1. Taking a Razor to Dark Matter Parameter Space (at the LHC) Chiu-Tien Yu (UW-Madison/Fermilab) with Paddy Fox, Roni Harnik, and Reinard Primulando arXiv: 1203.1662 May 8, 2012 Phenomenology 2012 Symposium

2. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 There is a strong case for the existence of dark matter 1

3. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Looking for DM DM SM collider indirect direct 2

4. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Direct Detection arXiv:1104.2549 impressive work, still has a lot of unresolved issues (PRL, 106:021303, 2011) arXiv:1104.2549 3

5. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Direct Detection arXiv:1104.2549 impressive work, still has a lot of unresolved issues backgrounds, calibration, local DM density,... (PRL, 106:021303, 2011) velocity suppression recoil energy threshold 3

6. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 DM SM collider indirect DM SM indirect direct 4

7. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 No low energy threshold at colliders does fine with spin-dependence complementary to direct detection experiments 5

8. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 DM SM Dark Matter at Colliders 6

9. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 something DM SM Dark Matter at Colliders 6

10. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 something DM SM Dark Matter at Colliders We can use monojet (or monophoton) searches to place limits on the direct detection plane. 6

11. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 3 simple steps to finding DM Assume that an effective field theory is valid at the collider -- consider contact operators Find the collider limit on the scale Lambda by looking for an excess of events Translate the Lambda bound into a direct detection cross-section 7

12. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Effective Field Theory Spin-independent, vector exchange Spin-dependent, axial-vector exchange Spin-independent, gluon operator 8

13. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Effective Field Theory Spin-independent, vector exchange Spin-dependent, axial-vector exchange Spin-independent, gluon operator Collider searches can tell you something about these. 8

14. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 dominant backgrounddominant signal initial-state 9

15. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 dominant backgrounddominant signal initial-state Z preferentially emitted with low pT, so jet(s) are as well. Jet(s) distributed isotropically Exploit this difference in kinematics * 9

16. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 10

17. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Some great monojet/photon theory papers... Fermilab clan: P. Fox, J. Kopp, R. Harnik, Y. Tsai Missing Energy Signatures of Dark Matter at the LHCarXiv:1109.4398LEP Shines Light on Dark MatterPhys. Rev. D84, 014028 (2011).Irvine contingent: J. Goodman, M. Ibe, A. Rajaraman, W. Shepherd,T. M. P. Tait, A. M. Wijangco, and H. -B. YuLHC Bounds on Interactions of Dark MatterarXiv:1108.1196Constraints on Dark Matter from CollidersPhys. Rev. D82, 116010 (2010)Constraints on Light Majorana dark Matter from CollidersPhys. Lett. B695, 185-188 (2011) 11

18. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012...that caught the attention of the experimental community. 12

19. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 something DM SM Dark Matter at Colliders Monojets do ok, but can we do better? 13

20. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 something DM SM Dark Matter at Colliders jets are cheap at the LHC ($) 13

21. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 somethings DM SM Dark Matter at Colliders jets are cheap at the LHC ($) 13

22. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 DM SM Dark Matter at Colliders jets are cheap at the LHC ($)...and give you more handles on the data. Plus, complementary to monojets. ($$$) 13 somethings

23. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Enter, the Razor CMS analysis for SUSY using 2D distribution of two kinematic variables. Takes multijet events and puts them into a di-“megajet” topology -- keep more events. Variables follow simple exponential distributions -- data-driven analysis. 14

24. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Enter, the Razor } estimate the scale of the event } ratio of MET to visible low R jet 1 jet 2 high R jet 1 jet 2 15

25. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Enter, the Razor Z+jets100 GeV DM 16

26. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Enter, the Razor Z+jets100 GeV DM signal region 16

27. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 800 pb -1 LHC7 Razor results 17

28. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 800 pb -1 LHC7 Razor results best limits at low mass best limits everywhere 17

29. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Conclusion Collider searches for DM give complementary (and competitive) bounds to direct detection searches. Current monojet/monophoton analyses from the Tevatron and LHC give the best limits for light DM and for spin- dependent DM. Inclusive jet + MET searches such as Razor will provide even more discriminating power. 18

30. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 Conclusion Collider searches for DM give complementary (and competitive) bounds to direct detection searches. Current monojet/monophoton analyses from the Tevatron and LHC give the best limits for light DM and for spin- dependent DM. Inclusive jet + MET searches such as Razor will provide even more discriminating power. Watch for this! 18

31. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 backups

32. Chiu-Tien Yu (UW-Madison/Fermilab) Pheno2012 May 8, 2012 light mediators 19