Phys. Rev. D 107, 032003 (2023) We report a study of $\Lambda_c^+ \to \Sigma^+ \pi^0$, $\Lambda_c^+ \to
\Sigma^+ \eta$, and $\Lambda_c^+ \to \Sigma^+ \eta'$ using the data sample
corresponding to an ...integrated luminosity of 980 $\rm fb^{-1}$ collected with
the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The
branching fractions relative to $\Lambda_c^+ \to \Sigma^+ \pi^0$ are measured
as: $\mathcal{B}_{\Lambda_c^+ \to \Sigma^+ \eta}/\mathcal{B}_{\Lambda_c^+ \to
\Sigma^+ \pi^0}=0.25 \pm 0.03 \pm 0.01$ and $\mathcal{B}_{\Lambda_c^+ \to
\Sigma^+ \eta'}/\mathcal{B}_{\Lambda_c^+ \to \Sigma^+ \pi^0}=0.33 \pm 0.06 \pm
0.02$. Using $\mathcal{B}_{\Lambda_c^+ \to \Sigma^+ \pi^0}=(1.25 \pm 0.10)\%$,
we obtain $\mathcal{B}_{\Lambda_c^+ \to \Sigma^+ \eta}=(3.14 \pm 0.35 \pm 0.11
\pm 0.25)\times10^{-3}$ and $\mathcal{B}_{\Lambda_c^+ \to \Sigma^+ \eta'}=(4.16
\pm 0.75 \pm 0.21 \pm 0.33)\times10^{-3}$. Here the uncertainties are
statistical, systematic, and from $\mathcal{B}_{\Lambda_c^+ \to \Sigma^+
\pi^0}$, respectively. The ratio of the branching fraction of $\Lambda_c^+ \to
\Sigma^+ \eta'$ with respect to that of $\Lambda_c^+ \to \Sigma^+ \eta$ is
measured to be $\mathcal{B}_{\Lambda_c^+ \to \Sigma^+
\eta'}/\mathcal{B}_{\Lambda_c^+ \to \Sigma^+ \eta}=1.34 \pm 0.28 \pm 0.06$. We
update the asymmetry parameter of $\Lambda_c^+ \to \Sigma^+ \pi^0$,
$\alpha_{\Sigma^+ \pi^0} = -0.48 \pm 0.02 \pm 0.02$, with a considerably
improved precision. The asymmetry parameters of $\Lambda_c^+ \to \Sigma^+ \eta$
and $\Lambda_c^+ \to \Sigma^+ \eta'$ are measured to be $\alpha_{\Sigma^+ \eta}
= -0.99 \pm 0.03 \pm 0.05$ and $\alpha_{\Sigma^+ \eta'} = -0.46 \pm 0.06 \pm
0.03$ for the first time.
Science Bulletin 68 (2023) 583 We report a study of $\Lambda_c^+\to\Lambda h^+$ and
$\Lambda_c^+\to\Sigma^{0} h^+$ ($h\!=\!K,\,\pi$) decays based on a data sample
of 980~${\rm fb}^{-1}$ collected ...with the Belle detector at the KEKB
energy-asymmetric $e^+e^-$ collider. The first results of direct $C\!P$
asymmetry in two-body singly Cabibbo-suppressed (SCS) decays of charmed baryons
are measured, $A_{C\!P}^{\rm{dir}}(\Lambda_c^+\to\Lambda
K^+)\!=\!+0.021\pm0.026\pm0.001$ and
$A_{C\!P}^{\rm{dir}}(\Lambda_c^+\to\Sigma^0K^+)\!=\!+0.025\pm0.054\pm0.004$. We
also make the most precise measurement of the decay asymmetry parameters
($\alpha$) for the four modes of interest and search for $C\!P$ violation via
the $\alpha$-induced $C\!P$ asymmetry ($A_{C\!P}^{\alpha}$). We measure
$A_{C\!P}^{\alpha}(\Lambda_c^+\to\Lambda K^+)\!=\!{-0.023\pm0.086\pm0.071}$ and
$A_{C\!P}^{\alpha}(\Lambda_c^+\to\Sigma^0K^+)\!=\!{+0.08\pm 0.35\pm 0.14}$,
which are the first $A_{C\!P}^{\alpha}$ results for SCS decays of charmed
baryons. We search for $\Lambda$-hyperon $C\!P$ violation in
$\Lambda_c^+\to(\Lambda,\,\Sigma^0)\pi^+$ and find
$A_{C\!P}^{\alpha}(\Lambda\to p\pi^{-})\!=\!{+0.013\pm0.007\pm0.011}$. This is
the first time that hyperon $C\!P$ violation has been measured via
Cabibbo-favored charm decays. No evidence of baryon $C\!P$ violation is found.
We also obtain the most precise branching fractions for two SCS $\Lambda_c^+$
decays, $\mathcal{B}(\Lambda_c^+\to\Lambda
K^+)\!=\!(6.57\pm0.17\pm0.11\pm0.35)\times10^{-4}$ and
$\mathcal{B}(\Lambda_c^+\to\Sigma^0K^+)\!=\!(3.58\pm0.19\pm0.06\pm0.19)\times10^{-4}$.
The first uncertainties are statistical and the second systematic, while the
third uncertainties come from the uncertainties on the world average branching
fractions of $\Lambda_c^+\to(\Lambda,\,\Sigma^0)\pi^+$.
