J/A+A/443/157 CCD photometry in 6 open clusters (Paunzen+, 2005)
CCD photometric search for peculiar stars in open clusters.
VI. NGC 1502, NGC 3105, Stock 16, NGC 6268, NGC 7235 and NGC 7510.
Paunzen E., Netopil M., Iliev I.K., Maitzen H.M., Claret A., Pintado O.I.
<Astron. Astrophys., 443, 157-162 (2005)>
=2005A&A...443..157P 2005A&A...443..157P
ADC_Keywords: Clusters, globular ; Photometry, CCD ; Stars, peculiar
Keywords: stars: chemically peculiar - stars: early-type -
techniques: photometric - Galaxy: globular clusters: general
Abstract:
Within the sample of six young open clusters (NGC 1502, NGC 3105,
Stock 16, NGC 6268, NGC 7235 and NGC 7510) we have investigated 1753
objects using the narrow band, three filter Delta a photometric system
resulting in the detection of eleven bona-fide magnetic chemically
peculiar (CP) stars and five Be or metal-weak stars. The results for
the distant cluster NGC 3105 is most important because of the still
unknown influence of the global metallicity gradient of the Milky Way.
These findings confirms that CP stars are present in open clusters of
very young ages (logt≥6.90) at galactocentric distances up to
11.4kpc. For all programme clusters the age, reddening and distance
modulus were derived using the corresponding isochrones. Some
additional variable stars within Stock 16 could be identified by
comparing different photometric studies.
Description:
The Observations of the six open clusters were performed at four
different sites and telescopes:
1.82m telescope (Cima Ekar, Asiago), AFOSC, 1024x1024 pixel CCD
2m RCC telescope (BNAO, Rozhen), direct imaging, 1024x1024 pixel CCD
0.9m telescope (CTIO), direct imaging, SITe 2084x2046 pixel CCD
3.6m telescope (ESO-La Silla), EFOSC2, 2048x2048 pixel CCD
The observations were performed with two different filter sets, both
having the following characteristics:
g1(5007±126Å) g2(5199±95Å) y(5466±108Å).
and a is defined by
a = g2 - (g1+y)/2
Objects:
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RA (2000) DE Designation(s) (File)
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04 07 54. +62 20 00 NGC 1502 = C 0403+622 (table4.dat)
10 00 48. -54 46 00 NGC 3105 = C 0959-545 (table5.dat)
13 18 48. -62 31 00 Stock 16 = C 1315-623 (table6.dat)
17 02 40.4 -39 44 18 NGC 6268 = C 1658-396 (table7.dat)
22 12 24. +57 16 00 NGC 7235 = C 2210+570 (table8.dat)
23 11 00. +60 34 00 NGC 7510 = C 2309+603 (table9.dat)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 64 40 Observed program stars of NGC 1502
table5.dat 64 1305 Observed program stars of NGC 3105
table6.dat 64 93 Observed program stars of Stock 16
table7.dat 64 62 Observed program stars of NGC 6268
table8.dat 64 129 Observed program stars of NGC 7235
table9.dat 64 124 Observed program stars of NGC 7510
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See also:
GCPD/75 : the Maitzen photometric system (1976A&A....51..223M 1976A&A....51..223M)
J/A+A/371/L5 : CCD Δa-photometry of NGC 1866 (Maitzen+, 2001)
J/A+A/373/153 : CCD Δa-photometry of 5 open clusters (Paunzen+, 2001)
J/A+A/385/867 : CCD Δa-photometry of 5 open clusters (Paunzen+, 2002)
J/A+A/395/823 : CCD Δa-photometry of 5 open clusters (Paunzen+, 2002)
J/A+A/412/721 : CCD Δa-photometry of 5 open clusters (Paunzen+, 2003)
Byte-by-byte Description of file: table?.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- No1 ? Notation for stars sorted after X and Y (1)
6- 9 I4 --- No2 ? Notation according to WEBDA (2)
11- 16 F6.1 pix Xpos X coordinate
18- 24 F7.1 pix Ypos Y coordinate
26- 31 F6.3 mag Vmag Mean V magnitude
33- 38 F6.3 mag amag Mean a index
40- 44 F5.3 mag e_amag rms uncertainty on amag
46- 51 F6.3 mag g1-y Mean (g1-y) colour index
53- 57 F5.3 mag e_g1-y rms uncertainty on (g1-y)
59- 64 F6.3 mag da(g1-y) ? Deviation from cluster line (Delta a)
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Note (1): Sequential number in tables 5 (NGC 3105), 7 (NGC 6268), 8 (NGC 7235)
Note (2): Only WEBDA number in tables 4 (NGC 1502), 6 (Stock 16), 9 (NGC 7510)
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Acknowledgements: Ernst Paunzen, Ernst.Paunzen(at)univie.ac.at
(End) Patricia Vannier [CDS] 08-Nov-2005