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Differential cross sections and photon-beam asymmetries for the γ[over →]p→π^{-}Δ^{++}(1232) reaction have been measured for 0.7

The differential cross sections and decay angular distributions for coherent $\phi$-meson photoproduction from helium-4 have been measured for the first time at forward angles with linearly polarized photons in the energy range $E_{\gamma} = \text{1.685-2.385 GeV}$. Thanks to the target with spin-parity $J^{P} = 0^{+}$, unnatural-parity exchanges are prohibited, and thus natural-parity exchanges can be investigated clearly. The decay asymmetry with respect to photon polarization is shown to be very close to the maximal value. This ensures the dominance ($> 94\%$) of natural-parity exchanges in this reaction. To evaluate the contribution from natural-parity exchanges to the forward cross section ($\theta = 0^\circ$) for the $\gamma p \rightarrow \phi p$ reaction near the threshold, the energy dependence of the forward cross section ($\theta = 0^\circ$) for the $\gamma {^{4}\text{He}} \rightarrow \phi {^{4}\text{He}}$ reaction was analyzed. The comparison to $\gamma p \rightarrow \phi p$ data suggests that enhancement of the forward cross section arising from natural-parity exchanges, and/or destructive interference between natural-parity and unnatural-parity exchanges is needed in the $\gamma p \rightarrow \phi p$ reaction near the threshold.

Differential cross sections and photon-beam asymmetries for the γ[over →]p→π^{-}Δ^{++}(1232) reaction have been measured for 0.7cosθ_{π}^{c.m.}1 and E_{γ}=1.5-2.95 GeV at SPring-8/LEPS. The first-ever high statistics cross-section data are obtained in this kinematical region, and the asymmetry data for 1.5E_{γ}(GeV)2.8 are obtained for the first time. This reaction has a unique feature for studying the production mechanisms of a pure uu[over ¯] quark pair in the final state from the proton. Although there is no distinct peak structure in the cross sections, a non-negligible excess over the theoretical predictions is observed at E_{γ}=1.5-1.8 GeV. The asymmetries are found to be negative in most of the present kinematical regions, suggesting the dominance of π exchange in the t channel. The negative asymmetries at forward meson production angles are different from the asymmetries previously measured for the photoproduction reactions producing a dd[over ¯] or an ss[over ¯] quark pair in the final state. Advanced theoretical models introducing nucleon resonances and additional unnatural-parity exchanges are needed to reproduce the present data.

We report the measurement of the $\gamma p \rightarrow K^{+}\Lambda$ and $\gamma p \rightarrow K^{+}\Sigma^{0}$ reactions at SPring-8. The differential cross sections and photon-beam asymmetries are measured at forward $K^{+}$ production angles using linearly polarized tagged-photon beams in the range of $E_{\gamma}=1.5$--3.0 GeV. With increasing photon energy, the cross sections for both $\gamma p \rightarrow K^{+}\Lambda$ and $\gamma p \rightarrow K^{+}\Sigma^{0}$ reactions decrease slowly. Distinct narrow structures in the production cross section have not been found at $E_{\gamma}=1.5$--3.0 GeV. The forward peaking in the angular distributions of cross sections, a characteristic feature of $t$-channel exchange, is observed for the production of $\Lambda$ in the whole observed energy range. A lack of similar feature for $\Sigma^{0}$ production reflects a less dominant role of $t$-channel contribution in this channel. The photon-beam asymmetries remain positive for both reactions, suggesting the dominance of $K^{*}$ exchange in the $t$ channel. These asymmetries increase gradually with the photon energy, and have a maximum value of +0.6 for both reactions. Comparison with theoretical predictions based on the Regge trajectory in the $t$ channel and the contributions of nucleon resonances indicates the major role of $t$-channel contributions as well as non-negligible effects of nucleon resonances in accounting for the reaction mechanism of hyperon photoproduction in this photon energy regime.

Differential cross sections at $t={t}_{\text{min}}$ and decay asymmetries for the $\ensuremath{\gamma}p\ensuremath{\rightarrow}\ensuremath{\phi}p$ reaction have been measured using linearly polarized photons in the range 1.5 to 2.9 GeV. These cross sections were used to determine the Pomeron strength factor. The cross sections and decay asymmetries are consistently described by the $t$-channel Pomeron and pseudoscalar exchange model in the ${E}_{\ensuremath{\gamma}}$ region above 2.37 GeV. In the lower energy region, an excess over the model prediction is observed in the energy dependence of the differential cross sections at $t={t}_{\text{min}}$. This observation suggests that additional processes or interference effects between Pomeron exchange and other processes appear near the threshold region.

