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in creator/contributor: "Lawrence Berkeley National Laboratory. Nuclear Science Division."

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Calculation of Muon Final Probabilities After Muon-Induced Fission in Four-State Basis

Our earlier theoretical work on the relative muon capture between heavy and light fission fragments is extended by including 2p{sigma} states as well as 1s{sigma}. We calculate about 0.8% population of the 2p state in the heavy fragment with negligible change from our earlier two-state basis regarding the ls population of light and heavy fragments.

Date: May 1981

Creator: Zhong-yu, Ma; Xi-zhen, Wu; Jing-shang, Zhang; Yi-zhong, Zhuo & Rasmussen, J. O.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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JETS OF NUCLEAR MATTER FROM HIGH ENERGY HEAVY ION COLLISIONS

The nuclear fluid dynamical model with final thermal breakup is used to study the reactions {sup 20}Ne + {sup 238}U and {sup 40} Ar + {sup 40}Ca at E{sub LAB}=390 MeV/n. Calculated double differential cross sections d{sup 2}{sigma}/d{Omega}dE are in agreement with recent experimental data. It is shown that azimuthally dependent triple differential cross sections d{sup 3}{sigma}/dEd cos{theta}d{phi} yield considerably deeper insight into the collision process and allow for snapshots of the react… more

Date: November 1, 1980

Creator: Stocker, H.; Csernai, L.P.; Graebner, G.; Buchwald, G.; Kruse, H.; Cusson, R.Y. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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TABLE OF NUCLIDES

This table presents properties of nuclides, both stable and radioactive, adopted from the 7th edition of the Table of Isotopes. The data are based on experimental results reported in the literature, with the cutoff date varying from January to December, 1977. (The earliest date refers to the lightest nuclides, and vice versa.) Most mass excesses are from the 1977 Atomic Mass Evaluation, with some recent experimental values added. For a few of the very unstable nuclides for which no values were … more

Date: January 1, 1980

Creator: Shirley, V. S. & Lederer, C. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effects of particle evaporation on the angular momentum of the emitting nucleus for deep inelastic and compound nuclear reactions

A model is developed which allows one to calculate analytically the angular momentum removed, and the angular momentum misalignment created by the evaporation of light particles from an excited nucleus. The mass, temperature, and angular momentum of the emitting nucleus are explicitly considered. The formalism applies equally well to heavy ion and compound nuclear reactions.

Date: September 1, 1980

Creator: Blau, S. K. & Moretto, L. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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SEARCH FOR AN 80-ms SPONTANEOUS FISSION ACTIVITY IN BOMBARDMENTS OF 249Bk WITH 15N

A rotating drum system was used to search for an 80-ms spontaneous fission (sf) activity in the reaction of {sup 15}N with {sup 249}Bk. No such activity was found beyond a cross section limit of 0.3 {+-} 0.3 nb. A sf activity with a half-life of about 20 ms and a formation cross section of 12 nb at 82 MeV was observed. The identity of this activity has not been determined.

Date: January 1, 1980

Creator: Nitschke, J.M.; Fowler, M.; Ghiorso, A.; Leber, R. E.; Nurmia, M. J.; Somerville, L. P. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Production and decay of element 114: high cross sections and the new nucleus 277Hs

The fusion-evaporation reaction {sup 244}Pu({sup 48}Ca,3-4n){sup 288,289}114 was studied at the new gas-filled recoil separator TASCA. Thirteen correlated decay chains were observed and assigned to the production and decay of {sup 288,289}114. At a compound nucleus excitation energy of E* = 39.8-43.9 MeV, the 4n evaporation channel cross section was 9.8{sub -3.1}{sup +3.9} pb. At E* = 36.1-39.5 MeV, that of the 3n evaporation channel was 8.0{sub -4.5}{sup +7.4} pb. In one of the 3n evaporation … more

Date: December 22, 2009

Creator: Dullmann, Ch. E.; Schadel, M.; Yakushev, A.; Turler, A.; Eberhardt, K.; Kratz, J. V. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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DECAYS OF THE Tz = -2 NUCLEI 20Mg, 24Si AND 36Ca

Beta-delayed protons have been observed from the decays of the mass separated T{sub z} = -2 nuclides {sup 20}Mg, {sup 24}Si, and {sup 36}Ca. From these proton spectra the mass excesses of the lowest T = 2 states in the T{sub z} = -1 nuclei {sup 20}Na, {sup 24}Al, and {sup 36}K are determined to be 13420 {+-} 50 keV ({sup 20}Na), 5903 {+-} 9 keV ({sup 24}Al), and - 13168 {+-} 22 keV ({sup 36}K). The complete A = 20, 24, and 36 isospin quintets have all their members bound against isospin allowed… more

Date: June 1, 1980

Creator: Aysto, J.; Cable, M. D.; Parry, R. F.; Wouters, J. M.; Moltz, D. M. & Cerny, Joseph

Item Type: Article

Partner: UNT Libraries Government Documents Department

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INVESTIGATION OF THE (10B,6Li* (3+, 2.18 MeV)) REACTION AS A METHOD FOR alpha-CLUSTER TRANSFER STUDIES

The four-nucleon transfer reaction {sup 12}C({sup 10}B, {sup 6}Li*(2.18 MeV)) {sup 16}O has been studied at 68 MeV by coincidence measurement of the d + {alpha} breakup particles. The reaction is quite selective as is observed in other established {alpha}-transfer reactions.

