Hilchos Maasei Hakarbanos 3:11

The laying of hands on sacrificial animals is only done in the courtyard; if it was done outside the courtyard, it must be repeated inside. If the one bringing the offering stood outside the courtyard and he extended his hands inside, laying them on the animal’s head, it is valid so long as he pressed down with all his strength. Only one who is ritually clean may lay hands; if one who was ritually unclean did so, it is accepted.

Hilchos Maasei Hakarbanos 3:12

An animal must be slaughtered in the place where the hands were laid upon it, and it must be slaughtered immediately after the laying of the hands. If it was slaughtered elsewhere, or if there was a delay before slaughtering it, it is accepted. The laying of hands is a secondary component of the mitzvah. Therefore, if one didn’t lay hands on the offering, it nevertheless effects atonement, the laying of hands not being indispensable. However, it is considered as if the offering did not effect atonement (i.e., it is viewed as incomplete).