Measurement of the Half-Light Radius for the Tucana Dwarf Spheroidal Galaxy

2025/12/12 by Pei-Jun Huang, Huang, Pei-Jun, Ian Dell’Antonio +7
Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Scientific Research and Discoveries

paper · pdf · doi:10.48550/arxiv.2512.12027

Abstract

We present a new measurement of the half-light radius of the Tucana Dwarf galaxy, based on the combination of wider, deeper imaging conducted as part of the Local Volume Complete Cluster Survey (LoVoCCS) and HST archival images. We obtain a stellar density profile within the Tucana Dwarf field based on elliptical fitting. After background subtraction, we fit a Sérsic profile to the density profile to obtain the half-light radius. We measure the half-light radius to be 0.89_-0.02^+0.06 arcmin, corresponding to a value of R_e = 225.7_-5.5^+14.4 pc (95% CL). Given the wider-field observations from LoVoCCS used in this analysis, our measurement of the half-light radius represents a ∼ 10 % increased value from the previous results.

Citations

• Stellar Metallicities and Gradients in the Isolated, Quenched Low-Mass Galaxy Tucana
• An Overview of the LSST Image Processing Pipelines
• CCD photometry of the Tucana dwarf galaxy
• The Tucana dwarf galaxy

Related

• CCD photometry of the Tucana dwarf galaxy
• The Tucana dwarf galaxy
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