Ground state half life. Ground state half life 34 Cl 32.2 minutes 1.53 seconds. 169 Re 16 seconds 8.1 seconds. 177 Lu days 6.

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1 RDCH 70 Name: Quiz ssigned 5 Sep, Due 7 Sep Chart of the nuclides (up to and including page - of the lecture notes) Use the chart of the nuclides, the readings on the chart of the nuclides, table of the isotopes, and web links from lecture to answer the following questions.. (0 Points)Using the chart of the nuclides find 4 isotopes where the metastable state is longer lived that the ground state. Examples are below Isotope Metastable Ground state Isotope Metastable Ground state 4 Cl. minutes.5 seconds 69 Re 6 seconds 8. seconds 4 Sc.0 minutes 68 ms 77 Lu 60.7 days 6.65 days 44 Sc.44 days.9 hours 80 Ta >.E5 8.5 hours years 50 Mn.74 minutes 8. ms 84 Re 65 days 8 days 54 Co.46 minutes 9. ms 86 Re E5 years.78 days 80 Br 4.4 hours Ir 4e years 7.8 days minutes 8 Se 57. minutes 8.5 minutes 95 Tc 6 days 0.0 hours 0 Rh.74 years 07 days 04 Rh 4.6 minutes 4. seconds 06 Rh.8 hours 9.9 seconds 06 g 8.8 d 4.0 m 08 g 48 years.9 minutes 0 g 49.8 days 4.6 seconds 4 In 49.5 days.98 minutes 5 Cd 44.6 days.8 days 8 Sb 5 hours.6 minutes 9 Te 4.69 days 6.0 hours Te 64 days 9. days Sn 44 years.8 days Te.6 days 5.0 minutes 48 Pm 4. days 5.7 days 6 Ho. hours 5 minutes 66 Ho 00 years.8 days 94 Ir 7 days 9. hours 95 Hg.7 days 0.5 hours 95 Ir.9 hours.5 hours 00 u 8.7 hours 48.4 minutes 0 Bi E6 years 5.0 days Po 45 seconds 0.98 microseconds c 6 seconds 5 seconds 4 m 4 years 6.0 hours 48 Bk >9 years.7 hours 65 Sg 8 seconds 8 seconds

2 . (0 Points) The cross section data generally have two values. s an example the cross section data the absorption of a neutron and emission of a photon for 47 Nd is =4E, E Why are there two values and what is the cross section unit. Define the different types of cross sections presented by the data. The cross section data is for the thermal neutron and resonance integral for the production of 48 Nd. The resonance integral is the reaction over a large energy range above thermal energy. The data is presented as 4E, 4E in barns, where a barn= 0-4 cm. The data represents the following: 47 Nd(n, )X Thermal cross Resonance section (barns) Integral (barns) 48Nd 4E 4E. (5 Points) Name 5 elements lighter than uranium that were found during the discovery of fission. From page in the chart of the nuclides elements found during fission include barium, lanthanum, cerium, molybdenum, rubidium, antimony, and iodine. 4. (0 Points) Provide 5 elements that have at least 5 metastable isotopes? re there any trends in the population of isotopes with metastable states? (consider the number of neutrons and protons) partial list includes: Os, Hf, Lu, Ir, u, Co, Br, Nb, Ce, Se, Y, Rh, Tc, g, Ba, Cs, Sb, In, Sn, Te, Rb, Po Metastable isotopes tend to be heavy and have an unpaired nucleon. The lightest metastable isotopes are 4m Na, 6m l, 4m Cl, 8m Cl and 8m K, all of which have an odd number of protons and neutrons. Cobalt (Z=7) is the lightest element with at least 5 metastable states. Elements with even Z (i.e., Ge with Z=) that have at least 5 metastable states manifest the metastable states with odd N. For Ge the metastable isotopes are 7m Ge, 75m Ge, 77m Ge, 79m Ge, and 8m Ge. The generalized trends for metastable isotopes are that they are heavy (Z above 6), and have at least one unpaired nucleon, primarily the proton. Even-even metastable isotopes tend to be populated by beta decay. 5. (0 Points) Provide the cumulative fission yields for the isobars listed below. U 5 U 9 Pu

3 Fission Yield Ratio 5 U/ 9 Pu Fission Yield % 6. (5 Points) Plot the ratio of 5 U cumulative fission yield to 9 Pu cumulative fission yield for and (Use plotting software, provide on separate page). What are the differences between the higher (5 50) and lower (90 05) set? What accounts for this difference? U FY 9Pu FY U/9Pu FY

4 What are the differences between the higher and lower set? What accounts for this difference? The ratio of the higher set is close to ; there is not a large difference in the cumulative fission product yield for these isotopes for the fission of 5 U and 9 Pu. The main difference in the cumulative fission yields for 5 U and 9 Pu is in the lower area, with a large ratio near 90 and a small ratio above 05. The similarity in the high set is driven by the doubly magic Sn (Z=50, N=8). This enhanced stability leads a tendency for the formation of isotopes in this region. 7. (5 Points) Describe the cross section data presented for 97 u. The cross section data is for the thermal neutron and resonance integral for the production of 98m u and 98 u. The resonance integral is the reaction over a large energy range above thermal energy. The data is presented as ( ), 55E in barns. The data represents the following: 97 u(n, )X Thermal cross section Resonance Integral 98mu 0 98u E 8. (0 Points) Provide the main gamma decay energy and the gamma decay intensity for the following isotopes Isotope Main gamma decay energy (kev) Gamma Intensity (%) 56 Ni 58.4, , Co.5, , Sb 685.7, , Cs Re 6., 46.5., m (5 Points) Where was the location of the first man-made reactor? Stagg field, University of Chicago under the direction of Enrico Fermi 4

5 0. (0 Points) Provide the spin, parity, and half-life for the isotopes below Isotope Spin Parity Half-life 08 Pb 0 + Stable 07 Rh 7/ +.7 minutes 99 Tc 9/ +.E5 years 48m Pm 6-4. days 6 Dy 0 + Stable 55 Fm 7/ + 0. hour 5