J/MNRAS/472/1760 Hierarchical formation of Westerlund 1 (Gennaro+, 2017)
Hierarchical formation of Westerlund 1:
a collapsing cluster with no primordial mass segregation?
Gennaro M., Goodwin S.P., Parker R.J., Allison R.J., Brandner W.
<Mon. Not. R. Astron. Soc., 472, 1760-1769 (2017)>
=2017MNRAS.472.1760G 2017MNRAS.472.1760G (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Photometry, infrared ; Photometry, UBVRI
Keywords: stars: kinematics and dynamics -
open clusters and associations: individual: Westerlund 1
Abstract:
We examine the level of substructure and mass segregation in the
massive, young cluster Westerlund 1. We find that it is relatively
smooth, with little or no mass segregation, but with the massive stars
in regions of significantly higher than average surface density. While
an expanding or bouncing-back scenario for the evolution of
Westerlund 1 cannot be ruled out, we argue that the most natural model
to explain these observations is one in which Westerlund 1 formed with
no primordial mass segregation and at a similar or larger size than we
now observe.
Description:
Photometry of stars in the Westerlund 1 cluster field of view and
inferred masses. The catalog contains new photometric measurements
using data from the SofI instrument on the NTT/ESO telescope. In
addition to our original measurements, our catalog has been completed
using data from the 2MASS Point Source Catalog (Skrutskie et al. 2006,
Cat. VII/233), and from Bonanos (2007, Cat. J/AJ/133/2696) and
Negueruela et al. (2010A&A...516A..78N 2010A&A...516A..78N).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 230 6080 Selected rows and columns from the full
photometric catalogue
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AJ/133/2696 : BVRI light curves of Westerlund 1 stars (Bonanos, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID Identification Number
6- 16 F11.7 deg RAdeg Right Ascension (J2000)
18- 28 F11.7 deg DEdeg Declination (J2000)
30- 38 A9 --- Source Catalog from which the photometric mass has
been inferred
40 I1 --- Cl [0/1] Flag indicating whether or not the star
has been removed from the catalog using
sigma-clipping (0:removed, 1:kept) (1)
42 I1 --- Sb [0/1] Flag indicating whether or not the star
has been removed from the catalog using
statistical field subtraction
(0:removed, 1:kept) (1)
44- 48 F5.3 --- Prob Membership probability
50- 54 F5.2 Msun MNIR ?=0 Mass obtained from Near Infrared photometry
56- 60 F5.2 Msun MOPT ?=0 Mass obtained from Optical photometry
62- 66 F5.2 mag JSmag ?=0 J band photometry from SofI observations,
calibrated on the 2MASS system
68- 71 F4.2 mag e_JSmag ?=0 SofI J band photometric error
73- 77 F5.2 mag HSmag ?=0 H band photometry from SofI observations,
calibrated on the 2MASS system
79- 82 F4.2 mag e_HSmag ?=0 SofI H band photometric error
84- 88 F5.2 mag KsSmag ?=0 Ks band photometry from SofI observations,
calibrated on the 2MASS system
90- 93 F4.2 mag e_KsSmag ?=0 SofI Ks band photometric error
95- 99 F5.2 mag J2mag ?=0 J band photometry from the 2MASS-PSC
(Skrutskie et al., 2006, Cat. VII/233)
101-104 F4.2 mag e_J2mag ?=0 2MASS-PSC J band photometric error
106-110 F5.2 mag H2mag ?=0 H band photometry from the 2MASS-PSC
(Skrutskie et al., 2006, Cat. VII/233)
112-115 F4.2 mag e_H2mag ?=0 2MASS-PSC H band photometric error
117-121 F5.2 mag Ks2mag ?=0 Ks band photometry from the 2MASS-PSC
(Skrutskie et al., 2006, Cat. VII/233)
123-126 F4.2 mag e_Ks2mag ?=0 2MASS-PSC Ks band photometric error
128-137 A10 --- IDN Object ID, Cl* Westerlund 1 WNNa in Simbad
(Negueruela et al., 2010A&A...516A..78N 2010A&A...516A..78N)
139-148 A10 --- SpTypeN Spectral Type
(Negueruela et al., 2010A&A...516A..78N 2010A&A...516A..78N)
150-154 F5.2 mag BNmag ?=0 B band photometry
(Negueruela et al., 2010A&A...516A..78N 2010A&A...516A..78N)
156-160 F5.2 mag VNmag ?=0 V band photometry
(Negueruela et al., 2010A&A...516A..78N 2010A&A...516A..78N)
162-166 F5.2 mag RNmag ?=0 R band photometry
(Negueruela et al., 2010A&A...516A..78N 2010A&A...516A..78N)
168-172 F5.2 mag INmag ?=0 I band photometry
(Negueruela et al., 2010A&A...516A..78N 2010A&A...516A..78N)
174-188 A15 --- IDB Object ID (Bonanos, 2007, Cat. J/AJ/133/2696)
190-206 A17 --- SpTypeB Spectral Type
(Bonanos, 2007, Cat. J/AJ/133/2696)
208-212 F5.2 mag BBmag ?=0 B band photometry
(Bonanos, 2007, Cat. J/AJ/133/2696)
214-218 F5.2 mag VBmag ?=0 V band photometry
(Bonanos, 2007, Cat. J/AJ/133/2696)
220-224 F5.2 mag RBmag ?=0 R band photometry
(Bonanos, 2007, Cat. J/AJ/133/2696)
226-230 F5.2 mag IBmag ?=0 I band photometry
(Bonanos, 2007, Cat. J/AJ/133/2696)
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Note (1): Flag as follows:
0 = removed
1 = kept
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 22-Jun-2020