Semester 2020B Call for Proposal | Gemini Observatory

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Semester 2020B Call for Proposal

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Gemini Observatory invites its community to propose scientific investigations for the 2020B semester, 1 August 2020 - 31 January 2021

The table below shows submission deadlines for (i) all Gemini Participants, (ii) the Subaru community under the Gemini/Subaru time exchange, and (iii) the French community under the GRACES collaboration. Multi-participant joint proposals should be submitted by the deadline of the participant country to which the Principal Investigator is affiliated. An overview of the Gemini proposal submission and time allocation process is given here.

Participant Submission Deadline
United States April 07, 2020 at 23:59 (Mountain Standard Time)animated
Canada April 07, 2020 at 16:00 (Pacific Daylight Time)animated
Brazil April 07, 2020 at 23:59 (Brazilian Time)animated
Argentina April 03, 2020 at 17:00 (Argentina Time)animated
Korea April 07, 2020 at 23:59 (Korean Time)animated
Chile April 06, 2020 at 23:59 (Chile Time)animated
U. of Hawaii April 06, 2020 at 10:00 (Hawaii-Aleutian Standard Time)animated
Subaru Community March 31, 2020 at 23:59 (Hawaii-Aleutian Standard Time)
French Community N/A

The Call is open to all participants and host institutions : Argentina, Brazil, Canada, Korea, the United States, Chile and the University of Hawaii. US time is open to all astronomers worldwide including those at non-US institutions, although in that case the proposal must explain why U.S. national facilities are needed. The distribution of time across the partners is available in the time distribution table.

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New and Notable in 2020B!

The following capabilities and announcements are notable for the 2020B semester. Please see the relevant instrument pages and subsections of the call for proposals for details.


  • Altair (facility Adaptive Optics system) is currently not working and is under repair. ALTAIR is not available for the 2020B semester.animated
  • GNIRS (1-5 micron spectrometer) is available for the all semester (updated on Apr. 02 HST).animated
  • For users of GeMS/GSAOI, we are pleased to announce that the new natural guide star unit was successfully commissioned. Much fainter guide stars can now be selected, thus increasing the sky coverage. For details see the GSAOI web page here.
  • Gemini North will not be available between August 1-20 2020 (local time), and Gemini South will not be available between September 28 - October 16 (local time) , due to engineering shutdowns.
  • CFHT has requested no exchange time for the 2020B semester, so no time available to the French community, and no additional time available to Canada or UH.
  • Proposers from the Subaru Community, who are applying for Gemini Time, should also submit their proposals via the Subaru webform by March 3, 2019 12:00 (Noon), Japan Standard Time.
  • The Gemini community is eligible to propose Hyper Suprime-Cam (HSC) "filler" programs on Subaru in 2020B. See Other Proposal Opportunities for details.
  • Starting in 2020B, Gemini is producing gender statistics to measure and monitor gender equality across the submitted and successful proposals. We kindly ask you to fill the gender field in the investigator details section of the Phase I Tool (PIT) .
  • Remember that Gemini PIT automatically adds the time for baseline calibrations to the total time requested for each target in the proposal. Please check carefully the information provided in the Phase I Submission Guidelines section below.
  • The "Bring One, Get One" Student Observer Support Program" is back for 2020B semester.

Visiting Instruments:

  • 'Alopeke and Zorro, the fast low-noise dual-channel and dual-plate-scale imagers with speckle and wide-field modes, will be available for science (subject to demand) as resident visiting instrument at Gemini North and Gemini South, respectively, in 2020B.
  • IGRINS, a high-resolution (R~45000), single-setting, near IR (1.45 - 2.5 microns) echelle spectrometer, will be available for science (subject to demand) as visiting instrument at Gemini South in 2020B.
  • MAROON-X, a high-resolution (R~80,000), optical (500 - 900nm) spectrometer, will be available for science (subject to demand) as a visiting instrument at Gemini North in 2020B.
  • POLISH-2, a high-precision polarimeter will be available for science (subject to demand) as visiting instrument at Gemini North in 2020B.

Summary of 2020B Gemini Capabilities

Gemini North

Targets are generally limited to 18 < RA hours < 13.5 and -37 < DEC degrees < +90. There are additional constraints as described in the target accessibility and instrument restrictions page.

