1. A Parasitic search for a muon EDM to 10 -xx e-cm using tracking Brendan Casey, Fermilab New (g-2) Collaboration Meeting 3/19/2011

2. B. Casey, 3/19/2011 2 A universe with matter Differences between matter and antimatter interactions allowed a small amount of matter to escape annihilation in the early universe –(4-6)x10 -11 baryon to photon ratio Observed CP violation in neutral meson mixing and decay only partially explains this –From CKM: < 6x10 -27 baryons/photon Huet, Sather PRD51 379 (1995) New effects needed. A small permanent electric dipole moment (EDM) of elementary particles is a good candidate. –Violates P and T sd

3. B. Casey, 3/19/2011 3 EDM expectations The large anomalous CPV in B s mixing reported at the Tevatron + minimal flavor violation predicts EDMs arearound the corner! –Gino Isidori, ICHEP 2010 plenary talk Need lepton and quark EDM searches to distinguish new weak interaction from a small QCD Need different leptons to determine if the new phase is universal Muon may be the only competitive place we can study EDMs outside the first generation Large B s CPV shrinks available parameter space Titanium neutron Mercury 10 -25 10 -30 Buras, Isidori, Paradisi arXiv:1007.5291 B s CPV

4. Muon EDM milestones B. Casey, 3/19/2011 4 10 -19 10 -20 10 -21 10 -22 10 -23 10 -24 Phys. Rev. D 80, 052008 (2009) |d |< 1.8 x 10 -19 e-cm @ 95% 10 -25 10 -26 10 -27 |d |< 10 -21 e-cm

5. Muon EDM milestones B. Casey, 3/19/2011 5 10 -19 10 -20 10 -21 10 -22 10 -23 10 -24 Phys. Rev. D 80, 052008 (2009) |d |< 1.8 x 10 -19 e-cm @ 95% 10 -25 10 -26 10 -27 |d |< 10 -21 e-cm Im Re a SM |d |~3 x 10 -22 e-cm

6. Muon EDM milestones B. Casey, 3/19/2011 6 10 -19 10 -20 10 -21 10 -22 10 -23 10 -24 Phys. Rev. D 80, 052008 (2009) |d |< 1.8 x 10 -19 e-cm @ 95% 10 -25 10 -26 10 -27 |d |< 10 -21 e-cm |d |~3 x 10 -22 e-cm |d | < 10 -24 e-cm: (m / m e ) 2 |d | < 10 -26 e-cm: (m / m e )

7. B. Casey, 3/19/2011 7 Experimental setup Muon sees E field pointing into the ring Muon EDM will tilt the precession plane Results in an up-down asymmetry in the positron decay angle, 90° out of phase M. Sossongs analysis note

8. B. Casey, 8/10/2010 8 Proposed update Previous measurement based on ~10 million reconstructed positron tracks Tracking detectors in front of all calorimeter stations could reconstruct ~10 11 tracks in the new experiment –Factor 100 reduction in limit Tracking volume Muon orbit Positron trajectory

9. B. Casey, 3/19/2011 9 Tracking design considerations asymmetry Convoluted with Michelle Spectrum Effective maximum asymmetry –Optimize design for positron momentum near 1.5 GeV Inherent angular spread in decay angle –Sets upstream material budget: keep multiple scattering below this. Occupancy throughout the fill –Sets how early we can take data Many more details outlined in Thursdays talk ~11 mrad RMS inherent decay angle in positron decay

10. Limit per POT B. Casey, 3/19/2011 10 We might have the statistics for 1 order of magnitude per 2 x 10 20 POT x 10 20 POT |d |

11. Tracking team B. Casey, 3/19/2011 11 Actively investigating cathode strip chambers, straws, and readout electronics options either inside the vacuum or using vacuum inserts Starting to investigate plastic scintillator and Silicon options as well Much more detail in Thursdays detector team talk Petersburg Nuclear Physics Institute

12. B. Casey, 3/19/2011 12 EDM conclusions Best current knowledge indicates EDMs will be seen in experiments this decade To understand what we see requires a measurement of the muon EDM We know how to improve by (at least) 2 orders of magnitude by adding tracking stations to the new (g-2) experiment This naturally progresses into a dedicated muon EDM experiment at Project X

13. B. Casey, 3/19/2011 13 Happy St. Patricks Day! Katie, Pono Dylan, Logan 3/17/2011