29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
1
Review of Hyperon in KTeV
and other recent results
Hyperon beta decays Hyperon radiative decays Kaons rare decays Conclusions
(on behalf of the KTeV collaboration)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
2
The KTeV Collaboration
E. Cheu, J. Hamm, S.A. Tagger, J. Wang - University of Arizona
K. Arisaka, W. Slater, A. Tripathi, S.E.Turner - University of California, Los Angles
R. Barbosa, C. Escobar, P. Gouffon, R. Zukanovich-Funchal - University of Campaninas/University of Sao Paulo
E. Blucher, C. Bown, S. Bright, A. Glasov, G. Graham, J. Graham, R. Kessler, E. Monnier, V. Prasad, B. Quinn, A. Roodman, P.S. Shawhan, N. Solomey, Y.W. Wah, B. Winstein, R. Winston, E. Zimmerman - University of Chicago
A. R. Barker, J. LaDue, P. Mikelsons, U. Nauenberg, P.A. Toale, J.-Y. Wu - University of Colorado, Boulder
E. C. Swallow - Elmhurst College
L. Bellantoni, R. Ben-David, G.J. Bock, S. Childress, R. Coleman, M. B. Crisler, R. Ford, Y. B. Hsiung, D. A. Jensen, P.L. Mcbride, H. Nguyen, V. O’Dell, M. Pang, R. Pordes, E. Ramberg, R. E. Ray, P. Shanahan, R. Tschirhart, H. B. White, J. WhitmoreFermi National Laboratory
K. Hanagaki, S. Hidaka, T. Nakaya, M. Sadamoto, K. Senyo, I. Suzuki, T. Yamanaka - Osaka University
A. Bellavance, M. D. Corcoran - Rice University
I. Albuquerque, S. Averitte, J. Belz, D.R. Bergman, E. Halkiadakis, A. Lath, S. Schnetzer, S. Somalwar, R. L. Stone, R. Tesarek, G. B. Thomson - Rutgers University
M. Arenton, G. Corti, B. Cox, A. Golossanov, K. Hagan, V. Jejer, S. Ledovskoy, A. P. McManus, K. Nelson - University of Virginia
A.Alavi_Harati, T. Alexopulos, A. R. Erwin - University of Wisconsin, Madison
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
3
The KTeV detector
●High resolution CsI calorimeterσE/E<1% at <Eγ>=10GeV, π/e>700
●High resolution spectrometerChamber resolution: ~100 µm
●Large TRDRejection π/e>200
●Photon veto
●Intense beam on BeO target5x1012 protons/mn kaons, hyperons
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
4
Data taking periods
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
5
KTeV Hyperon Program
●Hyperon beta decays: ●ee and (+ anti mode)
●Hyperon radiative decays●eep
●parameters (lifetime, mass)
●Rare decay search,(S=2)●p
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
6
●2 neutral clusters:()
●2 tracks:(p)
●1 high momentum track: (p)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
7
Allowed beta decays
n p
(red arrows)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
8
ee
Signal = 626Signal = 626 +/-+/- 25 events25 events
Background = 60Background = 60 +/- +/- 8 events 8 events
0L
-00
K
pe ,
background
ev
* KTeV first measured B.R = (2.71* KTeV first measured B.R = (2.71 ++ 0.22 0.22 ++ 0.31) x 100.31) x 10-4-4 PRL 82; 3751; (1999) PRL 82; 3751; (1999)
Theoretical (SU3) predicted B.R = (2.61 Theoretical (SU3) predicted B.R = (2.61 ++ 0.11) x 100.11) x 10 -4 -4
B.R = (2.54B.R = (2.54 + + 0.11 0.11 + + 0.16) x 100.16) x 10-4-4 -- --Stat SysStat Sys
--
--
*
--
pee
p
_
_
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
9
Baryon beta decay
● A(pA(pAA) ) B(p B(pBB) + l + ) + l + q = pq = pAA - p - pBB
● Matrix element:Matrix element:M = 2 = 21/21/2 G G <<B B |J|JAAuul l (p(pll) ) vv (p (p))
● V-A currentV-A current
<<BB |J |JAA = u = uB B {{ff11(q(q22)) + i + i ff22(q(q22)/)/MMAA qqv v + + ff33(q(q22)/)/MMAA q q
+ + gg11(q(q22)) + i + i gg22(q(q22)/)/MMAA qqv v + + gg33(q(q22)/)/MMAA q q
uuAA
● =0.98 for p
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
10
g1/f1 = 1.32 ± 0.210.17(stat) ± 0.05(syst)
f2/f1 = 2.0 ± 1.2 ± 0.5
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
11
ee and ee (99)_ ___
1220 ee 105 ee
_ _
KTeV preliminary
KTeV preliminary
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
12
●From 97 data set: 5 Evts
●Normalisation: ee
● Br=(3.5 ± 2.01.6(stat) ± 0.5
1.0(syst))10-6
● 99+97 not enough for form factor,
● Need few hundreds
_
99 data
Mass (p+0)
Mas
s (
+0-
)
• Correct Charge• Wrong Charge• Final Candidates
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
13
Events with:●2 photons
(cluster)● (2 tracks)●mass constraint● from target
M (GeV/c2)
M (GeV/c2)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
14
In the peak:●4045 events●804 background●Norm:
●BR((3.34±.05±.09)x10-3
M (GeV/c2)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
15
= -0.63 +/- 0.08 +/- 0.05
Measurement of
●3 steps process
●Depolarisation of 1/3 for
●Phys. Rev. Lett. 86, 3239 (2001).
