Requirement:
The placement of each wafer in the global coordinate system of STAR
should have an error of less than 500 
m with respect to the
global origin.
Justification:
This error allows fast tracking for trigger purposes without software correction
Status:
Under discussion
Requirement:
The lock mechanism has to allow x-y adjustments to about 500 
m with
a 25
m accuracy.
Justification:
The two halfs of the SVT have to be adjusted to an accuracy of 25
m to
meet the requirement that the misalignment error is on the order of the
intrinsic resolution.
Status:
The present lock mechanism allows adjustments that meet the requirements
Requirement:
The position of the SVT relative to the beam pipe has to be adjustable
to correct the deflection of the cone structure under stress and the
position error of the manifold. The suggested y-adjustment range is about
5 mm with a 680 
m accuracy..
Justification:
The position with respect to the center of the collision has to be known to about 1 mm so that the misalignment error is on the order of the intrinsic resolution.
Status:
An y-adjustment is provided between the manifold and the cone structure.
Requirement:
The position of the SVT relative to the beam pipe has to be adjustable
with respect to the collision center. The suggested z-adjustment range is about
5 mm with a 250 
m accuracy.
Justification:
The position with respect to the center of the collision has to be known to about 1 mm so that the misalignment error is on the order of the intrinsic resolution.
Status:
A z-adjustment is provided between the manifold and the cone structure. A second z-location adjustment is provided at the end of the support cone (stop) to match the middle of the SVT detector to the collision point. The maximum range is about 3 cm.
Requirement:
After the first installation all adjustment tools have to be locked into position
Justification:
Locking the default values eases subsequent installations.
Status:
The adjustments can be locked to their accuracies after the first installation.
Requirement:
fiducial marks have to be located at the following locations for global alignment.
Justification:
These fiducial marks are required to survey the detector to the required precision
Status:
Fiducial marks are being provided in the mechanical design. Presently four (4) precision 0.062 inch diameter holes are foreseen on each endring.
Requirement:
The global alignment has to be monitored to an accuracy better or equal than the default errors (1 mm).
Justification:
Experience in past collider detector systems show that cycling the power in the magnet or temperature variations in the environment lead to sizeable position shifts in microvertex detectors.
Status:
We plan to adapt the DELPHI capacitive monitoring system for the STAR-SVT.
Requirement:
The detector axis has to be aligned parallel to the magnetic field to better than 10 mrad.
Justification:
This uncertainty meets the momentum resolution requirement without further correction
Status:
Under discussion
Requirement:
The detector x-y location has to be aligned to better than 1 mm with respect to the TPC center.
Justification:
The TPC is aligned to the magnet with a 1 mm uncertainty in the x-y location. The SVT-TPC alignment should contribute less to the accumulated error.
Status:
Under discussion
Requirement:
The detector z-location has to be aligned to better than 1 mm with respect to the most probable interaction point as determined by the VPD.
Justification:
the VPD will generate the trigger accept for the SVT based on the its determination of the interaction point.
Status:
Requirement:
The detector has to be aligned to a 5% uncertainty with respect to a default position.
Justification:
Alignment with respect to default position allows repeatibility of installation
Status:
Under discussion
Requirement:
The fiducial marks on the SVT endcap have to be visible for the survey without major rearrangements of the STAR detector
Justification:
It is anticipated that the SVT will be removed from the main detector for maintenance purposes. The requirement ensures fast and easy relocation.
Status:
Requirement:
The survey tools have to be on axis with the SVT reference points
Justification:
Allows repositioning of SVT without remapping of the exact location.
Status:
Requirement:
All SVT reference points have to be accessible to the surveyers.
Justification:
Allows removal and repositioning of SVT into STAR.
Status:
Requirement:
The exact locations of reference points on the main detector and the floor have to be determined by the SVT group and the STAR integration group before the main detector is positioned in the experimental hall
Justification:
The feasibility of the positioning of the SVT to its specifications has to be simulated, based on accessibility of fiducial marks, before the main detector is in place.
Status: