Charmless Baryonic DecaysB -> pph

Ping-Han ChuNational Taiwan University

2003.6.16Outline:1.Introduction2.Event Selection3.Physics Results4.Systematic Error5.Summary

Introdution

The current-produced() and transition() diagrams for B -> ppK

B

p

p

K

p

p

K

B

1.B+ -> ppK+

2.B+ -> pp+

3.B0 -> ppKs0

4.B+ -> ppK*+ ; (K*+ -> Ks0+ )

5.B0 -> ppK*0 ; (K*0 -> K+- )

Cited by Charmless three-body baryonic B decaysChun-Khiang Chua, Wei-Shu Hou, and Shang-Yuu Tsai, (PRD 66 054004)

…These modes are of interest not just because of possibly large rates, but also by accessibility in detection…

KEKB Accelerator

Asymmetric energy collision ofelectron = 8GeV, and positron = 3.5GeV

Ring circumference : 3kmRF frequency : 508MHz

Target Luminosity = 1034 /cm^2/secto produce more than 100 million B meson pairs in a year

KEKB Detector

Analyzed data

³ 4s reasonance sC10.58 Gev

85 million BB events (78fb-1) at the (4S) resonance recorded by the Belle before the summer 2002are used in this analysis.

Event and reconstruction

Mbc

dE

Mbc

dE

beamB

2B

2beambc

EEdE

PEM

(All In CM frame)

Event Selection

Track |dr| < 1 Track|dz| < 3

PID > 0.6; KID > 0.6; ID >0.6;

Vchisq > 0; GoodKs > 0

0.48< mass Ks <0.52 0.86< mass K* < 0.94

Signal Region:

Abs(dE)<0.05 5.27<Mb<5.29

Charm Veto possible reasonance2.85< Mpp <3.128 J/(3.07<mass<3.11,

c(2.97<mass<3.02)

3.315< Mpp <3.735 c0c1c2S

Lambda_c Veto2.259<MpKs<2.312 c

Continuum suppression

continuum background suppression

Event topoplogyModified Fox-Wolfram moments Fisher discriminants

Angular distributionB flight direction

e+

e-

b

B

B

B B

thr

jet-like qq events

spherical BB events

c)s,d,u, (q qqee

Angular distribution; B flight direction

e+ e-

b

B

B

B B

thr

a ar

aa a

P

)rd( d

)rPθ(rP)rd(

ˆ

ˆˆˆ

maxˆ

Modified Fox-Wolfram moments

r2so, r3so, r4so,r2oo, r3oo, r4oo

ji,ji

ji,ji,lji

sol pp

)(cosθPppR

Fisher discriminants

The use of multiple measurements in taxonomic problems.By R.A. Fisher. 1936. 10pp. Published in Annals Eugen.7:179-188,1936

NF7 LR

Fisher Parameters :costhr, spher, r2so,r4so,r2oo, r3oo, r4oo

Combined into a single Likelihood Ratio

PDF=NF7 fisher parameter ×cosb

qqs

s

PDFPDFPDF

LR

N

1iibcbsibcss )dE,(m)Pf(1)dE,(mPfL

Likelihood method for signal determination(2-D fit)

BS

S

NN

Nsig

Kpp

Significance = 15.3

11.210.5 -96.4 yields Fit

Kpp

J/C Signal

RegionSideband Region

Kpp

Mpp BF(10^-6)

1.875-2.0

2.0-2.2

2.2-2.4

2.4-2.6

2.6-2.8

2.8-3.4

3.4-4.0

4.0-4.6

4.6-5.0

Total

67.057.0

17.012.0

08.008.0

15.011.0

22.018.0

21.017.0

25.022.0

29.025.0

31.028.0

23.020.0

66.5

20.0

00.0

15.0

53.0

51.0

82.0

20.1

33.1

91.0

Significance = 6.7

8.17.7 -37.4 yields Fit

πpp

Signal Region

Sideband Region

πpp

Mpp BF(10^-6)

1.875-2.0

2.0-2.2

2.2-2.4

2.4-2.6

2.6-2.8

2.8-3.4

3.4-4.0

4.0-4.6

4.6-5.0

Total

73.062.0

54.045.0

21.021.0

16.011.0

04.004.0

12.012.0

21.017.0

19.016.0

23.020.0

15.013.0

06.3

00.1

15.0

15.0

00.0

05.0

46.0

39.0

57.0

29.0

πpp

Significance = 5.1

4.13.4 -11.3 yields Fit

0SKpp

J/C

Signal Region

Sideband Region

0SKpp

Mpp BF(10^-6)

