3.6 m DOT
The 3.6m Devasthal Optical Telescope is a custom-built instrument of great complexity. This telescope has the distinction of being largest telescope in India for study of celestial objects at optical wavelengths. It is a national facility installed at Devasthal in the district of Nainital, India. It was commissioned in the year 2016 and is being maintained and operated by ARIES. The 3.6m DOT facility consists of a modern 3.6 meter optical new technology telescope, a suite of instruments, an Aluminium coating plant, a control room and a data center. The back-end instruments of telescope provide spectral and imaging capabilities at visible and near-infrared bands.
Observers/Proposers/Authors are encouraged to mention 3.6m DOT in title or abstract of the research publications and also put an acknowledgement as "Based on observations obtained at the 3.6m Devasthal Optical Telescope (DOT), which is a National Facility run and managed by Aryabhatta Research Institute of Observational Sciences (ARIES), an autonomous Institute under Department of Science and Technology, Government of India.". In addition, It may be required to cite a paper describing instrument set-up etc., as provided in the webpages of the respective instruments.
The observing time on 3.6m Devasthal Optical Telescope is apportioned as follows : 60% open time on competitive basis to any astronomer working in an Indian Institution; 33% guaranteed time for astronomers from ARIES and 7% guaranteed time for Belgian astronomers subject to the scientific merit of the proposals. About 10% of the available science time, will be reserved as Director’s Discretionary Time for allocation by the Director, ARIES.
Observing proposals have to be submitted using the DOT Online Proposal Submission System (DOPSES) at the URL http://dopses.aries.res.in. The table below specifies some of the important dates.
| Cycle | Call for Proposal | Deadline for Submission |
| C1 (February - May) | 1st November | 1st December |
| C2 (October - January) | 1st July | 1st August |
Proposers requesting time on telescope are advised to browse through the pages of Instruments, Telescope and other sub-menus for Latest Update.
OBSERVING SCHEDULE
Proposal Deadline: Thursday, August 1, 2024, 17:00:00 IST
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from the 1st of October 2024 to the 31st of January 2025 (DOT-2024-C2). The deadline for receiving these proposals is 1st August 2024, 17:00:00 hrs Indian Standard Time (UTC+5.5 hrs). India has a 93% share in the telescope time, of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation System (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2024-C2:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. Switching the ports within a minute is possible using a fold mirror. In principle, a set of three instruments can be mounted with the telescope and used nearly simultaneously. The side-port2 is free at the moment. The TIRCAM2 is permanently mounted on the side-port1 of the telescope, and it is always available for observation, whereas other instruments are mounted one at a time on the main axial port.
For cycle DOT-2024-C2, the mounting sequence for main-port instruments is ADFOSC and then TANSPEC for two months each. The actual period on the telescope will be governed by users' requirements. Optical Imager will be available as an optional instrument and will be made available if demanded. Proposers requesting time on telescope via DOPSES are advised to browse through the Instruments and Telescope pages for the latest updates on current sensitivities and upgrades.
OBSERVING SCHEDULE
Proposal Deadline : Friday, December 1, 2023, 23:59:59 IST (mid-night)
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from 1st of February 2024 to 31st of May 2024 (DOT-2024-C1). The deadline for receiving these proposals is midnight of 1st December, 2023, 23:59:59 hrs Indian Standard Time (UTC+5.5 hrs). India has 93% share in the telescope time of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation system (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2024-C1:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. It is possible
to switch the ports within a minute using a fold mirror. In principle, a set of three instruments can be mounted with the telescope
and used near simultaneously. The side-port2 is free at the moment. The TIRCAM2
is permanently mounted on the side-port1 of the telescope and it is always available for observations, whereas other instruments
are mounted one at a time on the main axial-port.
For cycle DOT-2024-C1, the mounting sequence for main-port instruments is as follows : ADFOSC, IMAGER and TANSPEC. The actual period on telescope will be governed by the requirements by users. Proposers requesting time on telescope via DOPSES are advised to browse through the pages of Instruments and Telescope for Latest Update on current sensitivities and upgrade.
OBSERVING SCHEDULE (Revision-1)
OBSERVING SCHEDULE
Proposal Deadline : Tuesday, August 1, 2023, 23:59:59 IST (mid-night)
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from 1st of October 2023 to 31st of January 2024 (DOT-2023-C2). The deadline for receiving these proposals is midnight of 1st August, 2023, 23:59:59 hrs Indian Standard Time (UTC+5.5 hrs). India has 93% share in the telescope time of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation system (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2023-C2:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. It is possible
to switch the ports within a minute using a fold mirror. In principle, a set of three instruments can be mounted with the telescope
and used near simultaneously. The side-port2 is free at the moment. The TIRCAM2
is permanently mounted on the side-port1 of the telescope and it is always available for observations, whereas other instruments
are mounted one at a time on the main axial-port.
For cycle DOT-2023-C2, the mounting sequence for main-port instruments is as follows : ADFOSC, IMAGER and TANSPEC. The actual period on telescope will be governed by the requirements by users. Proposers requesting time on telescope via DOPSES are advised to browse through the pages of Instruments and Telescope for Latest Update on current sensitivities and upgrade.
