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Full-Text Articles in Physical Sciences and Mathematics
Multifragmentation In E/A=35 Mev Collisions: Evidence For A Coulomb Driven Breakup?, M. D'Agostino, G. J. Kunde, P. M. Milazzo, J. D. Diniu, M. Bruno, N. Colonna, M. L. Fiandri, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, W. C. Hsi, M. Huang, M. A. Lisa, W. G. Lynch, P. F. Mastinu, C. P. Montoya, A. Moroni, Graham F. Peaslee, L. Phair, R. Rui, C. Schwarz, M. B. Tsang, G. Vannini, C. Williams
Multifragmentation In E/A=35 Mev Collisions: Evidence For A Coulomb Driven Breakup?, M. D'Agostino, G. J. Kunde, P. M. Milazzo, J. D. Diniu, M. Bruno, N. Colonna, M. L. Fiandri, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, W. C. Hsi, M. Huang, M. A. Lisa, W. G. Lynch, P. F. Mastinu, C. P. Montoya, A. Moroni, Graham F. Peaslee, L. Phair, R. Rui, C. Schwarz, M. B. Tsang, G. Vannini, C. Williams
Faculty Publications
Multifragment disintegrations have been measured for central Au+Au collisions at EA=35 MeV. Fragment emission occurs predominantly at low center of mass energies of about EA≈5 MeV, consistent with a Coulomb dominated breakup of a single source. Mean fragment multiplicities of ⟨NIMF⟩≈10.8 are extracted after correction for the detection efficiency. The fragment charge distributions decrease much more gradually than expected from scaling laws recently applied to the extraction of critical exponents for the nuclear liquid-gas phase transition from nuclear collisions.
Prompt And Sequential Decay Processes In The Fragmentation Of 40 Mev/A 20ne Projectiles, R. J. Charity, L. G. Sobotka, N. J. Robertson, D. G. Sarantites, J. Dinius, C. K. Gelbke, T. Glasmacher, D. O. Handzy, W. C. Hsi, M. J. Huang, W. G. Lynch, C. P. Montoya, Graham F. Peaslee, C. Schwarz, M. B. Tsang
Prompt And Sequential Decay Processes In The Fragmentation Of 40 Mev/A 20ne Projectiles, R. J. Charity, L. G. Sobotka, N. J. Robertson, D. G. Sarantites, J. Dinius, C. K. Gelbke, T. Glasmacher, D. O. Handzy, W. C. Hsi, M. J. Huang, W. G. Lynch, C. P. Montoya, Graham F. Peaslee, C. Schwarz, M. B. Tsang
Faculty Publications
The fragmentation of E/A=40 MeV Ne20 projectiles into exit channels containing only p, d, t, He3, α, He6, Li6, and Li7fragments has been investigated. Relative shifts between the average longitudinal velocity of each fragment type were measured with Sn120 and Au197 targets. A post-breakup Coulomb acceleration component of these shifts was isolated. Its magnitude indicates that the projectile broke up while in near contact with the target. On the other hand, correlations between projectile fragments indicate that a significant fraction of these fragments are produced by the sequential decay of long- and short-lived unstable intermediates. A fully sequential decay process, …
Pion Fusion In Peripheral Pp Collisions, Alec Schramm, Burndt Muller
Pion Fusion In Peripheral Pp Collisions, Alec Schramm, Burndt Muller
Alec J Schramm
We estimate the cross section for quasielastic double pion exchange in high energy proton-proton collisions. Total and elastic ππ cross sections are calculated in an equivalent pion approximation, with pion-baryon vertices taken from chiral perturbation theory.
