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We measured the performance of a 2"×2" tapered cylindrical SrI2:Eu, a 2" × 3" cylindrical CeBr3, a 2" × 0.3" cylindrical GYGAG:Ce. The gamma-ray energy resolution was measured up to 9 MeV. A scan along three axes of each scintillator was performed using a collimated source of 137Cs. The signals of the detectors were also digitized and compared. We tested two 1" × 1" cylindrical CLYC crystals. One was enriched with 6Li at 95% while the other was enriched with 99% of 7Li. The response of the two detectors to gamma rays, thermal and fast neutrons was measured. The PSD performances have been tested with a different types of PMTs.

Scintillation light is often detected by photo-multiplier tube (PMT) technology. PMTs are however intrinsically non linear devices, especially when operated with high light yield scintillators and high input photon flux. Many physical effects (e.g. inter-dynode field variation, photocathode resistivity, etc.) can spoil the ideal PMT behavior in terms of gain, ending up in what are addressed as the under-linearity and over-linearity effects.Established techniques implemented in the PMT base (e.g. increasing bleeding current, active voltage divider, etc.) can mitigate these effects, but given the unavoidable spread in manufacturing and materials, it turns out that, with respect to linearity at the percent level, every PMT sample is a story of its own.The residual non linearity is usually accounted for with polynomial correction of the spectrum energy scale, starting from the position of a few known energy peaks of calibration sources, but uncertainly remains in between of calibration peaks. We propose to retrieve the calibration information from the entire energy spectrum and not only the position of full energy peaks (FEP), by means of an automatic procedure that also takes into account the quality (signal/noise ratio) of the information about the non-linearity extracted from the various regions of the spectrum.

Jolie, J. Ilie, G. Reiter, P. Richard, A. Scherillo, A. Striepling, T. Warr, N. Banu, A. Becker, F. Bednarczyk, P. Doornenbal, P. Gerl, J. Grawe, H. Gorska, M. Kojouharov, I. Mandal, S. Saito, N. Saito, T. R. Wollersheim, H. -J. Mallion, S. Neyens, G. Turzo, K. Van Duppen, P. Vermeulen, N. Podolyak, Zs. Gelletly, W. Regan, P. H. Walker, P. M. Catford, W. N. Liu, Z. Williams, S. Blazhev, A. Lozeva, R. Detistov, P. Atanasova, L. Damyanova, G. Gil, D. Cortina Benlliure, J. Kurtukian Nieto, T. Caserejos, E. Daugas, J. M. Belier, G. Meot, V. Roig, O. Simpson, G. Tsekhanovich, I. S. Matea, I. Schwengner, R. Hass, M. Singh, B. S. Nara Chamoli, S. K. Goldring, G. Regev, I. Vaintraub, S. Balabanski, D. L. Lo Bianco, G. Gladnishki, K. Saltarelli, A. Petrache, C. Benzoni, G. Blasi, N. Bracco, A. Camera, F. Million, B. Leoni, S. Wieland, O. Maj, A. Kmiecik, M. Grebosz, J. Bednarczyk, P. Styczen, J. Lach, M. Meczynski, W. Mazurek, K. Pfutzner, M. Korgul, A. Ionescu-Bujor, M. Iordachescu, A. Zamfir, V. Jungclaus, A. Georgiev, G. Cullen, D. M. Freeman, S. J. Smith, A. G. Orlandi, R. Clark, R. M. Bentley, M. A. Hammond, G. Wadsworth, R. Buerger, A. Huebel, H. Rudolph, D. Fahlander, C. Simpson, J. Herzberg, R. D. Page, R. D. Nolan, P. Davidson, T. Woods, P. Bruce, A. M. Faestermann, T. Kruecken, R. Mach, H. Rubio, B. Algora, A.

The {gamma} decay of the Giant Dipole Resonance in the {sup 132}Ce compound nucleus with temperature up to {approx} 4 MeV has been measured. The symmetric {sup 64}Ni + {sup 68}Zn at E{sub beam} = 300, 400, 500 MeV and the asymmetric reaction {sup 16}O + {sup 116}Sn at E{sub beam} = 130, 250 MeV have been investigated. Light charged particles and {gamma} rays have been detected in coincidence with the recoiling compound system. In the case of the mass symmetric {sup 64}Ni induced reaction the {gamma} and charged particle spectral shapes are found to be consistent with the emission from a fully equilibrated compound nuclei and the GDR parameters are extracted from the data using a statistical model analysis. The GDR width is found to increase almost linear with temperature. This increase is rather well reproduced within a model which includes both the thermal fluctuation of the nuclear shape and the lifetime of the compound nucleus.

