TITLE: The vicinity of the Earth-Moon L1 point in the Bicircular Problem AUTHORS: Angel Jorba, Marc Jorba-Cusco and Jos\'e J. Rosales Universitat de Barcelona E-mails: angel@maia.ub.es, marc@maia.ub.es, rosales@maia.ub.es ABSTRACT: The Bicircular model is a periodic time dependent perturbation of the Earth-Moon Restricted Three-Body problem that includes the direct gravitational effect of the Sun on the infinitesimal particle. In this paper we focus on the dynamics in the neighbourhood of the $L_1$ point of the Earth-Moon system. By means of a periodic time dependent reduction to the centre manifold, we show the existence of two families of quasi-periodic Lyapunov orbits, one planar and one vertical. The planar Lyapunov family undergoes a (quasi-periodic) pitchfork bifurcation giving rise to two families of quasi-periodic Halo orbits. Between them, there is a family of Lissajous quasiperiodic orbits, with three basic frequencies.