Superflares , which are strong explosions on stars , have been well studied with the progress of space time-domain astronomy .
In this work , we present the study of superflares on solar-type stars using Transiting Exoplanet Survey Satellite ( TESS ) data .
Thirteen sectors of observations during the first year of the TESS mission have covered the southern hemisphere of the sky , containing 25,734 solar-type stars .
We verified 1216 superflares on 400 solar-type stars through automatic search and visual inspection with 2 minute cadence data .
Our result suggests a higher superflare frequency distribution than the result from Kepler .
This may be because the majority of TESS solar-type stars in our dataset are rapidly rotating stars .
The power-law index \gamma of the superflare frequency distribution ( dN / dE \propto E ^ { - \gamma } ) is constrained to be \gamma = 2.16 \pm 0.10 , which is a little larger than that of solar flares but consistent with the results from Kepler .
Because only seven superflares of Sun-like stars are detected , we can not give a robust superflare occurrence frequency .
Four stars are accompanied by unconfirmed hot planet candidates .
Therefore , superflares may possibly be caused by stellar magnetic activities instead of planet-star interactions .
We also find an extraordinary star , TIC43472154 , which exhibits about 200 superflares per year .
In addition , the correlation between the energy and duration of superflares ( T _ { \text { duration } } \propto E ^ { \beta } ) is analyzed .
We derive the power-law index to be \beta = 0.42 \pm 0.01 , which is a little larger than \beta = 1 / 3 from the prediction according to magnetic reconnection theory .