J/AJ/161/138 Photometry of 38708 stars in W3 complex with HST (Huston+, 2021)
The initial mass function of low-mass stars and brown dwarfs in the W3 complex.
Huston M.J., Luhman K.L.
<Astron. J., 161, 138 (2021)>
=2021AJ....161..138H 2021AJ....161..138H
ADC_Keywords: Star Forming Region; Stars, brown dwarf; Photometry, HST
Keywords: Brown dwarfs ; Initial mass function ; Star-forming regions ;
Hubble Space Telescope
Abstract:
We have used archival infrared images obtained with the Wide Field
Camera 3 on board the Hubble Space Telescope to constrain the initial
mass function of low-mass stars and brown dwarfs in the W3
star-forming region. The images cover 438arcmin2, which encompasses
the entire complex, and were taken in the filters F110W, F139M, and
F160W. We have estimated extinctions for individual sources in these
data from their colors and have dereddened their photometry
accordingly. By comparing an area of the images that contains the
richest concentration of previously identified W3 members to an area
that has few members and is dominated by background stars, we have
estimated the luminosity function for members of W3 with masses of
0.03-0.4M☉. That luminosity function closely resembles data in
typical nearby star-forming regions that have much smaller stellar
populations than W3 ( ∼500 versus several thousand objects). Thus, we
do not find evidence of significant variations in the initial mass
function of low-mass stars and brown dwarfs with star-forming
conditions, which is consistent with recent studies of other distant
massive star-forming regions.
Description:
Images of W3 were taken with the infrared channel of Wild Field Camera
3 (WFC3) through program 15238 (PI: A.Kraus). The camera's array has a
format of 1014x1014pixels where each pixel has a size of
∼0.135x0.121", corresponding to a field of view of 136x123". The WFC3
images were taken with three filters, F110W (0.9-1.2µm), F139M
(1.35-1.41µm), and F160W (1.4-1.7µm).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 52 38708 Sources in WFC3 images of W3
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
VI/125 : Theoretical spectra of red giants and supergiants (Lancon+, 2007)
J/ApJS/209/32 : Probable young stars in the MYStIX project (Broos+, 2013)
J/A+A/561/A12 : W3 Main JHKs photometry (Bik+, 2014)
J/ApJ/813/42 : O and B type stars in W3: first results (Kiminki+, 2015)
J/AJ/153/46 : Spectroscopy of candidate members in Taurus (Luhman+, 2017)
J/AJ/158/54 : New Taurus memb. from stellar to planetary masse (Esplin+,2019)
J/ApJ/881/79 : Flamingos-2 near-infrared photometry in NGC 2244 (Muzic+, 2019)
J/MNRAS/487/2771 : Gaia-DR2 distance to the W3 Complex (Navarete+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 F9.6 deg RAdeg [36.1/37.1] Right Ascension (J2000)
11- 19 F9.6 deg DEdeg [61.8/62.4] Declination (J2000)
21- 25 F5.2 mag 110mag [16.75/25.52]? F110W magnitude from HST WFC3
27- 30 F4.2 mag e_110mag [0.02/0.2]? Error in 110mag
32- 36 F5.2 mag 139mag [15.06/23.57]? F139M magnitude from HST WFC3
38- 41 F4.2 mag e_139mag [0.02/0.2]? Error in 139mag
43- 47 F5.2 mag 160mag [15.35/23.45]? F160W magnitude from HST WFC3
49- 52 F4.2 mag e_160mag [0.02/0.2]? Error in 160mag
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 29-Apr-2021