WSO-UV Field Camera Unit (FCU)

The FCU is mounted on top of the optical bench, below the primary mirror of the T-170M. The FCU has two channels, each fed by an independent pick off mirror. The far UV (FUV) channel has capabilities for high resolution imaging. Also, some low dispersion spectroscopic capabilities around Lyman-alpha (121.5 nm) and the C IV resonance transition at 155.0 nm are available. The UV-optical (UVO) channel is designed for wide field imaging from 200 to 600nm. The main features of the FCU are summarized in the table below.

Main features of the WSO-UV FCU

The effective area of the FCU is shown in the figure below and the preliminary filter list in the associated table. FCU PDR will be at the end of 2018. There may be slight changes in the quoted performances.

Effective area of the FCU

FCU operational Modes

Imaging.

The beam is focused on the selected channel (FUV or UVO).

Imaging Time-tag.

Photon counting image mode on 10x10 pixels on the detector. Photons will be count at a pace of at most 40 ms/read-out over 5 minutes. It may require to include a previous acquisition image to set the target in a pre-defined area of fast read-out.

Spectroscopy.

The beam is directed to the prisms. It may require refocusing the camera.

Spectroscopy Time-Tag.

Photon counting slitless spectroscopy mode on 20x300 pixels on the detector. Photons will be count at a pace of at most 40 ms/read-out over 5 minutes. It may be require including a previous acquisition image to set the target in a pre-defined area of fast read-out.

Parallel-UVO.

FCU/UVO Channel is used in parallel mode while using any other instrument.

Filters and dispersive elements in the WSO-UV/FCU