1. Gordon Watts University of Washington – Seattle CPPM – Marseille Seminar Queen Mary – University of London May 27, 2015 3.5 m H Living Long at ATLAS

2. I used to be normal

3. What did we miss?

4. ?

7. What is Dark Matter? Baryon asymmetry? Why three families? Why those masses? Grand Unification?

8. The Higgs as a Probe

9. http://exotichiggs.physics.sunysb.edu SM + Scalar 2HDM + Scalar SM + Fermion SM + 2 Fermions SM + Vector MSSM NMSSM with exotic higgs decay to scalars NMSSM with exotic decays to fermions Little Higgs Hidden Valleys 1312.4992v4

10. The Standard Model The Extended Model Communication Mechanism

11. Energy Us, daily life LEP Tevatron LHC Run 1 LHC (Run 2)

12. Energy LHC (Run 2) SM Physics of the Hidden Valley Tunneling/Mixing Standard Model Particles Mixing

13. Energy What it decays to, how many of them will you expect, kinematics, etc. How long it lives

14. The mixing means the end result will be Standard Model Particles Couples to heavy fermions “lepton-jets” – jets of leptons

15. Higgs (like) communicator Displaced jets Very little else nearby

18. Distance from the Interaction Point [Detector] Decay Product [LJ or Hadronic Jets]

19. Distance from the Interaction Point [Detector] Decay Product [LJ or Hadronic Jets] Prompt Displaced Vertex in a Tracker Jet Appearing in the Calorimeter Jet Appearing in the Muon Spectrometer

20. Distance from the Interaction Point [Detector] Decay Product [LJ or Hadronic Jets] Prompt Displaced Vertex in a Tracker Jet Appearing in the Calorimeter Jet Appearing in the Muon Spectrometer

21. Decays Inner Detector Calorimeters Muon Detectors

23. Decays in the Inner Detector

24. Re-Tracking # hits in Silicon 62 Vertexing

27. Decays in the Calorimeter 1.Look for the “appearance” of energy the Calorimeter 2.Little or no activity in the tracker

29. “CalRatio”

31. Decays in the Muon Spectrometer 1.Look for a vertex in the ATLAS Muon Spectrometer 2.Lack of activity in the Tracker 3.Lack of activity in the Calorimeters

32. Toroidal Magnetic Field

33. 170 mm

36. Inner Detector: CalRatio: MS Vertexing: 0 – 0.3 m 1.9 – 3.6 m 3.8 – 7.5 m Sensitivity

37. Associated Production The events must be written to tape… 1 e.g. WH production Signature Driven Trigger 2 ATLAS has 3 signature driven triggers running since the start of 2011: Trackless Jet Trigger CalRatio trigger Muon RoI Cluster Trigger All triggers must be below 1 Hz!

38. Large number of muon drift tube hits (MDTs) Causes Muon RoI Level 1 Trigger Hits

39. Beam Halo Muon (Calorimeter shown) “Line of Fire”

40. Acceptance Small Backgrounds A single displaced vertex Two displaced vertices

41. Displaced TriggerTopology Yes-2 ID YesMSID + MS YesMS2 MS -CalRatio2 CalRatio Combined

42. (QCD) 2-CalRatio (Trigger Jet) (QCD) MS (Punch through, combinatoric)

43. Total expected background is just combining these fake rates Works except for 2-CalRatio! Assuming each vertex fake rate is independent

44. The full CalRatio selection: quark gluon quark gluon Both cuts are correlated with quark/gluon jets QCD production correlates the jet types!

45. Displaced Trigger TopologyExpectedObserved Yes-2 ID0 YesMSID + MS0 YesMS2 MS2 -CalRatio2 CalRatio24

48. MS-ID All Channels2-CalRatio

49. MS-ID All Channels2-CalRatio

51. Conclusions ATLAS has completed a fairly comprehensive set of searches for long lived particles decaying to jets! SUSY searches not discussed here! Substantial parts of phase space for exotic Higgs decays have been ruled out As well as heavier mass scalar decays A lot of room for improvement in Run 2 Combined analyses, better results for theorists Include other objects besides displaced vertices 13 TeV collision from other night!

52. Thanks! Daniel Blackburn Students Orin Harris Rachel Rosten Heather Russell Senior People Andrea Coccaro Henry Lubatti Monica Verducci And to ATLASAnd the LHC!