D0 Mixing - KEK · 2008. 12. 12. · B. Golob, Ljubljana Univ. D0 Oscillations 2 SuperBelle, KEK,...

B. Golob, Ljubljana Univ. D0 Oscillations 1 SuperBelle, KEK, Dec 2008

B. GolobUniversity of Ljubljana,Jožef Stefan Institute

&Belle Collaboration

D0 Mixing@ SuperBelle

Universityof Ljubljana

“Jožef Stefan” Institute

Outline1. CP states2. Wrong sign (non-CP)3. t-dependent Dalitz4. Average5. Constraints on NP6. Prospects & Summary


1. D0 →KK/ππDecays to CP eigenstates

K+K-/π+π-and K-π+ratio

1st evidence for D0 mixing

+

)%25.032.031.1( ±±=CPyBelle, PRL 98, 211803 (2007), 540fb-1

BaBar, arXiv:0712.2249, 384fb-1

=

)%13.039.024.1( ±±=CPy

D0 → K+K- / π+π-, CP evenno CPV: CP|D1> = |D1> ⇒ τ=1/Γ1;K-π+: mixture of CP states ⇒ τ=f(1/Γ1,1/Γ2)

yxAy

KKKy

CPVno

M

CP

=−

≈−≡ +−+−

ϕϕ

τπτ

sin2

cos

1)()(

S. Bergman et al., PLB486, 418 (2000)


1. D0 →KK/ππDecays to CP eigenstates

0sincos2

)()()()(

)()()()(

00

00

00

00

CPVno

M

intmixf

dec

fCP

xyAKKDKKDKKDKKDA

aaafDfDfDfDA

=−≈

≈→+→→−→

=

++=

=→Γ+→Γ→Γ−→Γ

=

−+−+

−+−+

Γ

ϕϕ

ττττ

)%08.036.026.0( ±±=ΓA

)%15.030.001.0( ±±=ΓA

BaBar, arXiv:0712.2249, 384fb-1

t-dependentBelle, PRL 98, 211803 (2007), 540fb-1

Belle, arXiv:0807.0148, 540fb-1

t-integratedACPmeas =Aεπ + AFB + ACPf

Aεπ : comparison of tagged/untagged (D*+ →D0π+),D0 →K-π+AFB: asymmetric f(cosθCMS)

)%13.034.000.0( ±±=KKCPA

)%11.030.043.0( ±±−=KKCPA

ACPKK ACPππ

AFBKK AFBππ

|cosθCMS| |cosθCMS|

|cosθCMS||cosθCMS|

BaBar, PRL 100, 061803 (2007),

386fb-1


D0 →KK/ππSystematics breakdown

[ ]22

0

2 %10.0/%39.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yCPσ

[ ] 22

0

2 %06.0/%33.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=Γ

��Aσ

�0=540 fb-1

Belle, PRL 98, 211803 (2007), 540fb-1

largest contributions (yCP):acceptance: 0.12% scalingequal t0 assumption: 0.14% scalingbkg signal/sideband diff.: 0.09% non-scalingvariation of select.: 0.11% scalingtotal: 0.25%non-scaling: 0.10%

scalingnon-scaling

Aεπ stat.Aεπ binningtotal:non-scaling: 0.06%

0.09%0.05%0.33%

largest contrib. σ(ACPKK):

[ ] 22

0

2 %06.0/%32.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��ACPσ


D0 →KK/ππProjected sensitivity

[ ]22

0

2 %10.0/%39.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yCPσ

[ ] 22

0

2 %06.0/%33.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=Γ

��Aσ

�0=540 fb-1

σ(yCP)[%]

σ(AΓ)[%]

� [ab-1]

16 ab-1

8 ab-1

x ab-1 σstat=σsyst


2. D0 →KπWS decays (non-CP)

D*+ → D0 πslow+ D0 → D0 → K+ π-

DCS decays ⇒ interference;

t

mixinterf

DDCS

D etyxtyRR

tDK

−

−+

⎥⎥⎥

⎦

⎤

⎢⎢⎢

⎣

⎡+

++

∝

222

.