Facility instruments offered in 2020B, in queue or classical mode, are:

Visiting instruments offered in 2020B (subject to demand) are:

  • 'Alopeke: a dual-channel fast-readout visual-wavelength camera giving simultaneous diffraction-limited images in two filters over a 2.8 arcsec field of view; as well as a wide-field mode which provides simultaneous two-color imaging in standard SDSS filters over a 60" field of view. The scheduling and length of the Alopeke visiting block(s) will be subject to community demand.

  • GRACES: a high-resolution, R~67,500, optical (0.4-1 micron) spectrometer. Scheduled blocks to be determined with CFHT (where the instrument resides), based on demand.

  • POLISH-2: the high-precision visiting polarimeter, will be available for science at Gemini North in 2020B. The instrument is open to the community via collaborative proposals with the PI. If you are interested in obtaining data in the 2020B semester with this instrument, you must contact the PI (Sloane Wiktorowicz - sloane.j.wiktorowicz at For more details of the instrument itself, consult the following publications: Wiktorowicz & Matthews 2008, PASP, 120, 1282, Wiktorowicz & Lofi 2015, ApJL, 800, L1. In 2016B, it was found that for stars brighter than B = 6 mag, precision of around 10 parts per million requires about 10 minutes of observing time. However, due to the large intrinsic telescope polarization of 0.4%, accuracy at  the 10 part per million level has not been demonstrated at the time of this call for proposals.

  • MAROON-X: a high-resolution (R~80,000), optical (500 - 900nm) radial velocity (RV) spectrometer will be available for science at Gemini North in 2020B. The instrument is open to the community for general purpose high resolution spectroscopy. Instrument throughput is 11-12% (max, comparable to GRACES) under excellent seeing conditions but currently measured to be worse than expected for median seeing (7.5% max). For details, consult the 'Throughput and Sensitivity' section of the MAROON-X page. The instrument performance goal of sub-m/s on-sky stability for precision RV measurements is currently being validated and updated performance figures will be provided on the MAROON-X page as work progresses. For this reason, for 2020B, high precision radial velocity programs should be considered shared-risk and require collaborative proposals with the PI (Jacob Bean).

  • Visiting instruments are NOT available in Classical mode.

Gemini South

Targets are generally limited to 16 < RA hours < 12 and -90° < dec < +28°. There are additional constraints as described in the target accessibility and instrument restrictions page.

Facility instruments offered in 2020B, in queue or classical mode, are:

  • GMOS South (0.36-1.03 micron imager and spectrometer):available throughout the semester. The R600 grating is available to classical programs only. The GMOS-S detector array is currently suffering from poor charge transfer efficiency on its CCD#1 . This may affect nod-and-shuffle observations and IFU observations. We are working towards resolving this problem, and updates will be posted on the GMOS South web page .

  • GSAOI (0.9-2.4 micron adaptive optics imager) with the GeMS Adaptive Optics system: Due to guide star limitations, investigators must check the availability of Guide Star constellations using the Observing Tool before submitting a proposal. The new natural guide star unit is installed and the limiting magnitudes can be found here. Observations in IQ85 are possible for programs that can use delivered images with full-width half-maximum of ~0.2 arcseconds as opposed to the ≤ 0.1 arcseconds delivered in IQ70 or IQ20 conditions. Proposals requesting IQ85 constraints are encouraged. Observations under non-photometric conditions with 0.1 mag uniform extinction are also possible under very good IQ conditions. It is expected that at least two GSAOI/GeMS blocks of ~7 nights will be scheduled the second part of the 2020B semester. The scheduling and final number of blocks will take into account the demand from the community.

Visiting instruments offered in 2020B (subject to demand) are:

  • Zorro: a dual-channel fast-readout visual-wavelength camera giving simultaneous diffraction-limited images in two filters over a 2.8 arcsec field of view; as well as a wide-field mode which provides simultaneous two-color imaging in standard SDSS filters over a 60" field of view. The scheduling and length of the Zorro visiting block(s) will be subject to community demand.

  • IGRINS, a high-resolution (R~45000), single-setting, near IR (1.45 - 2.5 microns) echelle spectrometer. The scheduling and length of the IGRINS visiting block(s) will be subject to community demand.

  • Visiting instruments are NOT available in Classical mode.

Important Dates for 2020B

The deadline for Phase I submission varies with participant (see the submission deadline Table at the top of this CfP). For successful proposals, both queue and classical, the Phase II submission deadline is 20 of July 2020animated. Check this web page for key dates and events in the proposal process.

