CDROM/AJ/V105/P1441
IC 4665 (Prosser 1993)
=========================================================================
=======
The Open Cluster IC 4665
Charles F. Prosser
<1993, AJ, 105, 1441>
=1993AJ....105.1441P
=========================================================================
=======
Abstract:
The results of a combined astrometric, photometric, and spectroscopic
program to identify members of the open cluster IC 4665 are presented.
Numerous new proper motion/photometric candidate members and at least
23 M dwarfs with H-alpha emission have been identified. A reanalysis
of IC 4665's age using different methods yields conflicting results
ranging from approx. 3x10^7 yr to the age of the Pleiades. This study
provides a list of candidate cluster members in the intermediate and
low-mass regime of this cluster. Future spectroscopic observations of
these candidates should eventually identify true cluster members. The
results of new echelle observations of some candidates and the
photometric monitoring of one apparent cluster member are given in an
appendix.
File Summary:
------------------------------------------------------------------------------File Name
Lrecl
Records
Explanations
------------------------------------------------------------------------------table1.dat
120
55
IC 4665: 30 s proper motion candidates
table2.dat
120
142
IC 4665: Yerkes and Lick proper motion
candidates
------------------------------------------------------------------------------Byte-by-byte Description of file: table1.dat
------------------------------------------------------------------------------Bytes Format Units
Label
Explanations
------------------------------------------------------------------------------1- 3
I3
--P
Running identification number, P
4- 5
2X
----Blank
6-10
F5.2
mag
V
Johnson V magnitude
11-15
F5.2
mag
B-V
[]? B-V color
16-20
F5.2
mag
V-I
[]? V-I color
21-25
F5.2
mag
R-I
[]? R-I color
26
1X
----Blank
27-28
I2
--n_V
Number of observations at V
magnitude
29-30
I2
--n_B
Number of observations at B
magnitude
31-32
I2
--n_I
Number of observations at I
magnitude
33-34
I2
--n_R
Number of observations at R
magnitude
35
1X
----Blank
36-38
F3.0
h
RAh
Right ascension 1950
39-41
F3.0
min
RAm
R.A.
42-47
F6.2
s
RAs
R.A.
48
A1
--DESign of declination, always blank
49-50
F2.0
deg
DEd
Declination 1950
51-53
F3.0
arcmin
DEm
Dec.
54-58
F5.1
arcsec
DEs
Dec.
59
1X
----Blank
60-66
F7.2
mm
X
Survey coordinates, X
67-73
F7.2
mm
Y
Survey coordinates, Y
74-80
F7.2
0.01arcsec/yr mu_x
Relative proper motion component,
mu_x
81-87
F7.2
0.01arcsec/yr mu_y
Relative proper motion component,
mu_y
88-93
F6.2
0.01arcsec/yr e_mu_x Error in mu_x, sigma_x
94-99
F6.2
0.01arcsec/yr e_my_y Error in mu_y, sigma_y
100-101 2X
----Blank
102-105 A4
--Prob
*Proper motion membership
probability
106-108 6X
----Blank
112-113 A2
--Phot
Membership on the basis of
photometry
114-115 2X
----Blank
116-120 A5
--Other
Other previous identifications
------------------------------------------------------------------------------Notes for file: table1.dat
------------------------------------------------------------------------------Prob:
A proper motion membership probability has been determined from
gaussian fitting to the cluster and field proper motion
distributions - however the reader is advised not to attach great
weight to the probabilities calculated due to the high contamination
of field stars found for this cluster.
------------------------------------------------------------------------------Comments for file: table2.dat
------------------------------------------------------------------------------Table 2 lists the proper motion candidates recovered from analysis of
the Lick 36-inch and Yerkes 40-inch plates. The format of Table 2 is
the same as for Table 1, with the addition of a column which gives the
number, 'N', of Yerkes plate fields (see printed paper) which
contributed a proper motion estimate for the star. Relative proper
motions from analysis of more than one Yerkes field were averaged
together. No proper motion membership probabilities were calculated
for the Lick candidates in Table 2 due to the rough approximations
made to correct for magnitude dependent effects in the proper motions
during the analysis of the Lick 30min/1hr plate reductions.
The first 27 entries in Table 2 are those stars for which proper
motions had also been derived from the Lick short exposure plates
(Table 1). These 27 entries are separated by a blank line from those
remaining Yerkes/Lick proper motion candidates which were not measured
on the short exposure plates.
------------------------------------------------------------------------------Byte-by-byte Description of file: table2.dat
------------------------------------------------------------------------------Bytes Format Units
Label
Explanations
------------------------------------------------------------------------------1- 3
I3
--P
Running identification number, P
4- 5
2X
----Blank
6-10
F5.2
mag
V
Johnson V magnitude
11-15
F5.2
mag
B-V
[]? B-V color
16-20
F5.2
mag
V-I
[]? V-I color
21-25
F5.2
mag
R-I
[]? R-I color
26
1X
----Blank
27-28
I2
--n_V
Number of observations at V
magnitude
29-30
I2
--n_B
Number of observations at B
magnitude
31-32
I2
--n_I
Number of observations at I
magnitude
33-34
I2
--n_R
Number of observations at R
magnitude
35
1X
----Blank
36-38
F3.0
h
RAh
Right ascension 1950
39-41
F3.0
min
RAm
R.A.
42-47
F6.2
s
RAs
R.A.
48
A1
--DESign of declination, always blank
49-50
F2.0
deg
DEd
Declination 1950
51-53
F3.0
arcmin
DEm
Dec.
54-58
F5.1
arcsec
DEs
Dec.
59
1X
----Blank
60-66
F7.2
mm
X
Survey coordinates, X
67-73
F7.2
mm
Y
Survey coordinates, Y
74-80
F7.2
0.01arcsec/yr mu_x
Relative proper motion component,
mu_x
81-87
F7.2
0.01arcsec/yr mu_y
Relative proper motion component,
mu_y
88-93
F6.2
0.01arcsec/yr e_mu_x Error in mu_x, sigma_x
94-99
F6.2
0.01arcsec/yr e_my_y Error in mu_y, sigma_y
100-101 2X
----Blank
102-105 A4
--Prob
*Proper motion membership
probability
106-108 3X
----Blank
109
I1
--N
Num. of Yerkes fields to determine
mu
110-111 2X
----Blank
112-113 A2
--Phot
Membership on the basis of
photometry
114-115 2X
----Blank
116-120 A5
--Other
Other previous identifications
------------------------------------------------------------------------------Notes for file: table2.dat
------------------------------------------------------------------------------Prob:
A proper motion membership probability has been determined from
gaussian fitting to the cluster and field proper motion
distributions - however the reader is advised not to attach great
weight to the probabilities calculated due to the high contamination
of field stars found for this cluster.
------------------------------------------------------------------------------=========================================================================
=======
(End)
Lee Brotzman [ADS] 28Feb-1995