Coincidence Correlations Between Light Charged Particles In The Matched Reactions 905 And 1030 Mev121sb + 27al And 550 And 750 Mev 86kr + 63cu, Winifred E. Parker, Morton Kaplan, David J. Moses, John M. Alexander, Roy B. Lacey, Dalva M. De Castro Rizzo, J. Bolger, A. Narayanan, Graham F. Peaslee, D. G. Popescu
Coincidence Correlations Between Light Charged Particles In The Matched Reactions 905 And 1030 Mev121sb + 27al And 550 And 750 Mev 86kr + 63cu, Winifred E. Parker, Morton Kaplan, David J. Moses, John M. Alexander, Roy B. Lacey, Dalva M. De Castro Rizzo, J. Bolger, A. Narayanan, Graham F. Peaslee, D. G. Popescu
Faculty Publications
Coincidence measurements have been made between and a second particle () produced in the reactions 905 and 1030 MeV and 550 and 750 MeV . All four of the reactions lead to composite systems of 149Tb∗ or 148Gd∗ which facilitates comparisons of matched reactions. In the two reactions and the 550 MeV reaction, the particle-particle coincidences are dominated by processes that lead to evaporation residues. In the 750 MeV reaction, about half of the 1H and 4He are associated with evaporation residue production. These particle-particle coincidences arise from cross sections that are subsets of the total evaporation residue cross sections. …
Evidence For The Reducibility Of Multifragment Emission To An Elementary Binary Emission In Xe-Induced Reactions, K. Tso, L. Phair, A. Colonna, W. Skulski, G. J. Wozniak, L. G. Moretto, D. R. Bowman, M. Chartiet, C. K. Gelbke, W. G. Gong, W. C. Hsi, Y. D. Kim, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, C. Schwarz, R. T. De Souza, M. B. Tsang, F. Zhu
Evidence For The Reducibility Of Multifragment Emission To An Elementary Binary Emission In Xe-Induced Reactions, K. Tso, L. Phair, A. Colonna, W. Skulski, G. J. Wozniak, L. G. Moretto, D. R. Bowman, M. Chartiet, C. K. Gelbke, W. G. Gong, W. C. Hsi, Y. D. Kim, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, C. Schwarz, R. T. De Souza, M. B. Tsang, F. Zhu
Faculty Publications
Multifragmentation for 129Xe-induced reactions on several targets (natCu, 89Y, 165Ho, 197Au) has been studied at . The probability of emitting n intermediate mass fragments is shown to be binomial at each transversal energy and reducible to an elementary binary probability p. For each target and at each bombarding energy, p shows a thermal behavior as demonstrated by linear Arrhenius plots. A nearly universal linear Arrhenius plot is observed at each bombarding energy, independent of target. The sensitivity of p to the Zthreshold points to its physical significance and rules out auto-correlation effects.
Understanding Proton Emission In Central Heavy-Ion Collisions, D. O. Handzy, W. Bauer, F. C. Daffin, S. J. Gaff, C. K. Gelbke, T. Glasmacher, E. Gualtieri, S. Hannuschke, M. J. Huang, G. J. Kunde, R. Lacey, T. Li, M. A. Lisa, W. J. Llope, W. G. Lynch, L. Martin, C. P. Montoya, R. Pak, Graham F. Peaslee, S. Pratt, C. Schwarz, N. Stone, M. B. Tsang, A. M. Vander Molen, G. D. Westfall, J. Yee, S. J. Yennello
Understanding Proton Emission In Central Heavy-Ion Collisions, D. O. Handzy, W. Bauer, F. C. Daffin, S. J. Gaff, C. K. Gelbke, T. Glasmacher, E. Gualtieri, S. Hannuschke, M. J. Huang, G. J. Kunde, R. Lacey, T. Li, M. A. Lisa, W. J. Llope, W. G. Lynch, L. Martin, C. P. Montoya, R. Pak, Graham F. Peaslee, S. Pratt, C. Schwarz, N. Stone, M. B. Tsang, A. M. Vander Molen, G. D. Westfall, J. Yee, S. J. Yennello
Faculty Publications
Two-proton correlation functions for central collisions of 36Ar+45Sc at E/A=80, 120, and 160 MeV are compared to calculations with the Boltzmann-Uehling-Uhlenbeck (BUU) transport model. Agreement is found at E/A=80MeV, but the model predicts too large correlations at E/A=120 and 160 MeV. The discrepancy may be due to delayed emission of protons from particle-unstable states not modeled in BUU.
