C.M. Baglin, E. Browne, S.Y. Chu, J.M. Dairiki (to 7/97), R.B. Firestone, B. Singh (to 10/97).
 

Report prepared for the December 1998 IAEA Advisory Group Meeting on Coordination of the International Network of Nuclear Structure and Decay Data Evaluators.

The Isotopes Project is heavily committed to both the Evaluation and Dissemination aspects of nuclear structure and decay data; these activities are reported in separate sections of this report.
 
 

NUCLEAR STRUCTURE AND DECAY EVALUATION

October 1996 - October 1998
 
 

Mass Chain Responsibility
    Permanent (43 chains): A = 81, 83, 89-93, 167-194, 206, 210-212, 215, 219, 223, 227
    Temporary (11 chains): A = 59, 76, 79, 80, >266
 

PERSONNEL

The group's data evaluation effort has ranged from 2.4 to 2.1 FTE during the period covered by this report. In addition, two guests have spent sabbatical leave with the Isotopes Project: Professor Jacob Gilat (Israel) and Professor Alice Wu (Taiwan). Both are experimentalists (high spin physics and nuclear astrophysics, respectively) and both were interested in spending part of their time on evaluation. Dr. Wu has already prepared ²⁶Al and ⁵⁷Ni decay evaluations, and Dr. Gilat worked on the A³ 266 chains. An ongoing collaboration with Gabor Molnar (Hungary) is concerned with the preparation of evaluated (n,g) data. The group is also indebted to Jean Zipkin for the preparation of many high-spin or (n,g) data sets.

EVALUATION ACCOMPLISHMENTS (since last Meeting)

 Mass Chains

    Submitted: 89 (75% LBNL), 90, 91, 93, 135 (75% LBNL), 176, 192, 206
    Published: 81, 89 (75% LBNL), 90, 93, 135 (75% LBNL), 176, 186, 192, 194
    In Progress: 167, 174
                        A>265 (8 chains; all of the 11 nuclides in these chains have been evaluated, but formatting has not yet been completed).
 
•  Nuclides

                Nuclides Far from Stability*

                Decays of Astrophysical Interest

                                                    ⁴⁴Ti, ⁵⁷Ni (in review)

                Spontaneous Fission Decay Data Sets (21 nuclides; added to ENSDF)

                                        I: A=135

                                        Xe: A=140, 141, 142, 143, 144

                                        Ba: A=140, 142, 143, 144, 145, 146, 147, 148

                                        La: A=145, 147, 148

                                        Ce: A=149

                                        Nd: A=151, 15

                High Spin

          · Superdeformed nuclides (LBNL-McMaster Collaboration): the July 1997 annual update of all SD data ( ~70 nuclides)
              was completed and submitted for inclusion in ENSDF.

· A=211 high spin update added to ENSDF.

                Miscellaneous Decay Data Sets (36 nuclides added to ENSDF)

                a decay 9 nuclides         11 data sets

                b decay 7 nuclides         -

                e decay 14 nuclides       15 data sets

                p decay 2 nuclides         3 data sets

                ep, bn decays                4 nuclides -

                                    Decay Data Collaboration Nuclides:

COMPILATION

During 1996 and 1997, in response to high-spin researchers' desire for more timely access to data sets from recent publications, 208 high-spin data sets were compiled in ENSDF format by Jean Zipkin, and promptly posted on the Web. These data sets, along with 113 high-spin data sets (accessible on-line from NNDC) compiled in 1995 in conjunction with the preparation of the 8th Edition of the Table of Isotopes, have been transmitted to Balraj Singh (McMaster University) for his consideration for inclusion in a new high-spin data base containing compiled (i.e., unevaluated) high-spin data sets. A significant number of these data sets contain information which has not yet been evaluated and added to ENSDF.
 

