J/ApJ/908/49 361 Hertzsprung-Russell diagram in Orion (Fang+, 2021)
An Improved Hertzsprung-Russell Diagram for the Orion Trapezium Cluster.
Fang M., Kim J.S., Pascucci I., Apai D.
<Astrophys. J., 908, 49 (2021)>
=2021ApJ...908...49F 2021ApJ...908...49F
ADC_Keywords: Stars, pre-main sequence; Spectral types; Extinction; Optical
Keywords: Pre-main sequence stars ; Stellar accretion disks ;
Protoplanetary disks ; Hertzsprung Russell diagram ; Stellar
classification
Abstract:
We present a study of the Trapezium cluster in Orion. We analyze flux-
calibrated Very Large Telescope/Multi-Unit Spectroscopic Explorer
spectra of 361 stars to simultaneously measure the spectral types,
reddening, and the optical veiling due to accretion. We find that the
extinction law from Cardelli et al. with a total-to-selective
extinction value of RV=5.5 is more suitable for this cluster. For 68%
of the sample the new spectral types are consistent with literature
spectral types within two subclasses but, as expected, we derive
systematically later types than the literature by one to two
subclasses for the sources with significant accretion levels. Here we
present an improved Hertzsprung-Russell (H-R) diagram of the Trapezium
cluster, in which the contamination by optical veiling on spectral
types and stellar luminosities has been properly removed. A comparison
of the locations of the stars in the H-R diagram with the non-magnetic
and magnetic pre-main-sequence evolutionary tracks indicates an age of
1-2Myr. The magnetic pre-main-sequence evolutionary tracks can better
explain the luminosities of the low-mass stars. In the H-R diagram,
the cluster exhibits a large luminosity spread
(σ(LogL*/L☉)∼0.3). By collecting a sample of 14
clusters/groups with different ages, we find that the luminosity
spread tends to be constant (σ(LogL*/L☉)∼0.2-0.25) after
2Myr, which suggests that age spread is not the main cause of the
luminosity spread. There are ∼0.1dex larger luminosity spreads for the
younger clusters, e.g., the Trapezium cluster, than the older
clusters, which can be explained by the starspots, accretion history,
and circumstellar disk orientations.
Description:
The data were taken with MUSE, which is the second-generation Integral
Field Unit (IFU) mounted on the VLT at the Nasmyth B focus of the
Yepun (the VLT UT4 telescope) in Paranal, Chile. The observations were
carried out during the first commissioning run, under photometric
conditions with the Differential Image Motion Monitor seeing ranging
from 067 to 125, and airmass changing from 1.067 to 1.483. The
observations were performed in Wide Field Mode with a field of view
covering 1x1' and a pixel size of 02x02. A total of 30 pointings over
a six-by-five mosaic are taken to cover the Orion Trapezium Cluster
with a field of 59x49.
Objects:
-----------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------
05 35 16.80 -05 23 23.9 Orion = 3C 145
-----------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 184 361 List of sources, their Spectral types and stellar
luminosities
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See also:
II/62 : Catalogue of Extinction Data (Neckel+, 1980)
III/150 : Perkins Revised MK Types for the Cooler Stars (Keenan+ 1989)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AJ/113/1733 : Orion Nebula Cluster population (Hillenbrand 1997)
J/A+AS/123/329 : New weak-line T Tauri stars in Lupus (Krautter+ 1997)
J/A+A/326/211 : T Tau Stars (Wichmann+, 1997)
J/AJ/116/1816 : JHKLMNOPQ photometry in Orion cluster (Hillenbrand+, 1998)
J/A+A/333/619 : Upper Scorpius OB association Li survey (Preibisch+ 1998)
J/ApJ/525/466 : Young low-mass stars & brown dwarfs in IC 348 (Luhman+, 1999)
J/ApJ/540/236 : KH photometry of Orion Nebula Cluster (Hillenbrand+, 2000)
