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This paper introduces a new organization, cognitive-web.org, whose goal is to make cognitive tests available on the internet, and thereby to provide users with a "mental health baseline" against which to assess their cognitive function over time. These tests will provide information about changes in cognitive function during normal aging and in dementia.

A study is made of how decoys of different levels of sophistication can defeat theater missile defense radars. In particular we describe an active decoy system consisting of transponders, located on both decoy and warhead, which are “deceptive jammers,” producing returns to the radars that are identical for both decoy and warhead. The signals override the normal signals reflected from warhead or decoy. The method depends only on knowledge of electromagnetic theory and requires no knowledge of “classified” material. It capitalizes on special properties of readily available “frequency independent” antennas. Such decoys can defeat the presently planned THAAD ABM system.

We study nuclear structure effects on the transparency in high transverse momentum $(p,2p)$ and $(e,e'p)$ reactions. We show that in the DWIA-eikonal approximation, even when correlations are included, one can get a factorized expression for the transparency. This depends only on the average nucleon density $\rho(r)$ and a correlation function. We develop a technique to include correlations in a Monte-Carlo Glauber type calculation. We compare calculations of $T$ using the eikonal formalism and a continuous density, with a Monte Carlo method based on discrete nucleons.

The establishment of postlaunch controls on nuclear‐armed missiles, which would enable a country to destroy its missiles in flight in case of an accidental or unauthorized launch, would add another safeguard to the control of nuclear weapons. A system of postlaunch control could be made secure against attempts by another country to use the system to destroy authorized launches in flight.

Data on 120 GeV photoproduction ofJ/Ψ's in nuclear targets are re-examined to extract the absorption cross section forJ/Ψ's in high energy collisions with nucleons. We find σa=6.6±2.2 mb in contrast with an earlier estimate of 1–2 mb. Comparison of low and high energy data on photon producedJ/Ψ's thus no longer show possible evidence for observable effects of color screening. Examination of representative data on the Feynmanx distributions ofJ/Ψ production by hadrons demonstrates how to extract both the total inelasticJ/Ψ-nucleon cross section and the partial cross section into open charm. We find that the data is inconsistent with any significant contribution from color screening.

The 1971 Accidents Agreement between the US and the USSR specifies what each country must do in the event of an accidental or unauthorized launch of a nuclear weapon. Logic and technology are not enough to bring about a major change in the way nuclear weapons are handled. It is well to recall that the technology was in place for a decade, and the US nuclear arsenal had risen to 20,000, before John F. Kennedy decided to install pre-launch controls in the form of permissive action links (PALs) on US nuclear weapons. The Bush administration must generate the will to move toward post-launch controls. It can begin by convening the proposed committees to study and report back on post-launch controls. Although the armed services committees of both houses have neglected this subject in the past, there is some recent sign of recognition of the need to devote attention to this increasingly important feature of nuclear weapon safety. The little-known Accidents Agreement of 1971 was far-sighted, and its implementation must be guaranteed. 6 refs.

All measured Feynman x_f distributions of the ratio, R, of j_psi production in nuclei relative to production on protons fall off with x_f. They show [2] that absorption of charmonium cannot be the only source of j_psi suppression and that energy loss of the constituents of the incident proton prior to the j_psi production, because of the exponential sqrt(s) dependence of the charmonium cross section, should not be neglected. Including the effects of initial state energy loss we find that the latest measured Pb-Pb j_psi cross sections do not provide any evidence for deconfinement., Comment: 9 pages, 2 figures, additional material, accepted by Physics Letters

The importance of reporting correlations among side effects is examined using studies of BPH drugs as examples. The special relation of placebo effects in studying side-effects of drugs, as opposed to their efficacies, is introduced, and the need for special new controls is presented.

Recently measured [ital Q][sup 2] and [ital A] dependences of nuclear transparency ([ital T]) in [ital e],[ital e][sup [prime]][ital p] interactions are in agreement with theoretical predictions based on a Glauber theory which incorporates the internucleon spatial correlations.

Published data on the safety and efficacy of finasteride in the treatment of benign prostatic hyperplasia are studied and compared with published conclusions. The need for publishing correlation studies of both the benefits and side-effects, to allow for informed physician and patient decisions, is detailed. © 1995 Wiley-Liss, Inc.

