▁is ▁the ▁mass ▁of ▁the ▁sphere , ▁r ▁is ▁the ▁radius , ▁and ▁r 0 ▁is ▁the ▁critical ▁mass ▁radius . ▁ ▁The ▁conclusion ▁drawn ▁was ▁that ▁a ▁few ▁kil og rams ▁would ▁expl ode ▁with ▁the ▁energy ▁of ▁thousands ▁of ▁tons ▁of ▁dynam ite . ▁ ▁In flu ence ▁ ▁The ▁memor and um ▁was ▁given ▁to ▁O li ph ant , ▁who ▁passed ▁it ▁on ▁to ▁T izard ▁ ▁in ▁his ▁capacity ▁as ▁the ▁chairman ▁of ▁the ▁Committee ▁for ▁the ▁Scient ific ▁Survey ▁of ▁Air ▁War fare ▁( CSS AW ). ▁He ▁in ▁turn ▁passed ▁it ▁to ▁Thom son , ▁the ▁chairman ▁of ▁the ▁committee ▁to ▁which ▁the ▁CSS AW ▁had ▁deleg ated ▁responsibility ▁for ▁u ran ium ▁research . ▁Thom son ' s ▁committee ▁was ▁about ▁to ▁dis band . ▁It ▁had ▁studied ▁nuclear ▁re actions ▁in ▁u ran ium , ▁and ▁the ▁use ▁of ▁graph ite ▁as ▁a ▁neut ron ▁moder ator ▁in ▁a ▁nuclear ▁re actor , ▁but ▁its ▁results ▁had ▁been ▁negative , ▁and ▁it ▁had ▁concluded ▁that ▁the ▁rate ▁of ▁capture ▁of ▁neut rons ▁by ▁the ▁graph ite ▁was ▁too ▁great ▁to ▁make ▁such ▁a ▁re actor ▁a ▁practical ▁proposition . ▁The ▁Fr isch – Pe ier ls ▁memor and um ▁caused ▁Thom son ▁to ▁re cons ider . ▁After ▁discuss ions ▁between ▁C ock cro ft , ▁O li ph ant ▁and ▁Thom son , ▁CSS AW ▁created ▁the ▁MA UD ▁Committee ▁to ▁investigate ▁further . ▁As ▁enemy ▁al iens , ▁Pe ier ls ▁and