1
0.63 30.41(3.62 0.22 ) 10
exp LQCDubV
|f(q2)|2
|VCKM|2
HQS
D ( )2 2 2cs(d)2
|V | |f (q )|q
Kd
d
Importance of Charm Semileptonic Decays
Potentially useful input to Vub from exclusive B semileptonic decays
( ) ~ 6% precision
BABAR/Belle/CLEO(HFAG)
Br B l
Assuming theoretical
form factors Vcs and Vcd
Vub
11- 17% e.g. HPQCD &FNAL
(summer 2008)
1
2
3
22( )B
ubf q V
22( )D
cdf q V
l
B
l
B
D
Assuming Vcs and Vcd known, we can check theoretical calculations of the form factors
Related atsame invariant4 velocity
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey
2 2
Expt. 5%
16q GeV
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 2
FNAL-MILC-HPQCDPRL 94, 011601 (2005), and arXiv:0906.2498 [hep-lat].
2
2 2 2 2
(0)( )
1 1pole pole
f qq m
f
q m
Modified pole model used for comparison
2
cs2 33 2 22( ) V
24F
KPGd
f qdq
Form factor measures probability hadron will be formed
0 / Form Factor: test of LQCDD K e
2
0
All tags
integrated over q
14121 121
D K ev
Binned likelihood fits to U distributions are performed in each q2 bin and each tag mode
2 2 2q ( )W e vm P P
2
0
All tags
integrated over q
1372 39
D ev
S/N ~40/1S/N ~300/1
| |missmissU E P ��������������
Shape: experiments compatible with LQCD. Normalization: experiments (1.2% for K-eν and 2.0% for π-eν) consistent with LQCD (10%). LQCD precision lags
arXiv:0906.2983 (accepted PRD Jul 22 2009)
+Normalization: f (0)K+Normalization: f (0)
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 3
CLEO-c: the most precise direct determination of Vcs
|Vcs| & |Vcd| Results
*
CLEO-c: νN remains most precise determination (for now)
N
cd cd( V ) / V ~ 3.1%(expt) 10%(theory)
cs cs( V ) / V ~ 1.1%(expt) 10%(theory)
* PDG2000 Fits use Becher-Hill z-expansion
1(818 pb ) 0.985 0.009 0.006
| |
stat syst theor
0.103
y
csCLEO c V
1(818 pb ) 0.234 0.007 0.0
| |
stat syst t
02 0.0
heor
25
y
cdCLEO c V
arXiv:0906.2983 (accepted PRD Jul 22 2009)
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 4
CLEO-c: the most precise direct determination of Vcs
|Vcs| & |Vcd| Results
*
CLEO-c: νN remains most precise determination (for now)
N
cd cd( V ) / V ~ 3.1%(expt) 10%(theory)
cs cs( V ) / V ~ 1.1%(expt) 10%(theory)
* PDG2000
1(818 pb ) 0.985 0.009 0.006
| |
stat syst theor
0.103
y
csCLEO c V
1(818 pb ) 0.234 0.007 0.0
| |
stat syst t
02 0.0
heor
25
y
cdCLEO c V
THEORY UNCERTAINITY REMOVED
arXiv:0906.2983 (accepted PRD Jul 22 2009)
LQCD form factors with improved precision are eagerly awaited
CLEO-c Now
CLEO-c full dataset + 3-4% theoryuncertainties
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 5
cd cs
cd cd
cs cs
V & V direct
(D semileptonic decays CLEO)
CLEO-c full data set
( V ) / V ~ 3.1% theory
( V ) / V ~1.1% theory
D semileptonic decays with comparable theory and experimental uncertaintymay lead to interesting competition between direct and indirect constraints We eagerly await new precise lattice calculations
Plots by Sebastien Descortes-Genon & Ian ShipseySee also talk by Descotres-Genon at joint BABAR-Belle-BESIII-CLEO-c Workshop 11/07, Beijing
Unitarity Test: Compatibility of charm & beauty sectors of CKM matrix?
cd cs
ud cs cd us
V & V indirect
1)K & nucleon
V V & V V
2) Bphysics
Indirect= global CKM fit = 1+2
arXiv:0906.2983 (accepted PRD Jul 22 2009)
+
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 6
Simultaneous fit to D+ 0e , D0 -eRv = 1.40 0.25 0.03R2 = 0.57 0.18 0.06
Form Factors in D → ρeν
q2
cos
cos e
Line is projection for fitted RV, R2
Fix
ed b
ack
gro
und sh
ape a
nd sig
nal ta
ils from
M
C
B(D0 -e+)= (1.560.160.09)10-3
B(D+ 0e+)= (2.320.200.12) 10-3
Isospin average:(D0 -e+) = (0.410.030.02)10-2 ps-1
281pb-1
281pb-1
D+
D0
22
2* 2
( ) /
( ) /ub
cb
Vd B e dq
d B K dq V
r n+ -
G ®µ
G ® l l
Interest: 1st measurement of FF in Cabibbosuppressed charm P V decays +
*Need ,
FF
D
D
K e
er n
n
®
®
PRELIMINARY
Grinstein & Pirjol [hep-ph/0404250]
Update to full data set soon
| |missmissU E c P ��������������
| |missmissU E c P ��������������
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 7
Explanations of the plots
8
2
0
All tags
integrated over q
14121 121
D K ev
2
0
All tags
integrated over q
1372 39
D ev
S/N ~40/1S/N ~300/1
0 0
2
0
0
Fits to distributions for (left) and (right)
with all tag modes and bins combined.