OBSERVING SCHEDULE
Proposal Deadline : Thursday, December 1, 2022, 23:59:59 IST (mid-night)
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from 1st of February 2023 to 31st of May 2023 (DOT-2023-C1). The deadline for receiving these proposals is midnight of 1st December, 2022, 23:59:59 hrs Indian Standard Time (UTC+5.5 hrs). India has 93% share in the telescope time of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation system (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2023-C1:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. It is possible
to switch the ports within a minute using a fold mirror. In principle, a set of three instruments can be mounted with the telescope
and used near simultaneously. The side-port2 is free at the moment. The TIRCAM2
is permanently mounted on the side-port1 of the telescope and it is always available for observations, whereas other instruments
are mounted one at a time on the main axial-port.
For cycle DOT-2023-C1, the mounting period for main-port instruments is as follows : ADFOSC (February 01 to March 26); IMAGER (March 27 to April 2); and TANSPEC (April 3 to May 31). Proposers requesting time on telescope via DOPSES are advised to browse through the pages of Instruments and Telescope for Latest Update on current sensitivities and upgrade.
OBSERVING SCHEDULE
Proposal Deadline : Monday, August 1, 2022, 17:00 IST
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from 1st of November 2022 to 31st of January 2023 (DOT-2022-C2). The deadline for receiving these proposals is 17:00 hrs Indian Standard Time (UTC+5.5 hrs), 1st August, 2022. India has 93% share in the telescope time of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation system (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2022-C2:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. It is possible
to switch the ports within a minute using a fold mirror. In principle, a set of three instruments can be mounted with the telescope
and used near simultaneously. The side-port2 is free at the moment. The TIRCAM2
is permanently mounted on the side-port1 of the telescope and it is always available for observations, whereas other instruments
are mounted one at a time on the main axial-port.
For cycle DOT-2022-C2, the IMAGER, ADFOSC and TANSPEC would be available for the main-port and the precise dates of their mounting period on telescope shall be derived from the demand for instruments by proposers.
Proposers requesting time on telescope via DOPSES are advised to browse through the pages of Instruments and Telescope for Latest Update
on current sensitivities and upgrade.
OBSERVING SCHEDULE (Revision-1)
OBSERVING SCHEDULE
Proposal Deadline : Wednesday, December 1, 2021, 17:00 IST
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from 1st of February 2022 to 15th of May 2022 (DOT-2022-C1). The deadline for receiving these proposals is 17:00 hrs Indian Standard Time (UTC+5.5 hrs), 1st December, 2021. India has 93% share in the telescope time of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation system (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2022-C1:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. It is possible
to switch the ports within a minute using a fold mirror. In principle, a set of three instruments can be mounted with the telescope
and used near simultaneously. The side-port2 is free at the moment. The TIRCAM2
is permanently mounted on the side-port1 of the telescope and it is always available for observations, whereas other instruments
are mounted one at a time on the main axial-port.
For cycle DOT-2022-C1, a tentative instrument sequence for main axial-port is as follows : ADFOSC shall be available during February to mid March and the TANSPEC would be available from mid March to mid May. The precise dates may be derived from the demand for instruments by proposers. There is no plan to mount IMAGER in this cycle, however, in case of large demand it can be mounted for a week
during middle of March.
Proposers requesting time on telescope via DOPSES are advised to browse through the pages of Instruments and Telescope for Latest Update
on current sensitivities and upgrade.
OBSERVING SCHEDULE (Revision-2)
OBSERVING SCHEDULE (Revision-1)
OBSERVING SCHEDULE
Proposal Deadline : Monday, August 2, 2021, 17:00 IST
ARIES invites proposals from the astronomical community of India and Belgium for observations with 3.6m DOT for the observing cycle from 1st of October 2021 to 31st of January 2022 (DOT-2021-C2). The deadline for receiving these proposals is 1700 hrs Indian Standard Time (UTC+5.5 hrs), 2nd August, 2021. India has 93% share in the telescope time of which 33% is guaranteed to ARIES, and the Belgian share is 7%. The Principal Investigator of the proposals should have affiliations at Indian or Belgian academic institutions and/or universities. The Science observing proposals can be submitted online via the DOT Online proposal management and evaluation system (DOPSES) available at http://dopses.aries.res.in
Notes for proposers of Cycle DOT-2021-C2:
The 3.6m DOT has three cassegrain ports viz. main axial-port, side-port1 and side-port2. It is possible
to switch the ports within a minute using a fold mirror. In principle, a set of three instruments can be mounted with the telescope
and used near simultaneously. The side-port2 is free at the moment. The 3.6m DOT currently offers four instruments (IMAGER, TIRCAM2,
ADFOSC, TANSPEC) for carrying out high resolution imaging and low resolution spectroscopic observations of celestial sources. The TIRCAM2
is permanently mounted on the side-port1 of the telescope and it is always available for observations, whereas other instruments
are mounted one at a time on the axial-port.
Instrument sequence for cycle DOT-2021-C2 : Tentatively, IMAGER shall be available during October, TANSPEC during October
to December, then IMAGER in December and ADFOSC during December 2021 to January 2022. The final sequence as well as the
precise dates may be derived from the demand for instruments by proposers.
Proposers requesting time on telescope via DOPSES are advised to browse through the pages of Instruments and Telescope for Latest Update
on current sensitivities and upgrade.