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This content will become publicly available on January 3, 2026

Title: Mapping Dust Attenuation in Dusty Dwarf Galaxies
Interstellar dust present in the interstellar medium creates a challenge when investigating galactic properties due to the reddening and scattering - i.e., attenuation - of light. Attenuation laws have been found to be a critical uncertainty in all astronomy, as it has been shown to vary across different sightlines, leading to different attenuation curves throughout the literature. This is especially true for low mass disk galaxies, where dust attenuation and its role in constraining galaxy spectral energy distributions (SEDs) remain poorly understood. Spatially resolved dust attenuation in these dwarf galaxies will be investigated using the technique of overlapping - occulting - galaxy pairs: the practice of calculating dust using the light lost in the galaxy pair overlap when a foreground galaxy overlaps a more distant background galaxy. In an occulting galaxy pair, the latter backlights the dusty structures in the nearer foreground galaxy. Hubble Space Telescope (HST) broadband imaging from the optical to infrared of multiple nearby dwarf (z < 0.09; M* < 1010 M⊙) occulters. With the high resolution of HST, highly accurate dust extinction maps will be constructed pixel-by-pixel among the scale of molecular clouds in the overlap region of the foreground galaxy with hundreds of independent lines-of-sight. Mapped dust attenuation in dwarf galaxies will provide vital information that is needed to investigate their properties such as SEDs, star formation, and their dust physics of the ISM.  more » « less
Award ID(s):
2319428
PAR ID:
10645131
Author(s) / Creator(s):
;
Publisher / Repository:
volume 245 of American Astronomical Society Meeting Abstracts, 307.08, January 2025
Date Published:
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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