its known as raful ya dayn

and yes its permissible

in sahih bukhari

hadhrat Abdullah ibn Umar (ra) said...

“I saw the Prophet's (sal-Allaahu 'alayhi was-Salam) opening takbeer in prayer; he raised his hands when he said “Allaahu akbar” until he held them parallel to his shoulders...” and in one report " & “When Allaah's Messenger (sal-Allaahu 'alayhi was-Salam) stood from the second rak‘ah, he said,‘Allaahu akbar' and raised his hands.”