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Radiotherapy with sparsely ionizing photons is a cornerstone of successful cancer treatment. Age at time of exposure to radiation is known to influence biological outcomes for many end points. The effect of dose and age at exposure upon the occurrence of radiogenic cardiovascular disease is poorly understood. The goal of this work was to determine the response of maleWAG/RijCmcr rats at 6 months of age to gamma rays, and at 6 months or 6 weeks of age to X rays, using clinically relevant biomarkers of cardiovascular disease and kidney injury. Overall, there were significant radiation-induced effects on the levels of bicarbonate (P=0.0016), creatinine (P=0.0002), calcium (P = 0.0009), triglycerides (P = 0.0269) and blood urea nitrogen, albumin, protein, AST, alkaline phosphatase, total cholesterol and HDL (all P < 0.0001). Of those variables with a significant radiation-dose effect, there were significant modifications by age at time of exposure for bicarbonate (P = 0.0033), creatinine (P = 0.0015), AST (P = 0.0040), total cholesterol (P = 0.0006) and blood urea nitrogen, calcium, albumin, protein, alkaline phosphatase and HDL (all P < 0.0001). Cardiac perivascular collagen content was significantly increased in rats that were 8.0 Gy X-ray irradiated at 6 weeks of age (P < 0.047) but not at 6 months of age. While systemic blood pressure was elevated in both cohorts after 8.0 Gy X-ray irradiation (compared to agematched sham-irradiated controls), the magnitude of the increase above baseline was greater in the younger rats (P < 0.05). These findings indicate that dose and age at time of irradiation determine the timeline and severity of cardiac and renal injury.

To investigate the shape and confinement effects of the terminal siloxane groups on the self-assembled behavior of molecular arrangements in hydrogen-bonded (H-bonded) bent-core complexes, four H-bonded bent-core complexes S1, P1, C4, and P8 with string-, ring-, and cage-like siloxane termini (i.e., linear siloxane unit −Si–O–Si–O–Si–, cyclic siloxane unit (Si–O)4, and silsesquioxane unit POSS, respectively) were synthesized and investigated. By X-ray diffraction measurements, different types of SmCG (B8) phases and leaning angles were controlled by the shape effect of the string- and cage-like siloxane termini for S1 and P1 (with only one arm of H-bonded bent-core), respectively. In addition, the confinement effect of P1, C4, and P8 (accompanied by increasing the numbers of attached H-bonded bent-core arms) resulted in higher transition temperatures and the diminishing of mesophasic ranges (even the disappearance of mesophase in P8). Moreover, AFM images showed the bilayer smectic CG phases of S1 and P1 ...

Two novel blue phase (BP) reactive monomers M1 and M2 containing a bi-mesogenic core are first reported by introducing two end-attached acrylic spacers with different lengths. Due to the self-assembly of bi-mesogenic cores with the same side-by-side end-attached acrylate spacers in homopolymers P1 and P2, no blue phase could be induced by homopolymerization of M1 and M2. However, by interrupting the self-assembly of bi-mesogenic cores with different side-by-side spacer lengths of copolymers P12, double-twisted cylinders of BPIII could be further extended by copolymerization of M1 and M2 with different molar ratios. With M1 : M2 = 5 : 5 (molar ratio) in both side-chain copolymers P12(soln:5/5) and P12(photo:5/5) rather than binary mixture M1/M2(5/5), the widest BPIII ranges of 5.3 °C and 3.8 °C could be obtained by solution- and photo-polymerization, respectively.

