README web version of /home/usg/OPS/MTS/readme_xml/readme_79052100

Principal Investigator Email Address

• Eric.Stempels@st-andrews.ac.uk

Estimated Total Execution Time (hours, including overheads)

• 22

General Description

• The goal of this program is to obtain high-resolution and high signal-to-noise
   spectra of the binary T Tauri star V4046 Sgr, following the system throughout its
   orbital period. These spectra will be used to construct surface intensity maps of
   both stars, showing the starspot distributions.
  
  Because the spot distribution is expected to change slowly, we need to cover the
   entire rotational phase in a relatively short period. The period of the system is
   2.4 days, which makes it possible to obtain a full cycle of phase coverage in 5
   consecutive nights. After completion of one full cycle, the observations should
   be repeated for a second cycle (about 1-2 weeks later). This will allow us to determine
   the change in surface structure between the two cycles.
  
  In addition to V4046 Sgr, we include a few spectral and telluric templates. The
   telluric template (HD 177756) should be observed once every night that V4046 Sgr
   is observed.

Waiver Requests

• No Waiver Request was submitted

Critical Observing Condition Constraints

• Losing a single exposure or even a whole night in a five-night cycle due
   to, for example, bad weather does not damage the observed cycle beyond repair. Losing
   two nights does. In that case we prefer to follow the system for as long as the
   service period allows (and the OBs last).

Time-Critical Aspects

• In order to obtain full homogeneous phase coverage, V4046 Sgr, the main
   target, should be observed 4 x 900s in 5 consecutive nights. This requires that
   the program is started at the first of at least 5 consecutive service nights.
  
  Within each night, the exposures should happen at approx. 2h-intervals (for example,
   at 21, 23, 01, and 03 hours). The exaxt timing of these observations is not critical
   to the minute. These 4x5=20 exposures are in individual OBs, numbered 1-20.
  
  V4046 Sgr is in opposition on 21 June 2007, so the schedule is only feasible at
   reasonable airmasses between May 15 and July 30 2007. The first exposure of the
   night should be started before the altitude of V4046 Sgr reaches 60 degrees, because
   otherwise the last exposure will finish at an altitude less than 30 degrees. (The
   optimal altitude to start the first exposure is 48 degrees, which occurs arount
   ST=15h15m).
  
  The moon passes very close to V4046 Sgr on June 3, June 30 and July 27/28. This
   will break our observing constraint of moon distance > 15 degrees. These dates
   should thus be avoided when planning to start a 5-day cycle on V4046 Sgr.
  
  The OBs are divided in two cycles. Each cycle gives one full phase coverage of V4046
   Sgr. The two cycles should be separated by 1-2 weeks (ideally, or longer if scheduling
   requires that).
  
  The telluric template (HD 177756) should be observed once on each night that V4046
   Sgr is observed. The spectral templates (the GJ and GL stars) can be observed at
   any time during P79.

Special Execution Requirements

• None.

Special Calibration Information

• None. Standard calibrations will be just fine.

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 ?

• YES

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 you need secondary guiding, are there suitable objects within 30 arcsec
 from your target ?

• N/A