b-factory constraints on possible new physics at the lhc
DESCRIPTION
v. S.L. Olsen U of Hawai’i 高能所 北京. B-factory constraints on possible New Physics at the LHC. Academia Sinica (Taipei) June 12, 2007. Outline. Implications of recent D 0 -D 0 mixing results CPV measurements with Penguins Charged Higgs limits Light dark matter searches. - PowerPoint PPT PresentationTRANSCRIPT
vB-factory constraints on possibleNew Physicsat the LHC
S.L. OlsenU of Hawai’i高能所 北京
Academia Sinica (Taipei) June 12, 2007
Outline
• Implications of recent D0-D0 mixing results
• CPV measurements with Penguins
• Charged Higgs limits
• Light dark matter searches
SUSY & D0-D0 mixing
SUSY “Flavor Problem”K0-K0 mixing
SM: NP (MSSM):
QCD-verticesEW-vertices
6x6 matrix2nd order EW:Δm 3 x 10-12 MeV Potentially huge:
effects not seen
How to make Δm small?PLB 309, 337 (1993)
Quark-Squark “Alignment”
Invoke a horizontal symmetry that results insmall values for the down-type squark mixing
This fixes up-type squark mixing elements cosC (~0.2)
Expect large effects in D0-D0 mixinge.g. Δm ~ 6x10-11 MeV
Nir & Raz PRD 66, 035007 (2002)
Neutral D meson phenomenology
SM: CPV is very small: q ≈ p ≈1/2
Recent D0-D0 mixing results (I)
D*+ + D0 D0 K+-
pion charge tagsthe D0 flavor
DCS decays
“Wrong sign” (WS) decays
Use t-dependence to separate WS from DCS
decays
mixing evidence from WS decays
BaBar excludesno-mixing at 3.9s
strong phase
D0 = (1/2) (D1 + D2)
K
D2-D1 lifetime diff:
K
KK KK,
Lifetime measured w D0Kdecays = <1 + 2>/2
“ “ w D0KK & decays = 1
x
Recent D0-D0 mixing results (II)
Belle measurement of ycp
hep-ex/0703036accepted by PRL
For CPV = 0: yCP = y
Recent D0-D0 mixing results III
D*+ + D0 D0
pion charge tagsD0 flavor @ t=0
Dalitz analysis of D0KS decays
KS
t-dependent interference
D0 decay D0 decay
Dalitz analysis of D0KS
D0K*-
D0K*++
K*+
/K*-
Results
95% CL contour
x = (0.80 0.29 0.17) % y = (0.33 0.24 0.15)%
= (410.3 0.3) fs
HFAG YCP (0,0) excluded at 2.7level
Commentsalà Y. Nir hep-ph/0703235v2
• D0-D0 mixing probably observed in ΔΓ– y = (Γ1-Γ2)/2Γ = (1.4 ± 0.4) x 10-2
• Mass difference still not seen– x < 0.015 @ 95% CL– Δm < 1.2 x 10-11 MeV (CP conserved)– Δm < 2.2 x 10-11 MeV (CP violated)– ~factor of 3 below m≈1TeV q/g expectation~ ~~
~~
How to make m small?
Making ΔM small in the MSSM
• fine-tune the squark mixing terms– SUSY is supposed to save us from fine-tuning
• make the squark masses degenerate GIM– unlike ordinary quarks: mt/mu ~ 105
• raise the SUSY mass scale ( ~few TeV)– not much fun for LHC experimenters
CPV
CPV in the SMcomplex terms in the CKM quark-flavor mixing matrix
Wolfenstein
bu (3)
td (1)
B0
B0B0
Vcb
VtbV*
V*Vtb
J/
J/
KS
KS
sin21 from BfCP + BBfCP interf.
V*2
sin21
td
td
td
Sanda, Bigi & Carter:
no CP phase
What do we measure?
t z/cβγ
Flavor-tag decay(B0 or B0 ?)
