2019 CAP Congress / Congrès de l'ACP 2019

3 - Upgrade of the electrostatic spectrometer and ion/shakeoff detectors in TRIUMF's neutral atom trap apparatus.

4 Jun 2019, 16:49

2m

SWH 9082 + AQ South-East Corner / coin sud-est (Simon Fraser University)

Poster (Non-Student) / Affiche (Non-étudiant(e)) Applied Physics and Instrumentation / Physique appliquée et de l'instrumentation (DAPI / DPAI) DAPI Poster Session & Student Poster Competition Finals (8) | Session d'affiches DPIA et finales du concours d'affiches étudiantes (8)

Speaker

Alexandre Gorelov (TRIUMF)

Description

Measurements of correlation parameters from beta decay of atoms in a MOT may
require application of an electric field, which can work as a spectrometer for
recoiling ions and atomic shake-off electrons on their way to MCP based
detectors in a back-to-back geometry. Such a field, in combination with the
drift distance, separates in time the arrival of recoiling, differently charged
ionized atoms on an ion detector relative to much faster moving shake-off
electrons, detected by an electron MCP. This allows us to distinguish between
ions with different charge and calculate correct kinematics event by event.

In our earlier measurements of the beta asymmetry from beta decay of trapped
polarized ${}^{37}K$ atoms [B.Fenker et al. Phys. Rev. Lett. 120 062502 (2018)],
we have achieved an electric field of about 540V/cm. Further increase of the
field prevented simultaneous detection of ion and electrons, resulting in high,
up to 1MHz, background count rate in both detectors. Recent development of
spectrometer allowed us to reach a field strength of 1000V/cm and ensure
reliable simultaneous operation of both ion and electron MCP based detectors
in beta decay measurements of trapped ${}^{92}Rb$ [J.McNeil, contributed talk to
DNP-DPN].

Presentation materials

gorelov_cap2019_poster.pdf