Tesis doctoral de Lucia Soledad Caceres Monllor
Contents 1 introduction 7 2 motivation 11 2.1 the nuclear shell model . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.1.1 empirical shell model . . . . . . . . . . . . . . . . . . . . . . . 12 2.1.2 realistic shell model . . . . . . . . . . . . . . . . . . . . . . . . 13 2.2 electromagnetic transitions . . . . . . . . . . . . . . . . . . . . . . . . 13 2.2.1 the internal electron conversion . . . . . . . . . . . . . . . . . . 13 2.2.2 electromagnetic transition operators . . . . . . . . . . . . . . . 14 2.3 nuclear isomerism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2.4 nuclear structure near the doubly-magic 132sn . . . . . . . . . . . . . . 17 2.4.1 single particle energy levels in 132sn . . . . . . . . . . . . . . . . 17 2.4.2 ¯-decay spectroscopy studies . . . . . . . . . . . . . . . . . . . 20 2.4.3 r-process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 3 experimental techniques 29 3.1 production of exotic nuclei . . . . . . . . . . . . . . . . . . . . . . . . . 31 3.1.1 projectile fragmentation . . . . . . . . . . . . . . . . . . . . . . 31 3.1.2 in-ight ssion . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 3.2 the fragment separator (frs) at gsi . . . . . . . . . . . . . . . . . 33 3.2.1 b¿-¢e-b¿ method . . . . . . . . . . . . . . . . . . . . . . . . . 35 3.2.2 the frs particle identication detectors . . . . . . . . . . . . . 37 3.2.2.1 the multi wire proportional counter (mwpc) . . . . 37 3.2.2.2 the multi sampling ionization chamber (music) detector . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 3.2.2.3 the scintillators sci1, sci2 and sci3 . . . . . . . . . 39 3.3 monte-carlo simulations . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3.4 calibration of the frs . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 3.4.1 calibration of the mwpc detector . . . . . . . . . . . . . . . . 42 3.4.2 calibration of the music detector . . . . . . . . . . . . . . . . 43 3.4.3 calibration of the the time-of-ight detectors . . . . . . . . . . 45 3.5 particle identication . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 3.6 the rising °-array . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 3.6.1 the cluster detectors . . . . . . . . . . . . . . . . . . . . . . . . 49 3.6.2 °-ray add-back conditions . . . . . . . . . . . . . . . . . . . . 52 3.7 alternative experimental techniques . . . . . . . . . . . . . . . . . . . . 53 3 4 contents 4 particle identication analysis 55 4.1 isotope identication . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 5 analysis of the delayed °-ray spectra and results 61 5.1 the nucleus 130cd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 5.1.1 eect of the particle selection on the °-ray spectrum . . . . . . 66 5.1.1.1 contamination in the ° energy spectrum caused by reactions in the degrader at s4 . . . . . . . . . . . . . . 66 5.1.1.2 ion tracking detectors: the eect of the conditions on the mpwc detectors . . . . . . . . . . . . . . . . . . . 67 5.1.1.3 reactions in the music detectors . . . . . . . . . . . 67 5.2 the nucleus 128cd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 5.3 the nucleus 126cd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 5.4 the nucleus 131in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 6 discussion 99 6.1 n = 82 shell quenching . . . . . . . . . . . . . . . . . . . . . . . . . . 99 6.1.1 astrophysical implications . . . . . . . . . . . . . . . . . . . . . 103 6.2 empirical j2 two-body interaction . . . . . . . . . . . . . . . . . . . . . 103 6.3 proton-neutron interaction in neutron rich nuclei . . . . . . . . . . . . 104 7 summary 109 apendix a: additional coincidence energy spectra gated by the ° transitions observed in the 126cd isomeric decay 113 apendix b: time distributions of the ° lines observed in the 126cd isomeric decay 124 bibliography 128
Datos académicos de la tesis doctoral «Nuclear structure studies in the vicinity of the doubly-magic 132sn nucleus.«
- Título de la tesis: Nuclear structure studies in the vicinity of the doubly-magic 132sn nucleus.
- Autor: Lucia Soledad Caceres Monllor
- Universidad: Autónoma de Madrid
- Fecha de lectura de la tesis: 24/10/2008
Dirección y tribunal
- Director de la tesis
- Andrea Jungclaus
- Tribunal
- Presidente del tribunal: María jose Garcia borge
- alfredo Poves paredes (vocal)
- José Benlliure anaya (vocal)
- Andrés Gadea raga (vocal)