J/A+A/531/A73 NGC 6167 and NGC 6193 multi-photometry (Baume+, 2011)
The Ara OB1a association. Stellar population and star formation history.
Baume G., Carraro G., Comeron F., de Elia G.C.
<Astron. Astrophys. 531, A73 (2011)>
=2011A&A...531A..73B 2011A&A...531A..73B
ADC_Keywords: Clusters, open ; Photometry, UBVRI ; Photometry, infrared
Keywords: Open clusters and associations: general -
open clusters and associations: individual: NGC 6193, NGC 6167 -
stars: formation - stars: pre-main sequence
Abstract:
The Ara OB1a association is a nearby complex in the fourth Galactic
quadrant where a number of young/embedded star clusters are projected
close to more evolved, intermediate age clusters. It is also rich in
interstellar matter, and contains evidences of the interplay between
massive stars and their surrounding medium, like the rim HII region
NGC 6188.
We provide more solid estimates of the fundamental parameters (age and
distance) of the two most prominent stellar clusters, NGC 6167 and NGC
6193, that may be used as a basis to study the star formation history
of the region.
The study is based on a photometric optical survey (UBVIHa) of NGC
6167 and NGC 6193 and their nearby field, complemented with public
data from 2MASS-VVV, UCAC3 and IRAC-Spitzer in this region.
We produced a uniform photometric catalogue and we estimated more
robustly the fundamental parameters for NGC 6167, NGC 6193 and the
IRAS 16375-4854 source. As a consequence, all of them are located at
approximately the same distance from the Sun in the Sagittarius-Carina
Galactic arm. However, the ages we estimated differ widely: NGC 6167
results to be an intermediate-age cluster (20-30Myr), NGC 6193 a very
young one (1-5Myr) with PMS, Hα emitters, and class II objects;
and the IRAS 16375-4854 source is revealed as the youngest of the
three containing several YSOs.
These results support a picture in which Ara OB1a is a region where
star formation has proceeded for several tens of Myr up to the
present. The difference in ages of different stellar groups can be
interpreted as a consequence of a triggered star formation process.
Additionally, in the specific case of NGC 6193, an indication of
possible non-coeval star formation was found.
Description:
Two astrometric, photometric (13 bands) catalogues covering both NGC
6167 (33193 objects) and NGC 6193 (39338 objects) regions. They
includes X-Y positions; 2MASS identification (when available);
equatorial coordinates (epoch J2000.0); optical (UBVI and Ha-on/off),
NIR 2MASS/VVV (JHK), MIR IRAC-SST (3.6, 4.5, 5,8 and 8.0 bands)
photometry.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ngc6167.dat 271 33193 Astrometry/photometry of NGC 6167 region
ngc6167.vot 217 265593 VOTable version of ngc6167.dat
ngc6193.dat 271 39338 Astrometry/photometry of NGC 6193 region
ngc6193.vot 217 314753 VOTable version of ngc6193.dat
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See also:
I/315 : UCAC3 Catalogue (Zacharias+ 2009)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: ngc6167.dat ngc6193.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq Sequential number
7- 18 F12.8 deg RAdeg Right ascension in decimal degrees (J2000)
20- 31 F12.8 deg DEdeg Declination in decimal degrees (J2000)
33- 39 F7.2 pix Xpos X position
41- 47 F7.2 pix Ypos Y position
49- 54 F6.3 mag Vmag Johnson V magnitude
56- 61 F6.3 mag e_Vmag ?=99.990 rms uncertainty on Vmag
63- 68 F6.3 mag B-V ?=99.990 B-V colour index
70- 75 F6.3 mag e_B-V ?=99.990 rms uncertainty on B-V
77- 82 F6.3 mag U-B ?=99.990 U-B colour index
84- 89 F6.3 mag e_U-B ?=99.990 rms uncertainty on U-B
91- 96 F6.3 mag V-I ?=99.990 V-I colour index
98-103 F6.3 mag e_V-I ?=99.990 rms uncertainty on V-I
105-110 F6.3 mag Ha ?=99.999 Hα index ΔHα
[=Hα(on)-Hα(off)]
112-117 F6.3 mag e_Ha ?=99.990 rms uncertainty on Ha
119-126 F8.3 0.1nm W(Ha) ?=999.990 Estimated Hα equivalent width
128-133 F6.3 0.1nm e_W(Ha) ?=99.990 rms uncertainty on W(Ha)
135-140 F6.3 mag Jmag ?=99.999 2MASS J magnitude
142-147 F6.3 mag e_Jmag ?=99.999 rms uncertainty on Jmag
149-154 F6.3 mag Hmag ?=99.999 2MASS H magnitude
156-161 F6.3 mag e_Hmag ?=99.999 rms uncertainty on Hmag
163-168 F6.3 mag Kmag ?=99.999 2MASS Ks magnitude
170-175 F6.3 mag e_Kmag ?=99.999 rms uncertainty on Kmag
177-182 F6.3 mag [3.6] ?=99.999 Spitzer/IRAC 3.6um magnitude
184-189 F6.3 mag e_[3.6] ?=99.999 rms uncertainty on [3.6]
191-196 F6.3 mag [4.5] ?=99.999 Spitzer/IRAC 4.5um magnitude
198-203 F6.3 mag e_[4.5] ?=99.999 rms uncertainty on [4.5]
205-210 F6.3 mag [5.8] ?=99.999 Spitzer/IRAC 5.8um magnitude
212-217 F6.3 mag e_[5.8] ?=99.999 rms uncertainty on [5.8]
219-224 F6.3 mag [8.0] ?=99.999 Spitzer/IRAC 8.0um magnitude
226-231 F6.3 mag e_[8.0] ?=99.999 rms uncertainty on [8.0]
233-238 F6.3 mag f.mag ?=99.999 UCAC3 fit magnitude (Cat. I/315)
240-247 F8.3 mas/yr pmRA ?=99.999 Proper motion along RA
249-255 F7.3 mas/yr e_pmRA ?=99.999 rms uncertainty on pmRA
257-264 F8.3 mas/yr pmDE ?=99.999 Proper motion along DE
266-271 F6.3 mas/yr e_pmDE ?=99.999 rms uncertainty on pmDE
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Acknowledgements:
Gustavo Baume, gbaume(at)fcaglp.fcaglp.unlp.edu.ar
(End) Patricia Vannier [CDS] 04-May-2011