1. Daejung Kong and Kihyeon Cho* (High Energy Physics Team, KISTI)
France-Korea CDF Workshop
Paris, France
June 29-July 1, 2009
Bs KISTI
Daejung Kong and Kihyeon Cho*
(High Energy Physics Team, KISTI)
* Corresponding Author

2. Content High Energy Physics Team at KISTI Motivation
Bs physics that we have done
Bs physics plan at KISTI
Summary

3. e-Science paradigm Hardness e-Science Effects -Today e-Science
Theory
Exp.
Comp.
e-Science
-Today
e-Science
Data Centric Science
unify theory, experiment, and simulation
Computational
Science
-Last few decades
Computational Science
simulation of complex phenomena 이론 실험
Comp.
Theoretical
Science
-Last few hundred years
-Theoretical Science
-Newton’s Laws, Maxwell’s Equations …
Experimental
Science
HPC and Information Management are Key Technologies to support e-Science Revolution
-Thousand Years ago
-Experimental Science
- description of natural phenomena
Tony Hey (MS)
Effects

4. High Energy Physics Team @ KISTI
After constructing e-Science paradigm
To enable discovery in B physics
e-Science
Theory
Computing
Experiment

5. Man Power @HEP team, KISTI
Theory
Lepton Collider
(Belle II)
Hardon Collider
(CDF)
Soo-hyeon Nam
Yongseok Oh
B Physics
Junghyun Kim
Kihyeon Cho
Daejung Kong
Ilsung Cho

7. Theory @ KISTI by S.-h Nam
Semi-leptonic
Semi-leptonic b-> c l mu transition
Semi-leptonic b-> u l mu transition
Leptonic B-> tau nu
Non-leptonic
b -> s gamma
B Bbar Mixing
Sin2beta_s (S.-h.Nam, PRD (2003) )
Polarization Fraction

8. B physics that we have done - The Tevatron is a Full Service of B Factory
Lightest B Mesons
Heavier B Mesons
Baryons: bu bd bs bc
bud B+ B0 Bs Bc
Antimesons:
Antibaryons:
페르미연구소에 있는 테바트론은 full service of B factory라고 부릅니다.
BaBar나 Belle에서는 light B 메존만 만들 수 있습니다.
페르미연구소의 Tevatron은 Heavy B도 만들어 낼 수 있으므로 Full service B factory라고 불리어집니다.
본인은 BaBar 및 Belle에서 할 수 없는 Bs와 같은 무거운 B 메존에 관한 연구를 하고 있습니다. bu bd bs bc
b u d B- B0 Bs Bc
Upsilon:
BaBar and Belle energy is too low to make these modes! bb

9. Observation of Bs -> Ψ(2S)Φ
, one Candidate event reported at ALEPH(1993)
Nobody measured ratio of Bs Charmonium final state till 2006.
Bs -> Ψ(2S) Φ is similar to Bs -> J/Ψ Φ for DG/G measurement
[PDG ‘04]
[Babar‘02] ??
350 pb-1
D. Kong, K. Cho, et, al. PRL 96, (2006)
PDG2007
 Now, 5fb-1 Data

10. December 4, 2018 10

11. ~ 6 times yield increased
Reconstruction of Bs → ψ(2S) φ
350 pb-1
2 fb-1
1 fb-1
121.9±13.6 events
~ 6 times yield increased
~ 3 times yield increased

12. B Physics Plan @ KISTI Search for Search for Study for
Production Mechanism

13. Di-muon triggered DataSet @ CDF
xpmm data : xpmm0d xpmm0e xpmm0h xpmm0i xpmm0j xpmm0k xpmm0m
File Count :
Ave. Size(GB):
File Size(TB) :
Event Count :
==============================================================================================
Total File Size : ~ 12 TB

14. Search for Bs  J/Ψπ+ π- Φ
Could be a good method to separate production mechanism
Internal pop up vs. Higher resonance state ?
X(3872) or ψ(2s) -> J/Ψ π+π- ?
Br(B0  J/ π+ π- K*0) / Br(B0  (2s)(J/ π+ π- ) K*0 )
Br(B+  J/ π+ π- K+) / Br(B+ (2s)(J/ π+ π- ) K+ )
Br(BS  J/ π+ π-  ) / Br(BS  (2s)(J/ π+ π- )  )
B=B+ , K=K+
B=B0, K=K*0
B=BS, K=φ
B→ J/ψ K
(1.007±0.035)*10-3
(1.33±0.06)*10-3
(1.3±0.4)*10-3
B→ J/ψ Kπ+π-
(1.07±0.19)*10-3
(6.6±2.2)*10-4
B→ψ(2s)K
(6.48±0.35)*10-4
(7.2±0.8)*10-4
(6.8±3.0)*10-4
B→ψ(2s)Kπ+π-
(1.9±1.2)*10-3

15. Event Selection of BsJ/Ψπ+π-Φ ≈ BsJ/ΨΦ
Event Selection, Bs  J/Ψπ+ π-Φ
Bs  J/ΨΦπ+π-
Bs  Ψ(2S)Φπ+π-
Event Selection of BsJ/Ψπ+π-Φ ≈ BsJ/ΨΦ