Measurement of the differential cross sections for the 180° production of protons from 6 Li, C, and Ta by protons (600 MeV), duetrons (361 MeV), and α-particles (726 MeV) have been carried out. The results are shown to be in accord with “quasi-two body scaling”. The data follow a structure function distribution G(k)≈ e − k k 0 up to internal nucleon momenta, k = 1.3 GeV/ c . The measurements in 6 Li extend the validity of this functional form up to values of k close to the elastic scattering limit.

Bose-Einstein correlations between pions produced in the central region of rapidity in αα, pp and p p interactions have been studied at the ISR. The parameters r and τ c -often interpreted as the radius and depth of the π-emitting region - are found to be independent of incident particle type but to depend on the mean charged multiplicity. In high multiplicity events, the pions appear to originate from a larger space-time region.

We have measured the production of one and two large transverse momentum hadrons in pp and pp interactions in the range 2 < pT < 6 GeV/c for the central rapidity region |y| < 0.9 at s = 63 and 31 GeV. No statistically significant difference between pp and pp collisions is observed. The results are in accordance with lowest order QCS perturbative calculations and rule out a large contribution of Constituent Interchange Model (CIM), di-quark of quark-fusion subprocesses in this kinematic range.

This paper reports measurements of the analyzing power, A/sub y/, in the production of both ''backward'' protons and forward (quasifree scattering) protons in the reaction p + A ..-->.. p + X, using 800-MeV polarized protons. For the backward protons the measurements show large negative A-dependent values of A/sub y/ at low momenta, changing to large positive values at high momenta; in the quasielastic region, A/sub y/ is large and positive, is smaller than A/sub y/ measured in hydrogen, and decreases with increasing A.

We have analyzed 25 000 ${K}_{e3}$ decays, reconstructed to the center of mass by measurement of the ${{K}_{L}}^{0}$ momentum from time of flight and measurement of the $\ensuremath{\pi}$ and $e$ momenta with a spark-chamber-magnet spectrometer. Using the linear parametrization of the vector form factor ${f}_{+}({q}^{2})=1+{\ensuremath{\lambda}}_{+}(\frac{{q}^{2}}{{{m}_{\ensuremath{\pi}}}^{2}})$ we find ${\ensuremath{\lambda}}_{+}=0.0270\ifmmode\pm\else\textpm\fi{}0.0028$. Upper limits for the scalar (${f}_{s}$) and tensor (${f}_{t}$) form factors at the 68% confidence level are $\frac{{f}_{s}}{{f}_{+}}l0.04$, $\frac{{f}_{t}}{{f}_{+}}l0.23$, corresponding to intensity ratios $\frac{{I}_{s}}{{I}_{v}}=0.3%$ and $\frac{{I}_{t}}{{I}_{v}}l0.4%$.

The detailed shape of events triggered by a 1.7 sr hadron calorimeter is studied using charged track information in the Axial Field Spectrometer at the CERN ISR. With increasing transverse energy (ET) a large fraction of the events are seen to have a limited transverse momentum relative to the trigger direction. A comparison of the circularity of the events with a prediction of a QCD-motivated Monte Carlo model shows that at high ET the events originate predominantly from two-constituent scattering.

Measurements of the invariant cross sections for the reaction $p(400 \mathrm{GeV})+(^{6}\mathrm{Li}, \mathrm{B}\mathrm{e},\phantom{\rule{0ex}{0ex}}\mathrm{C},\phantom{\rule{0ex}{0ex}}\mathrm{A}\mathrm{l},\phantom{\rule{0ex}{0ex}}\mathrm{C}\mathrm{u},\phantom{\rule{0ex}{0ex}}\mathrm{T}\mathrm{a})\ensuremath{\rightarrow}({\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}, {K}^{\ifmmode\pm\else\textpm\fi{}})+X$ at laboratory angles from 70\ifmmode^\circ\else\textdegree\fi{} to 160\ifmmode^\circ\else\textdegree\fi{} are reported. Upper limits for $\overline{p}$ production are given. Comparisons of the data are made using several scaling variables.NUCLEAR REACTIONS Inclusive cross section; 400 GeV incident protons; $^{6}\mathrm{Li}$, Be, C, Al, Cu, Ta targets; production of $\ensuremath{\pi}$, $K$, and $\overline{p}$; lab angles 70\ifmmode^\circ\else\textdegree\fi{} to 160\ifmmode^\circ\else\textdegree\fi{}.

