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A small aperture magnetic spectrometer has been built to study hadron production in 197 Au + 197 Au collisions at the AGS energy of 11.6A GeV/c. It operates in the forward angular range from 6 to 30° with respect to the incident beam axis and covers the mid-rapidity region for heavy particles such as protons. The detector components of the spectrometer system include two time projection chambers, four drift chamber modules and a time-of-flight scintillation counter wall. A few new technologies are implemented in the design of the system to achieve the performance goals. The spectrometer has proved to function properly under the high particle-density environment encountered in experiments with the heavy-ion colliding system. The achieved momentum resolution is 1.3% in r.m.s. for pions at 1 GeV/c and 1.6% for protons at the same momentum. With the time-of-flight resolution of 76 ps in r.m.s., the particle identification momentum limit extends to 4 GeV/c for pions, 3 GeV/c for kaons, 5 GeV/c for protons, and 4.5 GeV/c for anti-protons. The tracking efficiency stays above 86% for tracks up to 5 GeV/c with as many as 10 tracks in the spectrometer aperture.

In previous work, the E802 Collaboration at the BNL-AGS used negative binomial distribution (NBD) fits to charged particle multiplicity distributions from central collisions of {sup 16}O+Cu at 14.6A GeV/c to derive the two-particle short-range rapidity correlation length and strength. These turned out to be much shorter and weaker than the values for hadron collisions, which led to a simple and elegant explanation of intermittency. In the present work, a direct measurement of the two-particle correlation of identified pions in the E802/E859 magnetic spectrometer is performed in the interval 1.5{le}y{le}2.0 for central {sup 28}Si+Au collisions, both in terms of Q{sub inv}={radical}({vert_bar}{rvec q}{vert_bar}{sup 2}{minus}q{sub 0}{sup 2}), where q=p{sub 2}{minus}p{sub 1}=({rvec q},q{sub 0}), and also in terms of {vert_bar}{eta}{sub 2}{minus}{eta}{sub 1}{vert_bar} and {vert_bar}y{sub 2}{minus}y{sub 1}{vert_bar}, where p,{eta}, and {ital y} are the four-momentum, pseudorapidity, and rapidity of the pions. It is demonstrated that the two-pion correlation in rapidity (and pseudorapidity) is entirely due to the Bose-Einstein interference. The directly measured correlation length in both {eta} and {ital y} is {xi}=0.19{plus_minus}0.03 for two {pi}{sup {minus}}, with strength R(0,0){approximately}1{percent}, in agreement with the previous E802 indirect measurements derived from the NBD analysis of intermittency. {copyright} {ital 1997} {ital The American Physical Society}

We report measurements of proton emission at target rapidities for minimum bias and central collisions of 14.6AGeV/c {sup 28}Si with Al, Cu, and Au nuclei as well as minimum bias and central collisions of 11.7AGeV/c {sup 197}Au with Au nuclei. Results for deuteron emission are also reported for the Si+Au reaction. The spectra span the laboratory angular range of 50{degree}{le}{theta}{le}130{degree} and kinetic energy range of 40MeV{le}E{sub kin}{le}225MeV. Inverse slopes of proton spectra and proton dN/d{eta} values in the kinetic energy range 50MeV{le}E{sub kin}{le}110MeV are reported. The inverse slopes are 40{endash}80 MeV for the various systems, generally increasing with increasing pseudorapidity. The dN/d{eta} values for A+A collisions within the restricted kinetic energy interval are compared to those for protons from p+Au in the literature. All pseudorapidity distributions have very similar shapes. The experimental results have been compared to the predictions of the nucleon-nucleon collision models ARC and RQMD. The predictions made by these two models for the distribution of protons at target rapidities are very similar to each other. However, there are significant differences between the model predictions and the experimental results in the details of the spectral slopes and the proton yields for different trigger conditions. {copyright} {ital 1997} {italmore » The American Physical Society}« less

