Datatype: hk

This datatype (hk) collects the photoelectric photometric observations of stars in open clusters made with the combination of Strögrem and the Ca filters measuring the CaII HK line forming the Caby system. The hk parameter is defined by : hk = (Ca - b) (b - y) by Twarog et al. 1991.

CCD Caby observations are recorded under the hkccd datatype.

Record structure

No:Star number
Ref:Reference
V:V magnitude
b-y:b-y colour index
hk:hk parameter
N:Number of measurements

Database access

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Last Update: 16 April 2006