# Flaring activity of Proxima Centauri from TESS observations: quasi-periodic oscillations during flare decay and inferences on the habitability of Proxima b

## TL;DR

This study analyzes TESS observations of Proxima Centauri, revealing frequent flares, quasi-periodic oscillations during some flares, and implications for the habitability of Proxima b based on flare activity.

## Contribution

It provides the first detailed analysis of flare frequency, energies, and oscillations of Proxima Centauri from TESS data, informing habitability assessments.

## Key findings

- Flare rate of 1.49 events per day.
- Superflares of 10^{33} ergs occur thrice annually.
- Quasi-periodic oscillations observed during flare decay.

## Abstract

We analyze the light curve of the M5.5 dwarf Proxima Centauri obtained by the TESS in Sectors 11 and 12. In the $\approx 50$ day-long light curve we identified and analyzed 72 flare events. The flare rate was 1.49 events per day, in total, 7.2% of the data was classified as flaring. The estimated flare energies were in the order of $10^{30}-10^{32}$ ergs in the TESS passband ($\approx4.8\times$ higher in bolometric energies, but in the same order of magnitude). Most of the eruptions appeared in groups. Two events showed quasi-periodic oscillations during their decay phase with a time scale of a few hours, that could be caused by quasiperiodic motions of the emitting plasma or oscillatory reconnection. From the cumulative flare frequency distribution we estimate that superflares with energy output of $10^{33}$ ergs are expected to occur three times per year, while a magnitude larger events (with $10^{34}$ ergs) can occur every second year. This reduces the chances of habitability of Proxima Cen b, although earlier numerical models did not rule out the existence of liquid water on the planetary surface. We did not find any obvious signs of planetary transit in the light curve.