We present the analysis of two-particle angular correlations using coordinate
systems defined with the conventional beam axis and the event thrust axis, and
propose the latter to be a useful ...representation for the correlation structure
interpretation in the $e^+ e^-$ collision system. The $e^+ e^-$ collisions to
hadronic final states at center-of-mass energies of $\sqrt{s} = 10.52$ GeV and
$10.58$ GeV are recorded by the Belle detector at KEKB. In this paper, results
on the first dataset are supplementary to the previous Belle publication
arXiv:2201.01694 while the latter one is the first two-particle correlation
measurement at a collision energy on the $\Upsilon(4S)$ resonance and sensitive
to its decay products. Measurements are reported as a function of the
charged-particle multiplicity. Finally, a qualitative understanding of the
correlation structure is discussed using a combination of Monte Carlo
simulations and experimental data.
Based on a data sample of 983 fb$^{-1}$ collected with the Belle detector at
the KEKB asymmetric-energy $e^+e^-$ collider, we present the study of the
heavy-flavor-conserving decay $\Xi_{c}^{0}\to ...\Lambda_{c}^{+}\pi^{-}$ with
$\Lambda_{c}^{+}$ reconstructed via its $pK^{-} \pi^{+}$ decay mode. The
branching fraction ratio $\mathcal{B}(\Xi_{c}^{0}\to
\Lambda_{c}^{+}\pi^{-})/\mathcal{B}(\Xi_{c}^{0}\to \Xi^{-}\pi^{+})$ is measured
to be $0.38 \pm 0.04 \pm 0.04$. Combing with the world average value of
$\mathcal{B}(\Xi_{c}^{0}\to \Xi^{-}\pi^{+})$, the branching fraction
$\mathcal{B}(\Xi_{c}^{0}\to \Lambda_{c}^{+}\pi^{-})$ is deduced to be $(0.54
\pm 0.05 \pm 0.05 \pm 0.12)\%$. Here, the uncertainties above are statistical,
systematic, and from $\mathcal{B}(\Xi_c^{0} \to \Xi^{-}\pi^{+})$, respectively.
Phys. Rev. D 107, 032001 (2023) We present the first search for the weak radiative decays $\Lambda_c^+ \to
\Sigma^+ \gamma$ and $\Xi_c^0 \to \Xi^0 \gamma$ using a data sample of
980~fb$^{-1}$ ...collected by the Belle detector operating at the KEKB
asymmetric-energy $e^+e^-$ collider. There are no evident $\Lambda_c^+ \to
\Sigma^+ \gamma$ or $\Xi_c^0 \to \Xi^0 \gamma$ signals. Taking the decays
$\Lambda_c^+ \to p K^- \pi^+$ and $\Xi_c^0 \to \Xi^- \pi^+$ as normalization
channels, the upper limits at 90\% credibility level on the ratios of branching
fractions ${\cal B}(\Lambda_c^+ \to \Sigma^+ \gamma)/{\cal B}(\Lambda_c^+ \to p
K^{-} \pi^+) < 4.0 \times 10^{-3}$ and ${\cal B}(\Xi_c^0 \to \Xi^0
\gamma)/{\cal B}(\Xi_c^0 \to \Xi^- \pi^+) < 1.2 \times 10^{-2}$ are determined.
We obtain the upper limits at 90\% credibility level on the absolute branching
fractions ${\cal B}(\Lambda_c^+ \to \Sigma^+ \gamma) < 2.6 \times 10^{-4}$ and
${\cal B}(\Xi_c^0 \to \Xi^0 \gamma) < 1.8 \times 10^{-4}$.
We report the first measurement of the \(Q^2\) distribution of \(X(3915)\) produced by single-tag two-photon interactions. The decay mode used is \(X(3915) \rightarrow J/\psi\omega\). The covered ...\(Q^2\) region is from 1.5 (GeV/\(c\))\(^2\) to 10.0 (GeV/\(c\))\(^2\). We observe \(7.9\pm 3.1({\rm stat.})\pm 1.5({\rm syst.})\) events, where we expect \(4.1\pm 0.7\) events based on the \(Q^2=0\) result from the no-tag two-photon process, extrapolated to higher \(Q^2\) region using the \(c\bar{c}\) model of Schuler, Berends, and van Gulik. The shape of the distribution is also consistent with this model; we note that statistical uncertainties are large.
The aim of the study was to determine the frequency of the metabolic syndrome in a specific group of people.
The ATP III criteria were used to identify the metabolic syndrome in a group of 1,410 ...corporate executives belonging to a specialist health and fitness company in South Africa.
Using three criteria as specified by the ATP III panel, 31% of this group of corporate executives fulfilled the criteria for the diagnosis of the metabolic syndrome. In a small subset of black executives, a similar finding was obtained. Another one-third of the executives had two criteria of the metabolic syndrome.
The metabolic syndrome was common in a group of corporate executives.
We present a search for the baryon number \(B\) and lepton number \(L\) violating decays \(\tau^- \rightarrow \Lambda \pi^-\) and \(\tau^- \rightarrow \bar{\Lambda} \pi^-\) produced from the ...\(e^+e^-\to \tau^+\tau^-\) process, using a 364 fb\(^{-1}\) data sample collected by the Belle~II experiment at the SuperKEKB collider. No evidence of signal is found in either decay mode, which have \(|\Delta(B-L)|\) equal to \(2\) and \(0\), respectively. Upper limits at 90\% credibility level on the branching fractions of \(\tau^- \rightarrow \Lambda\pi^-\) and \(\tau^- \rightarrow \bar{\Lambda}\pi^-\) are determined to be \(4.7 \times 10^{-8}\) and \(4.3 \times 10^{-8}\), respectively.
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