WUNA Lunch Talk:

Carl Ferkinhoff and Drew Brisben

Cornell University

FIR Fine Structure lines from Early Galaxies with ZEUS

April 10

12:10PM, Room 230, NRAO, Edgemont Road


The High Redshift (z) Early Universe Spectrometer (ZEUS), is a bolometer-based echelle grating spectrometer. Designed to observe through the 350 and 450 um transmission windows in the Earth's atmosphere, this instrument has proven to be a highly effective probe of redshifted FIR fine structure lines originating in PDRs and ionized gas of high redshift galaxies.

The [CII] line is typically the single brightest line from star forming galaxies and is both an important coolant for the ISM and a sensitive probe of the strength of the ambient far-UV field. We have now detected this line in 20 galaxies, representing a major fraction of the known high-z [CII] sources. Our [CII] data is supplemented with Herschel and Spitzer data, yielding high quality spectral energy distributions (SEDs) and insight into star formation rates and the presence of AGN components.

In addition to the [CII] line detections, using ZEUS we have also detected the [OIII] 88 micron and [NII] 122 micron lines from a handful of of high-z galaxies. These lines, can be similarly bright as the [CII], but arise only in ionized regions. Their relative strength is an excellent probe of the hardness of the ionizing radiation field.

Recently we commissioned the 2nd generation High Redshift (z) Early Universe Spectrometer (ZEUS-2) on the Atacama Pathfinder Experiment (APEX). With improved sensitivity, reduced operating costs, and broader wavelength coverage than the first ZEUS, ZEUS-2 enables continued exploration of the FIR fine structure lines from Early Galaxies. Our current and future work provides excellent targets for detailed follow-up with ALMA.