TY - JOUR

T1 - Conformal vs confining scenario in SU(2) with adjoint fermions

AU - Debbio, LD

AU - Lucini, B.

AU - Patella, A.

AU - Pica, C.

AU - Rago, A.

PY - 2009/10/26

Y1 - 2009/10/26

N2 - The masses of the lowest-lying states in the meson and in the gluonic sector
of an SU(2) gauge theory with two Dirac flavors in the adjoint representation
are measured on the lattice at a fixed value of the lattice coupling $\beta =
4/g_0^2 = 2.25$ for values of the bare fermion mass $m_0$ that span a range
between the quenched regime and the massless limit, and for various lattice
volumes. Even for light constituent fermions the lightest glueballs are found
to be lighter than the lightest mesons. Moreover, the string tension between
two static fundamental sources strongly depends on the mass of the dynamical
fermions and becomes of the order of the inverse squared lattice linear size
before the chiral limit is reached. The implications of these findings for the
phase of the theory in the massless limit are discussed and a strategy for
discriminating between the (near--)conformal and the confining scenario is
outlined.

AB - The masses of the lowest-lying states in the meson and in the gluonic sector
of an SU(2) gauge theory with two Dirac flavors in the adjoint representation
are measured on the lattice at a fixed value of the lattice coupling $\beta =
4/g_0^2 = 2.25$ for values of the bare fermion mass $m_0$ that span a range
between the quenched regime and the massless limit, and for various lattice
volumes. Even for light constituent fermions the lightest glueballs are found
to be lighter than the lightest mesons. Moreover, the string tension between
two static fundamental sources strongly depends on the mass of the dynamical
fermions and becomes of the order of the inverse squared lattice linear size
before the chiral limit is reached. The implications of these findings for the
phase of the theory in the massless limit are discussed and a strategy for
discriminating between the (near--)conformal and the confining scenario is
outlined.

U2 - 10.1103/PhysRevD.80.074507

DO - 10.1103/PhysRevD.80.074507

M3 - Article

VL - 80

JO - Phys.Rev.D80:074507,2009

JF - Phys.Rev.D80:074507,2009

IS - 7

ER -