Saved in:
Bibliographic Details
Main Authors: Fonseca, Andrew, Dodson-Robinson, Sarah
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2411.05476
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915030539173888
author Fonseca, Andrew
Dodson-Robinson, Sarah
author_facet Fonseca, Andrew
Dodson-Robinson, Sarah
contents Based on radial velocities, EXORAP photometry, and activity indicators, the HADES team reported a 16.3-day rotation period for the M dwarf GJ 3942. However, an RV--H$α$ magnitude-squared coherence estimate has significant peaks at frequencies 1/16 cycles/day and 1/32 cycles/day. We re-analyze HADES data plus Hipparcos, SuperWASP, and TESS photometry to see whether the rotation period could be 32 days with 16-day harmonic. SuperWASP shows no significant periodicities, while the Hipparcos observing cadence is suboptimal for detecting 16- and 32-day periodicities. Although the average TESS periodogram has peaks at harmonics of 1/16 cycles/day, the harmonic sequence is not fully resolved according to the Rayleigh criterion. The TESS observations suggest a 1/16 cycles/day rotation frequency and a 1/32 cycles/day subharmonic, though resolution makes the TESS rotation detection ambiguous.
format Preprint
id arxiv_https___arxiv_org_abs_2411_05476
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Examining the rotation of the planet-hosting M dwarf GJ 3942
Fonseca, Andrew
Dodson-Robinson, Sarah
Solar and Stellar Astrophysics
Earth and Planetary Astrophysics
Based on radial velocities, EXORAP photometry, and activity indicators, the HADES team reported a 16.3-day rotation period for the M dwarf GJ 3942. However, an RV--H$α$ magnitude-squared coherence estimate has significant peaks at frequencies 1/16 cycles/day and 1/32 cycles/day. We re-analyze HADES data plus Hipparcos, SuperWASP, and TESS photometry to see whether the rotation period could be 32 days with 16-day harmonic. SuperWASP shows no significant periodicities, while the Hipparcos observing cadence is suboptimal for detecting 16- and 32-day periodicities. Although the average TESS periodogram has peaks at harmonics of 1/16 cycles/day, the harmonic sequence is not fully resolved according to the Rayleigh criterion. The TESS observations suggest a 1/16 cycles/day rotation frequency and a 1/32 cycles/day subharmonic, though resolution makes the TESS rotation detection ambiguous.
title Examining the rotation of the planet-hosting M dwarf GJ 3942
topic Solar and Stellar Astrophysics
Earth and Planetary Astrophysics
url https://arxiv.org/abs/2411.05476