Preliminary Sunyaev Zel'dovich Observations of Galaxy Clusters with OCRA-p

TL;DR

This paper reports successful 30 GHz Sunyaev Zel'dovich observations of four galaxy clusters using the OCRA-p instrument, demonstrating its effectiveness and potential for future SZ studies.

Contribution

First successful SZ observations of galaxy clusters with OCRA-p, showcasing its capability and efficiency for future research.

Findings

All four clusters detected with 4-6 sigma significance.

Measured temperature decrements agree with literature.

Systematic effects effectively suppressed.

Abstract

We present 30 GHz Sunyaev Zel'dovich (SZ) observations of a sample of four galaxy clusters with a prototype of the One Centimetre Receiver Array (OCRA-p) which is mounted on the Torun 32-m telescope. The clusters (Cl0016+16, MS0451.6-0305, MS1054.4-0321 and Abell 2218) are popular SZ targets and serve as commissioning observations. All four are detected with clear significance (4-6 sigma) and values for the central temperature decrements are in good agreement with measurements reported in the literature. We believe that systematic effects are successfully suppressed by our observing strategy. The relatively short integration times required to obtain these results demonstrate the power of OCRA-p and its successors for future SZ studies.