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  • Phase I - Proposal for telescope time and time allocation
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2023A Call for Proposals

Updated June 11, 2024 by pablo.martin
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Gemini Observatory invites its community to propose scientific investigations for the 2023A semester, 1 February 2023 - 31 July 2023.

The table below shows submission deadlines for all Gemini Participants, and the Subaru community under the Gemini/Subaru time exchange. Multi-participant joint proposals should be submitted by the deadline of the participant country to which the Principal Investigator is affiliated. For more on the Gemini proposal submission and time allocation process, please consult the Phase I page.

Participant Submission Deadline
United States Friday September 30, 2022 at 23:59 (Mountain Standard Time)
Canada Friday September 30, 2022 at 16:00 (Pacific Daylight Time)
Brazil Monday October 3, 2022 at 23:59 (Brazilian Time)
Argentina Friday September 30, 2022 at 17:00 (Argentina Time)
Korea Monday October 3, 2022 at 23:59 (Korea Standard Time)
Chile Friday September 30, 2022 at 23:59 (Civil Chile Time)
Univ. of Hawaii Monday October 3, 2022 at 10:00 (Hawaii-Aleutian Standard Time)
Subaru Community Friday September 30, 2022 at 23:59 (Hawaii-Aleutian Standard Time)

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.  In 23A time is also available to the French community as compensatory time for the use of GRACES via ESPaDOnS; the deadline for French PIs is Saturday October 1 at 23:59 (Hawaii-Aleutian Standard Time).


Time Available in 2023A

A summary of the time distribution at each telescope is shown in the Table below. More information is available at the time distribution page. At Gemini North, 171 nights are expected to be available for science. At Gemini South, 152 nights are expected to be available for science.

Participant/Type  North hours  South hours Notes Participant/Type  North hours  South hours Notes
US 689 556 US open skies policy allows PIs from any country to apply. Limited Term Partner 2 2 Currently: Ben-Gurion University 
Canada 199 161 Includes GRACES compensatory time. Director's Discretionary 76 61 Open to any astronomer.
Argentina 26 21 Fast Turnaround 152 113 Open to PIs from US, CA, AR, BR, KR, UH (North only). Not open to CL.
Brazil 80 66 Large and Long 185 154 Pre-allocated for 23A.
Korea 90 72 France 9 9 GRACES compensatory time.
Univ. of Hawaii (host) 167 Includes GRACES compensatory time. Guaranteed Time 38 173 For the MAROON-X, IGRINS, FLAMINGOS-2, and GHOST instrument teams
Chile (host) 132 Engineering 94 284 Maintenance, Gemini Program Platform testing, vibration tests at Gemini North, primary mirror recoat at Gemini South.


New and Notable in 2023A

The following capabilities and announcements are notable for the 2023A semester. Please see the relevant instrument pages and subsections of the call for proposals for details.

General:

  • All Gemini proposals requesting time from the US, CA, BR, or AR must be anonymized. Proposals which do not meet the guidelines will be penalised. This applies to proposals requesting time only from these partners, as well as joint proposals requesting time from multiple participants which include any of these partners. This requirement applies whether it is the PI or a co-I that has the relevant partner affiliation.

  • All proposals to use Gemini in 2023A must use the Phase 1 template, which was revised in 22B to enable anonymous reviews, and to make proposals requirements, such as page and figure limits, uniform across the partners. Two attachments are required for the proposal so that team information can be separated from the science case.

  • Starting in 22B, the Gemini Phase 1 Tool includes an option to specify that the Gemini proposal is part of the AEON multi-telescope-facility system, and an option to identify proposals which have synergies with James Webb Space Telescope observations, whether already awarded, or still to be proposed.

  • Classical mode observing is NOT offered in semester 2023A. Priority Visitor mode is offered at both Gemini North and Gemini South; however if circumstances preclude having people on site, then awarded Priority Visitor time will revert to queue. The "Bring One, Get One" Student Observer Support Program remains unavailable.