Points are data. Histograms are fit results.
For , the two major background sources are
U D K e D e
q
D e
D
0 0
0
, which peaks at U~0.13 GeV and
, which peaks at U~0.19 GeV
(K is misidentified as e , the is missing.
The charges are not required to match the tag side,
to accomodate doubly-Cabibbo
K e
D K
-suppressed decays.)
See Figs. 2 and 3 in paper 2 for other details on background components.
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 9
Comparisons of form factor normalization parameter f (0)
between CLEO-c and LQCD.
Note that the LQCD results are obtained using the modified pole model,
while the CLEO results are obtained using the 3-p
arameter
Becher-Hill series parametrization.
The LQCD results are from
FNAL MILC HPQCD
[PRL 94,011601 2005 and arXiv : 0906.2498 [hep lat]]
+Normalization: f (0)K+Normalization: f (0)
10
FNAL-MILC-HPQCDPRL 94, 011601 (2005), and arXiv:0906.2498 [hep-lat].
Modified pole model used for comparison
2f(q ) comparisons between isospin conjugate modes
and with LQCD calculations.
The solid lines represent LQCD fits to the modified pole model.
The LQCD results are from
FNAL MILC HPQCD
[PRL 94,011601 2
005 and arXiv : 0906.2498 [hep lat]]
The inner bands show LQCD statistical uncertainties,
and the outer bands the sum in quadrature of
LQCD statistical and systematic uncertainties
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 11
*
N
* PDG2000 Fits use Becher-Hill z-expansion
cs cd
cs
Comparisons of determinations of |V | and |V |. For
the determination of |V | with (Kl ) we use PDG2000,
as PDG 2002 and 2004 do not quote a value
from this technique and
subsequent PDG determinatio
ns include
a result obtained from an earlier
CLEO-c measurement.
The f(0)|V | values are obtained from fits using
the Becher-Hill z-expansion.cx
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 12
*
N
* PDG2000
THEORY UNCERTAINITY REMOVED
The same plots as on last page,
but with the theory (LQCD) uncertainties removed.
These are plots are used to overlay with the
plots on the last slide,
to make the point that our uncertainties are
dominated by uncertainties from LQCD.
CLEO-c Now
CLEO-c full dataset + 3-4% theoryuncertainties
DPF Jul 30 2009 Charm Semileptonic Ian Shipsey 13
Plots by Sebastien Descortes-Genon & Ian ShipseySee also talk by Descotres-Genon at joint BABAR-Belle-BESIII-CLEO-c Workshop 11/07, Beijing
arXiv:0906.2983 (accepted PRD Jul 22 2009)
+These plots were made by Sebastien Descortes-Genon and Ian Shipsey.In this |Vcs| vs. |Vcd| 2D plane,light blue shows the 95% C.L. limit set by indirect determinations from Kaon and neutrino experiments.Green shows the limit set by indirect determinations from B physics. The yellow area is obtained by combining the indirect determinations.The cross shows the central values determined using the CLEO-c full dataset, with the orange ellipse showing the current 95% C.L. limit set by CLEO-c and red ellipse showing the limit if theory uncertainties can be reduced to 3-4%. The CLEO-c analysis is a direct determination.
14
Fix
ed b
ack
gro
und sh
ape a
nd sig
nal ta
ils from
M
C
281pb-1
281pb-1
D+
D0| |missmissU E c P ��������������
| |missmissU E c P ��������������
0 0
*0 0
0 * 0
Fits to distributions in the data for
(top) and (bottom).
The background peaks in the positive U regions
are primarily due to
(for ) and
(for ).
U
D e D e
D K e D e
D K e D e
15
q2
cos
cos e
Line is projection for fitted RV, R2
2
Projections of the data and
the simultaneous fits to isospin conjugate modes
onto q (4-momentum squared of the e pair),
cos (the angle between in the rest frame
and the in the D rest frame),
co
es (the angle between the e in the W rest frame
and the W in the D rest frame)
and (the acoplanarity angle between the planes
of the and the W).
Dots with error bars are the data,
the solid lines ar
e the fits,
and the dashed line shows background contributions.