PC SOFTWARE FOR EVALUATION
 

With the impending demise of LBNL’s central VAX VMS computers, PC (Windows 95/NT, Fortran) versions of five programs originally written for use on that system have been created and also made available on the Web. These are BALANCE 2.0, ENDIT 2.0 (ENSDF file line editor), Betas 2.0, XICC 2.0 and LogFT 2.0 (interactive calculation of Logft and EC/B+ values). Preparation of a PC version of the program GAMUT has commenced.
 

1. World Wide Web

The Isotopes Project has continued to expand its data dissemination efforts on the WWW. Linked home pages for access to data from the Table of Isotopes, nuclear astrophysics, high-spin nuclear structure, radioactive decay, atomic masses, capture gamma, fission, and other topics have been developed. These home pages can be accessed from the WWW at http://ie.lbl.gov/toi.html. Data are provided in text, Postscript, and Portable Document Format. Approximately 4500 separate users per month submitted over 860,000 data requests last year. The usage since 1995 is summarized in Figure 1.
 

 
1.1. Astrophysics Home Page

The Nuclear Astrophysics home page at http://ie.lbl.gov/astro.html includes a comprehensive bibliography of references to literature of interest to researchers in the nuclear astrophysics community. Links are provided when the reference or data is available in electronic form. Stellar nucleosynthesis data from Hoffman and Woosley, Thielemann et al., and others are available in text and Postscript format from the home page. Approximately 600 users access this page each month.

1.2. High-Spin and Nuclear Structure Home Page

An electronic edition of the Table of Superdeformed Nuclear Bands and Fission Isomers is available from the High-Spin and Nuclear Structure home page at http://ie.lbl.gov/hspin.html. This home page also provides reference lists and links to information of interest to nuclear structure researchers. About 400 users access this page each month.

1.3. Decay Data Home Page

The decay data home page at http://ie.lbl.gov/decay.html provides summary mass-chain decay schemes and nuclear charts from the Table of Isotopes; energy-ordered tables of gamma rays from radioactive decay; alpha and gamma energy and intensity standards; data from the 1986 edition of the Table of Radioactive Isotopes; and links to information of interest to users of decay data. Approximately 600 users access this page each month.

1.4. Atomic Masses Home Page

The atomic mass home page at http://ie.lbl.gov/toimass.html provides access to the experimental atomic mass tables of Audi et al and 14 calculated mass tables. Approximately 700 users access this page each month.

1.5. Thermal Neutron Capture Home Page

The Thermal Neutron Capture home page at http://ie.lbl.gov/ng.html was developed jointly by the Isotopes Project and the Institute for Isotope and Surface Chemistry, Hungary. Lone et al gamma-ray yield data, ENSDF (n,g) E=Thermal data for A>44, LBNL/Hungary (n,g) compilation for A<45, isotopic abundances, and thermal neutron cross sections are available from this site. Approximately 300 users access this page each month.

1.6. Fission Home Page

The Fission home page at http://ie.lbl.gov/fission.html contains fission yields compiled by England and Rider and spontaneous fission data from ENSDF.. Approximately 200 users access this page each month.

1.7. Other Data

Additional home pages for atomic data, elemental data, education, nuclear moments, interaction of radiation with matter are also available. These pages attract over 2000 users per month.

2. Isotope Explorer

http://ie.lbl.gov/isoexpl/isoexpl.htm. In addition, it is available on the Table of Isotopes CD-ROM. About 1300 users express interest in this program each month. ENSDF datasets for about 300,000 isotopes were downloaded by Isotope Explorer users during the past year. Month-to-month usage fluctuates substantially. Isotope Explorer 2.0 was released for Windows 95/NT in 1998 replacing VuENSDF. The program can download ENSDF data from the Isotopes Project Server, or the Table of Isotopes CD-ROM. The ENSDF format data can be displayed as level scheme drawings, Nuclear Data Sheet style tables, plots, or on nuclear charts. The data can be selected by level properties (E, JPI, half-life), gamma-ray coincidence relationships, or nuclear structure and band assignments. Tables can be displayed with complete comments and may be sorted by column. The keyword abstracts for the references can also be retrieved by Isotope Explorer from the WWW or Table of Isotopes CD-ROM and displayed. Print preview and print capabilities are available for all Isotope Explorer display modes.