Facility Instruments:

  • NEW for 2023A - GMOS South is now available with a B480 grating. This grating is not yet installed in GMOS North.

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 as resident visiting instruments at Gemini North and Gemini South, respectively, in 2023A.
  • IGRINS, a high-resolution (R~45000), single-setting, near IR (1.45 - 2.5 microns) echelle spectrometer, will be available for science as a visiting instrument at Gemini South in 2023A. See the IGRINS at Gemini page for information on how to determine exposure times.
  • MAROON-X, a high-resolution (R~80,000), optical (500 - 900nm) radial velocity (RV) spectrometer, will be available for science  as a visiting instrument at Gemini North in 2023A. The instrument is open to the community for high precision RV studies as well as general purpose high resolution spectroscopy. The instrument has demonstrated sub-m/s on-sky precision for RV measurements of M dwarfs, although the instrument performance is continually being assessed and improved. Please use the Maroon-X Exposure Time Calculator to evaluate the instrument performance.


Summary of 2023A Gemini Capabilities

Gemini North

Targets are generally limited to 4 < RA hours < 1 and -37 < DEC degrees < +90. There are additional constraints as described in the target accessibility and instrument restrictions page.

Facility instruments offered in 2023A are:

  • GMOS North (0.36-1.03 micron imager and spectrometer): available throughout the semester. The R600 grating is not available.

  • GNIRS (1-5 micron spectrometer): As before, the short red camera is NOT available. YJHK imaging is available via the acquisition keyhole. A new low-resolution IFUs is being commissioned and will be offered for Fast Turnaround proposals only in semester 2023A.

  • NIFS (0.95-2.40 micron integral field unit spectrometer): available with or without AO capability. This instrument shares a port with NIRI and MAROON-X, hence it will only be available during specific blocks. NIFS is expected to be scheduled for two or three approximately one-month-long blocks during the semester. If the GNIRS IFUs are successfully commissioned in 2022, semester 2023A may be the last A semester where NIFS is offered.

  • NIRI (1-5 micron imager): available throughout the semester. As in past semesters, NIRI is NOT available for spectroscopy. This instrument shares a port with NIFS and MAROON-X, hence it will only be available during specific blocks. NIRI  is expected to be scheduled for two or three approximately one-month-long blocks during the semester.

Visiting instruments offered in 2023A 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.  Targets of Opportunity (Rapid or Standard) are accepted for Alopeke, but will only be executed during the instrument blocks.
  • 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. Semester 2023A may be the last semester where GRACES is offered.
  • MAROON-X: a high-resolution (R~80,000), optical (500 - 900nm) radial velocity (RV) spectrometer,  is open to the community for high precision RV studies as well as general purpose high-resolution spectroscopy.  Please use the Maroon-X Exposure Time Calculator to evaluate the instrument performance. This instrument shares a port with NIFS and NIRI, hence it will only be available during specific blocks. MAROON-X is expected to be scheduled for two or three approximately one-month-long blocks during the semester.
  • Not offered in 23A: TEXES, POLISH-2.

Gemini South

Targets are generally limited to 5 < RA hours < 1 and -90° < dec < +28°. It is planned to execute the delayed primary mirror coating at Gemini South during the last three weeks of April, 2023. This date is a placeholder, and may change based on the progress of the coating preparations. If an April shutdown occurs, the time available at RAs 9 - 11 will be reduced by about 20%. There are additional constraints as described in the target accessibility and instrument restrictions page.

Facility instruments offered in 2023A are:

  • GMOS South (0.36-1.03 micron imager and spectrometer): The noise problem on CCD-2 persists, as of August 2022; users are advised to dither or to place targets or spectral features on other parts of the detector. GMOS South may be removed for extensive engineering in the April to May 2023 period, to address this issue. In that case the instrument will not be available, and there will be reduced access to GMOS targets in the RA range of 8 to 12. Prospective users should check the instrument page for updates. The R600 grating is not available, however the new B480 grating is available, in 23A.

