README web version of /home/usg/OPS/MTS/readme_xml/readme_83070502

Principal Investigator Email Address

• roccata@mpia.de

Estimated Total Execution Time (hours, including overheads)

• 2

General Description

• Our goal is to directly detect and study the structure of the circumstellar
   dust around both sources of the young binary system SVS 20. The different luminosities
   of the two components may be responsible for the different amounts of crystalline
   silicate emission observed in each component in the mid-infrared wavelength range.
   The lower luminosity of the northern component (SVS 20 N) may have caused longer
   processing times for the circumstellar material, although the apparent presence
   of crystalline emission indicates that, even for lower mass young stellar objects,
   crystallization occurs relatively early in the star formation process. We propose
   to investigate the inner region at small scale where the crystallization processes,
   e.g. by annealing, take place. At a small scale informations on the emission and/or
   absorption of the silicate and crystalline features can as well constrain the inclination
   of the two disks.
  
  The coordinates of SVS 20 S (N ~ 4 Jy) are RA: 18h29m57.74s and DEC: +01 14 05.7
   (2MASS peak). SVS 20 N (N ~ 2 Jy) is separated from SVS 20 S by 1\".5 (~375 AU)
   at a position angle of 9.9deg.

Waiver Requests

• No Waiver Request was submitted

Critical Observing Condition Constraints

• Since the science objects have a V-band magnitude of less than 18 and
   within 1 arcmin there is only a faint guide star, the observations require excellent
   seeing conditions (<0.8\") and the full moon has to be at least 15 deg away from
   the science targets. The H-band magnitudes of the science targets are below the
   detection limit of the 2MASS catalogue.
  
  Important: If the guide star is too faint, please observe the science targets AND
   the calibrators without the MACAO system!
  
  Important: Before starting the interferometric observations it has to be made sure
   that the telescopes are pointing on the wanted source within the close double system
   (see \"Special Execution Requirements\")
  
  Important: We suggest to start the observations with SVS 20S (2x brighter) and then
   to proceed with SVS 20N.

Time-Critical Aspects

• No

Special Execution Requirements

• Important: If the guide star is too faint, please observe the science
   targets AND the calibrators without the MACAO system!
  
  Important: Before starting the interferometric observations it has to be made sure
   that the telescopes are pointing on the wanted source within the close double system.
   Therefore, the position(s) 1.5'' north AND/OR 1.5'' south of the position the telescope
   was originally pointing to have/has to be investigated. If a source 1.5'' north
   of the original position is found, the telescope was pointing originally at SVS
   20S. If a source 1.5'' south of the original position is found, the telescope was
   pointing originally at SVS 20 N.

Special Calibration Information

• HD173074:
  Position =  18 43 37.3700 -1 33 32.5000
  Distance = 4.59985 deg
  Diameter =  2.45000 +- 0.470000 marcsec
  Spectral Type: M...
  Vmag = 7.22000 mag
  Hmag = 2.16000 mag
  N (Iras) = 6.32000 Jy
  Simbad Remark: Star
  Hipparcos-defined type of variability: unsolved variable which does
  not fall in the other categories.
  Source: \"MIDI Calibrator List (Stecklum et al.)\".

ToO Information

• ---(Empty)---

ToO Activators List

• ---(Empty)---

Is this a Pre-imaging run ?

• false

Pre-imaging Requirements

• ---(Empty)---

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 ?

• 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