Assessing The Evolutionary Nature Of Multifragment Decay, E. Cornell, T. M. Hamilton, D. Fox, Y. Lou, R. T. De Souza, M. J. Huang, W. C. Hsi, C. Schwarz, C. Williams, D. R. Bowman, J. Dinius, C. K. Gelbke, T. Glasmacher, D. O. Handzy, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, L. Phair, M. B. Tsang, G. Vanburen, R. J. Charity, L. G. Sobotka, W. A. Friedman
Assessing The Evolutionary Nature Of Multifragment Decay, E. Cornell, T. M. Hamilton, D. Fox, Y. Lou, R. T. De Souza, M. J. Huang, W. C. Hsi, C. Schwarz, C. Williams, D. R. Bowman, J. Dinius, C. K. Gelbke, T. Glasmacher, D. O. Handzy, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, L. Phair, M. B. Tsang, G. Vanburen, R. J. Charity, L. G. Sobotka, W. A. Friedman
Faculty Publications
Multifragment decays of central collisions in 84Kr+197Au at E/A=35, 55, and 70 MeV are studied. The dependence of the extracted emission time on the velocity of the fragment pair is investigated. More energetic pairs manifest a stronger Coulomb interaction, indicating emission from a source of smaller spatial-temporal extent than less energetic pairs. This trend can be understood in the context of a statistical model that allows the source characteristics to evolve as the fragments are emitted.
Space-Time Characteristics Of Fragment Emission In The E/A=30 Mev 129xe + Natcu Reaction, D. R. Bowman, N. Colonna, W. A. Friedman, L. Celano, M. D'Agostino, J. D. Dinius, A. Ferrero, C. K. Gelbke, T. Glasmacher, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, I. Iori, M. A. Lisa, W. G. Lynch, G. V. Margagliotti, P. M. Milazzo, C. P. Montoya, A. Moroni, Graham F. Peaslee, L. Phair, F. Petruzzelli, R. Scardaoni, C. Schwarz, M. B. Tsang, C. Williams
Space-Time Characteristics Of Fragment Emission In The E/A=30 Mev 129xe + Natcu Reaction, D. R. Bowman, N. Colonna, W. A. Friedman, L. Celano, M. D'Agostino, J. D. Dinius, A. Ferrero, C. K. Gelbke, T. Glasmacher, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, I. Iori, M. A. Lisa, W. G. Lynch, G. V. Margagliotti, P. M. Milazzo, C. P. Montoya, A. Moroni, Graham F. Peaslee, L. Phair, F. Petruzzelli, R. Scardaoni, C. Schwarz, M. B. Tsang, C. Williams
Faculty Publications
Intermediate-mass-fragment emission has been studied in central E/A=30 MeV Xe129+natCu reactions. The measured fragment multiplicities, reduced-velocity correlation functions, and emission velocities have been compared with schematic three-body trajectory calculations and with three statistical models with input based upon a dynamical BNV code. The statistical models which include expansion either explicitly or implicitly are able to generate a sufficient number of fragments. The three-body trajectory calculations indicate a mean emission time of ≊200 fm/c, consistent with sequential decay. Dynamical expanding-emitting source calculations predict a similar time scale for fragment emission and give satisfactory agreement with the experimental correlation functions if the …
Reducibility And Thermal Scaling Of Charge Distributions In Multifragmentation, L. Phair, K. Tso, R. Ghetti, G. J. Wozniak, L. G. Moretto, R. T. De Souza, 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
Reducibility And Thermal Scaling Of Charge Distributions In Multifragmentation, L. Phair, K. Tso, R. Ghetti, G. J. Wozniak, L. G. Moretto, R. T. De Souza, 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
A strong thermal signature is found in the charge distributions associated with multifragmentation from the reaction 36Ar+197Au at E/A=110 MeV. The n-fold charge distributions are reducible to the onefold charge distributions through a simple scaling that is dictated by fold number and charge conservation.
Poicen.Sas : Censored Poisson Regression, Joseph Hilbe, Gordon Johnston
Poicen.Sas : Censored Poisson Regression, Joseph Hilbe, Gordon Johnston
Joseph M Hilbe
SAS Macro to estimate censored Poisson data, using method of Hilbe. See Hilbe, Joseph M (2011), Negative Binomial Regression, 2nd ed (Cambridge University Press)
Space-Time Ambiguity Of Two- And Three-Fragment Reduced Velocity Correlation Functions, 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
Space-Time Ambiguity Of Two- And Three-Fragment Reduced Velocity Correlation Functions, 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
Reduced-velocity correlation functions between two and three intermediate mass fragments are compared for central Ar36+197Ar collisions at E/A=50 MeV. Previously published N-body Coulomb-trajectory calculations, capable of reproducing the measured two-fragment reduced velocity-correlation function, describe the measured three-fragment correlation function equally well. Moreover, ambiguities between source size and lifetime observed in the analysis of two-fragment correlations remain unresolved in the three-fragment correlation function.
