README web version of /home/usg/OPS/MTS/readme_xml/readme_84039301

Principal Investigator Email Address

• akaufer@eso.org

Estimated Total Execution Time (hours, including overheads)

• 7:00:00 (7 hrs OPC allocated)

General Description

• These observations try to obtain  interferometric spectroscopic time-series
   observations of the late-type B supergiant beta Orionis (Rigel, B8 Ia). From optical
    observations it is well-established that beta 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 Brgamma and optical 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 every second week (12 visits in the
   months October to March, 5 with the ATs (run A), 7 with the UTs (run B)). 
  
  The main goal is to obtain a time sequence of differential visibilities, differential
   phase and closure phase observations of the Brgamma line with high spectral resolution
   (HR-K mode in the full 2.149 - 2.195 micron range). 
  
  First VLTI observations of this object have been obtained in P78 with the UTs in
   HRK mode but without FINITO and resulted in poor data quality. This repetition with
   FINITO and the ATs and UTs is expected do deliver a superior data set.
  
  The AMBER observations are complemeted by parallel optical high-resolution spectroscopy
   at other observatories over the same time span.

Waiver Requests

• No Waiver Request was submitted

Critical Observing Condition Constraints

• Given by FINITO requirements. AM<1.5, Seeing <0.8 (UT) < 1.2
   (AT), Clear

Time-Critical Aspects

• The execution of the 24 submitted OBs (10 in run A for the ATs and 14
   in run B for the UTs) should be distributed over the whole observing period.
   
  According to the P84 schedule one observation (calibrated visibility) has to be
   obtained in every UT and AT VLTI slot over the period. A possible execution sequence
   could be:
  
  1	26-Oct-09	UT1-UT3-UT4	B betaOri-0
  2	03-Nov-09	UT1-UT3-UT4	B betaOri-1
  3	17-Nov-09	A0-K0-G1	A betaOri-0
  4	05-Dec-09	UT1-UT3-UT4	B betaOri-2
  5	23-Dec-09	A0-K0-G1	A betaOri-1
  6	30-Dec-09	UT1-UT3-UT4	B betaOri-3
  7	18-Jan-10	A0-K0-G1	A betaOri-2
  8	30-Jan-09	UT1-UT3-UT4	B betaOri-4
  9	10-Feb-10	A0-K0-G1	A betaOri-3
  10	28-Feb-09	UT1-UT3-UT4	B betaOri-5
  11	18-Mar-09	A0-K0-G1	A betaOri-4
  12	25-Mar-09	UT1-UT3-UT4	B betaOri-6
  
  The preferred baselines are A0-K0-G1 (run A) and UT1-UT3-UT4 (run B).  
  The observations should be carried out in the window of +/- 2 hrs from the meridian
   and airmass <1.5.
  
  HOWEVER: if scheduling constraints / weather do not allow to fulfill the above requirements,
  observations at higher airmass without FINITO and with any other UT or AT triplett
   configuration are acceptable.
  
  Priority has to be given to the time sampling over the period.

Special Execution Requirements

• cf. time requirements for monitoring

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

Do you use the same DIT for pairs of science target and associated calibrator?

• YES

Are the magnitudes of science target and calibrator within +/- 1 mag
 ?

• YES

Did you verify that your coordinates are as accurate as possible (2Mass
 coordinates recommended) and that they include proper motions if available ?

• YES

Did you specify the LST range of the calibrators such that they cover
 the range from 30 min before the start of the LST range of the science target to
 30 min after the end of the LST range of the science target ?

• YES