Status update of analysis note on "Hadronization studies via pi0 electroproduction" Taisiya Mineeva. Universidad Técnica Federico Santa María

Transcription

1 Status update of analysis note on "Hadronization studies via pi0 electroproduction" Taisiya Mineeva Universidad Técnica Federico Santa María CLAS collaboration meeting June

2 Status update on the analysis note T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 1/18

3 Hadronization T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction

4 Hadronization: vacuum Hadronization is the process by which energetic q and g evolve into hadrons Quark propagation: in hard hadronic processes, energetic partons can be temporarily liberated from hadrons; distribution of the color charge over an extended volume. Hadron formation: color charge is neutralized into color singlet hadrons. T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 2/18

5 Hadronization: in-medium Nuclear medium of variable size acts as a ruler that provides space-time information on hadronization process partonic multiple scattering medium-stimulated gluon emission additional prehadron interaction T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 3/18

6 Observables T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction

7 Kinematical variables of SIDIS k P t P h k q Q 2 = -q 2 four-momentum transferred by the electron; ν = E-E (lab) energy transferred by the electron; z = E h /ν fraction of initial quark energy carried by hadron; p T φ hadron momentum transverse to γ* direction; angle between leptonic and hadronic planes T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 4/18

8 Reaction of interest: SIDIS π 0 DIS regime: Q 2 > 1 (GeV/c) 2 and W > 2 GeV/c e D e π 0 X e A e π 0 X e (e ) 5 GeV e - beam D A π 0 γ1 (γ1) γ2 (γ2) X T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 5/18

9 Observables Transverse momentum broadening p 2 T =< p 2 T > A < p 2 T > D Connects to partonic phase in-medium scattering quark energy loss access to production time τp T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 6/18

10 Observables Hadronic multiplicity ratio R h A, Q 2, z, p T = N h (,Q 2,z,p T ) N e (,Q 2 ) DIS N h (,Q 2,z,p T ) N e (,Q 2 ) DIS A D Connects to hadronic phase hadron formation space-time mechanisms T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 7/18

11 Analysis note T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction

12 Analysis note Particle identification - electron ID - photon ID - π 0 reconstruction - binning Corrections - electron vertex - photon energy - e - and π 0 acceptance - radiative corrections Systematic studies > DC fiducial cuts > radiative corrections T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 8/18

13 Phase-space of the analysis was expanded pt2 = 0., 0.1, 0.25, 0.4, 0.55, 0.75, 0.9 z = 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 pt2 = 0., 0.1, 0.25, 0.4, 0.55, 0.75, 1.5 z = 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 1.0 Before Now Entire analysis is binned in 2 sets of 3D bins: (ν, z, pt 2 ) and (Q 2,ν, z) T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 9/18

14 Purity-based bin exclusion in (ν, z, pt 2 ) Exclude bins for which Purity < (1σ) 3 which amounts to Purity below 30% Purity = N rec gen N rec Purity in (Q 2,ν, z) set of bins exceeds 30% for all the bins T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 10/18

15 Multiplicity ratios in (ν, z, pt 2 ) Results are corrected for acceptance and radiative effects. Statistical uncertainties only. T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 11/18

16 Multiplicity ratios in (Q 2,ν, z) Results are corrected for acceptance and radiative effects. Statistical uncertainties only. T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 12/18

17 Status summary of systematic uncertainties Systematic uncertainties for C, Fe and Pb multiplicities in (Q 2, ν, z). Systematic uncertainties for C, Fe and Pb multiplicities in (ν, z, p 2 T ) bins. Systematic uncertainty C RMS (%) Fe RMS (%) Normalization type Target vertex cut Target leakage Sampling fraction cut Photon energy cuto EC time (beta) cut DC fiducial cuts Radiative corrections Bin-by-bin basis Background shape Signal shape Acceptance in finite bin width Total in (Q 2,, z) Pb RMS (%) Systematic uncertainty C RMS (%) Fe RMS (%) Normalization type Target vertex cut Target leakage Sampling fraction cut Photon energy cuto EC time (beta) cut DC fiducial cuts Radiative corrections Bin-by-bin basis Background shape Signal shape Acceptance in finite bin width Total in (, z, p 2 T ) Pb RMS (%) Work in progress: estimation of systematic uncertainties for the radiative corrections T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 13/18

