Privacy and Security Notice

Hall C Target Configuration

For May 2007

David Meekins

May 2, 2007

Target Positions

The following table gives a list of target positions and materials.  (Listed BDS positions are pre corrections for cryo and vacuum motion).  The home position will remove the entire target stack from the beam.

 

 

Solid Target Ladder

The following table gives the target foil position, thicknesses and chemical purities.

 

 

Target Position

Target

Purity

Thickness g/cm2

Empty

n/a

n/a

n/a

BeO

Ta

99.0%

0.2918 0.0003

Carbon

Carbon

99.95%

0.35525 0.00030

Copper

Copper

99.95%

0.17775 0.00015

Iron

Iron

99.5%

0.1187 0.00014

 

Error in thickness is from measurement of area and mass only.  Outside thickness (measured with micrometers) variations in the foils are less than the reported error.  Error also does not include possible voids in materials.

 

Fluid Targets

The following table and describes the cell orientation and wall thicknesses as seen from the top.  The cell material is Al 7075-T6.

The table below gives the thicknesses of the cell wall at each of the 4 lettered positions.  The OD is the outer diameter of the cell.

Cell

Loop

A (mm)

B(mm)

C(mm)

D(mm)

OD (mm)

1

1

0.13840.0013

0.13590.0013

0.12700.0013

0.13080.0013

40.130.0013

2

2

0.12190.0013

0.11810.0013

0.12190.0013

0.12070.0013

40.180.0013

3

3

0.12320.0013

0.12320.0013

0.11940.0013

0.11180.0013

40.160.0013

 

 

Optics Targets

The optics target has 3 positions.  The first position has 3 foils on each at z = 7.5 cm and 0; the second has positions at z = 2 cm; the third has positions at z = 3.8 cm.  The following table gives the foil thickness and positions.  Carbon foils are 99.95% carbon.  Positions less than 0 are upstream from the nominal target center.

 

Position

Z position

Material

Thickness (g/cm2)

3 foil

Z = -7.5 cm

Al 6061-T6

0.2651 0.0020

3 foil

Z=0

Al 6061-T6

0.2658 0.0020

3 foil

Z = 7.5 cm

Al 6061-T6

0.2672 0.0020

2 foil z = 2

z = + 2

Carbon

0.1659 0.0012

2 foil z = 2

z = +-2

Carbon

0.1654 0.0012

2 foil z = 3.8

z = +-3.8

Al 6061-T6

0.2663 0.0020

2 foil z = 3.8

z = +-3.8

Al 6061-T6

0.2600 0.0019

 

Each of these targets is 25 mm wide at the beam interaction point.  Please see picture to get a better view of the configuration.

Dummy Targets

The dummy target consists of 2 aluminum alloy foils placed at z =  2 cm.  The foils are 0.8 cm wide (beam transport x direction).  The following table gives the positions and thicknesses of these foils.  The alloy is Al6061-T6.

 

Foil Number

Position

Thickness (g/cm2)

Foil 1

Upstream foil

0.2658 0.0035

Foil 2

Downstream foil

0.2549 0.0034

 

Pictures

Greg Smith was kind enough to provide the following pictures of the target stack.