20

4'''

)(π

δδδδ

sincos'sincos'

xyyyxx

−=+=

t-dependence to separate DCS/mixed

BaBar, PRL 98, 211802 (2007), 384fb-1

1st evidence for D0 mixing

1σ3σ

5σ

likelihoodcontours

3.9σ

Belle, PRL 96, 151801 (2006), 400fb-1

δ: unknown strong phase DCS/CF

3.8σ 1σ

3σ

CDF, PRL 100, 121802 (2008), 1.5fb-1

)%31.044.097.0('10)21.030.022.0(' 32

±±=⋅±±−= −

yx

)%06.0('

10)18.0('

39.040.023.021.0 32

±=

⋅±= −

y

x)%76.085.0('

10)35.012.0(' 32

±=⋅±−= −

yx

likelihoodcontours

95% FC confidence region


largest contrib.:Δx’2, Δy’ [σstat]

+0.3 -0.2 p* variation ±0.2 ±0.2 fixed decay-t parameters+0.2 -0.2 σt effect on fractions±0.3 ±0.3 total scaling ±0.5 ±0.5 total±0.4 ±0.4 non-scaling

D0 →Kπ

scales with data/MC

[ ]232

0

32

2' 1009.0/1023.0 −− ⋅+

⎥⎥⎦

⎤

⎢⎢⎣

⎡ ⋅=

��xσ [ ] 2

2

0

2' %16.0/

%42.0+

⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yσ

�0=400 fb-1

scales with data

[ ] statisyst m σσ 2/12∑=σsyst ≈ 0.5 σstat

scales with data

[ ] 22

0

2 %7.1/%4.4

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��ADσ assumed same fraction of scaling/non-scaling

systematics as for x’2

Belle, PRL 96, 151801 (2006), 400fb-1

Systematics breakdown


D0 →Kπ

�0=400 fb-1

σ(x’2) [10-3]

σ(y’) [%]

� [ab-1]

Projected sensitivity

[ ]232

0

32

2' 1009.0/1023.0 −− ⋅+

⎥⎥⎦

⎤

⎢⎢⎣

⎡ ⋅=

��xσ

[ ] 22

0

2' %16.0/

%42.0+

⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yσ

[ ] 22

0

2 %7.1/%4.4

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��ADσ



3. D0 →KSππt-dependent Dalitz analyses

different types of interm. states;CF: D0 → K*-π+DCS: D0 → K*+π-CP: D0 → ρ0 KS

if f = f ⇒ populate same Dalitz plot; relative phases determined (unlike D0 → K+π-);

t-dependence:regions of Dalitz plane →specific t dependence f(x, y);

[ ][ ]titi

titi

S

eemmpq

eemm

tDKtmm

21

21

),(21

),(21

)(),,(

22

22

022

λλ

λλ

ππ

−−+−

−−+−

−++−

−

++

=≡

A

A

M

λ1,2=f(x,y);

D0 →KS π+π-

access directly

x, y

D0→f

D0→f

rad

pq

yx

)09.024.0(

86.0/

30.028.0

09.010.0

29.030.0

14.010.016.013.0

)%24.033.0()%29.080.0(

±±−=

±±=

±±=±±=

ϕ

Belle, PRL 99, 131803 (2007), 540fb-1

D0 →KS π+π-most accurate x


largest model dependence [10-4]: Δx Δy

-10.4 +0.1 K* DCS/CF + 6.9 -2.7-5.1 -4.3 Γ(q2) const.