Recent measurements have been performed at the National Laboratoty of Legnaro using mass‐symmetric (400, 500 MeV 64Ni + 68Zn) and mass‐asymmetric (250 MeV 16O + 116Sn) entrance channel reactions to form 132Ce compound nucleus at different excitation energies (E*=150, 200 and 200 MeV, respectively). The decay of the composite system has been followed studying the γ‐rays and Light Charged Particles (LCP) spectra emitted in coincidence with the Evaporation Residues (ER). In this way the emission mechanism of the LCP, depending on the mass‐asymmetry at the entrance channel and on the projectile energy, and the results of the Full Width Half‐Maximum (FWHM) of the Giant Dipole Resonance as a function of the nuclear temperature have been studied.

The γ decay in the quasicontinuum is used to study the order-to-chaos transition in the thermally excited 163 Er nucleus. The experimental analysis is performed on high-statistics EUROBALL data, focusing on the spin region I ≈ (20–40) ¯ h, and internal excitation energy up of ≈2.5 MeV. The results are compared to cranked shell model calculations for this nucleus, taking into account the dependence on the K quantum number. Two main topics are investigated. First, the validity of the selection rules associated with the K quantum number are studied as a function of the internal energy U above yrast. K-selection rules are found to be obeyed in the decay along discrete unresolved rotational bands up to U ≈ 1.2 MeV, whereas in the interval U ≈ 1.2–2.5 MeV, where the order-to-chaos transition is expected to take place, selection rules are found to be only partially valid. Second, the line-shape analysis of γ -γ coincidence spectra provides a direct experimental measurement of the rotational and compound damping widths (� rot and � µ), yielding values of 200 and 20 keV, respectively, in good agreement with theory.

A gate-free fast-stretcher circuit has been developed for an easy acquisition of the fast and slow components of the signals produced by BaF2 scintillators, in order to discriminate the types of incident particles. In experiments where many detectors are used, these measurements are normally performed providing the signal to two QDC's (charge to digital converter) and using logical signals of different widths as gates. One gating signal is short to integrate the fast part of the signal only; the other is much longer to integrate the whole signal. Such a measurement technique has many inconveniences. One of the most critical is that the analog signals fed into the QDC must be delayed through long and cumbersome transmission lines to synchronize them with the QDC gate signals, which degrades the quality of the fast component. We have developed a new circuit structure that addresses these issues. The circuit uses no delay line. It simply builds two slow Gaussian signals: the first, called "fast", is obtained after stretching the fast signal component, and is proportional to its amplitude; the second, called "slow", is proportional to the energy of the entire signal. These outputs are easily acquired with a standard peak ADC with no gate-timing problem. An excellent fast-slow separation has been obtained even with small input signals of only a few millivolts.

The results are presented from the experiments using the EUROBALL and RFD/HECTOR arrays, concerning various aspects of collectivity in light nuclei. A superdeformed band in 42 Ca was found. A comparison of the GDR line shape data with the predictions of the thermal shape uctuation model, based on the most recent rotating liquid drop LSD calculations, shows evidence for a Jacobi shape transition in hot, rapidly rotating 46 Ti and strong Coriolis eects in the GDR strength function. The preferential feeding of the SD band in 42 Ca by the GDR low energy component was observed

CLARA is an array of 25 Clover (EUROBALL type) Ge detectors, placed at the target position of the large acceptance magnetic spectrometer PRISMA. Due to the granularity of the CLARA Ge array (100 crystals), the photopeak efficiency ($\approx$3%) and the PRISMA large acceptance ($\approx$80 msr, and 20% $\Delta$p/p), the setup is an excellent tool to investigate the structure of neutron-rich nuclei, populated in multinucleon transfer reactions and deep inelastic collisions with stable beams. Since March 2004 the setup is fully operational, and since then several experiments have been performed, with beams delivered by the LNL XTU-Tandem and the ALPI linac. In this contribution the preliminary outcome of the first experiments is shown.

