APS TECHNICAL UPDATE - No. 17

Enclosed is the Technical Update for inclusion in Section III of your ANL/APS/TB-14 binder.

TUD-17- Errata for ANL/APS TB-20, Bremsstrahlung Scattering Calculations for the Beam Stops and Collimators in the APS Insertion Device Beamline, by Job, et.al.

If you have any questions or need additional information, please contact me. at scd@aps.anl.gov or by phone 630.252.5311.

Subject: Errata for ANL/APS TB-20, Bremsstrahlung Scattering Calculations for the Beam Stops and Collimators in the APS Insertion Device Beamline, by Job, et. al.

1. Section 3b, 1st paragraph, page 5

In the sentence that begins "The cases studied are those in which the extreme rays ..." the center of the aperture should be changed to the edge of the aperture. The sentence should read:

The cases studied are those in which the extreme rays of the bremsstrahlung beam are incident at 1 cm, 0.8 cm and 0.5 cm below the edge of the aperture.

2. Section 3b, 2nd paragraph, page 5

In the sentence that begins " The results are given for three points ..." the center of the aperture should be changed to the edge of the aperture. The sentence should read:

The results are given for three points of incidences, 0.5 cm, 0.8 cm, and 1.0 cm below the edge of the aperture.

3. Shielding Recommendations, Section 4, page 8

In the third bullet, the reference should be the edge of the aperture not the center. The bullet should read:

• For the monochromatic aperture and bremsstrahlung stop in the integral shutter, an offset of 0.8 cm or more is safe for the extremal bremsstrahlung ray for the edge of the mono-aperture.

Updated: October 4, 2007