相关论文: Precision measurement of $^{\mathbf{210}}$Bi $\bet…
Here we present the specifications of the newly developed beta-spectrometer based on thick full absorption Si(Li) detector. The spectrometer can be used for precision measurements of various beta-spectra, namely for the beta-spectrum shape…
The ASPECT-BET (An sdd-SPECTrometer for BETa decay studies) project aims to develop a novel technique for the precise measurement of forbidden $\beta$ spectra in the 10 keV - 1 MeV range. This technique uses a Silicon Drift Detector (SDD)…
We study the reaction e+e- --> e+e-pi0 and measure the gamma gamma* --> pi0 transition form factor in the momentum transfer range from 4 to 40 GeV^2. The analysis is based on 442 fb^-1 of integrated luminosity collected at PEP-II with the…
We present a description of the originally developed $\beta$-spectrometer consisting of two Si(Li)-detectors with sensitive area thickness above 8~mm and $4\pi$-geometry. The full absorption spectrometer allows for direct measurements of…
Beta decay is a fundamental process that governs nuclear stability and serves as a sensitive probe of the weak interaction and possible physics beyond the Standard Model of particle physics. However, precise measurements of complete $\beta$…
Spectrum shape measurements in nuclear $\beta$ decay can be used to test physics beyond the Standard Model with results being complementary to high-energy collider experiments. In particular, Beyond Standard Model sensitivity of the weak…
We report on a comparison between the theoretically predicted and experimentally measured spectra of the first-forbidden non-unique $\beta$-decay transition $^{137}\textrm{Xe}(7/2^-)\to\,^{137}\textrm{Cs}(7/2^+)$. The experimental data were…
We present a new calculation of the B->pi form-factor f_+, relevant for the measurement of |V_{ub}| from semileptonic B->pi transitions, from QCD sum rules on the light-cone. The new element is the calculation of radiative corrections to…
The electron spectra of the $\beta$ decays of $^{92}$Rb and $^{142}$Cs, key contributors to the reactor antineutrino spectrum, were measured at the IGISOL facility using radioactive beams of high isotopic purity. The shapes of the measured…
A measurement of the vector to pseudoscalar conversion decay $\phi \to \pi^0 e^+e^-$ with the KLOE experiment is presented. A sample of $\sim 9500$ signal events was selected from a data set of 1.7 fb$^{-1}$ of $e^+e^-$ collisions at…
The exclusive process $e^+e^-\rightarrow\Lambda\bar{\Lambda}$, with $\Lambda \to p\pi^-$ and $\bar{\Lambda} \to \bar{p}\pi^+$, has been studied at $\sqrt{s} =$ 2.396 GeV for measurement of the $\Lambda$ electric and magnetic form factors,…
Based on a sample of $(1.0087\pm0.0044)\times10^{10}$ $J/\psi$ events collected at BESIII, the transition form factor of the $\eta$ meson is extracted by analyzing $J/\psi\to\gamma\eta',~\eta'\to\pi^+\pi^-\eta,~\eta\to\gamma l^+l^-$…
A sample of 7253 $K^\pm\to\pi^\pm e^+e^-(\gamma)$ decay candidates with 1.0% background contamination has been collected by the NA48/2 experiment at the CERN SPS, allowing a precise measurement of the decay properties. The branching ratio…
The $^{144}$Ce -- $^{144}$Pr electron antineutrino source is one of the most suitable radiochemical sources for experiments searching for the oscillations of active neutrinos to the light sterile state. In the current work the…
Highly precise measurements of the $^{99}$Tc beta spectrum were performed in two laboratories using metallic magnetic calorimeters. Independent sample preparations, evaluation methods and analyses yield consistent results and the spectrum…
A new instrument for spot profile analysis of electron diffraction - SPA-LEED - has been set up. The instrument works either with a transparent phosphor screen for visual inspection of the pattern or in its main mode with a channeltron for…
The low $Q^2$ slopes of the the transition form factors provide a unique method to measure the sizes of the neutral pseudo-scalar mesons, since they do not have electromagnetic form factors. From the slope one obtains the "axial transition…
Using the CLEO~II detector, we have measured the differential cross sections for exclusive two-photon production of light pseudoscalar mesons $\pi^0$, $\eta$, and $\eta^{\prime}$. From our measurements we have obtained the form factors…
The Born cross section of the $e^{+}e^{-}~\rightarrow~\Lambda_{c}^{+} \bar{\Lambda}_{c}^{-}$ process is measured with unprecedented precision using data collected with the BESIII detector at $\sqrt{s}=4574.5$, $45580.0$, $4590.0$ and…
High-resolution spectroscopy on the $A^2\Pi$ - $X^2\Sigma^+$ electronic system of $^{138}$Ba$^{19}$F is performed using a cold molecular beam produced by a buffer gas source. The hyperfine structure in both $X^2\Sigma^+$ ground and $A^2\Pi$…