1,010 research outputs found
Measurement of Orbitally Excited D-Mesons at CDF II
Measurement of Orbitally Excited D-Mesons at CDF II Igor V. Gorelov (For the
CDF Collaboration)
Talk given on behalf of the CDF Collaboration at the First Meeting of the APS
Topical Group on Hadronic Physics, GHP 2004, 24-26 October 2004, FERMILAB.
Results on the first measurement of orbitally excited neutral D-meson states,
D*_2 and D_1, produced in hadron collisions at Tevatron are presented. Using
data from the displaced track trigger, CDF II collects the largest world sample
of these states in decay modes D*+ pi-, D+ pi-. Masses and widths of both
states have been measured with precision better than or comparable to the world
average.Comment: 6 pages, 5 figures, talk given on behalf of the CDF Collaboration at
the First Meeting of the APS Topical Group on Hadronic Physics, GHP 2004, Oct
24-26,2004, Fermilab, Batavia, Illinoi
Indications for Factorization and from Rare B Decay Data
Surveying known hadronic rare B decays, we find that the factorization
approximation can give a coherent account of , and
data and give predictions for , and modes,
{\it if is taken as negative} (in standard phase convention)
rather than positive. As further confirmation, we expect a lower
value at B Factories as compared to current fits, and mixing close to LEP
bounds at SLD and CDF.Comment: 11 pages, revtex, 4 figures (unchanged and eps files included);
version (including title and abstract change) to appear in Phys. Rev. Let
Phenomenological Study of Strong Decays of Heavy Hadrons in Heavy Quark Effective Theory
The application of the tensor formalism of the heavy quark effective theory
(HQET) at leading order to strong decays of heavy hadrons is presented.
Comparisons between experimental and theoretical predictions of ratios of decay
rates for B mesons, D mesons and kaons are given. The application of HQET to
strange mesons presents some encouraging results. The spin-flavor symmetry is
used to predict some decay rates that have not yet been measured.Comment: 10 page
CP-Violating Asymmetries in Charmless Non-Leptonic Decays in the Factorization Approach
We present estimates of the direct (in decay amplitudes) and indirect
(mixing- induced) CP-violating asymmetries in the non-leptonic charmless
two-body decay rates for , and decays and their
charged conjugates, where P(V) is a light pseudoscalar (vector) meson. These
estimates are based on a generalized factorization approach making use of
next-to-leading order perturbative QCD contributions which generate the
required strong phases. No soft final state interactions are included. We study
the dependence of the asymmetries on a number of input parameters and show that
there are at least two (possibly three) classes of decays in which the
asymmetries are parametrically stable in this approach. The decay modes of
particular interest are: \optbar{B^0} \to \pi^+ \pi^-, \optbar{B^0} \to
K_S^0 \pi^0, \optbar{B^0} \to K_S^0 \eta^\prime, \optbar{B^0} \to K_S^0
\eta and \optbar{B^0} \to \rho^+ \rho^-. Likewise, the CP-violating
asymmetry in the decays \optbar{B^0} \to K_S^0 h^0 with is found to be parametrically stable and large. Measurements
of these asymmetries will lead to a determination of the phases
and and we work out the relationships in these modes in the
present theoretical framework. We also show the extent of the so-called
"penguin pollution" in the rate asymmetry and of the
"tree shadow" in the asymmetry which will effect the
determination of and from the respective
measurements. CP-violating asymmetries in ,
, and are potentially interesting and are studied here.Comment: 42 pages (LaTex) including 19 figures, requires epsfig.sty; submitted
to Phys. Rev.
Extracting information on CKM phases, electro-weak penguins and new physics from B --> VV decays
We derive constraints for modes ($V= vector meson) that allow
aquantitative assessment of the contributions from electroweak penguins (EWP)
and/or new physics. Interplay of direct CP with oscillation studies then leads
to the extraction of the angles alpha and gamma, using B--> K* omega rho and
B--> rho omega (phi) respectively, if by using our constraint equations it can
be experimentally demonstrated that color-suppressed EWP are small.Comment: 12 pages, 0 figures; revised and expande
Observation of the Dynamic Beta Effect at CESR with CLEO
Using the silicon strip detector of the CLEO experiment operating at the
Cornell Electron-positron Storage Ring (CESR), we have observed that the
horizontal size of the luminous region decreases in the presence of the
beam-beam interaction from what is expected without the beam-beam interaction.
The dependence on the bunch current agrees with the prediction of the dynamic
beta effect. This is the first direct observation of the effect.Comment: 9 page uuencoded postscript file, postscritp file also available
through http://w4.lns.cornell.edu/public/CLNS, submitted to Phys. Rev.
Final-State Phases in Charmed Meson Two-Body Nonleptonic Decays
Observed decay rates indicate large phase differences among the amplitudes
for the charge states in and but
relatively real amplitudes in the charge states for . This
feature is traced using an SU(3) flavor analysis to a sign flip in the
contribution of one of the amplitudes contributing to the latter processes in
comparison with its contribution to the other two sets. This amplitude may be
regarded as an effect of rescattering and is found to be of magnitude
comparable to others contributing to charmed particle two-body nonleptonic
decays.Comment: 19 pages, latex, 4 figures, to be submitted to Phys. Rev.
Observation of the Isospin-Violating Decay
Using data collected with the CLEO~II detector, we have observed the
isospin-violating decay . The decay rate for this mode,
relative to the dominant radiative decay, is found to be .Comment: 8 page uuencoded postscript file, also available through
http://w4.lns.cornell.edu/public/CLN
Observation of a New Charmed Strange Meson
Using the CLEO-II detector, we have obtained evidence for a new meson
decaying to . Its mass is
{}~MeV/ and its width is ~MeV/. Although we do not
establish its spin and parity, the new meson is consistent with predictions for
an , , charmed strange state.Comment: 9 pages uuencoded compressed postscript (process with uudecode then
gunzip). hardcopies with figures can be obtained by sending mail to:
[email protected]
Nonresonant Three-body Decays of D and B Mesons
Nonresonant three-body decays of D and B mesons are studied. It is pointed
out that if heavy meson chiral perturbation theory (HMChPT) is applied to the
heavy-light strong and weak vertices and assumed to be valid over the whole
kinematic region, then the predicted decay rates for nonresonant charmless
3-body B decays will be too large and especially B^- --> pi^- K^+ K^- greatly
exceeds the current experimental limit. This can be understood as chiral
symmetry has been applied there twice beyond its region of validity. If HMChPT
is applied only to the strong vertex and the weak transition is accounted for
by the form factors, the dominant B^* pole contribution to the tree-dominated
direct three-body B decays will become small and the branching ratio will be of
order 10^{-6}. The decay modes B^- --> (K^- h^+ h^-)_{NR} and bar{B}^0 -->
(bar{K}^0 h^+h^-)_{NR} for h = pi, K are penguin dominated. We apply HMChPT in
two different cases to study the direct 3-body D decays and compare the results
with experiment. Theoretical uncertainties are discussed.Comment: 24 pages, 2 figures. New experimental results of direct 3-body D
decays as Reported at ICHEP2002 are included. To appear in Phys. Re
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