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Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Astrophysics and Astronomy

Florida Institute of Technology

Series

2014

Galaxies: Stellar Content

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Reconstructing The Stellar Mass Distributions Of Galaxies Using S4g Irac 3.6 And 4.5 Μm Images. Ii. The Conversion From Light To Mass, Sharon E. Meidt, Trisha F. Mizusawa Jun 2014

Reconstructing The Stellar Mass Distributions Of Galaxies Using S4g Irac 3.6 And 4.5 Μm Images. Ii. The Conversion From Light To Mass, Sharon E. Meidt, Trisha F. Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

We present a new approach for estimating the 3.6 μm stellar mass-to- light (M/L) ratio Υ3.6 in terms of the [3.6]-[4.5] colors of old stellar populations. Our approach avoids several of the largest sources of uncertainty in existing techniques using population synthesis models. By focusing on mid-IR wavelengths, we gain a virtually dust extinction-free tracer of the old stars, avoiding the need to adopt a dust model to correctly interpret optical or optical/near-IR colors normally leveraged to assign the mass-to-light ratio Υ. By calibrating a new relation between near-IR and mid-IR colors of giant stars observed in GLIMPSE we also …


The Baryonic Tully-Fisher Relationship For S4g Galaxies And The "Condensed" Baryon Fraction Of Galaxies, Dennis Zaritsky, Trisha F. Mizusawa Jun 2014

The Baryonic Tully-Fisher Relationship For S4g Galaxies And The "Condensed" Baryon Fraction Of Galaxies, Dennis Zaritsky, Trisha F. Mizusawa

Aerospace, Physics, and Space Science Faculty Publications

We combine data from the Spitzer Survey for Stellar Structure in Galaxies, a recently calibrated empirical stellar mass estimator from Eskew et al., and an extensive database of H I spectral line profiles to examine the baryonic Tully-Fisher (BTF) relation. We find (1) that the BTF has lower scatter than the classic Tully-Fisher (TF) relation and is better described as a linear relationship, confirming similar previous results, (2) that the inclusion of a radial scale in the BTF decreases the scatter but only modestly, as seen previously for the TF relation, and (3) that the slope of the BTF, which …