To whom does the Turkish form of the Persian title Shahzade refer?

Şehzade is the Turkish form of the Persian title Shahzade, and refers to the male descendants of an Ottoman sovereign in the male line. This title is equivalent to "prince of the blood imperial" in English. In formal address, this title is used with title sultan before a given name, reflecting the Ottoman conception of sovereign power as a family prerogative. Only a şehzade had the right to succeed to the throne. Before the reign of Mehmed II (1444-1446 and 1451-1481), sons of sultans used the title Çelebi after their name.