J/A+A/696/A196 SED modeling of YSOs in the OSFC (Gezer+, 2025)
SED modelling of young stellar objects in the Orion star formation complex.
Gezer I., Marton G., Roquette J., Audard M., Hernandez D., Madarasz M.,
Dionatos O.
<Astron. Astrophys. 696, A196 (2025)>
=2025A&A...696A.196G 2025A&A...696A.196G (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Stars, pre-main sequence ; Photometry, infrared
Keywords: planets and satellites: formation - planets and satellites: general -
stars: formation - stars: pre-main sequence - stars: protostars -
stars: statistics
Abstract:
One of the key tools for understanding the evolution of young stellar
objects (YSOs) is to analyze their spectral energy distributions
(SEDs). As part of the NEMESIS project, we have performed a
large-scale SED fitting analysis of the Orion star formation complex
(OSFC).
We aim to derive key physical parameters, including temperature,
luminosity, mass, and age, for a large sample of sources in the OSFC
using synthetic SED models. Our goal is to establish a statistically
robust characterization of the stellar population and its evolutionary
state across the entire complex.
We utilize a set of new radiative transfer model SEDs that span a
variety of geometries and parameter spaces. These SEDs are fitted to
multi-wavelength photometric data from optical to submillimeter
wavelengths. We conducted SED fitting on a sample of 15396 sources.
Among these, 5062 have at least a reliable W3 (12um) detection at
longer wavelengths, and 63 have sub-millimeter detections in
APEX/SABOCA at 350um or APEX/LABOCA at 870um. The resulting physical
parameters are cross-referenced with stellar evolutionary tracks to
ensure consistency with theoretical predictions.
The derived parameters reveal a diverse stellar population. Sources
placed on the Hertzsprung-Russell diagram show distinct evolutionary
sequences. The results are provided with varying levels of
completeness and reliability, depending on the available data for each
source. The catalog includes quality indicators such as the flux code,
which represents the longest detected wavelength for each source, as
well as Prob_W3 and Prob_W4 values that quantify the reliability of
the AllWISE W3 and W4 detections. All results, including SED fitting
outcomes, uncertainty estimates, and source metadata, are publicly
available in a comprehensive CDS table.
This dataset provides a statistically significant view of the
evolutionary processes within the OSFC. The publicly accessible
dataset offers a valuable resource for future studies on star and
planet formation.
Description:
We performed spectral energy distribution fitting using the models of
Robitaille (2017A&A...600A..11R 2017A&A...600A..11R) for 27879 young stellar objects in
the Orion Star Forming Complex. From this analysis, we successfully
derived physical parameters such as effective temperature and
luminosity for 15396 sources. To estimate stellar masses and ages, we
compared these results with predictions from the PAdova and TRieste
Stellar Evolution Code (PARSEC Bressan et al. (2012MNRAS.427..127B 2012MNRAS.427..127B);
Chen et al. (2014MNRAS.444.2525C 2014MNRAS.444.2525C, 2015MNRAS.452.1068C 2015MNRAS.452.1068C); Tang et al.
(2014MNRAS.445.4287T 2014MNRAS.445.4287T) evolutionary tracks.