Recent measurements of high energy inclusive cross sections in $^{6}\mathrm{Li}$, close to the elastic limit, allow for experimental verification of the "coherent recoil" postulate of "quasi-two-body scaling." Theoretical arguments for the dominance of coherent recoil up to internal nucleon momenta $k\ensuremath{\simeq}1.2 \frac{\mathrm{GeV}}{c}$ are presented, along with a new "derivation" of the relationship between quasi-two-body scaling and an "effective" ground state momentum distribution. A possible relationship between inclusive and elastic cross sections is explored.[NUCLEAR REACTIONS Quasi-two-body scaling, "effective" momentum distributions.]

The production of direct photons has been measured relative to π 0 's in the rapidity range 2.00 y s = 63 GeV at the CERN Intersecting Storage Rings. The γ/π 0 ratio increases from ⪅2% at p T = 1.5 GeV/ c to ∼8% at p T = 4.25 GeV/ c , similar to the value observed near 90°. The results indicate no strong enhancement of single-photon production due to quark bremsstrahlung in this kinematic region.

Using the present knowledge of p-p data and its representation by the ISAJET minimum-bias-event structure, we calculate the invariant mass and the energy loss of an excited proton traversing nuclear matter and, from this, its rapidity loss, both before and after hadronization. We find the difference between the leading proton rapidity loss in pPb interactions and that in p-p interactions, integrated over all p t , to be 0.29.

The interaction of a ’’scalar’’ charge es (even under T) and a ’’pseudoscalar’’ charge ep (odd under T) is investigated in the framework of classical mechanics. We show that the most general force consistent with the conservation of linear momentum and angular momentum is F=esep(r×v)/cr3, where c is a constant. This is just Dirac’s force between electric and magnetic charges. No use is made of Maxwell’s equations. With the single assumption that the forces can be expressed in terms of vector and axial vector fields, we can derive exact expressions for the fields and then for the forces between two scalar and two pseudoscalar charges. These forces, in turn, are found to be identical with those of Coulomb and Biot–Savart. The theory retains P conservation and T invariance in both Newton’s laws of motion and the expressions for the fields.

Production of rho ^{0}, K*^{0}, and phi have been measured in proton-proton collisions at the CERN Intersecting Storage Rings (ISR) at low p/sub T/ in the central region. The transverse mass spectra are well described by exp (-a mu /sub T/), with a=-6.4+or-0.2 GeV/sup -1/. The cross sections for d sigma /dy mod /sub y=0/ are 6.5+or-0.8+or-1.2 mb for rho ^{0}, 1.9+or-0.3+or-0.3 mb for K*^{0}, 1.9+or-0.3+or-0.3 mb for K*^{0}, and 0.60+or-0.12+or-0.13 mb for phi , where the first error is statistical and the second is systematic.

Calorimeter measurements of dσ de t for pp, dd, pα , and αα collisions at S nn =31.5 GeV are presented for the pseudorapidity interval | η cm | ⩽ 0.7, extending over eight decades to E t ⩾ 30 GeV. The data are compared with models that predict nuclear cross sections directly from pp data, under the assumption of independent nucleon scatters.

Measurements of charged particle multiplicity distributions in the central rapidity region in p-p and p-α, and α-α collisions are reported. They are better fitted to the “wounded nucleon” than to the “gluon string” model. The average transverse momenta, for all three reactions, are identical (and almost independent of multiplicity) up to very high multiplicities.

We report the negative result of a search for the decay products of long- lived particles having lifetimes in the range 50 milliseconds to 10 hours. The upper limit for the ''cross section for production and capture'' of such particles in a 33-cm aluminum target irradiated with 400-GeV protons is set at less than 10$sup -36$ cm$sup 2$. (AIP)

The production of inclusive prompt positrons in pp collisions at √ s = 63 GeV and θ cm = 90° has been measured over the p T interval 0.08 T GeV c . The e / π ratio rises from ∼ 2 × 10 −4 at p T = 0.9 GeV c to ∼ 1 × 10 −3 at p T = 0.1 GeV c . This is a factor of 6 higher than would be expected from the sum of hadronic bremsstrahlung and the semileptonic decay of charm.

