Model ID 500 Ge V Taikan Suehara ICEPP

Model ID @ 500 Ge. V Taikan Suehara ICEPP, The Univ. of Tokyo Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 1

Topics • Threshold scan • Mass deviation in angle measurement Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 2

Threshold scan Generator info (bases output) s [fb] Sqrt(s) Raw (log plot) Normalized to 1 @ 500 Ge. V Threshold = 462 Ge. V (plot: 470 -) Beamstrahlung parameter: 500_nominal. root applied for all points (OK? ) Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 3

Threshold scan strategy • Use signal cross section at 3 points – Currently 470, 500, 530 (not optimized) • Signal efficiency & SM background are extracted from 500 Ge. V full-MC results – Background assumed to be same for all s – Loose cut vs. tight cut • Obtain c 2 for A(E-E 0)1. 5 and A(E-E 0)0. 5 – A and E 0 as free parameters (NDF=1) – 10000 reputation by Poisson at each point Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 4

Selection efficiency (revisited) • IH eff(LC): 27. 8%, eff(TC): 19. 9% BG (LC): 15. 254 fb • SUSY eff(LC): 26. 6%, eff(TC): 18. 8% BG (TC): 5. 474 fb • LHT eff(LC): 27. 9%, eff(TC): 20. 5% Note: eff. include hadronic BR (~46%) Loose Cut: 65 -95 Ge. V, Tight cut: 75 -85 Ge. V Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 5

Fit plot (LC) 50 each, s = 40 fb SUSY c 2(E 1. 5 fit) DH -1 fb LHT c 2(E 0. 5 fit) Sample s s Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 6

Fit plot (TC) 50 each, s = 40 fb SUSY c 2(E 1. 5 fit) DH -1 fb LHT c 2(E 0. 5 fit) Sample s s Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 7

Summary & todo (th. scan) • With 40 fb @ 500 Ge. V, 50 fb-1 x 3 statistics can separate SUSY from other 2 models – More powerful than angular distribution? • To. Do: – Quantitative measure – Lower cross section – s optimization Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 8

Mass deviation • Obtained mass resolution is finite – Affects the angular distribution – Mass error effect should be included or estimated for the angular measurement • Strategy – Full-MC • 4 deviated points in each model • 60000 events each (half statistics) – Generator level • 25 points in each (5 x 5 matrices) • 120000 events each Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 9

Data points • Full-MC – IH: 231. 18/44. 03, 231. 96/44. 03 231. 57/41. 80, 231. 57/46. 26 – SUSY: 231. 07/44. 03, 232. 07/44. 03 231. 57/41. 53, 231. 57/46. 53 – LHT: 231. 16/44. 03, 231. 98/44. 03 231. 57/42. 47, 231. 57/45. 59 • Generator level (matrix: 5 x 5 points) – IH: 231. 18/45/57/69/96, 41. 80/43. 46/46. 03/46. 60/46. 26 – SUSY: 231. 07/43/57/71/232. 07, 41. 53/45. 39/46. 03/46. 67/46. 53 – LHT: 231. 16/44/57/70/98, 42. 47/43. 53/46. 03/46. 53/45. 59 Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 10

IH (reco-no. BG) Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 11

SUSY Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 12

LHT Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 13

Chi-square for full-MC • Not yet… Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 14

Chi-square for generator files • 200 fb, 500 fb-1, no BG included • Cut efficiency 0. 27 applied (loose cut) • 25 IH templates: – Maximum c 2 in IH original signal: 318 – Minimum c 2 in SUSY: 2356, LHT: 2657 • 25 SUSY templates: – Maximum c 2 in SUSY original signal: 382 – Minimum c 2 in IH: 1639, LHT: 1431 • 25 LHT templates: – Maximum c 2 in LHT original signal: 390 – Minimum c 2 in IH: 1921, SUSY: 2166 Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 15

Summary & todo (mass shift) • Mass shift analysis ongoing, will soon be finished. • Generator study indicates mass shift gives no significant degradation for the angular analysis in 200 fb cross section. – 40 fb now checking • Need consistency check of full-MC and generator study Taikan Suehara, ILC-asia phys/opt meeting, 2010/06/04 page 16