Are Multifragment Emission Probabilities Reducible To An Elementary Binary Emission Probability, L. G. Moretto, L. Phair, K. Tso, K. Jing, G. J. Wozniak, R. T. Souza, 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
Are Multifragment Emission Probabilities Reducible To An Elementary Binary Emission Probability, L. G. Moretto, L. Phair, K. Tso, K. Jing, G. J. Wozniak, R. T. Souza, 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
Experimental intermediate-mass-fragment multiplicity distributions for the EA=80 and 110 MeV Ar36 + Au197reactions are shown to be binomial at all excitation energies. From these distributions, a single binary event probability p can be extracted that has a thermal dependence. Thus, it is inferred that multifragmentation is reducible to a combination of nearly independent emission processes. If sequential decay is assumed, the increase of p with excitation energy implies a contraction of the time scale that is qualitatively consistent with recent fragment-fragment correlation data.
Multifragmentation And Flow: Peripheral Vs. Central Collisions, J. Pochodzalla, S. Aiello, M. Begemann-Blaich, Th. Blaich, D. R. Bowman, R. J. Charity, A. Cosmo, A. Ferrero, C. K. Gelbke, W. C. Hsi, J. Hubele, G. Imme, I. Iori, J. Kempter, P. Kreutz, G. J. Kunde, W. D. Kunze, V. Lindenstruth, M. A. Lisa, W. G. Lynch, U. Lynen, M. Mang, L. G. Moretto, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilive, V. Pappalardo, Graham F. Peaslee, G. Raciti, F. Rosenberger, T. Rubehn, H. Sann, R. Scardaoni, A. Schüttauf, W. Seidei, V. Serfling
Multifragmentation And Flow: Peripheral Vs. Central Collisions, J. Pochodzalla, S. Aiello, M. Begemann-Blaich, Th. Blaich, D. R. Bowman, R. J. Charity, A. Cosmo, A. Ferrero, C. K. Gelbke, W. C. Hsi, J. Hubele, G. Imme, I. Iori, J. Kempter, P. Kreutz, G. J. Kunde, W. D. Kunze, V. Lindenstruth, M. A. Lisa, W. G. Lynch, U. Lynen, M. Mang, L. G. Moretto, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilive, V. Pappalardo, Graham F. Peaslee, G. Raciti, F. Rosenberger, T. Rubehn, H. Sann, R. Scardaoni, A. Schüttauf, W. Seidei, V. Serfling
Faculty Publications
Multifragment decays of heavy nuclei have been studied at the ALADIN spectrometer system at beam energies between 100 and 1000 MeV per nucleon. The observed fragment distributions signal a universality of spectator decays at bombarding energies . The role of the radial flow for the fragmentation process is explored by comparing fragment distributions measured for Au+Au collisions at in central collisions and at in more peripheral reactions. At both energies the maximum multiplicity of intermediate mass fragments (IMFs) normalized to the size of the decaying system is about one IMF per 30 nucleons but the element distributions show significant differences. …
Multifragment Emission Times In Xe Induced Reactions, A. Moroni, D. R. Bowman, M. Bruno, P. Buttazzo, L. Celano, N. Colonna, M. D'Agostino, J. D. Dinius, A. Ferrero, M. L. Fiandri, K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, Wen-Chien Hsi, M. Huang, I. Iori, M. Lisa, W. G. Lynch, G. V. Margagliotti, P. F. Mastinu, P. M. Milazzo, C. Montoya, Graham F. Peaslee, L. Phair, F. Petruzzelli, R. Rud, R. Scardaoni, C. Schwarz, B. Tsang, G. Vannini, C. Williams
Multifragment Emission Times In Xe Induced Reactions, A. Moroni, D. R. Bowman, M. Bruno, P. Buttazzo, L. Celano, N. Colonna, M. D'Agostino, J. D. Dinius, A. Ferrero, M. L. Fiandri, K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, Wen-Chien Hsi, M. Huang, I. Iori, M. Lisa, W. G. Lynch, G. V. Margagliotti, P. F. Mastinu, P. M. Milazzo, C. Montoya, Graham F. Peaslee, L. Phair, F. Petruzzelli, R. Rud, R. Scardaoni, C. Schwarz, B. Tsang, G. Vannini, C. Williams
Faculty Publications
Multifragment emission is studied in reactions. The emission process for central collisions occurs on a time scale of ≈ 200 fm/c at 30 MeV/n. Intermediate-mass-fragment yields, velocity correlation functions and emission velocities of Z=6 fragments are compared with predictions of statistical decay models.
