Event shape observables explained

In high energy physics, event shapes observables are quantities used to characterize the geometry of the outcome of a collision between high energy particles in a collider. Specifically, event shapes observables quantify the general pattern traced by the trajectories of the particles resulting from the collision.^{[1] [2]}

The most common event shape observables include:

• The sphericity;
• The aplanarity;
• The thrust.
• The C-parameter;
• The jet broadening.

Notes and References

1. V. D. Barger, R. J. N. Phillips (1997) “Collider Physics” Frontier in Physics, Addison-Wesley Publishing Company, Inc.
2. M. Dasgupta and G. P. Salam (2004),Event shapes in e+ e- annihilation and deep inelastic scattering,J. Phys. G 30, R143, preprint