---------------------------------+10 +6 Total model dep. -14 -8

experimental (major sources): Δx Δy

+7.6 -7.8 p* variation -5.6 -5.7 Dalitz pdf for bkg. from

different t bins -----------------------

+9 +8 Total experimental-7 -12

D0 →KSππ

better underst. of DCS/CF;arbitrary ½ of uncertainty takenas scaling;all other model dependencenon-scaling

±10 ± 7 model non-scaling

all scaling

±10 ±7 total non-scaling

[ ] 22

0

2 %10.0/%31.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��xσ

[ ] 22

0

2 %07.0/%26.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yσ

�0=540 fb-1

Belle, PRL 99, 131803 (2007), 540fb-1Systematics breakdown


model dependence: Δ|q/p| Δφ [rad]

±0.08 ±0.06

experimental: Δ|q/p| Δφ [rad]

+0.06 +0.06 p* variation +0.03 -0.05 bkg. decay t parameters

D0 →KSππ

±0.08 ±0.06 model non-scaling

scales with data/MC

±0.08 ±0.06 total non-scaling

[ ] 22

0

2|/| 08.0/

30.0+

⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��pqσ [ ] 2

2

0

2 06.0/

30.0 radrad +⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��ϕσ

�0=540 fb-1

scales with data/MC



D0 →KSππ

[ ] 22

0

2|/| 08.0/

30.0+

⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��pqσ

[ ] 22

0

2 06.0/

30.0 radrad +⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��ϕσ

�0=540 fb-1

σ(x) [%]σ(y) [%]σ(|q/p|)σ(φ) [rad]

� [ab-1]

[ ] 22

0

2 %10.0/%31.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��xσ

[ ] 22

0

2 %07.0/%26.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yσ

Projected sensitivity

7 ab-1

7 ab-113 ab-1



4. AverageHFAG χ2 fit

)%8.01.0(049.0004.0

054.0894.0

)%003.0336.0(9.46.24

)%064.0813.0()%095.0832.0(

±−=±−=

±=

±=°±°=

±=±=

D

D

K

Arad

pqR

yx

ϕ

δ π

1, 2, 3 σ @ 50 ab-1

E. Barberio et al. (HFAG), arXiv:0808.1297& http://www.slac.stanford.edu/xorg/hfag/

50 ab-1

only KK/ππ, Kπ and Ksππprojected sensitivities included


Average

)%8.01.0(049.0004.0

054.0894.0

)%003.0336.0(9.46.24

)%064.0813.0()%095.0832.0(

±−=±−=

±=

±=°±°=

±=±=

D

D

K

Arad

pqR

yx

ϕ

δ π

HFAG χ2 fit

E. Barberio et al. (HFAG), arXiv:0808.1297& http://www.slac.stanford.edu/xorg/hfag/

1, 2, 3 σ @ 50 ab-1

50 ab-1

only KK/ππ, Kπ and Ksππprojected sensitivities included


5. Constraints on NPconstraints from mixing

existing constraints already now greatly improved for many NP models;example of R SUSY:

E. Golowich et al., PRD76, 095009 (2007)

D0 D0iL�~

iL�~k

Rd kRd

D0 D0iL�kR

d~

iL�

kRd~

|x|

R couplings R couplings

kRdm~

[GeV]

50 ab-1

50 ab-1


Constraints on NPconstraints from CPV:SCS decays (probing penguins);small in SM, small DCPV;

SUSY: squark-gluino loops;

CF: c → sdu (K-π+)SCS: c → qqu (q=s, K+K-)DCS: c → dsu (K+π-)

c uW±

d, s, bVcq Vuq

g q

q

Y. Grossman et al., PRD75, 036008 (2007)

values of ˜m and m(g˜ ) for whichrf=1%

constraint from mixing|M12|

m(g˜ )

contrib. to ΔC=1 enhancedcompared to ΔC=2 by m(g˜ )/mc⇒ sensitivity of mixing to this contrib.

small compared to sensitivity of afdir

SMf

NPff

ffff

dir

fdirCP

AArra

aAA

/sinsin2

=

==+Γ

δϕ


Constraints on NPconstraints from CPV:squark-gluino loops contribution

)%34.011.0(sinsin2

±−=== fff

fdir ra δϕ

Belle, arXiv:0807.0148, 540fb-1

BaBar, arXiv:0712.2249, 384fb-1Belle, PRL 98, 211803 (2007), 540fb-1

BaBar, PRL 100, 061803 (2007), 386fb-1

if φf, δf ∼ �(1)all shown values excluded (rf=1%)

