J/A+A/666/A55 Accretion variability monitoring in the ONC (Flaischlen+, 2022)
Monitoring accretion rate variability in the Orion Nebula Cluster with the
Wendelstein Wide Field Imager.
Flaischlen S., Preibisch T., Kluge M., Manara C.F., Ercolano B.
<Astron. Astrophys. 666, A55 (2022)>
=2022A&A...666A..55F 2022A&A...666A..55F (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, pre-main sequence ; YSOs ; X-ray sources ;
Accretion ; Photometry, SDSS
Keywords: protoplanetary disks - stars: pre-main sequence -
stars: statistics - X-rays: stars
Abstract:
The understanding of the accretion process has a central role in the
understanding of star and planet formation.
We aim to test how accretion variability influences previous
correlation analyses of the relation between X-ray activity and
accretion rates, which is important for understanding the evolution of
circumstellar disks and disk photoevaporation.
We monitored accreting stars in the Orion Nebula Cluster from November
24, 2014, until February 17, 2019, for 42 epochs with the Wendelstein
Wide Field Imager (WWFI) in the Sloan Digital Sky Survey u'g'r'
filters on the 2m Fraunhofer Telescope on Mount Wendelstein. Mass
accretion rates were determined from the measured ultraviolet excess.
The influence of the mass accretion rate variability on the relation
between X-ray luminosities and mass accretion rates was analyzed
statistically.
We find a typical interquartile range of ∼0.3dex for the mass
accretion rate variability on timescales from weeks to ∼2-years. The
variability has likely no significant influence on a correlation
analysis of the X-ray luminosity and the mass accretion rate observed
at different times when the sample size is large enough.
The observed anticorrelation between the X-ray luminosity and the mass
accretion rate predicted by models of photoevaporation-starved
accretion is likely not due to a bias introduced by different
observing times.
Description:
Reduced WWFI images of M42 for 42 epochs and the derived SDSS u'g'r'
photometry as well as deduced stellar parameters and mass accretion
rates.
Objects:
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RA (2000) DE Designation(s)
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05 35 17.3 -05 23 28 M42 = NAME Orion Nebula
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 89 57 YSOs analyzed in this study and effective
temperatures, extinctions, and distances
from the literature
table2.dat 74 744 SDSS u'g'r' photometry obtained with WWFI
table3.dat 115 432 Stellar parameters and accretion values of the
WWFI sample
list.dat 96 96 List of fits images
fits/* . 96 Individual fits images
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See also:
J/AJ/139/950 : JHKs photometry in ONC (Robberto+, 2010)
J/ApJ/748/14 : ONC population data from WFI observations (Da Rio+, 2012)
J/AJ/150/108 : Spectroscopy and HST imaging in ONC (O'Dell+, 2015)
J/A+A/648/A121 : X-ray activity and accretion in the ONC (Flaischlen+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Object name (1)
27- 28 I2 h RAh Right ascension (J2000)
30- 31 I2 min RAm Right ascension (J2000)
33- 37 F5.2 s RAs Right ascension (J2000)
39 A1 --- DE- Declination sign (J2000)
40- 41 I2 deg DEd Declination (J2000)
43- 44 I2 arcmin DEm Declination (J2000)
46- 49 F4.1 arcsec DEs Declination (J2000)
52- 55 I4 K Teff Effective temperature
58- 62 F5.2 mag AV Extinction in the V band (2)
65- 69 F5.1 pc Dist Distance (3)
72- 76 F5.1 pc e_Dist Lower uncertainty on Dist
79- 83 F5.1 pc E_Dist Upper uncertainty on Dist
86- 89 A4 --- Notes Notes on Teff and Dist (4)
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Note (1): Name of the YSO as listed in SIMBAD.
Note (2): Extinctions from Manara et al. (2012ApJ...755..154M 2012ApJ...755..154M,
Cat. J/ApJ/755/154).