The E-802 Collaboration at the BNL-AGS has measured charged particle multiplicity distributions from central (ZCAL) collisions of {sup 16}O+Cu at 14.6{ital A} GeV/{ital c} as a function of the pseudorapidity interval {delta}{eta}{ge}0.1 in the range 1.2{le}{eta}{le}2.2. The fluctuations of these distributions as a function of the pseudorapidity interval have been studied by the method of normalized factorial moments and also by directly fitting the measurements to negative binomial distributions (NBD). Excellent fits to NBD were obtained in all {delta}{eta} bins, allowing, for the first time, a systematic formulation of the subject of intermittency in terms of distributions to complement the description based on normalized factorial moments. In agreement with all previous measurements of NBD fits to multiplicity distributions in hadron and lepton reactions, the {ital k} parameter of the NBD fit for central {sup 16}O+Cu collisions is found to exhibit an apparently linear increase with the {delta}{eta} interval, albeit with a much steeper slope than for other reactions, and a nonzero intercept, {ital k}(0){ne}0. The evolution of the NBD parameter {ital k}({delta}{eta}) is used to determine the two-particle short-range rapidity correlation length for central {sup 16}O+Cu collisions, {xi}=0.18{plus_minus}0.05, which is much shorter than the value {xi}{similar_to}1--3 for hadron collisions, butmore » this is a quantitative rather than a qualitative difference. These results lead to a simple and elegant explanation of the intermittency formalism, without resort to fractals, for all reactions, which demystifies intermittency---for {sup 16}O+Cu central collisions, intermittency is nothing more than the apparent statistical independence of the multiplicity in small pseudorapidity bins, {delta}{eta}{similar_to}0.2, due to the surprisingly short two-particle rapidity correlation length.« less

Fluctuations in pseudorapidity distributions of charged particles from central collisions of 16 O+Al and 16 O+Cu at 14.6 A GeV/ c are analyzed using scaled factorial moments. A power-law growth of moments with decreasing bin size is observed down to δη ∼ 0.1. About half the measured signal remains after making corrections based on Monte Carlo calculations with Fritiof and GEANT which include γ-conversions, Dalitz decays and detector effects.

The AGS spectrometer experiment E-802 has measured transverse mass spectra for charged hadrons over a wide rapidity interval in Si+Au, Si+Cu, and Si+Al reactions at 14.6A Gev/c. These results are compared for two different trigger conditions: central collisions corresponding to 7% of the inelastic cross section selected on multiplicity of charged particles and peripheral collisions corresponding to roughly 50% of the inelastic cross section selected on high kinetic energy at zero degrees. The invariant spectra are well described by exponentials in transverse mass allowing the extraction of rapidity distributions and inverse slope parameters for each specie emitted in the different reactions.

Measurements of the global transverse energy distributions dσ / dE T and dE T / dη using the new AGS beam of 197 Au at 11.6 A GeV/ c on a Au target, as well as a beam of 28 Si at 14.6 A GeV/ c on Al and Au targets, are presented for a leadglass detector with acceptance 1.3 ≤ η ≤ 2.4 and 0 ≤ φ π . The dσ / dE T spectra are observed to have different shapes for the different systems and simple energy rescaling does not account for the projectile dependence. The Au+Au dσ / dE T spectrum is satisfactorily constructed from the upper edge of Si+Au by the geometric Wounded Projectile Nucleon Model after applying a correction for the beam energy.

We present preliminary results for the emission of target rapidity protons in minimum bias and central 11.7 A.GeV/c Au+Au collisions. The data span the pseudo-rapidity range {vert_bar}{eta}{vert_bar} {le} 0.76 and proton kinetic energy range of 50 {le} E {le} 200 MeV. The slopes of the kinetic energy spectra and dN/d{eta} values for central and minimum bias collisions are strikingly similar. Comparison of the results to results for Si+Au and p+A shows that the shape of the dN/d{eta} distribution is independent of the reaction system or centrality suggesting that the spectator matter does not play a decisive role in determining the shape of the proton distributions at back angles for these systems at AGS energies.

Neutral pi0 and eta spectra have been obtained over a wide transverse momentum range for various centralities of S + Au collisions at 200 GeV/nucleon. The analysis was done of the full statistics of the WA80 experiment at CERN using the two-photon invariant mass spectra. Compared to the previous analysis [1, 2] the pi0 and eta spectra were obntained over an extended p(t) range of 0.2

A phoswich array consisting of 42 ΔE − E scintillator telescopes is described. The array was used for the measurement of charged pions, protons, deuterons and tritons produced near target rapidity in relativistic collisions of 14.6 A GeV/ c 28 Si nuclei with targets ranging in mass from aluminum to gold. The present paper describes the array, its operation and performance, its response to protons, deuterons and tritons, and the means by which the detector has been calibrated. Intrinsic energy resolutions on the order of 2–3% have been obtained.

We show that electron- and proton-impact ionization cross sections for highly stripped heavy ions can be deduced from the projectile-electron-loss cross sections determined by collisions with a ${\mathrm{H}}_{2}$ and a He target. We measure electron loss for 100- and 380-MeV/u ${\mathrm{Au}}^{52+}$, and 405-MeV/u ${\mathrm{U}}^{86+}$ in ${\mathrm{H}}_{2}$ and He targets, and extract the electron- and proton-impact ionization cross sections. Our results are compared with calculations and with channeling experiments.

