J/AJ/119/1748 WFPC 2 imaging of young LMC clusters (Keller+, 2000)
Wide field planetary camera 2 imaging of young clusters in the
Magellanic clouds.
Keller S.C., Bessell M.S., Da Costa G.S.
<Astron. J. 119, 1748 (2000)>
=2000AJ....119.1748K 2000AJ....119.1748K
ADC_Keywords: Clusters, globular ; Colors ; HR diagrams ; Magellanic Clouds ;
Photometry, ultraviolet
Mission_Name: HST
Keywords: galaxies: star clusters - Magellanic Clouds - stars:
emission-line, Be - stars: evolution - ultraviolet emission
Abstract:
We have carried out Wide Field Planetary Camera 2 (WFPC2) F160BW,
F555W, and F656N imaging of four young populous clusters: NGC 330, in
the Small Magellanic Cloud, and NGC 1818, 2004, and 2100, in the Large
Magellanic Cloud. We report photometric results for these four
clusters, including identification using photometric colors of the
cluster Be star population. We present theoretical WFPC2 and broadband
colors and bolometric corrections for LMC and SMC metallicities. The
use of the far-UV F160BW filter enables accurate determination of the
effective temperatures for stars in the vicinity of the main-sequence
turnoff and on the unevolved main sequence.
Description:
The data presented in this paper were obtained by HST using WFPC2 in
1997 June. Exposures in F555W, F160BW, and F656N were obtained. The
F160BW filter (δλ = 446 Å, λeff = 1491 Å)
is a wideband filter with negligible red leak. The imaging and
transmission properties of the F160BW filter have been described by
Watson et al. (1994ApJ...435L..55W 1994ApJ...435L..55W). F656N is a narrowband filter
(δλ = 22 Å) centered on the H line.
Objects:
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RA (2000) DE Designation(s)
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00 56.2 -72 29 NGC 330 = ESO 29- 24
05 04 14 -66 26.1 NGC 1818 = KMHK 491
05 30 40 -67 17.2 NGC 2004 = KMHK 991
05 42 08 -69 12.7 NGC 2100 = KMHK 1257
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 90 2859 *Photometry for NGC 330
table3.dat 92 852 Photometry for NGC 1818
table4.dat 90 1390 Photometry for NGC 2004
table5.dat 86 1037 Photometry for NGC 2100
table7a.dat 86 476 Grid of colors and bolometric corrections for
solar abundance
table7b.dat 86 410 Grid of colors and bolometric corrections for
[Fe/H] = -0.5
table7c.dat 86 409 Grid of colors and bolometric corrections for
[Fe/H] = -1.0
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Note on table2.dat : some entries were added after the publication,
see the "History" section below
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See also:
J/A+AS/108/571 : Photometry of the SMC cluster NGC 330 (Vallenari+, 1994)
J/MNRAS/260/782 : CCD photometry of NGC 2004 and 2100 (Balona+ 1993)
Byte-by-byte Description of file: table[2345].dat
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Bytes Format Units Label Explanations
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1 A1 --- Chip WFPC chip star is on
3- 6 I4 --- Number Star number
8- 13 F6.2 pix Xpix X pixel position
16- 21 F6.2 pix Ypix Y pixel position
24- 29 F6.3 mag F555 ? Magnitude in the F555W filter
32- 37 F6.3 mag F160 ? Magnitude in the F160BW filter
40- 45 F6.3 mag F656 ? Magnitude in the F656N filter
48- 53 F6.3 mag 160-555 ? The F160BW - F555W color
56- 61 F6.3 mag 555-656 ? The F555W - F656N color
64- 68 F5.3 [K] Log(T) ? Log of the effective temperature
72- 76 F5.3 [solLum] Log(L) ? Log of the luminosity in solar units
80- 94 A15 --- ID Other identifications (1)
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Note (1): Identifiers with prefixes A, B, C, and D are the designations
according to Robertson (1974A&AS...15..261R 1974A&AS...15..261R), those with prefix SW are
from Sebo & Wood (1994AJ....108..932S 1994AJ....108..932S), and those with prefix KWB are
from Keller et al. (1999A&AS..134..489K 1999A&AS..134..489K).
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Byte-by-byte Description of file: table7*.dat
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Bytes Format Units Label Explanations
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1- 5 I5 K Teff Effective Temperature
9- 12 F4.2 [cm/s2] log(g) Log of the surface gravity
17- 23 F7.3 mag Mbol Bolometric magnitude (1)
25- 30 F6.3 mag BC Bolometric correction at F555W filter (1)
33- 38 F6.3 mag F555 Magnitude of the F555W filter (1)
41- 46 F6.3 mag 160-555 The F160BW-F555W color (1)
49- 54 F6.3 mag 336-555 The F336W-F555W color (1)
57- 62 F6.3 mag 439-555 The F439W-F555W color (1)
65- 70 F6.3 mag 450-555 The F450W-F555W color (1)
73- 78 F6.3 mag 675-555 The F675W-F555W color (1)
81- 86 F6.3 mag 814-555 The F814W-F555W color (1)
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Note (1): zero points adjusted to produce 0.04mag for all bands with the
Castelli & Kurucz (1994A&A...281..817C 1994A&A...281..817C, see </J/A+A/281/817>)
spectrum of Vega
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History:
* 18-Apr-2000: From AJ electronic edition
* 12-Jul-2000: following a message from the author ()
to CDS (Francois Ochsenbein), 9 more entries were added to table2
(photometry for NGC 330):
on Chip#3, Numbers 15, 16, 20, 36, 41, 54, 58, 129;
on Chip#4, Number 78.
(End) Greg Schwarz [AAS] 12-Jul-2000