The γ‐decay from excited nuclei is used to study the interplay between rotational motion and compound nucleus formation in deformed nuclei. A new analysis technique is presented which allows for the first time to directly measure the rotational and compound damping widths Γrot and Γμ from γ‐coincidence spectra. The method is first tested on simulated spectra and then applied to high‐statistics EUROBALL data on the nucleus 163Er. Experimental values of ≈200 and 20 keV are obtained for Γrot and Γμ, respectively, in the spin region I ≈ 30–40 ℏ, in good agreement with microscopic cranked shell model calculations for the specific nucleus. A dependence of rotational damping on the K‐quantum number of the nuclear states is also observed, both in experiment and theory, resulting in a ≈30% reduction of Γrot for high‐K states. This points to a delayed onset of rotational damping in high‐K configurations.

he selection rules on the K-quantum number in rapidly rotating warm nuclei are investigated analyzing quasi-continuum spectra feeding into low-K and high-K bands in 163Er. The data are compared to simulated spectra obtained using the band mixing model predictions including the residual interaction and a term representing the effect of the K-quantum number on the rotational energy. K-selection rules are found to be obeyed by the decay along excited unresolved rotational bands of heat energy up to around 1.2 MeV and angular momentum 30Planck's over 2piless-than-or-equals, slantIless-than-or-equals, slant40Planck's over 2pi. In contrast, the results corresponding to higher heat energy of 1.2 to 2.5 MeV indicate that the selection rules are only partially satisfied.

The gamma decay in the quasicontinuum from selected configurations of the rotational nucleus 163Er has been measured with the EUROBALL array. A new analysis technique has allowed for the first time to directly measure the compound and rotational damping widths Gamma (micro) and Gamma (rot). Values of Gamma (micro) approximately 20 keV and Gamma (rot) approximately 200 keV are obtained in the spin region I approximately 30-40 variant Planck's over 2pi, in good agreement with microscopic cranked shell model calculations. A dependence of Gamma (micro) and Gamma (rot) on the K-quantum number of the nuclear states is also presented.

The gamma-rays following the reaction 105 MeV 18O + 28Si have been measured using the EUROBALL IV, HECTOR and EUCLIDES arrays in order to investigate the predicted Jacobi shape transition. The high-energy gamma-ray spectrum from the GDR decay indicates a presence of large deformations in hot 46Ti nucleus, in agreement with new theoretical calculations based on the Rotating Liquid Drop model., NS2002 Conference. Legnaro, Sptember 2002; to be published in EPJA

The gamma-rays from the decay of the GDR in 46Ti compound nucleus formed in the 18O+28Si reaction at bombarding energy 105 MeV have been measured in an experiment using a setup consisting of the combined EUROBALL IV, HECTOR and EUCLIDES arrays. A comparison of the extracted GDR lineshape data with the predictions of the thermal shape fluctuation model shows evidence for the Jacobi shape transition in hot 46Ti. In addition to the previously found broad structure in the GDR lineshape region at 18-27 MeV caused by large deformations, the presence of a low energy component (around 10 MeV), due to the Coriolis splitting in prolate well deformed shape, has been identified for the first time., 8 pages, 4 figures, proceedings of the COMEX1 conference, June 2003, Paris; to be published in Nucl. Phys. A

We focus on the problem of the spatial localization of energy releasing events (hits) in segmented large-volume HPGe detectors. We present an algorithm for a precise radial coordinate estimation of events occurring at the same time in the same segment. The algorithm was designed bearing in mind that, with up to thousands of parallel channels, it is mandatory to perform the measurements in each channel with the least possible number of input data, while losing no important information and, possibly, operating on line in real time. For the sake of simulation, hits with energy ranging from 60 keV up to 2 MeV are taken into account and electronic noise and signal finite bandwidth effects are considered.

The problems of the reconstruction of the trajectory of /spl gamma/-rays and of the identification of their interaction points in segmented HpGe detectors are discussed in view of their importance in the design of the next generation of detector arrays for /spl gamma/-ray spectroscopy studies. In fact, the level of tracking of the /spl gamma/-ray interactions in the medium controls the overall detection efficiency. Tracking algorithms taking into accounts the detection segmentation together with the pulse shape analysis have been developed making use of the GEANT simulation package. The present work focuses on two main points. One is how to disentangle the pulse shape analysis effects and investigate their possibilities, the other is the study of the consequences that different types of segmentation have on the overall efficiency. Two geometries have been chosen, that of a single cylindrical detector and a spherical shell.

