white dwarfs Binaries: close 1 Binary star 1 Brown dwarfs 1 Compact objects 1 Degenerate plasma 1 Dwarf binaries 1 Energy source 1 Gamma rays 1 Gravity waves 1 Landau quantization 1 Main sequence stars 1 Recombination energy 1 Star: individual: SDSS j1411+2009, SDSS j1205-0242, WD 1032+011, ZTF j0038+2030, WD 0137-349, NLTT 5306, SDSS j1557+0916, EPIC 212235321 1 Stars: individual: proxima Centauri 1 Supernovae 1 White dwarfs 1 binaries: close 1 brown dwarfs 1 dense matter 1 diffusion 1 electron trapping 1 instability analysis 1 ion acoustic wave 1 methods: numerical 1 plasmas 1 stars: individual: SDSS J1411+2009, SDSS J1205-0242, WD 1032+011, ZTF J0038+2030, WD 0137-349, NLTT 5306, SDSS J1557+0916, EPIC 212235321 1 stars: interiors 1