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PATT Call for Proposals for Semester 2011B 1500 GMT 22 February 2011

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The Liverpool Telescope Time Allocation Committee is now accepting proposals for PATT time for observations in Semester 2011B (1st August 2011 to 31st January 2012). You may also apply for Reactive Time at any point as described at the end of this call.

Time available and deadline

The deadline for submission is 31st March 2011. The total available time for PATT users in 2011B excluding pre-allocated time is around 282 hours. This is a considerable increase on previous B-semester availability due to significant increases in operational efficiency. Time is allocated approximately in ratio 2:1 between Priority A and B. Applications are particularly encouraged for spectroscopic and good time, which are typically less subscribed than average time.

Instrument availability

The instruments available are FRODOSpec, RATCam, RINGO2 and RISE.

  • FRODOSpec is the multi-purpose integral-field input spectrograph. Its specification allows observations at 380-1000 nm in either low (~2400) or high (~5400) resolution mode. The IFU provides a 12x12 lenslet array over a total field of view of ~10 arcsec. Blue arm throughput was improved by a factor of 3 during 2010.
  • RATCam is an optical CCD camera with a 4.6 4.6 arcmin field of view. The available filters are Sloan u’, g’, r’, i’, z’, Bessell B and V, and Hα. Observations can also be obtained without filters.
  • The RINGO2 polarimeter offers significant improvements on RINGO, with a sensitivity improvement of 2 magnitudes and much simpler data reduction.
  • RISE is a fast-readout camera developed in collaboration with Queens University Belfast. It has a fixed "V+R" filter (similar to that used in RINGO) and reimaging optics giving a 7x7 arcmin field of view. An e2V frame transfer detector is used to obtain a cycle time of less than 1 second. For exoplanet proposals you must contact the telescope director Iain Steele or instrument PI Don Pollacco before submitting your proposal

Note that all instruments are now designated common user, but potential users are welcome to contact Phase 1 support, at phase1@astro.livjm.ac.uk, to discuss the capability of the instrument and feasibility of the observing programme well before submitting an observing proposal.


The telescope routinely observes standard stars with RATCAM and RISE only. These standards will be taken in u, B,V,r,i and z (i.e. g and H alpha standards will NOT be taken). NO standards will be taken for RINGO or FRODOSpec). Observers who wish to obtain standards, apart from those that are routinely observed, will need to include observations of these standards in their own programmes. Information on all these instruments is available HERE.

Proposal process

Applications are submitted in two phases:

Phase 1 – the science definition phase

Phase 1 proposals are sent to the Telescope Allocation Committee (TAC) outlining the science case for observation and, in particular, why they are suitable for a robotic telescope.

  • See HERE for instructions on how to prepare and submit your Phase 1 proposal.
  • Please note the requirement to specify a Minimum Usable Fraction (MUF); see below.
  • Please note the guidance on Maximum Group Length (available HERE), but users with a particularly strong case should not be put off by this constraint.

Phase 2 – the observation specification phase

Once proposals have been approved by the TAC, users can enter observation requests using the Phase 2 User Interface, an online Java tool to program observation instructions and transmit them directly to the telescope. (See HERE for extensive online help). The LT Support Astronomer is also available to assist with phase 2 submission.

Priority Definition

Successful proposals are entered into the observing queue with one of three rankings:
AHigh priority programmes. The TAC would like to see 100% completion of the observations.
BMedium priority programmes. The TAC would like to see at least the MUF of observations obtained, provided this does not impact on the completion of priority A programmes.
CLow priority programmes. These programmes are used to over-subscribe the observing queue so that the telescope is not idle. There is no guarantee that any observations will be obtained. If observations are started for a programme then the scheduling software should aim to obtain at least the MUF of the observations, but not at the expense of 100% completion of priority A or B programmes. There will be approximately an additional 105 hours available for priority C programmes in semester 2011A, spread across all observing conditions.

Minimum Usable Fraction

The MUF (Minimum Usable Fraction) was introduced by the PATT TAC to help the LT technical team schedule observations effectively, e.g., to decide whether to finish the observations for one programme or to start a new programme that may not be completed. Please specify the MUF for your programme in the technical case of the Phase 1 proposal. For example, the MUF can be used to specify that “any observations would be usable” (MUF=1%), or “a complete or nearly complete sample is essential to achieve the science goals” (MUF=90%). The TAC may revise the MUF of successful proposals if they feel this is appropriate.

Telescope performance

The current rms pointing of the LT is 6 arcsec. The current tracking performance provides seeing-limited images (FWHM < 0.8 arcsec) for exposures up to 1 minute without the auto-guider (open loop) and up to 30 minutes with the auto-guider (closed loop). Individual exposures with the auto-guider are limited to 30 minutes.

Observing conditions

We welcome applications for all available observing modes, conditions and RA ranges, particularly those that take advantage of the robotic or autonomous nature of the LT. The PATT time available is divided so that there is twice as much average time as good or spectroscopic time – to reflect the typical distribution of conditions in time such that half the period is in average conditions. Despite this, average time tends to be the most over-subscribed. There is much less competition for observations that can be done in good and/or spectroscopic conditions.

Reactive time proposals

Separate to the PATT twice-annual process, observers may also apply for Reactive time, typically no more than 3 hours, via:


This is open to all users, regardless of their prior use of the LT or any time they may already have allocated. It is intended to allow completion of the science goals of existing programmes (with the LT or other telescope) especially where they enable completion of a publication, to allow observations of unforeseen phenomena as targets-of-opportunity, or to enable test observations prior to a full proposal. It is not to be used to apply for time denied in the normal round or for target-of-opportunity observations of known phenomena (e.g. novae, GRBs).

The TAC aims to make a decision within 48 hours, and will generally respond more rapidly. For 2011A we set aside 12 hours for this programme. Proposers should take account of the information on instrumentation etc. as per the standard application round and be able to demonstrate the feasibility of their proposal.

Dr Stewart Eyres, Chair, PATT Liverpool Telescope Time Allocation Committee.