High-resolution for IAXO: MMC-based X-ray Detectors

Abstract

Axion helioscopes like the planned International Axion Observatory (IAXO) search for evidence of axions and axion-like particles (ALPs) from the Sun. A strong magnetic field is used to convert ALPs into photons via the generic ALP-photon coupling. To observe the resulting photons, X-ray detectors with low background and high efficiency are necessary. In addition, good energy resolution and low energy threshold would allow for investigating the ALP properties by studying the X-ray spectrum after its discovery. We propose to use low temperature metallic magnetic calorimeters (MMCs). Here we present the first detector system based on MMCs developed for IAXO and discuss the results of the characterization. The detector consists of a two-dimensional 64-pixel array covering an active area of 16 mm${}^2$ with a fill factor of 93 %. We achieve an average energy resolution of 6.1 eV FWHM allowing for energy thresholds below 100 eV. This detector is the first step towards a larger 1 cm${}^2$ array matching the IAXO X-ray optics. We determine the background rate for an unshielded detector system in the energy range between 1 keV and 10 keV to be $3.2(1)\times 10^{-4}$ keV${}^{-1}$ cm${}^{-2}$ s${}^{-1}$ from events acquired over 30 days. In the future, active and passive shields will significantly reduce the background induced by cosmic muons and natural radioactivity. Our results demonstrate that MMCs are a promising technology for helioscopes to discover and study ALPs.

References in corpus (21)

• The Low-Energy Frontier of Particle Physics
• New CAST Limit on the Axion-Photon Interaction
• WISPy Cold Dark Matter
• A Search for Invisible Axion Dark Matter with the Axion Dark Matter Experiment
• Any Light Particle Search II -- Technical Design Report
• Conceptual Design of the International Axion Observatory (IAXO)
• Evidence for a new light spin-zero boson from cosmological gamma-ray propagation?
• Physics potential of the International Axion Observatory (IAXO)
• Axions and the cooling of white dwarf stars
• Stellar Recipes for Axion Hunters
• Solar axion flux from the axion-electron coupling
• Measurement of the ${}^{229}$Th isomer energy with a magnetic micro-calorimeter
• Signatures of axion-like particles in the spectra of TeV gamma-ray sources
• CUORE-0 detector: design, construction and operation
• Axion helioscopes as solar magnetometers
• Weighing the Solar Axion
• Distinguishing Axion Models with IAXO
• Axions as a probe of solar metals
• The Tokyo Axion Helioscope
• Multichannel read-out for arrays of metallic magnetic calorimeters
• Low Background Micromegas in CAST

Cited by in corpus (7)

• A Review of X-ray Microcalorimeters Based on Superconducting Transition Edge Sensors for Astrophysics and Particle Physics
• Superconducting detectors for rare event searches in experimental astroparticle physics
• Towards Precision Muonic X-Ray Measurements of Charge Radii of Light Nuclei
• Axion Helioscopes as Solar Thermometers
• MMC Array to Study X-ray Transitions in Muonic Atoms
• Digging into Axion Physics with (Baby)IAXO
• Reference Quadrupole Moments of Transition Elements from Lamb Shifts in Muonic Atoms