Search

The asymmetry parameter, A/sub ..beta../, in the positron decay of polarized /sup 58/Co has been measured to be +0.341 +- 0.013. Assuming the standard T-invariant V-A weak interaction theory, the Fermi to Gamow-Teller mixing ratio, y = C/sub V/M/sub F//C/sub A/M/sub GT/, was determined to be -0.005 +- 0.008. The vanishing value of y is consistent with the isospin selection rule for the Fermi matrix element.

We have measured elastic ..nu../sub ..mu../ and nu-bar/sub ..mu../ scattering on protons at the Brookhaven National Laboratory Alternating Gradient Synchrotron. We find R/sub NC/ = sigma(nu-bar/sub ..mu../p..-->..nu-bar/sub ..mu../p) / sigma(..nu../sub ..mu../p..--> nu../sub ..mu../p) = 0.44 +- 0.12 and R/sub numu/ = sigma(..nu../sub ..mu../p..--> nu../sub ..mu../p)/sigma(..nu../sub ..mu../n..--> mu../sup -/p) = 0.11 +- 0.03. The elastic Q/sup 2/ distribution is in good agreement with present knowledge of form factors and the Weinberg-Salam model. We find sin/sup 2/theta/sub W/ = 0.26 +- 0.06.

A very narrow resonance with a mass of 3.105 GeV/${\mathit{c}}^{2}$ is observed in the reaction $\ensuremath{\gamma}+\mathrm{Be}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}+{\ensuremath{\mu}}^{\ensuremath{-}}+X$. The total cross section for this process, as well as its $t$ distribution, is given.

We have constructed and operated a set of two parallel plate, segmented ionization chambers, to monitor the secondary charged particle flux in the narrow band neutrino beam at the AGS. These chambers were operated successfully in a high instantaneous flux (∼5 × 1014cm−2s−1) environment, with linear response to beam intensity. They have been used to monitor the targeting of the primary proton beam, and provide measurements of the secondary beam profile as well as the absolute beam intensity in the tunnel.

A very narrow resonance with a mass of 3.1 GeV/${\mathit{c}}^{2}$ is observed in the reaction $n+\mathrm{Be}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}+{\ensuremath{\mu}}^{\ensuremath{-}}+X$. The total cross section for this process, as well as its ${{P}_{\ensuremath{\perp}}}^{2}$ and $x$ distribution, are given.

The reaction ..nu..p ..-->.. ..nu..p has been observed in an experiment conducted at the Brookhaven AGS. Experimental details and a comparison with quasi-elastic neutrino scattering are presented.

A new high-precision measurement of the asymmetry coefficient, ${A}_{\ensuremath{\beta}}$, for the positron decay of polarized $^{56}\mathrm{Co}$ is reported: ${A}_{\ensuremath{\beta}}=+0.359\ifmmode\pm\else\textpm\fi{}0.009$. If one assumes the $V\ensuremath{-}A$ form of the weak interaction and time-reversal invariance, the Fermi-Gamow-Teller mixing ratio, $y=\frac{{C}_{V}{M}_{F}}{{C}_{A}{M}_{\mathrm{GT}}}$, is then -0.091\ifmmode\pm\else\textpm\fi{}0.005. Since $y$ is nonzero and isospin is not conserved, $^{56}\mathrm{Co}$ ${\ensuremath{\beta}}^{+}$ decay is a good candidate for sensitive time-reversal invariance tests of the weak interaction.

We have measured the total cross sections of ${\ensuremath{\Omega}}^{\ensuremath{-}}$ and ${\overline{\ensuremath{\Omega}}}^{+}$ forward (${x}_{\mathrm{F}}g~0$) inclusive production in ${K}_{L}^{0}$-carbon interactions in the range ${E}_{{K}^{0}}=80 \mathrm{to} 280$ GeV to be 3.5\ifmmode\pm\else\textpm\fi{}1.4 and 2.4\ifmmode\pm\else\textpm\fi{}1.0 \ensuremath{\mu}b, respectively. We observe that the ${x}_{\mathrm{F}}$ distributions for both of these states are increasing from ${x}_{\mathrm{F}}=0$ to ${x}_{\mathrm{F}}\ensuremath{\approx}0.6$. The ${p}_{\ensuremath{\perp}}^{2}$ distributions are described as an exponential function in ${p}_{\ensuremath{\perp}}$ with an average ${p}_{\ensuremath{\perp}}^{2}$ of 0.540 Ge${\mathrm{V}}^{2}$/${\mathit{c}}^{2}$.

In this talk I will discuss the following subjects: 1. the first observation of the reaction νμ + p → νμ + p and the measurement of the ratio \( {R_{{el}}} = \frac{{\sigma \left( {{v_{\mu }} + p \to {v_{\mu }} + p} \right)}}{{\sigma \left( {{v_{\mu }} + n \to \mu \overline {} + p} \right)}} \) 2. the study of the reactions νμ + N → νμ+ N′ + π0 and νμ + N → νμ+ N′ + π0 3. the observation of νμ + N → μ + e +…

Traffic watermarking is an important element in many network security and privacy applications, such as tracing botnet C&C communications and deanonymizing peer-to-peer VoIP calls. The state-of-the-art traffic watermarking schemes are usually based on packet timing information and they are notoriously difficult to detect. In this paper, we show for the first time that even the most sophisticated timing-based watermarking schemes (e.g., RAINBOW and SWIRL) are not invisible by proposing a new detection system called BACKLIT. BACKLIT is designed according to the observation that any practical timing-based traffic watermark will cause noticeable alterations in the intrinsic timing features typical of TCP flows. We propose five metrics that are sufficient for detecting four state-of-the-art traffic watermarks for bulk transfer and interactive traffic. BACKLIT can be easily deployed in stepping stones and anonymity networks (e.g., Tor), because it does not rely on strong assumptions and can be realized in an active or passive mode. We have conducted extensive experiments to evaluate BACKLIT's detection performance using the PlanetLab platform. The results show that BACKLIT can detect watermarked network flows with high accuracy and few false positives.