MOA-cam3: a wide-field mosaic CCD camera for a gravitational microlensing survey in New Zealand
MOA-cam3: a wide-field mosaic CCD camera for a gravitational microlensing survey in New Zealand
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DOI：
10.1007/s10686-007-9082-5
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发表时间：
2008-10-01
影响因子：
3
通讯作者：
Yock, P. C. M.
中科院分区：
文献类型：
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作者：
Sako, T.;Sekiguchi, T.;Yock, P. C. M.
我们研制了一种宽视场拼接CCD相机MOA-cam3，安装在天体物理微透镜观测（MOA） 1.8 m望远镜的主焦上。该相机由10个E2V CCD4482芯片组成，每个芯片具有2kx4k像素，单次曝光可覆盖2.2度(2)的视野。光学系统得到了很好的优化，可以在宽视场内实现均匀的成像质量。芯片在-80摄氏度的低温下不断冷却，在此温度下，典型的1-3分钟暴露的暗电流噪声可以忽略不计。CCD输出电荷由GenIII系统（天文研究相机公司）转换为16位数字信号，读出时间在25秒内。2-3 ADU （rms）的读出噪声也可以忽略不计。我们为有效的微透镜调查准备了一个宽带红色滤光片，也为标准的天文研究准备了贝塞尔V， I滤光片。微透镜研究已经进入了一个新时代，需要更多的统计数据和更快速的警报来捕捉奇异的光曲线。我们的新系统是实现这两个要求的有力工具。
We have developed a wide-field mosaic CCD camera, MOA-cam3, mounted at the prime focus of the Microlensing Observations in Astrophysics (MOA) 1.8-m telescope. The camera consists of ten E2V CCD4482 chips, each having 2kx4k pixels, and covers a 2.2 deg(2) field of view with a single exposure. The optical system is well optimized to realize uniform image quality over this wide field. The chips are constantly cooled by a cryocooler at -80 degrees C, at which temperature dark current noise is negligible for a typical 1-3 min exposure. The CCD output charge is converted to a 16-bit digital signal by the GenIII system (Astronomical Research Cameras Inc.) and readout is within 25 s. Readout noise of 2-3 ADU (rms) is also negligible. We prepared a wide-band red filter for an effective microlensing survey and also Bessell V, I filters for standard astronomical studies. Microlensing studies have entered into a new era, which requires more statistics, and more rapid alerts to catch exotic light curves. Our new system is a powerful tool to realize both these requirements.