The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies. VI. The Star Formation History and Dust Production in Andromeda IX

Abdollahi, Hedieh; Javadi, Atefeh; Mirtorabi, Mohammad Taghi; Saremi, Elham; van Loon, Jacco Th.; Khosroshahi, Habib. G. G.; McDonald, Iain; Khalouei, Elahe; Mahani, Hamidreza; Aghdam, Sima Taefi; Saberi, Maryam; Torki, Maryam

Abstract

We present a photometric study of the resolved stellar populations in Andromeda IX (And IX), the closest satellite to M31, a metal-poor and low-mass dwarf spheroidal galaxy. We estimate a distance modulus of 24.56(-0.05)(+0.15) mag based on the tip of the red giant branch. By probing the variability of asymptotic giant branch stars, we study the star formation history of And IX. We identified 50 long-period variables (LPVs) in And IX using the Isaac Newton Telescope in two filters, the Sloan i ' and Harris V. In this study, we selected LPVs within two half-light radii with amplitudes in the range of 0.2-2.20 mag. It is found that the peak of star formation reaches similar to 8.2 +/- 3.1 x 10(-4) M-circle dot yr(-1) at approximate to 6 Gyr ago. Our findings suggest an outside-in galaxy formation scenario for And IX with a quenching occurring 3.65(-0.13)(+1.52) Gyr ago with a star formation rate (SFR) in the order of 2.0 x 10(-4) M-circle dot yr(-1) at redshift <0.5. We calculate the total stellar mass by integrating the SFR within two half-light radii similar to 3.0 x 10(5) M-circle dot. By employing spectral energy distribution fitting for the observed LPVs in And IX, we evaluate a mass-loss rate in the range of 10(-7) <= (M) over dot <= 10(-5) M-circle dot yr(-1). Finally, we show that the total mass deposition to the interstellar medium (ISM) is similar to 2.4 x 10(-4) M-circle dot yr(-1) from the C- and O-rich types of dust-enshrouded LPVs. The ratio of the total mass returned to the ISM by LPVs to the total stellar mass is similar to 8.0 x 10(-10) yr(-1), and so at this rate it would take similar to 1 Gyr to reproduce this galaxy.

Citation

Abdollahi, H., Javadi, A., Mirtorabi, M. T., Saremi, E., van Loon, J. T., Khosroshahi, H. G. G., …Torki, M. (2023). The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies. VI. The Star Formation History and Dust Production in Andromeda IX. Astrophysical Journal, 948(1), Article 63. https://doi.org/10.3847/1538-4357/acbbc9

• Journal Article Type: Article
• Acceptance Date: Feb 12, 2023
• Publication Date: May 8, 2023
• Deposit Date: Jul 4, 2023
• Journal: ASTROPHYSICAL JOURNAL
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 948
• Issue: 1
• Article Number: 63
• DOI: https://doi.org/10.3847/1538-4357/acbbc9
• Publisher URL: https://iopscience.iop.org/article/10.3847/1538-4357/acbbc9