Date: July 1, 1980

Creator: Bice, A. N.; Shotter, A. C.; Stahel, D. P. & Cerny, Joseph

Item Type: Article

Partner: UNT Libraries Government Documents Department

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ANOMALOUS REACTION MEAN FREE PATHS OF NUCLEAR PROJECTILE FRAGMENTS FROM HEAVY ION COLLISIONS AT 2 AGeV

We present in detail the description and the analysis of two independent experiments using Bevalac beams of {sup 16}O and {sup 56}Fe. From their results it is concluded that the reaction mean free paths of relativistic projectile fragments, 3 {<=} Z {<=} 26, are shorter for a few centimeters after emission than at large distances where they are compatible with values predicted from experiments on beam nuclei. The probability that this effect is due to a statistical fluctuation is <10{s… more

Date: August 1, 1982

Creator: Friedlander, E. M.; Gimpel, R. W.; Heckman, H. H.; Karant, Y. J.; Judek, B. & Ganssauge, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement of the 208Pb(52Cr, n)259Sg Excitation Function

The excitation function for the 208Pb(52Cr, n)259Sg reaction has been measured using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. The maximum cross section of pb is observed at a center-of-target laboratory-frame energy of 253.0 MeV. In total, 25 decay chains originating from 259Sg were observed and the measured decay properties are in good agreement with previous reports. In addition, a partial excitation function for the 208Pb(52Cr, 2n)2… more

Date: March 19, 2010

Creator: Folden, C. M., III; Dragojevic, I.; Dullmann, Ch. E.; Eichler, R.; Garcia, M. A.; Gates, J. M. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Entrance-channel effects in odd-Z tranactinide compound nucleus reactions

Swiatecki, Siwek-Wilczynska, and Wilczynski's 'Fusion By Diffusion' description [1] of transactinide (TAN) compound nucleus (CN) formation utilizes a three-step model. The first step is the 'sticking', or capture, which can be calculated relatively accurately. The second step is the probability for the formation of a CN by 'diffusion' analogous to that of Brownian motion. Lastly, there exists the probability of the CN 'surviving' deexcitation by neutron emission, which competes with fission and… more

Date: September 1, 2007

Creator: Nelson, S. L.; Gregorich, K. E.; Dragojevic, I.; Dullmann, Ch. E.; Eichler, R.; Folden, C. M., III et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Influence of projectile neutron number on cross section in cold fusion reactions

Elements 107-112 [1,2] have been discovered in reactions between {sup 208}Pb or {sup 209}Bi targets and projectiles ranging from {sup 54}Cr through {sup 70}Zn. In such reactions, the compound nucleus can be formed at excitation energies as low as {approx}12 MeV, thus this type of reaction has been referred to as 'cold fusion'. The study of cold fusion reactions is an indispensable approach to gaining a better understanding of heavy element formation and decay. A theoretical model that successfu… more

Date: September 1, 2007

Creator: Dragojevic, Irena; Dragojevic, I.; Gregorich, K. E.; Dullmann, Ch. E.; Folden, C. M., III; Garcia, M. A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Synthesis of rutherfordium isotopes in the 238U(26Mg, xn)264-xRf reaction and study of their decay properties

Isotopes of rutherfordium (258-261Rf) were produced in irradiations of 238U targets with 26Mg beams. Excitation functions were measured for the 4n, 5n and 6n exit channels. Production of 261Rf in the 3n exit channel with a cross section of 28+92-26 pb was observed. Alpha decay of 258Rf was observed for the first time with an alpha-particle energy of 9.05+-0.03 MeV and an alpha/total decay branching ratio of 0.31+-0.11. In 259Rf, the electron capture/total decay branching ratio was measured to b… more

Date: January 15, 2008

Creator: Gates, Jacklyn M.; Gates, J. M.; Garcia, M. A.; Gregorich, K. E.; Dullmann, Ch. E.; Dragojevic, I. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Comparison of reactions for the production of 258,257Db: 208Pb(51V,xn) and 209Bi(50Ti,xn)

Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070+1100/-760 pb was measured at an excitation energy of 16.0 +- 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660+450/-370 pb was measured at 22.0 +- 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480+1750/-1370 pb at an excitation en… more

Date: September 29, 2008

Creator: Gates, Jacklyn M.; Nelson, Sarah L.; Gregorich, Kenneth E.; Dragojevic, Irena; Dullmann, Christoph E.; Ellison, Paul A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department