MIRACLS- the Multi Ion Reflection Apparatus for Collinear Laser Spectroscopy

by Stephan Malbrunot (CERN)

Wednesday 14 Nov 2018, 14:30 → 15:30 Europe/Zurich

Collinear laser spectroscopy (CLS) is a powerful tool to access nuclear ground state properties
such as spin, charge radius, and electromagnetic moments with high precision and accuracy [1].
Conventional CLS is based on the optical detection of fluorescence photons from laser-excited
ions or atoms. It is limited to radioactive ion beams (RIB) with yields of more than 100 to 10,000
ions/s, depending on the specific case and spectroscopic transition. Consequently, the study of the
most exotic nuclides synthesised at today’s RIB facilities demands for more sensitive experimental
methods.
Complementary to Collinear Resonance Ionization Spectroscopy (CRIS) [2] or more specialised
techniques, e.g. [3], we are currently developing the Multi Ion Reflection Apparatus for Collinear
Laser Spectroscopy (MIRACLS) at ISOLDE/CERN. Supported by an ERC Starting Grant, this
novel approach is determined to enhance the sensitivity of CLS by a factor of 20-600. It is based
on a Multi-Reflection Time-of-Fight (MR-ToF) device in which the ions bounce back and forth
between two electrostatic mirrors [4]. When operating a MR-ToF apparatus with an unprecedented
ion-beam energy of 30 keV, this scheme allows extended observation times and hence higher
experimental sensitivity while preserving the high resolution of conventional CLS.
Recently, the first MIRACLS signals were obtained in a proof-of-principle experiment in a low
energy MR-ToF apparatus [5] which has been modified for the purpose of CLS to experimentally
demonstrate the potential of the MIRACLS approach.
This talk will introduce the MIRACLS concept and will present the current status of the project.

 

[1] K. Blaum, et al., Phys. Scr. T152, 014017 (2013)
P. Campbell et al., Prog. Part. and Nucl. Phys. 86, 127-180 (2016)
R. Neugart et al., J. Phys. G: Nucl. Part. Phys. 44, 064002 (2017)
[2] K. T. Flanagan. Nuclear Physics News 23, 2 24 (2013),
T. E. Cocolios et al., Nucl. Instrum. Methods Phys. Res. B 317, 565 (2013)
[3] R. F. Garcia Ruiz et al., J. Phys. G: Nucl. Part. Phys. 44, 044003 (2017)
[4] H. Wollnik and M. Przewloka, Int. J. Mass Spectrom. 96, 267 (1990)
D. Zajfman et al, Phys. Rev. A 55, 1577 (1997)
W.H. Benner, Anal. Chem. 69, 4162 (1997)
W.R. Plass et al., Nucl. Instrum. Meth. B 266 4560 (2008)
A. Piechaczek et al., Nucl. Instr. Meth. B 266, 4510 (2008)
P. Schury et al., Eur. Phys. J. A 42, 343–349 (2009)
J.D. Alexander et al., J. Phys. B 42, 154027 (2009)
M. Lange et al., Rev. Sci. Instrum. 81, 055105 (2010)
R. N. Wolf et al., Int. J. Mass Spectrom. 349-350, 123-133 (2013)
F. Wienholtz et al., Nature 498, 346-349 (2013)
[5] M. Rosenbusch et al. AIP Conf. Proc., 1521:53, (2013), AIP Conf. Proc., 1668:050001, (2015).