Contents of: VI/111/./abstract/RLAUREIJ_MCCS_CP.abs

The following document lists the file abstract/RLAUREIJ_MCCS_CP.abs from catalogue VI/111.
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SCIENTIFIC ABSTRACT
As part of the ISO Magellanic Clouds coordination program, we want
to investigate the properties of a sample of peculiar compact sources
in the LMC and SMC. Although the sources appear as HII regions, they
have properties markedly different from their galactic counterparts.
With the ISO observations we want to determine the nature of the heating
sources as well as the properties of the surrounding medium.

We propose to use PHT-S to determine the NIR spectrum, particularly
the dust features which should be compared with galactic sightlines.
PHT-P and PHT-C observations are proposed to measure the FIR spectral
distribution more accurately than possible with IRAS for better
temperature estimates and to cross calibrate the spectrometers.
In addition we propose to measure the strength of the 0-0 S(0)
H2 line at 17 micron to obtain information about the cool molecular
gas. LWS measurements of a subsample of targets are proposed
to determine the presence of molecular lines of other species
as well as to study the major cooling lines of [CII] and [OI]
in the FIR.

This proposal has been coordinated with that of van der Hulst et al.
(SWS consortium) and Cox et al. (LWS consortium). Most of the
objects are included in these proposals, we will complement their
data with SWS observations of the 17 micron H2 line and PHT
observations. For those sources that do not overlap we request
additional LWS full grating scans.

OBSERVATION SUMMARY
For all objects we request concatenated P40, P03, and P22 observations
(PHT-S, P, and C) to observe in bands PHT-SS, PHT-SL, P_3.6, P_10.0,
P_16, P_20, P_25, C_60, C_70, C_135, C_200. The P03 observations will be
performed in triangular chopping mode which enables accurate determination
of the background. The chop throw is 30" and the aperture of 23"
matches the PHT-S aperture. For N160, we request a CHOPPER AVOIDANCE ANGLE
as the A1, A2, and A3 positions are aligned in north-south direction.
The P_3.6 and P_10.0 measurements are used for photometric calibration
of the PHT-S spectra. The longer wavelength (PHT-C) measurements
are performed in staring mode as the sources are much brighter
than the background in those bands. The background can still be estimated
by extrapolation of the P03 measurements.

For all lines of sight we request additional observations
with SWS (AOT S02) to accurately determine the H2 17 micron line.
For a typical source we expect a line S/N of 20 with the given
exposure times. Most of the sources will be observed with LWS by
Baluteau et al. For the ones that are not in their list we request
full grating scans (AOT L01) observations which will be concatenated
to the other observations. All objects are always visible so that the 2
target lists for spring (Galactic Centre) and autumn launch (Orion hole)
are identical.

CONCATENATION: all AOTs that should be carried out on the same
position are concatenated. This is done to ensure that the photometric
measurements have the same zodiacal background and to increase
the observational efficiency. In addition, all observations of N160A1,
A2, and A3 are concatenated, as the three objects are withing 1
arcmin from each other and because these need to be performed with a
chopper avoidance angle.

Target list
===========
Source         RA           DEC      P40/03/22  S02   L01  Pri
N81          01 07 41     -73 28 05      +       +          2
N88          01 22 55     -73 24 53      +       +          2
N145         05 28 00     -69 10 25      +       +     +    3
N159 A5      05 40 31     -69 46 09      +       +          1
30 Dor Ref*  05 39 10.4   -69 06 20      +       +     +    1
N159 AS      05 40 28     -69 48 45      +       +     +    3
N83 B        04 54 41     -69 15 39      +       +          3
N11 A        04 57 10     -66 27 54      +       +          2
N160 A1      05 39 44.1   -69 39 10      +       +          2
N160 A2      05 39 46.6   -69 38 45      +       +          2
N160 A3      05 39 44.5   -69 38 37      +       +          2

* reference source for spectrometers


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