Abstract:

By making all-sky observations of 21-cm flux at redshifts near one, the large scale structure of the Universe can be mapped in three dimensions. This can be accomplished by studying specific intensity with resolution ~ 10 Mpc, rather than via the usual galaxy redshift survey. This new technique is called intensity mapping. A new type of radio telescope based on fixed cylinders has been proposed for these observations, and I will report the progress of the testing of a prototype cylinder telescope built in Pittsburgh. The primary goal of the program is to detail the expansion history, in order to constrain dark energy models. To accomplish this the telescope will have mapping speed about 1000 times faster than any current radio telescope. This means the telescope will also provide a rich set of synoptic data.