J/AJ/170/43 301 L & T-type brown dwarfs archival spectra (Turner+, 2025)
A survey of model fits to brown dwarf spectra through the L-T sequence.
Turner S.K., Stephens D.C., Scoresby C.B., Miller J.A.
<Astron. J., 170, 43 (2025)>
=2025AJ....170...43T 2025AJ....170...43T
ADC_Keywords: Spectroscopy; Optical; Infrared; Stars, brown dwarf;
Stars, L-type; Stars, T-type
Keywords: Brown dwarfs ; L dwarfs ; T dwarfs ; Near IR astronomy ;
IR spectroscopy
Abstract:
We fit archival near-IR spectra of ∼300 brown dwarfs with atmosphere
models from the Sonora and Phoenix groups. Using the parameters of the
best- fit models as estimates for the physical properties of the brown
dwarfs in our sample, we have performed a survey of how brown dwarf
atmospheres evolve with spectral type and temperature. We present the
fit results and observed trends. We find that clouds have a more
significant impact on near-IR spectra than disequilibrium chemistry,
and that silicate clouds influence the near-IR spectrum through the
late T types. We note where current atmosphere models are able to
replicate the data and where the models and data conflict. We also
categorize objects with similar spectral morphologies into families
and discuss possible causes for their unique spectral traits. We
identify two spectral families with morphologies that are likely
indicative of binarity.
Description:
The archival spectra were downloaded from the SpeX Prism Library (SPL;
Burgasser, 2014ASInC..11....7B 2014ASInC..11....7B). Only the most recent spectrum with the
highest resolution was used for each object. This left 301 spectra of
unique sources with spectral types between L0 and T8. These archival
spectra were obtained by multiple groups and published in various
papers from 2004 to 2010.
The SPL spectra were all taken with the SpeX spectrograph at the 3.0m
NASA IR Telescope Facility. The spectra are low resolution
(λ/Δλ∼75-200) and span the near-IR from about 0.8
to 2.5um.
H and Ks magnitudes from the Two Micron All-Sky Survey (2MASS, II/246)
were used to flux calibrate each spectrum.
We found published parallaxes for ∼170 of our 301 sample objects on
the open-source SIMPLE Database. An additional ∼70 objects had
published parallaxes listed on SIMBAD. For objects with multiple
published parallaxes, the one with the smallest uncertainty was used.
The majority of these parallaxes came from Gaia EDR3(I/350) or
Best+2020 (J/AJ/159/257).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table9.dat 129 301 List of all 301 archival spectra used in this project
--------------------------------------------------------------------------------
See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)
J/AJ/126/2487 : T dwarfs in the southern hemisphere (Burgasser+, 2003)
J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)
J/AJ/127/2856 : Brown dwarfs in the 2MASS Survey (Burgasser+, 2004)
J/AJ/127/3553 : JHK phot. and spectroscopy for L and T dwarfs (Knapp+, 2004)
J/ApJ/637/1067 : Near-IR spectral class. of T dwarfs (Burgasser+, 2006)
J/AJ/131/2722 : New L and T dwarfs from the SDSS (Chiu+, 2006)
J/PASP/118/659 : RI photometry of 2MASS late M and L dwarfs (Liebert+, 2006)
J/AJ/133/439 : Luminosity function of M7-L8 ultracool dwarfs (Cruz+, 2007)
J/AJ/134/1162 : 11 new T dwarfs in 2MASS (Looper+, 2007)
J/ApJ/689/1295 : Li test implications for brown dwarfs (Kirkpatrick+, 2008)
J/ApJ/676/1281 : L and T dwarfs in 2MASS/SDSS (Metchev+, 2008)
J/MNRAS/383/831 : New DENIS nearby L and late-M dwarfs (Phan-Bao+, 2008)