Novel hydrogen-bonded (H-bonded) C60- and Si-based bent-core liquid crystal (LC) complexes containing a bent-shaped proton acceptor and C60- and Si-based single/double armed proton donors were synthesized and mixed to produce hybrid H-bonded LC complexes. The SmCP phases could be introduced in the hybrid LC complexes with a very high C60-based moiety up to 90 mol%. Among our H-bonded LC complexes, the hybrid LC complexes with low amounts of the C60-based moiety (≦24 mol%) possessed the highest spontaneous polarization value (ca. 494 nC cm−2), the widest mesophasic range (40.8 °C) and the lowest saturated electric field (8.8 Vpp μm−1). Under electric fields of modified triangle waveforms, both series of hybrid H-bonded LC complexes displayed an anti-ferroelectric (AF) to a ferroelectric (FE) polar switching as the C60-based moiety increased up to 24–50 mol%. Therefore, the hybrid H-bonded LC complexes containing a broad molar ratio (0–90 mol%) of C60-based moiety revealed a tunable route for the electro-optical applications of C60-based H-bonded liquid crystals.

Three series of supramolecular mono-(i.e., Ru1G1, Ru1G2 and Ru1G3), bis-(i.e., BTRu2G1, BTRu2G2 and BTRu2G3) and tris-(i.e., TPARu3G1, TPARu3G2 and TPARu3G3) Ru-based dendritic complexes were synthesized. Their photophysical and electrochemical properties were investigated. These metallodendritic complexes covered a broad absorption range of 250–750 nm with optical bandgaps of 1.51– 1.86 eV. The energy levels of the metallo-dendrimers can be effectively adjusted not only by different generations of dendritic thiophene arms but also by their p-conjugated core ligands bearing various electron donor (i.e., triphenylamine) and acceptor (i.e., benzothiadiazole) moieties. Due to the donor– acceptor effect, the bis-Ru-based dendrimers containing a benzothiadiazole electron-acceptor core ligand showed the highest power conversion efficiency (PCE) among these three series of metallodendrimers. The tris-Ru-based architecture with a triphenylamine electron-donor core ligand revealed moderate photovoltaic performance. Among the different generations (G1–G3) of dendrimers, the third generation (G3) possessed the highest PCE values in each series of Ru-based dendrimers. Hence, the third generation bis-‘Ru’-based dendrimer BTRu2G3 blended with PC70BM (1 : 3 w/w) showed the highest PCE value of 0.77% (without the aid of additives or annealing), which is the highest efficiency among all bulk hetero-junction (BHJ) solar cells containing metallo-dendrimers reported to date.

In this study, we synthesized two novel 1,3,4-oxadiazole-based bent-core liquid crystals (OXD7*, OXD5B7F*) containing a chiral tail that display broad ranges of the blue phase III (34 and 7 K, respectively); we characterized them using polarized optical microscopy, differential scanning calorimetry, and circular dichroism. The electro-optical responses of both of these liquid crystals are much faster than those of previously reported single-component blue-phase liquid crystals. To optimize its electro-optical performance, we mixed OXD7* (the blue-phase range of which is broader than that of OXD5B7F*) with its analogue OXD6 (at weight ratios of 6:4 and 4:6). We also performed molecular modeling of single-component BPLCs (OXD7* and OXD5B7F*) to analyze the possible parameters affecting their blue phase ranges.

The NASA Space Radiation Laboratory (NSRL) is a multidisciplinary center for space radiation research funded by NASA and located at the Brookhaven National Laboratory (BNL), Upton NY. Operational since 2003, the scope of NSRL is to provide ion beams in support of the NASA Humans in Space program in radiobiology, physics and engineering to measure the risk and ameliorate the effect of radiation in space. Recently, it has also been recognized as the only facility in the U.S. currently capable of contributing to heavy ion radiotherapy research. This work contains a general overview of NSRL structure, capabilities and operation.