  • FLAMINGOS-2 (0.9-2.4 micron wide-field imager and spectrometer): offered in imaging, long-slit and MOS modes throughout the semester. The multi-object spectroscopy (MOS) mode allows simultaneous observation of up to 150 targets per mask over an area of 6'x2'.

  • 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.  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. Observations under non-photometric conditions with 0.1 mag uniform extinction are also possible under very good IQ conditions.  The expectation is to have two or three laser runs of 7 nights each during the semester, the actual schedule will be based on the demand from the community.

Visiting instruments offered in 2023A 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.  Targets of Opportunity (Rapid or Standard) are accepted for Zorro, but will only be executed during the instrument blocks.

  • IGRINS, a high-resolution (R~45000), single-setting, near IR (1.45 - 2.5 microns) echelle spectrometer, will be available throughout the semester except for two weeks before and during the 7-night GeMS/GSAOI runs. See the IGRINS at Gemini page for important information about writing IGRINS proposals.


Important Dates for 2023A

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 18th January 2023. Check the 2023A schedule for key dates and events in the proposal process.


Phase I Submission Guidelines for 2023A

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 pdf attachments which include the science and technical cases, and investigator information. The template has been revised to enable the anonymous review process, and to make proposals requirements uniform across the partners. Two attachments are required for the proposal so that team information can be separated from the science case.

All Gemini proposals requesting time from the US, CA, BR, or AR must be anonymized. Proposals which do not meet the guidelines will be penalised. This applies to proposals requesting time only from these partners, as well as joint proposals requesting time from multiple participants which include any of these partners. This requirement applies whether it is the PI or a co-I that has the relevant partner affiliation.

Investigators from the French community, requesting Gemini time via the CFHT GRACES compensatory time, must use the Gemini Phase I Tool (PIT). On the "Time Requests" tab of the PIT, select "Proposal Class: Queue Observing'', and "Request Type: Exchange Request (CFH PIs)".

Additional options in the Time Requests module in the PIT were added in 2022B:

  • the option to specify that the proposal is for the AEON multi-telescope-facility system. 
  • the option to identify proposals which have synergies with James Webb Space Telescope science. The goal for providing this proposal category is to encourage development of science programs that benefit from a combination of Gemini and JWST observations.  More information is available here.

Time for baseline partner calibrations 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 PIs should include program time for PSF standards if they need them. See the IGRINS at Gemini page for information on how to determine exposure times for that instrument.  PIs with targets that can be observed from either Gemini North or South (e.g. equatorial targets to be observed with one of the GMOS instruments) can request time with both instruments, in that case the time with each instrument should be halved, and the Observatory will update the observation times when targets are scheduled.

Targets of opportunity proposals must include all instrument configurations which the team may want to use, at Phase 1. This enables automatic creation of templates, and avoids errors at Phase 2.


Subaru Exchange Time 

The exchange of time between the Gemini and Subaru communities will continue in 2023A; around 5 nights are expected to be available on Subaru for the Gemini community via the exchange program. A summary of the Subaru capabilities in 2023A is given below, PIs should also consult the Subaru Call for Proposals.

In addition, the Gemini community can propose shorter programs for Subaru's Service mode. PIs must indicate on the proposal whether regular or service time is requested. Service programs must be short programs of less than 4 hours duration including calibration and overheads, using one of FOCAS, IRCS(+AO), HDS, MOIRCS (imaging). Around 1 night is expected to be available in this mode for the Gemini community. Prospective investigators must carefully review the Service Program web page. In particular, some additional, detailed technical information must be provided at the time of Phase-1 submission. Service proposals are reviewed by the National TACs together with the regular proposals.

Relevant information:

  • Do NOT double-dip! PIs applying for time on the Subaru telescope must only apply via ONE of the following routes: Japanese researchers via the Subaru call; other researchers via the open use time offered in the Subaru call; Gemini community PIs via the Gemini time-exchange program; or Keck community PIs via the Keck time-exchange program. Duplicating your proposal across more than one of these committees will disqualify the proposal.
  • Proposal submission: Proposals for time on Subaru via the Gemini time-exchange program are submitted via the normal Gemini Phase I process.
  • Instrument switches during the night: Switching between IRD, REACH, CHARIS, VAMPIRES, Fast PDI, and MEC during a single or half-night observation is possible. Please check the Subaru Call for Proposals for the time required for switching instruments.
  • Subaru telescope downtime: the telescope will not be available for 1 to 3 days due to maintenance work on the electrical system. The dates will be announced later.

