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
Instrument
LWS01 , PHT03 , PHT22 , PHT40 , SWS02
Temporal Coverage
1996-08-16T08:34:05Z/1998-02-05T23:32:54Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, LAUREIJS et al., 1999, 'Infrared Properties of Compact Sources in the Magellanic Clouds ', 1.0, European Space Agency, https://doi.org/10.5270/esa-pv0q6jy
