MeasurementsoftheBsMixing* PhaseatCDFweb.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...

Measurements of the Bs Mixing Phase at CDF

Robert Harr Wayne State University

26 July 2011 R. Harr, Bs Phase at CDF 1

Outline •  Status of the CP violaGon in Bs J/ψ φ analysis •  Bs J/ψ f0(980) branching fracGon and lifeGme •  Measurement of χb •  CP violaGon in Bs φ φ •  Summary


The CDF Detector


muons 0.6 < |η| < 1.0

muons |η| < 0.6

vertex detector

central tracker

1.4T solenoid

BS à J/ψ φ


CP ViolaGon in Bs J/ψ φ Decays


7

!"#$%&'()%&*#%*#+,

-.

/01(2,

! !"

"#$%&'#$()*+&,-) #

#()./)#,)*0-1#2'-1)'$)3-)"-04),5&%%6

$% &'! 7-8)*+4,#2,)*&0'#2%-,)09((#(:)#()'+-)5#;#(:)1#&:0&5)5&4)-(+&(2-

#! %&0:-) #

2%-&0)#(1#2&'#$()$<)7-8)=+4,#2,)>)

1$5#(&(')2$('0#39'#$(<0$5)'$*)?9&0@)

! A(&%$:$9,%4)'$)'+-)(-9'0&%)()

,4,'-56)!"

"#$%&'#$()#()(#

,4,'-5)#,)&22-,,#3%-)'+0$9:+)#('-0<-0-(2-)$<)1-2&4,)8#'+)&(1)8#'+$9')5#;#(:B

7-8)=+4,#2,*&0'#2%-,)C)

DC

E

F-2&4)0&'-)G

SM predicts Gny CP violaGon in Bs mixing.

New physics can have a detectable effect.

Current Status


(rad) s

-1 0 1

)

-1

(ps

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

-1CDF Run II Preliminary L = 5.2 fb95% CL68% CLSM prediction

CDF and D0 originally had ~2σ inconsistencies with SM predicGon, were more consistent with each other..

CDF 5.2 \-‐1 result (summer 2010) is more consistent with SM, difference is ~1σ

An update with (7+) \-‐1

data set is in progress.

BS à J/ψ f0(980)


Interest in Bs J/ψ f0(980) •  This is a P V S decay. •  The decay is S-‐wave – may effect the Bs J/ψ φ analysis when f0 K+K-‐.

•  Measure the B.F. to help constrain effects in J/ψ φ. •  AddiGonally, this final state is CP odd, and neglecGng direct CP violaGon, comes only from BH eigenstate. – LifeGme gives τH. – Can be used to measure CP violaGon without angular analysis.


CDF ObservaGon of Bs J/ψ f0(980)


Flade distribuGon

Rf0/φ = 0.257± 0.020(stat)± 0.014(syst)B(B0

s → J/ψf0(980))B(f0(980)→ π+π−) =(1.63± 0.12(stat)± 0.09(syst)± 0.50(pdg))× 10−4

LifeGme in Bs J/ψ f0(980)


In the absence of CP violaGon, measures the lifeGme of BH state. Simultaneous fit to mass, decay Gme, and decay Gme error.

First LifeGme Measurement

•  Interpret as first direct measurement of τH

•  Compares well to indirect measurements of τH, and theoreGcal predicGons.


τ(B0s → J/ψf0(980)) = 1.70+0.12

−0.11(stat)± 0.03(syst) ps

MEASUREMENT OF χB


χ •  χ is the average mixing probability

•  And is related to R:

•  Difference in average χ from LEP (0.1259±0.0042) and Tevatron (0.147±0.011)

R =N

++ +N−−

NOS


_

_

_

CDF Run I: PRD 69, 012002 (2004)

χb =Γ(B0→ B̄0→ �+X)

Γ(B→ �±X)= fdχd + fsχs

RelaGon of R to χ •  R has contribuGons from mixing, and other decay processes such as – b c µ decays – b ψX, b χcX, and other b cc q decays

•  We account for these effects with a parameter f, determined from simulaGon to be f=0.176±0.011

•  We obtain the relaGon:

R =f�χ2 +(1−χ)2

�+2χ(1−χ)(1− f )

(1− f )�χ2 +(1−χ)2

�+2χ(1−χ) f


_

_

χ Measurement •  Use dimuon triggered data from 1.44/\ of int. lumi. •  Same selecGon requirements as described for ASL measurement.

•  Require that both muons have a hit in one of the two innermost silicon layers – Removes a large fracGon of poorly understood events –  Reduces overall staGsGcs.

•  Fit the OS, ++, and – impact parameter distribuGons simultaneously

•  Determine R from bb component of the fit.


_

Fit Results

OS

++

-‐-‐

1D projecGons of 2D fits


Fit probability 78.5%

χ Result •  R=0.467±0.008 (stat only) •  Varying the templates within their uncertainGes yields a systemaGc error of 0.007

•  R = 0.467±0.011 (stat and syst) •  Yields χ = 0.126 ± 0.008 (0.005 is due to R and 0.006 to f)

•  Compare to LEP average χ = 0.1259 ± 0.0042


_

_

_

BS à φ φ


Angular Variables •  This is a P V V decay – We use the helicity frame with variables φ, θ1, θ2


Fit Data from 2.9 \-‐1 of Lumi.