Phase I Submission Guidelines for 2020B

Proposals for time on Gemini, and for time on Subaru via the Gemini-Subaru time exchange program, must use the Gemini Phase I Tool (PIT). Latex and Word templates are available to create a pdf attachment which includes the science and technical cases. See the PIT page for installation information and the PIT help pages for assistance. Investigators proposing for facility instruments are requested to include the output from the integration time calculators in the proposal. Investigators proposing for POLISH-2 or MAROON-X visiting instrument must use the generic "visitor" instrument option in the PIT resource list, select Gemini North, and then enter POLISH-2 or MAROON-X for the instrument name.

Note that, following the Board resolution 2016.A.2, the time for baseline partner calibrations for the Gemini facility instruments is automatically added to the total time requested for each target in the PIT. Investigators should continue to include the time associated to overheads (acquisition time, readout time, etc) in the total time estimated for each target in the PIT. The ITC output now gives overhead estimates. Alopeke and Zorro PI's should include program time for PSF standards if they need them. See the Observing Section in the PIT help pages for details.

Time Available in 2020B

The time available for each participant and host institution in 2020B is shown on the time distribution page. At Gemini North, 156 nights are expected to be available for science. At Gemini South, 157 nights are expected to be available for science.

Subaru Exchange Time

The exchange of time between the Gemini and Subaru communities will continue in 2020B. Gemini and Subaru expect to be able to exchange a minimum of 5 nights in semester 2020B. PIs from the Gemini community are encouraged to propose for observations on Subaru.

Relevant information:

  • PIs in the Gemini community who intend to use the Subaru telescope are asked to apply through the time-exchange program and not through the open use Subaru Call. Regular proposals should be submitted via the normal Gemini Phase I process.

  • Gemini community PIs can now propose for Hyper Suprime-Cam (HSC) queue observations (preferred mode of observation). In the "queue" mode, the rules are different from the classical ones. PIs have to consider that 1 night = 7 hours of on-source integration (e. g. 0.14 night = 1 hour). PIs should explicitly mention their requested on-source time in the units of hours in their proposal. The total time that will be charged to Gemini for each HSC queue mode program will include 30% of overheads. It is also possible to request HSC "classical" time. In the case of "classical", it should be noted that it takes ~30 minutes for changing filters. Subaru can accept small size programs (e.g. 2 - 3 hours) for those proposals requesting time with HSC in queue mode only. For any other instrument, Subaru time must to be requested in integer nights, however for Gemini participants with a small time share, half night allocations may be possible if a suitable program can be found for the other half night. The runs on Subaru will be evenly distributed across dark, grey and bright nights and there will be at most 5 HSC observing runs from Sep. 2020 to Jan. 2021

  • Telescope/instruments downtime: (1) At most 16 nights downtime in total for telescope system controller (TSC) upgrade work. (2) Upgrade work of top unit exchanger (TUE) controlling system will be conducted from May 29 through middle of August 2020. HSC and FOCAS cannot be used during this period because IR secondary will be mounted.

  • Please note that LGS-AO is not available in 2020B because of laser upgrade work.

Facility instruments offered in 2020B:

Visiting instruments offered in 2020B (limited to one or two runs):

  • CHARIS: Coronagraphic High Angular Resolution Imaging Spectrograph - provides high contrast images of exoplanets, disks, brown dwarfs with SCExAO.

  • SCExAO: Subaru Coronagraphic Extreme Adaptive Optics - delivers high contrast images of the innermost surrounding of bright sources to CHARIS. The VAMPIRES module in SCExAO is also available for science observations in 2020B.

  • IRD - Infrared Doppler: infrared high-dispersion, high resolution (up to 70,000) fiber-fed spectrometer. IRD provides high spectral resolution echelle spectroscopy and radial velocity measurements from 0.97 to 1.75 um simultaneously combined with AO188. IRD is available only in shared-risk. IRD SSP is started in 2019A – any IRD proposal must clarify how its scientific aim is different from SSP. A new observing mode, REACH (SCExAO+IRD), is available.

  • Observing proposals using the visiting instruments must include the relevant instrument PIs as a Co-investigators.

Priority Visitor Observing Mode

In Priority Visitor Observing, a visiting observer comes to the Observatory for a block exceeding their program's time allocation, and elects when to carry out their program within that block. This may be when conditions are within their requirement, better than their requirement or even fail to meet their requirement. If time remains on the program after the observing time is complete, the program carries on in the regular queue with priority given by the TAC-assigned science ranking band. When not executing their own program the visiting observer will execute other Gemini queue observations. PV observing mode is offered as a possibility for band 1 queue programs in 2020B. Investigators wishing to have their program considered for PV observing should indicate their desire to participate in the Technical Design portion of their 2020B queue proposal.

