Presentation of the Iwasawa algebra of the first congruence kernel of a semi-simple, simply connected Chevalley group over Zp

It is a general principle that objects coming from semi-simple, simply connected (split) groups have explicit presentations like Serre's presentation of semi-simple Lie algebras and Steinberg's presentation of Chevalley groups. In this paper we give an explicit presentation (by generators and relations) of the Iwasawa algebra for the first congruence kernel of a semi-simple, simply connected Chevalley group over Zp, extending the proof given by Clozel for the group Γ1(SL2(Zp)), the first congruence kernel of SL2(Zp) for primes p>2.