In 1917\/18 , two groups of scientists , Otto Hahn and Lise Meitner of Germany and Frederick Soddy and John Cranston of Great Britain , independently discovered another isotope of protactinium , 231Pa having much longer half-life of about 32,000 years .
They gave the new element the name Brevium ( Latin brevis , brief , short ) ; the name was changed to Protoactinium in 1918 when two groups of scientists ( Otto Hahn and Lise Meitner of Germany and Frederick Soddy and John Cranston of the UK ) independently discovered 231-Pa .