École Nationale Supérieure de
Techniques Avancées

Abstract

Kinetic Inductance Detectors (KIDs) have been extensively studied over the past fifteen years and are now widely used in ground-based millimeter-wave astronomy. Their high sensitivity and operating frequency range make them particularly well-suited for probing the absorption properties of interstellar dust. In this work, I have developed a new type of KID, optimized for wideband absorption (over 50% between 120 GHz and 370 GHz) and less sensitive to fabrication uncertainties. These detectors will provide reference measurements of interstellar dust absorption over frequency ranges that remain poorly documented. I have demonstrated the feasibility of such absorption measurements using NIKA2-type KID arrays, obtaining asymptotic absorption curves that extend previous results on forsterite (Mg_2SiO_4) dust samples. The mass absorption coefficient was derived for three dust temperatures (10 K, 20 K, and 30 K), and is described by an asymptotic model of the form \kappa_0(\lambda/\lambda_0)^{-\beta}, with \beta_{10K}=2.70, \beta_{20K}=2.72, and \beta_{30K}=2.40. Moreover, we observe a linear increase of the mass absorption coefficient with dust temperature.