In space, astronauts are exposed to radiation fields consisting of energetic protons and high atomic number, high-energy (HZE) particles at very low dose rates or fluences. Under these conditions, it is likely that, in addition to cells in an astronaut's body being traversed by ionizing radiation particles, unirradiated cells can also receive intercellular bystander signals from irradiated cells. Thus this study was designed to determine the dependence of DNA damage induction on dose at very low fluences of charged particles. Novel techniques to quantify particle fluence have been developed at the NASA Space Radiation Biology Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The approach uses a large ionization chamber to visualize the radiation beam coupled with a scintillation counter to measure fluence. This development has allowed us to irradiate cells with 1 GeV/nucleon protons and iron ions at particle fluences as low as 200 particles/cm(2) and quantify biological responses. Our results show an increased fraction of cells with DNA damage in both the irradiated population and bystander cells sharing medium with irradiated cells after low fluences. The fraction of cells with damage, manifest as micronucleus formation and 53BP1 focus induction, is about 2-fold higher than background at doses as low as ∼0.47 mGy iron ions (∼0.02 iron ions/cell) or ∼70 μGy protons (∼2 protons/cell). In the irradiated population, irrespective of radiation type, the fraction of damaged cells is constant from the lowest damaging fluence to about 1 cGy, above which the fraction of damaged cells increases with dose. In the bystander population, the level of damage is the same as in the irradiated population up to 1 cGy, but it does not increase above that plateau level with increasing dose. The data suggest that at fluences of high-energy protons or iron ions less than about 5 cGy, the response in irradiated cell populations may be dominated by the bystander response.

Two kinds of novel conjugated polymers containing 2,7-carbazole, thiophene, and fused-dithienothiophene rings as backbones bearing acid-protected and benzoic acid pendants ( PC1 and PC2 , respectively) were utilized for organic solar cell applications. The absorption spectra of these polymers (in both solutions and solid films) showed an absorption range at 300–580 nm. Furthermore, ZnO nanoparticles were synthesized and surface-modified with pyridyl surfactants ( ZnOpy ) to be ca. 3–4 nm. The pyridyl surfactants of ZnOpy nanoparticles (as electron acceptors to partially replace expensive electron acceptor PCBM) not only induce supramolecular interactions with benzoic acid pendants of polymer PC2 via H-bonds, but also enhance the homogeneous dispersions of ZnOpy nanoparticles in polymer PC2 . Thus, the ternary systems of PC1–PC2 / ZnOpy /PCBM in weight ratios of 1:0.05:1 and 1:0.1:1 were investigated in bulk heterojunction polymer solar cells (PSCs). Under the standard illumination of AM 1.5, 100 mW/cm 2 , the best power conversion efficiency (PCE) of the PSC cell containing a polymer blend of PC2 / ZnOpy /PCBM = 1:0.05:1 reached PCE = 0.55%, with J sc = 2.11 mA/cm 2 , V oc = 0.88 V, and FF = 29.4%.

A series of π-conjugated bis-terpyridyl ligands (M1–M3) bearing various benzodiazole cores and their corresponding main-chain Ru(II) metallo-polymers were designed and synthesized. The formation of metallo-polymers were confirmed by NMR, relative viscosity, and UV-visible titration measurements. The effects of electron donor and acceptor interactions on their thermal, optical, electrochemical, and photovoltaic properties were investigated. Due to the strong intramolecular charge transfer (ICT) interaction and metal to ligand charge transfer (MLCT) in Ru(II)-containing polymers, the absorption spectra covered a broad range of 260–750 nm with the optical band gaps of 1.77–1.63 eV. In addition, due to the broad sensitization areas of the metallo-polymers, their bulk heterojunction (BHJ) solar cell devices containing [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as an electron acceptor exhibited a high short-circuit current (Jsc). An optimum PVC device based on the blended polymer P1:PCBM = 1:1 (w/w) achieved the maximum power conversion efficiency (PCE) value up to 0.45%, with Voc = 0.61 V, Jsc = 2.18 mA cm−2, and FF = 34.1% (under AM 1.5 G 100 mW cm−2), which demonstrated a novel family of conjugated polyelectrolytes with the highest PCE value comparable with BHJ solar cells fabricated from ionic polythiophene and C60.