K + and π + multiplicities have been measured in magnetic spectrometer for Si++ Al, Si+ Cu and Si + Au collisions at 14.6 A GeV/ c incident momentum. The multiplicities were obtained for five different windows of forward kinetic energy as detected in a zero degree calorimeter. The K + / π + multiplicity ratio ranges from ≈9% in peripheral interactions to 19% in central Si+Au. The largest K + / π + ratios are observed for those events for each target that leave the least energy in the zero degree calorimeter and the ratio increases with target mass. The observations suggest that multiple interactions are important in the particle production mechanism.

Recent single-particle inclusive measurements and two-particle correlation data from E802 and its succesor, E859, are presented. The K + / π + ratio observed for collisions of 14.6 A·GeV 28 Si ions on various targets is presented as a function of both forward and transverse energy. Source sizes are determined via interferometry using π + , π − , K + and proton pairs.

Preliminary results are presented for the production of protons in 14.6 A{center dot}GeV/c Si+Al and Si+Au collisions measured by the E859 Phoswich Array at the BNL AGS. The proton data presented cover the laboratory angles of 50--130 degrees and kinetic energies of 40--180 MeV. Slopes and integrated distributions are extracted and comparisons with other experimental data are discussed.

Forward and transverse energy spectra and the correlation between these two global variables have been measured for the interaction of 14.6{ital A} GeV/{ital c} {sup 28}Si ions with {sup 27}Al and {sup 197}Au. The energy in produced particles near midrapidity is observed to be negatively correlated with forward energy. There is minimal target mass dependence of this correlation for peripheral and semicentral interactions (forward energies{gt}80 GeV). However, the fact that transverse energies for more central collisions in Au become increasingly larger than those in Al ({similar to}50% greater in the limit of zero forward energy), provides evidence for multiple interactions of projectile nucleons in the larger target. The experimental results are discussed in terms of calculations based on a model for nucleus-nucleus interactions.

The production of {pi}{sup {plus minus}},{ital K}{sup {plus minus}},{ital p} has been measured in {ital p}+Be and {ital p}+Au collisions for comparison with central Si+Au collisions. The inverse slope parameters {ital T}{sub 0} obtained by an exponential fit to the invariant cross sections in transverse mass are found to be, {ital T}{sub 0}{sup {ital p},}{ital K+},{pi}{sup {pi}}{similar to}140--160 MeV in {ital p}+{ital A} collisions, whereas in central Si+Au collisions, {ital T}{sub 0}{sup {ital p},}{ital K+}{similar to}200--220 MeV {gt}{ital T}{sub 0}{sup {pi}{pi}}{similar to}140--160 MeV at midrapidity. The {pi}{sup {plus minus}} and {ital K}{sup +} distributions are shifted backwards in {ital p}+Au compared with {ital p}+Be. A gradual increase of ({ital dn}/{ital dy}){sub {ital K}}{sup +} per projectile nucleon is observed from {ital p}+Be to {ital p}+Au to central Si+Au collisions, while pions show no significant increase.

The increased particle current demands on both ion source and injection facility by a heavy-ion synchrotron collider are analyzed. Also, the existing injector arrangement and performance for most of the world's fixed-target heavy-ion synchrotrons are compared. At the present time, the Drookhaven relativistic heavy-ion collider (RHIC) requirements for the heaviest ions can be met by an injector with a front end consisting of a negative ion source and electrostatic tandem Van de Graaff accelerator. For the heaviest ions, considerable research and development is necessary on both ECR and EBIS high-charge state ion sources before required particle currents can be met.

The recent availability of 14.6 GeV/c per nucleon 16O and 28Si ions from the Brookhaven National Laboratory Tandem-AGS accelerator facility has prompted the design, construction and operation of a large-solid-angle (25 msr) magnetic spectrometer with particle identification from ∼0.5 to ∼4.7 GeV/c. A small-solid-angle Cherenkov counter complex views the target through the magnet and extends the particle identification up to ∼15 GeV/c. This experiment (E-802) employs event characterization detectors, a charged-particle multiplicity array, a highly segmented lead-glass detector, and a zero degree calorimeter. The facility measures momentum spectra of identified heavy-ion-produced hadrons with high resolution (Δp/p≤0.005) as a function of collision centrality given by triggers from the event characterization detectors. Construction and performance details of the spectrometer components and auxiliary detectors are described.

