We have investigated the properties of the diffuse light in the Virgo cluster core region , based on the detection of intracluster planetary nebulae ( PNe ) in four fields .
We eliminate the bias from misclassified faint continuum objects , using improved Monte Carlo simulations , and the contaminations by high redshift Ly \alpha galaxies , using the Ly \alpha luminosity function in blank fields .
Recent spectroscopic observations confirm that our photometric PN samples are well-understood .
We find that the diffuse stellar population in the Virgo core region is inhomogeneous on scales of 30 ^ { \prime } -90 ^ { \prime } : there exist significant field-to-field variations in the number density of PNe and the inferred amount of intracluster light , with some empty fields , some fields dominated by extended Virgo galaxy halos , and some fields dominated by the true intracluster component .
There is no clear trend with distance from M87 .
The mean surface luminosity density , its rms variation , and the mean surface brightness of diffuse light in our 4 fields are \Sigma _ { B } = 2.7 \times 10 ^ { 6 } L _ { B \odot } arcmin ^ { -2 } , \mbox { rms } = 2.1 \times 10 ^ { 6 } L _ { B \odot } arcmin ^ { -2 } , and \bar { \mu } _ { B } = 29.0 mag arcsec ^ { -2 } respectively .
Our results indicate that the Virgo cluster is a dynamically young environment , and that the intracluster component is associated at least partially with local physical processes like galaxy interactions or harassment .
We also argue , based on kinematic evidence , that the so-called ’ over-luminous ’ PNe in the halo of M84 are dynamically associated with this galaxy , and must thus be brighter than and part of a different stellar population from the normal PN population in elliptical galaxies .