README web version of /home/usg/OPS/MTS/readme_xml/readme_78035500

Principal Investigator Email Address

• akaufer@eso.org

Estimated Total Execution Time (hours, including overheads)

• 9:00:00 (9 hrs OBC allocated)

General Description

• These observations try to obtain for the first time interferometric spectroscopic
   time-series observations of the late-type B 
  supergiant ? Orionis (B8 Ia). From optical Heros observations it is well-established
   that ? Ori has a systematically structured and rotationally modulated stellar wind.
   However, little is known about the actual extent and spatial distribution of these
   structures. The analysis of the wind line-profile and visibility variations in the
   new high-resolution Amber Br? and optical Feros spectra will permit a rigorous assessment
   of the nature of the inhomogeneities in the outer atmospheric layers and the wind
   of this this prototypical star and will for the first time allow to ?picture? the
   structured wind of a hot massive star.
  
  The AMBER observations aim at montioring the target over the complete observing
   period with about one calibrated visibility per month (6 visits in the months November
   to March). The main goal is to obtain a time sequence of differential phase closure
   observations of the Br? line with high spectral resolution (HR-K mode in the 2.159
   - 2.173 micron range). 
  
  The AMBER observations are complemeted by parallel FEROS optical spectroscopy at
   La Silla over the same span.

Waiver Requests

• No Waiver Request was submitted (except for late phase 2 submission)

Critical Observing Condition Constraints

• the nominal constraints for MACAO performance apply.

Time-Critical Aspects

• The execution of the 6 submitted OBs should be distributed over the whole
   observing period.
   
  According to the P78 schedule, 6 service mode blocks are available for the VLTI
   with 
  the UTs in the months from November to March, i.e., 1 Sci OB + 1 Cal OBs should
   be 
  executed per VLTI service mode block. This will lead to the requested one observation
   
  per month over 6 months.
  
  The preferred baseline is UT1-UT3-UT4. 
  The observations should be carried out in the window of +/- 2 hrs from the meridian.
  
  HOWEVER: if scheduling constraints / weather do not allow to fulfill the above requirements,
  observations at higher airmass and with any other UT configuration are acceptable.
  
  Priority has to be given to the monthly visit of the object.

Special Execution Requirements

• none

Special Calibration Information

• No special requirements.
  
  Note, that for the selected calibrator no fringes will be detected on the UT1-UT4
   baseline.
  This is not critical since we aim primarily for differential phase closures information
  across the Br gamma line profile and not for calibrated visibilities.

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

• ---(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 ?

• N/A

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

Did you indicate for each science star OB the corresponding calibrator
 star OB (and vice versa) in the 'Instrument Comments' field ?

• YES

Did you check that your chosen calibrator is bright enough for the instrument
 mode used ?

• YES

If you use calibrator stars which are not in the CalVin database, did
 you specify their characteristics in the README file and in the OBs ?

• N/A