The effect of helium sedimentation on galaxy cluster masses and scaling relations G. E. Bulbul, N. Hasler, M. Bonamente, M. Joy, D. Marrone, A. Miller and T. Mroczkowski A&A, 533 (2011) A6 Published online: 11 August 2011 DOI: 10.1051/0004-6361/201016407