J/AJ/168/230 Photometry of substellar candidates in ONC with JWST (Luhman, 2024)
Candidates for substellar members of the Orion Nebula Cluster from JWST/NIRCam.
Luhman K.L.
<Astron. J., 168, 230 (2024)>
=2024AJ....168..230L 2024AJ....168..230L
ADC_Keywords: Stars, brown dwarf ; Clusters, open ; YSOs ; Star Forming Region ;
Photometry, infrared ; MK spectral classification
Keywords: Brown dwarfs ; Initial mass function ; James Webb Space Telescope ;
Star forming regions ; L dwarfs ; Protostars ; Proplyds ;
Circumstellar disks ; Free floating planets ; Protoplanetary disks
Abstract:
In 2022, the James Webb Space Telescope (JWST) obtained 1-5um
images of the center of the Orion Nebula Cluster (ONC). I have
analyzed these data in an attempt to search for substellar members of
the cluster. Using a pair of color-color diagrams, I have identified
>200 brown dwarf candidates that lack spectral classifications. Some
of the candidates could be protostars (either stellar or substellar)
given their very red colors. Based on the age of the ONC and the
photometry predicted by theoretical evolutionary models, the faintest
candidates could have masses of 1-2MJ. This sample of candidates
may prove to be valuable for studying various aspects of young brown
dwarfs, including their mass function and minimum mass. However,
spectroscopy is needed to confirm the membership (via signatures of
youth) and late spectral types of the candidates. Finally, I note that
most of the "Jupiter-mass binary objects" that have been previously
identified with these JWST images are absent from my sample of
candidates because their colors are indicative of reddened background
sources rather than young brown dwarfs, or their photometry is
inadequate for assessing their nature because of very low
signal-to-noise ratios and/or detections in only a few bands.
Description:
The Orion Nebula Cluster (ONC) images from
McCaughrean+ (2023arXiv231003552M 2023arXiv231003552M) were taken with NIRCam on JWST. The
camera simultaneously observes nearly identical areas of sky through
short- and long-wavelength channels (0.7-2.4 and 2.4-5um).
The JWST/NIRCam observations were performed through guaranteed time
observation program 1256 (PI: M. McCaughrean) in September and October
of 2022, as described by McCaughrean+ (2023). The images were obtained
in 12 filters between 1-5um, consisting of F115W, F140M, F162M, F182M,
F187N (Pa-α), and F212N (H2 rovibrational transition) in the
short-wavelength channel and F277W, F300M, F335M, F360M, F444W, and
F470N (H2 rotational transition) in the long-wavelength channel.
The images were taken in a mosaic pattern and, for a given pointing in
a mosaic, the dithered exposures for all selected filters were
collected within a single visit, resulting in a total of 24 visits.
Objects:
------------------------------------------------------------
RA (2000) DE Designation(s)
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05 34 59.99 -05 29 00.0 ONC = NAME Orion Nebula Cluster
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 198 79 Point sources with spectral classifications
table2.dat 162 242 Point source brown dwarf candidates
table3.dat 204 64 Proplyds and other extended sources
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See also:
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
J/AJ/111/846 : Orion HST survey (O'Dell+ 1996)
