Hadron masses in QCD with one quark flavour

Abstract

One-flavour QCD -a gauge theory with SU(3) colour gauge group and a fermion in the fundamental representation -is studied by Monte Carlo simulations. The mass spectrum of hadronic bound states is investigated in a volume with extensions of L ≃ 4.4 r 0 (≃ 2.2 fm) at two different lattice spacings: a ≃ 0.37 r 0 (≃ 0.19 fm) and a ≃ 0.27 r 0 (≃ 0.13 fm). The lattice action is Symanzik tree-level-improved Wilson action for the gauge field and (unimproved) Wilson action for the fermion.

The gluino-glue particle and finite size effects in supersymmetric Yang-Mills theory

“…The a-π is not a physical particle in SYM, which only contains one Majorana fermion. However, it can be defined in a partially quenched setup, in which the model is supplemented by a second species of gluinos and the corresponding bosonic ghost gluinos, in the same way as for one-flavour QCD [13].…”

The mass of the adjoint pion in $ \mathcal{N} $ = 1 supersymmetric Yang-Mills theory

“…In practice the a-π is being used for tuning since it yields a more precise signal than the supersymmetric Ward identities. It is the purpose of this article to demonstrate that the adjoint pion can be defined in a partially quenched setup, in which the model is supplemented by a second species of gluinos and the corresponding bosonic ghost gluinos, in the same way as for one-flavour QCD [9], and to show that the behaviour indicated in eq. (3) is indeed found in partially quenched chiral perturbation theory.…”

QCD with one quark flavor: II. Analysis and chiral perturbation theory

“…A correction factor C[U] in the measurement is associated with configurations for which eigenvalues of the (squared Hermitian) fermion matrix Q 2 [U] lie outside the validity interval of the polynomial approximation. We refer to [10] for more details on the algorithmic setup.…”

“…Another important place where relics of SUSY in N f = 1 QCD can be investigated, considered in more detail in this contribution, is the low-lying bound-state spectrum [10]. In SYM the mass patterns are strongly constrained by SUSY.…”

“…As we have argued in [10], it is useful to embed the N f = 1 QCD theory in a partially quenched theory with additional quark flavors. A particularly symmetric choice consists in taking the (N V ) valence quark flavors degenerate with the sea quark: in this case the combined sea and valence sector is characterized by an exact SU(N V +1) flavor symmetry.…”