Q+A - Second bid to elect IAEA chief may deadlock again

By Mark Heinrich

VIENNA (Reuters) - The U.N. nuclear watchdog will try again to resolve a protracted leadership appointment on Thursday when it votes on a successor to Director-General Mohamed ElBaradei following a stalemate in March.

A Japanese diplomat has re-emerged as the frontrunner to take over the International Atomic Energy Agency. But another inconclusive outcome is likely this week, many diplomats say, raising the spectre of high-level disarray distracting the IAEA from a widening array of proliferation challenges, like Iran.

Here are questions and answers regarding the race to replace ElBaradei, a Nobel Peace Prize laureate who retires in November.

WHO IS RUNNING FOR ELBARADEI'S MANTLE?

* Yukiya Amano, Japan's veteran ambassador to the IAEA

* Abdul Samad Minty, the South African ambassador

* Luis Echavarri, Spanish head of the Organisation for Economic Cooperation and Development's nuclear energy branch