Early commissioning results of slit mask integral field units on the Southern African Large Telescope

Sabyasachi Chattopadhyay; Matthew A. Bershady

doi:10.1117/12.3017822

18 July 2024 Early commissioning results of slit mask integral field units on the Southern African Large Telescope

Sabyasachi Chattopadhyay, Matthew A. Bershady

Proceedings Volume 13096, Ground-based and Airborne Instrumentation for Astronomy X; 130962R (2024) https://doi.org/10.1117/12.3017822
Event: SPIE Astronomical Telescopes + Instrumentation, 2024, Yokohama, Japan

Conference Poster

Abstract

Three fibre feed integral field units (IFUs), called Slit Mask IFUs (SMI), are being developed in the SAAO fibre-lab for the Robert Stobie Spectrograph (RSS). The smaller, 200 micron fibre IFU (SMI-200) has 309 x 0.9 arcsec diameter spatial elements covering an elongated hexagonal footprint of 18 × 23 arcsec is now being commissioned. The larger, 300 (400) micron fibre IFU, SMI-300 (SMI-400), has 221 × 1.35 arcsec (178 × 1.8 arcsec) diameter spatial elements covering an on-sky area of 18 × 29 sq. arcsec (21 × 44 sq. arcsec). In all SMI units there are two groups of 13 fibres offset by roughly 50 arcsec on either side of the primary array to sample sky. SMI-200 provides a median spectral resolution of 2400 at Hα wavelengths in a low resolution mode simultaneously covering 370 to 740 nm. At a higher grating angles the SMI-200 delivers spectral resolution up to 10,000. A future red spectrograph arm for RSS will extend the simultaneous wavelength coverage up to 900 nm at a median resolution of 6000 for the same IFU. With this upcoming red arm and with the fibre-fed, near-infared spectrograph NIRWALS on SALT, SMI-300 enables wavelength coverage from blue to NIR wavelengths at the same spatial resolution and footprint. The SMI units are inserted in the same fashion as the existing long-slit cassettes at the SALT focal plane. Prismatic fold mirrors direct the focal plane into the fibre IFU and then back into the RSS collimator after the fibres are routed 180 deg within the cassette and formatted into a pseudo-slit. Fold-prisms ensure that the spectrograph collimator continues to see the same focal plane. In this paper we report the laboratory characterization and on-sky commissioning-performance of the first Slit Mask IFU, SMI-200.

(2024) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

Sabyasachi Chattopadhyay and Matthew A. Bershady "Early commissioning results of slit mask integral field units on the Southern African Large Telescope", Proc. SPIE 13096, Ground-based and Airborne Instrumentation for Astronomy X, 130962R (18 July 2024); https://doi.org/10.1117/12.3017822

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available