The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies-VIII. A Census of Long-Period Variable Stars across the Andromeda Dwarf Satellite System

Hedieh Abdollahi; Atefeh Javadi; Jacco Th. van Loon; Iain McDonald; Mahdi Abdollahi; Elham Saremi; Habib G. Khosroshahi; László Molnár; Hamidreza Mahani

arXiv · 2601.06924

The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies-VIII. A Census of Long-Period Variable Stars across the Andromeda Dwarf Satellite System

Hedieh Abdollahi·Atefeh Javadi·Jacco Th. van Loon·Iain McDonald·Mahdi Abdollahi·Elham Saremi·Habib G. Khosroshahi·László Molnár·Hamidreza Mahani

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Abstract

We present a comprehensive catalog, in the Sloan $i$ and Harris $V$ filters, of long-period variable (LPV) stars in the spheroidal dwarf satellites of the Andromeda galaxy, based on a dedicated survey for variable stars in Local Group dwarf systems. Using photometric time-series data obtained with the Wide Field Camera (WFC) on the 2.5 m Isaac Newton Telescope (INT), we identify approximately 2800 LPV candidates across 17 Andromeda satellites, spanning a broad range in luminosity and variability amplitude. This study is accompanied by a public data release that includes two comprehensive catalogs, a catalog of the complete stellar populations for each galaxy and a separate catalog listing all identified LPV candidates. Both are available through CDS/VizieR and provide a valuable resource for investigating quenching timescales, stellar mass distributions, and the effects of mass-loss and dust production in dwarf galaxies. We derive updated structural parameters, including newly measured half-light radii, and determine distance moduli using the Tip of the Red Giant Branch (TRGB) method with Sobel-filter edge detection, yielding values between $23.38\pm0.06$ and $25.35\pm0.06$ mag.

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Hedieh Abdollahi, Atefeh Javadi, Jacco Th. van Loon, Iain McDonald, Mahdi Abdollahi, Elham Saremi, Habib G. Khosroshahi, László Molnár, Hamidreza Mahani. 2026-01-11. The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies-VIII. A Census of Long-Period Variable Stars across the Andromeda Dwarf Satellite System. https://arxiv.org/abs/2601.06924

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