Jefferson Lab Alignment Group

DATA TRANSMITTAL

 

TO: P. Ulmer, J. Gomez, N. Liyanage, J. LeRose            DATE: Jul 3, 2002 

FROM:  Chris Curtis                                                            Checked:                              # : A790

DETAILS:

            Below are the results from the spectrometer pointing and superharp surveys carried out on the Electron (left) and Hadron (right) arms on June 25^th, 2002. For the superharps, the values represent the difference in millimeters from the ideal position of each fiducial. A positive X value is to the beam left, a positive Y is too high.

 

 

            ================ RESULTS =============== E062502A

 

            The central ray of the spectrometer is at  -74.979 degrees.

            It is missing the defined target center by   3.10 mm   upstream,

            and   -0.54 mm vertically (positive = up).

 

            If the offset is corrected by secondary alignment, the

            spectrometer will be at  285.000 degrees.

 

            *.9PR : 0.107             *.3DD : 1.28

 

           

            ================ RESULTS =============== H062502A

 

            The central ray of the spectrometer is at   66.270 degrees.

            It is missing the defined target center by   0.12 mm   upstream,

            and    2.12 mm vertically (positive = up).

 

            If the offset is corrected by secondary alignment, the

            spectrometer will be at   66.271 degrees.

 

            9PR : 0.096               *.3DD : 1.86

 

 

                        Superharps                                                             

                                                   DX                 DY                   locations in mm (+ is beam left)

 

            SH1H01A                   0.19               0.30

            SH1H01B                   0.31               0.29

            SH1H01C                   0.31               0.28

 

            SH1H02A                  -0.08               0.26

            SH1H02B                   0.03               0.29

            SH1H02C                   0.01               0.34