Tuesday

M dwarfs make up 70% of the stars in the solar neighbourhood. They are small, cool main sequence stars with temperatures in the range of 2400 – 3400 K and a radius between 0.20 – 0.63 Msun. In solar type stars, it is well known that the magnetic field is generated by the way of a dynamo which originates in the tachocline. However, by M4V spectral class (~0.2Msun) the stellar interior changes dramatically, becoming fully convective. This is key in the study of stellar flares on M dwarfs as with no radiative zone or tachocline you expect the stars to have no magnetic field and therefore be inactive. However, some stars show strong flaring activity suggesting stars later than M4 can have magnetic fields and therefore, the magnetic field of the stars is generated by a different mechanism from that which generated the field in solar like stars. We have obtained an ensemble of short cadence K2 data for 25 M dwarfs which will be used for the analysis of stellar flare statistics. Stellar flares are used as a proxy for stellar activity in general on the sample of M dwarfs. Bearing in mind that stars after M4 are fully convective and we know late M stars do show activity, the question remains how do these stars produce a magnetic field strong enough to produce flaring events and how much variability can be seen in the spectral sub-types? In addition to this, do more energetic flares come from stars with higher mass or rotation?