README web version of /home/usg/OPS/MTS/readme_xml/readme_78075002

Principal Investigator Email Address

• verhoeff@science.uva.nl

Estimated Total Execution Time (hours, including overheads)

• 10 hours

General Description

• Dust evolution in Herbig Be stars.
  
  We intend to determine the disk mineralogy, structure and evolution of Herbig Be
   stars. Most of these massive stars are still shrouded in their natal clouds and
   other nebulosity. This is why the high spatial resolution spectroscopic data of
   VISIR is vital in order to diffentiate the mineralogy of the disks from that of
   their surroundings as observed in the bigger beam of ISO and Spitzer. Subsequently
   we will compare the disk structure and composition to those of the lower mass Herbig
   Ae and T Tauri stars for which comprensive studies have been completed. This observing
   run concerns the imaging of the spatial distribution of the mid-IR emission.
  
  *)Target Identification
  All finding charts are K-band 2MASS images and thus at a diffent wavelength. Most
   targets will be straight forward, because we expect them to be the brightest point
   source in the FOV. Some targets will contain nebulosity or even fragmented cores.
   For the pre-imaging please place the brightest nucleus in the center of the chip.
  
  *)Proper motion
  The proper motion of all targets is less than 0.05"/yr and no ephemeris files are
   needed.

Waiver Requests

• No Waiver Request was submitted

Critical Observing Condition Constraints

• None

Time-Critical Aspects

• None

Special Execution Requirements

• *)Execution requirements
  We selected 30" parallel chop-nodding to clearly discern the environment of the
   objects. Use of the rotator is made for most sources and the chopping-angle is always
   chosen equal to the rotation-angle. 
  Note to the telescope operator: 
  Please observe a guide star that remains in the field with this chop-nod sequence.
  
  *)Note 2007-03-06 !
  In an attempt to eliminate the artifacts on the top and bottom of bright sources
   we have added imaging OBs which contain rotations of 90 degrees with respect to
   the previous images. Another way to avoid the artifacts would be to lower the DIT,
   as we believe it is a saturation effect. So we would like to request to set the
   wheather flag one step lower than usual.

Special Calibration Information

• N/A

ToO Information

• N/A

ToO Activators List

• N/A

Is this a Pre-imaging run ?

• false

Pre-imaging Requirements

• *)Pre-imaging requirements
  All targets of this run are pre-imaging. Based on results of this run we will determine
   the desired slit position and orientation for the subsequent spectroscopic run.
  
  
  Good luck...

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 ?

• 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 the provided finding chart is at a different wavelength than the observations,
 did you clearly describe in the README file how to identify the target?

• YES

Did you specify a guide star brighter than V=12mag within a field of
 r=5arcmin around the science target?

• N/A