Future Capabilities (Can be used from S15A onwards):
In addition to the currently commissioned modules on SCExAO, we have begun phase II engineering activities. These will bring online the following modules:
- The high-order wavefront sensor:
The high order wavefront sensor is based on a non-modulated Pyramid wavefront sensor and operates in the visible region (600-900 nm). This sensor is very sensitive to high spatial frequencies, a key requirement for achieving high Strehl ratios. It operates in conjunction with our 2000 element deformable mirror in order to offer a very high level of wavefront correction (90%+ Strehl ratios in good seeing). The sensor has been operated in closed-loop on the first 10 Zernike modes and the first 900 Fourier modes in a laboratory environment. Initial on-sky data was collected with the Zernike loop closed in December of 2014, but the seeing was very poor (>1.2") so the results were not convincing. Our aim is to commission this module by the end of 2014. We have just received funding to purchase the US$220k FirstLight OCAM2K camera which will offer a frame rate of 3.7 kHz with binning, 0.3e- read noise, <0.01e- dark current and very high quantum efficiency between 500 and 900 nm. This camera will maximize the performance of the high-order wavefront sensor and is an exciting new development.
Stands for the Visible Aperture Masking Polarimetric Interferometer for Resolving Exoplanetary Signatures and operates in the visible with the left over light from the wavefront sensor (600-900 nm). This module allows sub-diffraction limited imaging, owing to the interferometry aspect, in the visible enabling angular resolutions approaching 10 mas! In addition the exquisite level of polarization calibration offered enables very low levels of polarisability, like those from scattering components such as disks around young stars and dust shells around old stars to be studied in detail. VAMPIRES has undergone initial on-sky testing on July 25th 2013 and showed that high levels of polarization systematic calibration are possible. It has also measured the size of a super giant and the separation of a known binary. Our aim is to commission this module by the end of 2014. This module is being developed by the University of Sydney.
FIRST is a unique interferometer operating in the visible which relies on an array of single-mode fibers to remap the pupil and prepare the beams for downstream beam combination. FIRST allows imaging at sub-diffraction limited scales with spectral information. FIRST has had previous engineering and science runs at the Lick Observatory (Shane Telescope) and has been reconfigured for operation within SCExAO. We aim to have FIRST commissioned by the end of 2014. More details and information about the FIRST module can be found on the collaborators page.
- Fourier lucky imaging:
Fourier lucky imaging is a technique whereby the strongest Fourier components are taken from each image in a stack of fast frame rate images and a single image is synthesized from the Fourier spectrum. In this way it is possible to do diffraction limited imaging even when the seeing is terrible. This module is currently running in the background at each observing run, collecting data, but we aim for an extensive upgrade in late 2014 which will include multiple spectral channels.
- PIAA Complex mask coronagraph:
The PIAACMC is an upgrade to the PIAA coronagraph and offers better performance and suppression over a broad bandwidth (i.e. its achromatic across y-K band). It offers a smaller inner working angle (1 λ/D) than the current PIAA coronagraph. This module will be installed and commissioned some time during 2014 in preparation for 2015 science.
- 8-Octant Phase Mask Coronagraph:
We will install an 8-octant Phase Mask coronagraph and pupil reformatting lenses in mid-2014. This will extend the range of coronagraphs available to potential users. The 8-octant phase mask is being developed by the team at Hokkaido University.
- Infrared polarimetry:
In order to match the capabilities of the current high contrast imager at Subaru, HiCIAO, which SCExAO will replace, we will install a Wollaston prism on the IR channel for polarimetric observations. Work has not begun on this yet but we hope to have this running by late 2014 as well.
The next engineering runs include the 14th and 15th of April and the 2nd and 4th of June. We have a SEEDS science night also scheduled for the 5th of June.