16. Expected yield of Bs  J/Ψπ+ π-Φ
Expectation ~ 5fb-1
Expectation ~ 5fb-1
Similar yield ~ Bs  J/ΨΦπ+π-
Similar yield ~ Bs  Ψ(2S)Φπ+π-

17. Search for Bs  J/Ψ Ks Nobody measured ratio of Bs  J/psi Ks
Color & Cabibbo Suppressed Mode
Extracting CKM γ angle (Ref : Eur. Phys. J. C10, (1999))
By-product -> Penguin effects from Bd  J/psi Ks

18. Search for Bs -> J/ΨKs, psi(2S)Ks
Control Sample is Bs -> J/psi phi.
Br(Bs -> J/psi Ks) / Br(Bs -> J/psi pi) = 0.05 (?)
SM or New Physics?

19. Event Selection Bs  J/ΨKs Event Selection of Bs  J/ΨKs ≈ B0  J/ΨKs

20. Search for Bs  J/ΨKs @ CDF II
Measured Br(B0  J/Ψ Ks) = 4.45*10-4
Theory exp. Br(Bs  J/Ψ Ks) ~ 2.0*10-5
Yield (B0  J/ΨKs) ~ (0.8fb-1) : measur
Yield (B0  J/ΨKs) ~ (5.0fb-1) : expect
Expected Yield (Bs  J/Ψ Ks) @ 5.0fb-1
~ * 0.3(fs/fb) * 2/4.45*10-1
~ 200
* B0 contamination, BG reduction

21. J/Ψπ+ π- Production Mechanism
Could be a good method to separate production mechanism
By study of soft π+π-
Singlet production or octet production?
M(J/psi pi+pi-) distributions after large PT of J/psi cut
Flat => Octet
Jet => Singlet

22. J/Ψπ+ π- Production Mechanism
Working together theory group at Korea University. (Prof. J.Lee)
J/psi pi pi is same final state of Bs-> J/psi pi pi
Same stream and ntuple

23. Summary
High Energy Physics KISTI is working on e-Science paradigm of computing-experiment-theory in B physics
We are making synergy on B physics for both theory and experiment and both hadron collider experiment and lepton collider experiment.

24. Summary (cont’d)
Common searches in Bs physics between KISTI and France
Same Physics Stream: dimuon
Same Control Sample Bs -> J/psi phi
Bs sector is crucial to search new physics beyond Standard Model.

25. Thank you.

26. Bs -> J/Ψ Φ π+π- 26 J/ π π, K
Could be a good method to separate production mechanism?
Internal pop up v.s. Higher resonance state ?
X(3872) or ψ(2s) -> J/Ψ π+π- ?
Br(B0  J/ π+ π- K*0) / Br(B0  (2s)(J/ π+ π- ) K*0 )
Br(B+  J/ π+ π- K+) / Br(B+ (2s)(J/ π+ π- ) K+ )
Br(BS  J/ π+ π-  ) / Br(BS  (2s)(J/ π+ π- )  )
J/
Charmonium J/ π+ π-
K*0, K+, π
K*0, K+, 
π, K
B=B+ , K=K+
B=B0, K=K*0
B=BS, K=φ
B→ J/ψ K
(1.008±0.035)*10-3
(1.33±0.06)*10-3
(9.2±3.3)*10-4
B→ ψ(2s)K
(6.48 ± 0.35) *10-4
(7.2 ±0.8) *10-4
(4.8±1.4)*10-4
B→ J/ψ K π+π-
(1.07 ± 0.19) *10-3
(6.6 ±2.2) *10-4
B→ ψ(2s)K π+π-
(1.9 ± 1.2) *10-3 26 26

27. E-Science
Theory
Computing
Experiment

28. Bs Physics (France & KISTI group]
After measuring with an unprecedented precision the oscillation frequency
between Bs and anti-Bs states,
we are measuring the lifetime difference and the CPV phase in order to see
if any deviation with the SM expectation.
Very high precision measurements => a way to look for New Physics.
Important breakthrough and even possible discovery with the full Luminosity.

29. Bs physics common searches
Physics stream
B physics with different data based on   and 2 track triggers mainly for Bs Mixing (CDF discovery in 2006) pursuing since two years on CP violation studies in the Bs sector
Same physics streams
B → J/ψ Φ: CP violation related studies
CP even and odd measurement: sin2βs (France)
(started by G.P. di Giovanni and A. Savoy-Navarro now continuing with N. Ershaidat and soon A. Savelyeva and V. Saveliev)
B → J/ψ K*0 competitive results with BaBar/Belle (France)
B → J/ψ Φ, ψ(2S) Φ (KISTI)
B → J/ψ Φ, using new PID (dE/dx andTOF) and TTT (Two Track Trigger) => sin2βs (France)
=> The Bs sector is crucial physics for searches beyond standard model.
CDF-LIA, FKPPL in Lyon, 2009 29