High‐energy γ rays emitted in the symmetric reaction 90Zr + 89Y have been measured at the Argonne National Laboratory using the LEPPEX array coupled to the Fragment Mass Analyzer (FMA). The high‐energy γ‐ray spectra emitted by the giant dipole resonance built on excited states and associated with the evaporation of 0, 1 and 2 nucleons have been measured. The statistical model analysis indicates that the radiative‐fusion process, namely the 0 particle emission channel, can be well described as a compound nucleus decay channel. In addition, the analysis of the high‐energy γ‐ray spectra associated with the different evaporation channels provides the first evidence that shell effects still play a role in determining the nuclear shapes of 179Au in the temperature interval 0.5–1 MeV.

The main aim of this study was a deeper understanding of the nuclear structure properties of the soft dipole modes in 140 Ce, excited via inelastic scattering of weakly bound 17 O projectiles. An important aim was to investigate the ‘splitting’ of the PDR into two parts: a low-energy isoscalar component dominated by neutron-skin oscillations and a higher-energy component lying on the tail of the giant dipole resonance of a rather isovector character. This was already observed for this nucleus, investigated in (α, α′) and (γ, γ′) experiments. The experiment was performed at Laboratori Nazionali di Legnaro, Italy. Inelastic scattering of 17 O ion beam at − 2 0M eV A 1 was

The 48Ti on 40Ca reactions have been studied at 300 and 600 MeV focusing on the fusion-evaporation (FE) and fusion-fission (FF) exit channels. Energy spectra and multiplicities of the emitted light charged particles have been compared to Monte Carlo simulations based on the statistical model. Indeed, in this mass region (A about 100) models predict that shape transitions can occur at high spin values and relatively scarce data exist in the literature about coincidence measurements between evaporation residues and light charged particles. Signals of shape transitions can be found in the variations of the lineshape of high energy gamma rays emitted from the de-excitation of GDR states gated on different region of angular momenta. For this purpose it is important to keep under control the FE and FF processes, to regulate the statistical model parameters and to control the onset of possible preequilibrium emissions from 300 to 600 MeV bombarding energy., Comment: 4 pages, 3 figures, Contribution to conference proceedings of the 25th International Nuclear Physics Conference (INPC 2013) Journal-ref: 25th International Nuclear Physics Conference (INPC 2013), Firenze : Italy (2013)

A new superdeformed rotational band has been observed in Er-154 using the Euroball Ge detector array. The new band and the one previously observed can be understood as based on coexisting superdeformed structures at prolate and triaxial shapes, respectively. The observation resolves long-standing difficulties in the theoretical interpretation of superdeformed states in Er-154.

The next generation of 4 pi arrays for high-precision gamma -ray spectroscopy will involve "gamma -ray tracking front-end on digital signal processing techniques, which allows to extract energy, timing and spatial information on the interactions of a gamma -ray in the Ge detector by pulse shape analysis of its signals. Utilizing the information on the positions of the interaction points and the energies released at each point the tracks of the gamma -rays in a Ge shell can be reconstructed in three dimensions.

The energy resolution of a high purity Ge detector with an efficiency of 70% was measured after it was exposed to increasing integrated fluxes of fast neutrons. The latter were produced by the reaction p+natCu → Zn+n at an incident laboratory energy of 6 MeV. The energy resolution was found to be increased by ∼ 30% after irradiation by an integrated flux of 3 × 109 neutrons/cm2.

The γ-decay of the continuum has been measured in two mass regions. The excitation function of the continuum decay as well as spectral shape and fractional Doppler shifts are discussed for both 114Te and 164Yb compound nuclei, and show the typical features of rotational collective motion. Moreover, in both cases an upper limit of Γrot is given and the number of decay-paths is determined from the fluctuation analysis method. Simulations based on microscopic calculations of the rotational damping model reproduce quite well the experimental findings for both Npath and the scaling of Γrot as a function of the mass number.

The Coulomb excitation experiment to study electromagnetic structure of low-lying states in Ca-42 with a focus on a possible superdeformation in this nucleus was performed at the Laboratori Naziona ...

