Based on the analysis of tuyere sampling performed in PCR increasing stage of Muroran No. 2 blast furnace of Hokkai Iron & Coke Corporation, examination was made on the influence of ash originated in ...pulverized coal in high-productivity, high PCR operation upon physical property of dripping slag or packed structure at dead man surface extending from raceway end. The amount of dripping slag with which ash originated in pulverized coal reacts and assimilates is 15–20% of the total amount of dripping slag, and the components of dripping slag distribute in a circumferential direction between inside of raceway and outside of raceway as well as in a radial direction including the inside of raceway and dead man. When PCR is high, high-vicious -1 mm fine at the dead man surface from the vicinity of raceway and high CaO/SiO2 -1 mm fine and dripping slag between raceway and in dead man, with the increase of -3 mm fine, are supposed to be one of the main causes deteriorating the gas and liquid permeabilities at the dead man surface and lowering the dead man temperature. For establishing a technology assuring a stable furnace operation over a long period, it is necessary to take the measures for improving deterioration in gas and liquid permeabilities at the dead man surface due to not only -3 mm fine and unburnt char but also pulverized coal ash.
The International Linear Collider (ILC) and other proposed high energy e super(+)e super(-) machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered ...phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 10 super(-4). This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006-2007 in SLAC's End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5 times 10 super(-4) was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance.
Cavity BPM system tests for the ILC energy spectrometer Slater, M.; Adolphsen, C.; Arnold, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2008, Letnik:
592, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The main physics programme of the International Linear Collider (ILC) requires a measurement of the beam energy at the interaction point with an accuracy of
10
-
4
or better. To achieve this goal a ...magnetic spectrometer using high resolution beam position monitors (BPMs) has been proposed. This paper reports on the cavity BPM system that was deployed to test this proposal. We demonstrate sub-micron resolution and micron level stability over 20
h for a
1
m
long BPM triplet. We find micron-level stability over 1
h for 3 BPM stations distributed over a
30
m
long baseline. The understanding of the behaviour and response of the BPMs gained from this work has allowed full spectrometer tests to be carried out.
We study B+/ --> J/psi pi(+/-) and B+/ --> J/psi K+/- decays in a sample of about 89 x 10(6) BB pairs collected with the BABAR detector at the PEP-II asymmetric B factory at SLAC. We observe a signal ...of 244+/-20 B+/ --> J/psi pi(+/-) events and determine the ratio B(B+/ --> J/psi pi(+/-))/B(B+/ --> J/psi K+/-) to be 5.37+/-0.45(stat)+/-0.11(syst)%. The charge asymmetries for the B+/ --> J/psi pi(+/-) and B+/ --> J/psi K+/- decays are determined to be A(pi)=0.123+/-0.085(stat)+/-0.004(syst) and A(K)=0.030+/-0.015(stat)+/-0.006(syst), respectively.
In the injection test of serpentine through one tuyere executed as a means to improve the furnace lower filling structure, the tuyere sampler insertion depth and the deadman temperature rose greatly ...by the amount of the fine serpentine injection of 20 kg/t or more. It is presumed for the melting point of slag piling up in the deadman surface part to decrease by the injection of fine serpentine through tuyere, for the fine ratio (−3 mm) of the melt origin and a slag hold-up ratio to decrease greatly, and for the gas and liquid permeabilities in deadman to have been improved. In addition, the possibility that the desulfurization reaction is able to be promoted efficiently while maintaining the active state of deadman and the possibility of the low temperature operation by the serpentine injection through tuyere were suggested.
We present measurements of branching fractions and charge asymmetries for six B -meson decay modes with an η or η ′ meson in the final state. The data sample corresponds to 232 × 10 6 B ¯¯¯ B pairs ...collected with the BABAR detector at the PEP-II asymmetric-energy e + e − B Factory at SLAC. We measure the branching fractions (in units of 10 − 6 ): B ( B + → η π + ) = 5.1 ± 0.6 ± 0.3 , B ( B + → η K + ) = 3.3 ± 0.6 ± 0.3 , B ( B 0 → η K 0 ) = 1.5 ± 0.7 ± 0.1 ( < 2.5 at 90% C.L.), B ( B + → η ρ + ) = 8.4 ± 1.9 ± 1.1 , B ( B 0 → η ω ) = 1.0 ± 0.5 ± 0.2 ( < 1.9 at 90% C.L.), and B ( B + → η ′ π + ) = 4.0 ± 0.8 ± 0.4 , where the first uncertainty is statistical and second systematic. For the charged modes we also determine the charge asymmetries, all found to be compatible with zero.
We search for the factorization-suppressed decays B → χ c 0 K ( * ) and B → χ c 2 K ( * ) , with χ c 0 and χ c 2 decaying into J / ψ γ , using a sample of 124 × 10 6 B ¯¯¯ B events collected with the ...BABAR detector at the PEP-II storage ring of the Stanford Linear Accelerator Center. We find no significant signal and set upper bounds for the branching fractions.
Using a data sample corresponding to an integrated luminosity of 342 $fb^{-1}$ collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy ...near 10.58 GeV, we measure ${\cal{B}} (\tau^- \to \pi^- \pi^- \pi^+ \nu_\tau) = (8.83 \pm 0.01 \pm 0.13) %$, ${\cal{B}} (\tau^- \to K^- \pi^- \pi^+ \nu_\tau) = (0.273\pm 0.002\pm 0.009)%$, ${\cal{B}} (\tau^- \to K^- \pi^- K^+ \nu_\tau) = (0.1346\pm 0.0010 \pm 0.0036)%$ and ${\cal{B}} (\tau^- \to K^- K^- K^+ \nu_\tau) = (1.58\pm 0.13 \pm 0.12)\times 10^{-5}$, where the uncertainties are statistical and systematic, respectively. Events where the $\pi^+\pi^-$ pair is consistent with coming from a $K^0_S$ are excluded. These are significant improvements over previous measurements, with the ${\cal{B}} (\tau^- \to K^- K^- K^+ \nu_\tau)$ result being the first resonant plus non-resonant measurement of this mode. We also report a first measurement of ${\cal{B}} (\tau^- \to \phi\pi^- \nu_\tau) = (3.42\pm 0.55 \pm 0.25)\times 10^{-5}$ and a new measurement of ${\cal{B}} (\tau^- \to \phi K^- \nu_\tau) = (3.39\pm 0.20 \pm 0.28)\times 10^{-5}$.