Experimental and theoretical chart databases, containing a variety of ground-state and isomer properties, are provided with Isotope Explorer for the nuclear chart mode. Users can also easily generate personal databases for use with the chart. These data can be displayed on a chart colored by the magnitude of selected properties. A script language is provided to perform calculations with the chart databases and to search the ENSDF file by data property. Data on the chart are linked directly to ENSDF, when applicable, and the underlying ENSDF datasets can be accessed with the mouse. A small navigation window is provided to assist users in moving about the chart. Isotope Explorer 2.0, a tour of its capabilities, and the user manual can be downloaded from the WWW. Usage since 1996 is summarized in Figure 2.
 

3. LBNL/Lund Isotope Explorer NSR Server

The LBNL/Lund Isotope Explorer NSR Server on the WWW supersedes the Nuclear Data and References CD-ROM in 1996. This information can be accessed from mirror servers at LBNL (http://128.3.5.61:6023/welcome.htm), and Lund (http://130.235.93.31:6023/welcome.htm). References from the Nuclear Science Reference file can be selected by any combination of author, nuclide, keynumber, data, reaction, keyword, and data type. References satisfying the selection criteria are selected by the Isotopes Project or Lund server and the keyword abstracts are returned to the user and displayed. Currently aver 3000 reference requests are processed each month. A sample Isotope Explorer NSR Server window is shown in Figure 3.
 
 

                                                            Figure 3. Sample Nuclear Science Reference Search

4. LBNL/Lund WWW Table of Radioactive Isotopes

The LBNL/Lund Table of Radioactive Isotopes on he WWW can be accessed at http://nucleardata.nuclear.lu.se/Database/toi. Gamma-ray and alpha-particle data from ENSDF and the Table of Isotopes can be searched by combination of energy and nuclide range. Additional information, including x-ray, Auger, and continuous radiations, will be added in 1999. This service has been provided for about 6 months with usage gaining rapidly. Nearly 8000 users accessed the Table of Radioactive Isotopes in September, 1998.
 

PUBLICATIONS and INVITED TALKS (since last Meeting)

Mass Chain or Nuclide Evaluations (hard copy)

Nuclear Data Sheets for A=194, E. Browne and B. Singh, Nuclear Data Sheets 79, 277 (1996).
Nuclear Data Sheets for A=81, Coral M. Baglin, Nuclear Data Sheets 79, 447 (1996).
Nuclear Data Sheets for A=93, Coral M. Baglin, Nuclear Data Sheets 80, 1 (1997).
Nuclear Data Sheets for A=186, Coral M. Baglin, Nuclear Data Sheets 82, 1 (1997).
Nuclear Data Sheets for A=90, E. Browne, Nuclear Data Sheets 82, 379 (1997).
Nuclear Data Sheets for A=135, Yu.V. Sergeenkov and B. Singh, Nuclear Data Sheets 84,115 (1998).
Nuclear Data Sheets for ¹⁷⁰Ta, Coral M. Baglin, Nuclear Data Sheets 84, 323 (1998).
Nuclear Data Sheets for A=176, E. Browne and J. Huo, Nuclear Data Sheets 84, 337 (1998).
Nuclear Data Sheets for A=192, Coral M. Baglin, Nuclear Data Sheets 84, 717 (1998).
Nuclear Data Sheets for A=89, B. Singh, Nuclear Data Sheets 85, 1 (1998).

CD-ROM Publication Based on ENSDF and NSR

Table of Isotopes, 8th Edition, CD-ROM Update, John Wiley & Sons, Inc., NY, R.B. Firestone, Coral M. Baglin, S.Y. Frank Chu, April 1998.

