I could not find references to rebirth in Vedic samhitas i.e.,  Rig Veda, Sama Veda, Yajur veda and Atharva veda. 

I would like to know what happens after death according to Vedic samhitas (Rig Veda, Sama Veda, Yajur veda or Atharva veda).

I heard that the Rig Veda describes how after death a man's eyes get merged in sun, breath in air, ashes in plants, but is this true? If not, then what exactly happens after death according to Vedic samhitas (Rig Veda, Sama veda, Yajur veda or Atharva veda)?