Measurements of the Masses, Mixing, and Lifetimes, of B Hadrons at the Tevatron

Transcription

1 Meaurement of the Mae, Mixing, and Lifetime, of Hadron at the Tevatron Mike Strau The Univerity of Oklahoma for the CDF and DØ Collaboration 5 th Rencontre du Vietnam Hanoi, Vietnam Augut 5-11, 2004

2 Outline Phyic at the Tevatron Reonance 0 ocillation Lifetime Excluive Decay Lifetime Ratio and Difference 2

3 Tevatron Luminoity ~0.3 fb 1 delivered thi year Detector collect data at typically 85% efficiency Thee analye ue pb 1 About 150 pb 1 of data ha been recorded but not yet analyzed 3

4 Phyic at the Tevatron Large production cro ection All Hadron produced (et and Λ b ) Larger inelatic cro ection (S/ 10-3 ) Specialized Trigger: Single lepton trigger Dilepton trigger (e.g. J/ ψ µ + µ ) L1 Track trigger L2 diplaced track trigger for CDF σ(pp bb) 150 µb at 2 TeV σ(e + e bb) 7 nb at Z 0 σ(e + e bb) 1 nb at ϒ(4S) 4

5 Detector Silicon vertex tracker, Axial olenoid, Central tracking, High rate trigger/daq, Calorimeter, Muon ytem CDF DØ L2 trigger on diplaced vertexe Low p particle ID (TOF and de/dx) Excellent ma reolution Excellent muon ID; η < 2 Tracking acceptance η < 2-3 L3 trigger on impact parameter 5

6 X(3872) CDF and DØ have confirmed elle dicovery of the X(3872) 730 ± 90 candidate ~12 σ effect M X = ± 0.7 (tat) ± 0.4 (y) MeV/c 2 elle: M X = ± 0.6 (tat) ± 0.5 (y) M = ± 3.1(tat) ± 3.0 (y) MeV/c 2 M +M(J/ψ) = ±4.3 MeV/c 2 6

7 X(3872) ψ(2s) comparion I the X charmonium, or maybe an exotic meon molecule? y <1 coθ π <0.4 dl<0.1 coθ µ <0.4 p T >15 GeV/c Io=1 CDF Long-lifetime fraction: ψ(2s): 28.3±1.0(tat) ±0.7(yt) X(3872): 16.1±4.9(tat) ±2.0(yt) DØ multi-parameter comparion 7

8 Firt Obervation of S φφ R( φφ ) = 1.4 ± 0.6(tat) ± 0.2(yt) ± 0.5(R)

9 Search for 0 (,d) µ+ µ SM R( 0 µ + µ - ) (3.4±0.5) 10-9 ; R( d0 µ + µ - ) (1.5±0.9) Expected G: 1.05 ± 0.30 R( 0 µ + µ ): < at 95% CL (CDF) Expected G: 3.7 ± 1.1 event R( 0 µ + µ ): < at 95% CL (DØ) R( d 0 µ + µ ): < at 95% CL 9

10 Obervation of ** Spectrocopy: (J p = 0 ) *(J p = 1 ) decay to γ (100%) M = M( * ) M() = 46 MeV/c 2 The ** conit of four eparate tate 2 narrow tate 1 (1 + ) and 2 * (2 + ), decay via D-wave; 2 wide tate 0 *(0 + ) and 1 ' (1 + ), decay via S-wave; None of thee individual tate are well etablihed Decay channel ued: d ** ± π + ; ** + d π + ; ** *π π (γ) ± J/ψ K ± ; d J/ψ K *0 ; d J/ψ K 0 10

11 Ditinct Narrow ** State 350 pb 1 Sum of 3 decay mode The firt direct meaurement of mae and plitting between 2 * and 1 M( * ) = M() + 46 MeV (γ) 1 π (γ) 2 * π (γ) 2 * π M( 1 ) = 5724 ± 4 ± 7 MeV /c 2 M( 2* ) M( 1 ) = 23.6 ± 7.7 ± 3.9 MeV/c 2 11

12 d Mixing In SM d mixing i explained by box diagram Contrain V td CKM matrix element Mixing frequency m d ha been meaured with high preciion at e + e factorie (0.502 ± p -1 ) m d meaurement at Hadron Collider Confirm initial tate flavor tagging for later ue in and m meaurement 12

13 Ocillation Variable Oppoite ide b 1/3 Q<0 b 0 π b π + Same ide b K (CDF) K + b (CDF) 13

14 0 Mixing with SS Tag A = (N RS N WS )/(N RS +N WS ) N RS :N( 0 π + ) N WS :N( 0 π ) m d = ± 0.052(tat) ± 0.030(c) ± 0.012(yt) p -1 14