18 UTFSM EG2 group at UTFSM Will Brooks (Director) Ahmed El Alaoui Hayk Hakobyan Taisiya Mineeva Sebastián Moran Jose Peña Antonio Radic Orlando Soto Theory support Boris Kopeliovich Benjamin Guiot T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 14/18

19 Independent cross checks of analysis: π 0 multiplicities Orlando Soto T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 15/18

20 Independent cross checks of analysis: π + multiplicities Multiplity Ratio Comparison for Zh, Acc Carbon Iron Lead Carbon (Rod) Iron (Rod) Lead (Rod) Z π + h Sebastián Moran T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 16/18

21 Independent cross checks of analysis: π + acceptance Discrepancy between the results (%), Acc, 4D and 5D * 100 % Bin(5D) - Bin(4D) Bin(4D) 2 Carbon Iron Lead Z π + h Sebastián Moran T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 17/18

22 Summary The phase space of the analysis was expanded up to z=1 and pt 2 =1.5 GeV 2 Multiplicity ratios in two sets of bins, acceptance corrections, radiative effects and systematic uncertainties were reevaluated correspondingly The systematic uncertainties on the multiplicity ratio, w/o uncertainty on radiative corrections, are 3-6 % depending on the bin set and target type What remains: systematics on radiative corrections We plan to submit answers to the review committee within the next several months T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 18/18

23 7 th International Conference on High Energy Physics in the LHC era Organizing Committee Sergey Kuleshov Diego Aristizábal Eugeny Levin William Brooks Sebastián Mendizábal Antonio Cárcamo Jonathan Miller Edson Carquín Taisiya Mineeva Oscar Castillo-Felisola Fedor Prokoshin Carlos Contreras Amir Rezaeian Gorazd Cvetic Maximiliano Rivera Claudio Dib Iván Schmidt Ahmed El Alaoui Marat Siddikov Hayk Hakobyan Pablo Ulloa Boris Kopeliovich Nicolás Viaux Sergey Kovalenko Alfonso Zerwekh Contact Phone: (56)(32) Universidad Técnica Federico Santa María Av. España 1680, Casilla 110-V, Valparaíso.

24 T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

25 Backup slides T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

26 Missing mass curves as a function of (pt2, z) T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

27 Radiative Corrections in (Q 2, ν, z ): SIDIS SIDIS contribution to RC factors for D, Fe and Fe/D ratio in set of (Q 2, ν, z )

28 Radiative Corrections in (Q 2, ν, z ): SIDIS + Exclusive SIDIS + Exclusive contribution to RC factors for D, Fe and Fe/D ratio in set of (Q 2, ν, z )

29 Radiative Corrections in (ν, z, pt 2 ): SIDIS

30 Radiative corrections C in (ν, z, pt 2 ): SIDIS + Exclusive

31 Multiplicity ratios T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

32 Multiplicity ratios in (ν, z, pt 2 ) Corrected for ACCEPTANCE ONLY P.S. low purity bins not excluded T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

33 Multiplicity ratios in (ν, z, pt 2 ) Corrected for ACCEPTANCE + Radiative corrections T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

34 Multiplicity ratios in (Q 2,ν, z) Corrected for ACCEPTANCE ONLY T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

35 Multiplicity ratios in (Q 2,ν, z) Corrected for ACCEPTANCE + Radiative Corrections T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17

36 T.Mineeva Status update of analysis note on "Hadronization studies via pi0 electroproduction 06/15/17