Phase Coexistence In Multifragmentation?, L. G. Moretto, L. Phair, R. Ghetti, K. Tso, N. Colonna, W. Skulski, G. J. Wozniak, D. R. Bowman, N. Carlin, M. Chartier, C. K. Gelbke, W. G. Gong, W. C. Hsi, Y. D. Kim, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, C. Schwarz, R. T. De Souza, M. B. Tsang, F. Zhu
Phase Coexistence In Multifragmentation?, L. G. Moretto, L. Phair, R. Ghetti, K. Tso, N. Colonna, W. Skulski, G. J. Wozniak, D. R. Bowman, N. Carlin, M. Chartier, C. K. Gelbke, W. G. Gong, W. C. Hsi, Y. D. Kim, M. A. Lisa, W. G. Lynch, Graham F. Peaslee, C. Schwarz, R. T. De Souza, M. B. Tsang, F. Zhu
Faculty Publications
The charge ( Z) distributions from intermediate energy heavy-ion reactions depend upon the multiplicity n of intermediate mass fragments through a factor of the form e−cnZ. Experimentally c starts from zero at low values of the transverse energy Et and reaches a saturation value at high Et. In a liquid-gas phase diagram c=0 for the saturated vapor, while c>0 for the unsaturated vapor. It is suggested that in the c≈0 regime the source evaporates down to a sizable remnant, while for c>0 the source vaporizes completely. Percolation of finite systems and nuclear evaporation portray a behavior similar to …
Fragment Flow And The Multifragmentation Phase Space, G. J. Kunde, W. C. Hsi, W. D. Kunze, A. Schüttauf, A. Wörner, M. Begemann-Blaich, Th. Blaich, D. R. Bowman, R. J. Charity, A. Cosmo, A. Ferrero, C. K. Gelbke, J. Hubele, G. Imme, I. Iori, P. Kreutz, V. Lindenstruth, M. A. Lisa, W. G. Lynch, U. Lynen, M. Mang, T. Möhlenkamp, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilvie, Graham F. Peaslee, J. Pochodzalla, G. Raciti, T. Rubehn, H. Sann, W. Seidei, V. Serfling, L. G. Sobotka, J. Stroth, L. Stuttge, S. Tomasevic
Fragment Flow And The Multifragmentation Phase Space, G. J. Kunde, W. C. Hsi, W. D. Kunze, A. Schüttauf, A. Wörner, M. Begemann-Blaich, Th. Blaich, D. R. Bowman, R. J. Charity, A. Cosmo, A. Ferrero, C. K. Gelbke, J. Hubele, G. Imme, I. Iori, P. Kreutz, V. Lindenstruth, M. A. Lisa, W. G. Lynch, U. Lynen, M. Mang, T. Möhlenkamp, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilvie, Graham F. Peaslee, J. Pochodzalla, G. Raciti, T. Rubehn, H. Sann, W. Seidei, V. Serfling, L. G. Sobotka, J. Stroth, L. Stuttge, S. Tomasevic
Faculty Publications
Fragment distributions have been measured for Au + Au collisions at EA=100 and 1000 MeV. A high detection efficiency for fragments was obtained by combining the ALADIN spectrometer and the MSU-Miniball/WU-Miniwall array. At both energies the maximum multiplicity of intermediate mass fragments (IMF) normalized to the size of the decaying system is about one IMF per 30 nucleons but the element distributions show significant differences. Within a coalescence picture the suppression of heavy fragments in central collisions at EA=100 MeV may be related to a reduction of the density in momentum space which is caused by the collective expansion.
1995 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group
1995 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 1995.
1995 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
1995 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 1995.