First Results

Herschel

Here we present our first results from the Herschel data obtained during the science demonstration phase. These results have been published as part of the Herschel Special Issue in Astronomy & Astrophysics.

SDSS J1148+5251: At a redshift of z = 6.42 this is one of the highest redshift quasars known and the highest redshift quasars in our sample. We were able to detect this source at 100 and 160 μm with PACS in the science demonstration data. This still represents the redshift record for Herschel detected objects. During later observations, we detected this object also in the remaining Herschel bands: at 70 μm with PACS and at 250+350+500 μm with SPIRE. Below we show all Herschel maps of this quasar plus a collection of some Spitzer images. The maps in the first two rows are 2 arc minutes on a side and North is up with East to the left. Due to the lower resolution of the the SPIRE maps, we show 3 arcminute wide images at these wavelengths.

With the photometry from these new maps at far infrared wavelengths, we can now build an UV/optical thru infrared SED of unprecedented coverage at such high redshifts. From the SEDs, a secondary peak due to star formation is clearly visible in the far infrared. In a next step we will perform multi-component fitting of the SED in order to determine important parameters of the AGN powered and star formation powered emission.

Spitzer

All objects in the Herschel sample were also observed with the Spitzer IRAC and MIPS instruments at 3.6, 4.5, 5.8, 8.0, and 24 μm. All data have been analysed and all QSOs have been detected in all filters. A few examples are shown below:

SDSS J0338+0021 @ z = 5.03 and z-mag(AB) = 19.70

SDSS J161705.69+443522.6 @ z = 5.49 and z-mag(AB) = 18.58

PKS1937-101 @ z = 3.79 (from the radio/mm-loud QSO sample) and Opt-mag(AB)=19.0