The OSFC spans a wide field of view of approximately 564 square
degrees, covering the sky region bounded by 74.2<RA<92 and
-14.1<Dec<17.6.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablee1.dat 335 15396 SED fitting derived parameters for OSFC YSOs
tablee2.dat 928 27879 Photometric data used for SED fitting
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Byte-by-byte Description of file: tablee1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Name Internal ID (IDNNNNN)
9- 25 F17.14 deg RAdeg Right ascension (J2000)
27- 46 F20.16 deg DEdeg Declination (J2000)
48- 54 A7 --- ModelSet Model set identifier (1)
56- 66 A11 --- ModelName Model name
68- 69 I2 --- Ndpt Number of data points used in fitting
71- 90 F20.16 --- chi2 The χ2 per data point (2)
92- 95 I4 --- Nfits Number of fits (3)
97-103 F7.3 mag AV Reddening
105-111 F7.4 Rsun Radius Stellar radius
113-119 F7.1 K Temp Stellar temperature
121-141 F21.16 Lsun Lum Stellar luminosity
143-164 E22.16 Msun DiskMass ? Dust mass contained in the passive disk
166-172 F7.2 AU DiskRmax ? Maximum radius of the passive disk
174-180 F7.3 --- DiskRmin ? Inner radius of the passive disk,
in R_sub unit (1)
182-188 F7.3 --- EnvRmin ? Inner radius of the envelope,
in R_sub unit (1)
190-208 F19.16 deg Incl Viewing angle of the associated SED
210-211 I2 --- AboveMS [-1/1] Above main sequence flag (4)
213-221 A9 --- Stage Physical evolutionary stage of the models (5)
223-231 A9 --- Class Observational class based on IR index (6)
233-254 F22.19 --- SpIndex ?=- Infrared spectral index of the SED (7)
256-257 A2 --- FluxCode Longest detected wavelength code for each sou
259-264 F6.4 --- ProbW3 ? Reliability of AllWISE W3 detection (8)
266-271 F6.4 --- ProbW4 ? Reliability of AllWISE W4 detection (8)
273-308 A36 --- ClosestTrack Closest PARSEC evolutionary track
310-313 F4.2 Msun StarMass Stellar mass
315-335 E21.16 Myr StarAge ? Stellar age
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Note (1): Model set codes from Robitaille (2017A&A...600A..11R 2017A&A...600A..11R):
Geometry Character Glossary (from Robitaille 2017):
Each model set (column model_set) uses a 7-character code:
Letter 1: "s" - The presence of a central protostellar source.
Letter 2: "p"/"-" - The presence or absence of a passive disk.
Letter 3: "p"/"u"/"-" - Envelope type: "p"owerlaw, "u"lrich, or none.
Letter 4: "b"/"-" - The presence or absence of "b"ipolar cavities.
Letter 5: "h"/"s"/"-" - Envelope inner radius: "s"ublimation radius or
larger "h"ole of arbitrary radius.
Letter 6: "m"/"-" - The presence or absence of an ambient "m"edium.
Letter 7: "i" - The presence of "i"nterstellar dust.
------------------------------------------------------------------------------
Model set Ns Components
------------------------------------------------------------------------------
s000s0i 6487 star
sp00s0i 601 star+passive disk; Rinner=Rsub
sp00h0i 650 star+passive disk; variable R_inner
s000smi 5113 star+medium; Rinner=Rsub
sp00smi 572 star+passive disk+medium; Rinner=Rsub
sp00hmi 661 star+passive disk+medium; variable R_inner
s0p0smi 19 star+power-law envelope+medium; Rinner=Rsub
s0p0hmi 46 star+power-law envelope+medium; variable R_inner
s0pbsmi 134 star+power-law envelope+cavity+medium; Rinner=Rsub
s0pbhmi 75 star+power-law env.+cavity+medium; var. R_inner
s0u0smi 148 star+Ulrich envelope+medium; Rinner=Rsub
s0u0hmi 100 star+Ulrich envelope+medium; variable R_inner
s0ubsmi 177 star+Ulrich envelope+cavity+medium; Rinner=Rsub
spu0smi 98 star+passive disk+Ulrich env.+medium; Rinner=Rsub
spu0hmi 109 star+passive disk+Ulrich env.+medium; var. R_inner
spubsmi 94 star+disk+Ulrich env.+cavity+medium; R_sub
spubhmi 151 star+disk+Ulrich env.+cavity+medium; var. R_inner
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Notes:
R_sub is the dust sublimation radius, varies with model.
Ns is the number of sources in Table 1 with this model set.
------------------------------------------------------------------------------
Note (2): For the best-fit model from the most likely model set.
Note (3): With χ2/pt between (χ2min/pt)set and
(χ2min/pt)set + 2 in the most likely model set.
Note (4): Whether model is above the main sequence (MIST tracks) as follows:
-1 = Below
1 = Above
Note (5): Physical evolutionary stage of the models as follows:
Stage 0 = Mcore>0.1M☉, Tstar<3000K (Stage 0)
Stage I = Mcore>0.1M☉, Tstar>3000K (Stage I)
Stage II = Mcore<0.1M☉, disk present (Stage II)
Stage III = No core/disk (Stage III)
= Does not comport with the definition/incomplete
Note (6): Observational class based on IR spectral index (2-25um) as follows:
Class 0 = L350um/Lbol>0.005, no spectral index (Class 0)
Class I = 0.3<a (Class I)
Class II = -1.6<a←0.3 (Class II)
Class III = a←1.6 (Class III)
Flat = -0.3<a<0.3 (Flat)
Note (7): Infrared spectral index of the SED (Dunham et al., 2014,
in Protostars and Planets VI). Calculated between 2 and 25 microns.
