GAUGE Gr And Unification and Gravity Explorer Consortium

GAUGE Gr. And Unification and Gravity Explorer

Consortium K. Aplin 1, R. J. Bingham 1, M. Caldwell 1, A. M. Cruise 2, P. D’Arrigo 3, H. Dittus 4, J. Hough 5, P. Jetzer 6, N. Lockerbie 7, F. Loeffler 8, J. Mester 9, C. Pegrum 7, D. Shaul 10, T. J. Sumner 10, S. Theil 4, C. Torrie 5, P. Touboul 11, C. Trenkel 10, S. Vitale 12, W. Vodel 13, C. Wang 14, H. Ward 5 1 RAL, UK 2 University of Birmingham, UK 3 EADS Astrium, Stevenage, UK 4 ZARM, University of Bremen, DE 5 University of Glasgow, UK 6 ITP, University of Zurich, CH 7 University of Strathclyde, UK 8 PTB, Braunschweig, DE 9 University of Stanford, US 10 Imperial College London, UK 11 ONERA, Paris, FR 12 University of Trento, IT 13 University of Jena, UK 14 University of Aberdeen, UK

Background § ESA Cosmic Vision call for ideas (2004): approx. 50 ideas submitted, separately, in the area of “Fundamental Physics” § Informal feedback: in some cases significant overlap between proposed ideas → community should unite behind a few, strong proposals § Now: call for Cosmic Vision Mission Proposals in the near future…

Scientific Motivation GAUGE: Combine experiments that address key issues at the interface between gravity and quantum interactions Currently considered (NOT EXHAUSTIVE OR EXCLUSIVE): § Equivalence Principle tests § G/ISL measurements § Search for spin-dependent effects § Decoherence in Atom Interferometers § …?

Experiment concepts (to be selected from …) n EP measurement – Microscope, STEP – studied extensively within ESA/NASA n Microscope 1 part in 1015 n STEP 1 part in 1018

Experiment concepts - II n n G and 1/r 2 – STEP, ISLAND – better than 1 part in 105 (Possibility of LISAPF G measurement – 1 part in 104) (Quinn et al. 2001) Disagreement 2 x 10 -4

Experiment concepts - III n Spin-dependent effects – STEP, SSPIN

Experiment concepts - IV n Quantum decoherence - HYPER laser beam spacetime fluctuations atom beam laser beam detector fringe analyzer

Common technologies All potential experiments require n Drag-free environment n Precision displacement sensing of “proofmasses” n Magnetic (SQUIDS) n Electrostatic (Capacitive sensing) n Optical (Interferometry) n Cold atoms (Interferometry)

Heritage n n n Readout n Magnetic GP-B, STEP n Optical / Capacitive LISAPF, Microscope n Cold Atom HYPER + ground Spacecraft n Bus – LISAPF n Drag-free – LISAPF + LTP Space Experience within team n Astrium / Birmingham / Imperial / Onera / RAL / Stanford / Trento / ZARM

Mission Concept n n n Provide drag-free environment using LISAPF bus with LTP inertial sensor Modular experiment bays – different environments possible Launch into LEO sunsynchronous orbit with VEGA n Thermal Stability n Earth as Source

Some key dates § VEGA maiden flight: end 2007 § LISA PF success demonstrated: end 2010 … even allowing for delays, this should happen in time for mission in 2015 -2025

“Recipe” for success § Launcher, Spacecraft Bus and Drag-free Platform: existing technology § Payload: choose according to §Scientific Merit §Feasibility §Affordability § Inevitable Compromise

Plans § Submit Cosmic Vision Mission Proposal to ESA (deadline Summer 2007) § So far at UK level: well-received presentation to national Research Council (PPARC) § Several meetings planned in the near future: § Experimental concepts input and definition of Science Team § Experimental layout definition § Initiate industry-led accommodation study

Summary n n GAUGE is a mission at the interface of gravity and its unification with other interactions Mature technology Experienced team Fits into medium mission cost envelope → open invitation to collaborators!

… if interested please contact t. sumner@imperial. ac. uk