RT Journal Article T1 Fine structure in the large n limit of the non-hermitian Penner matrix model A1 Álvarez, Gabriel A1 Martínez Alonso, Luis A1 Medina Reus, Elena AB In this paper we apply results on the asymptotic zero distribution of the Laguerre polynomials to discuss generalizations of the standard large n limit in the non-hermitian Penner matrix model. In these generalizations g_(n)n → t, but the product g_(n)n is not necessarily fixed to the value of the ’t Hooft coupling t. If t > 1 and the limit l = lim_(n→∞) |sin(π/g_n)| ^(1/n) exists, then the large n limit is well-defined but depends both on t and on l. This result implies that for t > 1 the standard large n limit with g_(n)n = t fixed is not well-defined. The parameter l determines a fine structure of the asymptotic eigenvalue support: for l ≠ 0 the support consists of an interval on the real axis with charge fraction Q = 1 − 1/t and an l-dependent oval around the origin with charge fraction 1/t. For l = 1 these two components meet, and for l = 0 the oval collapses to the origin. We also calculate the total electrostatic energy Ԑ which turns out to be independent of l, and the free energy Ƒ = Ԑ - Ǫ ln l, which does depend of the fine structure parameter l. The existence of large n asymptotic expansions of Ƒ beyond the planar limit as well as the double-scaling limit are also discussed. PB Academic Press Inc Elsevier Science SN 0003-4916 YR 2015 FD 2015-10 LK https://hdl.handle.net/20.500.14352/24167 UL https://hdl.handle.net/20.500.14352/24167 LA eng NO © Academic Press Inc Elsevier Science.We thank Prof. A. Martínez Finkelshtein for calling our attention to many nice results on zero asymptotics of Laguerre polynomials. The financial support of the Ministerio de Ciencia e Innovación under project FIS2011-22566 is gratefully acknowledged. NO Ministerio de Ciencia e Innovación DS Docta Complutense RD 9 abr 2025