Semi-inclusive spectra of {pi}{sup {plus minus}}, {ital K}{sup {plus minus}}, and {ital p} have been measured near midrapidity for central collisions of 14.6{ital A}-GeV/{ital c} {sup 28}Si with {sup 197}Au nuclei. The invariant cross sections are all well fit by exponential distributions in transverse mass, within the measured ranges. The {pi} and {ital K} cross sections can also be fit by Boltzmann distributions. From integrated yields, at midrapidity, the kaon/pion yield ratios are (19.2{plus minus}3)% for {ital K}{sup +}/{pi}{sup +} and (3.6{plus minus}0.8)% for {ital K}{sup {minus}}/{pi}{sup {minus}}; the {pi}{sup +}/{pi}{sup {minus}} ratio is 1.00{plus minus}0.04.

In a previous publication [T. Abbott et al., E802 Collaboration, Phys. Rev. C 63, 064602 (2001); 64, 029901(E) (2001)], measurements of the A dependence and pseudorapidity interval $(\ensuremath{\delta}\ensuremath{\eta})$ dependence of midrapidity ${E}_{T}$ distributions in a half-azimuth $(\ensuremath{\Delta}\ensuremath{\varphi}=\ensuremath{\pi})$ electromagnetic calorimeter were presented for $p+\mathrm{Be},$ $p+\mathrm{Au},$ O+Cu, Si+Au, and Au+Au collisions at the BNL-AGS. The validity of the ``nuclear geometry'' characterization versus $\ensuremath{\delta}\ensuremath{\eta}$ was illustrated by plots of the ${E}_{T}(\ensuremath{\delta}\ensuremath{\eta})$ distribution in each $\ensuremath{\delta}\ensuremath{\eta}$ interval in units of the measured $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p+\mathrm{A}\mathrm{u}}$ in the same $\ensuremath{\delta}\ensuremath{\eta}$ interval for $p+\mathrm{Au}$ collisions. These plots, with aperture corrected scale in the physically meaningful units of number of average observed $p+\mathrm{Au}$ collisions, were nearly universal as a function of $\ensuremath{\delta}\ensuremath{\eta},$ confirming that the reaction dynamics for ${E}_{T}$ production at midrapidity at AGS energies is governed by the number of projectile participants and can be well characterized by measurements in apertures as small as $\ensuremath{\Delta}\ensuremath{\varphi}=\ensuremath{\pi},\ensuremath{\delta}\ensuremath{\eta}=0.3.$ A key ingredient in these analyses is the probability ${p}_{0}$ for no signal to be detected in a given aperture $\ensuremath{\delta}\ensuremath{\eta}$ for the fundamental $p+\mathrm{Au}$ collision. In fact the measured $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p+\mathrm{A}\mathrm{u}}$ is biased and the true $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p+\mathrm{A}\mathrm{u}}^{\mathrm{true}}$ for the detector aperture is the measured value times $1\ensuremath{-}{p}_{0}.$ The issues and merits of measuring the ${E}_{T}(\ensuremath{\delta}\ensuremath{\eta})$ distribution in units of $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p+\mathrm{A}\mathrm{u}}$ or $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p+\mathrm{A}\mathrm{u}}^{\mathrm{true}}$ in the same $\ensuremath{\delta}\ensuremath{\eta}$ interval are presented and discussed. This method has application at RHIC, where p-$p$ data could be used as the reference distribution for two participants. The ${E}_{T}$ distributions for $B+A$ collisions, with ${E}_{T}(\ensuremath{\delta}\ensuremath{\eta})$ scale normalized by $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p\ensuremath{-}p}^{\mathrm{true}}$ in the same aperture for $p\ensuremath{-}p$ collisions, would then be given directly in the popular unit ``per participant-pair'' [K. Adcox et al., PHENIX Collaboration, Phys. Rev. Lett. 86, 3500 (2001); I. G. Bearden et al., BRAHMS Collaboration, Phys. Lett. B523, 227 (2001); B. B. Back et al., PHOBOS Collaboration, Phys. Rev. C 65, 031901(R) (2002); C. Adler et al., STAR Collaboration, Phys. Rev. Lett. 89, 202301 (2002)].

Two-pion correlation functions are analyzed at mid-rapidity for three systems (14.6 A-GeV Si+Al, Si+Au, and 11.6 A-GeV Au+Au), seven distinct centrality conditions, and different kT bins in the range 0.1--0.5 GeV/c. Source reference frames are determined from fits to the Yano-Koonin source parameterization. Bertsch-Pratt radius parameters are shown to scale linearly with both number of projectile and total participants as obtained from a Glauber model calculation. A finite emission duration that increases linearly with system/centrality is also reported. The mT dependence of the Bertsch-Pratt radii is measured for the central Si+Au and Au+Au systems. The system/centrality dependence is investigated separately for both high and low mT regions.