Y. Grossman et al., PRD75, 036008 (2007)

m(g˜ )50 ab-1: σ(adirKK)=0.10%

mmLRuc

~/2 ~~δ

values of ˜m and m(g˜ ) for whichrf=1%

constraint from mixing


Notes

@50 ab-1: σ(x), σ(y) ∼0.05-0.1%, σ(|q/p|), σ(φ) ∼ 0.05, σ(AD) ∼ 0.5-1%

most D0 oscillation studies systematics dominatedneed very detailed studies

detector induced charge asymm.decay t bias (detector alignment)...

obtaining stringent constraints on NP models, useful to identify possible NP signals from LHC

CPV parameters sensitivity not over full SM rangemore modes (KsKK, πππ0,....)

common systematics (Dalitz models)


Super τ charm factorySummary on D0 mixing at Super τ charm factory, Novosibirsk

Super-B factory at initial stage σ(x), σ(y) ~ �( 0.1%)σ(ACP) ~ �(0.1%);δKπ precisely determined from combination of measurements;

RM, y @ charm factory of lower accuracy than @ B factory(unless t-dependent meas. with asymmetric collider);

various options for CPV;several competitive or better, and complementary to B-factory(including D0D0 with C=+1);many other possibilities (Dalitz studies, triple product correlations, T-odd moments, ...)


Phenomenology bckupDCPV in SCS decays to CP states:

[ ][ ])(

)(

1

1CPfCPf

CP

TCPf

CPCP

CPfCPf

CP

TCPf

CPCP

if

iTff

if

iTff

ereAA

ereAAΦ−−

Φ+

+=

+=δϕ

δϕ

ffff

dir

fdirCP

fdirintmixCP

intmix

raaAA

aaaAaaA

δϕ sinsin2

)(

==+

++=+−≈

Γ

Γ�(10-2) contrib. of adirf

M12 for D0:

⎟⎟⎠

⎞⎜⎜⎝

⎛+⎟

⎠⎞

⎜⎝⎛+

Γ= 2

22

12 121

2 yxAxM MD G. Raz, PRD66, 057502 (2002)


Mass insertions bckup

mass insertion approxim. (MIA): replace sum over all possible internal propagators and mixing at the vertices, with a single off-diagonal mass insertion in basis where all gauge couplings are diagonal; MIA: Taylor expanssion in mass-squared differences between intermediate particles w.r.t. chosen mass m;

example: SUSY contrib. to K0 mixing

( )

