README web version of /home/usg/OPS/MTS/readme_xml/readme_82048301

Principal Investigator Email Address

• mjm@astro.ex.ac.uk

Estimated Total Execution Time (hours, including overheads)

• 1.5

General Description

• This long-term FORS2 program monitors the orbital motions of Eps Indi
   Ba,Bb, the nearest known binary brown dwarf system, against a network of background
   field stars. The system has a very high proper motion of 4.7 arcsec/yr. Four epochs
   of observations are needed in P82, spaced roughly by 1 month throughout the period
   when the target is available (Oct-Dec). A dithered set (10 x 20 secs) of FORS2 I-band
   images is taken at each epoch: the SR collimator is used to get a wide field-of-view,
   with the 200kHz,1x1,low read-out mode to simultaneously get best possible spatial
   resolution.
  Target coordinate is an empty point in the sky, roughly where Eps Indi B was in
   late 2007, halfway through a multi-year monitoring campaign. Plan is to use same
   basic pointing for all observations, to ensure same net of field stars is seen throughout.

Waiver Requests

• 381.C-0417B.01.WAV: waiver granted 15/07/08
  Request for extension to Phase 2 submission deadline until 15/08/08
  
  381.C-0417B.02.WAV: waiver granted 15/07/08
  Request to use non-standard 200kHz,1x1,low read-out mode of FORS2 in SR optical
   mode, to ensure both a wide field-of-view to measure a large astrometric reference
   frame, and the best possible spatial resolution, to separate the binary components.

Critical Observing Condition Constraints

• Observations should be made with seeing of 0.6 arcsec or better, in order
   to separate two sources and obtain accurate relative positions. The better the image
   resolution, the better the results. All efforts taken to take data in excellent
   seeing conditions greatly appreciated.
  Clear conditions required for relative photometric measurements within field.

Time-Critical Aspects

• To ensure good sampling of the motions of Eps Indi Ba, Bb, we require
   4 observations roughly evenly spaced throughout P82, i.e. ideally once per month
   while target is available (Oct-Dec). As this clearly depends on schedule, weather,
   etc., spacings of 2-6 weeks would be ok. Thus we have imposed time constraints in
   the OBs with each epoch in a 4 week window, i.e. Sep 15 - Oct 15, Oct 07 - Nov 07,
   Nov 01 - Dec 01, Nov 21 - Dec 21. 
  IMPORTANT: These windows are designed to allow for flexibility (e.g. due to long
   periods of bad weather etc.) and thus they overlap by 1 week. However, in general,
   it does not make sense to execute the OBs for 2 epochs within much less than 2 weeks
   of each other, even if allowed by the time windows in principle. Please try and
   space the epochs evenly throughout P82 as far as possible!

Special Execution Requirements

• The SR mode of FORS2 to be used with 200kHz,1x1 read-out mode to ensure
   a wide field-of-view to get a large astrometric reference frame and the highest
   spatial resolution to separate the binary well.

Special Calibration Information

• Twilight I-band flats required in FORS2 SR/200kHz,1x1 read-out mode: corresponding
   OBs provided.

ToO Information

• N/A

ToO Activators List

• N/A

Is this a Pre-imaging run ?

• false

Pre-imaging Requirements

• N/A

Source(s) of Pre-imaging

• FORS2

Pre-imaging sources not listed above

• ---(Empty)---

Do all your OBs comply with the instrument-specific requirements listed
 on the instrument-specific Phase 2 web page ?

• YES

If this is a pre-imaging run, did you select PRE-IMAGING for the Observing
 Category for each Observing Template ?

• N/A

Do all your finding charts comply with both the general and instrument-specific
 Phase 2 Web Pages ?

• YES

If you submitted OBs for standard stars, did you specify the magnitude
 and spectral type of all standard stars in the OBs ?

• N/A

Have you included OBs for any calibrations that you need but which are
 not part of the Calibration Plan ?

• YES

If you are observing Moving Targets, have you attached suitable ephemeris
 files to your OBs?

• N/A

If you have preferences which OBs should be executed first, did you make
 use of the User Priority field in the OBs ?

• N/A

If this is a run that requires coordinated observations with other facilities,
 did you give proper instructions in the Time-Critical Aspects Section ?

• N/A

If you have prepared your finding charts with tools other than FIMS,
 do they comply with the specifications on the FORS1 Phase 2 web page ?

• YES