Central velocity of NH₃ (1, 1) (top) and (2, 2) (bottom) lines of the Guitar core in L1287 (color scale). The contours are the (1, 1) (top) and (2, 2) (bottom) integrated line emission. The velocity at the position of the emission peak is blueshifted ~ 0.3 km s⁻¹ with respect to the rest of the gas of the core. This blue spot at the emission peak of the core (the sound hole of the guitar) is the hallmark of infalling material (see text). The crosses are the YSOs identified in Fig. 3.