J/ApJ/540/1016 : K-band & NICMOS photometry Trapezium Cluster (Luhman+, 2000)
J/A+A/396/513 : Stellar Rotation in the Orion Nebula Cluster (Herbst+, 2002)
J/AJ/124/1670 : Post-T Tauri Stars in Sco-Cen Association (Mamajek+, 2002)
J/ApJ/573/366 : Infrared photometry of Trapezium cluster (Muench+, 2002)
J/ApJ/593/1093 : IC 348 membership (Luhman+, 2003)
J/ApJ/601/979 : vsini of Orion low-mass stars (Wolff+, 2004)
J/other/ARA+A/42.685 : Young stars near the Sun (Zuckerman+, 2004)
J/AJ/130/1805 : Hα emission stars in NGC 2362 (Dahm+, 2005)
J/AJ/129/1534 : Mid-IR photometry in the Orion Nebula (Robberto+, 2005)
J/AJ/130/1763 : 11.7µm point sources in Orion (Smith+, 2005)
J/ApJ/645/676 : Spatial distribution brown dwarfs in Taurus (Luhman+, 2006)
J/AJ/132/866 : New M dwarfs in solar neighborhood (Riaz+, 2006)
J/A+A/460/695 : Search Associations Containing Young stars (Torres+, 2006)
J/MNRAS/376/580 : Cousins RI photometry of NGC 2169 (Jeffries+, 2007)
J/ApJS/173/104 : Stellar population in Chamaeleon I (Luhman, 2007)
J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)
J/AJ/136/2136 : HST/ACS Atlas of Great Orion Nebula proplyds (Ricci+, 2008)
J/A+A/488/167 : Low-mass stars in σ Ori and λ Ori (Sacco+, 2008)
J/A+A/504/461 : YSOs in L1630N and L1641 (Fang+, 2009)
J/ApJ/722/1092 : Optical photometry of the ONC. II. (Da Rio+, 2010)
J/A+A/521/A18 : Blue stars with disk photometry in NGC6611 (Guarcello+, 2010)
J/AJ/139/950 : JHKs photometry in ONC (Robberto+, 2010)
J/ApJ/724/835 : The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)
J/ApJ/731/8 : Multiple star formation in Taurus-Auriga (Kraus+, 2011)
J/ApJ/748/14 : ONC population data from WFI observations (Da Rio+, 2012)
J/AJ/144/192 : Spitzer survey of Orion A & B. I. YSO cat. (Megeath+, 2012)
J/ApJ/745/119 : Close companions to young stars I. ChaI & Tau (Nguyen+, 2012)
J/A+A/548/A56 : X-shooter spectra 12 young stellar objects (Rigliaco+, 2012)
J/ApJS/207/5 : YSOs in LDN 1641 with Hectochelle spectra (Fang+, 2013)
J/AJ/146/85 : Spectral types 1576 optical stars in ONC (Hillenbrand+, 2013)
J/A+A/551/A107 : X-shooter spectra of 24 young stellar objects (Manara+, 2013)
J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)
J/A+A/561/A2 : 36 accreting YSOs emission lines (Alcala+, 2014)
J/ApJ/786/97 : Photospheric properties of T Tauri stars (Herczeg+, 2014)
J/ApJ/794/36 : σ Orionis cluster stellar population (Hernandez+, 2014)
J/A+A/593/A7 : NH and AV Towards YSOs in the ONC (Hasenberger+, 2016)
J/ApJ/831/125 : ALMA 887um obs. of ChaI star-forming region (Pascucci+, 2016)
J/MNRAS/461/794 : Scorpius-Centaurus K-Type Stars (Pecaut+, 2016)
J/A+A/600/A20 : Lupus YSOs X-shooter spectroscopy (Alcala+, 2017)
J/AJ/153/188 : Spectroscopy of foreground population in OrionA (Fang+, 2017)
J/ApJ/834/142 : Gould's Belt Distances Survey. II. OMC (Kounkel+, 2017)
J/ApJ/838/150 : The Taurus-Auriga ecosystem. I. (Kraus+, 2017)
J/AJ/153/46 : Spectroscopy of candidate members in Taurus (Luhman+, 2017)
J/A+A/605/A86 : Pre-main sequence stars VLT/X-Shooter spectra (Manara+, 2017)
J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)
J/AJ/156/76 : New young stars and brown dwarfs in Upper Sco (Luhman+, 2018)
J/A+A/609/A10 : NGC2264 structure and star formation history (Venuti+, 2018)
J/AJ/157/85 : The CIDA Variability Survey of Orion OB1 II. (Briceno+, 2019)
J/A+A/632/A46 : TW Hydrae association with X-shooter (Venuti+, 2019)
J/ApJ/904/146 : Young stars North the America & Pelican Nebulae (Fang+, 2020)
J/ApJ/893/67 : Smoothed amplitudes from Kepler K2 & TESS phot (Morris, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- ID [1/361] Internal identifier
5- 6 I2 h RAh [5/5] Hour of Right Ascension (J2000)
8- 9 I2 min RAm [35/35] Minute of Right Ascension (J2000)
11- 15 F5.2 s RAs [5/29] Second of Right Ascension (J2000)
17 A1 --- DE- [-] Sign of the Declination (J2000)
