141 research outputs found
Application of Many-Body Rayleigh-Schrodinger Perturbation Theory to Excitations Accompanying Photoionization in Molecules
Excitations accompanying photoionizations in molecules (shake-
up processes) are studied on the basis of degenerate many-body
Rayleigh-Schr6dinger perturbation theory (MB - RSPT).
These excitations give rise to satellite lines accompanyin ionization
lines. Decomposition of correlation effects in these processes
into those corresponding to single-particle excitation and single-
particle ionization is discussed
Search for decays to invisible final states at Belle
We report a search for decays into invisible final states using a
data sample of pairs collected at the
resonance with the Belle detector at the KEKB
collider. The signal is identified by fully reconstructing a hadronic decay of
the accompanying meson and requiring no other particles in the event. No
significant signal is observed, and we obtain an upper limit of at the 90% confidence level for the branching fraction of invisible
decay.Comment: 6 pages, 5 figures (9 figure files
Angular analysis of
We present a measurement of angular observables, , , ,
, in the decay , where
is either or . The analysis is performed on
a data sample corresponding to an integrated luminosity of
containing pairs, collected
at the resonance with the Belle detector at the
asymmetric-energy collider KEKB. Four angular observables,
are extracted in five bins of the invariant mass squared of the
lepton system, . We compare our results for with Standard
Model predictions including the region in which the LHCb collaboration
reported the so-called anomaly.Comment: Conference paper for LHC Ski 2016. SM prediction for
corrected and reference for arXiv:1207.2753 adde
Search for B -> phi pi decays
We report on a search for the charmless decays and
that are strongly suppressed in the Standard Model. The
analysis is based on a data sample of pairs
collected at the resonance with the Belle detector at the KEKB
asymmetric-energy collider. We find no significant signal and set
upper limits of for and for at the 90% confidence level.Comment: submitted to Phys. Rev. D (RC
Observation of decays using the 2019-2022 Belle II data sample
We present a measurement of the branching fractions of four decay modes. The measurement is based on data from
SuperKEKB electron-positron collisions at the resonance
collected with the Belle II detector and corresponding to an integrated
luminosity of . The event yields are extracted from fits
to the distributions of the difference between expected and observed meson
energy to separate signal and background, and are efficiency-corrected as a
function of the invariant mass of the system. We find the branching
fractions to be: where the first uncertainty is statistical and
the second systematic. These results include the first observation of
, , and decays and a significant improvement in the precision
of compared to previous measurements
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