Speaker
Pilippos Papadakis
(University of Jyvaskyla (FI))
Description
The SPEDE spectrometer [1, 2] aims to combine a silicon detector, for the detection of electrons, with the MINIBALL $\gamma$-ray detection array for in-beam studies employing radioactive ion beams at the HIE-ISOLDE facility at CERN. SPEDE is one of the first attempts to combine in-beam $\gamma$-ray and conversion electron spectroscopy with radioactive ion beams.
The setup will be primarily used for octupole collectivity [3] and shape coexistence studies [4, 5] in Coulomb excitation experiments. In the shape coexistence cases the transitions between states of the same spin and parity have enhanced E0 strength [6]. Additionally the 0$^+$→0$^+$ transitions, typically present in nuclei exhibiting shape coexistence [7], can only occur via E0 transitions, i.e. via internal conversion electron emission. The simultaneous observation of both electrons and $\gamma$-rays is especially important for the analysis of multi-step Coulex data.
The concept of the SPEDE spectrometer was introduced for the ISOLDE community in the previous users meeting. In this presentation the finalized design of the spectrometer will be described together with results from the first tests.
[1] J. Pakarinen et al., Letter of Intent to the INTC for HIE-ISOLDE (2010).
[2] J. Konki et al., EPJ Web of Conferences 63, 01019 (2013).
[3] P.A Butler et al., Proposal to the INTC for HIE-ISOLDE (2012).
[4] K. Wrzosek-Lipska et al., Proposal to the INTC for HIE-ISOLDE (2012).
[5] J. Pakarinen et al., Proposal to the INTC for HIE-ISOLDE (2013).
[6] C.Y. Wu et al., Phys. Lett. B 541, 59 (2002).
[7] K. Heyde and J.L. Wood, Rev. Mod. Phys. 83, 1467 (2011).
Author
Pilippos Papadakis
(University of Jyvaskyla (FI))
Co-authors
Dr
Daniel Cox
(University of Liverpool)
Dr
David Jenkins
(University of York)
Mr
David Wells
(University of Liverpool)
George Genghis O'Neill
(University of Liverpool (GB))
Janne Pakarinen
(University of Jyvaskyla (FI))
Mr
Jim Thornhill
(University of Liverpool)
Joonas Konki
(University of Jyväskylä)
Mr
Kimmo Ranttila
(University of Jyväskylä)
Mark L Huyse
(KU Leuven (BE))
Dr
Panu Rahkila
(University of Jyväskylä)
Dr
Paul Davies
(University of York)
Paul Thomas Greenlees
(University of Jyväskylä)
Prof.
Peter Butler
(University of Liverpool (GB))
Prof.
Piet Van Duppen
(KU Leuven (BE))
Rolf-Dietmar Herzberg
(U)
Mr
Ville-Pekka Saarela
(University of Jyväskylä)
