The dielectric constants and loss angles of a series of concentrated aqueous ionic solutions have been measured at wave-lengths of 10 cm, 3 cm, and 1.25 cm. From these results the values of the static dielectric constant and relaxation time for these solutions have been calculated on the basis of the Debye formula, which appears to hold accurately. All salts show a lowering of the dielectric constant and a shift in the relaxation time of water. It is found that the dielectric constant ε can be represented by a formula ε=εω+2δ̄c, where εω is the dielectric constant of water, c is the concentration in moles per liter, and δ has values between −7 and −15 for various salts in concentrations of up to 2 M. In Part I the measurements are described and the results discussed in relation to the structure of ionic solutions. In Part II the validity of the Debye-Sack saturation theory of the dielectric constant and the effects of the fall of dielectric constant on the electrolytic properties of concentrated solutions are discussed.

The s and? dependence of incoherent #(3100) photoproduction from deuterium has been measured at the Stanford Linear Accelerator Center. #(3700) photoproduction and #(3100) photoproduction from hydrogen have also been measured.

Exclusive photoproduction cross sections have been measured for the processes y p + r + n , y p -r a p , y p i r r -~+ + , y p i p o P , y p -' K + A , and y p i K + z O at large t and u values at several energies for each process between 4 and 7.5 GeV. These measurements taken together with past data taken at small values of t and u provide complete angular distributions. The data show the usual small t and u peaks and a central region in which the cross section decreases approximately as s -'. The results are discussed within the context of parton or constituent models.

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J/ip photoproduction has been measured from beryllium and tantalum targets by observing the yield of single muons at a transverse momentum of 1.65 GeV/c with a bremsstrahlung beam of £ 0 = 20 GeV. The results have been interpreted in terms of a nuclearoptics model to yield the ^-nucleon total cross section. The result is oty A = 3.5± 0.8 mb.A search for ixe events produced in an antineutrino hydrogen-neon experiment using the Fermilab 15-ft bubble chamber is reported. Based on a single candidate, the 90%-confidence upper limit for the relative yield of ii+e~ events is 0.5% of all charged-current events with antineutrino energy greater than 10 GeV.

von Storch et al. (Reports, 22 October 2004, p. 679) criticized the ability of the ''hockey stick'' climate field reconstruction method to yield realistic estimates of past variation in Northern Hemisphere temperature. However, their conclusion was based on incorrect implementation of the reconstruction procedure. Calibration was performed using detrended data, thus artificially removing a large fraction of the physical response to radiative forcing. found that the MBH-style reconstructions underestimated the amplitude of true simulated northern hemisphere temperatures by a factor of up to three or more Efigure 2A in (1); the exact factor depends on the amount of noise included in the pseudoproxies.^. VS04 thus reasoned that MBH could have systematically underestimated past temperature excursions by similar factors. This critique has assumed political importance, being cited in a congressional inquiry concerning the MBH reconstruction (4). It has gone unnoted that the VS04 analysis differed critically from the procedures used by MBH, which bears directly on the validity of the VS04 critique.MBH (see Fig. 1A) calibrated proxies against time series of dominant instrumental temperatures patterns over 1902 to 1980 in a procedure guaranteeing (by construction) retention of sample mean and variance, and thus the calibration period trend (2, 3). MBH additionally validated the reconstructions over an independent time span, 1854 to 1901 (called the Bverification[ period) (2, 3), during which at least mean (lowfrequency) tracking of instrumental temperatures must also be demonstrated. Figure 1B shows the corresponding VS04 results, with two pseudoproxy-based estimates of the true model temperatures. The B75% noise[ curve is the case from VS04 Efigure 2A in (1)^that shows proxy-based reconstructions underestimating the amplitude of true ECHO-G temperatures by more than a factor of three. Although there is strong agreement in MBH between observed and reconstructed temperatures in the 1902 to 1980 calibration period, and good performance in capturing mean temperature during the verification period (Fig. 1A), the results in VS04 are very different (Fig. 1B). Large, systematic amplitude losses appear between the reconstructed and true (simulated) temperatures over both the calibration and verification periods, even though their temporal structures remain similar. In fact, the VS04 results could be closely mimicked by applying scaling factors to the ECHO-G output that reflect the amounts of noise added to construct the pseudoproxiesfactors the MBH method would necessarily assimilate in calibration. The systematic amplitude losses in calibration and verification in VS04 indicate highly unsuccessful validation, which would have led to dismissal of the reconstruction results in a real-world paleoclimate analysis and clearly demonstrate a fundamental discrepancy from the MBH algorithm. Therefore, the VS04 results (1) cannot speak to the question of whether (and if so, why) the MBH procedure causes large losses of low frequency var...

We have completed measurements of the differential cross section for y + prro + p , and the asymmetry with polarized photons, for incident photon energies from 4 to 18 GeV and momentum transfers between t = -0.1 and -1.4 (~e v / c ) ' . The experiment was performed at the Stanford Linear Accelerator Center, using the SLAC 1.6-GeV/c spectrometer to analyze protons recoiling from a hydrogen target. For the cross-section measurements a normal collimated bremsstrahlung beam was used. For the asymmetry measurements the polarized photons were produced by coherent bremsstrahlung from a diamond crystal, and a coincidence was required between the recoil proton and one of the TO decay photons in a shower counter.