∗∗

∗∗

∑

∑

ΔΔ∝

−=Δ

ΔΔ≈∝

dj

nm

nj

dj

di

mi

dimn

Kii

nm

nj

mimnjig

jigdj

dj

di

di

K

ZmZZmZCMmmm

mmCmmmJmmmJZZZZM

1,

221

2212

222,

222224

2224121212

)~()~(

~~~

)~()~()~,~,~()~,~,~(

mixing anglesqq ~−


D0 →KK/ππ bckup

scales with MCbetter detect. (MC) desc.

scales with data/MCscales with data/MCscales with data/MC

total non-scaling 0.10% 0.06%


[ ]22

0

2 %10.0/%39.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yCPσ [ ] 2

2

0

2 %06.0/%33.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=Γ

��Aσ �0=540 fb-1

Belle, PRL 98, 211803 (2007), 540fb-1


D0 →KK/ππ bckup

scales with data


[ ] 22

0

2 %06.0/%32.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��ACPσ �0=540 fb-1

q shape difference D0/D0bkg. side/signal windowrnd πs bkg.

Aεπ stat.Aεπ binning

fit binning3/4 layer SVD

0.02%0.01%0.03%

0.09%0.05%

0.03%0.01%

source σ(ACPKK) Belle, arXiv:0807.0148, 540fb-1


D0 →KK/ππ bckupSystematics breakdown

Belle, PRL 98, 211803 (2007), 540fb-1

acceptance: fit generated t for selected evts.;constant within MC stat.

equal t0: t0 diff KK/Kπ/ππ from MC, including missaligned SVD; equal within MC stat.

diff. bkg. signal/sideband:

)min()min(:

,:

,:

11

)1(0

)1()(

'

'

0

0

bbsbsbss

sbsbsbsbs

bbbbs

sb

s

bss

bsss

ppselectionsideband

ttptsideband

ttptwindowsignal

ppp

tptt

tptpt

ττττ

τττ

τττ

τ

τ

Δ−Δ=−

−=ΔΔ+=

−=ΔΔ+=

⇒


model dependence [10-4]: Δx Δy

-10.3 +0.1 K*0(1430) DCS/CF -15%+ 6.9 -2.5 K*2(1430) DCS/CF -30%-1.6 -0.9 K*(1410) DCS & CF -20%

---------------------------------+10 +6 Total model dep. -14 -8

experimental (major sources): Δx Δy

+7.6 -7.8 p* variation -5.6 -5.7 Dalitz pdf for bkg. from

different t bins -----------------------

+9 +8 Total experimental-7 -12

D0 →KSππ bckup

better underst. of DCS/CF;arbitrary ½ of uncertainty takenas scaling;all other model dependencenon-scaling

±10 ± 7 model non-scaling

scales with data/MC

all scaling

±10 ±7 total non-scaling

[ ] 22

0

2 %10.0/%31.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��xσ

[ ] 22

0

2 %07.0/%26.0

+⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yσ

�0=540 fb-1

Belle, PRL 99, 131803 (2007), 540fb-1Systematics breakdown


D0 →KSππ bckup �0=540 fb-1Belle, PRL 99, 131803 (2007), 540fb-1Systematics breakdown

model error

better underst. of DCS/CF;arbitrary ½ of uncertainty takenas scaling;rest non-scaling


D0 →KSππ bckup �0=540 fb-1Belle, PRL 99, 131803 (2007), 540fb-1Systematics breakdown

exp. error

all major sourcesscaling


Systematics bckup


1. Phenomenologyx and y

D0 D0K+

K-

I.I. Bigi, N. Uraltsev, Nucl. Phys. B592, 92 (2001);A.F. Falk et al., PRD69, 114021 (2004)

W+

W-D0 D0

The duration of passion is proportionate with the original resistance of the woman.H. de Balzac (1799 -1850)

