CCD photometry on the intermediate-band uvbyCa H \beta system is presented for the anticenter , intermediate-age open cluster , Melotte 71 .
Restricting the data to probable single members of the cluster using the color-magnitude diagram and the photometric indices alone generates a sample of 48 F dwarfs on the unevolved main sequence .
The average E ( b - y ) = 0.148 \pm 0.003 ( s.e.m . )
or E ( B - V ) = 0.202 \pm 0.004 ( s.e.m .
) , where the errors refer to internal errors alone .
With this reddening , [ Fe/H ] is derived from both m _ { 1 } and hk , using H \beta and b - y as the temperature index , with excellent agreement among the four approaches and a final weighted average of [ Fe/H ] = –0.17 \pm 0.02 ( s.e.m . )
for the cluster , on a scale where the Hyades has [ Fe/H ] = +0.12 .
When adjusted for the higher reddening estimate , the previous metallicity estimates from Washington photometry and from spectroscopy are now in agreement with the intermediate-band result .
From comparisons to isochrones of appropriate metallicity , the cluster age and distance are determined as 0.9 \pm 0.1 Gyr and ( m - M ) = 12.2 \pm 0.1 or ( m - M ) _ { 0 } = 11.6 \pm 0.1 .
At this distance from the sun , Mel 71 has a galactocentric distance of 10.0 kpc on a scale where the sun is 8.5 kpc from the galactic center .
Based upon its age , distance , and elemental abundances , Mel 71 appears to be a less populous analog to NGC 3960 .