README web version of /home/usg/OPS/MTS/readme_xml/readme_79506400

Principal Investigator Email Address

• pierre.kervella@obspm.fr

Estimated Total Execution Time (hours, including overheads)

• 1.0

General Description

• This programme aims at obtaining NACO photometry in three NB filters and
   H band spectroscopy of a newly detected companion to the bright star Achernar. The
   flux from this companion is expected to be around 2% of the flux of Achernar itself
   in all bands, and it is located at an angular distance of 0.2-0.3". All three OBs
   should be executed together (total time 1.0 hour) in the following sequence: 1-"Achernar",
   2-"Achernar-B-Spectro", 3-"PSF_DeltaPhe". Although this is not mandatory, this will
   save an AO acquisition time between the first and the second OB.
  
  - Imaging: Due to the brightness of Achernar and its PSF calibrator, Delta Phe,
   all imaging observations are done in narrow band filters + neutral density. The
   "Achernar" abd "PSF_DeltaPhe" OBs should be executed in this order one after the
   other. Their execution should not present any particular difficulty, and the exposure
   times have been chosen to allow a large margin before saturation. We have only two
   offset positions as we do not need an accurate sky subtraction. Our PSF calibrator
   is also a spectrophotometric standard and therefore will provide us the necessary
   zero points for our filters.
  
  - Spectroscopy: The exact position of the companion is not known as its orbital
   parameters have not been derived yet. However, an acquisition image obtained in
   June 2007 with NACO for another programme shows the companion at an approximate
   relative position of 90mas West and 190mas North from Achernar, moving apparently
   towards East from last year. The companion should be detectable visually on the
   acquisition image of Achernar using adapted level cuts to display the raw image.
   We set the OB for direct acquisition (zero offset in the acq template).
  *** The night astronomer should check already in the imaging acquisition if the
   companion is detected. *** If not, (s)he should abort the execution and to contact
   USD, so that we can modify the spectroscopy OB to blindly offset from the reference
   star. The orientation of the slit should be East-West, hence the 90 degree position
   angle on sky specified in the acquisition template.
  
  The brightest objects in our fields are Achernar (V=0.5, K=0.9) and Delta Phe (V=4.0,
   K=1.7).

Waiver Requests

• No Waiver Request was submitted

Critical Observing Condition Constraints

• There is no critical observing condition, except as specified in the approved
   proposal.

Time-Critical Aspects

• These observations are not time-critical. However, all three OBs should
   be executed together in a sequence.

Special Execution Requirements

• The three OBs should be executed together.

Special Calibration Information

• None.

ToO Information

• NA

ToO Activators List

• NA

Is this a Pre-imaging run ?

• false

Pre-imaging Requirements

• NA

Source(s) of Pre-imaging

• ---(Empty)---

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 ?

• YES

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 PSF reference star OBs, do the names of those OBs begin with
 PSF_ ?

• YES

If there are Finding Charts attached to your OBs, is the field-of-view
 of at least one of these charts 2' x 2' (with clearly labelled field orientation)
 ?

• YES

Have you clearly marked and labelled your wavefront reference objects
 R1, R2, R3, ... (as specified in the NAOS Preparation Software) on your Finding
 Charts ?

• YES

Have you specified the magnitude of the brightest object in the field-of-view
 for each OB ?

• YES

Are there objects in any of your fields (including standard stars) which
 are brighter than the limits specified in the User Manual and on NACO web Pages
 ?

• NO

If the previous answer is yes, have you given a list of OBs and a justification
 for the brightness limit violation in the general description field ?

• N/A