The Thf+ Eedm Experiment: Concept, Design, and Characterization

The Standard Model of particle physics is one of the most successful models that we have to describe the universe at a fundamental level. However, the Standard Model is known to be incomplete. For instance, the Standard Model does not explain the degree of abundance of matter over anti-matter. When theorists make extensions to the Standard Model through new physics models, their models usually make predictions on the value of the electric dipole moment of the electron (eEDM). By measuring (or placing improved limits on) the eEDM, we can place constraints on these new theories. The eEDM experiments at JILA use molecular ions to measure the eEDM. Molecular ions are good for two main reasons: (i) our molecules give us enhanced sensitivity to the eEDM, and (ii) trapped ions allow us to take advantage of the long coherence times of the eEDM-sensitive states. The Generation II JILA eEDM experiment using HfF+ concluded in November 2022 by setting the world&rsquo;s best limit. In our Generation III project, we seek to further improve upon our limit by switching over to ThF+, which promises enhanced sensitivity to the eEDM. Herein, I present (i) spectroscopy work performed on ThF+ to allow us to control the molecule in both the external and internal degrees of freedom, (ii) design and characterization of a prototype of a multiplexed ion trap.</p

Visible and Ultraviolet Laser Spectroscopy of ThF

The molecular ion ThF$^+$ is the species to be used in the next generation of search for the electron's Electric Dipole Moment (eEDM) at JILA. The measurement requires creating molecular ions in the eEDM sensitive state, the rovibronic ground state $^3\Delta_1$, $v^+=0$, $J^+=1$. Survey spectroscopy of neutral ThF is required to identify an appropriate intermediate state for a Resonance Enhanced Multi-Photon Ionization (REMPI) scheme that will create ions in the required state. We perform broadband survey spectroscopy (from 13000 to 44000~cm$^{-1}$) of ThF using both Laser Induced Fluorescence (LIF) and $1+1'$ REMPI spectroscopy. We observe and assign 345 previously unreported vibronic bands of ThF. We demonstrate 30\% efficiency in the production of ThF$^+$ ions in the eEDM sensitive state using the $\Omega = 3/2$ [32.85] intermediate state. In addition, we propose a method to increase the aforementioned efficiency to $\sim$100\% by using vibrational autoionization via core-nonpenetrating Rydberg states, and discuss theoretical and experimental challenges. Finally, we also report 83 vibronic bands of an impurity species, ThO.Comment: 49 pages, 7 figure

Systematic and statistical uncertainty evaluation of the HfF+^+ electron electric dipole moment experiment

We have completed a new precision measurement of the electron's electric dipole moment using trapped HfF$^+$ in rotating bias fields. We report on the accuracy evaluation of this measurement, describing the mechanisms behind our systematic shifts. Our systematic uncertainty is reduced by a factor of 30 compared to the first generation of this measurement. Our combined statistical and systematic accuracy is improved by a factor of 2 relative to any previous measurement

A new bound on the electron's electric dipole moment

The Standard Model cannot explain the dominance of matter over anti-matter in our universe. This imbalance indicates undiscovered physics that violates combined CP symmetry. Many extensions to the Standard Model seek to explain the imbalance by predicting the existence of new particles. Vacuum fluctuations of the fields associated with these new particles can interact with known particles and make small modifications to their properties; for example, particles which violate CP symmetry will induce an electric dipole moment of the electron (eEDM). The size of the induced eEDM is dependent on the masses of the new particles and their coupling to the Standard Model. To date, no eEDM has been detected, but increasingly precise measurements probe new physics with higher masses and weaker couplings. Here we present the most precise measurement yet of the eEDM using electrons confined inside molecular ions, subjected to a huge intra-molecular electric field, and evolving coherently for up to 3 s. Our result is consistent with zero and improves on the previous best upper bound by a factor $\sim2.4$. Our sensitivity to $10^{-19}$ eV shifts in molecular ions provides constraints on broad classes of new physics above $10^{13}$ eV, well beyond the direct reach of the LHC or any other near- or medium-term particle collider.Comment: Update to figure 2 which displays better in some pdf viewer

Experimental Constraint on Axionlike Particles over Seven Orders of Magnitude in Mass

We use our recent electric dipole moment (EDM) measurement data to constrain the possibility that the HfF+ EDM oscillates in time due to interactions with candidate dark matter axionlike particles (ALPs). We employ a Bayesian analysis method which accounts for both the look-elsewhere effect and the uncertainties associated with stochastic density fluctuations in the ALP field. We find no evidence of an oscillating EDM over a range spanning from 27 nHz to 400 mHz, and we use this result to constrain the ALP-gluon coupling over the mass range 10-22-10-15 eV. This is the first laboratory constraint on the ALP-gluon coupling in the 10-17-10-15 eV range, and the first laboratory constraint to properly account for the stochastic nature of the ALP field

