  We study observables in a conformal field theory which are very closely
related to the ones used to describe hadronic events at colliders. We focus on
the correlation functions of the energies deposited on calorimeters placed at a
large distance from the collision. We consider initial states produced by an
operator insertion and we study some general properties of the energy
correlation functions for conformal field theories. We argue that the small
angle singularities of energy correlation functions are controlled by the twist
of non-local light-ray operators with a definite spin. We relate the charge two
point function to a particular moment of the parton distribution functions
appearing in deep inelastic scattering. The one point energy correlation
functions are characterized by a few numbers. For ${\cal N}=1$ superconformal
theories the one point function for states created by the R-current or the
stress tensor are determined by the two parameters $a$ and $c$ characterizing
the conformal anomaly. Demanding that the measured energies are positive we get
bounds on $a/c$. We also give a prescription for computing the energy and
charge correlation functions in theories that have a gravity dual. The
prescription amounts to probing the falling string state as it crosses the
$AdS$ horizon with gravitational shock waves. In the leading, two derivative,
gravity approximation the energy is uniformly distributed on the sphere at
infinity, with no fluctuations. We compute the stringy corrections and we show
that they lead to small, non-gaussian, fluctuations in the energy distribution.
Corrections to the one point functions or antenna patterns are related to
higher derivative corrections in the bulk.