unique for D0’s: down q’s loop; mixing: 30 years after discovery

222** )( dsudcdcsus mmVVVV −∝DCS SU(3) breaking

d,s,b

d,s,b

)10(|||,| 2−≤ �yx)10(|~| 5−�xdifficult to estimate


D0: first two quark generations;CKM elements ≈ real;

using CKM unitarity:

bellow current exp. sensitivity;signals New Physics

1. PhenomenologyCP violation

Vcs

Vus*

D0 K-

K+

)(VVVV

Df

Df-

uscs

ubcb 3*

*

0

0

10~arg �ℑ≈⎟⎟

⎠

⎞

⎜⎜

⎝

⎛

)(0

0

0

0

0

0

2/1)2/1(

),2

1(,2

1

,

ϕδ −−

++

−≡

+≡+≡

≡

fi

D

DM

MD

D

eA

RADf

Dfpq

ApqA

Df

Df

RDf

Df

parameterization:RD ≠1: Cabbibo suppression

AD ≠0: CPV in decayAM ≠0: CPV in mixingφ ≠0 : CPV in interference


2. MeasurementsE) ψ(3770) →D0D0

at threshold D0D0 in C=-1 state ⇒effective Br’s depending on mixing param.:

y, RM=(x2+y2)/2, √RDcosδ

S±: CP eigenstatese-: Xeνfit to set of single and double Br’s

Br(D0D0 →fi/fj)Br(D0 →fi)Br(D0 →fj)

Br(D0D0 →fiX)Br(D0 →fi)

single D0reconstr.

both D0reconstr.

)1()1(

)(

)(),(

2

2

221

yBrBry

eDBr

eDBreDSDBr

eSS

S

−≈+Γ→Γ

=

=Γ

→Γ=→→

++

++

measured from ST rates

uncorrelatedproduction

uncorrelatedproduction

Cleo-c, PRD78, 012001 (2008), 281pb-1

(RWS=Γ(K+π-)/Γ(K-π+))


3. Prospects and summaryA) Mixing parameters

Cleo-c results improved signif. with higher stat.;(all estimates based on )

x, y related measurements of similar or better accuracy at Super-B with modest lumin.;

δ already constrained with reasonable accuracy from combination of x’2, y’, x, y meas.;

σ(yCP) [%] B

σ(y) [%] Bσ(x) [%] B

σ(RM) [10-3] charmσ(x’2) [10-3] B

0.5 5.0

� [fb-1]

� [ab-1]

σ(y) [%] charm

0.5 5.0

� [fb-1]

� [ab-1]

� [fb-1]

σ(√RDcosδ) [10-2] charm

Prediction is very difficult, especially of the future.

N. Bohr (1885 - 1962)

Cleo-c, PRD78, 012001 (2008), 281pb-1


3. Prospects and summaryA) Mixing parameters

asymmetric factory at ψ(3770):

for same as at Υ(4S) ⇒ γβ~2 (0.42 at Belle), E(e-/e+)=8 GeV/0.45 GeV (8 GeV/3.5 GeV at Belle);

resolution: σresD ~ σresB (βγB/βγD) ~0.3 ps ~τD0

N(S+K-π+, S+e-)~1300 @ 281 pb-1

σy~0.1% with 2 ab-1 (stat. only)

[ ]

NNtt

tyt

etytytd

fSDDd

resty

t

8~||||

8||;1||

sinhcosh)(

22222

2

||00

σσσ

+Δ−Δ≈=

≈Δ+≈Δ

Δ+Δ∝Δ

→Γ

Δ

Δ−+


3. Prospects and summaryB) CPV parameters

various options at ψ(3770);decays to same sign CP eigenstates:(assuming no direct CPV)

suppressed by RM; not feasible;

� [ab-1]

σ(AΓ) [%] Bσ(|q/p|) Bσ(φ) [rad] B

160

60

00

0

2

2

102.1~104/;/

1)(2)(2

)(sin

sin)(2)()(

−++++++

++++

+++

+

+++

++++

+

++

⋅⋅⇒⋅==



various options at ψ(3770);untagged asymmetry:

ACP linear in CPV and mixing param.,feasible (stat. only); systematics from charge dependent ε asymm.?also possible at B-factories

022

200

0

0000

0000

sin4)(

/2)(

1sin2

)(sin

sinsin2cos2

sinsin2