A search for the K − p p bound state (the lightest kaonic nucleus) has been performed using the γ d → K + π − X reaction at E γ = 1.5 – 2.4 GeV at LEPS/SPring-8. The differential cross section of the K + π − photo-production off deuterium ( d 2 σ / d cos θ K + l a b / d cos θ π − l a b ) has been measured for the first time in this energy region. A peak structure was searched for in the inclusive missing mass spectrum. A statistically significant peak structure was not observed in the region from 2.22 to 2.36 GeV/c2. The upper limits of the differential cross section of the K − p p bound state production were determined to be (0.17–0.55), (0.55–1.7) and (1.1–2.9) μb at 95% confidence level with the assumed widths of 20 MeV, 60 MeV and 100 MeV.

Evidence of the ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}\ensuremath{\nu}$ decay was searched for using E949 (Brookhaven National Laboratory, USA) experimental data with an exposure of $1.70\ifmmode\times\else\texttimes\fi{}1{0}^{12}$ stopped kaons. The data sample is dominated by the background process ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\gamma}$. An upper limit on the decay rate $\mathrm{\ensuremath{\Gamma}}({K}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}\ensuremath{\nu})l2.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}\mathrm{\ensuremath{\Gamma}}({K}^{+}\ensuremath{\rightarrow}\text{all})$ at 90% confidence level was set assuming the standard model muon spectrum. The data are presented in such a way as to allow calculation of rates for any assumed ${\ensuremath{\mu}}^{+}$ spectrum.

The $\ensuremath{\phi}\text{\ensuremath{-}}\mathrm{\ensuremath{\Lambda}}(1520)$ interference effect in the $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}p$ reaction has been measured for the first time in the energy range from 1.673 to 2.173 GeV. The relative phases between $\ensuremath{\phi}$ and $\mathrm{\ensuremath{\Lambda}}(1520)$ production amplitudes were obtained in the kinematic region where the two resonances overlap. The measurement results support strong constructive interference when ${K}^{+}{K}^{\ensuremath{-}}$ pairs are observed at forward angles but destructive interference for proton emission at forward angles. Furthermore, the observed interference effect does not account for the $\sqrt{s}=2.1\text{ }\text{ }\mathrm{GeV}$ bump structure in forward differential cross sections for $\ensuremath{\phi}$ photoproduction. This fact suggests possible exotic structures such as a hidden-strangeness pentaquark state, a new Pomeron exchange, or rescattering processes via other hyperon states.

The ϕ-Λ(1520) interference effect in the γp→K^{+}K^{-}p reaction has been measured for the first time in the energy range from 1.673 to 2.173 GeV. The relative phases between ϕ and Λ(1520) production amplitudes were obtained in the kinematic region where the two resonances overlap. The measurement results support strong constructive interference when K^{+}K^{-} pairs are observed at forward angles but destructive interference for proton emission at forward angles. Furthermore, the observed interference effect does not account for the sqrt[s]=2.1 GeV bump structure in forward differential cross sections for ϕ photoproduction. This fact suggests possible exotic structures such as a hidden-strangeness pentaquark state, a new Pomeron exchange, or rescattering processes via other hyperon states.

An emulsion-counter hybrid experiment (KEK E176) was carried out to search for double strangeness systems such as double- Λ hypernuclei and H -dibaryons. More than 10% of Ξ − hyperons produced in the (K − , K + ) reaction were brought to rest in the nuclear emulsion. We have obtained 98 candidate events of nuclear capture at rest of Ξ − hyperons which are described in this report. Among those, four events were identified as sequential weak decay of double- Λ hypernuclei. The binding energies of Ξ − -( 12 C, 14 N and 16 O) states have been estimated for two events which emit twin single- Λ hypernuclei back to back from the capture point. The Σ − p decay vertex of an H -dibaryon was searched for near the capture point and no evidence was observed. Upper limits for the branching ratio of H emission are 5–10% for a lifetime less than 0.1 ns at the 90% confidence level. The trapping probabilities of single and double strangeness to a nuclear fragment following Ξ − capture at rest have been studied.

