  Based on PYTHIA6.428, event-by-event fluctuations of the mean transverse
momentum in proton- proton collisions at sqrt_s = 7 TeV are studied using
several measures of the fluctuations. The study compares results of the
fluctuations for events where color reconnection is turned on, with those where
color reconnection is turned off. The comparison reveals that some of the
fluctuation measures are much more sensitive to color reconnection than others.
Through the comparison it is demonstrated for the first time that for
proton-proton collisions at the Large Hadron Collider, these sensitive measures
of the mean transverse momentum fluctuations can serve as alternative probes to
color reconnection and color reconnection is a non-trivial source of the
event-by-event fluctuations.
