Presentation is loading. Please wait.

Presentation is loading. Please wait.

HL-4 May 2004Kernfysica: quarks, nucleonen en kernen1 Outline lecture (HL-4) Structure of nuclei Shell structure Deformation Nuclear reactions Stripping.

Similar presentations


Presentation on theme: "HL-4 May 2004Kernfysica: quarks, nucleonen en kernen1 Outline lecture (HL-4) Structure of nuclei Shell structure Deformation Nuclear reactions Stripping."— Presentation transcript:

1 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen1 Outline lecture (HL-4) Structure of nuclei Shell structure Deformation Nuclear reactions Stripping reaction DWBA Literature: PR 16, 17

2 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen2 energy of 1. exc. state of even-even nuclei typ. J P =2 + shell and level structure determined by depth/shape of central potential, spin-orbit force, residual interaction (pairing correlations) j=l-1/2 j=l+1/2

3 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen3 single-particle levels nl j shell gaps and intruder states

4 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen4 particle- and hole-states and excitations mirror pair, hole mirror pair, nucleon isospin independence of nuclear force

5 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen5 deformed nuclei: quadrupole moments partially occupied p- and n-shells  polarized the nucleus  deformation prolate oblate

6 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen6 regions of large deformation half-full shells  deformation Hund rule for atom shells: nl subshell filling: first different orbitals l next substates m l repulsive Coulomb force favours separate orbitals

7 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen7 pairing and polarization attractive NN force favours: pairing: l 1 = l 2 ; m 1 = -m 2 ; j = 0; J P = 0 + adjacent m-substate filling overlapping adjacent m-orbitals  deformation energy levels of deformed nuclei  ellipsoidal potential shape Nilsson Parameters:  = l z  = j z

8 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen8 extended SPSM: Nilsson model single-particle motion in anisotropic oscillator field: quantum numbers N = n 3 + n   [Nn 3  ] deformation    -  3

9 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen9 deformation parameters: exp. and calc.  = exp. A even  = exp. A uneven  = calc. A uneven

10 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen10 spectroscopy through nuclear reactions stripping reaction 16 O(d,p) 17 O Proton spectrum at 45  and E d = 25.4 MeV (n-1d 5/2 ) 1 (n-2s 1/2 ) 1 (n-1d 3/2 ) 1

11 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen11 single-particle levels nl j shell gaps, intruder states level sequence in sd shell (n-1d 3/2 ) 1 (n-2s 1/2 ) 1 (n-1d 5/2 ) 1

12 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen12 stripping cross section for E d (v d )  binding of d and binding of n in A+1 nucleus A A+1 Fermi´s Golden Rule for weak d-A and p-(A-1) interaction: Born approx.: likely final state with n in outer shell: with shell-model w.f. for  n and short-range stripping interaction: q-transfer to nucleus!

13 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen13 DWBA for stripping reaction X(a,b)Y proton angular distribution for 16 O(d,p) 17 O at E d = 25.4 MeV plane waves  scattered waves: solutions for complex optical potential V(r) + iW(r) taking into account absorption by W(r) is Y=X+(a-b) a single-particle state ?? initial-state spin spectroscopic factors S l,j measure single-particle character l=0 l=2 q=0 excellent agreement for small q

14 HL-4 May 2004Kernfysica: quarks, nucleonen en kernen14 Summary lecture (HL-4) Nuclear structure Shell structure and shell gaps appear due to ls term Deformations in half-filled shells and polarization Nuclear reactions Stripping reactions study level structure DWBA approximation for transfer: spectroscopic factors S l,j measure single-particle character


Download ppt "HL-4 May 2004Kernfysica: quarks, nucleonen en kernen1 Outline lecture (HL-4) Structure of nuclei Shell structure Deformation Nuclear reactions Stripping."

Similar presentations


Ads by Google