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in subjects: "Targets 651100* -- Nuclear Physics-- Experimental Techniques-- 1980-"  
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Development of an optically pumped polarized deuterium target

Description: The development of a polarized deuterium target for internal use at an electron storage ring is of great interest for fundamental studies in nuclear physics. In order to achieve the maximum allowable target thickness, 10/sup 14/ nuclei/cm/sup 2/, consistent with various constraints imposed by the storage ring environment, a flux of 4 x 10/sup 17/ polarized atom/s must be provided. This flux exceeds the capability of conventional atomic beam sources by an order of magnitude. We have been develop… more
Date: January 1, 1987
Creator: Young, L.; Holt, R.J.; Green, M.C. & Kowalczyk, R.
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Partner: UNT Libraries Government Documents Department
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Development of a polarized deuterium target to measure T/sub 20/ in electron storage rings

Description: The development of a polarized deuterium target to measure the analyzing power in electron scattering from the deuteron at the highest possible momentum transfer is described. Two areas of research have been simultaneously pursued: the development of a storage cell for polarized atoms (ANL and INP) and the development of a high-flux laser-driven source of polarized deuterium (ANL). The successful combination of these two technological developments will produce a polarized target having a figure… more
Date: January 1, 1989
Creator: Young, L.; Coulter, K.; Gilman, R. A.; Holt, R. J.; Kinney, E. R.; Kowalczyk, R. S. et al.
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Partner: UNT Libraries Government Documents Department
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Recent developments in laser-driven polarized sources

Description: Recent progress in the performance of laser-driven sources of polarized hydrogen and deuterium is described. The current status of the prototype source, I = 2.5 {times} 10{sup 17}s{sup {minus}1}, polarization = 0.29 (including atomic fraction), is comparable to classical Stern-Gerlach sources. A scheme to improve source performance by approximately an order of magnitude, using a combination of optical-pumping spin-exchange and RF transitions, is outlined. 8 refs., 2 figs., 1 tab.
Date: January 1, 1990
Creator: Young, L.; Coulter, K. P.; Holt, R. J.; Kinney, E. R.; Kowalczyk, R. S.; Potterveld, D. H. et al.
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Partner: UNT Libraries Government Documents Department
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Absolute polarization standards at medium and high energies. [200 to 900 MeV]

Description: Although measurement of a polarization asymmetry is rather easy, the normalization of the measurement to obtain the analyzing power requires an absolute knowledge of the beam polarization or comparison with a known standard analyzing power. Such calibration standards can be hard to find. This paper concentrates on medium and higher energies, and divides the techniques into four categories: double scattering, polarized target methods, polarized source methods, and theoretical methods. Secondary … more
Date: January 1, 1980
Creator: McNaughton, M.W.
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Partner: UNT Libraries Government Documents Department
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Polarized nuclear targets

Description: The static and dynamic methods for producing polarized targets are briefly discussed and compared. Nuclei that have been polarized by these methods are summarized. The equipment necessary for producing a working target is described, as are the capabilities presently available at LAMPF. A short description is presented of a polarized /sup 13/C target proposed for use at the LAMPF HRS spectrometer, as an example of a polarized target for use in nuclear physics research.
Date: January 1, 1986
Creator: Jarmer, J. J.
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High resolution inelastic gamma-ray measurements with a white neutron source from 1 to 200 MeV

Description: Measurements of prompt gamma rays following neutron-induced reactions have recently been made at the spallation neutron source at the WNR target area of LAMPF using germanium detectors. These experiments provide extensive excitation function data for inelastic neutron scattering as well as for other reactions such as (n,{alpha}), (n,n{alpha}), (n,p), (n,np), (n,nnp) and (n,xn) for 1 {le} {times} {le} 11. The continuous energy coverage available from 1 MeV to over 200 MeV is ideal for excitation… more
Date: January 1, 1990
Creator: Nelson, R. O.; Laymon, C. M. & Wender, S. A.
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Pion and kaon interferometry of nuclear collisions

Description: In the study complex reactions, the simple space-time interpretation of pion interferometry often breaks down due to strong correlations between spatial and momentum coordinates. In those cases, pion interferometry is still useful as a complementary test of specific dynamic models, but a refined formalism must be used, as discussed in the introduction. With this formalism, we show that recent NA35 data on O + Au {yields} {pi}{sup {minus}}{pi}{sup {minus}} + X at 200 AGeV are consistent with bot… more
Date: August 4, 1989
Creator: Gyulassy, M. & Padula, S. S.
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Nuclear physics with internal targets in electron storage rings

Description: Two key experiments in nuclear physics will be discussed in order to illustrate the advantages of the internal target method and demonstrate the power of polarization techniques in electron scattering studies. The progress of internal target experiments will be discussed and the technology of internal polarized target development will be reviewed. 43 refs., 11 figs.
Date: October 24, 1986
Creator: Holt, R.J.
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Partner: UNT Libraries Government Documents Department
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LAMPF polarized sup 13 C targets

Description: Ethylene glycol, 1-butanol, and toluene highly enriched in {sup 13}C have been used at LAMPF to produce dynamically polarized {sup 13}C targets for scattering experiments with protons and pions. Preparation of the materials and characteristic properties of these targets are described. 17 refs., 1 fig.
Date: January 1, 1990
Creator: Penttilae, S.; Jarmer, J. J.; Tanaka, N. (Los Alamos National Lab., NM (USA)); Bartlett, M. L.; Johnson, K.; Hoffmann, G. W. et al.
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Opportunities for research program development at LANSCE