A series of novel hydrogen-bonded (H-bonded) cross-linking polymers were generated by complexing various proton-donor (H-donor) solar cell dyes containing 3,6- and 2,7-functionalized electron-donating carbazole cores bearing symmetrical thiophene linkers and cyanoacrylic acid termini with a proton-acceptor (H-acceptor) side-chain homopolymer carrying pyridyl pendants (with 1/2 M ratio of H-donor/H-acceptor). The supramolecular H-bonded structures between H-donor dyes and the H-acceptor side-chain polymer were confirmed by FTIR measurements. The effects of the supramolecular architecture on optical, electrochemical, and organic photovoltaic (OPV) properties were investigated. From DFT (density functional theory) calculations, the optimized geometries of organic dyes reflected that the carbazole cores of H-donor dyes were coplanar with the conjugated thiophenes and cyanoacrylic acids, which is essential for strong conjugations across the donor-acceptor units in D1–D4 dyes. Under 100 mW/cm2 of AM 1.5 white-light illumination, bulk heterojunction (BHJ) OPV cell devices containing an active layer of H-bonded polymers (PDFTP/D1–D4) as an electron donor blended with [6,6]-phenyl C61-butyric acid methyl ester (PCBM) as an electron acceptor in a weight ratio of 1:1 were explored. From the preliminary investigations, the OPV device containing 1:1 weight ratio of H-bonded polymer PDFTP/D2 and PCBM showed the best power conversion efficiency (PCE) value of 0.31% with a short-circuit current (Jsc) of 1.9 mA/cm2, an open-circuit voltage (Voc) of 0.55 V, and a fill factor (FF) of 29%, which has a higher PCE value than the corresponding H-donor D2 dye (PCE = 0.15%) or H-acceptor PDFTP homopolymer (PCE = 0.02%) blended with PCBM in 1:1 weight ratio.

The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL) was commissioned in October 2002 and became operational in July 2003. The NSRL was constructed in collaboration with NASA for the purpose of performing space radiation research as part of the NASA space program. The NSRL can accept a wide variety of ions from BNL’s Collider Accelerator Department (CAD) Booster accelerator. These ion beams are extracted from the accelerator with kinetic energies ranging from 0.05 to 3 GeV/nucleon. Many different beam conditions have been produced for experiments at NSRL. The facilities at BNL and the design of the NSRL facility permit a wide variety of beams to be produced with a great degree of flexibility in the delivery of ion beams to experiments. In this report we will describe the facility and its performance over the eight experimental run periods that have taken place since it became operational. We will also describe the current and future capabilities of the NSRL.

Novel supramolecular side-chain polymers were constructed by complexation of proton acceptor (H-acceptor) polymers, i.e., side-chain conjugated polymers P1–P2 containing pyridyl pendants, with low-band-gap proton donor (H-donor) dyes S1–S4 (bearing terminal cyanoacrylic acids) in a proper molar ratio. Besides unique mesomorphic properties confirmed by DSC and XRD results, the H-bonds of supramolecular side-chain structures formed by pyridyl H-acceptors and cyanoacrylic acid H-donors were also confirmed by FTIR measurements. H-donor dyes S1–S4 in solid films exhibited broad absorption peaks located in the range of 471–490 nm with optical band-gaps of 1.99–2.14 eV. Furthermore, H-bonded polymer complexes P1/S1–P1/ S4 and P2/S1–P2/S4 exhibited broad absorption peaks in the range of 440–462 nm with optical band-gaps of 2.11–2.25 eV. Under 100 mW/cm2 of AM 1.5 white-light illumination, the bulk heterojunction polymer solar cell (PSC) devices containing an active layer of H-bonded polymer complexes P1/S1–P1/S4 and P2/S1–P2/S4 (as electron donors) mixed with [6,6]-phenyl C61 butyric acid methyl ester (i.e., PCBM, as an electron acceptor) in the weight ratio of 1:1 were investigated. The PSC device containing H-bonded polymer complex P1/S3 mixed with PCBM (1:1 w/w) gave the best preliminary result with an overall power conversion efficiency (PCE) of 0.50%, a short-circuit current of 3.17 mA/cm2, an open-circuit voltage of 0.47 V, and a fill factor of 34%. VVC 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5998–6013, 2009

