We measure the primary lepton momentum spectrum in $\overline{B}\ensuremath{\rightarrow}X\mathcal{l}\overline{\ensuremath{\nu}}$ decays, for ${p}_{\mathcal{l}}>~1.5\mathrm{GeV}/c$ in the B rest frame. From this, we calculate various moments of the spectrum. In particular, we find ${R}_{0}\ensuremath{\equiv}{\ensuremath{\int}}_{1.7\mathrm{GeV}}(d\ensuremath{\Gamma}{/dE}_{\mathrm{sl}}{)dE}_{\mathcal{l}}/{\ensuremath{\int}}_{1.5\mathrm{GeV}}(d\ensuremath{\Gamma}{/dE}_{\mathrm{sl}}{)dE}_{\mathcal{l}}=0.6187\ifmmode\pm\else\textpm\fi{}{0.0014}_{\mathrm{stat}}\ifmmode\pm\else\textpm\fi{}{0.0016}_{\mathrm{sys}}$ and ${R}_{1}\ensuremath{\equiv}{\ensuremath{\int}}_{1.5\mathrm{GeV}}{E}_{\mathcal{l}}(d\ensuremath{\Gamma}{/dE}_{\mathrm{sl}}{)dE}_{\mathcal{l}}/{\ensuremath{\int}}_{1.5\mathrm{GeV}}(d\ensuremath{\Gamma}{/dE}_{\mathrm{sl}}{)dE}_{\mathcal{l}}=(1.7810\ifmmode\pm\else\textpm\fi{}{0.0007}_{\mathrm{stat}}\ifmmode\pm\else\textpm\fi{}{0.0009}_{\mathrm{sys}})\mathrm{GeV}.$ We use these moments to determine non-perturbative parameters governing the semileptonic width. In particular, we extract the heavy quark expansion parameters $\overline{\ensuremath{\Lambda}}=(0.39\ifmmode\pm\else\textpm\fi{}{0.03}_{\mathrm{stat}}\ifmmode\pm\else\textpm\fi{}{0.06}_{\mathrm{sys}}\ifmmode\pm\else\textpm\fi{}{0.12}_{\mathrm{th}})\mathrm{GeV}$ and ${\ensuremath{\lambda}}_{1}=(\ensuremath{-}0.25\ifmmode\pm\else\textpm\fi{}{0.02}_{\mathrm{stat}}\ifmmode\pm\else\textpm\fi{}{0.05}_{\mathrm{sys}}\ifmmode\pm\else\textpm\fi{}{0.14}_{\mathrm{th}}){\mathrm{GeV}}^{2}.$ The theoretical constraints used are evaluated through order ${1/M}_{B}^{3}$ in the non-perturbative expansion and ${\ensuremath{\beta}}_{0}{\ensuremath{\alpha}}_{s}^{2}$ in the perturbative expansion. We use these parameters to extract $|{V}_{\mathrm{cb}}|$ from the world average of the semileptonic width and find $|{V}_{\mathrm{cb}}|=(40.8\ifmmode\pm\else\textpm\fi{}{0.5}_{{\ensuremath{\Gamma}}_{\mathrm{sl}}}\ifmmode\pm\else\textpm\fi{}{0.4}_{({\ensuremath{\lambda}}_{1},\overline{\ensuremath{\Lambda}}{)}_{\mathrm{exp}}}\ifmmode\pm\else\textpm\fi{}{0.9}_{\mathrm{th}})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}.$ In addition, we extract the short range b-quark mass ${m}_{b}^{1\mathrm{S}}=(4.82\ifmmode\pm\else\textpm\fi{}{0.07}_{\mathrm{exp}}\ifmmode\pm\else\textpm\fi{}{0.11}_{\mathrm{th}})\mathrm{GeV}{/c}^{2}.$ Finally, we discuss the implications of our measurements for the theoretical understanding of inclusive semileptonic processes.

10.1103/physrevd.67.072001

Cite

Citations (18)

Flavor-Specific InclusiveBDecays to Charm

Physical Review Letters (1998)

T. E. Coan V. Fadeyev I. Korolkov Y. Maravin I. Narsky

We have measured the branching fractions for B -> D_bar X, B -> D X, and B -> D_bar X \ell^+ \nu, where ``B'' is an average over B^0 and B^+, ``D'' is a sum over D^0 and D^+, and``D_bar'' is a sum over D^0_bar and D^-. From these results and some previously measured branching fractions, we obtain Br(b -> c c_bar s) = (21.9 $\pm$ 3.7)%, Br(b -> s g) < 6.8% @ 90% c.l, and Br(D^0 -> K^- \pi^+) = (3.69 $\pm$ 0.20)%. Implications for the ``B semileptonic decay problem'' (measured branching fraction being below theoretical expectations) are discussed. The increase in the value of Br(b -> c c_bar s) due to $B -> D X$ eliminates 40% of the discrepancy.

