THE HYADES-AGE OPEN STAR CLUSTERS NGC 6633 AND IC 4756

We propose deep EPIC surveys of the Hyadesage open star clusters NGC 6633 andIC 4756. These are the only such clusters with relatively small angular diameter(less than about 1 deg.) within 800 pc. The 50ks exposures will reach below themedian Xray luminosities seen in the Hyades, even for dM stars, and (1) allowdefinitive inter and intracluster comparisons; (2) probe the magnetic dynamodown to at least midM in each cluster. The NGC 6633 observations willcomplement our ongoing optical programme; we have now surveyed the cluster tolateM. NGC 6633 is the most ironpoor of the Hyadesage clusters and hence themost crucial when looking for composition effects. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]