Unknown raptor, Goshawk maybe?

[eddiehing]

OK calling to anyone who knows their birds as i'm stuck with this one. I live in Inkpen (berks) and heard a raven out the back (a very recently new visitor), found him at top of tree then he went after a raptor that was thermalling and mobbed it. The raptor was brownish, 2/3rds the size of the raven, had a round tail and thickish wings but was not a buzzard (was smaller and not as chunky). It generally circled above the raven then dive bombed it repeatedly but the raven continued it's pursuit, did a lot more flapping but was def in pursuit for about 5 mins until they were both quite high and raptor shot off at 45 degrees at speed, to lose the raven I guess, but it followed. Then I lost sight. Great to watch both were very agile. I cannot work out what the raptor was though, it's the fanned tail that's thrown me, the goshawk has a srtaight tail when it flies normally from what I have read online? Having never knowingly seen one before I don't know for sure. Def was not a kestrel (way bigger) or buzzard (smaller, less chunky) however shape wise was closest to these two. Any ideas anyone?!

[RoyW]

Sparrowhawk sounds most likely (if it definitely wasn't some sort of falcon).
Goshawks are more or less the same size as Buzzards - or roughly the same size as a Raven.
Tail shape in raptors can appear very different depending on whether the tail is spread, or closed.

[accipter]

most likely a large female sparrowhawk or maybe a lost harris hawk. Alan.