We have investigated the effects caused by proton-induced radiation damage on Multi-Pixel Photon Counter (MPPC), a pixelized photon detector developed by Hamamatsu Photonics. The leakage current of irradiated MPPC samples linearly increases with total irradiated doses due to radiation damage, which is not completely recovered even after a year from the irradiation. No significant change has been observed in the gains at least up to 8.0 Gy ($9.1\times10^7$ n/mm$^2$ in 1 MeV neutron equivalent fluence, $\Phi_{\rm eq}$). The device has completely lost its photon-counting capability due to baseline fluctuations and noise pile-up after 21 Gy irradiation ($2.4\times10^8$ n/mm$^2$ in $\Phi_{\rm eq}$), which might be problematic for some applications, such as ring-imaging Cherenkov detectors. We have found that the pulse-height resolution has been slightly deteriorated after 42 Gy irradiation ($4.8\times10^8$ n/mm$^2$ in $\Phi_{\rm eq}$), where the measured sample has been illuminated with a few hundred photons. This effect should be considered in the case of energy-measurement applications., Comment: 18 pages, 10 figures

An event emitting a Σ- -hyperon from a Ξ- -hyperon nuclear capture at rest has been observed in a hybrid-emulsion experiment. The event has been analyzed as the first observation of the weak decay of the S = - 2 system.

Evidence of a heavy neutrino, ν H , in the K + → μ + ν H decays was sought using the E949 experimental data with an exposure of 1.70 × 1 0 12 stopped kaons. With the major background from the radiative K + → μ + ν μ γ decay understood and suppressed, upper limits (90% C.L.) on the neutrino mixing matrix element between the muon and heavy neutrinos, | U μ H | 2 , were set at the level of 1 0 - 7 to 1 0 - 9 for the heavy neutrino mass region 175 to 300 MeV / c 2 .

The performance of connected GSO (Gd 2 SiO 5 :Ce) bars was investigated using a proton beam of 0.6–1.0 GeV/ c . Single crystals of 20 cm-long GSO with different Ce concentrations (1.5, 0.5 mol%) and cross-sections (1×1 cm 2 , 2×2 cm 2 ) were prepared. Long GSO bars were constructed by connecting two crystals of the same type with or without a 10 cm-long plastic scintillator between the crystals. The position dependences of the pulse height, energy resolution and time resolution were investigated. At a typical proton momentum, 1.0 GeV/ c , the best energy resolution was 4.8% for 2×2×20 cm 3 GSO crystals doped with 0.5 mol% Ce due to the larger light yield, and the best position resolution was 0.55 cm for 1.5 mol% Ce due to the shorter attenuation length.

We have searched for the K{sup +} {yields} {pi}{sup +}{gamma}{gamma} decay in the kinematic region with {pi}{sup +} momentum close to the end point. No events were observed, and the 90% confidence-level upper limit on the partial branching ratio was obtained, B(K{sup +} {yields} {pi}{sup +}{gamma}{gamma}, P > 213 MeV/c) < 8.3 x 10{sup -9} under the assumption of chiral perturbation theory including next-to-leading order ''unitarity'' corrections. The same data were used to determine an upper limit on the K{sup +} {yields} {pi}{sup +}{gamma} branching ratio of 2.3 x 10{sup -9} at the 90% confidence level.

A new programmable trigger board and digital mean-timer modules using complex programmable logic device have been introduced to the trigger system of the BNL-E949 experiment. The online dead time was reduced from 4.0% to 1.7% by introducing an on-chip prescaler to the programmable trigger board. The acceptance loss of the online photon veto was reduced from 4.9% to 1.8% by introducing the mean-timer modules.

PbWO 4 heavily doped with trivalent rare-earth ions like La 3+ , Gd 3+ , Y 3+ , etc. has recently been proposed as an excellent new, heavy and radiation-hard Cherenkov radiator, and the upper limit of the remaining scintillation light yield (LY) was obtained from measurement of radioisotope γ-rays. Since then, we have made a quantitative study of the remaining scintillation LY using a 0.5–1 GeV/ c π + /p/d beam. Compared with a standard PbWO 4 : Gd(80 at ppm) scintillator, the scintillation LY is quenched to 4.8%, 6.0%, and 11.6% for La 3+ concentration of 8 at%, La 3+ of 5 at% and Gd 3+ of 3 at%, respectively. The scintillation LY remaining in PbWO 4 : La(8 at%) was as weak as 15% of the Cherenkov LY for relativistic charged particles.