Facility instruments offered in 2023A:

  • AO188 (Subaru 188-elements Adaptive Optics system) is available in Natural Guide Star mode and Laser Guide Star mode.

  • FOCAS (optical camera and spectrograph) is available. 

  • HDS (optical high dispersion spectrometer) is available.

  • Hyper Suprime-Cam (HSC - very wide field optical to far-red imager) will have a maximum of four observing runs between March and June. Some filters require permission for use, prospective users should check the HSC web page. Important notice for HSC filters: all applicants must explicitly describe the filters they intend to use, in their proposal. The desired set as well as the minimum acceptable set should be clearly specified.

  • MOIRCS (Multi-Object Infrared Camera and Spectrograph) back online in shared-risk mode.

  • IRCS (infrared camera and spectrometer, with Natural and Laser Guide Star Adaptive Optics capability) is available. The polarimetry mode is a shared-risk mode.  PIs should check the filter availability for the instrument before submitting a proposal.

Visiting instruments offered in 2023A, are listed below. Proposals to use visiting instruments must include the instrument PIs as Co-investigators. 

  • CHARIS: Coronagraphic High Angular Resolution Imaging Spectrograph, including spectro-polarimetric mode - with SCExAO.
  • Fast PDI (in shared-risk mode): polarization differential imaging (PDI) with a high speed (>kHz) near-IR (950 - 1860 nm) low-noise camera (C-RED One), optimized for high contrast imaging of circumstellar disks with SCExAO+AO188. 
  • IRD - Infrared Doppler (in shared-risk mode): infrared high-dispersion, high resolution (up to 70,000) fiber-fed spectrometer.  IRD SSP is started in 2019A – any IRD proposal must clarify how its scientific aim is different from SSP. The observing mode REACH (SCExAO+IRD), is available.
  • MEC (in shared-risk mode): the MKID Exoplanet Camera is a near-IR (800-1400nm) photon-counting low-resolution (R~5) integral field spectrograph optimized for high contrast imaging with SCExAO+AO188.
  • VAMPIRES : The Visible Aperture Masking Polarimetric Imager for Resolved Exoplanetary Structures (VAMPIRES) is a visible light instrument on the SCExAO system. 
  • NsIR Wave Plate Unit: a visiting device for IRCS/SCExAO polarimetry mode.


Other Proposal Opportunities in 2023A

Other proposal opportunities are available at Gemini Observatory in 2023A. These include:

  • 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. PIs must be members of the Argentina, Brazil, Canada, Korea, University of Hawaii or United States astronomy communities. Chile has withdrawn from the FT program and therefore Chilean PIs do not have access to FT time.

  • Director's Discretionary Time is open to any astronomer worldwide and proposals can be submitted at any time.

  • 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. PIs must be based in Gemini participating countries or the host institutions.
  • The Gemini community is 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), and up to 50 hours can be requested by a filler proposal, although the first 4 hours have priority. Execution is not guaranteed: observations are made only when there is no other program in the HSC queue.  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.


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. Data acquired as part of a Director's Discretionary (DD) program have a standard proprietary period of 6 months, however in exceptional circumstances the Observatory may remove DD proprietary periods. 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
  • Targets 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. The 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 Sandy Leggett.


International Gemini Observatory

The International Gemini Observatory  provides the astronomical communities in six participant countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country's contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Agencia Nacional de Investigación y Desarrollo (ANID), the Brazilian Ministério da Ciência, Tecnologia e Inovação, the Argentinean Ministerio de Ciencia, Tecnología e Innovación, and the Korea Astronomy and Space Institute (KASI). The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.     


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