Megacam: paving the focal plane of the MMT with silicon

被引：17

作者：

McLeod, BA ^{[1
]}

Gauron, TM ^{[1
]}

Geary, JC ^{[1
]}

Ordway, MP ^{[1
]}

Roll, JB ^{[1
]}

机构：

[1] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA

来源：

OPTICAL ASTRONOMICAL INSTRUMENTATION, PTS 1 AND 2 | 1998年 / 3355卷

关键词：

CCDs; imaging; cameras; astronomy; telescope guiding;

D O I：

10.1117/12.316779

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Megacam is a 36 CCD mosaic camera that will cover a 24' x 24' field of view at the f/5 wide-field focus of the converted 6.5 m Multiple Mirror Telescope. The mosaic is a 9 x 4 array of thinned 2048 x 4608 pixel CCDs with 13.5 mu m pixels. The CCDs are dual-output EEV devices in a custom package to allow the devices to be closely butted on all four sides. The dewar will be mounted to a 2 m diameter assembly that contains the filter wheels (for 30 x 30 cm filters) and the shutter. Telescope guiding will be accomplished with two additional CCDs mounted at the edges of the focal plane. The guider CCDs will be operated slightly defocused, one on either side of focus, to allow simultaneous focusing and guiding. Guide stars will be selected by reading out the full guider frame, after which only a small area surrouding the guide star will be read out. Our simulations show that the defocused guide star images will also be useful for low order wavefront sensing, allowing corrections to the telescope collimation. We are developing a new CCD controller capable of reading the full Megacam in 24 seconds. This controller will also be used to operate the guide chips.

引用

页码：477 / 486

页数：4