Measurements of the invariant cross sections for the reaction $p(400 \mathrm{GeV})+(^{6}\mathrm{Li}, \mathrm{B}\mathrm{e},\phantom{\rule{0ex}{0ex}}\mathrm{C},\phantom{\rule{0ex}{0ex}}\mathrm{A}\mathrm{l},\phantom{\rule{0ex}{0ex}}\mathrm{C}\mathrm{u},\phantom{\rule{0ex}{0ex}}\mathrm{T}\mathrm{a})\ensuremath{\rightarrow}(d, t, ^{3}\mathrm{He}, ^{4}\mathrm{He})+X$ at laboratory angles of 70, 90, 118, 137, and 160\ifmmode^\circ\else\textdegree\fi{} are reported. Comparisons are made using several scaling variables.NUCLEAR REACTIONS Inclusive cross section; 400 GeV incident protons; $^{6}\mathrm{Li}$, Be, C, Al, Cu, Ta targets; production of $d$, $t$, $^{3}\mathrm{He}$, $^{4}\mathrm{He}$; Lab angles 70\ifmmode^\circ\else\textdegree\fi{}, 90\ifmmode^\circ\else\textdegree\fi{}, 118\ifmmode^\circ\else\textdegree\fi{}, 137\ifmmode^\circ\else\textdegree\fi{}, and 160\ifmmode^\circ\else\textdegree\fi{}.

(Being a personal account of adventures in Moscow, meetings with Andrei Sakharov, gossip on Aeroflot 317, Gorbachev at the Kremlin, a Saturday night seminar with refuseniks, and the Scientists' Forum.)

The differential cross section for production of jets in pp interactions at y = 0 and p T from 6–12 GeV/ c has been measured at √ s = 45 GeV at the CERN Intersecting Storage Rings and compared with a previous measurement at √ s = 63 GeV. The data were obtained using a 2.1 sr hadron calorimeter which was triggered on transverse energy. The energy dependence of the jet cross section is well described by (1− x T ) m p T − n , with m = 10.6±1.0 and n = 5.3±0.2. The results are in good agreement with predictions obtained from a QCD-motivated model.

The momentum dependence, at fixed pion angles of 180 and 155\ifmmode^\circ\else\textdegree\fi{}, of inclusive pion production reactions has been obtained for 600 MeV protons and 175 MeV/nucleon $\ensuremath{\alpha}$ particles and deuterons on $^{6}\mathrm{Li}$, C, Co, and Ta. The spectra obtained all fall off exponentially with increasing pion momentum, the slope being about 30 MeV/c independent of either target or projectile nature. The data are examined from the point of view of quasi-two-body scaling, a reaction description discussed recently which suggests that ${q}_{min}$, the minimum nuclear recoil momentum possible kinematically, is the proper scaling variable. When plotted versus ${q}_{min}$, all data presented here keep their exponential shape, but the slope becomes 70 MeV/c, i.e., nearly the same as obtained for proton production by the same selection of beam projectiles and energies. It is concluded that the same functional of the target momentum space wave function is revealed by quasi-two-body scaling in inclusive pion production experiments, as in inclusive proton and light-fragment production experiments. Finally, the results of a Monte Carlo calculation of pion spectra based on a single $\mathrm{NN}\ensuremath{\rightarrow}\ensuremath{\pi}\mathrm{NN}$ interaction and taking into account the internal motion of the nucleons in target and projectile are presented. The shape and cross sections are accounted for when effective momentum densities of exponential forms are used; the slope constants necessary are compatible with the ones obtained in quasi-two-body scaling. Using the ground state momentum density of an independent particle shell model produces pion spectra which fall off too rapidly. Furthermore, the Monte Carlo calculation reveals kinematical features of the reaction, which help explain why quasi-two-body scaling works for pion production.

We have measured the production of direct photons, π 0 's, and η's in p p and pp collisions at √ s =53 GeV in the range 2≈ p T ≈6 GeV/ c for the central rapidity region | y | 0.4. No statistically significant difference between pp and pp interactions is observed.

We study the production of identified charged particles in pp collisions at a c.m. energy of 63 GeV in events with an identified high-pT trigger particle. The measurements were performed at the CERN Intersecting Storage Rings using the Axial Field Spectrometer. Production ratios are presented as a function of pT in the range 2.5 to 8 GeV/c.

