# Infrared variability of young solar analogs in the Lagoon Nebula

**Authors:** C. Ordenes-Huanca, M. Zoccali, A. Bayo, J. Cuadra, R. Contreras Ramos, L. A. Hillenbrand, I. Lacerna, S. Abarzua, C. Avendaño, P. Diaz, I. Fernandez, G. Lara  
**arXiv:** [2210.09242](https://arxiv.org/abs/2210.09242)  
**Date:** 2022-10-17  
**Summary page:** https://www.summarizepaper.com/en/paper/2210.09242v1/

## Key points

- The Lagoon Nebula (M8) region has a large number of low-mass pre-main sequence stars known as T Tauri stars
- T Tauri stars are intrinsically variable due to intense magnetic fields and the presence of surrounding disks
- A catalog of light curves for 379 T Tauri stars in the Lagoon Nebula region was compiled using VVVX survey data in the Ks-band
- The light curves were classified based on their degree of periodicity and asymmetry to better understand the physical processes responsible for their variation
- Periods were compared with those found in literature on much shorter baselines, allowing researchers to prove that magnetically active regions remain stable for several years in 126 stars
- Near-IR data were compared with optical Kepler/K2 light curves when available, providing insight into how brightness variations manifest across different bands
- Periodicity in both bands was fairly consistent but asymmetry depended on the amplitude of bursts or dips events and observation cadence
- This research sheds new light on the mechanisms responsible for brightness variations observed among T Tauri stars and provides valuable insights into how these young solar analogs evolve over time.

## Summary

The Lagoon Nebula (M8) region is home to a large number of low-mass pre-main sequence stars known as T Tauri stars. These stars are intrinsically variable due to the intense magnetic fields they possess, which create dark spots on their surface that introduce periodic variations in brightness as a result of rotation. Additionally, the presence of surrounding disks can generate flux variations through variable extinction or accretion, leading to either a decrease or increase in brightness respectively. In this study, a catalog of light curves for 379 T Tauri stars in the Lagoon Nebula region was compiled using VVVX survey data in the Ks-band. All these stars were already classified as pre-MS based on other indicators and the data presented here spanned over eight years, providing a unique follow-up time for these sources at this wavelength. The light curves were classified based on their degree of periodicity and asymmetry to better understand the physical processes responsible for their variation. The periods were compared with those found in literature on much shorter baselines, allowing researchers to prove that magnetically active regions remain stable for several years in 126 stars. Furthermore, near-IR data were compared with optical Kepler/K2 light curves when available, providing insight into how brightness variations manifest across different bands. The study found that periodicity in both bands was fairly consistent but asymmetry depended on the amplitude of bursts or dips events and observation cadence. This research sheds new light on the mechanisms responsible for brightness variations observed among T Tauri stars and provides valuable insights into how these young solar analogs evolve over time.