)()()()()()()()(

��

��

yR

NN

yR

yRxAyRA

KDKDKDKDKDKDKDKDA

D

ACP

ACP

K

KACP

D

ACP

DM

DCP

CP

δσ

σσσ

δσϕσ

ϕδϕϕδ

ππππππππ

π

π =≈

0.2 0.5 0.9 sinδ

�[fb-1]

1400

1000

600

200300 fb-1

current δ

RD, y uncertainty



D0D0 in C=+1 state (D0D0 γ);tagged asymmetry:

MMCCP

MCCP

ARAbn

AxAyeSeSeSeSA

≈

=−≈Γ+ΓΓ−Γ

=

−=

Γ++

−+

++

−++=

1

1

:..

sincos2)()(

)()( ϕϕ



various options at ψ(3770);CPV in mixing:

ACP linear in CPV param.,feasible (stat. only); systematics from e- spectrum extrapolation (cancels in ACP)?σ(AM)~1% with 300 fb-1 sensitivity better than at Super-B;

)(4))(()(5.0)(

2)()()()(

0000

0000

±±

±±

−−++

−−++

≈≈

−≈→Γ+→Γ→Γ−→Γ

=

eeNeeNAA

AAeeDDeeDDeeDDeeDDA

CPM

MCP

CP

σσσ

σ(AΓ) [%] Bσ(|q/p|) Bσ(φ) [rad] B

� [ab-1]



various options at ψ(3770);direct CPV:

ACP linear in CPV param.,feasible (stat. only); systematics from e- spectrum extrapolation (cancels in ACP)? sensitivity better than at Super-B;

a complete overview of physics cases (for BES-III)can be found in

)())(()(2)(

2

)()()()(

0000

0000

±−+

±−+

++

−+

++

−+

≈≈

≈

→Γ+→Γ→Γ−→Γ

=

eKKNeKKNAA

AA

eSDDeSDDeSDDeSDDA

CPD

DCP

CP

σσσ

σ(AD) [%] charmσ(AD) [%] B

0.5 5.0

� [fb-1]

� [ab-1]

K.T. Chao, Y. Wang, editors, arXiv:0809.1869


Systematics bckupψ(3770) →D0D0

[ ]22

0

2cos 006.0/

036.0⊕

⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��δσ R[ ]

2

2

0

2 %2.1/%1.6

⊕⎥⎥⎦

⎤

⎢⎢⎣

⎡=

��yσ

�0=281 pb-1

assume sensitivity ony is mainly due to S±e-√RDcosδ is mainly due to S±K-π+RM is mainly due to K-π+K-π+

calculate fraction of non-scaling syst. on DT yields in total relative error:S±e- (y) σ(non-scaling)/σ(total)=15% extrap. of e- momentumS±K-π+ (√RDcosδ) σ(non-scaling)/σ(total)=15% FSR, sideband subtr.K-π+K-π+ (RM) σ(non-scaling)/σ(total)=2.4% FSR

[ ]232

0

32 1004.0

/107.1 −− ⋅⊕

⎥⎥⎦

⎤

⎢⎢⎣

⎡ ⋅=

��RMσ

Cleo-c, PRD78, 012001 (2008), 281pb-1


δ bckupψ(3770) →D0D0

δ constraintsaveragedirect meas.(fit w/o external input)

0 1 2 3 4 5 δ [rad]

1.0

0.5

0

-0.5

-1.0

y’=y

cosδ

-xsi

nδ [%

]

y’ measured

δm

easu

red

0 1 2 3 4 5 δ [rad]

cosδ

1

0

-1


Phenomenology bckup

∑ +−+=Γ

−−=Δ−=Δ

−=Δ

n nD

Cw

Cw

D

Cw

D iEMDHnnHD

MDHD

MiM

ε

0110020

12 21

21)

2(

055

02

222**

2

2020 |)1()1(|)(

4DcucuD

mmmVVVVGDHDc

dsusudcdcs

FCw γγγγπ μ

μ −−−

=−=Δshort distance:

DCS SU(3) breakingG. Burdman, I. Shipsey, Ann.Rev.Nucl.Sci. 53, 431 (2003) |x| ~ �(10-5)

long distance:

absorptive part (real interm. states) ⇒ ydispersive part (off-shell interm. states) ⇒ x D

0 D0K+

K-

I.I. Bigi, N. Uraltsev, Nucl. Phys. B592, 92 (2001);A.F. Falk et al., PRD69, 114021 (2004)

|x|, |y| ~ �(10-2)D0 mixing: rare process in SM;possible contrib. from NP

x and y in SM2nd order perturb.:

c

u

u

c

d, s, b d, s, bW+

