arXiv:1202.4112v1 [cond-mat.supr-con] 18 Feb 2012 Magnetically driven superconductivity in CeCu 2 Si 2 O. Stockert, 1, ∗ J. Arndt, 1 E. Faulhaber, 2, 3 C. Geibel, 1 H. S. Jeevan, 1, 4 S. Kirchner, 1, 5 M. Loewenhaupt, 2 K. Schmalzl, 6 W. Schmidt, 6 Q. Si, 7 and F. Steglich 1 1 Max-Planck-Institut f¨ ur Chemische Physik fester Stoffe, 01187 Dresden, Germany 2 Institut f¨ ur Festk¨ orperphysik, Technische Universit¨ at Dresden, 01062 Dresden, Germany 3 Gemeinsame Forschergruppe Helmholtz-Zentrum Berlin - TU Dresden, 85747 Garching, Germany 4 I. Physikalisches Institut, Universit¨ at G¨ ottingen, 37077 G¨ ottingen, Germany 5 Max-Planck-Institut f¨ ur Physik komplexer Systeme, 01187 Dresden, Germany 6 J¨ ulich Centre for Neutron Science at Institut Laue-Langevin, 38042 Grenoble, France 7 Department of Physics and Astronomy, Rice University, Houston, Texas, 77005, USA (Dated: February 21, 2012) Abstract PACS numbers: * Electronic address: stockert@cpfs.mpg.de 1