Documentation

EpsilonEridani.Particles.Parton.Species

Parton species and their charge conjugation #

For a hadron whose quarks come in the flavours of a type Flavor, the parton species are the quark and the antiquark of each flavour and the gluon. This file names that index type, Species Flavor, so that the quark, antiquark and gluon distributions of a hadron (collinear densities, TMDs, fragmentation functions) are indexed by one type, and a species sum such as the momentum sum rule ∑ₛ ∫₀¹ x fₛ(x) dx = 1 runs over all of them, the gluon included.

Charge conjugation exchanges the quark and the antiquark of each flavour and fixes the gluon (Species.conj); it is an involution.

Main definitions #

Main statements #

References #

A parton species over the quark-flavour type Flavor: the quark of a flavour, the antiquark of a flavour, or the gluon.

  • quark {Flavor : Type} (i : Flavor) : Species Flavor

    The quark of flavour i.

  • antiquark {Flavor : Type} (i : Flavor) : Species Flavor

    The antiquark of flavour i.

  • gluon {Flavor : Type} : Species Flavor

    The gluon.

Instances For

    The species over Flavor are equivalent to (Flavor ⊕ Flavor) ⊕ Unit: the quark of flavour i goes to .inl (.inl i), the antiquark of flavour i to .inl (.inr i), and the gluon to .inr (). It carries the Fintype instance on species and sum_univ.

    Equations
    • One or more equations did not get rendered due to their size.
    Instances For
      @[simp]

      There are two species, a quark and an antiquark, for each flavour, and the gluon.

      theorem EpsilonEridani.Particles.Parton.Species.sum_univ {Flavor : Type} [Fintype Flavor] {M : Type u_1} [AddCommMonoid M] (g : Species Flavor → M) :
      ∑ s : Species Flavor, g s = ∑ i : Flavor, g (quark i) + ∑ i : Flavor, g (antiquark i) + g gluon

      A sum over all parton species is the sum over the quarks, the sum over the antiquarks, and the gluon term.

      @[simp]