J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)
J/A+A/497/619 : New ultra-cool dwarfs from SDSS and 2MASS (Zhang+, 2009)
J/ApJ/710/1142 : SpeX spectro. of low mass binaries. I. (Burgasser+, 2010)
J/ApJS/190/100 : NIR proper motion survey using 2MASS (Kirkpatrick+, 2010)
J/AJ/139/1808 : Colors and kinematics of SDSS L dwarfs (Schmidt+, 2010)
J/ApJS/201/19 : Hawaii Infrared Parallax Program. I. (Dupuy+, 2012)
J/ApJ/752/56 : BDKP. III. Parallaxes for 70 ultracool dwarfs (Faherty+, 2012)
J/ApJ/746/23 : Radio observations of ultracool dwarf stars (McLean+, 2012)
J/MNRAS/428/2824 : Rapid optical variability in ultracool dwarfs (Koen, 2013)
J/ApJ/794/143 : New SpeX Observations of M7-L6 Dwarfs (Bardalez+, 2014)
J/AJ/147/34 : SpeX library of L-type dwarfs (Schneider+, 2014)
J/ApJS/219/33 : BANYAN. VII. Candidate YMG members from BASS (Gagne+, 2015)
J/MNRAS/449/3651 : L and T dwarfs from UKIDSS LAS (Marocco+, 2015)
J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)
J/ApJ/833/96 : Hawaii IR parallax program. II. Ultracool dwarfs (Liu+, 2016)
J/ApJS/231/15 : Astrometric monitor. of ultracool dwarf binaries (Dupuy+, 2017)
J/AJ/155/34 : Analysis of the NIR spectra of neighboring L dwarfs (Cruz+, 2018)
J/MNRAS/481/3548 : Parallaxes of Southern Extremely Cool objects (Smart+, 2018)
J/ApJ/883/205 : Ultracool SpeXtroscopic surv. I. M7-L5 sample (Bardalez+, 2019)
J/AJ/157/101 : Cloud Atlas: HST/WFC3 NIR spectral library (Manjavacas+, 2019)
J/AJ/159/257 : Hawaii IR parallax prog. IV. L0-T8 BDs with UKIRT (Best+, 2020)
J/AJ/160/63 : IR spectra of 5 brown dwarfs with Gemini North IRS (Miles+, 2020)
J/AJ/161/42 : Volume-limited samp of cool dwarfs. I. L0-T8 dwarfs (Best+, 2021)
J/ApJS/253/7 : Full-sky census of brown dwarfs within 20pc (Kirkpatrick+, 2021)
J/MNRAS/513/5701 : Silicate clouds in ultracool dwarfs (Suarez+, 2022)
J/ApJ/943/L16 : Keck/NIRES sp. of CWISE J050626.96+073842.4 (Schneider+, 2023)
http://doi.org/10.5281/zenodo.15314197 : Zenodo repository from this work
Byte-by-byte Description of file: table9.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 28 A28 --- Name Object name
30- 52 A23 --- OName Alternate name
54- 66 A13 --- OType Optical spectral type (1)
68- 84 A17 --- IRType Near-IR spectral type (1)
86- 91 F6.3 mag Jmag [12.4/18.3] 2MASS J Vega magnitude
93- 98 F6.3 mag Hmag [11.5/16.7] 2MASS H Vega magnitude
100- 105 F6.3 mag Ksmag [11.0/17.1] 2MASS Ks Vega magnitude
107- 117 F11.7 --- plx [13.5/205.5]? Parallax, SIMPLE
Database (see references)
119- 129 A11 --- Sources Sources (2)
--------------------------------------------------------------------------------
Note (1): A single colon indicates an uncertainty of 1.5 spectral types or less,
while a double colon indicates an uncertainty greater than 1.5 spectral types.
Note (2): References as follows:
1 = Albert+2011 (2011AJ....141..203A 2011AJ....141..203A)
2 = Allers+2013 (2013ApJ...772...79A 2013ApJ...772...79A)
3 = Bardalez Gagliuffi+2014 (J/ApJ/794/143)
4 = Best+2021 (J/AJ/161/42)
5 = Best+2021 (J/AJ/161/42)
6 = Burgasser+2006 (2006AJ....131.1007B 2006AJ....131.1007B)
7 = Burgasser+2003b (J/AJ/126/2487)
8 = Burgasser+2003a (2003ApJ...594..510B 2003ApJ...594..510B)
9 = Burgasser+2006 (J/ApJ/637/1067)
10 = Burgasser+2007 (2007ApJ...658..557B 2007ApJ...658..557B)
11 = Burgasser+2008b (2008ApJ...674..451B 2008ApJ...674..451B)
12 = Burgasser+2009 (2009AJ....138.1563B 2009AJ....138.1563B)
13 = Burgasser+2010 (J/ApJ/710/1142)
14 = Burgasser+2004 (J/AJ/127/2856)
