Spectral changes during a flare on an M-star

Background

M-stars are the most common host stars for extrasolar planet systems. Habitability may be a problem because many M-stars have frequent flares.

Goal

The goal of the project is to study the change in the spectrum when a flare occurs on an M-star.

Method

The RH 1.5D code is used to solve the equations of statistical equilibrium for a given model atom and model atmosphere.

Procedure

Adam Kowalski has made models of M-dwarf flares, using the RADYN code (Carlsson et al. 1992,Allred et al. 2015). See Kowalski et al. 2015 for a description of the physics during an M-dwarf flare as deduced from the model.

1. There are four 1D models of flares on M-dwarfs (/mn/stornext/u3/matsc/rh/Atmos/mflares/). These are

   radyn_out.F13_dpl_GRID_pt1s.ncdf
   tx.m2F12-37.max2F12_Ec37_d3.ncdf
   tx.m5F12-37.max5F12_Ec37_d3.ncdf
   tx.mF13-37.maxF13_Ec37_d3_dt0.1_10s.ncdf

   the three "tx" models all have a low cut-off energy of 37 keV and a power index of 3 (see Allred et al. 2015) but vary in maximum beam energy: 2e12, 5e12 and 1e13 erg/cm^2/s. The model from Kowalski et al. 2015 is radyn_out.F13_dpl_GRID_pt1s.ncdf.

2. Read the ncdf files and look at the atmosphere as function of time. Compare with the first model with the figures in Kowalski et al. 2015.

3. Use RH to calculate the spectrum as function of time

4. With different flare energies and area-factors, what are the effects on the total spectrum? on the UV spectrum?