We present a photometric study of the globular clusters in the giant elliptical galaxy M60 in the Virgo cluster , based on deep , relatively wide field Washington CT _ { 1 } CCD images .
The color-magnitude diagram reveals a significant population of globular clusters in M60 , and a large number of young luminous clusters in NGC 4647 , a small companion spiral galaxy north-west of M60 .
The color distribution of the globular clusters in M60 is clearly bimodal , with a blue peak at ( C - T _ { 1 } ) = 1.37 , and a red peak at ( C - T _ { 1 } ) = 1.87 .
We derive two new transformation relations between the ( C - T _ { 1 } ) _ { 0 } color and [ Fe/H ] using the data for the globular clusters in our Galaxy and M49 .
Using these relations we derive the metallicity distribution of the globular clusters in M60 , which is also bimodal : a dominant metal-poor component with center at [ Fe/H ] = -1.2 , and a weaker metal-rich component with center at [ Fe/H ] = -0.2 .
The radial number density profile of the globular clusters is more extended than that of the stellar halo , and the radial number density profile of the blue globular clusters is more extended than that of the red globular clusters .
The number density maps of the globular clusters show that the spatial distribution of the blue globular clusters is roughly circular , while that of the red globular cluster is elongated similarly to that of the stellar halo .
We estimate the total number of the globular clusters in M60 to be 3600 \pm 500 , and the specific frequency to be S _ { N } = 3.8 \pm 0.4 .
The mean color of the bright blue globular clusters gets redder as they get brighter in both the inner and outer region of M60 .
This blue tilt is seen also in the outer region of M49 , the brightest Virgo galaxy .
Implications of these results are discussed .