J/
KS
B - B
B + B
e
e
more B tags
more B tags
zt=0
fCP
(tags)
sin21
This is for CP=-1; for CP=+1, the asymmetry is opposite
Asymmetric energies
Results (2006)Belle BaBar
LP2001 Rome
sin21() history
CKM with (mostly) trees
SM+CKM is “correct” at tree level
CKM Global Fit (Sep.2006)
Next Step
Check the Unitary Triangle with Penguins
bs FCNC decay
SM FCNC: NP:
)(or )( of effectsExpect 2
2
NP
top
NP
top
M
MO
M
MO
i.e. > 0.1 for MNP accessible @ LHC
~
~ s~
x
b
g
t
c~
x
t
-~
~
2nd-order Weak process
QCD-verticesEW-vertices
at least
V
2nd-order QCD processhuge effects are possible
(but not seen)
This mixing matrix is 6x6(lots of CP phases)
sin21 with bs penguins (SM)Example:
no CP phase
SM: sin21 = sin21 from BJ/ KS (bc c s)eff
Vtd
Vtd
+
1
B B
, ’,
1
, ’,
_
*
*
)(NP
top
M
MO
B0 'K0
(bkg subtracted)
B0 mass B0 momentum
535MBB
hep-ex/0608039hep-ex/0608039
’ Ks() 794 36
(2) Ks() 363 21
(3) Ks() 100 11
Ks()103 15
() Ks() 62 9
Total 1421 46
’() KL 392 37
() KL 62 13
Total 454 39
K0KS K0KL
TCPV in B0'K0
“sin21” = 0.64 0.10(stat) 0.04(syst) A = 0.01 0.07(stat) 0.05(syst)
“sin21” = 0.64 0.10(stat) 0.04(syst) A = 0.01 0.07(stat) 0.05(syst)
Consistent with the SM Consistent with Belle 2005
(Belle 2005: “sin21” = +0.62
First observation of TCPV (5.6in a single b s mode
Consistent with the SM Consistent with Belle 2005
(Belle 2005: “sin21” = +0.62
First observation of TCPV (5.6in a single b s mode
t distribution and asymmetry
'KS and 'KL combined background subtracted good tags t –t for 'KL
535MBB
hep-ex/0608039hep-ex/0608039
B0 K0
B0 massB0 momentum
(bkg subtracted)
KK, KS
KK, KS
KSKL, KS
114 17 KL signal
114 17 KL signal
2461840922730721 KS signal
2461840922730721 KS signal
hep-ex/0608039hep-ex/0608039
535MBB
KK
K0KS
K0KL
TCPV in B0 K0
“sin21” = 0.50 0.21(stat) 0.06(syst) A = 0.07 0.15(stat) 0.05(syst)
“sin21” = 0.50 0.21(stat) 0.06(syst) A = 0.07 0.15(stat) 0.05(syst)
KS and KL combined background subtracted good tags t –t for KL
t distribution and asymmetry
Consistent with the SM (~1lower) Consistent with Belle 2005
(Belle2005: “sin21” = +0.44
Consistent with the SM (~1lower) Consistent with Belle 2005
(Belle2005: “sin21” = +0.44
unbinned fitSM
535MBB
hep-ex/0608039hep-ex/0608039
2006: 1 with b s PenguinsSmaller than bccs in all of 9 modes
Smaller than bccs in all of 9 modes
Theory tends to predict positive shifts(originating from phase in Vts)
Naïve average of all b s modes
sin2eff = 0.52 ± 0.052.6 deviation betweenpenguin and tree (b s) (b c)
Naïve average of all b s modes
sin2eff = 0.52 ± 0.052.6 deviation betweenpenguin and tree (b s) (b c)
History of sin21
sin21 from bccs decays (2007)
2002
2003
2004
2005
2006
2.6
3.1
3.9
2.8
2.6
0.15
eff
sin
2 1
(b
s d
ecays)
(Belle&
BaB
ar
avera
ge)
~ s~
x
How to make Δsin21 small?
•Tune the squark mixing terms•is there enough freedom to do this?
