README web version of /home/usg/OPS/MTS/readme_xml/readme_80031800
Principal Investigator Email Address
Estimated Total Execution Time (hours, including overheads)
General Description
The goal is to complete the radial-velocities curves for a sample of LMC
Cepheids with an accuracy better than about 500m/s per observation. The
stars have V magnitudes between 12 and 14.5 depending on period and
phase and the bulk of the program was carried out in visitor mode in P76 complemented
by a significant amount of data obtained in service mode in P78.
Our velocity accuracy requirement (500m/s) is not extremely high for HARPS
and we can achieve the goal easily based on the standard calibration of
HARPS done in the beginning and end of the night.
We need a S/N of around 2 in the best orders to get good fits with the
G star template.
The main complication is that we need to fill the gaps in the radial
velocity curves and as the periods of the targets are between 18 and
48 days this leaves us very few chances during the observing period
to actually catch the stars in the appropriate phases, please see the
section on time-critical aspects.
The provided finding charts shows the targets quite well, the Cepheids
being the brightest objects within the circle in each chart.
Waiver Requests
Critical Observing Condition Constraints
Time-Critical Aspects
As we need to fill in the missing phases in the radial velocity curves
we have computed the phase for each star on all the service mode nights
as well as the technical/setup nights and checked where we have matches
for each star. The good phase matches have been entered in the standard
"Time Interval" constraint set for each OB and we have made an OB
corresponding to each missing phase point. In this way a phase point is
completed whenever an OB is executed.
Note that many phase points can only be reached on one single night
and some of these might even be technical nights, i.e. non service mode
nights. We hope that it will still be possible to execute at least some
of these OBs as this is really our only chance of completing these radial
velocity curves.
As the periods for the stars are quite long a typical time window is
24hours long as given in the OB Time Interval constraint set.
Special Execution Requirements
Special Calibration Information
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 ?
Last creation of page: Tue Oct 6 15:40:21 2009
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