Difference between revisions of "Standard Beamline Quadrupole Specification"
From GlueXWiki
m |
|||
(14 intermediate revisions by the same user not shown) | |||
Line 1: | Line 1: | ||
− | Below is the spec for a standard JLAB QP magnet. At 19amps, it can just make the spec for the Hall D tagger. | + | Below is the spec for a standard JLAB QP magnet. At 19amps, it can just make the field spec for the Hall D tagger. |
− | <table bgcolor="#e0e0f0"> | + | <table> |
− | < | + | <tr bgcolor="#e0e0f0"><td>Bore</td><td align="right">3.81 cm</td><td>1.5 in</td></tr> |
− | <tr><td>Length</td><td>30.48 cm</td></tr> | + | <tr bgcolor="#e0e0f0"><td>Length</td><td align="right">30.48 cm</td><td> </td></tr> |
− | <tr><td>Max B'l</td><td>75 kG</td><td>at 18 A (design current)</td></tr> | + | <tr bgcolor="#e0e0f0"><td>Max B'l</td><td align="right">75 kG</td><td>at 18 A (design current)</td></tr> |
− | <tr><td> </td><td>82 kG</td><td>at 19 A (depends on cable run)</td></tr> | + | <tr bgcolor="#e0e0f0"><td> </td><td align="right">82 kG</td><td width="60%">at 19 A (depends on cable run)</td></tr> |
− | </table. | + | </table> |
+ | |||
+ | <i>Response from G. Yang:</i><br> | ||
+ | To get the proper vertical focusing for the 2D microscope readout at the focal plane at 3 GeV [9 GeV photons], the quadrople should have a field gradient of ~0.8 kG/cm and a length of 30.48 cm, or an integrated field gradient of 25 kG. If we intend to move the microscope to 5 GeV or higher-energy electron positions, the field gradient should only be slightly larger. So the capacity of the standard JLab QP magnet is fine. | ||
+ | |||
+ | Remaining questions are: | ||
+ | # The difference between the 25 kG requirement stated above and the 80 kG stated in the specification. Why was such a large margin built into the specification? | ||
+ | # How does cable run length control whether or not the quadrupole can reach 82 kG? Isn't that a power supply issue? | ||
+ | # What are the inner diameters of standard pipe sizes that fit through this bore? Can we find one that meets the 30±2 mm ID in the specification? |
Latest revision as of 16:04, 21 January 2008
Below is the spec for a standard JLAB QP magnet. At 19amps, it can just make the field spec for the Hall D tagger.
Bore | 3.81 cm | 1.5 in |
Length | 30.48 cm | |
Max B'l | 75 kG | at 18 A (design current) |
82 kG | at 19 A (depends on cable run) |
Response from G. Yang:
To get the proper vertical focusing for the 2D microscope readout at the focal plane at 3 GeV [9 GeV photons], the quadrople should have a field gradient of ~0.8 kG/cm and a length of 30.48 cm, or an integrated field gradient of 25 kG. If we intend to move the microscope to 5 GeV or higher-energy electron positions, the field gradient should only be slightly larger. So the capacity of the standard JLab QP magnet is fine.
Remaining questions are:
- The difference between the 25 kG requirement stated above and the 80 kG stated in the specification. Why was such a large margin built into the specification?
- How does cable run length control whether or not the quadrupole can reach 82 kG? Isn't that a power supply issue?
- What are the inner diameters of standard pipe sizes that fit through this bore? Can we find one that meets the 30±2 mm ID in the specification?