LIF SPECTROSCOPY OF ThF AND THE PREPARATION OF ThF+ FOR THE JILA eEDM EXPERIMENT

ThF$^{+}$ is a promising candidate for a second-generation molecular ion-based measurement of the permanent electric dipole moment of the electron (eEDM). Compared to the current HfF$^{+}$ eEDM experiment, ThF$^{+}$ has several advantages: (i) the eEDM-sensitive $^{3}Delta_1$ electronic state is the ground state, which facilitates a long measurement coherence time; (ii) its effective electric field (38 GV/cm) is 50% larger than that of HfF+, which promises a direct increase of the eEDM sensitivity; and (iii) the ionization energy of neutral ThF is lower than its dissociation energy, which introduces a greater flexibility for rotational state-selective photoionization via core-nonpenetrating Rydberg states. We use laser-induced fluorescence (LIF) spectroscopy to find suitable intermediate states required for the state selective ionization process. We present the results of our LIF spectroscopy of ThF, and our current progress on efficient ThF ionization and on ThF$^{+}$ dissociation

A TRIZ-Inspired Conceptual Development of a Roof Tile Transportation and Inspection System

The Indonesian roof tile manufacturing industry relies heavily on manual operations, specifically in transportation and inspection processes, which creates multiple issues, such as fatigue, injuries, human error, and reduced productivity. Various industries in the Indonesian industrial landscape have begun embracing a problem-solving approach known as the theory of inventive problem-solving (TRIZ) to mine solutions for industrial issues. Nevertheless, its application in the Indonesian roof tile manufacturing industry remains unaddressed. The study aims to solve manual handling issues in the roof tile manufacturing industry using TRIZ. Three observations were outlined from manual roof tile transportation and inspection, followed by the formulation of engineering contradictions (ECs). The ECs were linked with system parameters, which were used as indicators within the contradiction matrix to extract inventive principles as solution models for conceptual development. The concept included an automated system with a conveyor belt (#15: dynamics) for effective transportation, automated image capture (#28: mechanics substitution) for effective inspection, and a flipping conveyor (#25: self-service) to eliminate manual contact. Although the study addressed several issues stemming from manual operations, mechanical analysis, prototyping, and usability testing still require improvements

A TRIZ-Supported Concept and Protocol Development for Roof Tile Transportation and Inspection Systems

Currently, the use of manual labour in the transportation and inspection systems of leading roof tile manufacturing companies in Indonesia is still prevalent. Manual labour is usually labour-intensive, has higher risks of musculoskeletal disorders, and produces frequent occurrences of errors and losses. Furthermore, the current studies of suitable concepts and test protocols for roof tile transportation at the manufacturing stage as well as their inspection systems are not practicable in Indonesia. There is also no study that has used the theory of inventive problem-solving (TRIZ) in the development of concepts and protocols for roof tile transportation and inspection systems. Using TRIZ as a supporting tool, this study investigated the development of a transportation system to be employed during the manufacturing of the roof tile and a test protocol for their usability in Indonesian companies to overcome this concern. The study included screening and scoring concepts and usability test protocols identified from the existing literature, with the support of TRIZ tools such as the engineering contradiction, contradiction matrix, and inventive principles. Thus, the finalised concept comprised a belt conveyor system (Inventive Principle 20: Continuity of Useful Action) with a flipping mechanism for transportation and a vision-based camera for inspection. Results of the study showed that the concept excelled in cost, durability, reliability, versatility, low risk to the product, efficiency, and safety. The t-test protocol (Inventive Principle 23: Feedback) was selected based on the results due to its versatility in testing efficiency, reliability, and productivity. It was concluded that this concept has the potential to alleviate roof tile workers of physical work and reduce the prevalence of musculoskeletal disorders

A TRIZ-Supported Concept and Protocol Development for Roof Tile Transportation and Inspection Systems

Currently, the use of manual labour in the transportation and inspection systems of leading roof tile manufacturing companies in Indonesia is still prevalent. Manual labour is usually labour-intensive, has higher risks of musculoskeletal disorders, and produces frequent occurrences of errors and losses. Furthermore, the current studies of suitable concepts and test protocols for roof tile transportation at the manufacturing stage as well as their inspection systems are not practicable in Indonesia. There is also no study that has used the theory of inventive problem-solving (TRIZ) in the development of concepts and protocols for roof tile transportation and inspection systems. Using TRIZ as a supporting tool, this study investigated the development of a transportation system to be employed during the manufacturing of the roof tile and a test protocol for their usability in Indonesian companies to overcome this concern. The study included screening and scoring concepts and usability test protocols identified from the existing literature, with the support of TRIZ tools such as the engineering contradiction, contradiction matrix, and inventive principles. Thus, the finalised concept comprised a belt conveyor system (Inventive Principle 20: Continuity of Useful Action) with a flipping mechanism for transportation and a vision-based camera for inspection. Results of the study showed that the concept excelled in cost, durability, reliability, versatility, low risk to the product, efficiency, and safety. The t-test protocol (Inventive Principle 23: Feedback) was selected based on the results due to its versatility in testing efficiency, reliability, and productivity. It was concluded that this concept has the potential to alleviate roof tile workers of physical work and reduce the prevalence of musculoskeletal disorders