W-D0 D0

Vci*

Vcj

Vuj*

Vui


K+π-π0 bckup BaBar, arXiv:0807.4567, 384fb-1

D0 →K+ π-π0

ππππ

ππππδδδδ

KK

KKxyyyxx

sincos''sincos''

−=+=

BaBar, Lepton Photon 07, 384fb-1

no mixing point 0.8% C.L.

δKππ: unknown strong phase shiftDCS/CF

t

mix

f

interf.

ffff

DCS

f

etyxA

txyAA

AtDK

−

−+

++

+−+

+∝

]

||[

222

2

2200

4''''||

)sin''cos''(||||

)(

δδ

ππseparate WS/RS Dalitz distributions;

t-distrib. analogous to D0 →K+ π-;

RS t-integratedDalitz analysis;WS Dalitz analysis;


K+K- / π+π- bckup Belle, PRL 98, 211803 (2007), 540fb-1

Fitsimultaneous binned likelihood fit to K+K- /K-π+/π+π- decay-t, common free yCP

)(')'(/' tBdttteNdtdN t +−= ∫ − Rττ

R : ideally each σi Gaussian resol. term with fraction fi;

: described by 3 Gaussians ⇒

∑ ∑= =

−=−N

i kikki tsttGwftt

1

3

10 ),,'()'( σR

τ = 408.7±0.6 fs

event-by-event σt

K-π+

trec-tgen/σt

parameters of R depend slightlyon data taking conditions


K+K- / π+π- bckup

equal t0 assumption

ΔyCP=t0CP - t0Kπ / τKπ

from MC cocktail, includingrunning periodswith slight misalign.of SVD

Belle, PRL 98, 211803 (2007), 540fb-1


ψ(3770) →D0D0 bckup

( )[ ]

22112

00

2100

00,,

200

)(2

1,

;,,)(;)(

DjDiDjDiijDD

DDDD

DjiDjiAAAAAAijDD

jiji

jiji

−=→Γ

⇒±=

≡

−=→ΓD0, D0 in

anti-symmetric state


Triple product correl. bckupD →K*(p1,ε1)K*(p2,ε2)

T(pi,εi) = -pi,εi;

but AT ~ sin(φ+δ)φ: weak phaseδ: strong phase;⇒

)0)(()0)(()0)(()0)((

211211

211211

×⋅×⋅

=εεεεεεεε

pNpNpNpNAT

:2

T

TTCPT

A

AAA +=

asymmetry of conjugated process

ATCP ~ sinφcosδn.b.: ACPdir ~ sinφsinδ


T-odd moments bckupD →KKππ

α: angle between KK and ππ planes;

::

sincossincos

sincossincos

sincossincos

33

2,12,1

,

32

22

1

32

22

1

Γ≠ΓΓ≠Γ

−⎯⎯ →⎯

Γ+Γ+Γ=Γ

Γ+Γ+Γ=Γ

αααα

ααααα

ααααα

TCPdddd

direct CPV;CPV;

D0 Mixing�@ SuperBelle1. D0 →KK/pp1. D0 →KK/ppD0 →KK/ppD0 →KK/pp2. D0 →KpD0 →KpD0 →Kp3. D0 →KSppD0 →KSppD0 →KSppD0 →KSpp4. AverageAverage5. Constraints on NPConstraints on NPConstraints on NPNotesSuper t charm factoryPhenomenology bckupMass insertions bckupD0 →KK/pp bckupD0 →KK/pp bckupD0 →KK/pp bckupD0 →KSpp bckupD0 →KSpp bckupD0 →KSpp bckupSystematics bckup1. Phenomenology1. Phenomenology2. Measurements3. Prospects and summary3. Prospects and summary3. Prospects and summary3. Prospects and summary3. Prospects and summary3. Prospects and summary3. Prospects and summarySystematics bckupd bckupPhenomenology bckupK+p-p0 bckupK+K- / p+p- bckupK+K- / p+p- bckupy(3770) →D0D0 bckupTriple product correl. bckupT-odd moments bckup

D0 Mixing - KEK · 2008. 12. 12. · B. Golob, Ljubljana Univ. D0 Oscillations 2 SuperBelle, KEK,...

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Transcript of D0 Mixing - KEK · 2008. 12. 12. · B. Golob, Ljubljana Univ. D0 Oscillations 2 SuperBelle, KEK,...