15 = Burgasser+2008a (2008ApJ...681..579B 2008ApJ...681..579B)
16 = Burgasser+2011 (2011AJ....141...70B 2011AJ....141...70B)
17 = Burgasser+2007 (2007ApJ...659..655B 2007ApJ...659..655B)
18 = Chiu+2006 (J/AJ/131/2722)
19 = Cruz+2004 (2004ApJ...604L..61C 2004ApJ...604L..61C)
20 = Cruz+2003 (J/AJ/126/2421)
21 = Cruz+2007 (J/AJ/133/439)
22 = Cruz+2009 (2009AJ....137.3345C 2009AJ....137.3345C)
23 = Cruz+2018 (J/AJ/155/34)
24 = Cushing+2005 (2005ApJ...623.1115C 2005ApJ...623.1115C)
25 = Dahn+2002 (2002AJ....124.1170D 2002AJ....124.1170D)
26 = Dupuy+2012 (J/ApJS/201/19)
27 = Dupuy+2017 (J/ApJS/231/15)
28 = Faherty+2010 (2010AJ....139..176F 2010AJ....139..176F)
29 = Faherty+2012 (J/ApJ/752/56)
30 = Faherty+2013 (2013AJ....145....2F 2013AJ....145....2F)
31 = Faherty+2016 (J/ApJS/225/10)
32 = Fan+2000 (2000AJ....119..928F 2000AJ....119..928F)
33 = Gagne+2015 (J/ApJS/219/33)
34 = Gaia Collaboration+2016 (I/337)
= Gaia Collaboration+2018 (I/345)
35 = Brown+2021 (2021A&A...650C...3G 2021A&A...650C...3G)
36 = Gauza+2019 (2019MNRAS.487.1149G 2019MNRAS.487.1149G)
37 = Geballe+2002 (2002ApJ...564..466G 2002ApJ...564..466G)
38 = Gelino+2010 (2010AJ....140..110G 2010AJ....140..110G)
39 = Gizis+2000 (2000AJ....120.1085G 2000AJ....120.1085G)
40 = Gizis+2001 (2001AJ....121.2185G 2001AJ....121.2185G)
41 = Gizis+2002 (2002ApJ...575..484G 2002ApJ...575..484G)
42 = Hawley+2002 (J/AJ/123/3409)
43 = Kendall+2004 (2004A&A...416L..17K 2004A&A...416L..17K)
44 = Kirkpatrick+2000 (2000AJ....120..447K 2000AJ....120..447K)
45 = Kirkpatrick+2001 (2001AJ....121.3235K 2001AJ....121.3235K)
46 = Kirkpatrick+2008 (J/ApJS/190/100)
47 = Kirkpatrick+2010 (J/AJ/127/3553)
48 = Kirkpatrick+1999 (2003AJ....125..343L 2003AJ....125..343L)
49 = Kirkpatrick+2006 (J/PASP/118/659)
50 = Knapp+2004 (J/AJ/127/3553)
51 = Liebert+2003 (2003AJ....125..343L 2003AJ....125..343L)
52 = Liebert+2006 (J/PASP/118/659)
53 = Liebert+2007 (2007ApJ...655..522L 2007ApJ...655..522L)
54 = Liu+2013 (2013ApJ...777L..20L 2013ApJ...777L..20L)
55 = Liu+2016 (J/ApJ/833/96)
56 = Looper+2007 (J/AJ/134/1162)
57 = Looper+2008a (2008ApJ...685.1183L 2008ApJ...685.1183L)
58 = Looper+2008b (2008ApJ...686..528L 2008ApJ...686..528L)
59 = Luhman+2007 (2007ApJ...654..570L 2007ApJ...654..570L)
60 = Manjavacas+2019 (J/AJ/157/101)
61 = Marocco+2013 (2013AJ....146..161M 2013AJ....146..161M)
62 = Marocco+2015 (J/MNRAS/449/3651)
63 = McElwain+2006 (2006AJ....132.2074M 2006AJ....132.2074M)
64 = Metchev+2008 (J/ApJ/676/1281)
65 = Phan-Bao+2008 (J/MNRAS/383/831)
66 = Pineda+2016 (2016ApJ...826...73P 2016ApJ...826...73P)
67 = Reid+2006 (2006ApJ...639.1114R 2006ApJ...639.1114R)
68 = Reid+2008 (J/AJ/136/1290)
69 = Schmidt+2010b (J/AJ/139/1808)
70 = Schneider+2014 (J/AJ/147/34)
71 = Sheppard+2009 (2009AJ....137..304S 2009AJ....137..304S)
72 = Siegler+2007 (2007PhDT........11S 2007PhDT........11S)
73 = Smart+2013 (2013MNRAS.433.2054S 2013MNRAS.433.2054S)
74 = Smart+2018 (J/MNRAS/481/3548)
75 = Tinney+2003 (2003AJ....126..975T 2003AJ....126..975T)
76 = Tinney+2014 (2014ApJ...796...39T 2014ApJ...796...39T)
77 = Vrba+2004 (2004AJ....127.2948V 2004AJ....127.2948V)
78 = Wilson+2001 (2001AJ....122.1989W 2001AJ....122.1989W)
79 = Wilson+2003 (2003IAUS..211..197W 2003IAUS..211..197W)
80 = Zhang+2009 (J/A+A/497/619)
81 = Stumpf+2009 (2009AIPC.1094..561S 2009AIPC.1094..561S)
82 = Bardalez Gagliuffi+2019 (J/ApJ/883/205)
83 = Scholz+2002 (2002MNRAS.336L..49S 2002MNRAS.336L..49S)
84 = Schmidt+2010a (2010AJ....139.1045S 2010AJ....139.1045S)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 17-Apr-2026