N = 1 SQCD-like theories with Nf massive flavors from AdS/CFT and β functions

Abstract

We study new supergravity solutions related to large-Nc N = 1 supersymmetric gauge field theories with a large number Nf of massive flavors. We use a recently proposed framework based on configurations with Nc color D5 branes and a distribution of Nf flavor D5 branes, governed by a function NfS(r). Although the system admits many solutions, under plausible physical assumptions the relevant solution is uniquely determined for each value of x ≡ Nf/Nc. In the IR region, the solution smoothly approaches the deformed Maldacena-Núñez solution. In the UV region it approaches a linear dilaton solution. For x < 2 the gauge coupling βg function computed holographically is negative definite, in the UV approaching the NSVZ β function with anomalous dimension γ0 = -1/2 (approaching -3/(32π2)(2Nc-Nf)g3)), and with βg → -∞ in the IR. For x = 2, βg has a UV fixed point at strong coupling, suggesting the existence of an IR fixed point at a lower value of the coupling. We argue that the solutions with x > 2 describe a "Seiberg dual" picture where Nf - 2N c flips sign. © SISSA 2011.