The \ensuremath{\gamma} cascades feeding into low-K and high-K bands in ${}^{163}$Er are investigated analyzing variances and covariance of the spectrum fluctuations. From a large data set of 1${0}^{9}$ triple coincidences, \ensuremath{\gamma}-\ensuremath{\gamma} coincidence spectra gated by resolved low-lying rotational bands are analyzed. Low-K bands are found to be fed by a much larger effective number of cascades than high-K bands. The covariance between pairs of gated spectra shows that the cascades feeding low-K bands are different from those feeding the high-K bands. The persistence of the K-selection rules for the excited rotational bands within the angular momentum region $30\ensuremath{\Elzxh}\ensuremath{\le}I\ensuremath{\le}40\ensuremath{\Elzxh}$ is suggested as explanation.

The strength function and the angular distribution of the high energy {gamma} rays emitted by the giant dipole resonance (GDR) in hot rotating{sup 109,110}Sn nuclei have been measured at temperature {ital T}=1.8 MeV and at four values of the angular momentum {ital I}. The GDR width is {approx}2 times larger than at {ital T}=0 and increases by {approx}20% as {ital I} goes from 40 to 54{h_bar}. The {ital a}{sub 2}({ital E}{sub {gamma}}) increases by a factor of {approx}2. Based on these two facts and on the comparison with theory we conclude that large deformations driven by {ital I} and combined with shape and orientation fluctuations are responsible for the measured increases. Collisional damping is constant and practically equal to the {ital T}=0 case.

Neutron-rich nuclei beyond N = 126 in the lead region were populated by fragmenting a 238U beam at 1 GeV A on a Be target and then separated by the Fragment Separator (FRS) at GSI. Their isomeric decays were observed, enabling study of the shell structure of neutron-rich nuclei around the Z=82 shell closure. Some preliminary results are reported in this paper.

We report here on the measurements of one-particle transfer cross sections and quasi-elastic scattering of 32S+64Ni at energies around and well-below the Coulomb barrier. The experiment has been perormed with the Legnaro Recoil Mass Spectrometer. We have measured the excitation function at θcm = 170° from Elab = 68.3 to 92.4 MeV and the angular distribution at Elab = 81.3 MeV from θcm = 120° to 170°. The results have been analysed in the framework of the complex WKB theory and the semiclassical approach based on Coulomb trajectories.

Dendranthema×grandiflorum (Ramat.) were grown in either a peat-based or pine bark—based medium and drenched with growth retardants at a range of concentrations to generate dose : response curves. The effect of ancymidol, paclobutrazol, and uniconazole on stem elongation was less in the pine bark—based than in the peat-based medium. Generally, the concentrations required to achieve the same response were 3- to 4-fold as high in the pine bark—based medium as in the peat-based medium. However, chlormequat was slightly more active in the pine bark—based medium than in the peat-based medium. Chemical names used: α-cyclopropyl-α—(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); (±)-(R*,R*)-β-[(4-chlorophenyl)methyl]-α-(1,1-di methyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol); (E)-(RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pent -l-en-3-ol (uniconazole); 2-chloroethyltrimethylammonium chloride (chlormequat).

The influence of production practices on runoff from container nurseries was investigated in Spring 2003 (March to July) and Fall 2003 (August to January). Viburnum odoratissimum (Ker-Gawl.) liners were planted in 3.8-L containers with a 2 pine bark: 1 sand: 1 Canadian peat substrate and placed on 1.5 m2-platforms at one of two plant spacing densities: 16 or 32 plants/m2 [spaced to 16 plants/m2 after 13 weeks (spring) or 14 weeks (fall)]. Overhead sprinkler irrigation was applied daily (1 cm) and runoff collected weekly. Osmocote 18 N-2.6 P-10 K was surface-applied to each container (15 g) in the spring and surface-applied or incorporated in the fall. Cumulative runoff averaged 1240 L·m-1; in spring (19 weeks) and 1050 L·m-1; in fall (20 weeks), which represented 72% and 66% of applied irrigation plus rainfall, respectively. The lower density spacing resulted in a 19% increase in cumulative runoff in spring (1340 vs. 1130 L·m-1) but had no effect in fall (970 vs. 890 L·m-1). Weighted average ECwa of runoff decreased 10% (0.436 vs. 0.485 dS·m-1) and 12% (0.420 vs. 0.476 dS·m-1) with the lower density spacing in spring and fall, respectively. ECwa in fall was not affected by fertilizer method. Plant size index [(height + width)/2] was reduced 22% in both spring (38.7 vs. 49.7 cm) and fall (26.9 vs. 34.4 cm) when plants were grown at the lower density spacing throughout production. This reduction in plant size was attributed to container heat stress. Plant size was unaffected by fertilizer application method (fall) but fertilizer incorporation resulted in greener plants than surface-applied fertilizer (60 vs. 53 SPAD readings).