Description: The availability of intense neutron beams from facilities associated with the Proton Storage Ring and LANSCE has stimulated the development of neutron research well beyond the mainstream of neutron scattering. A description of this extended program is given along with prospects for further growth. 23 refs., 11 figs., 4 tabs.
Date: January 1, 1988
Creator: Bowman, C. D.
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Partner: UNT Libraries Government Documents Department
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Analyzing-power formalism for three-body final states

Description: Various relations important for extraction of analyzing powers from data on reactions involving three particles in the final state were derived. Several of the results pertinent for spin-1/2 and spin-1 polarized beams are presented here. These may be used in analysis of the /sup 1/H(d-vector,pp)n reaction. 3 figures. (RWR)
Date: January 1, 1980
Creator: Ohlsen, G.G.; Brown, R.E.; Correll, F.D. & Hardekopf, R.A.
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Studies of nuclear structure in antinucleon charge-exchange reactions

Description: The antinucleon-nucleus charge exchange reaction is discussed an its use as a probe of isovector excitations in nuclei is described. Attention is drawn to the fact that the (anti p,anti n) reaction will predominantly excite ''pionic'' (i.e., longitudinal spin) modes in nuclei. Comparison between (anti p,anti n) and (n,p) reactions is made. Plans for (anti p,anti n) experiments in the near future are mentioned. 21 refs., 3 figs.
Date: January 1, 1986
Creator: Auerbach, N.
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Partner: UNT Libraries Government Documents Department
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Results obtained using the Plastic Ball

Description: Single-particle inclusive experiments, and experiments that additionally measure a few correlations like the associated multiplicity, have provided the main contribution to our present understanding of high-energy heavy-ion collisions. The results from those experiments are in overall agreement with calculations of the cascade and hydrodynamical models. In the cascade model the collision of two nuclei is simulated as a cascade of nucleon-nucleon collisions using measured N-N cross sections. The… more
Date: August 1, 1983
Creator: Ritter, H. G.; Gustafsson, H. A. & Gutbrod, H. H.
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Varied applications of a new maximum-likelihood code with complete covariance capability. [FERRET, for data adjustment]

Description: Applications of a new data-adjustment code are given. The method is based on a maximum-likelihood extension of generalized least-squares methods that allow complete covariance descriptions for the input data and the final adjusted data evaluations. The maximum-likelihood approach is used with a generalized log-normal distribution that provides a way to treat problems with large uncertainties and that circumvents the problem of negative values that can occur for physically positive quantities. T… more
Date: January 1, 1978
Creator: Schmittroth, F.
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Partner: UNT Libraries Government Documents Department
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Intermediate energy spin physics. Appendix 6

Description: Topics include nuclear information from proton spin observables in elastic scattering, nuclear information from proton spin observables in inelastic scattering, recent measurements at the HRS utilizing a focal plane polarimeter, proton spin observables in natural parity transitions, and proton spin transfer observables in unnatural parity transitions. 47 references.
Date: January 1, 1983
Creator: Igo, G.
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Partner: UNT Libraries Government Documents Department
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Fast neutron capture with a white neutron source

Description: A system has been developed at the Los Alamos National Laboratory to measure gamma-rays following fast neutron reactions. The neutron beam is produced by bombarding a thick tantalum target with the 800 MeV proton beam from the LAMPF accelerator. Incident neutron energies, from 1 to over 200 MeV, are determined by their times of flight over a 7.6-m flight path. The gamma-rays are detected in five 7.6 x 7.6-cm cylindrical bismuth germanate (BGO) detectors which span an angular range from 45/sup 0… more
Date: January 1, 1984
Creator: Wender, S. A. & Auchampaugh, G. F.
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Partner: UNT Libraries Government Documents Department
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Nuclear Structure and Reactions Studied With the Darmstadt-Heidelberg Crystal Ball

Description: Angular momentum distribution in compound nuclei have been derived from ..gamma..-ray multiplicities and angular distributions measured with the Darmstadt-Heidelberg crystall ball. The influence of dynamic barrier fluctuation on the amount of angular momentum absorbed in the fusion process is discussed. Entrance channel effects have been observed which result in different decay paths for compound nuclei at the same excitation energy and spin in different target-projectile combinations. The ..ga… more
Date: January 1, 1984
Creator: Metag, V.; Fischer, R. D.; Koch, G.; Kuehn, W.; Muehlhans, R.; Novotny, R. et al.
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Partner: UNT Libraries Government Documents Department
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Spin observables at intermediate energies: a tool in viewing the nucleus

Description: This paper attempts to summarize some of the advances made in intermediate nuclear physics through measurements of spin observables, notably in the range of bombarding energies from 100 to 1000 MeV. Relative to measurements of cross section, spin observables offer a highly selective filter in viewing the nucleus. Their general utility is found in their sensitivity to particular nuclear transitions and is further augmented by their simple connections to the NN force. The advantage of higher ener… more
Date: January 1, 1986
Creator: McClelland, J. B.
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Partner: UNT Libraries Government Documents Department
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