We present the first measurements of the double spin asymmetries A N N and A S S at s = 200 GeV , obtained by the PP2PP experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). The data were collected in the four momentum transfer t range 0.01 ⩽ | t | ⩽ 0.03 ( GeV / c ) 2 . The measured asymmetries, which are consistent with zero, allow us to estimate upper limits on the double helicity-flip amplitudes ϕ 2 and ϕ 4 at small | t | as well as on the difference Δ σ T between the total cross sections for transversely polarized protons with antiparallel or parallel spin orientations.

We report on the first measurement of the single spin analyzing power ( A N ) at s = 200 GeV , obtained by the PP2PP experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). Data points were measured in the four momentum transfer t range 0.01 ⩽ | t | ⩽ 0.03 ( GeV / c ) 2 . Our result, averaged over the whole | t | interval is about one standard deviation above the calculation, which uses interference between electromagnetic spin-flip amplitude and hadronic non-flip amplitude, the source of A N . The difference could be explained by an additional contribution of a hadronic spin-flip amplitude to A N .

We have searched for the K{sup +} {yields} {pi}{sup +}{gamma}{gamma} decay in the kinematic region with {pi}{sup +} momentum close to the end point. No events were observed, and the 90% confidence-level upper limit on the partial branching ratio was obtained, B(K{sup +} {yields} {pi}{sup +}{gamma}{gamma}, P > 213 MeV/c) < 8.3 x 10{sup -9} under the assumption of chiral perturbation theory including next-to-leading order ''unitarity'' corrections. The same data were used to determine an upper limit on the K{sup +} {yields} {pi}{sup +}{gamma} branching ratio of 2.3 x 10{sup -9} at the 90% confidence level.

The PP2PP experiment is one of five experiments at the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory, Long Island, New York. It is designed to measure the elastic scattering of protons at s = 50–500 GeV. The detector consists of silicon strip detectors mounted in Roman Pots and installed in the RHIC ring 60 m from the interaction region. During the engineering run of 2002 and physics run of 2003 the detectors were inserted as close as 15 mm from the proton beam. An overview of the experiment and details of the detector design and performance will be presented.

The first result of the pp2pp experiment at RHIC on elastic scattering of polarized protons at sqrt{s} = 200 GeV is reported here. The exponential slope parameter b of the diffractive peak of the elastic cross section in the t range 0.010, 9 pages 5 figures

We have performed a measurement of the K + !� + � 0 decay and have observed 2×10 4 events. The best fit to the decay spectrum gives a branching ratio for direct photon emission of (4.7 ± 0.8 ± 0.3) × 10 6 in the � + kinetic energy region of 55 to 90 MeV and requires no component due to interference with inner bremsstrahlung.

We report the first measurement of a structure-dependent component in the decay ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\gamma}$. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is $|{F}_{V}{+F}_{A}|\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.165\ifmmode\pm\else\textpm\fi{}0.007\ifmmode\pm\else\textpm\fi{}0.011$. This corresponds to a branching ratio of $B({\mathrm{SD}}^{+})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}(1.33\ifmmode\pm\else\textpm\fi{}0.12\ifmmode\pm\else\textpm\fi{}0.18)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$. We also set the limit $\ensuremath{-}0.04l{F}_{V}{\ensuremath{-}F}_{A}l0.24$ at $90%$ C.L.

