README web version of /home/usg/OPS/MTS/readme_xml/readme_75505900

Principal Investigator Email Address

```
hxb@mpe.mpg.de
```

Estimated Total Execution Time (hours, including overheads)

```
10.9
```

General Description

This program consists of deep spectroscopic follow-up observations of
two very distant galaxy clusters discovered in our on-going program to
build a sample of z>1 clusters.  These galaxy systems were
serendipitously detected as an extended X-ray source in archival
XMM-Newton observations.  R-z colors measured with FORS2 indicate
cluster redshifts of z>1.  These spectroscopic observations will
validate our overall survey strategy for rapidly and efficiently
building large samples of very distant galaxy clusters.

The observational strategy of the current program is straight forward.
We have designed two FORS2 masks (one per cluster) targeting likely
cluster members based on cuts in magnitude and color.  The more
distant cluster (XMMUJ0159) is our 1st priority followed by the
slightly less distant cluster (XMMUJ0104).

To aid the verification of mask alignment, numerous reference slits
with reasonably bright stars have been included on both masks (2"x2"
square slits).  The fainter target galaxies in some slits may not
appear in the slit image.

Waiver Requests

Waiver request submitted 23 Sep 2005 to exceed 1 hour OB limit.
USD granted on 30 Sep 2005.

Critical Observing Condition Constraints

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N/A
```

Time-Critical Aspects

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N/A
```

Special Execution Requirements

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Special Calibration Information

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ToO Information

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ToO Activators List

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Is this a Pre-imaging run ?

```
false
```

Pre-imaging Requirements

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Source(s) of Pre-imaging

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FORS2
```

Pre-imaging sources not listed above

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

If this is a pre-imaging run, did you select PRE-IMAGING for the Observing Category for each Observing Template ?

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N/A
```

Do all your finding charts comply with both the general and instrument-specific Phase 2 Web Pages ?

If you submitted OBs for standard stars, did you specify the magnitude and spectral type of all standard stars in the OBs ?

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N/A
```

Have you included OBs for any calibrations that you need but which are not part of the Calibration Plan ?

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N/A
```

If you are observing Moving Targets, have you attached suitable ephemeris files to your OBs?

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N/A
```

If you have preferences which OBs should be executed first, did you make use of the User Priority field in the OBs ?

If this is a run that requires coordinated observations with other facilities, did you give proper instructions in the Time-Critical Aspects Section ?

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N/A
```

If you have prepared your finding charts with tools other than FIMS, do they comply with the specifications on the FORS2 Phase 2 web page ?

```
N/A
```

Last creation of page: Tue Oct 6 15:40:09 2009
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