Bulletin of the American Physical Society
APS April Meeting 2021
Volume 66, Number 5
Saturday–Tuesday, April 17–20, 2021; Virtual; Time Zone: Central Daylight Time, USA
Session L19: Searches for Axion Dark MatterLive
|
Hide Abstracts |
Sponsoring Units: DPF Chair: Daniel Bowring, Fermilab |
Sunday, April 18, 2021 3:45PM - 3:57PM Live |
L19.00001: Design and Instrumentation for ADMX-G2 Run 1C Nick Du The axion is a well-motivated particle that solves the Strong CP problem and is also a dark matter candidate. The Axion Dark Matter eXperiment (ADMX) searches for axion matter within the local Milky Way halo using an axion haloscope. In previous runs, ADMX was able to exclude the full range of axion to photon couplings predicted by benchmark models for the axion between 2.66-3.31 $\mu eV$. These limits mark ADMX as the only axion haloscope experiment to achieve sensitivity to the compelling DFSZ model for the axion. ADMX is currently searching for axions at higher masses with comparable sensitivity. In this talk, I will focus on the design and instrumentation used to achieve this sensitivity, which include a dilution refrigerator to achieve milli-Kelvin temperatures and an ultra-low noise Josephson Parametric Amplifier (JPA). I will also discuss the instrumentation need to higher frequency searches using a multi-cavity haloscope. [Preview Abstract] |
Sunday, April 18, 2021 3:57PM - 4:09PM Live |
L19.00002: Operational status for ADMX-G2 Run 1C Tatsumi Nitta The axion is a hypothetical particle that solves the strong CP problem and is a leading dark matter candidate. The Axion Dark Matter Experiment (ADMX) is an experiment that searches for axions as a dark matter. A strong magnetic field converts axions into photons, and a resonant cavity and low noise amplifiers represented by Josephson Parametric Amplifier (JPA) amplify photon signals. At the previous run periods, run 1A and run 1B achieved sensitivity to search for the full range of axion-photon couplings predicted by promising benchmark models and exclude axions around 2.66-3.31 micro-eV. This sensitivity relies on the system noise temperature calculated by the SNRI method for JPA and the Y-factor method for warmer electronics. The ongoing run period of run 1C is searching for axions at a higher mass range. This talk reports the detail of operational status and the latest results of the system noise temperature measurement. [Preview Abstract] |
Sunday, April 18, 2021 4:09PM - 4:21PM Live |
L19.00003: Searching for Potential Signals in the Noise for ADMX G2-Run 1C Chelsea Bartram The Axion Dark Matter eXperiment (ADMX) searches for axion dark matter candidates with a tunable haloscope consisting of a microwave cavity in an 8 T magnetic field. Having achieved sensitivity to DFSZ axions several years ago, ADMX continues to operate with its exquisitely sensitive receiver chain. Axion signals would manifest in the digitized power spectra as small narrowband excesses on the order of less than a yoctowatt. This implies the necessity of a strong signal-to-noise ratio, as well as a robust understanding of the system noise. We discuss the ADMX analysis process for the current data-taking operation (Run 1C), which spans a frequency range from about 760 to 1020 MHz (3.14 to 4.21 $\mu$eV). The characterization of the system noise is presented, in addition to new techniques to reject radio-frequency interference (RFI). The decision tree that is used to interrogate the nature of potential axion signals is presented. [Preview Abstract] |
Sunday, April 18, 2021 4:21PM - 4:33PM Live |
L19.00004: ADMX High Resolution Analysis A. T. Hipp The goal of the Axion Dark Matter Experiment (ADMX) is to detect axions in the galactic halo via their conversion to microwave photons within a cavity. The experiment currently has two analysis channels, one with a frequency resolution of 200Hz referred to as medium res and another with a frequency resolution of 20mHz referred to as HiRes. In the most recent run, run 1c, the data sent to the HiRes channel was in the form of a complex time series. We present our methods and results for the analysis of this data. First, we will discuss the analysis of synthetic axions and pure noise. Next, how this analysis informed our decisions on what qualifies as a possible axion signal and the application thereof to the entire 1c data. Lastly, we will comment on the future work, particularly multi-resolution searches. [Preview Abstract] |
Sunday, April 18, 2021 4:33PM - 4:45PM Live |