Measurements of the A dependence and pseudorapidity interval $(\ensuremath{\delta}\ensuremath{\eta})$ dependence of midrapidity ${E}_{T}$ distributions in a half-azimuth (\ensuremath{\Delta}\ensuremath{\varphi}=\ensuremath{\pi}) electromagnetic calorimeter are presented for $p+\mathrm{Be},$ $p+\mathrm{Au},$ O+Cu, Si+Au, and Au+Au collisions at the BNL-AGS (Alternating-Gradient Synchrotron). The shapes of the upper edges of midrapidity ${E}_{T}$ distributions as a function of the pseudorapidity interval \ensuremath{\delta}\ensuremath{\eta} in the range 0.3 to 1.3, roughly centered at midrapidity, are observed to vary with \ensuremath{\delta}\ensuremath{\eta}, like multiplicity---the upper edges of the distributions flatten as \ensuremath{\delta}\ensuremath{\eta} is reduced. At the typical fixed upper percentiles of ${E}_{T}$ distributions used for nuclear geometry characterization by centrality definition---7 percentile, 4 percentile, 2 percentile, 1 percentile, 0.5 percentile---the effect of this variation in shape on the measured projectile ${A}_{p}$ dependence for ${}^{16}\mathrm{O},$ ${}^{28}\mathrm{Si},$ ${}^{197}$Au projectiles on an Au target is small for the ranges of \ensuremath{\delta}\ensuremath{\eta} and percentile examined. The ${E}_{T}$ distributions for $p+\mathrm{Au}$ and $p+\mathrm{Be}$ change in shape with \ensuremath{\delta}\ensuremath{\eta}; but in each \ensuremath{\delta}\ensuremath{\eta} interval the shapes of the $p+\mathrm{Au}$ and $p+\mathrm{Be}$ distributions remain indentical with each other---a striking confirmation of the absence of multiple-collision effects at midrapidity at AGS energies. The validity of the nuclear geometry characterization versus \ensuremath{\delta}\ensuremath{\eta} is illustrated by plots of the ${E}_{T}(\ensuremath{\delta}\ensuremath{\eta})$ distribution in each \ensuremath{\delta}\ensuremath{\eta} interval in units of the measured $〈{E}_{T}(\ensuremath{\delta}\ensuremath{\eta}){〉}_{p+\mathrm{Au}}$ in the same \ensuremath{\delta}\ensuremath{\eta} interval for $p+\mathrm{Au}$ collisions. These plots, in the physically meaningful units of ``number of average $p+\mathrm{Au}$ collisions,'' are nearly universal as a function of \ensuremath{\delta}\ensuremath{\eta}, confirming that the reaction dynamics for ${E}_{T}$ production at midrapidity at AGS energies is governed by the number of projectile participants and can be well characterized by measurements in apertures as small as \ensuremath{\Delta}\ensuremath{\varphi}=\ensuremath{\pi}, \ensuremath{\delta}\ensuremath{\eta}=0.3.

Charged kaon production has been measured in Si+Al and Si+Au collisions at 14.6 A GeV/c, and Au+Au collisions at 11.1 A GeV/c by Experiments 859 and 866 (the E--802 Collaboration) at the BNL AGS. Invariant transverse mass spectra and rapidity distributions for both K+ and K- are presented. The centrality dependence of rapidity-integrated kaon yields is studied. Strangeness enhancement is observed as an increase in the slope of the kaon yield with the total number of participants as well as the yield per participant. The enhancement starts with peripheral Si+Al and Si+Au collisions (relative to N+N) and appears to saturate for a moderate number of participating nucleons in Si+Au collisions. It is also observed to increase slowly with centrality in Au+Au collisions, to a level in the most central Au+Au collisions that is greater than that found in central Si+A collisions. The enhancement factor for $K^+$ production are 3.0 +-0.2(stat.) +-0.4(syst.) and 4.0 +-0.3(stat.) +-0.5(syst.), respectively, for the most central 7% Si+Au collisions and the most central 4% Au+Au collisions relative to N+N at the correponding beam energy., Comment: RevTeX style, 18 pages, 9 figures, 1 table. Minor changes. Phys. Rev. C in press

