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2013B Instrument Availability and Target Accessibility

This page provides best estimates, at the time of the Call for Proposals, of instrument availability and target (RA, dec) restrictions for 2013B. Jump to:


Instrument and Instrument Configuration Restrictions

At each Gemini telescope, instruments are mounted at the Cassegrain focus on the instrument support structure (ISS). A science fold mirror mounted inside the ISS can be rotated to send the light from the telescope to any of four side-looking ports, or can be retracted so that the light goes to the up-looking port. At each site, the calibration unit and the Adaptive Optics system use two of the side ports, leaving two side-looking and one uplooking port for other instrumentation. As more than three instruments are offered each semester, instrument swaps will be required and not all instruments will be available for the entire semester. Instrument swaps will be driven by demand and scheduled to minimize impact on the queue. Certain targets or entire programs may not be feasible once the final schedule is determined, at ITAC or thereafter. Changes to the instrument mounting are not permitted during classical runs.

If an instrument is requested for less than 6% of the Bands 1+2 time, the Observatory reserves the right to limit the RA range available to programs, or to not schedule the instrument. Similarly, the Observatory may choose to limit available configurations, such as the little used R600 grating in GMOS. Investigators applying for low-demand configurations should indicate if the science can be achieved with an alternate configuration.



Non-Sidereal Targets

Non-sidereal targets can have a broader range in RA than indicated in the Tables below due to, for example, the need to observe comets relatively close to the Sun. The ephemeris for any submitted target however must include a position that is accessible between evening and morning twilight at some point in the semester. For rapidly moving targets PIs should specify in the proposal when the target is accessible, and the coordinates of the target at that time, so that the observation can be checked for feasibility.



Gemini Frontier Fields Observations

During 2013B, some of the Gemini Director's Discretionary Time will be allocated to use GSAOI and GeMS to observe two galaxy clusters that are part of the Hubble Space Telescope Frontier Fields program. We will obtain images of Abell 2744 and MACSJ0416.1-2403 in the K(short) filter. We plan to obtain approximately 5 hours on-source of each field, reaching an estimated (point-source) sensitivity of 26.3 AB magnitudes (24.4 Vega). The available guide stars constrain the pointings, which will be centered on RA=00:14:18.9, DEC=-30:22:38.1 (Abell 2744) and RA=04:16:06.9, DEC=-24:05:38.1 (MACSJ0416.1-2403) and cover the GSAOI 85 arcsecond field of view. These data will be immediately accessible in the Gemini Science Archive with no proprietary period, and we will also produce reduced images for the community after the observations are complete. We are providing this information now to avoid duplication of proposers' effort. Investigators who require deeper or different but related observations should not hesitate to propose for them.



Gemini North Instrument Availability and Target Accessibility

All instruments are restricted for sky visibility as described in the Table and Figure below. In addition:

  • GNIRS will return to the telescope in mid-August following a lens replacement; targets are therefore limited to RA 18h to 13.5h.
  • Depending on demand, we expect to offer the visitor instruments
    • the DSSI Speckle camera during July and August bright time, limiting RAs to 15.5h to 3h.
    • TEXES during October bright time, limiting RAs to 20h to 7.5h.
  • The Laser Guide Star (LGS) system must be used at or above 40 degrees elevation. How this translates into RA and dec restrictions is indicated in the Table.
  • Michelle has been retired and is not offered in 2013B.


Accessible Restricted** Inaccessible
Declination,
non-LGS
-30d to +73d -37d to -30d,
+73d to +90d
< -37d
Declination,
LGS
-22d to +65d -27d to -22d,
+65d to +68d
< -27d and > +68d
Right Ascension,
non-LGS
19h to 11h 17h to 19h,
11h to 13.5h
13.5h to 17h
Right Ascension,
LGS
20h to 10h 18h to 20h,
10h to 12.5h
12.5h to 18h
Right Ascension,
GNIRS
19.5h to 11h 18h to 19.5h,
11h to 13.5h
13.5h to 18h
Right Ascension,
DSSI Speckle
16.5h to 2h 15.5h to 16.5h,
2h to 3h
3h to 15.5h
Right Ascension,
TEXES
21h to 6.5h 20h to 21h,
6.5h to 7.5h
7.5h to 20h

**Due to limited sky availability during the semester, GMOS MOS programs requiring pre-imaging should not have targets in this region, and other programs with targets in this region should not require a large amount of time, or have strict timing or observing constraints.



Gemini South Instrument Availability and Target Accessibility

All instruments are restricted for sky visibility as described in the Table and Figure below. In addition:

  • FLAMINGOS-2 will be available throughout the semester on a shared-risk basis, in imaging and long-slit modes only. Targets with RAs 23h to 6h are particularly encouraged, to cover the period October to November when GMOS-South may be unavailable.
  • GMOS may not be available during October and November while the CCDs are upgraded and other maintenance work is performed. The amount of time at RA 23h to 6h will therefore be limited, and investigators should indicate in the technical case of their proposal if alternate targets are available.
  • GSAOI + GeMS is expected to be available between September and January, limiting RAs to 19h to 11h. Observations using GeMS are restricted to greater than 45 degrees elevation. How this translates into RA and dec restrictions is indicated in the Table.
  • Neither NICI or T-ReCS are offered in 2013B.


Accessible Restricted** Inaccessible
Declination -87d to +22d -90d to -87d,
+22d to +28d
> +28d
Declination,
GSAOI + GeMS
-70d to +10d -75d to -70d,
+10d to +15d
< -75d and > +15d
Right Ascension 19h to 9h 16h to 19h,
9h to 12h
12h to 16h
Right Ascension,
GSAOI + GeMS
21h to 8h 19h to 21h,
8 to 11
11h to 19h

**Due to limited sky availability during the semester, GMOS MOS programs requiring pre-imaging should not have targets in this region, and other programs with targets in this region should not require a large amount of time, or have strict timing or observing constraints.



Graphical Illustration

GN Target Accessibility

Figure 1: Schematic representation of target accessibility at Gemini North during semester 2013B. Green regions offer unrestricted access, red regions are inaccessible. Hatched areas indicate the more restricted LGS regions. The yellow region is possible, but restricted. See text, and values in the Gemini North Table above.

GS Target Accessibility

Figure 2: Schematic representation of target accessibility at Gemini South during semester 2013B. Green regions offer unrestricted access, red regions are inaccessible. Hatched areas indicate the more restricted GeMS regions (note that the limited availability of GSAOI in 13B further restricts the GSAOI + GeMS combination). The yellow region is possible, but restricted. See text, and values in the Gemini South Table above.