Systematic Error on S lepton and Gaugino Masses

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Systematic Error on S lepton and Gaugino Masses . OUTLINE Estimate systematic error on Slepton and Gauginos masses due to the knowledge of the luminosity spectrum: Reminder Guineapig distribution and Luminosity function F(√ s,Pn ) for nominal parameters - PowerPoint PPT Presentation

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Systematic Error on Slepton and Gaugino Masses 15 November 2012J-J.Blaising, LAPP/IN2P31OUTLINEEstimate systematic error on Slepton and Gauginos masses due to the knowledge of the luminosity spectrum: ReminderGuineapig distribution and Luminosity function F(s,Pn) for nominal parameters Luminosity functions F(s,Pi) for nominal parameters and for nm 0.5 and nm 5 Fit results and sensitivity to errors on the luminosity function parameters ConclusionReminder15 November 2012J-J.Blaising, LAPP/IN2P32-> ; two body kinematic decay => dN/dE is a uniform distribution with EL, EH bounds fixed by s, m and m.But s is not a delta function, box distorted by ISR and beamstrahlung.ISR is a QED process => well known.Beamstrahlung unknown, requiresmeasurement => potential source ofsystematic error

Reminder15 November 2012J-J.Blaising, LAPP/IN2P33A:S,Produced Bhabha events e e-> e e (-> Data set) with CLIC beam spectrum (Guineapig) as input, -> beam spectrum G(E1,E2) Modelel the beam spectrum with a function L(x1,x2) , x ,=E,/s.E, is the energy of the particles before ISR; taking into accountthe longitudinal boost and the correlation between the two particle energies -> Model with 19 parameters: F=L(x1,x2,pi) Fit F to Data to extract pi using the energy of the e e and their acollinearity -> dN/ds=L(Pn). Fit m and m using L(Pn), L(Pn, Pi+x), L(Pn,Pi-x), i=1,19 Lumi Fit Function15 November 2012J-J.Blaising, LAPP/IN2P34

F(s,Pi)=L(s,Pn) x ISR x (s) Pn=1,19 nominal values

Guineapig, F(s,Pn) distribution well known difference in peak region due to the non gaussian CLIC beam spread. Improvement requires a larger number of parameters. Fits with GP an F(s,Pn) =>Fit results with GP and F(s,Pn)15 November 2012J-J.Blaising, LAPP/IN2P35ProcessSlepton Mass with GP GeVSlepton MassNominal Pi GeVGauginoMass With GP GeVGaugino Mass Nominal Pi GeVe e-> 1005.5 5.01005.0 5.0

339.0 6.0339.1 6.0

e e-> e e

1011.81 1.81012.1 2.0339.8 2.6339.9 2.6 e e-> e e

1096.3 3.91095.7 3.9642.9 3.6642.3 3.6m is the statistical error, m(GP) m(F) < 1 GeVNon Gaussian CLIC beam spread is not an issue for Slepton mass determination.Lumi Fit Function15 November 2012J-J.Blaising, LAPP/IN2P36

Generate a set of 38 lumi functions19, F(s,Pn, Pj + 0.5 ) and 19 F(s,Pn, Pj 0.5 ) ; and another with19 F(s,Pn, Pj + 5 ) and 19 F(s,Pn, Pj 5 ) Compare nm, and 0.5 or nm, and 5 => plots F(s,Pn)=L(s,Pn) x ISR x (s)

Impact of variations of F(s,Pn)?F(s,Pn) and 0.5 15 November 2012J-J.Blaising, LAPP/IN2P37L(Pi) x ISR x (s) ; i=1,19

No very visibleDifference for nominal and 0.5 plots 15 November 2012J-J.Blaising, LAPP/IN2P38L(Pi) x ISR x (s) ; i=1,19

Difference for nominal and 5 Plots, P1, P5, P6, P7P9, P10, P11F(s,Pn) and 5 Fit Results with Pn and Pi+0.5/5 15 November 2012J-J.Blaising, LAPP/IN2P39Process PiError Slepton Mass With CorMSlepton MassNo CorMGauginoMass With CorM Gaugino Mass No CorMe e-> 0.5 1005.0 2.01005.0 2.3339.1 1.8339.1 1.7e e-> 51005.0 2.41005.0 2.6339.1 1.8339.1 2.6 e e-> e e0.5 1012.1 1.91012.1 2.0339.9 2.5339.9 2.5 e e-> e e51012.1 2.41012.1 2.8339.9 2.6339.9 3.2 e e-> e e 0.5 1095.7 1.51095.7 1.6642.3 1.8642.3 2.0 e e-> e e 51095.7 1.71095.7 2.6642.3 1.8642.3 2.7m is the systematic error due to the luminosity functionThe errors are not very sensitive to the variation of the error on the parameters, why ? => Analyze variations of F(s,Pi) Variation of for Pi + 0.5/5 and Pi 0.5/5 Variation of the peak content for Pi + 0.5/5 and Pi 0.5/5 Variation of vs Pi15 November 2012J-J.Blaising, LAPP/IN2P310For 5 errors, the variation on is between 0.1 and 0.6 GeVThe most sensitive parameters are P1, P5, P6, P7, P9, P10, P11The variations are symmetric ; P6, P7 are anti-correlatedP10, 11 as well

Variation of Peak Content vs Pi15 November 2012J-J.Blaising, LAPP/IN2P311For 5 errors, the variation of events in peak is about: 1.2% for P1, 0.5% for P5 and 0.4% for P9P1 and P5, P9 are anti-correlated

mass vs Pi15 November 2012J-J.Blaising, LAPP/IN2P312No striking difference between 0.5 and 5 errors

mass vs Pi15 November 2012J-J.Blaising, LAPP/IN2P313For 5 errors, dispersion slightly larger

Conclusion15 November 2012J-J.Blaising, LAPP/IN2P314To be conservative I would propose to take as systematic errors induced by the knowledge of the luminosity spectrum the ones based on 5 variation of the parameters

These results are slightly better than the ones in the CDR but consistent; correlations taken into account. Update the Slepton note using these values. ProcessSlepton Mass CDRGaugino MassCDRe e-> 1005.0 2.4 (0.2%) 0.2%339.1 1.8 (0.5%)0.6% e e-> e e1012.1 2.1 (0.2%) 0.2%339.9 2.5 (0.7%)1% e e-> e e 1095.7 1.7 (0.2%)0.2%642.3 1.8 (0.3%)0.4