Peyronie's disease is an ill-understood condition afflicting men in their 40s with the reported age ranging from 18 to 68 years. It is characterized by a plaque in the tunica albuginea which leads to penile deformity making sexual intercourse difficult if not impossible and is often accompanied by severe pain upon erection in the early stage; erectile dysfunction is present in about 2% of cases. Diagnosis rests upon medical history, clinical examination with plaque palpation and autophotography in two planes. These diagnostic steps are not plaque-specific and therefore we wanted to assess which imaging modalities would allow for an objective determination of the plaque status.We evaluated 20 patients with Peyronie's disease. All patients underwent clinical examination including autophotography and the subsequent use of the following imaging techniques: (1) ultrasound (US) using a 7.5-MHz transducer with a profile for semiquantitative density analysis; (2) X-ray in mammography technique in two planes; (3) computerized tomography (CT) with a density profile, and (4) magnetic resonance imaging (NMR).(1) Degree of deviation: Penile deviation ranged from 15 degrees to 63 degrees. It was best assessed using radiography in mammography technique reflecting the results obtained by autophotography. (2) Calcifications: Plaque calcifications were seen in 12 patients, 8 had no calcifications but thickening of the tunica albuginea only, 2 also had a fibrosis of the corpus cavernosum distant to the plaque. Calcifications were visualized using ultrasound sonography (12/12), radiographically (12/12), CT (12/12), NMR (9/12). Thickening of the tunica albuginea only was visualized using ultrasound sonography (7/8), radiographically (0/8), CT (2/8), NMR (6/8). (3) Morphological pattern in ultrasound: Three distinct patterns could be detected: (type 1) the plaque appeared as a thickening of the tunica albuginea without acoustic shadowing and only minimal density increase in the histogram profile; (type 2) moderately calcified plaque with typical ultrasound shadow but minimal density increase in the density profile; (type 3) severely calcified plaque with typical acoustic shadowing and density increase in the histogram profile. (4) Plaque inflammation: Only NMR with gadolinium DTPA showed periplaque inflammation.High-resolution ultrasound sonography is the best imaging modality in assessment of plaques. NMR is the modality of choice to monitor the inflamed plaque. X-ray in mammography technique and CT are not necessary in daily routine.

Peyronie's disease is characterized by an acquired penile deviation that may lead to severe penile deformity. It is refractory to most conservative therapy, and surgical correction is therefore the treatment of choice once the disease process has come to a halt. Basic science, as well as our first clinical results on the use of interferons (IFNs), have been promising, suggesting a beneficial effect in the early noncalcified disease stage.From July 1994 to October 1995, 30 patients suffering from early Peyronie's disease were treated with three local injections of 3 million units of IFN-alpha 2b each into the plaque(s). The interval between the injections was 1 week. Patients were assessed clinically and ultrasonographically 6 months after the last injection.Peyronie's disease clinically improved in only 1 case, remained stable in 26 patients and worsened in 3. In 7 patients, a total of 10 plaques at different sites were detected. By ultrasonography the treated plaques now showed calcifications in 3 cases, remained unchanged in 26 and could not be detected in 1 case. Of the 10 new plaques, 2 showed calcifications. Side effects (myalgia, fever) were considerable; in 74 of 90 injections, fever38 degrees C occurred, and a total of 8 working days were lost.IFN-alpha 2b, given according to our regimen, is not useful for the treatment of Peyronie's disease in the early stage since the disease progress continues at different sites in about 25% of the patients, and the side effects are untolerable. Our results also demonstrate that local therapy is not indicated in Peyronie's disease.

Recent experimental work has demonstrated that nitric oxide (NO) is the neurotransmitter responsible for cavernous smooth muscle relaxation. Different studies on the performance of the direct NO-donor SIN-1 (linsidomine chlorhydrate) in patients with erectile dysfunction have come to conflicting results. We have performed a double-blind cross over trial in 40 patients with erectile dysfunction of mixed etiology comparing SIN-1, SIN-1 plus the alpha-blocker Urapidil, and prostaglandin E1 (PGE1) in order to determine the effectiveness of SIN-1. PGE1 achieved the best response, the combination of SIN-1 and Urapidil performed slightly, statistically insignificantly poorer with significantly increased side effects. SIN-1 alone performed statistically significantly (p0.0068) worse. SIN-1 is not a useful alternative to PGE1. The combination of SIN-1 and Urapidil performs equally as good as PGE1 but cannot be recommended due to intolerable side effects.

We report on two cases of primary male infertility attributable to mixed gonadal dysgenesis. In one case the diagnosis was made when the patient was 30 years old; in the other, the 44-year-old patient had been evaluated 4 years before for erectile dysfunction, which had been treated with a penile prosthesis without the diagnosis being made. These two cases are life following exceptional in that the diagnosis was made in adult-life following an uncomplicated male adolescence.

