Stability of an active longitude of the giant PZ Mon

TL;DR

This study analyzes 15 years of photometric data of the active giant PZ Mon, demonstrating the stability of its active longitude and suggesting the secondary component influences stellar activity.

Contribution

It provides long-term observational evidence of the stable active longitude on PZ Mon and links it to the secondary star, using new and existing photometric data.

Findings

Active longitude remains stable over 15 years.

Small deviations are due to differential rotation or spot distribution.

Active longitude's stability indicates influence of the secondary component.

Abstract

Analysis of photometric data of the active giant PZ Mon is presented. Using ASAS-3 project data and new more accurate photometry we establish that during 15 years of PZ Mon CCD observations the light curve remains stable, and consequently a longitude of the active spotted area is stable. The small deviations may be explained by differential rotation or inhomogeneous distribution of spots on the active hemisphere of PZ Mon. The stability of the active longitude and it's location on the PZ Mon surface indicates on the secondary component as reason of stellar activity.