Report

Teaser, summary, work performed and final results

Periodic Reporting for period 2 - TRAPLAB (Lab Based Searches for Beyond Standard Model Physics Using Traps)

Teaser

It is quite clear that the standard model of particle physics is incomplete, as it fails to describe some of the phenomena observed in nature (for example, is does not account for dark matter, or dark energy). Searches for new physics proceed mostly in high energy accelerators...

Summary

It is quite clear that the standard model of particle physics is incomplete, as it fails to describe some of the phenomena observed in nature (for example, is does not account for dark matter, or dark energy). Searches for new physics proceed mostly in high energy accelerators attempting to access the energy scale of the new physics.
This project takers a different route to the attempt at detection of new physics, by performing high precision measurement at low energies in the lab, and comparing the results to calculations done using the standard model, one can detect deviations from the calculations and relate them to new physics.
Specifically, we aim to trap radioactive ions and atoms produced in an accelerator and study their decay properties, since these properties, and in particular, angular correlation between the different ejecta, may be calculated to high precision within the standard model, and may also be accurately measured in the trap setup, a comparison of theory to experiment in a highly sensitive probe for new physics.

Work performed

We have developed two high efficiency trap, one for neon isotopes, based on a combinations of lasers and magnetic fields (a Magneto-Optical Trap, MOT), and an ion trap which trap a moving bunch of ions and may be applied to any atom species (an Electrostatic Ion Beam Trap, EIBT). These two trap were installed in a newly constructed isotope production complex (constructed specifically for this project) at the Soreq Nuclear Research Center’s new accelerator facility. This lab complex now represents the only such facility in the world where two completely different experimental setups are probing the same decay physics, which will provide for a crucial cross check of the final results. Additionally, the EIBT is the only such setup of its king in the world dedicated to radioactive decay studies.

We have demonstrated trapping of stable species (neon in the MOT and helium in the EIBT) and have used the MOT to perform a series of ground breaking experiments in cold chemistry on neon atoms, which have proven that our system is able to reach the required precision for the final experiment using radioactive neon atoms.

We have also developed and demonstrated a production scheme for our first two isotopes of interest, 23Ne and 6He, using the Soreq Applied Research Accelerator Facility, and have proven that the required isotopes may be produced at the required quantity for our experiment to provide high precision results. As part of this proof of concept, we have taken experimental data on 23Ne which will allow us to extract the world’s best determination of the decay branching ratios, a crucial component of the theory calculation.

On the theory side, we have suggested and published a novel scheme to test for Beyond Standard Model physics in a particular type of radioactive decay terms “unique first forbidden decays”. We are now developing this idea into an experimental proposal. Additionally, we have made significant progress in the calculation on the so called “recoil-order corrections”, which are required for the full analysis of the experiments, the new calculations will, when completed, represent the world’s best such calculations, and will allow us to push the limit of our precision further.

Final results

By the end of the project we expect to trap radioactive isotopes in both experimental systems and measure their decay properties, allowing us to analyze the data and set bounds of the existence of beyond standard model physics in some regions of the parameter space. For the neon isotopes we expect an improvement of at least a factor of 5 in the current best limits, and for 6He we expect an improvement of at least a factor 2.

Website & more info

More info: http://www.phys.huji.ac.il/.