J/MNRAS/453/106 NGC5617 and Trumpler 22 stars BV mag and RV (De Silva+, 2015)
Binary open clusters in the Milky Way:
photometric and spectroscopic analysis of NGC 5617 and Trumpler 22.
De Silva G.M., Carraro G., D'Orazi V., Efremova V., Macpherson H.,
Martell S., Rizzo L.
<Mon. Not. R. Astron. Soc., 453, 106-112 (2015)>
=2015MNRAS.453..106D 2015MNRAS.453..106D (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Photometry, UBV ; Radial velocities
Keywords: open clusters and associations: general -
open clusters and associations: individual: NGC 5617 -
open clusters and associations: individual: Trumpler 22
Abstract:
Using photometry and high-resolution spectroscopy we investigate for
the first time the physical connection between the open clusters NGC
5617 and Trumpler 22. Based on new CCD photometry we report their
spatial proximity and common age of ∼70Myr. Based on high-resolution
spectra collected using the HERMES and UCLES spectrographs on the
Anglo-Australian telescope, we present radial velocities and
abundances for Fe, Na, Mg, Al, Si, Ca, and Ni. The measured radial
velocities are -38.63±2.25km/s for NGC 5617 and -38.46±2.08km/s
for Trumpler 22. The mean metallicity of NGC 5617 was found to be
[Fe/H]=-0.18±0.02 and for Trumpler 22 was found to be
[Fe/H]=-0.17±0.04. The two clusters share similar abundances across
the other elements, indicative of a common chemical enrichment history
of these clusters. Together with common motions and ages we confirm
that NGC 5617 and Trumpler 22 are a primordial binary cluster pair in
the Milky Way.
Description:
The photometry used in this paper comes from two sources. In the case
of NGC 5617, modern CCD photometry in the UBVI passbands is available
from Carraro (2011, Cat. J/A+A/536/A101).
For Trumpler 22, only old photographic data exist (Haug,
1978A&AS...34..417H 1978A&AS...34..417H), and for this reason we exploit here a new data
set. Photometry in UBVI was acquired at Las Campanas Observatory on
the nights from 2011 June 03 and are published here for the first
time. We stress that this setup (telescope/instrument) is the same
that Carraro (2011, Cat. J/A+A/536/A101) used for NGC 5617.
Spectra were collected on the 3.9 m Anglo-Australian Telescope (AAT)
using the UCLES spectrograph (2012 March 5-6) and using the HERMES
multi-object spectrograph (2014 August 22) under service observation
time.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 67 56 Spectroscopic observations
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See also:
J/A+A/536/A101 : UBVI photometry towards (l=314,b=0) (Carraro, 2011)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Inst Instrument (UCLES or HERMES)
8- 18 A11 --- Cluster Cluster name
21- 24 I4 --- Star Star identification number within the cluster (1)
26- 27 I2 h RAh Right ascension (J2000)
29- 30 I2 min RAm Right ascension (J2000)
32- 36 F5.2 s RAs Right ascension (J2000)
38 A1 --- DE- Declination sign (J2000)
39- 40 I2 deg DEd Declination (J2000)
42- 43 I2 arcmin DEm Declination (J2000)
45- 49 F5.2 arcsec DEs Declination (J2000)
51- 55 F5.2 mag Vmag Johnson V magnitude
57- 60 F4.2 mag B-V Johnson B-V colour index
62- 67 F6.2 km.s RV Radial velocity
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Note (1): For HERMES observations of NGC 5617, star numbers from Carraro
(2011, Cat. J/A+A/536/A101).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 01-Aug-2016