We have studied the inclusive production of the hadrons π±, K±, p, p , Λ, Λ , ρ and ⋉ in the central region at the ISR s = 53 GeV , in both pp and p p collisions. Differences are observed only for K±, p, and p production. We then study also correlations between low-pT pp and p p pairs in the two types of collisions, separating the contribution from baryon pair production and from the incident particles (stopping protons). We observe a positive correlation between two stopping protons; between the production of two pairs, and between a stopping proton and a pair production, there are negative correlations.

The inclusive cross sections, measured up to large values of effective mass ($\ensuremath{\equiv}\frac{{q}^{2}}{2\ensuremath{\nu}}$), are well fitted by $\frac{d\ensuremath{\sigma}}{{d}^{3}p}={B}_{x}\mathrm{exp}(\ensuremath{-}\frac{{\ensuremath{\alpha}}_{x}{p}^{2}}{2{m}_{x}})$. Values of ${B}_{x}$ and ${\ensuremath{\alpha}}_{x}$ are given for Be, C, Cu, and Ta at the incident proton energy of 600 MeV and for Ag, Ta, and Pt at 800 MeV. Extremely large $\frac{d}{p}$ and $\frac{t}{p}$ ratios and large $A$ and ${q}^{2}$ dependences of the relative cross sections are observed.

Calorimeters downstream of the intersection of pα and αα beams in the ISR have been used to study the hadronization of excited nucleons. These data extend and support the conclusions from previous studies of the A-dependence of particle multiplicities in ultrarelativistic p-nucleus collisions, which provided evidence that the proton hadronizes outside the nuclear volume.

Analysis of the ratios of nuclear to hadronic transverse-energy spectra and of central particle production versus numbers of participant nucleons, shows that models of low-p/sub t/ particle production not incorporating ''energy conservation'' provide good fits to the data at low E/sub t/ or low A (A = 4) but disagree strongly with the data at large E/sub t/ and large A (A> or =27), where the measurements are sensitive to large numbers of successive scatters.

We present a method of calculating the energy loss of an “excited” hadron at each interaction in its passage through nuclear matter, which leads naturally to an energy conserving wounded nucleon model. Its input is pp data, as summarized in the “beam-jet”, minimum bias, ISAJET formulation of F. Paige. It appears to reproduce, simultaneously, and without adjustable parameters, all measured features of ultrarelativistic p-nuclear interactions where “rescattering” and “cascading” can be neglected. We find that the rapidity loss of the leading proton is considerably smaller than previous estimates. In addition we discuss and demonstrate rescatterings in heavy nuclei that affect the transverse energy dependence of nuclear cross sections.

Events with a large transverse energy in a calorimeter with full azimuthal coverage and |y

Impact parameter correlations are shown to produce a rise in the e / π ratio with associated multiplicity in the production of pions accompanying low p 1 prompt positrons. The explicit multiplicity dependence is extracted from the data and compared with the Bjorken-Weisberg prediction.

The properties of high-ET events produced inpp collisions at\(\sqrt s \)=63 GeV have been studied at the CERN Intersecting Storage Rings. The fragmentation of the jets is found to be very similar to that of jets produced ine+e− annihilation and at the SPS\(p\bar p\) collider. We measure an excess of soft particles compared withe+e− events and this underlying event is found to be sensitive to the trigger. ThepT balance between the jets is measured. The distribution of charges in the jets indicates that a substantial fraction of the jets originate from valence quarks.

The inclusive π0 production cross-section and the η/π0 ratio have been measured inpp collisions at\(\sqrt s = 63 GeV\) at the CERN Intersecting Storage Rings in the rapidity range 2.00

I show that the shapes of the differential cross sections for the "backward" production of high-energy particles ($p, d, t, \dots{}, {\mathrm{B}}^{11}$), by projectiles of various types ($p, d, \ensuremath{\alpha}$), from nuclei of any $A$ (Be,...,U), and for a large range of incident momenta and backward angles, can be related by quasi-two-body kinematics. This permits the direct determination of the shape of the momentum distribution of high-momentum nucleons in nuclear matter. This distribution is shown to be $F(k)=\frac{\mathrm{exp}(\ensuremath{-}\frac{k}{{k}_{0}})}{k}$ over the range 0.4 to 1.5 GeV/c.

Measurements are reported of the analyzing power of deuterium for 0.8 GeV polarized protons covering the inclusive region up to and including elastic p-d scattering for both forward and backward emitted protons.