Simulating Brown Dwarf Observations for Various Mass Functions, Birthrates, and Low-mass Cutoffs

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Raghu, Yadukrishna, Kirkpatrick, J. Davy, Marocco, Federico, Gelino, Christopher R., Gagliuffi, Daniella C. Bardalez, Faherty, Jacqueline K., Schurr, Steven D., Schneider, Adam C., Meisner, Aaron M., Kuchner, Marc J., Brooks, Hunter, Grigorian, Jake, Worlds, The Backyard, :, Collaboration, Planet 9
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866917693966254080
author Raghu, Yadukrishna
Kirkpatrick, J. Davy
Marocco, Federico
Gelino, Christopher R.
Gagliuffi, Daniella C. Bardalez
Faherty, Jacqueline K.
Schurr, Steven D.
Schneider, Adam C.
Meisner, Aaron M.
Kuchner, Marc J.
Brooks, Hunter
Grigorian, Jake
Worlds, The Backyard
:
Collaboration, Planet 9
author_facet Raghu, Yadukrishna
Kirkpatrick, J. Davy
Marocco, Federico
Gelino, Christopher R.
Gagliuffi, Daniella C. Bardalez
Faherty, Jacqueline K.
Schurr, Steven D.
Schneider, Adam C.
Meisner, Aaron M.
Kuchner, Marc J.
Brooks, Hunter
Grigorian, Jake
Worlds, The Backyard
:
Collaboration, Planet 9
contents After decades of brown dwarf discovery and follow-up, we can now infer the functional form of the mass distribution within 20 parsecs, which serves as a constraint on star formation theory at the lowest masses. Unlike objects on the main sequence that have a clear luminosity-to-mass correlation, brown dwarfs lack a correlation between an observable parameter (luminosity, spectral type, or color) and mass. A measurement of the brown dwarf mass function must therefore be procured through proxy measurements and theoretical models. We utilize various assumed forms of the mass function, together with a variety of birthrate functions, low-mass cutoffs, and theoretical evolutionary models, to build predicted forms of the effective temperature distribution. We then determine the best fit of the observed effective temperature distribution to these predictions, which in turn reveals the most likely mass function. We find that a simple power law ($dN/dM \propto M^{-α}$) with $α\approx 0.5$ is optimal. Additionally, we conclude that the low-mass cutoff for star formation is $\lesssim0.005M_{\odot}$. We corroborate the findings of Burgasser (2004) which state that the birthrate has a far lesser impact than the mass function on the form of the temperature distribution, but we note that our alternate birthrates tend to favor slightly smaller values of $α$ than the constant birthrate. Our code for simulating these distributions is publicly available. As another use case for this code, we present findings on the width and location of the subdwarf temperature gap by simulating distributions of very old (8-10 Gyr) brown dwarfs.
format Preprint
id arxiv_https___arxiv_org_abs_2406_09690
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Simulating Brown Dwarf Observations for Various Mass Functions, Birthrates, and Low-mass Cutoffs
Raghu, Yadukrishna
Kirkpatrick, J. Davy
Marocco, Federico
Gelino, Christopher R.
Gagliuffi, Daniella C. Bardalez
Faherty, Jacqueline K.
Schurr, Steven D.
Schneider, Adam C.
Meisner, Aaron M.
Kuchner, Marc J.
Brooks, Hunter
Grigorian, Jake
Worlds, The Backyard
:
Collaboration, Planet 9
Solar and Stellar Astrophysics
Earth and Planetary Astrophysics
After decades of brown dwarf discovery and follow-up, we can now infer the functional form of the mass distribution within 20 parsecs, which serves as a constraint on star formation theory at the lowest masses. Unlike objects on the main sequence that have a clear luminosity-to-mass correlation, brown dwarfs lack a correlation between an observable parameter (luminosity, spectral type, or color) and mass. A measurement of the brown dwarf mass function must therefore be procured through proxy measurements and theoretical models. We utilize various assumed forms of the mass function, together with a variety of birthrate functions, low-mass cutoffs, and theoretical evolutionary models, to build predicted forms of the effective temperature distribution. We then determine the best fit of the observed effective temperature distribution to these predictions, which in turn reveals the most likely mass function. We find that a simple power law ($dN/dM \propto M^{-α}$) with $α\approx 0.5$ is optimal. Additionally, we conclude that the low-mass cutoff for star formation is $\lesssim0.005M_{\odot}$. We corroborate the findings of Burgasser (2004) which state that the birthrate has a far lesser impact than the mass function on the form of the temperature distribution, but we note that our alternate birthrates tend to favor slightly smaller values of $α$ than the constant birthrate. Our code for simulating these distributions is publicly available. As another use case for this code, we present findings on the width and location of the subdwarf temperature gap by simulating distributions of very old (8-10 Gyr) brown dwarfs.
title Simulating Brown Dwarf Observations for Various Mass Functions, Birthrates, and Low-mass Cutoffs
topic Solar and Stellar Astrophysics
Earth and Planetary Astrophysics
url https://arxiv.org/abs/2406.09690