Guardado en:
Detalles Bibliográficos
Autores principales: Tu, Zhijun, Wang, Shu, Chen, Xiaodian, Liu, Jifeng
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:https://arxiv.org/abs/2501.16648
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866929689290866688
author Tu, Zhijun
Wang, Shu
Chen, Xiaodian
Liu, Jifeng
author_facet Tu, Zhijun
Wang, Shu
Chen, Xiaodian
Liu, Jifeng
contents We report the spectroscopic identification of three brown dwarf candidates -- o005_s41280, o006_s00089, and o006_s35616 -- discovered in the RUBIES using James Webb Space Telescope (JWST) Near-Infrared Spectrograph (NIRSpec) PRISM/CLEAR spectroscopy. We fit these sources with multiple substellar atmosphere models and present the atmospheric parameters, including effective temperature ($T_\mathrm{eff}$), surface gravity, and other derived properties. The results suggest that o005_s41280 and o006_s35616, with $T_\mathrm{eff}$ in the ranges of 2100--2300 K and 1800--2000 K, are likely L dwarfs, while o006_s00089, with $T_\mathrm{eff} < 1000$ K, is consistent with a late T dwarf classification. The best-fit model spectra provide a reasonable match to the observed spectra. However, distinct residuals exist in the $Y$, $J$, and $H$ bands for the two L dwarf candidates, particularly for o006_s35616. Incorporating the extinction parameter into the fitting process can significantly reduce these residuals. The distance estimates indicate that these candidates are about 2 kpc away. The analysis of the color-color diagram using multiple JWST NIRcam photometry suggests that cooler T dwarfs, such as o006_s00089, overlap with little red dots (LRDs), while hotter L dwarfs, like o005_s41280 and o006_s35616, tend to contaminate the high-redshift galaxy cluster. These findings suggest a brown dwarf contamination rate of approximately 0.1% in extragalactic deep field surveys, with L dwarfs being more frequently detected than cooler T and Y dwarfs.
format Preprint
id arxiv_https___arxiv_org_abs_2501_16648
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Three Brown Dwarfs Masquerading as High-Redshift Galaxies in JWST Observations
Tu, Zhijun
Wang, Shu
Chen, Xiaodian
Liu, Jifeng
Solar and Stellar Astrophysics
We report the spectroscopic identification of three brown dwarf candidates -- o005_s41280, o006_s00089, and o006_s35616 -- discovered in the RUBIES using James Webb Space Telescope (JWST) Near-Infrared Spectrograph (NIRSpec) PRISM/CLEAR spectroscopy. We fit these sources with multiple substellar atmosphere models and present the atmospheric parameters, including effective temperature ($T_\mathrm{eff}$), surface gravity, and other derived properties. The results suggest that o005_s41280 and o006_s35616, with $T_\mathrm{eff}$ in the ranges of 2100--2300 K and 1800--2000 K, are likely L dwarfs, while o006_s00089, with $T_\mathrm{eff} < 1000$ K, is consistent with a late T dwarf classification. The best-fit model spectra provide a reasonable match to the observed spectra. However, distinct residuals exist in the $Y$, $J$, and $H$ bands for the two L dwarf candidates, particularly for o006_s35616. Incorporating the extinction parameter into the fitting process can significantly reduce these residuals. The distance estimates indicate that these candidates are about 2 kpc away. The analysis of the color-color diagram using multiple JWST NIRcam photometry suggests that cooler T dwarfs, such as o006_s00089, overlap with little red dots (LRDs), while hotter L dwarfs, like o005_s41280 and o006_s35616, tend to contaminate the high-redshift galaxy cluster. These findings suggest a brown dwarf contamination rate of approximately 0.1% in extragalactic deep field surveys, with L dwarfs being more frequently detected than cooler T and Y dwarfs.
title Three Brown Dwarfs Masquerading as High-Redshift Galaxies in JWST Observations
topic Solar and Stellar Astrophysics
url https://arxiv.org/abs/2501.16648