Note (3): Distance calculated by inverting the parallax from Gaia EDR3, see
Gaia Collaboration et al. (2016A&A...595A...1G 2016A&A...595A...1G, Cat. I/337, Gaia DR1),
Gaia Collaboration et al. (2021A&A...649A...1G 2021A&A...649A...1G, Cat. I/350, Gaia EDR3),
Riello et al. (2021, A&A, in prep.),
Note (4): The field can have the values 4, 5, and/or 6, defined as follows:
4 = Effective temperatures calculated with the temperature scales of
Kenyon & Hartmann (1995ApJS..101..117K 1995ApJS..101..117K, Cat. J/ApJS/101/117)
(K type stars) and Luhman et al. (2003ApJ...593.1093L 2003ApJ...593.1093L,
Cat. J/ApJ/593/1093) (M type stars) with the spectral types
from Hillenbrand et al. (2013AJ....146...85H 2013AJ....146...85H, Cat. J/AJ/146/85).
5 = Effective temperatures taken from Da Rio et al. (2010ApJ...722.1092D 2010ApJ...722.1092D,
Cat. J/ApJ/722/1092).
6 = Distance set to the mean distance of the ONC (403 pc) determined
by Kuhn et al. (2019ApJ...870...32K 2019ApJ...870...32K).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name Object name as listed in SIMBAD
27- 35 F9.1 d JD Julian date of the observation
38- 42 F5.2 mag umag SDSS uprime magnitude
44- 48 F5.2 mag e_umag Uncertainty of umag
51- 55 F5.2 mag gmag SDSS gprime magnitude
57- 61 F5.2 mag e_gmag Uncertainty of gmag
64- 68 F5.2 mag rmag SDSS rprime magnitude
70- 74 F5.2 mag e_rmag Uncertainty of rmag
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Name Object name (1)
17- 25 F9.1 d JD Julian date (2)
27- 31 F5.2 mag Av Extinction in the V band
33- 37 F5.2 mag e_Av Uncertainty of Av
40- 44 F5.2 [Lsun] LAcc Log of the accretion luminosity
46- 50 F5.2 [Lsun] e_LAcc Uncertainty of LAcc
53- 57 F5.2 [Lsun] LBol Log of the bolometric luminosity
59- 63 F5.2 [Lsun] e_LBol Uncertainty of LBol
65- 69 F5.2 Rsun Rad Stellar radius
71- 75 F5.2 Rsun e_Rad Uncertainty of Rad
77- 81 F5.2 Msun Mass Stellar mass (3)
83- 87 F5.2 Msun e_Mass Uncertainty of Mass
89- 93 F5.2 [yr] LAge Log of the isochronal age (3)
95- 99 F5.2 [yr] e_LAge Uncertainty of LAge
102-106 F5.2 [Msun/yr] LMacc Log of the mass accretion rate
108-112 F5.2 [Msun/yr] e_LMacc Uncertainty of LMacc
115 I1 --- CL [0/4] Confidence level (4)
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Note (1): Name of the YSO as listed in SIMBAD.
Note (2): Epoch of the observation.
Note (3): Obtained with PARSEC 1.2S isochrones and mass tracks from
Bressan et al. (2012MNRAS.427..127B 2012MNRAS.427..127B).
Note (4): The uncertainties of Av, LAcc, and LBol were estimated with a Monte
Carlo method by varying the uncertainties of the input values assuming
Gaussian. A confidence level was defined depending on the number of successful
iterations as follows:
3 = 3 σ, all iterations were successful
2 = 2 σ, at least 95 percent of the iterations were successful
1 = 1 σ, at least 68 percent of the iterations were successful
0 = 0 σ, less than 68 percent of the iterations were successful
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 10 F10.2 d JD Julian Date of the observation
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 23 F5.2 s RAs Right ascension (J2000)
25 A1 --- DE- Declination sign (J2000)
26- 27 I2 deg DEd Declination (J2000)
29- 30 I2 arcmin DEm Declination (J2000)
32- 35 F4.1 arcsec DEs Declination (J2000)
37- 39 F3.1 arcsec/pix Scale Scale of the image
41- 45 I5 --- Nx Number of pixels along X-axis
47- 51 I5 --- Ny Number of pixels along Y-axis
53- 63 A11 --- Filter Filter
65- 68 I4 s Exp Total accumulated exposure time
70- 75 I6 Kibyte size Size of FITS file
77- 96 A20 --- File Name of the fits file in the subdirectory fits
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Acknowledgements:
Stefan Flaischlen, sflaisch(at)usm.lmu.de
(End) S. Flaischlen [Univ.-Sternwarte Muenchen], P. Vannier [CDS] 08-Aug-2022