J/MNRAS/337/133 UBV(RI)c photometry in clusters Tr 1 and Be 11 (Yadav+, 2002)
A deep UBVRI CCD photometric study of the open clusters Tr 1 and Be 11.
Yadav R.K.S., Sagar R.
<Mon. Not. R. Astron. Soc. 337, 133 (2002)>
=2002MNRAS.337..133Y 2002MNRAS.337..133Y
ADC_Keywords: Clusters, open ; Photometry, CCD ; Photometry, UBVRI
Keywords: Hertzsprung-Russell (HR) diagram -
stars: luminosity function, mass function -
open cluster and associations: individual: Tr 1 -
open cluster and associations: individual: Be 11 -
galaxies: stars clusters
Abstract:
We present deep UBV(RI)C charge-coupled device (CCD) photometry for
the young open star clusters Tr 1 and Be 11. The CCD data for Be 11
are obtained for the first time. The sample consists of ∼1500 stars
reaching down to V∼21mag. Analysis of the radial distribution of the
stellar surface density indicates that radius values for Tr 1 and
Be 11 are 2.3 and 1.5pc, respectively. The interstellar extinction
across the face of the imaged clusters region seems to be non-uniform
with a mean value of E(B-V)=0.60±0.05 and 0.95±0.05mag for Tr 1
and Be 11, respectively. A random positional variation of E(B-V) is
present in both the clusters. In the cluster Be 11, the reason for the
random positional variation may be the apparent association of the
H II region (S 213). The 2MASS JHK data in combination with the optical
data in the cluster Be 11 yield E(J-K)=0.40±0.20mag and
E(V-K)=2.20±0.20mag. Colour excess diagrams indicate a normal
interstellar extinction law in the direction of the cluster Be 11.
Description:
The UBV Johnson and RI Cousins observations were obtained, using a
2KxK CCD system at the f/13 Cassegrain focus of the Sampurnanand
104-cm telescope of the State Observatory, Nainital during 2000
November. Each pixel of a 2048x2048 CCD corresponds to a square
of size 0.36" on the sky.
Objects:
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RA (2000) DE Designation(s)
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01 35 40 +61 17 20 Trumpler 1 cluster = C 0132+610
01 35 40 +61 02 20 Trumpler 1 field
04 20 36 +44 55 58 Berkeley 11 cluster = C 0417+448
04 20 34 +44 40 08 Berkeley 11 field
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tr1.dat 57 1289 *Trumpler 1 cluster (in table4 or paper)
tr1f.dat 54 892 Trumpler 1 field region (in table4 or paper)
be11.dat 57 587 Berkeley 11 cluster (in table5 of paper)
be11f.dat 53 298 Bekeley 11 field region (in table5 of paper)
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Note on tr1.dat: electronic table4 of paper looks corrupted (March 2006),
see the "History" section below
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Byte-by-byte Description of file: *.dat
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Bytes Format Units Label Explanations
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1 A1 --- n_Seq [F] 'F' for field (F) star (files *f.dat)
2- 5 I4 --- Seq Sequential number of the star (1)
7- 12 F6.2 pix Xpos X position (2)
14- 19 F6.2 pix Ypos Y position (2)
21- 26 F6.3 mag Vmag Johnson V magnitude
28- 33 F6.3 mag U-B ? Johnson U-B colour index
35- 40 F6.3 mag B-V ? Johnson B-V colour index
42- 47 F6.3 mag V-Rc ? Johnson-Cousins V-Rc colour index
49- 54 F6.3 mag V-Ic ? Johnson-Cousins V-Ic colour index
56- 57 A2 --- Mem [m nm] Photometric membership
(table4a.dat and table5a.dat only)
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Note (1): Star designations in Simbad:
-- For Trumpler 1 : Cl* Trumpler 1 PJ NNNN
- In the cluster, No 1 to 539 are from Phelps & Janes
(1994ApJS...90...31P 1994ApJS...90...31P); stars not observed earlier have
a number starting with 1001.
- In the field region (table tr1f.dat), stars are numbered
in the increasing order of X value, numbers 1 to 892.
-- For Berkeley 11 : Cl* Berkeley 11 YS NNN
In the cluster and the field region, the stars are numbered
in increasing order of X value.
Note (2): East is up and north is left. 1pix=0.72arcsec
Finding charts are in Fig.1 of the paper.
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History:
* 07-Jan-2003: from electronic version of the journal
* 25-Mar-2006: electronic table for Tr 1 inconsistent;
tables tr1 and be11 copied from WEBDA archive data
(http://www.univie.ac.at/webda/archive_anon.html/)
and reformatted.
(End) James Marcout, Patricia Bauer [CDS] 25-Mar-2006