rowan-robinson et al. (1991) discovered a hyperluminous (l = 10e14 lsun) galaxy, iras f10214+4724, at redshift of 2.286, among the sources in the iras faint source catalogue. since this object contains abundant molecular gas (10e11 msun: brown & vanden bout 1991; solomon, radford, & downes 1992), it has been sometimes considered as a possible candidate of proto galaxies (cf. elbaz et al. 1992). the optical spectrophotometry has revealed that the nuclear light is strongly polarized (17%: jannuzi et al. 1994), suggesting the presence of hidden agn. even though the presence of agn, iras f10214+4724 is one of very important objects to study forming galaxies because of its high redshift and the unusually abundant molecular gas. in order to understand the true nature of this kind of hyperluminous infrared galaxies (hypers), we have to measure their star formation activity unambiguously. here we propose to use pah features observed in near and mid infrared wavelength regions because they are intimately related to the star formation activity. the pah features observed at 3.28, 3.4, 6.2, 7.7, 8.6, and 11.25 microns are considered as due to transient heating of polycyclic hydrocarbon molecules by uv photons emitted by ob stars (leger & puget 1984). these emission features are indeed not observed in pure agn like type 1 seyfert and qsos because pahs are destroyed by hard radiation field of agn (aitken & roche 1985; voit 1992) while observed ubiquitously in starburst galaxies, giving good measures of the star forming activity (moorwood 1986; mouri et al. 1990; mizutani, suto, & maihara 1994). therefore, we will be able to understand the star-forming nature of hypers. our targets are (1) iras f10214+4724 (z=2.286: rowan-robinson et al. 1991), (2) iras f15307+3252 (z=0.925: cutri et al. 1994), and (3) iras 09104+4109 (z=0.442: kleinmann et al. 1988). since the three objects have a wide ran...ge of redshift from 0.442 to 2.286, the interesting pah features are observed at 10 - 15 microns. thus, we need the isocam cvf system to perform this observation.
Instrument
CAM04
Temporal Coverage
1996-04-08T00:56:50Z/1996-04-10T02:24:12Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the world's 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.
