README web version of /home/usg/OPS/MTS/readme_xml/readme_83008200

Principal Investigator Email Address

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afrebel@cfa.harvard.edu
```

Estimated Total Execution Time (hours, including overheads)

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15.0
```

General Description

The lead (Pb) abundance of HE 1523-0901 is crucial for discriminating
 different r-process models because Pb is the decay product of thorium and uranium,
 which are used for stellar chronometry. We shall detect the Pb line at 4057A to
 provide observational, self-consisting constraints for successful modeling of the
 r-process.

We have chosen the image slicer #2, a 1x1 pixel binning, and the BLUE 437 setting.
 We note that it is neccessary for the Pb detection that we use the image slicer
 #2. It is thus not possible to switch to the image slicer #1 to make use of the
 dicroic mode.

15 exposures of 3000 sec each of HE 1523-0901 with the BLUE 437 setting, image slicer
 #2, and a 0.4" slit shall be taken.

Waiver Requests

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No Waiver Request was submitted
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Critical Observing Condition Constraints

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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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ToO Activators List

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

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?

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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 ?

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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 ?

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N/A
```

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

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N/A
```

Last creation of page: Tue Oct 6 15:40:28 2009
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