Call for Proposals

Semester S21B: August 1, 2021 -- January 31, 2022

Subaru Telescope, National Astronomical Observatory of Japan

Subaru Telescope invites observing proposals for Semester S21B. Since each instrument has its own specific restrictions/conditions, applicants are required to consult the relevant instrument page when preparing their proposals. Please also refer to Proposals, How to Submit via webform, Open Use Policy and Telescope webpage.

Open Use Schedule for S21B

Deadline of Normal/Intensive Program Submission March 9 (Tue), 2021 12:00 (Noon) in Japan Standard Time (i.e., March 9, 3:00 am in UT)
Deadline of Service/Filler Program Submission April 6 (Tue), 2021 12:00 (Noon) in Japan Standard Time (i.e., April 6, 3:00 am in UT)
Time Allocation Committee late April
Notification of selection results early June


Webform the ProMS 2.0 page Instructions How to Submit via webform?

Other instructions

Instructions Open Use Policy, and each instrument page

Important Notice for S21B

Telescope Downtime and Restrictions The actual start of S21B will be in the middle of August due to the downtime for the UPS replacement work. Another consective ten weekdays downtime, mostly in bright nights, are expected for the installation of PFS.
Also, the overhaul work of the top unit exchanger that was postponed from S21A due to the COVID-19 spread shall be done in S21B and the HSC will not be available for about two and half months while the work is in progess. The detailed schedule of the work hasn't been fixed yet.
Changes in HSC Queue Application Requested telescope time for HSC queue observation (except for filler program) should be "multiple" of 1 hour which is equivalent to 0.1 night according to the observatory's policy of 10 hours per night. The requested time must include various overheads, which can be calculated using HSC overhead and required time calculator.
Only NGS Mode Proposals for AO188 Our laser system is currently under the upgrading process. Proposals that can be accomplished only with NGS mode are acceptable for AO188 in S21B. Please check the AO188 webpage for the latest information.
IRCS unavailable in August and September IRCS will be unavailable in August and September due to replacement work of the cold head.
Status of Visiting Instruments/devices (PI Instrument/devices) Following instruments/module are offered for openuse in S21B:
- CHARIS with SCExAO+AO188 (including spectro-polarimetric mode)
- Fast PDI (in a shared-risk mode)
- IRD (in a shared-risk mode)
- MEC (in a shared-risk mode)
- REACH (combination of SCExAO and IRD for single-mode fiber spectroscopy)
- SWIMS (in a shared-risk mode)
- NsIR Wave Plate Unit (a visiting device for IRCS/SCExAO polarimetry mode)
Proposals to use visiting instruments must include the instrument PIs as Co-investigators. Visiting instruments may be used in intensive programs if necessary conditions are fulfilled. Please check the Intensive webpage.
Notice on New Visiting Instruments: MEC and Fast PDI MEC and Fast PDI are planned to be opened from S21B and accept proposals. The final decision on their openings will be made in the middle of April 2021.
SWIMS Operation in S21B SWIMS is opened from S21A to S22B as a substitute for MOIRCS, and MOIRCS is in a hibernate state. SWIMS applicants can NOT request MOIRCS as a backup instrument.
Instrument Switching between IRD, REACH, CHARIS, VAMPIRES, Fast PDI, and MEC Instrument switching between IRD, REACH, CHARIS, VAMPIRES, Fast PDI, and MEC in one or half observation night for one observing proposal is possible. The required time for switching is,
- REACH <=> VAMPIRES: 0 (REACH can be used with VAMPIRES simultaneously)
- IRD <=> REACH: ~20 minutes (if the laser frequency comb is required for both IRD and REACH, otherwise 5 minutes)
- Other combination: <5 minutes
Note that IRD <=> REACH switching with laser frequency comb for both IRD and REACH is allowed up to twice per one night per one observing proposal.
Intensive Proposals using Gemini Instruments Intensive proposals using Gemini instruments can be submitted only for B semesters (only March deadline). If you want to start your Gemini Large/Long Program (LLP) or intensive program using Gemini instruments in S22A, you need to apply this time.
Observation w/o the Windscreen The windscreen of the Subaru telescope is continuously out of operation in S21B, and thus tracking accuracy of the telescope may be degraded by high winds. Since observations may be interrupted by high winds, it is recommended to prepare backup targets with different azimuth angles.

Reminder About Basic Rules

Moon-affected Unacceptable Dates If the Moon is close to the target, the observation could be severely affected by the Moon light and such condition should be avoided. Applicants are responsible to avoid such condition to occur by specifying the inconvenient/unacceptable dates in Hawaii Standard Time. Those inconvenient or unacceptable dates should be explicitly indicated in Entry 13 (Scheduling Requirements).
2nd Choice Instruments If your science goal could (fully or partly) be achieved by other instruments (of Subaru/Keck/Gemini) instead of your 1st choice instrument, we recommend you to describe such alternative instruments, which may be usable/acceptable to achieve your science goal, as 2nd choice instrument(s). If you choose a PI-Type instrument as a 2nd choice instrument, you need to get approval from the PI of PI-Type instrument.
Duplicated Submission Unallowable An identical proposal of the same science and targets using the same instrument and telescope should not be submitted at the same time through different TAC processes. For example, if a proposal using Keck or Gemini was once submitted to Subaru time-exchange program, it should not be applied to the ordinary proposal selection on Keck or Gemini side at the same semester (and vice versa).

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updated on February 8, 2021