Recent experimental work has demonstrated that nitric oxide (NO) is the neurotransmitter responsible for cavernous smooth muscle relaxation. Different studies on the performance of the direct NO donor linsidomine chlorhydrate (SIN-1) in patients with erectile dysfunction have had conflicting results. We performed a single-blind cross-over trial in 20 patients with erectile dysfunction of mixed etiology comparing prostaglandin E1 (PGE1) to SIN-1 at two different dosages (1 and 2 mg, respectively) in order to determine the effectiveness of SIN-1. PGE1 always achieved the best response, SIN-1 performed statistically significantly poorer irrespective of the dosage used. There were only a few side effects with no significant difference. SIN-1 is not a useful alternative to PGE1 in the treatment of erectile dysfunction.

Antiproton production cross sections have been measured in minimum bias [ital p]+Be, [ital p]+Al, [ital p]+Cu, and [ital p]+Au collisions at 14.6 GeV/[ital c] with the E-802 spectrometer at the Brookhaven Alternating Gradient Synchrotron. The antiproton multiplicity at laboratory rapidities 1.0 to 1.6 shows almost no dependence upon the target mass. The [ital [bar p]] production for [ital p]+Be is somewhat lower than an estimation based upon 19--24 GeV/[ital c] [ital p]+[ital p] data. In this rapidity interval the antiproton yield scales by a factor of 28[plus minus]6 from [ital p]+Au to central Si+Au collisions.

Experimental particle yield ratios from 14.6[ital A]-GeV/[ital c][sup 28]Si interactions with nuclei at intermediate impact parameters are correlated with the orientation of the transverse momentum of projectile fragments. The [pi][sup [plus minus]]/[ital p] ratio increases and the ([ital d]+[ital t])/[ital p] ratio decreases when fragments are deflected toward the observing spectrometer. Asymmetries are confined to the target rapidity region. Assuming a spectator participant model, these results suggest the presence of significant rescattering of particles with dependences on the collision geometry.

The E802 Spectrometer at the Brookhaven Alternating Gradient Synchrotron has been used to measure the correlation in relative momentum between like-sign pions emitted in central Si + Al and Si + Au collisions at 14.6A GeV/c. Data are presented in terms of the correlation function for both identified pi(-) and pi(+) pairs near the nucleon-nucleon center-of-mass rapidity. All parametrizations of the correlation function are consistent with a spherically symmetric source of rms radius 3.5 +/- 0.4 fm and lifetime fm/c.

Particle production in proton-induced reactions at 14.6 GeV/{ital c} on Be, Al, Cu, and Au targets has been systematically studied using the E-802 spectrometer at the BNL-Alternating Gradient Synchrotron. Particles are measured in the angular range from 5{degree} to 58{degree} and identified up to momenta of 5, 3.5, and 8 GeV/{ital c} for pions, kaons, and protons, respectively. Mechanisms for particle production are discussed in comparison with heavy-ion-induced reactions at the same incident energy per nucleon.

Production of light particles (π±,K ±,p) has been measured in both Si+A and p+A collisions. Several interesting features have been observed, among which are: the enhanced K +/π+ ratio and the larger 〈m t 〉 for K + and proton. Comparisons between ≊pp, pA and SiA collisions are discussed.

In ion-atom collisions where the projectile is ionized, target electrons act not only coherently by screening the target nucleus but they may also act incoherently by directly ejecting a projectile electron. This electron-electron interaction should be relatively most important for targets that have a low nuclear charge, since the cross section for a neutral target is roughly proportional to ${\mathit{Z}}_{\mathit{t}}^{2}$+${\mathit{Z}}_{\mathit{t}}$, where ${\mathit{Z}}_{\mathit{t}}^{2}$ is the contribution due to the target nucleus and ${\mathit{Z}}_{\mathit{t}}$ comes from the target electrons. In order to investigate the electron-electron interaction, we have measured and calculated cross sections for ${\mathrm{Li}}^{2+}$, ${\mathrm{C}}^{5+}$, and ${\mathrm{O}}^{7+}$ on ${\mathrm{H}}_{2}$ and He, ${\mathrm{Au}}^{52+}$ on ${\mathrm{H}}_{2}$, He, C, and ${\mathrm{N}}_{2}$, ${\mathrm{Au}}^{75+}$ on ${\mathrm{H}}_{2}$ and ${\mathrm{N}}_{2}$, ${\mathrm{U}}^{86+}$ on ${\mathrm{H}}_{2}$ and He, and ${\mathrm{U}}^{90+}$ on ${\mathrm{H}}_{2}$. The collision energies range from 0.75 to 405 MeV/nucleon. The calculations have been performed in the plane-wave Born approximation. We demonstrate that for energies where the target electrons have sufficient kinetic energy in the projectile frame to ionize the projectile, the electron-electron interaction can lead to a significant increase in the total electron-loss cross section.

