README web version of /home/usg/OPS/MTS/readme_xml/readme_83082500

Principal Investigator Email Address

```
jsantos@oats.inaf.it
```

Estimated Total Execution Time (hours, including overheads)

```
8h
```

General Description

The purpose of this observation is to perform a direct measurement of
 the amount of cold gas in the very distant and most massive cluster known to date
 at z>1, XMMUJ2235.3-2557. An initial X-ray analysis points to the presence of
 a 'cool core' in this high-redfshift cluster of galaxies, which, to be confirmed,
 would make this system the most distant cool core cluster known.
We propose to address this question by exploiting the most ubiquitous indication
 of the presence of a cool core: the detection of optical emission lines (H-alfa)
 in the central brightest cluster galaxy (BCG) of XMMUJ2235.3-2557. At the cluster
 redshift, z=1.393, the H-alfa emission is redshifted to the Near Infrared, at 1.57
 um, therefore we use the H-band filter. Since this is a very distant cluster, we
 require a long exposure of the BCG (about 5 hrs) in order to secure the detection
 of the H-alfa emission. This observation will allow us to firmly constrain the timescales
 of the cooling and feedback mechanisms in clusters, and will place a strong leverage
 on the redshift evolution of cool cores.
The Ks(2MASS, Vega) magnitude of the BCG is 17 mag. The other galaxies are fainter
 than 18 mag in Ks.

Waiver Requests

```
No Waiver Request was submitted
```

Critical Observing Condition Constraints

```
None
```

Time-Critical Aspects

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None
```

Special Execution Requirements

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None
```

Special Calibration Information

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None
```

ToO Information

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None
```

ToO Activators List

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None
```

Is this a Pre-imaging run ?

```
false
```

Pre-imaging Requirements

```
None
```

Source(s) of Pre-imaging

```
HST/ACS:ISAAC
```

Pre-imaging sources not listed above

```
SOFI
```

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 ?

```
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 ?

```
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 ?

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 the magnitude of the brightest object in the field in each SINFONI OB?

```
N/A
```

If you are using the AO: Did you indicate for every OB the magnitude of the guide star, and its distance to the target (if any)?

```
N/A
```

If you submitted OBs for standard stars, did you use the provided StandardStar templates?

```
N/A
```

If you are using a specific offset pattern or position angle: did you check carefully the definition in the manual?

Did you make really sure that none of your OBs ever saturates the detector?

If you are using the AO: did you enter the correct Strehl Ratio (on-axis, K-band) AND the seeing value in the constraint set?

```
N/A
```

Last creation of page: Tue Oct 6 15:40:30 2009
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