Precision physics with heavy quarks: from colliders to the cosmos


The charm, beauty and top quarks are among the heaviest of the known fundamental particles of nature. Due to their large mass, the production of these particles requires large amounts of input energy, such as that provided through the collision of high energy protons. Such a process occurs naturally as high energy cosmic rays bombard the Earth's upper atmosphere, or at high energy colliders such as the Large Hadron Collider (LHC).

At the LHC, heavy quarks are produced in copious amounts, and precision studies of their production rates can provide detailed information on the inner structure of the colliding protons. In addition to improving our understanding of proton structure, such information also has important consequences for neutrino astronomy, as for example, the production and decay of heavy quarks in the atmosphere constitutes a main background for measurements of ultra high energy cosmic neutrinos at experiments such as IceCube.

The goal of this VENI proposal is to perform a detailed study of charm quark production and fragmentation into charm hadrons at the LHC. In doing so, substantial improvements in the global analysis of proton structure will be made.
Special attention will be paid to the role of an intrinsic charm contribution within the proton, and how this affects the rates of charm quark production at the LHC as well as the Earth's upper atmosphere. It is also the aim of this project to address the question of the universality of heavy quark fragmentation. This can be achieved by comparing the fragmentation observed in the hadronic LHC environment with respect to that which occurs in a clean $e^+e^-$ environment.


Project number


Main applicant

Dr. R.G. Gauld

Affiliated with

ETH Zurich, Departement Physik, Institute for Theoretical Physics


01/01/2018 to 01/01/2021