Bar (unit)

Branching fraction

Branching (polymer chemistry)

10.1103/physrevlett.80.1150

Cite

Citations (60)

Study of the Semileptonic Charm DecaysD0→π−ℓ+νandD0→

Physical Review Letters (2005)

G. S. Huang D. H. Miller V. Pavlunin B. Sanghi E. I. Shibata

We investigate the decays D(0)-->pi(-)l(+)nu and D(0)-->K(-)l(+)nu, where l is e or mu, using approximately 7 fb(-1) of data collected with the CLEO III detector. We find R(0) identical with B(D(0)-->pi(-)e(+)nu)/B(D(0)-->K(-)e(+)nu)=0.082+/-0.006+/-0.005. Fits to the kinematic distributions of the data provide parameters describing the form factor of each mode. Combining the form factor results and R(0) gives |f(pi)(+)(0)|(2)|V(cd)|(2)/|f(K)(+)(0)|(2)|V(cs)|(2)=0.038(+0.006+0.005)(-0.007-0.003).

Charm (quantum number)

Semileptonic decay

10.1103/physrevlett.94.011802

Cite

Citations (46)

Search for the Decayϒ(1S)→γη′

Physical Review Letters (2001)

S. J. Richichi H. Severini P. Skubic S. Dytman V. Savinov

We report on a search for the radiative decay Upsilon(1S)-->gammaeta(') in 61.3 pb(-1) of data taken with the CLEO II detector at the Cornell Electron Storage Ring. Three decay chains were investigated, all involving eta(')-->pi(+)pi(-)eta, followed by eta-->gammagamma, eta-->pi(0)pi(0)pi(0), or eta-->pi(+)pi(-)pi(0). We find no candidate events in any of the three cases and set a combined upper limit of 1.6x10(-5) at 90% C.L., significantly smaller than the previous limit. We compare our result to other radiative Upsilon decays, to radiative J/psi decays, and to theoretical predictions.

10.1103/physrevlett.87.141801

Cite

Citations (7)

Erratum: Experimental tests of lepton universality in τ decay [Phys. Rev. D 55, 2559 (1997)]

Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields (1998)

A. Anastassov S. Blinov J. E. Duboscq K. D. Fisher D. Fujino

The originally published correlation coefficients between measured branching ratios are incorrect.

10.1103/physrevd.58.119903

Cite

Citations (3)

Search for neutrinoless [Formula presented] decays: [Formula presented] and [Formula presented]

Lincoln (University of Nebraska) (1997)

K. W. Edwards A. Bellerive R. Janicek D. B. MacFarlane K. W. McLean

Source

Cite

Citations (0)

Study of two photon transistions in CLEO-III Upsilon (3S) data

Contributed to (2002)

D. Cinabro D. L. Hartill C. J. Stepaniak H. Kagan H. Schwarthoff

Source

Cite

Citations (0)

Study of the Decayτ−→2π−π

Physical Review Letters (1997)

S. Anderson Y. Kubota S. J. Lee J. J. O’Neill S. Patton

The decay ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}2{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}3{\ensuremath{\pi}}^{0}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ has been studied with the CLEO II detector at the Cornell Electron Storage Ring. The branching fraction is measured to be $(2.85\ifmmode\pm\else\textpm\fi{}0.56\ifmmode\pm\else\textpm\fi{}0.51)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$. The result is in good agreement with the isospin expectation but somewhat below the conserved-vector-current prediction. We have searched for resonance substructure in the decay. Within the statistical precision, the decay is saturated by the channels ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}2{\ensuremath{\pi}}^{0}\ensuremath{\omega}{\ensuremath{\nu}}_{\ensuremath{\tau}}$, $2{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}\ensuremath{\eta}{\ensuremath{\nu}}_{\ensuremath{\tau}}$, and ${\ensuremath{\pi}}^{\ensuremath{-}}2{\ensuremath{\pi}}^{0}\ensuremath{\eta}{\ensuremath{\nu}}_{\ensuremath{\tau}}$. This is the first observation of this \ensuremath{\omega} decay mode and the branching fraction is measured to be $({1.89}_{\ensuremath{-}0.67}^{+0.74}\ifmmode\pm\else\textpm\fi{}0.40)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$.

10.1103/physrevlett.79.3814

Cite

Citations (10)

Observation of ExclusiveBDecays to Final States Containing a Charmed Baryon

Physical Review Letters (1997)

X. Fu B. Nemati S. J. Richichi W. R. Ross P. Skubic

Using data collected in the region of the Υ(4S) resonance with the CLEO-II detector, we report on the first observation of exclusive decays of the B meson to final states with a charmed baryon. We have measured the branching fractions B(B−→Λ+c¯pπ−)=(0.62+0.23−0.20±0.11±0.10)×10−3 and B(¯B0→Λ+c¯pπ+π−)=(1.33+0.46−0.42±0.31±0.21)×10−3, where the first error is statistical, the second is systematic, and the third is due to uncertainty in the Λ+c branching fractions. In addition, we report upper limits for final states of the form ¯B→Λ+c¯p(nπ) and Λ+c¯p(nπ)π0, where (nπ) denotes up to four charged pions.Received 12 July 1996DOI:https://doi.org/10.1103/PhysRevLett.79.3125©1997 American Physical Society

Branching (polymer chemistry)

Branching fraction

Electron–positron annihilation

10.1103/physrevlett.79.3125

Cite

Citations (24)

Search forB→τνandB→Kνν

Physical Review Letters (2001)

T. E. Browder Y. Li J. L. Rodriguez H. Yamamoto T. Bergfeld

We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level.

10.1103/physrevlett.86.2950

Cite

Citations (22)