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
16
Polarization at 800 GeV
●Reconstruct
●Extract directions x,y,z (in rest frame)
●Ratio for two magnet settings is:
1 + i Pi (cos i)(with i=x,y,z)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
17
Polarization results
****
*
*
_
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
18
evts 33100,1)( N
evts 1063000,130,1)( 0 N
Winter’97 data(Contained 1 cluster data)
00
3-x10)04.094.0()(
)(
oBR
BR
(stat only)
3PDG 10x]16.006.1[BR
Preliminary BR
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
19
ee
KTeV preliminary
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
20
KTeV preliminary
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
21
Kaon rare decay in KTeV
●Results from 1997 data
●Now combined analysis
●2.5 to 3 times more data
●New combined results
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
22
●Double dalitz decay
●Angular distributions sensitive to Scalar/pseudoscalare coupling
●ee masses linked to form factors
●Normalisation is KL-ooo with 2 o dalitz decay
●97: 10506 signal events 52446 normalisation events
●99: 17448 signal events 79640 normalisation events
●97+99: 27954 signal / 132086 norm B(o-e+e-e+e-)/B(o-e+e-)2
= 0.2252±0.0015±0.0059
B(o-e+e-e+e-)/B(o-) = (3.274±0.022±0.197)x10-5
Form factor analysis ongoing, results soon
o-e+e-e+e- from KL-ooo
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
23
● angle of ee plane
●(cos2+Csin2)(SM: = -0.18, C = 0)
●No indication of CP violation
Parity analysis of o**
coupling
KTeV preliminary
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
24
KL-+-
● Br(KL-+-)=(3.62±0.04±0.08)x10-7
● Normalized to KL-+-o
● K*=-0.160-0.028
+0.026
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
25
KL-e+e-
●Br(KL-e+e-)=
(10.13±0.04±0.06±0.29)x10-6
●Normalized to KL-oooD
●93383 Sig. / 5306073 Norm.
●K*=-0.192±0.011±0.009(syst)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
26
Result on K*
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
27
KL-e+e-
+-
●Normalized to KL-+-oD
●93383 Sig. / 5306073 Norm.
●Br(KL-e+e-+-)=
(2.61±0.23±0.18)x10-9
(VMD prediction is 2.34x10-9 )
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
28
KL-e+e-
+-
●No CP violation effect in angular distribution
●Search for lepton flavor violation:
●Br(KL-e±e±±±)<(4.12)x10-11
(90% C.L., preliminary)
●Form factor analysis soon
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
29
Other recent results
●KL-+-e+e-
●5056 ± 71 events
●A=(13.3±1.4±1.0)% (preliminary)
●+ Vector form factor parameters
●KL-o±e-+ :
●Br(KL-o±e-+)<(3.34)x10-10
(90% C.L., preliminary)
29 June 2002 Emmanuel Monnier - C.P.P.Marseille, U. of Chicago BEACH2002
30
Conclusion
●KTeV has produced many results●Hyperon decays
●Kaon rare decays
●High statistic modes
●But KTeV has still a lot to produced from the 99 data set and many results will come out soon…