We report the first detection of a Sunyaev–Zel ’ dovich ( S–Z ) decrement with the Arcminute Microkelvin Imager ( AMI ) .
We have made commissioning observations towards the cluster A1914 and have measured an integrated flux density of -8.61 mJy in a uv -tapered map with noise level 0.19 mJy/beam .
We find that the spectrum of the decrement , measured in the six channels between 13.5–18 GHz , is consistent with that expected for a S–Z effect .
The sensitivity of the telescope is consistent with the figures used in our simulations of cluster surveys with AMI .