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Considering the mass, parity and \\[D^0 p\\] decay mode, we tentatively assign the \\[\\Lambda _c(2940)\\] as the \\[P-\\]wave states with one radial excitation. Then, via studying the strong decay behavior of the \\[\\Lambda _c(2940)\\] within the \\[^3P_0\\] model, we obtain that the total decay widths of the \\[\\Lambda _{c1}(\\frac{1}{2}^-,2P)\\] and \\[\\Lambda _{c1}(\\frac{3}{2}^-,2P)\\] states are 16.27 and 25.39 MeV, respectively. Compared with the experimental total width \\[27.7^{+8.2}_{-6.0}\\pm 0.9^{+5.2}_{-10.4}~\\mathrm {MeV}\\] measured by LHCb Collaboration, both assignments are allowed, and the \\[J^P=\\frac{3}{2}^-\\] assignment is more favorable. Other \\[\\lambda \\]-mode \\[\\Sigma _c(2P)\\] states are also investigated, which are most likely to be narrow states and have good potential to be observed in future experiments.

We argue that the mass, production, total decay width, and decay pattern of the η2(1870) do not appear to contradict with the picture of it as being the conventional 2 1D2\\(q\\bar{q}\\) state. The possibility of the η2(1870) being a mixture of the conventional \\(q\\bar{q}\\) and a hybrid is also discussed.

Assuming D*sJ(2317) and DsJ(2460) to be the (0+,1+) chiral partners of the regular particles Ds(1968) and D*s(2112), we calculate the semileptonic decays of Bs to Ds(1968), D*s(2112), DsJ*(2317) and DsJ(2460) in terms of the constituent quark meson model. The large branching ratios of the semileptonic decays of Bs to DsJ*(2317) and DsJ(2460) indicate that these two semileptonic decays should be seen in future experiments.

The contributions of the vector leptoquarks to branching ratios of decays are calculated with account of fermion mixing in leptoguark currents of the general type and the corresponding mass limit for the vector leptoquarks resulting from the current data on these decays is obtained and analysed. It is found that the vector leptoquarks with masses mV > 78 TeV are consistent with current data on these decays. The branching ratios of decays at the possible lower mass mV = 78 TeV are presented and the decays are shown to be the most perspective ones for setting the new more stringent mass limits for the vector leptoquarks.

Results of study of the K+ → π0e+νγ decay at OKA setup are presented. 16889 events of this decay have been observed. The branching ratio with cuts E*γ > 10 MeV, 0.6 < cosΘ*eγ < 0.9 is calculated For the asymmetry Aξ we get Aξ = -0.009 ± 0.012(stat.)

We study the ϒ(1 S ) radiative decays to γπ + π - and γK + K - using data recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e + e - collider at center-of-mass energies at the ϒ(2 S ) and ϒ(3 S ) resonances. The ϒ(1 S ) resonance is reconstructed from the decay ϒ( nS ) → π + π - ϒ(1 S ), n = 2, 3.

Dark matter may consist of previously unknown forms of subatomic particles. An unidentified astronomical x-ray emission line has been interpreted as being caused by the decay of a dark matter particle. If this is correct, then dark matter in the halo of the Milky Way Galaxy should produce a faint emission line across the whole sky. Dessert et al. tested this hypothesis using observations by the XMM-Newton (X-ray Multi-Mirror Mission) space telescope. Analyzing blank-sky regions with a total exposure time of about a year, they found no evidence for the predicted line and set upper limits on the decay rate that rule out the previously proposed dark matter interpretation. Science , this issue p. 1465 X-ray observations of the Milky Way’s halo rule out proposed models of dark matter decay. Observations of nearby galaxies and galaxy clusters have reported an unexpected x-ray emission line around 3.5 kilo–electron volts (keV). Proposals to explain this line include decaying dark matter—in particular, that the decay of sterile neutrinos with a mass around 7 keV could match the available data. If this interpretation is correct, the 3.5-keV line should also be emitted by dark matter in the halo of the Milky Way. We used more than 30 megaseconds of XMM-Newton (X-ray Multi-Mirror Mission) blank-sky observations to test this hypothesis, finding no evidence of the 3.5-keV line emission from the Milky Way halo. We set an upper limit on the decay rate of dark matter in this mass range, which is inconsistent with the possibility that the 3.5-keV line originates from dark matter decay.

We report on the preliminary results of an experimental study of the β decay of 16N, aiming to determine the branching ratio of the βα channel with a precision of ≤ 5%.

The Hoyle state in 12C(Ex = 7.654MeV) is characterized by a pronounced 3α cluster configuration. It is involved in the so-called 3α process in stars, that is responsible of 12C nucleosynthesis. We studied the decay path of the Hoyle state by using the 14N(d, α2)12C(7.654) reaction at 10.5MeV incident energy. We found, with a precision higher of a factor 5 than any other previous experiment, an almost total absence of direct decays by-passing the ground state of 8Be. A new upper limit of such a decay width is placed at 0.043% (95% C.L.). Astrophysical 3α process reaction rate calculations have to be consequently revised.

Environmental DNA (eDNA) analysis from water samples is a promising new method to identify both targeted species and whole communities of aquatic organisms. However, the current literature regarding eDNA shedding rates primarily focuses on fish and most decay rate constants are reported for warm sunlit waters. Here, we conducted experiments to investigate how eDNA shedding differs between animal forms and how long eDNA can persist in waters of varying temperature and light conditions. We designed quantitative PCR assays for one fish (mummichog, Fundulus heteroclitus), one crustacean (grass shrimp, Palaemon spp.), and two scyphomedusae (moon jelly, Aurelia aurita and nettle, Chrysaora spp.) to estimate eDNA shedding and decay rates. We found that shedding rates were highly variable for all organisms, but grass shrimp had the lowest shedding rate. We quantified eDNA decay rate constants at 6, 15, and 23°C and found that decay rate constants of mummichog and grass shrimp were larger at higher temperatures, while those of scyphomedusae did not show clear temperature dependence. We also found that higher‐order decay models with tails fit the data better than first‐order log‐linear models, suggesting temporal variability in eDNA decay rates. Results indicate that different animal forms shed different types of eDNA, impacting both shedding and decay rates. These findings fill critical knowledge gaps regarding variation in eDNA shedding and decay across animal forms under a range of realistic marine temperature conditions. These data will be useful for interpreting field studies that utilize eDNA to investigate ocean habitats that are otherwise difficult to access. We conducted mesocosm experiments using a fish, a crustacean, and two scyphomedusae to investigate how environmental DNA (eDNA) shedding differs between animal forms and how long eDNA can persist in waters of different temperature and light conditions. We found that shedding rates were highly variable for all organisms, but grass shrimp had the lowest eDNA shedding rate and that decay rate constants of mummichog and grass shrimp were larger at higher temperatures, while those of scyphomedusae did not show clear temperature dependence. These findings fill critical knowledge gaps regarding variation in shedding and decay of eDNA across different animal forms under a range of realistic marine temperature and light conditions.