Development of Calorimetric Low-Temperature Detectors for Application in Heavy Ion Physics

微量热计检测进入的粒子将其动能转化为热量后吸收塔的温度变化。这种工作原理在能量分辨率、探测效率、能量阈值和辐射硬度方面比传统探测器有相当大的优势。用微量热计探测X射线，在1-100keV能量范围内，相对能量分辨率为1-3‰。对于直接的、能量敏感的重离子探测，获得了1-7‰的相对分辨率，这意味着与传统的重离子探测器相比提高了一个数量级。拟议的艾美诺特研究小组将开发和改装专门用于重离子物理实验需要的微量热计。其中一个重点是用于重离子直接能量灵敏探测的微量热计：主要目的是研究和改进这类探测器在0.1 MeV/u以下的能量范围内的性能，这一问题到目前为止还没有得到解决。这种探测器用于精确测定固体中重离子的能量损失，将为电离、电荷交换或原子核的直接弹性散射等能量沉积机制提供重要信息。用于探测X射线的微量热计将在新建成的离子陷阱设施HITRAP(Gesellschaft für Schwerion enforschung，Darmstadt)通过精确测量高电荷重离子(Lamb Shift)中的电子跃迁能来探测量子电动力学。特别是对于不稳定核，这种方法还将打开一种确定核电荷半径的替代方法。

Microcalorimeters detect the temperature change of an absorber after an incoming particle has deposited its kinetic energy as heat. This operation principle provides considerable advantage over conventional detectors with respect to energy resolution, detection efficiency, energy threshold and radiation hardness. The detection of X-rays with microcalorimeters achieves a relative energy resolution of 1–3 ‰ in the energy regime of 1–100 keV. For the direct, energy-sensitive detection of heavy ions, a relative resolution of 1–7 ‰ has been obtained, which means an improvement of one order of magnitude as compared to conventional heavy-ion detectors.The proposed Emmy-Noether research group will develop and adapt microcalorimeters especially for the needs of heavy-ion physics experiments. One focus lies on microcalorimeters for the direct energy-sensitive detection of heavy ions: The main aim is to investigate and improve the performance of such detectors in the energy range below 0.1 MeV/u, which has not been addressed up to now. The application of such detectors for the precise determination of energy losses of heavy ions in solids will provide important information on the energy deposition mechanisms like ionization, charge exchange or the direct elastic scattering of nuclei.Microcalorimeters for the detection of X-rays will be applied at the newly constructed ion-trap facility HITRAP (Gesellschaft für Schwerionenforschung, Darmstadt) to probe Quantum Electrodynamics by precise measurements of the electron transition energies in highly-charged heavy ions (Lamb shift). Especially for unstable nuclei, this method will also open access to an alternative way to determine nuclear charge radii.