dupont
| | Abstract | The solar magnetic field has been analysed through many different aspects, for example by investigating the driving factors that generate the magnetic field, i.e the solar dynamo, or throughout observations of its evolution on the solar surface by analysing sunspots structures and physical features. In the present work, we focus on the large scale evolution of the magnetic field at the solar surface. Firstly, we investigate the flux transport process generated by the supergranular diffusion, the differential rotation and the meridional flow. Based on a recently reviewed flux transport numerical code, a new transport code is developed and implemented in the software R. This new numerical method is a combination of a finite volume and spectral method. The emergence of new magnetic fluxes, pairs of sunspots as Bipolar Magnetic Regions, will be simulated with help of statistical tools, as a Poisson point process in time, making it a stochastic process. On this basis, a full solar cycle is simulated which data are converted into a light curve. With help of real high precision data from the ESA/NASA SOHO spacecraft, VIRGO (Variability of solar IRradiance and Gravity Oscillations), we compare the main features of the spectrum of the simulated light curve to the ones of the empirical data on a short term timescale, i.e six months, and investigate the influence of some of the parameters on a lightcurve. The light curve resulting from the simulation model of the emergence and evolution of the BMR reproduces the main features of the real data. It is even possible by adjusting some of the parameters to reproduce unusual periods in the simulated light curve, corresponding to periods found in the VIRGO data. | | Type | Master's thesis [Industrial collaboration] | | Year | 2014 | | Publisher | Technical University of Denmark, Department of Applied Mathematics and Computer Science | | Address | Richard Petersens Plads, Building 324, DK-2800 Kgs. Lyngby, Denmark, compute@compute.dtu.dk | | Series | DTU Compute M.Sc.-2014 | | Note | | | Electronic version(s) | [pdf] | | Publication link | http://www.compute.dtu.dk/English.aspx | | BibTeX data | [bibtex] | | IMM Group(s) | Mathematical Statistics |
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