The PFS Science Team has established a working group for each scientific objective and has vigorously discussed what interesting science cases are to exploit the strengths of PFS and how we optimize the survey observation accordingly (visit our past post and our official web site for more details about science objectives of the project). Based on these discussions we have developed an… Read more »
We reported that Metrology Camera System had been installed to the Subaru Telescope for the test. MCS, however, is not the only instrument for PFS to have been installed to the telescope. The prototype fiber cable was also routed on the telescope to test the optical performance about a half year ago. The work was done a little long time… Read more »
In this article, we are going to show recent news at Laboratoire d’Astrophysique de Marseille (LAM, France), where the first PFS Spectrograph module is being integrated. The assemblies for the first spectrograph module, such as the visible-blue and red cameras, optical bench and optical components have been delivered to LAM, as we showed in the previous article. Since then, the fiber… Read more »
Since we published the article about the delivery of the Metrology Camera System (MCS) to Subaru Telescope in May this year, the member mainly from ASIAA (Academia Sinica Institute of Astronomy and Astrophysics, Taiwan) have visited Subaru Telescope a few times, in order to finalize the integration and proceed the on-site tests. In this article, we are going to talk… Read more »
On June 10-15 2018, there was the SPIE conference titled “Astronomical Telescope and Instrumentation” at Austin Convention Center, in Austin, Texas, USA. This is a big international conference of astronomical instrumentation held every two years. Hundreds of presentations are given about a wide range of topics across ground-based facilities, space missions, and R&D studies. Like many other projects did so… Read more »
To talk about this story, one should go back in time a little … Some time ago, the Metrology Camera System was shipped over the Pacific Ocean(from Taiwan to Hawaii). In fact, around the same time, the first fiber positioner module was also shipped over the Pacific Ocean, from California to Taiwan. The PFS instrument catches the light from galaxies and… Read more »
About one month has passed since Metrology Camera was shipped from Taiwan. Now it has arrived at Subaru Telescope at Maunakea in Hawaii. After shipping, from 23 April 2018, members from Academia Sinica, Institute of Astronomy and Astrophysics (ASIAA) visited to Hawaii Observatory of National Astronomical Observatory of Japan for final development. At Hilo base, ASIAA inspected Metrology Camera and… Read more »
It has been about 3 months since the first blue camera cryostat was shipped to France. In this post, we are showing the updates on development of the Spectrograph systems. At Laboratorie d’Astorophysique de Marseille (LAM), we finished the performance test using only a red camera unit, and started fully integrating the first spectrograph module (called SM1). We have already… Read more »
One of the PFS instrument “Metrology Camera” was finally shipped from Taiwan to Hawaii!! Metrology Camera is an instrument used to measure the fibers position while we configure fibers to target objects. Academia Sinica Institute of Astronomy and Astrophysics (ASIAA) in Taiwan has the responsibility for Metrology Camera development, and they tested its performances before shipping in the last a… Read more »
Written by Masayuki Tanaka (NAOJ) PFS survey is going to collect a huge amount of data. Thanks to the high multiplexity with 2400 fibers, we are going to collect as many as 67,000 spectra in a single night according to the current survey plan. In addition, we will measure a variety of physical parameters — redshifts of galaxies, strengths of emission and absorption… Read more »
We will observe ~2400 objects using four identical spectrograph modules, each of which acquires ~600 spectra of astronomical sources and calibration sources. Each module covers wide wavelength range on visible and near-infrared band (380 — 1260 nm). To achieve this, the module has 3 camera units; visible-blue, visible-red and near-infrared. The light of each band is introduced by using two “dichiroic mirrors”, which split the light at a given wavelength.
PFSでは約2400個の天体を観測しますが、4つの同型の分光器を用いてそれぞれ600本のスペクトルを取得します。各分光器は可視光域から近赤外域までの広い波長範囲 (380 から1260 nm) をカバーする為、「可視光域青用」、「可視光域赤用」、「近赤外域用」の3つのカメラユニットを持っています。3つのカメラには、特定の波長で光を分けることのできるダイクロイックミラーを2つ用いて、光を導入します。
To measure the fibers position on the focal plane, “Metrology Camera System” is attached on the Cassegrain focus of Subaru telescope. Looking up to the prime focus (see this image from HSC blog for clear image), this camera takes a image of back-illuminated fibers. Thanks to a large format of ~50 M pixels CMOS sensor, this camera can acquire all ~2400 fiber spots in a single exposure. The camera system is also designed to execute the process from exposure to measurement of fiber centroids within 5 seconds. Effective measurement of the fibers position enables us to shorten overhead for fiber configuration and execute large statistical survey observation.
The Metrology Camera System will be delivered to Subaru in early 2018.
焦点面上のファイバーの位置を測定する為に、『メトロロジカメラシステム』をすばる望遠鏡のカセグレン焦点に取り付けます。このカメラは焦点面を見上げるようにして後ろ側から照らされたファイバーの画像を取得します(イメージ的にはこちらの画像 (HSCブログより) のような感じです)。メトロロジカメラには50Mピクセルの大判のCMOSセンサが搭載されているため、約2400本のファイバー像をたった一回の露出で得ることができます。また、画像の取得から各ファイバーの位置測定までを5秒以内に行うように設計されています。このようにファイバーの効率よく位置を測定することで、ファイバーの配置など観測準備にかかる時間をなるべく短くし、大規模サーベイ観測を行うことができるのです。
メトロロジカメラシステムは2018年4月にすばる望遠鏡へ搬送されるました。
The Spectrograph Clean Room is a room whose size is 6.7 m wide, 8.6 m long ,and 3.6 m high. Four PFS spectrographs will be accommodated in the clean room. To stabilize the spectrograph performance, the temperature in the room will be controlled at 5 +- 1 degree Celsius. Besides, a crane with capability of 500 kg is installed for assembly and maintenance of the Spectrograph.
分光器設置室は、すばる望遠鏡ドーム棟4階に建設された部屋で、幅6.7m × 奥行8.6m × 高さ 3.6 mの大きさです。 PFSの4台の分光器がこの部屋に設置されます。分光器の安定性を図るために、部屋全体が5±1℃の範囲で温度管理されます。また、分光器の設置やメンテナンス用に室内には耐荷重500kgのクレーンが設置されています。
