J/A+A/616/A40 BV photometry of Bochum 7 members (Corti+, 2018)
A search of OB stars in the field of the galactic OB association Bochum 7.
II. Proper motion and IR photometry.
Corti M.A., Orellana R.B., Bosch G.L.
<Astron. Astrophys. 616, A40 (2018)>
=2018A&A...616A..40C 2018A&A...616A..40C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Photometry, UBV ; Stars, OB
Keywords: stars: early-type - proper motions - catalogs -
open clusters and associations: individual: Bochum 7
Abstract:
We plan to identify the members of the Bochum 7 association by
performing simultaneous astrometric and spectrophotometric analyses,
and estimate its distance and evolutionary stage.
We used our own visual spectroscopic and UBV photometric data of a
30°x30° region centered at RA=8:44:47.2, DE=-45:58:55.5. This
information enabled us to estimate the spectral classification and
distance of all stars present in the region. The proper motion was
analyzed with data of the UCAC 5 catalog and was used to identify the
members of this association. We added JHK data from 2MASS and IRAS
catalogs to check for the presence of infrared (IR) excess stars.
We found that Bochum 7 is an OB association with at least 27
identified stellar members (l=265.12°, b=-2°) at a distance of
~=5640pc. Its proper motion is pmRAcosDE=-4.92±0.08mas/yr,
pmDE=3.26±0.08mas/yr. We derived an average heliocentric radial
velocity of ∼35km/s and were able to confirm the binary nature of the
(ALS 1135) system and detect four new binary star candidates. Analysis
of data for massive Bo 7 star candidates points towards a young age
(≤3x106 years old) for the association, although the presence of a
previous episode of star formation remains to be analyzed.
Description:
We selected stars with V<15mag and reddening-free parameter Q←0.3
(Schmidt-Kaler. Th. 1982, In Landolt-Bornstein New Series, Group VI,
Vol. 2b.) in the 30' x30' photometric image centered at
~=α=08:45, δ=-45:59 (l= 265.12°, b=-2.0°) and found
248 probable members of Bochun 7 association.
Table 3 shows the photometric ID in column 1, celestial coordinates
J2000.0 in columns 2 and 3, magnitudes V and B and color (B-V) in
columns 4, 5 and 6, respectively. The last column lists the
reddening-free parameter Q of each 248 probable members of Bochum 7
association.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 49 248 Candidates proposed as members of Bochum 7
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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- 4 I4 --- ID Identification number
6- 12 F7.5 h RAhour Right ascension in decimal hours (J2000.0)
14- 22 F9.5 deg DEdeg Declination (J2000.0)
24- 28 F5.2 mag Vmag V magnitude
30- 35 F6.3 mag Bmag B magnitude
37- 42 F6.3 mag B-V B-V colour index
44- 49 F6.3 mag Q Reddening-free parameter Q
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Acknowledgements:
Mariela A. Corti, mariela.a.corti(at)gmail.com
References:
Corti et al. et al., Paper I 2007A&A...467..137C 2007A&A...467..137C
History:
13-Aug-2018: on-line version
26-Nov-2019: units of RA corrected into hours
(End) Patricia Vannier [CDS] 30-Apr-2018