Physical Sciences and Mathematics Commons^™

Collective Expansion In Central Au+Au Collisions, W. C. Hsi, G. J. Kunde, J. Pochodzalla, W. G. Lynch, M. B. Tsang, M. L. Begemann-Blaich, D. R. Bowman, R. J. Charity, F. Cosmo, A. Ferrero, C. K. Gelbke, T. Glasmacher, T. Hofmann, G. Imme, I. Iori, J. Hubele, J. Kempter, P. Kreutz, W. D. Kunze, V. Lindenstruth, M. A. Lisa, U. Lynen, M. Mang, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilvie, Graham F. Peaslee, G. Raciti, F. Rosenberger, H. Sann, R. Scardaoni, A. Schüttauf, C. Schwarz, W. Seidei, V. Serfling, L. G. Sobotka

Faculty Publications

Energy spectra for intermediate mass fragments produced in central Au + Au collisions at EA=100 MeV indicate a collective expansion at breakup. For the first time, values for this collective expansion energy per nucleon are extracted independently for each charge. Typically, these values are one-third to one-half of the incident kinetic energy per nucleon in the c.m. system, but they decrease with Zf, suggesting that all fragments do not participate equally in the collective expansion.

Fragmentation Of Necklike Structures, C. P. Montoya, W. G. Lynch, D. R. Bowman, Graham F. Peaslee, N. Carlin, R. T. De Souza, C. K. Gelbke, W. G. Gong, Y. D. Kim, M. A. Lisa, L. Phair, M. B. Tsang, J. B. Webster, C. Williams, N. Colonna, K. Hanold, M. A. Mcmahan, G. J. Wozniak, L. G. Moretto

Faculty Publications

Intermediate mass fragment (IMF: 3≤Z≤20 emission from necklike structures joining projectilelike and targetlike residues has been observed for peripheral Xe129 + Cunat collisions at EA=50 MeV. These fragments are emitted primarily at velocities between those of the projectilelike and targetlike residues. Relative to the charge distribution of fragments evaporated from projectilelike residues, the distribution for "neck" emission shows an enhanced emission for fragments with 4≤ZIMF≤12. This feature is consistent with expectations for the fragmentation of a noncompact cylindrical configuration.

Time Scale For Multifragmentation In Intermediate Energy Heavy-Ion Reactions, D. Fox, R. T. De Souza, T. Glasmacher, L. Phair, D. R. Bowman, N. Carlin, C. K. Gelbke, W. G. Gong, Y. D. Kim, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, M. B. Tsang, F. Zhu

Faculty Publications

Fragment-fragment correlations are used to probe the spatial-temporal extent of the emitting source in central Ar36+197Au reactions at E/A=35, 50, 80, and 110 MeV. The experimental two particle correlations are compared both with the Koonin-Pratt two-body formalism as well as a three-body Coulomb trajectory calculation. The spatial-temporal extent of the emitting system decreases with increasing incident energy. Within the context of a three-body Coulomb trajectory model the mean fragment emission time rises sharply as a function of the assumed density of the system until ρ/ρ0≊0.3. If one assumes a fixed density, the extracted mean emission time decreases with increasing assumed …

Two-Fragment Correlation Functions With Directional Cuts For Central 36ar + 197au Collisions At E/A=50 Mev, T. Glasmacher, L. Phair, D. R. Bowman, C. K. Gelbke, W. G. Gong, Y. D. Kim, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, R. T. De Souza, M. B. Tsang, F. Zhu

Faculty Publications

Two-fragment correlation functions observed in central collisions of Ar36+197Au at E/A=50 MeV are compared to many-body trajectory calculations. For the present reaction, ambiguities between source size and lifetime can be reduced by employing directional emission cuts and describing observed differences between longitudinal and transverse correlation functions. For fragments emitted above the Coulomb barrier, E/A≥6 MeV, many-body Coulomb-trajectory calculations with a surface emission model indicate emission from an extended source of short lifetime.

Two-Proton Correlation Functions For 36ar + 45sc At E/A=80 Mev, D. O. Handzy, M. A. Lisa, C. K. Gelbke, W. Bauer, F. C. Decowski, W. G. Gong, E. Gualtieri, S. Hannuschke, R. Lacey, T. Li, W. G. Lynch, C. M. Mader, Graham F. Peaslee, T. Reposeur, S. Pratt, A. M. Vander Molen, G. D. Westfall, J. Yee, S. J. Yennello

Faculty Publications

Impact-parameter filtered longitudinal and transverse two-proton correlation functions measured for 36Ar+ 45Sc collisions at E/A=80 MeV are compared to predictions of the BUU transport model. For a cut on large transverse energies, the overall trends of the measured correlated functions are rather well reproduced by calculations for central collisions. Systematic discrepancies become visible, however, for calculations with larger impact parameters.

