Spectroscopy of Superheavy Nuclei: The SAGE spectrometer
Lead Research Organisation:
University of Liverpool
Department Name: Physics
Abstract
The majority of the mass of the universe is made up of atomic nuclei that lie at the centre of the atom. Nuclei contain positively charged protons and electrically neutral neutrons. The lightest known nucleus is that of hydrogen that contains just one proton but no one yet knows how heavy a nucleus can be; in other words, just how many neutrons and protons can be made to bind together. The aim of this proposal is to address this question by studying the heaviest nuclei that can be made in the laboratory. These nuclei are extremely difficult to create and study. The heaviest man-made elements today (unnamed as yet) have as many as 116 protons, but have been produced in tiny quantities of a few atoms only. Both protons and neutrons are held together by the strong nuclear force but protons are repelled from each other because of their electric charge. The nuclear force has an extremely short range, affecting nearest neighbours only, so that, as more and more protons are added to a nucleus the electrostatic repulsion will eventually become stronger than the nuclear binding forces and the nucleus will become unstable. The neutrons and protons will no longer stick together. This should happen for nuclei beyond uranium, which has 92 protons but the existence of heavier species comes about because of the internal structure within the nuclei. Just as noble gases owe their inert chemical behaviour to a specific arrangement of electrons that has extra stability, so certain 'magic' proton and neutron numbers also enhance nuclear stability. This project is concerned with a detailed study of the underlying mechanisms that yield this extra stability and allow 'superheavy' nuclei to exist. The main focus of this work will be on nuclei around nobelium with 102 protons, approximately halfway between the well-studied nuclei around uranium and the frontier of superheavy elements. Here spectroscopic methods can be used to gain detailed insights into the shape of the nucleus and the b
Publications
Chatillon A
(2006)
Spectroscopy and single-particle structure of the odd- Z heavy elements 255Lr, 251Md and 247Es
in The European Physical Journal A
Cox D
(2015)
Simulation of the SAGE spectrometer
in The European Physical Journal A
Andreyev AN
(2013)
Signatures of the Z = 82 shell closure in a-decay process.
in Physical review letters
Greenlees PT
(2012)
Shell-structure and pairing interaction in superheavy nuclei: rotational properties of the z=104 nucleus (256)rf.
in Physical review letters
Bree N
(2014)
Shape coexistence in the neutron-deficient even-even (182-188)Hg isotopes studied via coulomb excitation.
in Physical review letters
Gaffney L
(2014)
Shape coexistence in neutron-deficient Hg isotopes studied via lifetime measurements in Hg 184 , 186 and two-state mixing calculations
in Physical Review C
Robinson A
(2011)
Search for a 2-quasiparticle high- K isomer in Rf 256
in Physical Review C
Leppänen A
(2006)
Recoil-fission tagging of the transfermium nucleus 252No
in The European Physical Journal A
Li H
(2015)
Recoil-decay tagging spectroscopy of 74 162 W 88
in Physical Review C
Peura P
(2014)
Quasiparticle alignments and a -decay fine structure of 175 Pt
in Physical Review C
Description | GREAT collaboration |
Organisation | University of Jyvaskyla |
Department | Department of Physics |
Country | Finland |
Sector | Academic/University |
PI Contribution | Constructed GREAT spectrometer and TDR DAQ system. Spokesperson of many experiments. |
Collaborator Contribution | facility |
Impact | 24 outputs |
Description | TASCA Collaboration |
Organisation | Gesellschaft für Schwerionenforschung |
Department | Nuclear Physics (Superheavy Elements) |
Country | Germany |
Sector | Academic/University |
PI Contribution | Parts of the detection system, Manpower, Data Analysis, Monte Carlo Simulation, Intellectual Input |
Collaborator Contribution | Technical Support for Experiment |
Impact | Confirmation of Element 114 and New isotope 277Hs (Duellmann et al, PRL 104 2010 252701) Spectroscopy of 253No (Anderson et al, NIMA622 2010 164) |
Start Year | 2006 |
Description | TASCA Collaboration |
Organisation | Helmholtz Association of German Research Centres |
Department | Helmholtz Institute Mainz |
Country | Germany |
Sector | Academic/University |
PI Contribution | Parts of the detection system, Manpower, Data Analysis, Monte Carlo Simulation, Intellectual Input |
Collaborator Contribution | Technical Support for Experiment |
Impact | Confirmation of Element 114 and New isotope 277Hs (Duellmann et al, PRL 104 2010 252701) Spectroscopy of 253No (Anderson et al, NIMA622 2010 164) |
Start Year | 2006 |
Description | TASCA Collaboration |
Organisation | Johannes Gutenberg University of Mainz |
Country | Germany |
Sector | Academic/University |
PI Contribution | Parts of the detection system, Manpower, Data Analysis, Monte Carlo Simulation, Intellectual Input |
Collaborator Contribution | Technical Support for Experiment |
Impact | Confirmation of Element 114 and New isotope 277Hs (Duellmann et al, PRL 104 2010 252701) Spectroscopy of 253No (Anderson et al, NIMA622 2010 164) |
Start Year | 2006 |