J/A+A/337/403 : Low-mass stars evolutionary models (Baraffe+ 1998)
J/AJ/117/1375 : Orion Trapezium cluster (Simon+, 1999)
J/ApJ/540/236 : KH photometry of Orion Nebula Cluster (Hillenbrand+, 2000)
J/ApJ/540/1016 : K-band & NICMOS phot. of Trapezium Cluster (Luhman+, 2000)
J/A+A/396/513 : Stellar Rotation in the Orion Nebula Cluster (Herbst+, 2002)
J/ApJ/573/366 : Infrared photometry of Trapezium cluster (Muench+, 2002)
J/ApJS/160/353 : Membership of the Orion nebula population (Getman+, 2005)
J/ApJS/160/319 : COUP: observations and source lists (Getman+, 2005)
J/MNRAS/361/211 : JHK photometry of brown dwarfs in Orion (Lucas+, 2005)
J/AJ/136/2136 : HST/ACS Atlas of Great Orion Nebula proplyds (Ricci+, 2008)
J/A+A/502/883 : I phot.: very low mass ONC stars (Rodriguez-Ledesma+, 2009)
J/A+A/515/A13 : Very low mass objects in ONC (Rodriguez-Ledesma+, 2010)
J/AJ/139/950 : JHKs photometry in ONC (Robberto+, 2010)
J/A+A/534/A10 : HST/NICMOS III imag. Orion Nebula Cluster (Andersen+, 2011)
J/ApJ/748/14 : ONC population data from WFI observations (Da Rio+, 2012)
J/AJ/146/85 : Spect types: 1576 optical stars in ONC (Hillenbrand+, 2013)
J/ApJ/782/8 : Spectroscopy of 104 objects in the ONC (Ingraham+, 2014)
J/ApJ/788/40 : Late-type targets:Taurus, Cha I & Upper Sco (Todorov+, 2014)
J/MNRAS/461/1734 : HAWK-I JHK phot. of the Orion Nebula Cloud (Drass+, 2016)
J/A+A/587/A153 : VISION I. VISTA Orion A Survey (Meingast+, 2016)
J/ApJ/896/79 : HST surv. ONC: H20 1.4um abs. band. I. (Robberto+, 2020)
J/ApJ/896/81 : HST surv. ONC: H2O 1.4um abs. band. III. (Strampelli+, 2020)
J/A+A/657/A131 : Ten new systems with O stars (Maiz Apellaniz+, 2022)
J/ApJ/975/162 : Spec. ONC brown dwarf candidates from JWST (Luhman+, 2024)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- ID Source name from this work
25- 66 A42 --- Name Other source name
68- 76 F9.6 deg RAdeg [83.7/83.9] Right ascension (J2000)
78- 86 F9.6 deg DEdeg [-5.5/-5.3] Declination (J2000)
88- 104 A17 --- SpType Spectral type
106- 110 A5 --- r_SpType Spectral type reference (1)
112- 116 F5.2 mag F115Wmag [16.3/21.3] F115W JWST/NIRCam magnitude
118- 121 F4.2 mag e_F115Wmag [0.02] Error in F115Wmag
123- 127 F5.2 mag F140Mmag [15.9/20.2]? F140M JWST/NIRCam magnitude
129- 132 F4.2 mag e_F140Mmag [0.02]? Error in F140Mmag
134- 138 F5.2 mag F162Mmag [15.7/18.9]? F162M JWST/NIRCam magnitude
140- 143 F4.2 mag e_F162Mmag [0.02]? Error in F162Mmag
145- 149 F5.2 mag F182Mmag [15.6/18.8]? F182M JWST/NIRCam magnitude
151- 154 F4.2 mag e_F182Mmag [0.02]? Error in F182Mmag
156- 160 F5.2 mag F187Nmag [13.5/18.8] F187N JWST/NIRCam magnitude
162- 165 F4.2 mag e_F187Nmag [0.02/0.03] Error in F187Nmag
167- 171 F5.2 mag F277Wmag [15.7/18.6]? F277W JWST/NIRCam magnitude
173- 176 F4.2 mag e_F277Wmag [0.02/0.03]? Error in F277Wmag
178- 182 F5.2 mag F360Mmag [14/18.2]? F360M JWST/NIRCam magnitude
184- 187 F4.2 mag e_F360Mmag [0.02/0.07]? Error in F360Mmag
189- 193 F5.2 mag F444Wmag [13.7/18.2]? F444W JWST/NIRCam magnitude
195- 198 F4.2 mag e_F444Wmag [0.02/0.1]? Error in F444Wmag
--------------------------------------------------------------------------------
Note (1): Reference as follows:
1 = Weights+ (2009MNRAS.392..817W 2009MNRAS.392..817W); 2 occurrences
2 = Ingraham+ 2014 (J/ApJ/782/8); 24 occurrences
3 = Lucas+ (2006MNRAS.373L..60L 2006MNRAS.373L..60L); 6 occurrences