Inter-Relations Of Solvable Potentials, Asim Gangopadhyaya, Prasanta K. Panigrahi, Uday P. Sukhatne

Physics: Faculty Publications and Other Works

Solvable Natanzon potentials in nonrelativistic quantum mechanics are known to group into two disjoint classes depending on whether the Schrödinger equation can be reduced to a hypergeometric or a confluent hypergeometric equation. All the potentials within each class are connected via point canonical transformations. We establish a connection between the two classes with appropriate limiting procedures and redefinition of parameters, thereby inter-relating all known solvable potentials.

Energy Dependence Of Multifragmentation In 84kr+197au Reactions, Graham F. Peaslee, M. B. Tsang, C. Schwarz, M. J. Huang, W. S. Huang, W. C. Hsi, C. Williams, W. Bauer, D. R. Bowman, M. Chartier, J. Dinius, C. K. Gelbke, T. Glasmacher, D. O. Handzy, M. A. Lisa, W. G. Lynch, C. M. Mader, L. Phair, M-C. Lemaire, S. R. Souza, G. Van Buren, R. J. Charity, L. G. Sobotka, G. J. Kunde, U. Lynen, J. Pochodzalla, H. Sann, W. Trautmann, D. Fox, R. T. De Souza, G. Peilert, W. A. Friedman, N. Carlin

Faculty Publications

The relationship between observed intermediate mass fragment and total charged particle multiplicities has been measured for Kr84 + Au197 collisions at energies between E/A=35 and 400 MeV. Fragment multiplicities are greatest for central or near-central collisions. For these collisions, fragment production increases up to E/A≊100 MeV, and then decreases at higher energies.

Time Scale For Proton Emission From Highly Excited Projectiles, R. J. Charity, L. G. Sobotka, G. Van Buren, F. A. Tibbals, J. Barreto, D. R. Bowman, M. Chartier, J. Dinius, D. Fox, C. K. Gelbke, D. O. Handzy, W. C. Hsi, P. F. Hua, A. S. Kirov, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, L. Phair, D. G. Sarantites, C. Schwarz, R. T. De Souza, M. B. Tsang, C. Williams

Faculty Publications

Highly fragmented exit channels produced by the decay of excited 24Mg projectiles were detected. The longitudinal velocity spectra of protons and alpha particles from such channels are offset. This offset is consistent with post-breakup Coulomb accelerations from the 197Au target nuclei implying that the protons were emitted within 3 X 10−22 s after the target-projectile separation.

Electromagnetic Dissociation Of 238u At 120 Mev/A, M. L. Justice, Y. Blumenfeld, N. Colonna, D. N. Delis, G. Guarino, K. Hanold, J. C. Meng, Graham F. Peaslee, G. J. Wozniak, L. G. Moretto

Faculty Publications

Electromagnetic fission cross sections of a 120 MeV/nucleon U238 beam incident on five targets, Be9, Al27, Cunat, Agnat, and Unat, have been extracted from measurements of projectile velocity fission fragments. The nuclear interaction contributions to the experimentally observed cross sections were determined by extrapolation from the Be target data using a geometrical scaling model and by an empirical decomposition of the fission charge distributions. The results are compared to model calculations in which electric quadrupole excitations have been included.

Vandalism Of Rock Art For Enhanced Photography, S. D. Chaffee, M. Hyman, M. W. Rowe

Canyonlands Research Bibliography

Direct radiocarbon dating of pictographs has recently become possible. The authors report here the deleterious effects on such dating of hydrocarbon contamination of a pictograph in southeastern Utah. In order to enhance contrast between a pictograph and its rock substrate, some photographers have wetted pictographs with kerosene or similar substances; such 'enhancement' renders radiocarbon dates useless. Some treatments proposed for rock art deterioration may cause similar problems.

Tamias Rufus, Stephanie L. Burt, Troy L. Best

Canyonlands Research Bibliography

No abstract provided.

1994 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 1994.

Chesapeake Bay Atlas, Us Epa Monitoring Program Water Quality Data 1984-1991, Sarah E. Rennie, Bruce Neilson

Data

The original data is in the folder RAWDATA under the folder DOSISO. Within RAWDATA there are 3 subdirectories : TSOPH holds temperature, salinity, diss.O2 and pH. WQ9 h

olds Chl-A, PO4,TotalN, NH4, Nitrate, Si, TOC, TSS & TotalP WQ6 holds DissInorgN, NO2, Part.PHOS, Part.C, Part.N, and TDissN The original measurements are held in columnar ASCII text files suitable for importing into spreadsheets (columns separated by spaces, not tabs). The files are arranged in subdirectories by water year (October through September). The data is as it came from the US EPA Chesapeake Bay Program Office in Annapolis (CSC) in November 1992. …

1994 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 1994.