J/MNRAS/452/525 M83 young star cluster light profiles (Ryon+, 2015)
Sizes and shapes of young star cluster light profiles in M83.
Ryon J.E., Bastian N., Adamo A., Konstantopoulos I.S., Gallagher J.S.III,
Larsen S., Hollyhead K., Silva-Villa E., Smith L.J.
<Mon. Not. R. Astron. Soc., 452, 525-539 (2015)>
=2015MNRAS.452..525R 2015MNRAS.452..525R (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Associations, stellar ; Morphology
Keywords: galaxies: individual: M83 - galaxies: star clusters: general
Abstract:
We measure the radii and two-dimensional light profiles of a large
sample of young, massive star clusters in M83 using archival HST/Wide
Field Camera 3 (WFC3) imaging of seven adjacent fields. We use galfit
to fit the two-dimensional light profiles of the clusters, from which
we find effective (half-light) radii, core radii, and slopes of the
power-law (EFF) profile (η). We find lognormal distributions of
effective radius and core radius, with medians of ∼2.5 and ∼1.3pc,
respectively. Our results provide strong evidence for a characteristic
size of young, massive clusters. The average effective radius and core
radius increase somewhat with cluster age. Little to no change in
effective radius is observed with increasing galactocentric distance,
except perhaps for clusters younger than 100Myr. We find a shallow
correlation between effective radius and mass for the full cluster
sample, but a stronger correlation is present for clusters 200-300Myr
in age. Finally, the majority of the clusters are best fit by an EFF
model with index η ≲3.0. There is no strong evidence for change
in η with cluster age, mass, or galactocentric distance. Our
results suggest that clusters emerge from early evolution with similar
radii and are not strongly affected by the tidal field of M83.
Mass-loss due to stellar evolution and/or giant molecular cloud
interactions appear to dominate cluster expansion in the age range we
study.
Description:
We use archival HST/Wide Field Camera 3 (WFC3) imaging data retrieved
from the Mikulski Archive for Space Telescopes, which were calibrated
and drizzled on-the-fly when requested for download. These data were
obtained by two programmes, 11360 (PI: O'Connell) and 12513 (PI:
Blair). In total, seven fields were observed across the disc of M83
between 2009 August and 2012 September.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 115 478 Properties of YMCs in M83
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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- 5 I5 --- ID Object identifier
7- 15 F9.5 deg RAdeg Right Ascension (J2000)
17- 25 F9.5 deg DEdeg Declination (J2000)
27- 32 F6.4 kpc Dgc Galatocentric distance
34- 38 F5.2 pix FWHM Full width at half maximum
40- 43 F4.2 pix e_FWHM Error in FWHM
45- 49 F5.2 --- Eta Power-law slope of EFF light profile
51- 55 F5.2 --- e_Eta Error in Eta
57- 61 F5.2 [pc] logReff Log of half-light radius
63- 68 F6.2 [pc] e_logReff Error in log Reff
70- 74 F5.2 [pc] logRcore Log of core radius
76- 80 F5.2 [pc] e_logRcore Error in log Rcore
82- 86 F5.2 [yr] logAge Log of age
88- 92 F5.2 [yr] b_logAge Minimum logAge
94- 98 F5.2 [yr] B_logAge Maximum logAge
100-103 F4.2 [Msun] logMass Log of mass
105-108 F4.2 [Msun] b_logMass Minimum logMass
110-113 F4.2 [Msun] B_logMass Maximum logMass
115 I1 --- fiso [1/2] Isolation flag (1)
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Note (1): Isolation flag as follows:
1 = Isolated: no nearby sources, or sources are faint enough to be
indistinguishable from sky background.
2 = Somewhat isolated: one or a few faint sources, or slight fluctuations
in sky background.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 14-Jan-2016