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INTEGRAL is an optical fiber unit for performing 2D spectroscopy ofextended objects at the 4.2m. William Herschel Telescope (WHT). It is mounted at the GHRIL Nasmyth focus together with newly built acquisition, guiding, and calibration units. It makes use of the specially designed fiber spectrograph WYFFOS. This system allows up to six bundles to be mounted simultaneously. It currently contains three science oriented fiber bundles, any one of which can be easily and quickly placed in the telescope beam. Their spatial resolution elements (fiber core diameters) are O".45, O".9, and 2".T, respectively. Hence, depending on the prevailing seeing conditions the instrument can be easily optimized for the scientific program. INTEGRAL was succesfully commissioned at the WilT during a six night period in July 1997. Here we will discuss its main characteristics.

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Abstract. This work is based on the rst results from a systematic search for high redshift Type Ia supernovae. Using lters in the R-band we discovered seven such SNe, with redshift z = 0 :3 , 0:5, before or at maximum light. Type Ia SNe are known to be a homogeneous group of SNe, to rst order, with very similar light curves, spectra and peak luminosities. In this talk we report that the light curves we observe are all broadened time dilated as expected from the expanding universe hypothesis. Small variations from the expected 1 + z broadening of the light curve widths can be attributed to a width-brightness correlation that has been observed for nearby SNe z 0:1. We show in this talk the rst clear observation of the cosmological time dilation for macroscopic objects.