README web version of /home/usg/OPS/MTS/readme_xml/readme_60942600

Principal Investigator Email Address

• kw113@star.le.ac.uk

Estimated Total Execution Time (hours, including overheads)

• 1.5

General Description

• This run is aimed at X-shooter spectroscopy of the optical counterpart
   of the eclipsing
  X-ray binary XTE J1710-281. 
  The aim is to detect the emission lines of the accretion disk of this system as
   well as the stellar emission of the secondary star (the donor) and possibly the
   synchrotron emission of a
  relativistic jet.
  
  The orbital period of this system is 3.28 hours, as found by measurements with XMM
   and XTE. The source shows pronounced X-ray eclipses lasting 410 seconds. 
  We discovered the optical counterpart of this sytem with EFOSC2 on the ESO 3.6m,
   with magnitudes R=19.9, I=19.7. We do not know the infrared magnitudes of the source,
   but it is expected to be around J=17-18 based on the system parameters and the secondary
   type. 
  Magnitudes bluewards of R band are not known. We made OBs for short exposures (600
   seconds in NIR, 510 in UVB and VIS), so we sample part of the orbital period reasonably
   well. Note that the source is expected to show emission lines (the continuum may
   be very faint or undetected in individual 510 sec frames).
  
  As the source has R<20, the OBs are for direct acquisition, with a conservative
   60 second acquisition exposure time. It is possible that the source is somewhat
   variable in optical wavelengths - though we have no evidence of that so far.
  We use the STARE mode, as the field is highly crowded, and no high spatial resolution
   nIR imaging exists, which makes the chance of finding an adequate "sky" position
   too small.
  
  This program consists of 2 OBs, due to the 1 hour constraint on OB length. If these
   are 
  executed sequentially, feel free to omit the acquisition part of the second OB if
   desirable.
  Note that these OBs do not NEED to be done sequentially, they may be done on different
   nights if needed, as we have good knowledge of the orbital period.
  
  NB: 2 finder charts are submitted because of the highly crowded nature of the field.
   The first one shows the full 2x2' FoV, the second one a zoom on the target with
   the slit angle plotted, to better make the target visible. Both charts are made
   with EFOSC2 R band data.

Waiver Requests

• No Waiver Request was submitted

Critical Observing Condition Constraints

• N/A

Time-Critical Aspects

• N/A

Special Execution Requirements

• N/A

Special Calibration Information

• Standard calibrations will suffice. We have no strong preference for a
   particulary type of telluric standard, as we do not know which emission lines to
   expectin the binary.

ToO Information

• N/A

ToO Activators List

• N/A

Do all your OBs comply with the instrument-specific requirements listed
 on the instrument-specific Phase 2 web page ?

• YES

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 specified the S/N ratio at given wavelength in the User Comments
 field of each OB?

• 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 ?

• 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