An experiment aiming at finding evidence for γ-decay of the giant dipole resonance built on superdeformed nuclear states has been made using the EUROBALL γ-detector array coupled to the large BaF2 detectors of the HECTOR system. The reaction 110Pd(37Cl, 4n)143Eu at beam energies of 165 MeV and 170 MeV has been employed. A report of the analysis of a part of the data at Ebeam = 165 MeV is given here. Results based on more inclusive and on very exclusive high-energy γ-ray spectra are presented. In particular, the spectrum of high-energy γ-rays gated by low-energy transitions between states fed by the superdeformed states are found to show some excess of yield in the 9–11 MeV region with respect to the spectrum gated by transitions not fed by the superdeformed states. This is the γ-ray energy region where one expects to find the γ-decay of the giant dipole oscillation along the long axis of a superdeformed axially symmetric nucleus. The measured excess is found to be of the same order as that predicted by schematic statistical model calculations assuming that the excitation of the GDR built on excited states is restricted to a region of the phase space a few MeV above the yrast line at very high spins.

A broccoli seedling bioassay was used to compare the activity of paclobutrazol applied at six concentrations to 20 media component samples mixed 1:1 (v:v) with vermiculite. Results indicated that 4-, 5-, and 10-fold higher media paclobutrazol concentrations were required in old composted pine bark, fresh pine bark, and composted pine bark samples, respectively, to achieve the same activity observed in sphagnum peatmoss. Paclobutrazol bioassay activity in coir was similar to the activity observed in peat, while activity in vermiculite and perlite was greater than in peat. In a second trial, paclobutrazol activity was reduced more in the fine (4 mm) fractions. In a third trial, petunias grown in a 60% composted pine bark:0% peat mix required a »14-times higher drench paclobutrazol concentration to achieve the same size control as petunia grown in a 0% composted bark:60% peat mix. It was concluded that media components differed greatly in their influence on paclobutrazol activity and that the bioassay procedure might serve as a useful tool for predicting media–paclobutrazol interactions.

Trials involving growth retardants applied in subirrigation water were conducted to evaluate the potential for this method of application and to determine critical concentrations for production of several floriculture crops. Eight concentrations of paclobutrazol or ancymidol ranging from 0 to 0.1 mg·liter–1 were applied continuously (from planting) to five crops. Based upon regression equations, paclobutrazol concentrations resulting in 20% size reduction were 0.005, 0.024, 0.017, >0.1, and >0.1 mg·liter–1 for begonia, chrysanthemum, impatiens, petunia, and salvia, respectively; for ancymidol, respective concentrations were 0.003, 0.01, 0.10, >0.1, and 0.058 mg·liter–1. A second set of trials compared the efficacy of a one-time vs. continuous application of paclobutrazol via subirrigation starting at 2 to 3 weeks after planting. For begonia, a one-time subirrigation application of 0.01 mg·liter–1 paclobutrazol resulted in 30% size reduction, while 0.003 mg·liter–1 applied continuously resulted in 20% size reduction. For impatiens, a one-time subirrigation application of 0.1 mg·liter–1 paclobutrazol resulted in 31% size reduction while 0.03 mg·liter–1 applied continuously resulted in 40% size reduction.

Drench applications of paclobutrazol (PBZ) are becoming increasingly popular as a means for controlling height in potted plants, and research is being conducted to quantify the distribution of PBZ following applications. In one trial, 120 ml of 0 or 1 mg 1-1 PBZ were applied to 15-cm pots filled with either Vergro Klay Mix (no bark) or Metro Mix 500 (bark). A bioassay using broccoli (Brassica oleracea L. Italica) seedlings was used to quantify PBZ in leachates and media following treatment drenches. Leachate PBZ concentrations were lower for Vergro than for Metro Mix 500; however, leachates for both media were –1. Concentrations of PBZ in media decreased with depth and were four to 10 times higher in the uppermost 2.5 cm than in lower horizons. For the uppermost 2.5 cm of media, higher PBZ concentrations were recovered in Metro Mix 500 than in Vergro. A follow-up study will compare surface vs. subsurface application methods on the movement of PBZ into pots.