Invited Talks on Nuclear Data

"Future Directions in Nuclear Data Publication", R.B. Firestone, S.Y.F. Chu, L.P. Ekstrøm, and H. Nordberg, Proceedings of 9th International Symposium on Capture Gamma-ray Spectroscopy and Related Topics, Budapest, Hungary, 1996 (to be published)

"The Table of Isotopes -- 8th Edition and Beyond", R.B. Firestone, Joint American Nuclear Society and European Nuclear Society 1996 International Conference, Washington, DC, November, 1996, Transactions 375, 117 (1996).

"Methods and Procedures for Evaluating Radioactive Decay Data", E. Browne, Joint American Nuclear Society and European Nuclear Society 1996 International Conference, Washington, DC, November, 1996, Transactions 375, 116 (1996).

"Exploring the Isotopes", R.B. Firestone, S.Y.F. Chu, and H. Nordberg, American Chemical Society, San Francisco, CA, April 15, 1997.

"High-Spin Nuclear Structure Data on the Internet, B. Singh and R.B. Firestone, American Chemical Society, San Francisco, CA, April 15, 1997.

"Evaluation of Decay Data: Quality and Uniformity", E. Browne and R.G. Helmer, American Chemical Society, San Francisco, CA, April 15, 1997.

"Nuclear Astrophysics Data on the Internet", E.B. Norman, 2nd Oak Ridge Symposium on Atomic and Nuclear Astrophysics, Oak Ridge, TN, Dec. 4, 1997 (in press).

"Nuclear Astrophysics Data on the Internet", R.B. Firestone, S.Y.F. Chu and E.B. Norman, Nuclei in the Cosmos 98, 6-11 July 1998, Volos, Greece (in press).

Research Publications:

Identification of Gamma Transitions in ¹⁴⁷Ba, ¹⁴⁹Ce, and ^151,153Nd, B.R.S. Babu, S.J. Zhu, A.V. Ramayya, J.H. Hamilton, S.Y. Chu et al., Phys. Rev. C54, 568 (1996)

Observation of Cold Fission in ²⁴²Pu Spontaneous Fission, Y.X. Dardenne, R. Aryaeinejad, S.J. Asztalos, B.R.S. Babu, K. Butler-Moore, S.Y. Chu et al., Phys. Rev. C54, 206 (1996).

Probes of Pairing Correlations by Heavy-Ion Two-Neutron Transfer Reactions, J.O. Rasmussen, S.Y. Chu, M.A. Stoyer, L.F. Canto, R. Donangelo and P. Ring, Phys. Rep. 264, 325 (1996).

Galactic Confinement Time of Iron-Group Cosmic Rays Derived from the ⁵⁴Mn Chronometer,
K. Zaerpoor, Y.D. Chan, E.B. Norman et al., Phys. Rev. Lett. 79, 4306 (1997).

Reflection Asymmetric Shapes in the Neutron-Rich ^140,143Ba Isotopes, S.-Z. Zhu, M.-G. Wang, S.Y. Chu et al., Chin. Phys. Lett. 14, 569 (1997).

High Spin Octupole Correlations in the N=85, ¹³⁹Xe and ¹⁴¹Ba Isotones, S.J. Zhu, J.H. Hamilton, S.Y. Chu et al., J. Phys. (London) G23, L77 (1997).

Angular Momenta of Fragments in the ²⁵²Cf Spontaneous Fission, G.M. Ter-Akopian, Yu.Ts. Oganessian, S.Y. Chu et al., Bull. Russ. Acad. Sci. Phys. 61, 149 (1997).

Cold Binary and Ternary Fragmentations in Spontaneous Fission of ²⁵²Cf, A.V. Ramayya, J.H. Hamilton, S.Y. Chu et al., Nuovo Cim. 110A, 1073 (1997).

Identification of the n3/2^-[521] Band in ¹⁵³Nd and the g-Transitions in ¹⁴⁹Nd, J.K. Hwang, A.V. Ramayya, S.Y. Chu et al., Int. J. Mod. Phys. E6, 331 (1997).