1.875-2.0

2.0-2.2

2.2-2.4

2.4-2.6

2.6-2.8

2.8-3.4

3.4-4.0

4.0-4.6

4.6-5.0

Total

53.045.0

11.011.0

19.010.0

07.007.0

15.010.0

12.006.0

12.006.0

35.035.0

15.010.0

18.014.0

94.0

00.0

10.0

00.0

14.0

08.0

06.0

00.0

17.0

38.0

0SKpp

Significance = 6.0

4.64.0 -14.5 yields Fit

*Kpp

J/ Signal Region

Sideband Region

*Kpp

Mpp BF(10^-6)

1.875-2.0

2.0-2.2

2.2-2.4

2.4-2.6

2.6-2.8

2.8-3.4

3.4-4.0

4.0-4.6

Total

62.377.2

75.175.1

93.128.1

09.171.0

94.060.0

91.056.0

00.165.0

17.190.0

01.174.0

31.10

93.0

07.2

19.1

95.0

64.0

01.1

11.2

40.1

*Kpp

Significance = 3.14

5.734.93 -12.83 yields Fit

0*Kpp

Upper limit : 7.6*10-6

spectrum mass K and K -0S ππ

K*+

K*0

D0

Calibrator

3CC

3

100.40)(1.2)pp(η ; hpp h η B

100.10)(2.12)pp(J/ ; hpp hJ/ B

Β

Β

1.940.472.782.97Kpp

2.942.41Kpp

0.340.890.760.92 1.25Kpp

0.421.641.522.142.48Kpp

BelleηPDGJ/

0.300.23

0.570.54 -

1.120.93

0.210.20

0.250.25

0S

0.270.25

0.250.25

C)-6

10(

0

Compare with prevous result(exp7-exp13)

0.221.72 0.161.27 0.524.02 new

0.251.71 0.151.14 0.454.17 old

Kpp pp Kpp )10( 0-6

π

Note: Mpp<3.4GeV

Acp Check

Plus Minus Acp

50.50+-7.78 45.91+-7.55

-0.05+-0.11

21.57+-5.83 15.48+-5.57

-0.16+-0.22

Kppπpp

)()(

)()(

BNBN

BNBNACP

Upper limit of Glueball Search

0.90*10^-6 C.L.90%

Possible Hints and Search for Glueball Productin in Charmless Rare B DecaysChun-Khiang Chua, Wei-Shu Hou and Shang-Yuu Tsai (PLB544, 2002)

0.89*10^-6 C.L.90%

2.21 2.37

Systematic Error

13%13%16%-

12%12%11%TOTAL

1%1%1%1%1%)BN(B

NIL5%5%NILNIL0S

K

2%2%2%2%2% MC

4%4%11%-

4%5%4%fitting

6%6%6%6%6%LR

10%8%6%8%8%PID

4%5%4%3%3%tracking

0KppKpp0KppppKppmode\yuncertaint

π

CL) 90% atUL ,0(gg

2.780.572.97CL) 90% atUL 7.6,(Kpp

2.941.122.416.01.343.521.65 -2.77

1Kpp

0.920.251.255.10.110.530.45

0.94

0.220.16-6.70.370.730.62

3.06pp

0.110.05-2.120.252.4815.30.620.670.57

5.66Kpp

cpAPDGJ/ ψBr((B

))pp(J/ ψSig )6-10Br(

9.

0*

31.0*

0S

Kpp

π

)

Summary

Conclusion

1. spectrum can be compared with theorist's prediction.

2. Glueball search => giving upper limit.

3. The branching fraction of are different while

we don't see this kind phenomenon in the relative modes, e.g., J/K and J/Ks, because of different isospin components.

ppM

0Kpp and Kpp

Good Ks

Momentum <0.5 0.5~1.5 >1.5

Z distance <0.8 <1.8 <2.4

Fly length >0.08 >0.22

dr >0.05 >0.03 >0.02

d <0.3 <0.1 <0.03

Without GoodKs

With GoodKs

J/C Signal

RegionSideband Region

0*Kpp

Mpp BF(10^-6)

1.875-2.0

2.0-2.2

2.2-2.4

2.4-2.6

2.6-2.8

2.8-3.4

3.4-4.0

4.0-4.6

Total

20.193.0

64.047.0

58.047.0

17.017.0

34.025.0

31.020.0

35.025.0

48.038.0

30.030.0

12.3

70.0

79.0

00.0

41.0

23.0

25.0

75.0

00.0

0*Kpp