학술논문
From ECHo-1k to ECHo-100k:Optimization of High-Resolution Metallic Magnetic Calorimeters with Embedded 163 Ho for Neutrino Mass Determination
Document Type
Original Paper
Author
Source
Journal of Low Temperature Physics. 209(5-6):779-787
Subject
Language
English
ISSN
0022-2291
1573-7357
1573-7357
Abstract
The ECHo experiment aims at determining the effective electron neutrino mass by analyzing the endpoint of the 163 Ho electron capture spectrum. High energy resolution detectors with a well-tailored detector response are the essential ingredient for the success of the ECHo experiment. Metallic magnetic calorimeter arrays enclosing 163 Ho have been chosen for the ECHo experiment. The first MMC array, ECHo-1k, showed excellent performances with an average energy resolution of 5.5 eV FWHM @ 5.9 keV. Based on the results obtained with the ECHo-1k array, optimization studies have paved the way towards a new detector design for the next experimental phase, ECHo-100k. The ECHo-100k chip features an optimized single pixel design to improve the detector performance as well as an upgraded on-chip thermalization layout. The newly fabricated ECHo-100k detectors have been fully characterized at room temperature, at 4 K and at millikelvin temperature. The obtained results show that the ECHo-100k array achieved the expected performance with an average energy resolution of 3.5 eV FWHM @ 5.9 keV, fulfilling the requirements for the ECHo-100k experimental phase.