We have constructed an endcap photon detector with undoped cesium iodide (CsI) crystals for K/sup +//spl rarr//spl pi//sup +//spl nu//spl nu. >

A search for the decays ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ and ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{X}^{0}$, where ${X}^{0}$ is any weakly interacting neutral particle or system of neutral particles with $150l{M}_{{X}^{0}}l250$ MeV/${\mathit{c}}^{2}$, was performed in the pion kinematic region below the ${K}_{\ensuremath{\pi}2}({K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0})$ peak. An upper limit on $B({K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}})$ is set at 1.7 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}8}$ (90% C.L.) and $B({K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{X}^{0})$ is restricted to the ${10}^{\ensuremath{-}7}$ level or lower. Limits are also set for the production of ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ through scalar or tensor interactions at 1.8 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}8}$ and 1.0 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}8}$ (90% C.L.), respectively.

An upper limit on the branching ratio for the decay [ital K][sup +][r arrow][pi][sup +][nu][bar [nu]] is set at 7.5[times]10[sup [minus]9] (90% C.L.) using the kinematic region above the [ital K][sub [pi]2]([ital K][sup +][r arrow][pi][sup +][pi][sup 0]) peak. When combined with our result from below the [ital K][sub [pi]2] peak, we obtain the limit 5.2[times]10[sup [minus]9]. An upper limit of 1.7[times]10[sup [minus]9] is also found on the branching ratio for decays of the form [ital K][sup +][r arrow][pi][sup +][ital X0] where [ital X][sup 0] is any massless, weakly interacting neutral particle. Limits are also set for cases where [ital M][sub [ital X]][sup 0][gt]0.

Several series of novel banana-shaped H-bonded symmetric trimers (with two H-bonds) and asymmetric heterodimers (with one H-bond) were self-assembled by appropriate molar ratios of proton donors (H-donors) and acceptors (H-acceptors). The influences of H-bonded linking positions and aromatic ring numbers (4-8 aromatic rings in the rigid cores) as well as the chain lengths (n, m = 12 or 16, respectively, in the flexible parts) on the mesomorphism and the switching behavior of the bent-core supramolecules were evaluated and theoretically analyzed. Except for the supramolecular structures with longer rigid cores or shorter flexible chains possessing the rectangular columnar (Col(r) or B1) phase, the SmC(A)P(A) phase was revealed in most supramolecular asymmetric heterodimers and switched to the SmC(S)P(F) phase by applying electric fields. The polar smectic C phase was dominated for those with H-bonded sites apart from the core center. Interestingly, the SmA and nematic phases were observed in H-bonded asymmetric dimers with H-bonded sites close to the core center, which theoretically proved that the polar smectic C phase was disfavored due to an unfavorable bend angle (smaller than the lower limit of 110 degrees ) in the lowest-energy H-bonded conformer. Compared with the fully covalently bonded analogue, lower transition temperatures and lower threshold voltages were developed in the H-bonded asymmetric dimers with the polar smectic C phase. On the basis of the theoretical calculations of molecular modeling, the existence of polar switching behavior in the polar smectic C phase of asymmetric heterodimers was proven to be associated with their configurations with higher dipole moments and suitable bend angles. Furthermore, the lack of polar switching behavior in supramolecular symmetric trimers, which exhibited the regular SmC phase with weak electrical stabilities, was related to their configurations with smaller dipole moments and confirmed by theoretical calculations.

An upper limit on the branching ratio for the decay {ital K}{sup +}{r arrow}{pi}{sup +}{nu}{bar {nu}} is set at 3.4{times}10{sup {minus}8} (90% C.L.). In addition, a 90%-C.L. upper limit of 6.4{times}10{sup {minus}9} is set on the branching ratio for decays of the form {ital K}{sup +}{r arrow}{pi}{sup +}{ital X}{sup 0}, where {ital X}{sup 0} is any massless, weakly interacting neutral particle. Limits are also set for the case where {ital M}{sub {ital X}{sup 0}}{gt}0.