18- 19 I2 deg DEd [5/5] Degree of Declination (J2000)
21- 22 I2 arcmin DEm [21/26] Arcminute of Declination (J2000)
24- 27 F4.1 arcsec DEs Arcsecond of Declination (J2000)
29- 32 A4 --- SpT1 Spectral type from method 1 (1)
34- 39 F6.3 Lsun logL*-1 [-2.15/1.68] log stellar luminosity from
method 1 (1)
41- 44 F4.2 mag AV-1 [0/6.37] V band extinction from method 1 (1)
46- 49 F4.2 --- r7465-1 [0/4.8] Veiling at 7465A from method 1 (1)
51- 54 A4 --- SpT-2 Spectral type from method 2 (2)
56- 61 F6.3 Lsun logL*-2 [-2.01/1.68] log stellar luminosity from
method 2 (2)
63- 66 F4.2 mag AV-2 [0/6.58] V band extinction from method 2 (2)
68- 71 F4.2 --- r7465-2 [0/4.44] Veiling at 7465A from method 2 (2)
73- 76 A4 --- SpT-3 Spectral type from method 3 (3)
78- 83 F6.3 Lsun logL*-3 [-2.07/1.79] log stellar luminosity from
method 3 (3)
85- 88 F4.2 mag AV-3 [0/7.79] V band extinction from method 3 (3)
90- 93 F4.2 --- r7465-3 [0/4.78] Veiling at 7465A from method 3 (3)
95- 98 A4 --- SpT-4 Spectral type from method 4 (4)
100-105 F6.3 Lsun logL*-4log [-1.97/1.79] stellar luminosity from
method 4 (4)
107-110 F4.2 mag AV-4 [0/7.85] V band extinction from method 4 (4)
112-115 F4.2 --- r7465-4 [0/4.43] Veiling at 7465A from method 4 (4)
117-120 I4 --- Star [265/9320]? Hillenbrand+, 2013, J/AJ/146/85
identifier
122-184 A63 --- SpT Literature spectral type (5)
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Note (1): Fitting the MUSE spectra using the extinction law from
Cardeli+, 1989ApJ...345..245C 1989ApJ...345..245C with RV=3.1 and a constant accretion
continuum spectrum.
Note (2): Fitting the MUSE spectra using the extinction law from
Cardeli+, 1989ApJ...345..245C 1989ApJ...345..245C with RV=3.1 and a TBB=7000K
accretion continuum spectrum.
Note (3): Fitting the MUSE spectra using the extinction law from
Cardeli+, 1989ApJ...345..245C 1989ApJ...345..245C with RV=5.5 and a constant accretion
continuum spectrum.
Note (4): Fitting the MUSE spectra using the extinction law from
Cardeli+, 1989ApJ...345..245C 1989ApJ...345..245C with RV=5.5 and a TBB=7000K
accretion continuum spectrum.
Note (5): All the spectral types are collected from
H13 = Hillenbrand+, 2013, J/AJ/146/85
H97 = Hillenbrand+, 1997, J/AJ/113/1733
Luc01 = Lucas+, 2001MNRAS.326..695L 2001MNRAS.326..695L
RRL = Riddick+, 2007MNRAS.381.1077R 2007MNRAS.381.1077R
WLR = Weights+, 2009MNRAS.392..817W 2009MNRAS.392..817W
WSH = Wolff+, 2004, J/ApJ/601/979
vA = van Altena+, 1988AJ.....95.1744V 1988AJ.....95.1744V
J = Johnson+, 1965ApJ...142..964J 1965ApJ...142..964J
W = Walker+, 1983ApJ...271..642W 1983ApJ...271..642W
CK = Cohen & Kuhin, 1979ApJS...41..743C 1979ApJS...41..743C
Ste = H C. Stempels 2008, private communication, high
dispersion spectra, taken from Hillenbrand+, 2013, J/AJ/146/85
SHC-ir = infrared spectral types from
Slesnick+, 2004ApJ...610.1045S 2004ApJ...610.1045S
Sam = A.E. Samuel 1993 unpublished PhD thesis, taken
from Hillenbrand+, 2013, J/AJ/146/85
E = Edwards+, 1993AJ....106..372E 1993AJ....106..372E
P = Prosser & Stauffer 1995, private communication,
taken from Hillenbrand+, 2013, J/AJ/146/85
HT = Herbig & Terndrup, 1986ApJ...307..609H 1986ApJ...307..609H
or reference therein;
Ham = C. Hamilton 1994 unpublished masters thesis,
taken from Hillenbrand+, 2013, J/AJ/146/85
LR = Luhman+, 2000, J/ApJ/540/1016
Sta = K. Stassun 2005, private communication,
low dispersion spectra,taken from
Hillenbrand+, 2013, J/AJ/146/85
Par = Parenago,1954, II/171
Dae = Daemgen+, 2012A&A...540A..46
CK = Cohen & Kuhi, 1979ApJS...41..743C 1979ApJS...41..743C
HB = Herbst+, 2002, J/A+A/396/513
GS = Greenstein & Struve, 1946PASP...58..366G 1946PASP...58..366G
SHC = optical spectral types from Slesnick+, 2004ApJ...610.1045S 2004ApJ...610.1045S
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 12-Feb-2024