Note (8): Probabilities indicating the likelihood of W3 and W4 detections.
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Byte-by-byte Description of file: tablee2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Name Internal ID ((IDNNNNN))
9- 25 F17.14 deg RAdeg Right ascension (J2000)
27- 45 E19.12 deg DEdeg Declination (J2000)
47- 71 F25.18 mJy FBP ? GAIADR3 BP band flux density
73- 96 F24.19 mJy e_FBP ? Error in GAIADR3 BP band flux
98-122 F25.18 mJy FG ? GAIADR3 G band flux density
124-144 E21.16 mJy e_FG ? Error in GAIADR3 G band flux
146-170 F25.18 mJy FRP ? GAIADR3 RP band flux density
172-192 E21.15 mJy e_FRP ? Error in GAIADR3 RP band flux
194-216 F23.17 mJy FJ ? 2MASS J band flux density
218-238 F21.18 mJy e_FJ ? Error in 2MASS J band flux
240-262 F23.17 mJy FH ? 2MASS H band flux density
264-285 F22.18 mJy e_FH ? Error in 2MASS H band flux
287-309 F23.17 mJy FKs ? 2MASS Ks band flux density
311-331 F21.18 mJy e_FKs ? Error in 2MASS Ks band flux
333-355 F23.18 mJy FW1 ? CatWISE W1 3.4um band flux density
357-379 F23.19 mJy e_FW1 ? Error in CatWISE W1 3.4um band flux
381-403 F23.18 mJy FW2 ? CatWISE W2 4.6um band flux density
405-427 F23.19 mJy e_FW2 ? Error in CatWISE W2 4.6um band flux
429-451 F23.17 mJy FW3 ? AllWISE W3 11.6um band flux density
453-474 F22.17 mJy e_FW3 ? Error in AllWISE W3 11.6um band flux
476-497 F22.16 mJy FW4 ? AllWISE W4 22.1um band flux density
499-518 F20.16 mJy e_FW4 ? Error in AllWISE W4 22.1um band flux
520-543 F24.19 mJy FIRAC1 ? Spitzer/IRAC 3.6um band flux density
545-566 F22.19 mJy e_FIRAC1 ? Error in Spitzer/IRAC 3.6um band flux
568-590 F23.18 mJy FIRAC2 ? Spitzer/IRAC 4.5um band flux density
592-612 E21.15 mJy e_FIRAC2 ? Error in Spitzer/IRAC 4.5um band flux
614-637 F24.18 mJy FIRAC3 ? Spitzer/IRAC 5.8um band flux density
639-660 F22.19 mJy e_FIRAC3 ? Error in Spitzer/IRAC 5.8um band flux
662-684 F23.18 mJy FIRAC4 ? Spitzer/IRAC 8.0um band flux density
686-708 F23.19 mJy e_FIRAC4 ? Error in Spitzer/IRAC 8.0um band flux
710-734 F25.18 mJy FMIPS1 ? Spitzer/MIPS 24um band flux density
736-759 F24.18 mJy e_FMIPS1 ? Error in Spitzer/MIPS 24um band flux
761-782 F22.15 mJy FPACS1 ? Herschel/PACS 70um band flux density
784-805 F22.16 mJy e_FPACS1 ? Error in Herschel/PACS 70um band flux
807-828 F22.15 mJy FPACS2 ? Herschel/PACS 100um band flux density
830-850 F21.15 mJy e_FPACS2 ? Error in Herschel/PACS 100um band flux
852-874 F23.15 mJy FPACS3 ? Herschel/PACS 160um band flux density
876-897 F22.15 mJy e_FPACS3 ? Error in Herschel/PACS 160um band flux
899-905 F7.1 mJy F350um ? APEX/SABOCA 350um band flux density
907-913 F7.1 mJy e_F350um ? Error in APEX/SABOCA 350um band flux
915-920 F6.1 mJy F870um ? APEX/LABOCA 870um band flux density
922-928 F7.2 mJy e_F870um ? Error in APEX/LABOCA 870um band flux
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Acknowledgements:
Ilknur Gezer, ilknur.gezer(at)csfk.org
(End) Patricia Vannier [CDS] 09-Apr-2025