INTERFEROMETRIC IMAGING OF THE SUNYAEV-ZELDOVICH EFFECT AT 30 GHz

摘要

We present high signal-to-noise ratio images of the Sunyaev-Zeldovich effect toward the clusters CL 0016+16 and Abell 773. A null result is reported for Abell 1704. The data were obtained with the millimeter array of the Owens Valley Radio Observatory outfitted with 30 GHz receivers. Isothermal models for the cluster gas with core radii spanning 20″-100″ were fitted to the visibility data. The results suggest the central decrement ΔT_0 lies within the range -700 to -820 μK for CL 0016+16 and -575 to -760 μK for Abell 773, corresponding to Compton y-values of 1.3-1.5 X 10~(-4) and 1.1-1.4 X 10~(-4), respectively. A comparison of the image of the Sunyaev-Zeldovich effect toward CL 0016+16 with a ROSAT image of the X-ray emission shows good correspondence; the positions agree within the uncertainties, and both images show resolved structure elongated at a position angle of ～50°. Using the core radius and ellipticity derived from the X-ray data to constrain the model parameters resulted in a decrement for CL 0016+16 of ΔT_0 = -717 ± 65 μK.