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Brian Flowers -

Brian Flowers -. Sir Brian Hilton Flowers Lord Flowers of Queen's Gate. born 13 Sept.1924 (died 25 June 2010) the son of a noted Welch preacher, the Rev. Harold Flowers and his wife Marian in Blackburn, Lancashire. He took physics and electronics in Cambridge.

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Brian Flowers -

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  1. Brian Flowers - Sir Brian Hilton Flowers Lord Flowers of Queen's Gate born 13 Sept.1924 (died 25 June 2010) the son of a noted Welch preacher, the Rev. Harold Flowers and his wife Marian in Blackburn, Lancashire

  2. He took physics and electronics in Cambridge Before he was 20he was recruited by John Cockroftto the Anglo – Canadion atomic bomb project at Chalk River, Ontario

  3. Cockroft brought him back to Brittain to work in Otto Frisch’s group of the Atomic Research Establishment at Harward in Fuch’s theoretical section • in 1946

  4. in 1950 Fuchs was arrested as a Soviet agent and Flowers went to Birmingham Universityto work under Rudof Peiersls

  5. he was appointed professor of theoretical physics in Manchester University at the age of 34 • in 1958 (till 1967) • in 1961 elected as a fellow of the Royal Society (FRS) at the age of 36

  6. in 1964 Chairman of the Science Research Council (SRC) • in 1973 (till 1985) Rector of Imperial College of London University

  7. in 1985 - 1990 Vice-Chancellor of London University • in 1969 He was knighted(Sir Brian Flowers) • in 1979 Lord Flowers of Queen’s Gate

  8. President of the Institute of Physics • President of the European Science Foundation • President of the National Society for Clean Air • President of the Parliamentary Scientific Committee • Chairman of the House of Lords Selected Committee on Science and Technology • Chairman of the Royal Commission on Environmental Pollution • Officier of the (France) Legion d’Honneur Meantime

  9. B.H Flowers Group – theory classification of nuclear shell states Link between results (a and b) (a - 1952) (b - 1964) , Proc. Roy. Soc. A 210 (1951) 197 Proc. Roy. Soc. A 212 (1952) 248 B.H Flowers

  10. and (b – 1964) B.H Flowers and S. Szpikowski , Proc. Phys. Soc. 84 (1964) 193 , Proc. Phys. Soc. 84 (1964) 673

  11. n (a) Configuration of N states on j level for example: , n =8 , N=12.870 Group structure

  12. Infinitesimal operators • Resulting states

  13. (b) Quasi - spin classification

  14. In the new basis – diagonalization of the pairing Hamiltonian:

  15. Moreover: n the classification of l nuclear configurations was also given in the new qausi – spin classification:

  16. with energy diagonalization:

  17. born 17 July 1929 (died 21 October 2008) in Gospart, Hampshire of an engine driver and schoolteacher James Philip Elliott

  18. He read mathematics at UniversityCollege Southampton, graduating in 1949 and remaining to do postgraduate work He obtained his doctorate in theoretical nuclear physics under the supervision of Hermann Jahn. He joined the theoretical division of Atomic Energy Research Establishment in Harwell when Dr Brian (later Lord) Flowers was appointed director.

  19. After a year in the USA at the University of Rochester he returned to Southampton. In 1962 he moved to the School of Mathematical and Physical Sciences at the new University of Sussex , Brighton, remaining there until his retirement in 1994.

  20. Phil Elliott achieved global recognition in 1958 with the publication of an application of the symmetry group SU (3) to nuclear structure. This work become one of the most frequently cited references in the field. In 1998 – in the 40th anniversary of the SU (3) model – a nuclear physics conferenceheld in Brighton with over 100 delegates from over the world.

  21. The conference began with keynote talks by Phil Elliott himself and Akito Arima on the origin and development of the SU(3) model. The advent of the Interacting Boson Model of nuclear structure introduced by Arima and Iachello gave his research new impetus in establishing a firm connection between it and more familiar shell model.

  22. This aim was achieved in series of papers in 1980’s on neutron – proton pairs and isotopic spin in collective nuclear motion. Phil Elliott was elected to the Royal Society (FRS) in 1980. In 1994 he was awarded The Rutherford medal and prize by the Institute of Physics.

  23. In 2002 the European Physical Society awarded its prestigious Lise Meitner prize jointly to Elliott and Iachello„ for their innovative applications of group theoretical methods to the understanding of atomic nuclei”.

  24. Phil Elliott • The famous SU(3) Elliott model and • (b) The Interacting Boson Model: IBM 3 • and IBM 4 • Link between (a) – 1958 and (b) – 1980: • the symmetry consideration with group • theory methods

  25. (a) , Proc. Roy. Soc. A 245 (1958) 229 , Proc. Roy. Soc. A 245 (1958) 562 J.P. Elliott (b) J.P. Elliott and A.P. Whte , Phys. Lett. 97B (1980) 169 J.P. Elliott and J.A. Evans , Phys. Lett. 101B (1981) 216 J.A. Evans, J.P. Elliott and S. Szpikowski , Nucl. Phys. A 435 (1985) 317

  26. (a) The Elliott's SU (3) Model N = 0,1,2,... = N, N-2,..., 0 or 1 For a given N there is a (N +1) (N+2) multiplet of states with the same energy .

  27. Conclusion: there must be a higher symmetry then SO (3). It is the famous Elliott’s symmetry SU (3). and

  28. Elliott proved then the nine operators H, L , and Q form a basis for Lie- algebra of the U(3) unitary group and U(3) = U(1) SU(3) (L , Q ) This is the famous Elliott’s SU(3).

  29. Immidiate application: Under the same symmetry group SU(3) we can consider the mixing configuration of states belonging to the same IR of SU(3) on different l – shells as Elliott in his original paper considered for N=2 and 2p and 1f shells.

  30. (b) Elliott invented so called Interacting Boson Model No III and No IV Main assumption of Arima and Iachello: In even nuclei for ground and low excited states nucleons form pairs coupled to lowest J only ,i.e.J=0 and J=2

  31. Then, the operators , ,and form a 36 – member set which can be considered as the infinitesimal generators of the U(6) unitary transformation group.

  32. The full application of the IBM model follows the description of different multiples of atomic nuclei with the help of symmetries starting with U(6) To make the model more realistic, Elliott introduced to IBM the isospin labels: and (T=0 is not allowed)

  33. are generators of the symmetry group U(18)> U(6) U(3) That is the starting point of the Elliott IBM 3 model Then the operators

  34. To include T=0 to bosons, Elliott introduced the intrinsic spin to bosons: and ; S=1,T=0 or S=0 T=1 The symmetry starting group, the IBM 4 model, is which is the Elliott IBM4 model

  35. With these models Elliott was able to analyse the neutron – protononlor j shellconfigurations.

  36. Thank you for your attention

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