README web version of /home/usg/OPS/MTS/readme_xml/readme_81053801

Principal Investigator Email Address

```
pierre.north@epfl.ch
```

Estimated Total Execution Time (hours, including overheads)

12h for J12027, J14192 and J14472 out of 20 hours allocated

General Description

The purpose of this programme is to detect Lalpha emission envelopes around
five quasars at z=4.5, using deep FORS2 MXU spectra.

There are 4 identical blocks per object, each one containing two
~22mn exposures. The total exposure time per object amounts to about 3.0 hours.
Depth is *the* critical issue for this program. We prefer getting few objects
well exposed rather than shallow spectra of all our objects.

In each field, there are slits not only on the quasar, but also on several
stars, in order to get a good PSF. This is needed, because we want to use the
MCS deconvolution technique to improve the separation between the quasar and
envelope spectra.

Good centering of the masks is critical for the quasars *and* PSF stars, even
though our slits are rather broad. This choice is necessary as quasar Lyman
alpha envelopes are extended.

Waiver Requests

```
No Waiver Request was submitted
```

Critical Observing Condition Constraints

Seeing lower than 0.9", dark and clear sky.

Time-Critical Aspects

```
None
```

Special Execution Requirements

```
None
```

Special Calibration Information

```
None
```

ToO Information

---(Empty)---

ToO Activators List

---(Empty)---

Is this a Pre-imaging run ?

```
false
```

Pre-imaging Requirements

---(Empty)---

Source(s) of Pre-imaging

```
FORS2
```

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 ?

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 ?

```
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
```

If you have prepared your finding charts with tools other than FIMS, do they comply with the specifications on the FORS1 Phase 2 web page ?

```
N/A
```

Last creation of page: Tue Oct 6 15:40:24 2009
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