README web version of /home/usg/OPS/MTS/readme_xml/readme_80505302
Principal Investigator Email Address
Estimated Total Execution Time (hours, including overheads)
General Description
The goal of this DDT is to observe simultaneously on UT1 with CRIRES and
on UT2 with UVES+FORS1 the bright comet 8P/Tuttle. Those observations will be done
on two different nigths (the closest the 2 nights are in time, the best it is).
CRIRES is run(A), UVES is run(B) and FORS1 is run(C).
The observations on both telescopes need to be coordinated (both telescopes available).
The observation will last for 4 hours on each telescope (in parallel) starting from
beginning of astronomical twilight (the comet is setting).
As the comet is also getting fainter, the soonest the observation are done, the
better it is (before Feb 10 in any case).
CLR or PHO weather and low humidity is important for the success of the observations.
run (A) : On UT1 there are 6 OBs to execute consecutively each night : 2 science
OBs (2 different settings A and B) of 1.5h + 3 telluric (before, between with the
2 settings and after) and 1 flux std star (with both settings). The order of execution
and other info are given in special execution requierements.
run (B) : On UT2 there are 2 OBs to execute consecutively each night with UVES :
one science OB with DIC#1 (note that the blue setting is non std with 348nm central
wavelength) and one science OB with the DIC#2.
run (C) : After the 2 UVES OBs are done there in each night one FORS1 LSS OBs with
several offsets to executed + one "sky" OB to take a spectrum of the sky 30 min
away in RA.
NB : As the target is a fast moving object it is of course needed to update the
coordinates and diff velocities in the OB before execution (using 5min by 5min ephemeris
provided).
This general description is the same for the 3 runs but the other subpanels (for
instance special calibrations, special execution requierements) are specific for
each instrument.
Waiver Requests
Critical Observing Condition Constraints
Time-Critical Aspects
This run is simultaneous with run(A) on UT1 !
Both telescopes need to be available in service mode simultaneously for 4 hours
in a row and since the beginning of the night. This needs to be coordinated between
each telescope operators.
The FORS1 observations are coming after the 2 UVES OBs. They should be started at
about 03:00 UT so to have enouh time on the comet before it is sets. The "Sky" OB
can be done when the comet is below 20 deg.
As the comet is also getting fainter, the soonest the observation are done, the
better it is (before Feb 10 in any case).
Special Execution Requirements
OB execution order
---------------------
There are 2 OBs provided for each night (n1 and n2). The comet OB (MOV_8P_n1) needs
to be done first.
Then the sky_n1 OB to take a 10 min spectrum of the night sky. Please put the same
coordinates as the comet and add 30 min in RA to be far enough from the comet coma.
Large offsets
--------------
The comet OB takes 2 10 min spectra on the central region of the coma and then 3
offsets of 6 arcminutes are applied in the tail direction. The guide star will most
probably be lost. IT IS NOT NEEDED to do a new acquisition if this is happening!
We are indeed far in the diffuse coma and there is nothing to center precisely.
If the telescope goes back to 2-5 arcsec from position by taking the new GS that's
ok as long as it stays to that position for the complete exposure.
More important is that the guide probe does not cross the slit at any time.
Fast moving target !
-------------------
The coordinates *and* the differential tracking rates have to be to be updated in
the OBs before execution. 2 min step ephemeris have been provided. The position
angle is also given in the last column and needs to be updated in the acquisition
template (close to -75 deg because change of sign for FORS) once per night.
Be carreful with the change of date in UT ! Few minutes after the night starts there
is a change of date in UT.
Choice of guide star
-------------------
Warn the TiO about the choice of the guide star, to not take it too close to the
center of the field of view neither to close to the edge. The comet is moving mostly
towards the south so a good GS would be to the South of the field. That's mostly
critical for the first 20 minutes (spectra on the central part) after that, the
GS can be changed.
Special Calibration Information
- we need the usual specphot std star with the MOS slit open at the position
of the 1.0 arcsec LSS slit (MOS_LSS_1.0arcsec)
- The goal of the "sky OB" is to take a night sky LSS spectrum just after the comet
OB is done (coord = same as comet + 30 min in RA)
- If there is time in the morning twilight (best effort) or an other evening twilight
in clear conditions it would be nice to get a bright sky (nautical twilight) spectrum
of the slit, to get the slit response fonction. This could be done by reexecuting
the "sky" OB provided. But we dont have included time for that.
ToO Information
ToO Activators List
Is this a Pre-imaging run ?
Pre-imaging Requirements
Source(s) of Pre-imaging
Pre-imaging sources not listed above
Do all your OBs comply with the instrument-specific requirements listed
on the instrument-specific Phase 2 web page ?
If this is a pre-imaging run, did you select PRE-IMAGING for the Observing
Category for each Observing Template ?
Do all your finding charts comply with both the general and instrument-specific
Phase 2 Web Pages ?
If you submitted OBs for standard stars, did you specify the magnitude
and spectral type of all standard stars in the OBs ?
Have you included OBs for any calibrations that you need but which are
not part of the Calibration Plan ?
If you are observing Moving Targets, have you attached suitable ephemeris
files to your OBs?
If you have preferences which OBs should be executed first, did you make
use of the User Priority field in the OBs ?
If this is a run that requires coordinated observations with other facilities,
did you give proper instructions in the Time-Critical Aspects Section ?
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 ?
Last creation of page: Tue Oct 6 15:40:22 2009
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