•  Combined fit to mass and angular variable dists.


)2) (GeV/c-

K+

K-

K+

Mass(K5.3 5.4 5.5

2C

andid

ate

s p

er

10 M

eV

/c

0

10

20

30

40

50

60

70

80

90

-1CDF Run II Preliminary L = 2.9 fb

DataFit

!!"sBBackground

(rad)!0 2 4 6

Ca

nd

ida

tes p

er

0.5

ra

d

0

10

20

30

40

50

60

70

80

90

100-1CDF Run II Preliminary L = 2.9 fb

DataFit

""#sBBackground

1!cos

-1 -0.5 0 0.5

Ca

nd

ida

tes p

er

0.2

4

0

20

40

60

80

100


DataFit

""#sBBackground

2!cos

-1 -0.5 0 0.5

Ca

nd

ida

tes p

er

0.2

4

0

20

40

60

80

100


DataFit

""#sBBackground

|A0|2 = 0.348±0.041 (stat) ± 0.021 (syst) |A|||2 = 0.287±0.043 (stat) ± 0.011 (syst) |Aperp|2 = 0.365±0.044 (stat) ± 0.027 (syst) cosδ|| = -‐0.91+0.15-‐0.13 (stat) ± 0.009 (syst)

fL = 0.348±0.041 (stat) ± 0.021 (syst) fT = 0.652±0.041 (stat) ± 0.021 (syst)

arXiv: 1107.4999

Triple Product Asymmetries

•  TP asym. is T odd violates CP under CPT cons. •  NP enters in interfer. betwn CP even and odd amplitudes •  Result is consistent with zero (SM expectaGon)


u = sinφ cos φ

v = sinφ×sign (cos θ1 cos θ2)

Au = -‐0.007 ± 0.064 (stat) ± 0.018 (syst) Av = -‐0.120 ± 0.064 (stat) ± 0.016 (syst)

New arXiv: 1107.4999

First measurement

Dada and London, Int. J. Mod. Phys. A 19, 2505 (2004)

Summary •  The new χ result is in agreement with the LEP measurements, possibly sedling a long standing difference.

•  First measurement of triple products in Bs φφ decays, consistent with SM expectaGon of zero.

•  First measurement of lifeGme in Bs decay to CP odd eigenstate Bs J/ψ f0

•  Update in progress for Bs J/ψ φ analysis


_

BACKUP


The Fit FuncGon (for completeness)


2 3 DETAILS

ASL =N++ −N−−

N++ + N−−

L =�

i

�

j

��n(i,j)

ij

e−�ij

n(i, j)!

�

�ij =BBXS · SXS

b(i) · SXS

b(j) + BBXS

FK· Sb(i) · Sb(j)

+�CC + CCXS

FK

�· Sc(i) · Sc(j) + PP XS · Sp(i) · Sp(j)

+1

2

�BP XS · (Sb(i) · Sp(j) + Sp(i) · Sb(j))

+ CP XS · (Sc(i) · Sp(j) + Sp(i) · Sc(j))

+ BCXS · (Sb(i) · Sc(j) + Sc(i) · Sb(j))�

1

2

�(CP − BP )2

CP + BP + (0.14 · BP )2+

(BC − 0.046 · BB)2

BC + (0.046)2 · BB + (0.013 · BB)2

�

CP LS = (1.05 ± 0.05) · CP OS CP ++ = (1.2 ± 0.1) · CP −−

BP LS = (0.87 ± 0.07) · BP OS BP ++ = (1.15 ± 0.05) · BP −−

BCLS = BCOS BC++ = BC−−

2 General

Here we have the general Text

3 Details

And here are the details

3.1 A nice graph

Fig. 1 shows a nice graph.

3.2 URLs

This is a link to the CDF home page. And this is a link to Spires:

And this one goes to a CDF note:

CDF Note 5981.

Fit Results


|A0|2 = 0.348±0.041 (stat) ± 0.021 (syst) |A|||2 = 0.287±0.043 (stat) ± 0.011 (syst) |Aperp|2 = 0.365±0.044 (stat) ± 0.027 (syst) cosδ|| = -‐0.91+0.15-‐0.13 (stat) ± 0.009 (syst)

fL = 0.348±0.041 (stat) ± 0.021 (syst) fT = 0.652±0.041 (stat) ± 0.021 (syst)

0f0 0.2 0.4 0.6 0.8 1

f0.2

0.4

0.6

0.8

1

CDFII CL=68.3%Beneke et al., NPB 774 (2007)Datta et al., EPJC 60 (2009)Cheng et al., PRD 80 (2009)Ali et al., PRD 65 (2002)

)/20

=(1 - ff

-1CDF Run II Preliminary L = 2.9 fb

CDF Public Note 10064

MeasurementsoftheBsMixing* PhaseatCDFweb.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...

Documents

Transcript of MeasurementsoftheBsMixing* PhaseatCDFweb.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...

Measurements*of*the*Bs*Mixing* Phase*atCDF*web.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...

Documents

Transcript of Measurements*of*the*Bs*Mixing* Phase*atCDF*web.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...

MeasurementsoftheBsMixing* PhaseatCDFweb.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...

Transcript of MeasurementsoftheBsMixing* PhaseatCDFweb.mit.edu/panic11/talks/tuesday/PARALLEL-3I/5... ·...