The volume self-diffusion coefficients of 51Cr and 59Fe in 16 FeNiCr alloys with an f.c.c. lattice were measured using the modified Gruzin method in the temperature ranges 1298–1548 K for iron and 1286–1536 K for chromium. The self-diffusion coefficients, pre-exponential factors and activation energies for iron and chromium are tabulated. The concentration dependence obtained cannot be expressed by a simple mathematical relation; it is of higher order with a local minimum near the composition Fe-55 wt.%Ni-20 wt.%Cr. A critical analysis of the results obtained as well as previous knowledge made it possible to find the following relation between the self-diffusion coefficients of components which are valid over the whole temperature and concentration ranges examined: DNi∗: DFe∗: DCr∗ = 1:1.2:2 From the thermodynamic activity measurements, values of the thermodynamic diffusion factors in the ternary FeNiCr system and further values of the interdiffusion coefficients in this system were calculated. In this way a complete description of the diffusion processes in the ternary system was obtained. A comparison of the calculated interdiffusion coefficients with the experimental values found by other researchers was made.

Inclusive proton-induced charged pion production was studied on 12 C, 89 Y and nat Pb at 201 and 180 MeV. A QQD spectrometer was used for forward angles and a plastic scintillator range spectrometer for backward angles. The angular dependence, variation with the pion energy, and total cross sections are deduced from doubly differential cross section measurements.

Spin structure and cross section data for Δ production in the (n, p-like reaction (d, 2p[1S0]) on p, d and 12C targets are presented. At laboratory kinetic energies 2 GeV and 1.6 GeV, and forward scattering angles, we find dominance of spin transverse over spin longitudinal cross section for free Δ production. On the nucleus 12C we find significant enhancement of the transverse dominance, and a large downwards shift in the peak position of the laboratory energy transfer associated with the production of the Δ.

The measurements of V hetero-diffusion in f.c.c. cobalt, which reveal an evident magnetic diffusion anomaly (MDA), are reported. With respect to the fact that the equations derived in a previous work on the basis of Kirkwood's method (KM) cannot be applied when analysing MDA in trian-gular or honeycomb plane lattices, or in f.c.c. lattices, equations based on quasi-chemical approxima-tion (QCHM) are introduced. These equations are applied in 48V/Co hetero-diffusion analysis and in 59Fe/α-Fe and in 60Co/α-Fe [1]re-analysis, which yield: diffusion characteristics D0 and H in paramagnetic and in ferromagnetic matrices; exchange integrals J/k for α-Fe and Co, para-magnetic temperatures Tp, ratios ΔHM/ΔHM of the excess activation enthalpies of vacancy migra-tion (M) and formation (F), and experimental constants K1 The results obtained for α-Fe are compared with the parameters published in a previous work obtained by Hie use of KM.

Results on the Δ excitation by heavy ion charge exchange are presented. 900 MeV per nucleon 12C, 16O, 20Ne and 1100 MeV per nucleon 12C have been used. The Δ excitation strength depends on the projectile — ejectile nature and on the incident energy. The role of the target mass is also discussed. The peak for the Δ in nuclei is energy shifted from the free Δ peak.

A complex analysis of the selfdiffusion, interdiffusion and vaporization data in the Ni-V system is presented in this paper. Full descriptions of diffusion processes in this system were given. Temperature dependence of the selfdiffusion coefficients of components in the solid solution region fulfil the Arrhenius law. Concentration dependences of the selfdiffusion characteristics (D,D0,ΔH) have the extremes in the region of 25 at. % of vanadium (minimum for logD=f(x), maximum for logD0=f(x) andΔH=f(x)).

Inclusive production of charged pions induced by 3 He has been studied on 12 C, 27 Al, 89 Y and nat Pb at 283 MeV. The angular distributions and the total cross sections are deduced from the doubly differential cross section measurements.