A new gamma-ray sensor, which could be employed in harsh underwater conditions, was developed using YAlO₃(Ce) single crystal and carbon nanotube reinforced polyetheretherketone (CNT/PEEK). The sensor is compact, highly sensitive and stable, by providing real-time gross counts and an accumulated spectrum for fresh, saline, or contaminated water conditions. The sensor was tested in a water tank for quantification of the limit of detections. The Φ51 × 51 mm² YAlO₃(Ce) crystal exhibits a nearly perfect proportionality with a correlation of over 0.999 in terms of light yield per energy and possesses a high energy resolution. The chemically stable CNT/PEEK window material further enhances the detection efficiency by minimizing the background counts from penetrating gamma-rays. Data timeliness was obtained for regulation-based minimum detectable activity targets within 300 s. For a source-detector distance of up to 300 mm in water, the gross counts demonstrate the existence of radionuclides (Cs-137 and Co-60), owing to their higher efficiency (max. ~15 times) than those of the photopeak counts. Such differences between efficiency values are more likely in water than in air because of the high density of water, resulting in an increased build-up of scattered photons. The proposed sensor is suitable for autonomous underwater systems.

中文翻译：

---

使用YAlO3（Ce）单晶和CNT / PEEK在苛刻的水下条件下具有高灵敏度和稳定性的γ射线传感器

使用YAlO ₃（Ce）单晶和碳纳米管增强的聚醚醚酮（CNT / PEEK），开发了一种可以在恶劣的水下条件下使用的新型伽马射线传感器。该传感器结构紧凑，高度灵敏且稳定，可提供实时的总计数和淡水，盐水或污水污染情况下的累积光谱。在水箱中对传感器进行了测试，以定量检测极限。Φ51×51 mm ² YAlO ₃（Ce）晶体显示出几乎完美的比例，每单位能量的光通量相关性超过0.999，并且具有高能量分辨率。化学稳定的CNT / PEEK窗口材料通过最小化穿透伽马射线的背景计数，进一步提高了检测效率。在300 s内获得了基于法规的最小可检测活动目标的数据及时性。对于在水中最远距离为300 mm的源-探测器，总计数表明存在放射性核素（Cs-137和Co-60），这是因为它们的效率（最大〜15倍）比光电峰计数高。 。由于水的高密度，效率值之间的这种差异在水中比在空气中更容易发生，从而导致散射光子的堆积增加。