ADC/CDS Standard Document for Catalog:/journal_tables/AJ/113/1691/
ADC/CDS Standard Document for Catalog:| 1. Use the ADC Data Viewer Suite to visualize the data. |
|
| 2. Get the data files via anonymous FTP. (See Note.) |
|
J/AJ/113/1691 Stars in R136 (Hunter+ 1997)
================================================================================
Ultraviolet Photometry of Stars in the Compact Cluster R136
in the Large Magellanic Cloud
Hunter D.A., Vacca W.D., Massey P., Lynds R., O'Neil E.J.
<Astron. J. 113, 1691 (1997)>
=1997AJ....113.1691H
================================================================================
ADC_Keywords: Photometry, ultraviolet
Mission_Name: HST
Abstract:
We present ultraviolet photometry of stars in the Large Magellanic
Cloud star cluster R136. The data were obtained with the refurbished
Wide Field/Planetary Camera on the Hubble Space Telescope through an
ultraviolet filter centered at 1750A (F170W). These data, combined
with optical HST observations presented previously, are used to
explore the hot, luminous stellar population within the cluster. The
first question we wanted to address was whether the ultraviolet could
place better constraints on differential reddening and the degree of
coevality within the cluster than optical photometry alone. The
stellar sequence in the color magnitude diagram using the F170W-F555W
color is broader than it was in the optical and is broader than would
be expected from photometric uncertainties. Although there could be a
modest age spread among the massive stars, a large part of the
intrinsic spread in the color-magnitude diagram is likely to be due to
reddening differences. There is also some evidence that stars in the
outer parts of the cluster are affected by a larger range in reddening
than those in the smaller region of the cluster core. The second
question we addressed is whether ultraviolet photometry in combination
with optical photometry can distinguish the most massive stars more
readily than is possible with the optical colors. The F170W-F555W
color is better at separating B supergiants, of which there is only
one in R136, from comparably bright O and Wolf-Rayet stars. However,
spectral classifications of the stars within R136 will be necessary to
properly identify stellar types of the rest of the stars and to
disentangle age and reddening effects.
(Copyright) 1997 American Astronomical Society.
Objects:
----------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------
05 38 42.8 -69 06 03 R 136 = RMC 136 = HD 38268
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 74 650 The cluster photometry
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- Star Star identification number
6- 11 F6.1 pix Xpos X pixel coordinate
13- 18 F6.1 pix Ypos Y pixel coordinate
20- 25 F6.2 mag F170W F170W magnitude
27- 32 F6.2 mag e_F170W Error in F170W
34- 39 F6.2 mag F555W ?=100.00 F555W magnitude
41- 46 F6.2 mag e_F555W ?=100.00 Error in F555W
48- 53 F6.2 mag F170W-F555W ?=100.00 F170W-F555W color
55- 60 F6.2 mag e_F170W-F555W ?=100.00 Error in F170W-F555W
62- 67 F6.2 mag F336W-F555W ?=100.00 F336W-F555W color
69- 74 F6.2 mag e_F336W-F555W ?=100.00 Error in F336W-F555W
--------------------------------------------------------------------------------
Origin: AAS CD-ROM series, Volume 8, 1997 Lee Brotzman [ADS] 02-May-1997
================================================================================
(End) [CDS] 04-Jul-1997