An Estimate of the K-ratio in a sample of 27 Galaxy Clusters.
Galaxy Clusters Near and Far
Therese Cantwell
University of Manchester
Anna Scaife (University of Manchester), Judith Croston (University of Cambridge,University of Southampton)
The discovery of Mpc scale diffuse radio emission was the first evidence for non thermal particles in galaxy clusters, as well as evidence for cluster scale magnetic fields. However calculating both the non-thermal fraction of the intracluster medium and the magnetic field is non trivial. The most common assumption used when estimating a lower limit on magnetic field strengths in galaxy clusters is equipartition, which relies on prior knowledge of the ratio of cosmic ray protons to cosmic ray electrons, Kp/e. To date this Kp/e has not been well constrained theoretically or observationally for galaxy clusters. Combinations of SZ, X-ray and gamma ray observations offer a powerful probe into Kp/e.I will present the preliminary results from a survey of 27 galaxy clusters with the Arcminute Microkelvin Imager (AMI) which aims to characterize Kp/e in both cool core and non-cool core clusters. These clusters are a subset of the HIghest X-ray FLUx Galaxy Cluster Sample (HIFLUGCS) which have gamma ray upper limits.


13:30 - 15:00
EX - LT3 (320)