| Name: | Nitish SIngh |
| Affiliation: | Indian Institute of Astrophysics, Bengaluru |
| Conference ID : | ASI2024_224 |
| Title : | Multi-object spectroscopy with Vainu Bappu Telescope: Design, Development, and Lab testing of Wide Field Corrector unit at IIA |
| Authors : | Nitish Singh,
S. Sriram,
Bharat Kumar Yerra |
| Authors Affiliation: | Indian Institute of Astrophysics Bengaluru, INDIA |
| Mode of Presentation: | Oral |
| Abstract Category : | Facilities, Technologies and Data science |
| Abstract : | Vainu Bappu telescope (VBT) is operated by the Indian Institute of Astrophysics (IIA), which is equipped with two spectrographs: the OMR spectrograph at the Cassegrain focus and the high-resolution echelle spectrograph at the prime focus. However, due to the presence of the replaceable heavy VBT secondary mirror unit, there are limitations in using both spectrographs simultaneously in a single night. We have designed a wide-field corrector (WFC) unit to overcome this challenge. This WFC consists of three lenses that can correct a 0.5-degree field of view (FoV) at the prime focus of VBT, wherein the central lens can act as an atmospheric dispersion corrector. The grinding and polishing of WFC lenses are performed in the IIA optics lab. Results from the lab testing are promising with the wavefront errors in the order of lambda/30. To link the OMR spectrograph at the prime focus, we have designed a fiber interface and conducted the laboratory testing. In this talk, I will present the results from the new WFC unit and the development of the fiber interface unit to the OMR spectrograph to feed the light from the prime focus. I also discuss the possibilities of accommodating more fibers/fiber bundles to the WFC unit that can enable multi-object spectroscopy of point and extended objects. |