L19.00005: Future Plans for the Axion Dark Matter Experiment (ADMX) Gianpaolo Carosi Dark matter is likely to be made of new, as yet undiscovered particles and a very well motivated candidate is the axion, a light ($\mu$eV-meV) mass pseudoscalar neutral boson. It’s possible detection can be made using a large scale cryogenic microwave cavity placed in a high magnetic field. The Axion Dark Matter eXperiment (ADMX), a DOE Generation 2 dark matter project, is currently the only operating experiment sensitive to primordial axions with DFSZ scale couplings. ADMX is currently operating in the 0.6-2 GHz range as part of the G2 program but has begun to lay the groundwork to extend the range to higher frequencies. Here I will give an overview of the ADMX 2-4+ GHz system which aims to use multiple co-added microwave cavities to increase the scan rate for higher mass axions. This system will likely use a new, higher field magnet system than the current ADMX system and represents a large increase in complexity with 10s of cavities being coherently combined digitally. We will go through the current plans and anticipated reach of the next generation system. [Preview Abstract] |
Sunday, April 18, 2021 4:45PM - 4:57PM Live |
L19.00006: ADMX-Orpheus: A Dielectrically-Loaded Fabry-Perot Resonator to Search for Higher-Mass Axions Raphael Cervantes The ADMX experiment is currently searching for axions in the dark matter halo using a microwave cavity immersed in a strong magnetic field. The ADMX haloscope operates between 600 MHz and 1 GHz to search for axions with masses of a few micro-eV. However, this method is challenging to implement at higher masses because the cavity would need to have a smaller volume, reducing the signal strength. Thus, there is interest in developing more exotic resonators to address this issue. The ADMX-Orpheus haloscope is an open Fabry-Perot resonator with periodically placed dielectrics. This configuration allows for higher-order modes to couple with the axion while keeping the volume large. ADMX-Orpheus is designed to operate between 15 GHz and 18 GHz to search for axion-like particles around 70 micro-eV. I will discuss the development and characterization of the Orpheus resonator and the ongoing preparations to search for axion-like particles. [Preview Abstract] |
Sunday, April 18, 2021 4:57PM - 5:09PM Live |
L19.00007: The CASPEr-e Search for Axion-like Dark Matter Using Solid-state Nuclear Magnetic Resonance Deniz Aybas, J. Adam, E. Blumenthal, A. V. Gramolin, D. Johnson, A. Kleyheeg, S. Afach, J. W. Blanchard, G. P. Centers, A. Garcon, M. Engler, N. L. Figueroa, M. G. Sendra, A. Wickenbrock, M. Lawson, T. Wang, T. Wu, H. Luo, H. Mani, P. Mauskopf, P. W. Graham, S. Rajendran, D. F. Jackson Kimball, D. Budker, A. O. Sushkov We present the results of an experimental search for axion-like dark matter in the mass range 162 neV to 166 neV. The detection scheme of our Cosmic Axion Spin Precession Experiment (CASPEr) is based on a precision measurement of $^{207}$Pb nuclear magnetic resonance in a polarized ferroelectric crystal [D. Budker, et al., Phys. Rev. X 4, 021030] at 4.4 T field with a resonant circuit coupled to a low-noise amplifier. Our measurements place upper bounds on the electric-dipole moment coupling $|g_d|<7.0\times10^{-4}\mathrm{GeV}^{-2}$ and the gradient coupling $|g_{\mathrm{aNN}}|<2.1\times10^{-1}\mathrm{GeV}^{-1}$ of axion-like dark matter with 95\% confidence level in the searched mass range [D. Aybas, et al., arXiv:2101.01241]. [Preview Abstract] |
Sunday, April 18, 2021 5:09PM - 5:21PM On Demand |
L19.00008: Search for Halo Axions with Ferromagnetic Toroids (SHAFT Experiment) Alexander Gramolin, Deniz Aybas, Dorian Johnson, Janos Adam, Alexander Sushkov We present the results of the SHAFT experiment to search for axion-like dark matter in the mass range from 12 peV to 12 neV. The experiment is sensitive to the oscillating magnetic field that would be sourced by an axion-like dark matter halo of our Galaxy interacting with a strong static magnetic field in the lab. We employ toroidal ferromagnetic cores made of powdered iron-nickel alloy to enhance the static magnetic field by a factor of 24. Using superconducting quantum interference devices (SQUIDs), we achieve a magnetic sensitivity of $150~\mathrm{aT}/\sqrt{\mathrm{Hz}}$. This sensitivity allows us to improve, over a part of our mass range, the existing laboratory limits on the electromagnetic coupling of axion-like dark matter, reaching $4 \times 10^{-11}~\mathrm{GeV}^{-1}$ at 20 peV with 95\% confidence level. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700