4 = Riddick+ (2007MNRAS.381.1077R 2007MNRAS.381.1077R); 6 occurrences
5 = Slesnick+ (2004ApJ...610.1045S 2004ApJ...610.1045S); 32 occurrences
6 = Luhman+ 2024 (J/ApJ/975/162); 18 occurrences
7 = Hillenbrand 1997 (J/AJ/113/1733); 1 occurrence
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- ID Source name from this work
25- 54 A30 --- Name Other source name
56- 64 F9.6 deg RAdeg [83.7/83.9] Right ascension (J2000)
66- 74 F9.6 deg DEdeg [-5.5/-5.3] Declination (J2000)
76- 80 F5.2 mag F115Wmag [16.7/25.1]? F115W JWST/NIRCam magnitude
82- 85 F4.2 mag e_F115Wmag [0.02/0.13]? Error in F115Wmag
87- 91 F5.2 mag F140Mmag [16.5/25.3] F140M JWST/NIRCam magnitude
93- 96 F4.2 mag e_F140Mmag [0.02/0.18] Error in F140Mmag
98- 102 F5.2 mag F162Mmag [15.6/23.7] F162M JWST/NIRCam magnitude
104- 107 F4.2 mag e_F162Mmag [0.02/0.13] Error in F162Mmag
109- 113 F5.2 mag F182Mmag [15.5/23.4]? F182M JWST/NIRCam magnitude
115- 118 F4.2 mag e_F182Mmag [0.02/0.19]? Error in F182Mmag
120- 124 F5.2 mag F187Nmag [14.6/21.8]? F187N JWST/NIRCam magnitude
126- 129 F4.2 mag e_F187Nmag [0.02/0.18]? Error in F187Nmag
131- 135 F5.2 mag F277Wmag [15.9/23.1]? F277W JWST/NIRCam magnitude
137- 140 F4.2 mag e_F277Wmag [0.02/0.2]? Error in F277Wmag
142- 146 F5.2 mag F360Mmag [14.2/21.2]? F360M JWST/NIRCam magnitude
148- 151 F4.2 mag e_F360Mmag [0.02/0.2]? Error in F360Mmag
153- 157 F5.2 mag F444Wmag [13.7/21.1]? F444W JWST/NIRCam magnitude
159- 162 F4.2 mag e_F444Wmag [0.02/0.2]? Error in F444Wmag
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- ID Source name from this work
25- 69 A45 --- Name Other source name
71- 79 F9.6 deg RAdeg [83.7/83.9] Right ascension (J2000)
81- 89 F9.6 deg DEdeg [-5.5/-5.3] Declination (J2000)
91- 110 A20 --- SpType Spectral type
112- 116 A5 --- r_SpType Spectral type reference (1)
118- 122 F5.2 mag F115Wmag [16.4/21.3]? F115W JWST/NIRCam magnitude
124- 127 F4.2 mag e_F115Wmag [0.02/0.1]? Error in F115Wmag
129- 133 F5.2 mag F140Mmag [15.7/21]? F140M JWST/NIRCam magnitude
135- 138 F4.2 mag e_F140Mmag [0.02/0.03]? Error in F140Mmag
140- 144 F5.2 mag F162Mmag [15.2/22.2]? F162M JWST/NIRCam magnitude
146- 149 F4.2 mag e_F162Mmag [0.02]? Error in F162Mmag
151- 155 F5.2 mag F182Mmag [15.4/20.2]? F182M JWST/NIRCam magnitude
157- 160 F4.2 mag e_F182Mmag [0.02/0.05]? Error in F182Mmag
162- 166 F5.2 mag F187Nmag [13.2/20]? F187N JWST/NIRCam magnitude
168- 171 F4.2 mag e_F187Nmag [0.02/0.1]? Error in F187Nmag
173- 177 F5.2 mag F277Wmag [15.5/18.9]? F277W JWST/NIRCam magnitude
179- 182 F4.2 mag e_F277Wmag [0.02/0.11]? Error in F277Wmag
184- 188 F5.2 mag F360Mmag [14.3/18.2]? F360M JWST/NIRCam magnitude
190- 193 F4.2 mag e_F360Mmag [0.02/0.1]? Error in F360Mmag
195- 199 F5.2 mag F444Wmag [13.9/17.5]? F444W JWST/NIRCam magnitude
201- 204 F4.2 mag e_F444Wmag [0.02/0.1]? Error in F444Wmag
--------------------------------------------------------------------------------
Note (1): Reference as follows:
1 = Weights+ (2009MNRAS.392..817W 2009MNRAS.392..817W); 2 occurrences
2 = Ingraham+ 2014 (J/ApJ/782/8); 2 occurrences
3 = Slesnick+ (2004ApJ...610.1045S 2004ApJ...610.1045S); 11 occurrences
4 = Luhman+ 2024 (J/ApJ/975/162); 2 occurrences
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Nomenclature Notes:
Sources are named <[L2024] ONC JDDD.ddddd+DD.ddddd> in Simbad.
History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 27-Jun-2025