Sirs: Patients with CreutzfeldtJakob disease (CJD) may be associated with iatrogenic transmission including brain or eye surgery, cadaveric pituitary extracts for growth hormone or gonadotropin therapy, and implantation of cadaveric dura mater grafts during neurosurgical procedures [2]. In recent years dural graft-associated cases have been increasing in number, especially in Japan [4, 11]. We describe an autopsy-confirmed case of CJD, in which cadaveric dura mater graft was implanted in the right posterior cranial fossa for Jannetta’s operation 167 months before the onset. The patient presented with vertigo and nystagmus as initial manifestations, and neuro-otological examinations suggested an initial lesion adjacent to the grafted site. A 69-year-old woman developed vertigo in the middle of May 1998. On 19 July 1984, 167 months before the onset of the vertigo, the patient underwent Jannetta’s operation for right hemifacial spasm to reduce vascular compression to the right facial nerve, and received a lyophilized cadaveric dural patch (Lyodura®) for the repair of a dural defect covering the surface of the right cerebellar hemisphere. The operation was successful and she left the hospital with neither facial spasm nor other neurological symptoms. Since her vertigo worsened, the patient was admitted to our Otorhinolaryngological Clinic on 14 July 1998. On admission, her mental status appeared normal. Neurological examinations showed no abnormalities except for neurootological findings. In the ocular movement, smooth pursuit was impaired bilaterally (Fig. 1a). The response to optokinetic stimulation was also impaired. There was spontaneous nystagmus toward right direction under calculation task with eyes open in the dark room. Saccadic eye movement was not impaired. The patient occasionally complained of diplopia when she was gazing toward right or upward, although there appeared to be no limitation in the range of the eye movement. These findings suggested that the right side of flocculus and paraflocculus would be damaged with mild involvement of the right oculomotor nucleus [9], and that the cerebellar vermis was not affected [9]. On 21 July, up-beat nystagmus was observed in a positioning test, and visual suppressions in bilateral caloric tests were disturbed. Impairment of smooth pursuits (Fig. 1b), visual suppression, and the response to optokinetic stimulation rapidly worsened, and dysmetria in the saccade test was observed. These suggested that cerebellar vermis and fastigial nucleus were also impaired [9]. On 4 August, fast phase velocity toward the right was revealed to be slow. Thereafter, her spontaneous speech much decreased, and abnormal behavior appeared. The patient was admitted to our Neurological Clinic on 13 August. On admission, she was alert, however orientation for time and place and calculation were severely impaired; other cognitive functions could not be evaluated. The patient showed no vertigo, diplopia, or nystagmus. Although movements were generally slow, muscle tone and power were normal. There was no involuntary movement including myoclonus. Tendon reflexes were all normal. Babinski’s sign was negative bilaterally. Her gait was ataxic; however, the finger-to-nose test, pronation-supination movement, and heel-to-knee test were normal. Romberg sign was negative. Sensory and autonomic systems were normal. Blood and urinary examinaLETTER TO THE EDITORS

A hybrid experiment with nuclear emulsion and scintillating-fiber detectors (KEK-E373) has been performed to search for double-strangeness systems. Among about 10${}^{3}$ events of ${\ensuremath{\Xi}}^{\ensuremath{-}}$ hyperons captured at rest by emulsion nuclei, we have observed four events which clearly show the topology of cascade weak decays of double-$\ensuremath{\Lambda}$ hypernuclei including the ``Nagara'' event. Regarding the Nagara event, values of the two-$\ensuremath{\Lambda}$ binding energy (${B}_{\ensuremath{\Lambda}\ensuremath{\Lambda}}$) and the $\ensuremath{\Lambda}$-$\ensuremath{\Lambda}$ interaction energy ($\ensuremath{\Delta}{B}_{\ensuremath{\Lambda}\ensuremath{\Lambda}}$) of ${}_{\ensuremath{\Lambda}}^{}{}_{\ensuremath{\Lambda}}^{6}\mathrm{He}$ have been revised to 6.91 $\ifmmode\pm\else\textpm\fi{}$ 0.16 and 0.67 $\ifmmode\pm\else\textpm\fi{}$ 0.17 MeV, respectively, due to the recent change of the ${\ensuremath{\Xi}}^{\ensuremath{-}}$ mass value (Particle Data Group). For another three events, we have determined possible species of double-$\ensuremath{\Lambda}$ hypernuclei together with their binding energies.