•Make the squark masses degenerate•invoke a GIM-like mechanism
•Make the SUSY mass scale very high (~few TeV)•not much fun for LHC experimenters
b
g~
eff
Charged Higgs limits from
B
B
Decays w/ “Missing E(>1)”Decays w/ “Missing E(>1)”
B decay constant Lattice QCD
SM :
BSM : sensitive to New Physics from H
B (nearly invisible decays)
N= 680keff.= 0.29% purity = 57%
N= 680keff.= 0.29% purity = 57%
Charged B
(*)0 (*)1/ / / SB D a D
0 0 0/D D sD
Tag-side: Full reconstruction
449M BB
Υ(4S)e (8GeV)
e+(3.5GeV)
B
B
signal signal
4-momentum determined B meson beam !
4-momentum determined B meson beam !
Missingmomentum
Missingmomentum
B candidate event
B results
Hadronic tags
e
First evidence, 3.5
BellePRL97, 251802 (2006).
BaBar results on BD l tags hadron
tags
BaBar combined result:
hep-ex/0608019 Gritsan@FPCP07
Belle measures:
Branching fraction
Product of B meson decay constant ƒB and CKM element |Vub |
Compare with
Babar preliminary
Constraints on H mass
rH=1.130.51
Use known fB and |Vub |
Ratio to the SM BF.2
22
(1 tan )BH
H
mr
m
excluded
excl
uded
Radiative Penguins
b s b sl +l -
New Physics? b s b sl +l -
H-
t
-
~
~
t
-
~
~
Wilson Coefficients
Nakao
NNLO calculation
(29826) x 10-6
M. Misiak et al, hep-ph/0609232, PRL 98,022002(2007)
Theory News
NN
LO
th
eory
Error on BF
Central value of BF
95% CL lower limit on H+ mass from exp and NNLO
M. Misiak et al, hep-ph/0609232, PRL 98,022002 (2007)
BaBar/Belle/CLEO avgM(H+)>295 GeV
300 GeV
Charged Higgs limits from BXs
Combined limits
Determine |C7| from BXs
R7=C7/C7SM
R8
=C
8/C
8S
M
90%CL
SM
NP
SUSY MFV
A.Ali et al. Phys.Rev. D66 (2002) 034002
Get sign of C7 from BK*l+l-
• 357/fb data 386x106 BB pairs
• Electron or muon pair– Charmonium veto
• K*(K+-, Ks+, K+0)|MK – MK* | < 75MeV
• B meson reconstruction• Background suppression
• Signal yield– K*ll 114 13, purity 44%
• Null test sample – K+ll 96 12, purity 57%– K+ll has no asymmetry.
Forward-Backward Asymm: AFB
B
K*
l
l
B
K*
l
l
Forward event Backward event
Fit results for A7/A9 & A7/A10
• Null test with K+ll
• Integrated AFB in K*ll
SM
J/ ’
• Fit to K*ll
SM wins again
Best fit
SM
SMA9/A7
A10/A7
fit resultA7A10 sign flipped (to SM)
A9A10 sign flippedBoth A7A10 and A9A10 signs flipped
Search for “light” dark matter
Dark matter coupled to qq?
for m<mb
Belle’s search strategy
Signature: only in detector & Mrecoil()=m(1s)
Summary
Any “new physics” that is seen at the
LHC is very carefully hidden from the
Flavor Sector
Backup Slides
Parameters are already constrained by KK & DD mixing
Same diagrams contribute
SM:
X X
W+ W-
c d, s u
NP:
X X
g(+) g(-)
c c (s) u (d) u
x
~ ~
~ ~
K & D mixing are consistent with 2nd order SM EW
~ ~
~~
Validate the EECL simulation using double-taggedevents (with on the signal side) Signal reconstruction (purity ~
90%)Extra Calorimeter Energy
MC: B+B–: 494 ± 18 B0B0: 8 ± 2 Combined: 502 ±18
Data: 458
_
SM NP?
)(or )( of effectsExpect 2
2
NP
top
NP
top
M
MO
M
MO
i.e. > 0.1 for MNP accessible @ LHC~
~ s~
x
b
g~
t