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Béla Majorovits

Publications and source records attributed to Béla Majorovits.

5 recordsLinked to original sources

Comment on the preprint: First Limits on Axion Dark Matter from a DALI Prototype arXiv:2603.21951

We report on an independent assessment of the sensitivity of the DALI setup to axion-like particle (ALP) dark matter, as described in [1]. Our analysys is based on the information provided in the preprint and using the formalism developed within the MADMAX collaboration. We do not identify any mode below 12 GHz with significant coupling to the axion field to account for the reported sensitivity. We provide recommendations for assessing the axion coupling of electromagnetic modes in dielectric haloscope experiments.

hep-ex↗

Direct Detection of Dark Matter -- APPEC Committee Report

This Report provides an extensive review of the experimental programme of direct detection searches of particle dark matter. It focuses mostly on European efforts, both current and planned, but does it within a broader context of a worldwide activity in the field. It aims at identifying the virtues, opportunities and challenges associated with the different experimental approaches and search techniques. It presents scientific and technological synergies, both existing and emerging, with some other areas of particle physics, notably collider and neutrino programmes, and beyond. It addresses the issue of infrastructure in light of the growing needs and challenges of the different experimental searches. Finally, the Report makes a number of recommendations from the perspective of a long-term future of the field. They are introduced, along with some justification, in the opening Overview and Recommendations section and are next summarised at the end of the Report. Overall, we recommend that the direct search for dark matter particle interactions with a detector target should be given top priority in astroparticle physics, and in all particle physics, and beyond, as a positive measurement will provide the most unambiguous confirmation of the particle nature of dark matter in the Universe.

hep-ex↗

A first proof of principle booster setup for the MADMAX dielectric haloscope

Axions and axion-like particles are excellent low-mass dark matter candidates. The MADMAX experiment aims to directly detect galactic axions with masses between $40\,μ{\rm eV}$ and $400\,μ{\rm eV}$ by using the axion-induced emission of electromagnetic waves from boundaries between materials of different dielectric constants under a strong magnetic field. Combining many such surfaces, this emission can be significantly enhanced (boosted) using constructive interference and resonances. We present a first proof of principle realization of such a booster system consisting of a copper mirror and up to five sapphire disks. The electromagnetic response of the system is investigated by reflectivity measurements. The mechanical accuracy, calibration process of unwanted reflections and the repeatability of a basic tuning algorithm to place the disks are investigated. We find that for the presented cases the electromagnetic response in terms of the group delay predicted by one-dimensional calculations is sufficiently realized in our setup. The repeatability of the tuning is at the percent level, and would have small impact on the sensitivity of such a booster.

physics.ins-det↗

MADMAX: A new Dark Matter Axion Search using a Dielectric Haloscope

The axion is an intriguing dark matter candidate emerging from the Peccei-Quinn solution to the strong CP problem. Current experimental searches for axion dark matter focus on the axion mass range below 40 $μ$eV. However, if the Peccei-Quinn symmetry is restored after inflation the observed dark matter density points to an axion mass around 100 $μ$eV. A new project based on axion-photon conversion at the transition between different dielectric media is presented. By using $\sim 80$ dielectric discs, the emitted power could be enhanced by a factor of $\sim 10^5$ over that from a single mirror (flat dish antenna). Within a 10 T magnetic field, this could be enough to detect $\sim 100 μ$eV axions with HEMT linear amplifiers. The design for an experiment is proposed. Results from noise, transmissivity and reflectivity measurements obtained in a prototype setup are presented. The expected sensitivity is shown.

astro-ph.IM↗

Development of an anti-Compton veto for HPGe detectors operated in liquid argon using Silicon Photo-Multipliers

A proof of concept detector is presented for scintillation light detection in liquid argon using Silicon Photo-Multipliers. The aim of the work is to build an anti-Compton veto for germanium detectors operated directly in liquid argon like in the GERDA experiment. Properties of the Multi-Pixel Photon Counter (MPPC) are studied at cryogenic temperatures. To increase the light collection efficiency of the MPPCs wavelength shifting fibers were used. A veto efficiency comparable to a similar setup with a Photo-Multiplier Tube was achieved.

physics.ins-det↗