The exclusive reaction γp→K(+)π(-)Σ(+) was measured for the first time using linearly polarized photons at beam energies from 1.85 to 2.96 GeV. Angular distributions in the rest frame of the K(+)π(-) system were fitted to extract spin-density matrix elements of the K(*0) decay. The measured parity spin asymmetry shows that natural-parity exchange is dominant in this reaction. This result clearly indicates the need for t-channel exchange of the κ(800) scalar meson.

The exclusive reaction γp→K(+)π(-)Σ(+) was measured for the first time using linearly polarized photons at beam energies from 1.85 to 2.96 GeV. Angular distributions in the rest frame of the K(+)π(-) system were fitted to extract spin-density matrix elements of the K(*0) decay. The measured parity spin asymmetry shows that natural-parity exchange is dominant in this reaction. This result clearly indicates the need for t-channel exchange of the κ(800) scalar meson.

A measurement of the decay K{sup +{yields}{pi}0{mu}+{nu}}{sub {mu}{gamma}}has been performed with the E787 detector at Brookhaven National Laboratory. Forty events were observed in the signal region with the background expectation of (16.5{+-}2.7) events. The branching ratio was measured to be (1.58{+-}0.46(stat.){+-}0.08(syst.))x10{sup -5} in the kinematic region E{sub {gamma}>}30 MeV and {theta}{sub {mu}{gamma}>}20 deg., where E{sub {gamma}}is the energy of the emitted photon and {theta}{sub {mu}{gamma}}is the angle between the muon and the photon in the K{sup +} rest frame. The results were consistent with theoretical predictions.

Experiment E949 at Brookhaven National Laboratory has observed three new events consistent with the decay ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ in the pion momentum region $140l{P}_{\ensuremath{\pi}}l199\text{ }\text{ }\mathrm{MeV}/c$ in an exposure of $1.71\ifmmode\times\else\texttimes\fi{}{10}^{12}$ stopped kaons with an estimated total background of $0.93\ifmmode\pm\else\textpm\fi{}0.17(\mathrm{stat}{)}_{\ensuremath{-}0.24}^{+0.32}(\mathrm{syst})$ events. This brings the total number of observed ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ events to seven. Combining this observation with previous results, assuming the pion spectrum predicted by the standard model, results in a branching ratio of $\mathcal{B}({K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}})=({1.73}_{\ensuremath{-}1.05}^{+1.15})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$. An interpretation of the results for alternative models of the decay ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}+nothing$ is also presented.

Sewage sludge melting has been developed and operated in full-scale plants for sludge processing and utilization of the by-products as construction materials. Hazardous asbestos wastes should be disposed of properly so not to lead to environmental pollution. The co-melting process for sewage sludge and asbestos wastes is discussed based on the basic melting behavior of asbestos and the laboratory plant experiment. Microscopic observation and X-ray diffraction analysis showed that asbestos forms could be changed physically and chemically by the high temperature melting. The disappearance of asbestos fibrous forms and chemical changes of its composition in the melted slag are not always concluded to be non-toxic, but considering that the melted slag is a rock-like material with high strength, the melting is acceptable as a method of hazardous asbestos waste disposal. Laboratory scale experiments have been conducted on co-melting disposal of sprayed-on chrysotile asbestos waste and a mixture of lime-added and polymer-added sewage sludge. It was possible to maintain the temperatures around 1600 °C and to discharge slag smoothly. It is also expected that asbestos cement wastes will contribute to the adjustment materials of basicity (CaO/SiO2) in the polymer-added sludge melting.

Three events for the decay K+-->pi+ nunu have been observed in the pion momentum region below the K+-->pi+pi0 peak, 140 pi+ nunu) = (1.73(-1.05)+1.15) x 10(-10) consistent with the standard model prediction.

Three events for the decay K+--pi+ nunu have been observed in the pion momentum region below the K+--pi+pi0 peak, 140Ppi199 MeV/c, with an estimated background of 0.93+/-0.17(stat.) -0.24+0.32(syst.) events. Combining this observation with previously reported results yields a branching ratio of B(K+--pi+ nunu) = (1.73(-1.05)+1.15) x 10(-10) consistent with the standard model prediction.

Double hypernuclei are important to add the 3rd dimension to the chart of nulei. It is expected that more events of double hypernuclei exist in the emulsion of the KEK-PS E373 experiment. We are developing a new method, which is called general scan, in order to find more double hypernuclei. The current status of analysis with a general scan is reported.

