# Scientific potential of the Indo-Belgian 3.6-m DOT in the field of Galactic Astronomy

## TL;DR

The 3.6-m Devasthal Optical Telescope (DOT) in India, a joint Indo-Belgian project, has demonstrated high-quality optical and near-infrared observations, showing promise for advanced galactic astronomy research with further instrument upgrades.

## Contribution

This paper reports on the successful deployment, performance, and scientific potential of the Indo-Belgian 3.6-m DOT, highlighting its capabilities and future prospects in galactic astronomy.

## Key findings

- Achieved 0.4 arcsecond angular resolution.
- Maintained atmospheric seeing conditions comparable to previous measurements.
- Demonstrated potential for internationally competitive scientific research.

## Abstract

India and Belgium have jointly established two 4 meter class optical telescopes at Devasthal located in Nainital, India. After successful installation of the 3.6-m modern new technology Devasthal Optical Telescope (DOT) in 2015, it was technically activated by premiers of both countries from Brussels on March 30, 2016. Since then, the 3.6-m DOT has been used for both optical and near-Infrared (NIR) observations for a number of research proposals. The best angular resolution achieved is 0\farcsec4 indicating that the optics of the 3.6-m DOT is good and capable of providing images of the celestial bodies with sub-arc-second resolution. The observations provide proof that the care taken in the construction of the telescope dome building has paid a rich dividend as their thermal mass is so low that it has not degraded the natural atmospheric seeing at Devasthal measured about two decades ago during 1997 to 1999 using differential image motion monitor. A few preliminary scientific results obtained from recent observations are presented along with performance and global potential of the 3.6-m DOT in the field of galactic astronomy. The 3.6-m DOT is capable of providing internationally competitive science once high resolution spectrograph and other planned modern back-end instruments become operational. Geographical location of the observatory has global importance for the time domain and multi-wavelength astrophysical studies.