Dust Production by AGB stars in the NGC 6822 Galaxy

Asymptotic Giant Branch (AGB) stars and Long-Period Variables (LPVs) represent the final evolutionary stages of low- to intermediate-mass (0.8–8 M⊙) stars and play a crucial role in enriching the interstellar medium (ISM) with metals and dust, thereby influencing the chemical evolution of galaxies. In this study, AGB stars and LPVs in the dwarf irregular galaxy NGC 6822 were investigated using publicly available multi-wavelength photometric data spanning the near- to mid-infrared regime, including observations from JWST, Spitzer, and UKIRT. Candidate AGBs and LPVs were identified through crossmatching with available online catalogs, and a consolidated catalog of their multi-band photometry was compiled. The spectral energy distributions (SEDs) of these sources were modeled using the DUSTY and SEDust codes to derive mass-loss rates and other dust-related parameters. Both oxygen-rich (O-type) and carbon-rich (C-type) AGB and LPV populations were analyzed, and their combined contribution to the chemical enrichment of NGC 6822 was quantified, yielding a total mass-loss rate of 2.4 × 10−4 M⊙ yr−1 for the modeled sample. Correlations between key parameters, such as optical depth and bolometric correction, were further examined to estimate mass-loss rates for AGBs and LPVs not modeled due to incomplete photometric coverage.