Experiment E949 at Brookhaven National Laboratory studied the rare decay K{sup +}-->pi{sup +} nu{ovr {nu}} and other processes with an exposure of 1.77 x 10{sup 12} k{sup +}'s. The data were analyzed using a blind analysis technique yielding one candidate event with an estimated background of 0.30 {+-} 0.03 events. Combining this result with the observation of two candidate events by the predecessor experiment E787 gave the branching ratio B(K{sup +}-->pi{sup +} nu{ovr {nu}}) = (1.47{sub -0.89}{sup +1.30}) x 10{sup -10}, consistent with the standard model prediction of (0.74 {+-} 0.20) x 10{sup -10}. This is a more detailed report of results previously published [V.V. Anisimovsky et al., Phys. Rev. Lett. 93, 031801 (2004)].

A sewage sludge melting process has been developed and some full-scale planls have been installed or are now under construction in Japan. Sludge melting process has its main advantages in that most sorts of hazardous materials, such as heavy metals, are tightly fixed in solid phase and the slag produced by this process can be used as construction materials. This article analyzes sludge treatment and disposal costs of the popular sludge treatment alternatives with emphasis on thermal processes, especially the sludge melting process. From preliminary system designs on a common design basis, relative energy requirements and total treatment & disposal costs were compared. As a result of cost analysis in terms of the annual treatment cost, it was revealed that the lime conditioning systems cost some 50% more than the polymer conditioning, that in a comparison between the incineration and the melting systems the treatment cost differed when the difference in energy cost was significant, and that in the anaerobic digestion systems the superiority in energy balance did not contribute to treatment cost reduction. Even if as one of the cost conditions to introduce the melting system in place of the incineration system, the ash disposal price is set as low as 5,000 yen/t, the coke melting system is still advantageous in the lime conditioning. Further, it turned out that in the polymer conditioning systems it was possible to establish cost conditions to introduce the melting system when the incinerated ash disposal price, the melting process coke ratio and the coke price took certain values.

We report the measurement of differential cross sections for $\omega$ and $\eta'$ photoproduction from protons at backward angles ($-1.0 2.4$ GeV. A bump structure in the $\sqrt{s}$ dependence of the differential cross sections for $\eta'$ mesons was observed at $\sqrt{s}\sim$2.35 GeV.

A sample of kinematically identified K{sup +}{yields}{pi}{sup +}{pi}{sup 0} decays obtained with the E949 detector was used to search for the helicity-suppressed decay {pi}{sup 0}{yields}{nu}{nu} resulting in an upper limit of 2.7x10{sup -7} at 90% confidence level. The upper limit is also applicable to {pi}{sup 0} decays into unknown weakly-interacting particles.

An additional event near the upper kinematic limit for K+ to pi+ nu nubar has been observed by Experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+ to pi+ nu nubar)= 1.47 (+1.30, - 0.89) x 10-10 based on three events observed in the pion momentum region 211

An additional event near the upper kinematic limit for K+--pi(+)nunu; has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, the branching ratio is B(K+--pi(+)nunu;)=(1.47(+1.30)(-0.89))x10(-10) based on three events observed in the pion momentum region 211P229 MeV/c. At the measured central value of the branching ratio, the additional event had a signal-to-background ratio of 0.9.

Vocal cord abductor paralysis (VCAP) is considered a sign of a poor prognosis in neurodegenerative diseases, because severe laryngeal dysfunction by VCAP may result in acute airway obstruction and require emergency tracheotomy.1 Although VCAP is a cardinal feature in multiple system atrophy (MSA), it has not been reported in several types of spinocerebellar ataxia with dominant inheritance. We evaluated the movements of the vocal cords of seven patients with SCA1 by laryngofibroscopy. Seven unrelated patients with SCA1 who had the expanded CAG repeat of ataxin-1 were investigated. There were two men and five women ranging in age from 27 to 67 years old (mean 44.5 years). Spouses and other family members, in addition to the patients, were questioned about events of stridor, dyspnoea, and dysphagia. Vocal cord movement was examined by laryngofibroscopy and recorded during inspiration and phonation. The rating scale used to evaluate maximal abduction of the vocal …

A sewage sludge melting process by coke - bed furnace, which is an application of cupola melting technology, was developed. The outline of the course of the development from the bench - scale experiment to the construction of a commercial plant is described. The process is a more sophisticated one which enables high volume reduction, stabilization and utilization of sewage sludge. The slag produced by the process has a volume reduction ratio of 1/9 to 1/40 compared with dewatered sludge, and potential to be utilized as road subbase material and concrete aggregate. The operational cost of the process is estimated to be comparable to that of the conventional ones.