The charge state dependence of channeled ion energy loss has been determined for a series of ions ranging from fluorine to chlorine along the $〈110〉$ direction in a silicon crystal. Energy losses for both bare ions and ions partially clothed with bound electrons at $\frac{E}{A}\ensuremath{\cong}3$ MeV/amu have been measured. The energy-loss rate for bare ions follows a strict ${Z}_{1}^{2}$ scaling and agrees reasonably well with quantal perturbation calculations without the need for polarization or Bloch corrections. An explanation for this result is discussed. The clothed-ion energy losses appear to demonstrate screening effects that agree qualitatively with simple estimates. The angular dependence of the observed energy-loss effects is also presented.

Single-Event Upset (SEU) response of a bipolar low-power Schottky-diode-clamped TTL static RAM has been observed using Br ions in the 100-240 MeV energy range and 0 ions in the 20-100 MeV range. These data complete the experimental verification of circuit-simulation SEU modeling for this device. The threshold for onset of SEU has been observed by the variation of energy, ion species and angle of incidence. The results obtained from the computer circuit-simulation modeling and experimental model verification demonstrate a viable methodology for modeling SEU in bipolar integrated circuits.

Data have been obtained for the /sup 35/Cl + /sup 27/Al system at E/sub Cl/(lab) = 170 MeV in which the energy and mass of one particle is measured in coincidence with the energy of a second particle. These coincidence measurements indicate a two-body final state with kinetic energies corresponding to the Coulomb separation energy of the two fragments. The mass distribution of the two correlated fragments is symmetric about half the mass of the compound system. Such data is characteristic of a fission-like process. Similar fission-like cross sections are not observed in data obtained for this system at incident energies up to 145.6 MeV. The competition between particle evaporation and fission, assuming a rotating liquid drop fission barrier, has been calculated using the code ALICE. Such calculations are consistent with the present data. 4 figures.

We show that in relativistic heavy-ion collisions the independent-electron model can be used to predict cross sections for multiple inner-shell ionization in a single collision. Charge distributions of 430- and 955-MeV/amu U/sup 90+/, U/sup 89+/, U/sup 83+/, and U/sup 68+/ beams emerging from thin solid targets were used to obtain single- and multiple-electron stripping cross sections. The probabilities of stripping electrons from the K, L, or M shells were calculated using the semiclassical approximation and Dirac hydrogenic wave functions. The data generally agree with theory. An influence of the Auger effect is seen in U/sup 68+/ collisions.

The main features of the six North American MP tandem Van de Graaff accelerators are summarized as well as some of their main performance characteristics. The latest accelerator-related studies, developments and improvements are described for each facility. Ongoing and proposed future developments at some of these laboratories are briefly discussed.

Evaporation residues of reactions between /sup 24/ /sup 25/ /sup 26/Mg, /sup 27/Al, and /sup 28/Si as targets and 100--170-MeV /sup 35/Cl and 130 MeV /sup 32/S beams and also between /sup 28/Si and 117.5 MeV /sup 28/Si ions were measured at small forward angles by using a time-of-flight telescope. The mass distributions of the products show a complex structure, which is shown to vary smoothly with beam energy and target mass. A dominant decay mode of the compound nucleus can be assigned to each residue mass by using the shape of the angular distribution. An evaporation model calculation predicts qualitatively the main features of the mass distributions.

The Cherenkov Complex system (CC-system) in the E-802 experiment at AGS was successfully operated in the heavy ion running at AGS. Brief description of the system is given. Preliminarily obtained particle spectra for pions, Kaons, and protons near mid-rapidity region in 14.5 A.GeV Si + Au collisions are presented. The spectra shape and the relative yields are compared with those in p + ‘N’ and p + Au collisions.

Coulomb-exploded fragments of ${\mathrm{C}}_{3}^{+,0,\ensuremath{-}}$, ${\mathrm{C}}_{4}^{\ensuremath{-}}$, ${\mathrm{C}}_{5}^{\ensuremath{-}}$, ${\mathrm{C}}_{6}^{\ensuremath{-}}$, and ${\mathrm{NCO}}^{+,0,\ensuremath{-}}$, following stripping of high-energy molecular ions in a thin carbon foil, were recorded, first in plastic sheet detectors, and in later experiments with a new image-intensifying and digitizing system. All of the ions studied in detail, ${\mathrm{C}}_{3}$ and ${\mathrm{NCO}}^{+,0,\ensuremath{-}}$, appear to be formed in states of high bending excitations perhaps close to the dissociation limit. The intranuclear separations for the ${\mathrm{C}}_{3}$ species were found to be similar to that of normal neutral ${\mathrm{C}}_{3}$, 2.5(1) \AA{}; and for the NCO species, rather small, 2.0(1) \AA{}.