Engineering topics

Majorovits, B.

Publications and source records attributed to Majorovits, B..

5 records

DOE OSTI2025

First Search for Dark Photon Dark Matter with a madmax Prototype

We report the first result from a dark photon dark matter search in the mass range from 78.62 to 83.95 μ eV / c 2 with a dielectric haloscope prototype for (Magnetized Disc and Mirror Axion eXperiment). Putative dark photons would convert to detectable photons within a stack consisting of three sapphire disks and a mirror. The emitted power of this system is received by an antenna and successively digitized using a low-noise receiver. No significant signal attributable to dark photons has been observed above the expected background. Assuming unpolarized dark photon dark matter with a local density of ρ χ = 0.3 G eV cm 3 we exclude a dark photon to photon mixing parameter χ > 2.7 × 10 − 12 over the full mass range and χ > 1.1 × 10 − 13 at a mass of 80.57 μ eV / c 2 with a 95% confidence level. This is the first physics result from a prototype and exceeds previous constraints on χ in this mass range by up to almost three orders of magnitude. Published by the American Physical Society 2025

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2022

Erratum: Production and validation of scintillating structural components from low-background Poly(ethylene naphthalate)

Regretfully, the author list of the original paper did not contain the members of the groups being responsible for the HPGe screening, Radon emanation measurement and ICPMS surface characterization works. As the work performed is to be considered more than “just service work”, the authors together with the members of these groups have decided to amend the authors list. At publication the following authors were not included in the author list: • From Pacific Northwest National Laboratory, Richland, WA, U.S.A.: E.W. Hoppe, I.J. Arnquist, K.P. Hobbs, A.D. French, M.L. diVacri • From INFN, Laboratori Nazionali del Gran Sasso, 67100 Assergi, Italy: M. Laubenstein • From M. Smoluchowski Institute of Physics, Jagiellonian University, 30-348 Krakow, Poland: G. Zuzel The metadata of the present erratum are already correct.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2022

Axion Dark Matter

Axions are well-motivated dark matter candidates with simple cosmological production mechanisms. They were originally introduced to solve the strong CP problem, but also arise in a wide range of extensions to the Standard Model. This Snowmass white paper summarizes axion phenomenology and outlines next-generation laboratory experiments proposed to detect axion dark matter. There are vibrant synergies with astrophysical searches and advances in instrumentation including quantum-enabled readout, high-Q resonators and cavities and large high-field magnets. This white paper outlines a clear roadmap to discovery, and shows that the US is well-positioned to be at the forefront of the search for axion dark matter in the coming decade.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2022

Production and validation of scintillating structural components from low-background Poly(ethylene naphthalate)

Poly Ethylene Naphthalate (PEN) is an industrial polymer plastic which is investigated as a low background, transparent, scintillating and wavelength shifting structural material. PEN scintillates in the blue region and has excellent mechanical properties both at room and cryogenic temperatures. Thus, it is an ideal candidate for active structural components in experiments for the search of rare events like neutrinoless double-beta decay or dark matter recoils. Such optically active structures improve the identification and rejection efficiency of backgrounds events, like this improving the sensitivity of experiments. This paper reports on the production of radiopure and transparent PEN plates These structures can be used to mount germanium detectors operating in cryogenic liquids (LAr, LN). Thus, as first application PEN holders will be used to mount the Ge detectors in the LEGEND-200 experiment. The whole process from cleaning the raw material to testing the PEN active components under final operational conditions is reported.

47 OTHER INSTRUMENTATION↗

DOE OSTI2021

Simulating MADMAX in 3D: Requirements for Dielectric Axion Haloscopes

We present 3D calculations for dielectric haloscopes such as the currently envisioned MADMAX experiment. For ideal systems with perfectly flat, parallel and isotropic dielectric disks of finite diameter, we find that a geometrical form factor reduces the emitted power by up to 30% compared to earlier 1D calculations. We derive the emitted beam shape, which is important for antenna design. We show that realistic dark matter axion velocities of 10 -3 c and inhomogeneities of the external magnetic field at the scale of 10% have negligible impact on the sensitivity of MADMAX. We investigate design requirements for which the emitted power changes by less than 20% for a benchmark boost factor with a bandwidth of 50 MHz at 22 GHz, corresponding to an axion mass of 90 μeV. We find that the maximum allowed disk tilt is 100 μm divided by the disk diameter, the required disk planarity is 20 μm (min-to-max) or better, and the maximum allowed surface roughness is 100 μm (min-to-max). We show how using tiled dielectric disks glued together from multiple smaller patches can affect the beam shape and antenna coupling.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