README web version of /home/usg/OPS/MTS/readme_xml/readme_80028800

Principal Investigator Email Address

```
petitjean@iap.fr
```

Estimated Total Execution Time (hours, including overheads)

```
32 hours
```

General Description

Constraining the time variation of dimensionless physical constants is
 crucial for our understanding of physics. We propose to use the unique capabilities
 of UVES to strengthen the constraint on the variation of the electron-to-proton
 mass ratio 
(mu=me/mp) by measuring precisely the wavelength of molecular hydrogen transitions
 in high-redshift damped Lyman-$\alpha$ systems. We have discovered  two new H2 bearing
 DLAs presenting close to ideal characteristics for such measurement:
(i) large redshift, z=2.402 and 2.658, 
(ii) simple absorption profile, a single Gaussian and 
(iii) intermediate H$_2$ column densities, log N(H2)=17.30 and 18.41, with absorptions
 from several rotational levels.
Together with the two systems from the literature (Ivanchik et al. 2005), these
 new observations will yield about 150 aborption lines. About thirty will be in common
 to at least two quasars. This will definitely solve the issue of a variation of
 mu at a level achievable with present-day instrumentation.

Waiver Requests

We have attached a ThAr calibration exposure to each of the science exposure.
 Therefore the total time for each OB exceeds a little the 1 hour limit.

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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Not applicable
```

ToO Activators List

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Not applicable
```

Is this a Pre-imaging run ?

```
false
```

Pre-imaging Requirements

```
None
```

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 ?

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 ?

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N/A
```

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

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?

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

```
N/A
```

Last creation of page: Tue Oct 6 15:40:21 2009
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