[1] Swiss Fed Inst Technol, Inst Geophys, Dept Earth Sci, Sonneggstr 5, Zurich, Switzerland
[2] Univ Zurich, Dept Phys, Winterthurerstr 190, Zurich, Switzerland
[3] European Space Agcy, European Space Astron Ctr, Madrid 28692, Spain
[4] Max Planck Inst Gravitat Phys, Albert Einstein Inst, Callinstr 38, D-30167 Hannover, Germany
[5] Leibniz Univ Hannover, Callinstr 38, D-30167 Hannover, Germany
[6] Univ Paris Diderot, APC, CNRS IN2P3, CEA Irfu,Obs Paris,Sorbonne Paris Cite, Paris, France
[7] Imperial Coll London, High Energy Phys Grp, Blackett Lab, Phys Dept, Prince Consort Rd, London SW7 2BW, England
[8] Univ Roma Tor Vergata, Dipartimento Fis, I-00133 Rome, Italy
[9] INFN, Sez Roma Tor Vergata, I-00133 Rome, Italy
[10] Univ Trento, Dept Ind Engn, Via Sommar 9, I-38123 Trento, Italy
[11] INFN, Trento Inst Fundamental Phys & Applicat, Rome, Italy
[12] Airbus Def & Space, Claude Dornier Str, D-88090 Immenstaad, Germany
[13] European Space Agcy, European Space Technol Ctr, Keplerlaan 1, NL-2200 AG Noordwijk, Netherlands
[14] Univ Trento, Dipartimento Fis, I-38123 Povo, Trento, Italy
[15] INFN, Trento Inst Fundamental Phys & Applicat, I-38123 Povo, Trento, Italy
[16] Univ Birmingham, Dept Phys & Astron, Birmingham, W Midlands, England
[17] INAF, Osservatorio Astron Capodimonte, I-80131 Naples, Italy
[18] INFN, Sez Napoli, I-80126 Naples, Italy
[19] Airbus Def & Space, Gunnels Wood Rd, Stevenage SG1 2AS, Herts, England
[20] Swiss Fed Inst Technol, Inst Geophys, Sonneggstr 5, CH-8092 Zurich, Switzerland
[21] Royal Observ, UK Astron Technol Ctr, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland
[22] Inst Ciencies Espai CSIC IEEC, Campus UAB,Carrer Can Magrans S-N, Cerdanyola Del Valles 08193, Spain
[23] Univ Urbino Carlo Bo, DISPEA, INFN, Via S Chiara 27, I-61029 Urbino, Italy
[24] European Space Agcy, European Space Operat Ctr, D-64293 Darmstadt, Germany
[25] Univ Zurich, Phys Inst, Winterthurerstr 190, CH-8057 Zurich, Switzerland
[26] Univ Glasgow, Sch Phys & Astron, SUPA, Inst Gravitat Res, Glasgow G12 8QQ, Lanark, Scotland
[27] Univ Politecn Cataluna, Dept Engn Elect, ES-08034 Barcelona, Spain
[28] Co Gen Spazio, CGS SpA, Via Gallarate 150, I-20151 Milan, Italy
[29] NASA, Goddard Space Flight Ctr, Gravitat Astrophys Lab, 8800 Greenbelt Rd, Greenbelt, MD 20771 USA
[30] Univ Firenze, Dipartimento Fis & Astron, I-50019 Florence, Italy
[31] INFN, Sez Firenze, I-50019 Florence, Italy