Other Proposal Opportunities in 2020B

Other proposal opportunities are available at Gemini Observatory in 2020B. These include:

  • Large And Long Programs (LLPs) are Principal Investigator-defined and -driven programs that are expected to require either significantly more time than a partner typically approves for a single program, or extends over two to six semesters, or both. Up to 20% of the available time from participating parters (US and Canada) is available for LLPs. LLP proposals are currently being accepted from PIs based at an institution of one of the participating partner countries and who have submitted a letter of intent by the appropriate deadline. The 2020B LLPs proposal submission deadline is April 7, 2020 at 23:59 (Hawaii-Aleutian Standard Time). animated Further information on LLPs and the LLP proposal process can be found on the Large And Long Programs page. Information on previously accepted LLPs and their science programs is available here.

  • The Fast Turnaround (FT) Program provides monthly opportunities to submit proposals, with successful programs scheduled for observation starting one month after each proposal deadline. Up to 10% of the time at Gemini North and Gemini South is available for the FT programs.

  • Poor Weather Proposals are solicited for programs that can use poor, but usable, conditions and are executed when nothing in the regular queue is observable. Proposals can be submitted via the normal TAC process (this call) or at any time.

  • For Semester 2020B, the Gemini community is also eligible to propose HyperSuprimeCam (HSC) filler programs on Subaru. Filler programs are executed in poor observing conditions (typically seeing >1.5 arcseconds, and/or poor transparency), up to 35 hours can be requested by a filler proposal. Execution is not guaranteed: observations are made only when there is no other program in the HSC queue. In recent semesters, typically of order 15% of HSC time has gone to filler programs. Applications may be submitted once per semester, the next deadline for filler proposals is April 7, 2020 3:00 am (UT). Proposals must be sent through the Subaru submission system (NOT Gemini), and are considered only by the Subaru TAC. Note that only a short text summary of the program is required, not a full detailed Science Justification.

Bring One, Get One: Travel Assistance Program

The Gemini Observatory, at the request of its Users' Committee, would like to encourage visits by students and other early-career observers to observing runs (attending Queue, Classical, or Priority Visiting Observing). In semester 2020B, the Gemini Observatory may subsidize with up to US$2000 the travel expenses of individual undergraduate and grad students, and other early career observers, visiting Gemini North or South, when accompanying a senior observer. The "Bring One, Get One" Student Observer Support Program" page provides details on this program, which is subject to the availability of funds.

Remote Eavesdropping

Remote Eavesdropping will be available in 2020B for all queue programs. Investigators will be invited to sign up for eavesdropping via the PI email announcing they have been granted time.

Data Rights, Proprietary periods and Data Distribution

All data taken with the Gemini telescopes are the property of the Gemini Observatory. Principal investigators of Gemini regular programs (Queue/Classical/Poor Weather) have exclusive access to the data for their program for a period of 12 months. After the proprietary period the data are publicly available. See the page Data Rights and Proprietary Periods for more information.

All data, including raw and available processed data, obtained with the Gemini telescope are distributed exclusively through the Gemini Observatory Archive. More information about the data distribution is given here.

Supporting information to the Call for Proposals

Relevant general information related to the applications for time on Gemini Telescopes is presented in the supporting information page. Consult there for the following:

  • Time Allocation Process (National and International Time Allocation Committees)
  • Submitting for time on both telescopes
  • Band 1 Persistence
  • Electronic PIT Submission
  • Joint Proposals
  • Under-utilized Instruments
  • Rapid Response or Target of Opportunity
  • GMOS Mask definitions
  • Poor Weather Programs
  • Exchange Time
  • Target information (guide stars, non-sidereal objects, time-specific observations)
  • Duplicate Observations

Prospective users should also refer to the target and instrument accessibility page, and the instrument pages for detailed and up to date information on instrumentation.

Questions and Answers

All questions concerning proposals, or any other subject, should be made using the Gemini HelpDesk. This web-based system will send the request to your National Gemini Office staff in the first instance who will escalate it to Gemini staff if necessary.

Comments and suggestions on the format and content of this page and supporting pages are welcome, and should be sent to Marie Lemoine-Busserolle.

Gemini Observatory Participants