15 0 Mixing with SS Tag µ D*X, D* D 0 π Viible Proper Decay Length: x M = L xy M c /p T µd Preliminary Tagging purity: 55.8 ± 0.7 ± 0.8 % m d = ± 0.066(tat) ± 0.044(yt) p -1 15

16 0 Mixing with OS µ Tag Preliminary Decay Mode: µ D*X, D* D 0 π Tagging: muon p T > 2.5 GeV/c co φ(µ,) < 0.5 Tagging efficiency: 4.8 ± 0.2 % Tagging purity: 73.0 ± 2.1 % Fit procedure inned χ 2 fit m d = ± 0.055(tat) ± 0.049(yt) p -1 Combined reult uing three tagging method will be releaed oon 16

17 Hadron Lifetime Naive quark pectator model: a 1 3 decay proce common to all hadron. (NLO) QCD Heavy Quark Expanion predict deviation in rough agreement with data Experimental and theoretical uncertaintie are comparable Lifetime difference probe the HQE to 3 rd order in Λ QCD / m b Goal: meaure the ratio accurately 17

18 Hadron Lifetime Ratio 18

19 Λ b Lifetime DØ DØ Preliminary New Meaurement from DØ Λ b J/ψ Λ 0 DØ τ(λ b ) = ±0.043 p τ(λ b )/τ( d0 ) = ± CDF Preliminary from 2003: τ(λ b ) = 1.25 ±0.26 ±0.10 p 19

20 Lifetime uing J/ψ φ CDF 250 pb -1 Preliminary DØ Improvement ince 2003: Selection minimize tat yt 12 parameter maximum likelihood fit 240 pb -1 Preliminary DØ analyi i imilar to thi CDF improved analyi 20

21 Lifetime uing J/ψ φ CDF DØ Preliminary Preliminary 250 pb -1 τ( ) = 1.369± p τ( ) = ±0.020 p Ue one exponential decay in the fit 21

22 d Lifetime Uing d J/ψ K * 0 CDF DØ Preliminary 250 pb -1 τ( 0 ) = 1.539±0.051±0.008 p τ( )/τ( 0 ) = 0.890± τ( d 0 ) = ±0.023 p τ( )/τ( ) = ±

23 + Lifetime Uing J/ψ K + τ( + ) = 1.662±0.033±0.008 p τ( + )/τ( 0 ) = 1.080±0.042 Mot ytematic uncertaintie cancel in the ratio 23

24 Lifetime Ratio τ ( + )/τ ( 0 ) Novel Analyi Technique uing µd c(*) X Directly meaure ratio intead of individual lifetime Split D 0 Kπ ample: D* + (with low π + ) mainly from 0 D 0 mainly from + 12% + 2% S PV 0 D *- µd0 µ + K + π D 0 - π - ν D* + D 0 86% 0 16% 0 2% S 82% + 24

25 Lifetime Ratio τ ( + )/τ ( 0 ) Meaure N(µD* + )/N(µD 0 ) in bin of VPDL In both cae fit D 0 ignal to extract N Ue low pion only to ditinguih 0 from + (not in vertexing, K- factor etc., to avoid lifetime bia) τ( + )/τ( 0 ) = ± 0.021(tat) ± 0.022(yt) 25

26 26 Decay Angular Amplitude Ue J/ψ φ; Ue d J/ψ K* 0 Allow meaurement of many parameter including polarization amplitude and Γ = 1/τ L 1/τ H ( ) ( ) L H q p q p = = + = + = CP odd CP even ( ) ( ) L H L H = + =

27 Tranverity Angle The J/ψ ret frame KK define (x,y) plane K + (K) define +y direction Θ, Φ: polar & azimuthal angle of µ + Ψ: helicity angle of φ(k*) Extract polarization amplitude: A 0 : Longitudinal A, A : Tranvere 27

28 Angular Projection and fit for Decay Angular Ditribution: 4 d P r = dρ dt 6 i= 1 A i g ρ =(Θ, Φ, Ψ) i () t f ( ρ ) i r 28

29 Ma and Lifetime Projection Uncontrained fit τ L = 1.05 ± 0.02 p τ H = ± 0.03 p Γ = 0.47 ± 0.01 p Γ Γ = 0.65 ± Uing SM and contrained fit: +65 m = 125 p

30 and d Amplitude DØ reult coming oon For 0 d A 0 = ± ± A = (0.473 ± ± 0.006) ei(2.86 ± 0.22 ± 0.04) A = (0.482 ± ± 0.014) ei(0.15 ± 0.15 ± 0.04) For 0 A 0 = ± ± A = (0.510 ± ± 0.013) e A = ± ± i(1.94 ± 0.36 ± 0.03) 30

31 Concluion DØ and CDF are meauring many propertie of hadron that nicely complement thoe meaured at factorie We expect 500 pb -1 by the end of the year More exciting reult are expected even in the next few week 31