Datatype: Wal
The Walraven system has the unique feature that the magnitude
and the colour indices are given in logarithm of the intensity and not in
units of magnitude as is the practice for all other systems.
It has two filters on the ultraviolet side of the Balmer discontinuity
(U and W) which offers interesting possibilities for the analysis of
early type stars.
Most open clusters observed in this system are in the southern sky.
Some are equatorial objects.
The relations of the Walraven Vw and (V-B) indices (La Silla system)
with V and (B-V) in the UBV system are:
- Vubv = 6.885 - 2.5 [Vw + 0.030 (V-B)]
- (B-V)ubv = 2.571 (V-B) - 1.020 (V-B)**2 + 0.500 (V-B)**3 - 0.01
Record structure
No | : | Star number |
Ref | : | Data source |
V | : | V magnitude (Johnson system) |
Vw | : | Walraven V magnitude |
V-B | : | V-B colour index |
B-U | : | B-U colour index |
U-W | : | U-W colour index |
B-L | : | B-L colour index |
N | : | Number of measurements |
Database access
List of clusters
Query the references
Jean-Claude.Mermilliod@obs.unige.ch
Last Update: 17 February 1998