We report the first observation of the decay Λ_{c}^{+}→pK^{+}π^{-} using a 980 fb^{-1} data sample collected by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. This is the ...first observation of a doubly Cabibbo-suppressed decay of a charmed baryon. We measure the branching ratio of this decay with respect to its Cabibbo-favored counterpart to be B(Λ_{c}^{+}→pK^{+}π^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})=(2.35±0.27±0.21)×10^{-3}, where the uncertainties are statistical and systematic, respectively.
Aliquat-336 as a novel collector for quartz flotation Sahoo, H.; Rath, S.S.; Jena, S.K. ...
Advanced powder technology : the international journal of the Society of Powder Technology, Japan,
03/2015, Volume:
26, Issue:
2
Journal Article
Peer reviewed
Display omitted
•Aliquat-336 is a novel collector in the flotation of quartz from BHQ ore.•65% Fe grade with 60% recovery was achieved from a lean ore containing 38% Fe.•No frother used in the ...flotation is an added advantage.
The study illustrates the first ever use of Aliquat-336 (C25H54ClN), an ionic liquid, in the flotation separation of quartz from hematite. Laboratory flotation studies of hematite, quartz and their synthetic mixture have shown selective collecting action of Aliquat-336 toward quartz. At an Aliquat-336 dosage of 280g/t, 97% quartz is floated at slightly alkaline pH (∼8), whereas hematite recovery is only 8%. Flotation of the synthetic mixture of hematite: quartz (1:1), with Aliquat-336 as the quartz collector and starch as the hematite depressant, has resulted in an iron concentrate of 63–65% Fe with 85–88% recovery. The reverse flotation behavior of the low grade banded hematite quartzite (BHQ) using Aliquat-336 as the collector has been investigated. It is observed that, iron values up to ∼65% Fe with 60% recovery can be achieved from the ore containing ∼38% Fe. Surface potential measurement and FTIR spectra lead to the indication of electrostatic adsorption between Aliquat-336 and quartz.
We report a search for a dark vector gauge boson U′ that couples to quarks in the decay chain D*+→D0π+,D0→KS0η,η→U′γ, U′→π+π−. No signal is found and we set a mass-dependent limit on the baryonic ...fine structure constant of 10−3−10−2 in the U′ mass range of 290 to 520 MeV/c2. This analysis is based on a data sample of 976 fb−1 collected by the Belle experiment at the KEKB asymmetric-energy e+e− collider.
Equal amounts of matter and antimatter are predicted to have been produced in the Big Bang, but our observable Universe is clearly matter-dominated. One of the prerequisites for understanding this ...elimination of antimatter is the nonconservation of charge-parity (CP) symmetry. So far, two types of CP violation have been observed in the neutral K meson (K0) and B meson (B0) systems: CP violation involving the mixing between K0 and its antiparticle (and likewise for B0 and ), and direct CP violation in the decay of each meson. The observed effects for both types of CP violation are substantially larger for the B0 meson system. However, they are still consistent with the standard model of particle physics, which has a unique source of CP violation that is known to be too small to account for the matter-dominated Universe. Here we report that the direct CP violation in charged B±→K± 0 decay is different from that in the neutral B0 counterpart. The direct CP-violating decay rate asymmetry, (that is, the difference between the number of observed B-→K- 0 event versus B+→K+ 0 events, normalized to the sum of these events) is measured to be about +7%, with an uncertainty that is reduced by a factor of 1.7 from a previous measurement. However, the asymmetry for versus B0→K+ - is at the -10% level. Although it is susceptible to strong interaction effects that need further clarification, this large deviation in direct CP violation between charged and neutral B meson decays could be an indication of new sources of CP violation-which would help to explain the dominance of matter in the Universe.
We have developed a prototype detector and data acquisition module that incorporates wireless power and wireless data transmission techniques. The module has no electrical connections. It receives ...power using photovoltaic devices, and communicates control, timing, trigger, and data using the 802.11n wireless communication standard. The work is part of a study for building a large detector having many readout channels, where it is desirable to reduce the cable plant and infrastructure. The system could also be deployed in smaller detectors that require mobility or are difficult to cable due to extreme conditions. We describe the design and operation of the prototype module, including benchmark performance measurements, and discuss aspect and issues in extrapolating to a large detector system.
We search for bottomonium states in Υ(2S) → (bb)γ decays with an integrated luminosity of 24.7 fb(-1) recorded at the Υ(2S) resonance with the Belle detector at KEK, containing (157.8±3.6)×10(6) ...Υ(2S) events. The (bb) system is reconstructed in 26 exclusive hadronic final states composed of charged pions, kaons, protons, and K(S)(0) mesons. We find no evidence for the state recently observed around 9975 MeV (X(bb)) in an analysis based on a data sample of 9.3×10(6) Υ(2S) events collected with the CLEO III detector. We set a 90% confidence level upper limit on the branching fraction BΥ(2S) → X(bb)γ × ∑(i)BX(bb) → h(i) < 4.9×10(-6), summed over the exclusive hadronic final states employed in our analysis. This result is an order of magnitude smaller than the measurement reported with CLEO data. We also set an upper limit for the ηb(1S) state of BΥ(2S) → ηb(1S)γ × ∑(i)Bηb(1S) → h(i) < 3.7×10(-6).
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