Errors in delivering a uniformly distributed radiation dose to biological and material samples exposed to charged particle beams are a significant problem for experimenters. In this paper, we discuss data collected on the uniform beam distributions produced for NASA’s Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), using a method that was conceived theoretically and tested experimentally at BNL. This method [N. Tsoupas et al., Nucl. Sci. Eng. 126, 71 (1997)NSENAO0029-5639] of generating uniform beam distributions on a plane normal to the beam’s direction relies only on magnetically focusing the transported beam; no collimation of the beam is required or any other type of interaction of the beam with materials other than the target material. The method compares favorably with alternative methods of producing such distributions, and it can be applied to the entire energy spectrum of charged particle beams that are delivered to the NSRL’s experiments by the Booster for the Alternating Gradient Synchrotron at BNL.

Uniform irradiation of biological or material samples with charged particle beams is desired by experimenters because it reduces radiation dose errors. In this paper we present results of uniform beams produced in the NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory (BNL) by a method which was developed theoretically and was proven experimentally [1,2,3] at BNL. A similar method which requires collimation of the beam, and also lacks the flexibility of the present method to produce beam various beam sizes at the target, was patented[4] in the year 1988. The present method of producing uniform beam distributions on a plane transverse to the direction of the beam, is based on purely magnetic focusing of the beam and requires no collimation of the beam or any other type of beam interaction with materials. It can also generate uniform beam distributions of various sizes. The method is favorably compared with alternative methods [5] of producing uniform beam distributions and can be applied to the whole energy spectrum of the charged particle beams that are delivered by the BNL Booster synchrotron.

Elastic scattering of polarized protons in the range of very small momentum transferred was studied for the first time at s = 200 GeV in the experiment pp2pp at RHIC. This article presents the single spin asymmetry AN and the double spin asymmetries ANN and ASS measured in this experiment.

The purpose of this new instrument is for probing beam halo and obtaining beam profiles of the resonant extracted beam at the AGS. The device described is a prototype version, to obtain data and prepare for a more permanent device. The goals of the permanent device are to allow emittances of low current, but high intensity slowly extracted beams to be accurately measured and to have a diagnostic for probing the wings of the beam distribution. The device works on secondary emission from thin targets as well as scattering into two scintillator telescopes. The targets are movable over the entire aperture at the device.

Superconducting air core toroids show great promise for use in a muon spectrometer for the SSC 1,2. Early studies by SUNY at Stony Brook funded by SSC Laboratory, have established the feasibility of building magnets of the required size3. The toroid spectrometer consists of a central toroid with two end cap toroids. The configuration under development provides for muon trajectory measurement outside the magnetic volume. System level studies on support structure, assembly, cryogenic material selection, and power are performed. Resulting selected optimal design and assembly is described.

A description of the detector and of preliminary results of work in progress in its performance is presented here for an experiment to study the decay of K + → π + ν ν .

Using a proportional-chamber spectrometer and an array of lead-glass photon detectors, we have observed 1070 K/sub L/ /sup 0/ ..-->.. ..pi../sup +/..pi../sup -/..gamma.. events. We have extracted the branching ratios of the inner-bremsstrahlumg component b (K/sub L/ /sup 0/ ..-->.. ..pi../sup +/..pi../sup -/..gamma.., k>20 MeV)/sub IB/= (1.52 +- 0.16) x 10/sup -5/, which agrees within errors with the theoretical prediction, and of the direct-emission component, b (K/sub L/ /sup 0/ ..-->.. ..pi../sup +/..pi../sup -/..gamma..)/sub DE/= (2.89 +- 0.28) x 10/sup -5/. The ..gamma..-energy spectrum for direct emission shows possible evidence for a deviation from the pure M1 shape.

Using a double arm electromagnetic calorimeter we have searched for narrow states produced in the exclusive reaction π − p→γγn at 13 GeV/c. No enhancements were observed in the mass range 2.0–4.0 GeV/c 2 . For example, the 90% confidence limit on η c production is σ ( π − p→ η c n)× B ( η c → γγ )

Differential cross sections d 2 σ d t d M X 2 are presented for the inclusive reaction p + p → X in the range 0.01 t c ) 2 , 1.3 m X 2 2 , and incident energies from 175 to 400 GeV. The results are compared with data in the 20 GeV energy region.