Yields of Fragment Pairs and Other Characteristics of Spontaneous ²⁵²Cf Fission, G.M. Ter-Akopian, Yu.Ts. Oganessian, S.Y. Chu et al., Bull. Russ. Acad. Sci. Phys. 61, 587 (1997).

On the Half-Life of ⁴⁴Ti, E.B. Norman, E. Browne, Y.D. Chan, I.D. Goldman, R.-M. Larimer, K.T. Lesko, M. Nelson, F.E. Wietfeldt and I. Zlimen, Nucl. Phys. A621, 92c (1997).

Radioisotope Yields from 1.85-GeV Protons on Mo and 1.85- and 5.0-GeV Protons on Te, D.W. Bardayan, M.T.F. da Cruz, M.M. Hindi, E.B. Norman et al., Phys. Rev. C55, 820 (1997).

a-Particle Induced g-Ray Transitions in Light Elements, R.K. Heaton, H.W. Lee, B.C. Robertson, E.B. Norman, K.T. Lesko and B. Sur, Phys. Rev. C56, 922 (1997).

Identification of ¹⁰⁹Mo and Possible Octupole Correlations in ^107,109Mo, J.K. Hwang, A.V. Ramayya, S.Y. Chu, J. Gilat et al., Phys. Rev. C56, 1344 (1997).

Weak Gamma Rays from the Electron-Capture Decay of ¹⁹⁴Au, R.R.P. Teixeira, I.D. Goldman, E. Browne, A.O. Macchiavelli, E.B. Norman et al., Phys. Rev. C56, 2320 (1997).

Half-Life of ⁴⁴Ti, E.B. Norman, E. Browne, Y.D. Chan, I.D. Goldman, R.-M. Larimer, K.T. Lesko, M. Nelson, F.E. Wietfeldt, and I. Zlimen, Phys. Rev. C57, 2010 (1998).

Identification of New Negative-Parity Levels in ^152,154Nd, X.Q. Zhang, J.H. Hamilton, J. Gilat et al., Phys. Rev. C57, 2040 (1998).

Cross Sections for the ¹⁷O(n,p)¹⁷N and ¹⁷O(n,d)¹⁶N Reactions at 14 MeV, E.B. Norman and B. Sur, Phys. Rev. C57, 2043 (1998).

Cosmic-Ray Half-Life of ¹⁴⁴Pm, K. Zaerpoor, E.B. Norman et al., Phys. Rev. C57, 2046 (1998).

Identification of the g Transitions in Tc and Cs Products of ²⁵²Cf Fission and Possible (7/2)⁺[413] Bands in ^105-109Tc Isotopes, J.K. Hwang, J. Gilat, S.Y. Chu, et al., Phys. Rev. C57, 2250 (1998).

Cold (Neutronless) a Ternary Fission of ²⁵²Cf, A.V. Ramayya, J.H. Hamilton, S.Y. Chu et al., Phys. Rev. C57, 2370 (1998).

Close Doublet Structures in ¹⁰³Mo, ^109,111Ru and Neighbours: Rotation-alignment for the Half-filled h11/2 subshell ? , J.K. Hwang, A.V. Ramayya, S.Y. Chu, J. Gilat et al., J. Phys. (London) G24, L9 (1998).

Electron Capture Decay of ¹¹⁶In and Nuclear Double Beta Decays, M. Bhattacharya, A. Garcia, M.M. Hindi, E.B. Norman, O. Civitarese, J. Suhonen et al., Phys. Rev. C58, 1247 (1998).

Search for Strange Matter by Heavy Ion Activation, M. C. P. Isaac, E. B. Norman, L. S. Schroeder, F. S. Stephens et al., Phys. Rev. Lett. 81, 2416 (1998).

Neutron Capture Cross Section of ⁴⁴Ti, R. Ejnisman, I. D. Goldman, K. S. Krane, E.B. Norman et al., Phys. Rev. C58, 2531 (1998).