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Hit resolution

The formula used for the pad resolution function was taken from STAR note # 34 [4]. The resolution function is
equation817
where tex2html_wrap_inline2466 is the drift distance (taken in meters), tex2html_wrap_inline2468 is the crossing angle, and tex2html_wrap_inline2470 is the inverse of an attenuation factor. The recommended values are tex2html_wrap_inline2472m, tex2html_wrap_inline2474m (for tex2html_wrap_inline2466 in meters), and tex2html_wrap_inline2478m, and tex2html_wrap_inline2480 is taken to be zero. The code uses the values of tex2html_wrap_inline2482 to avoid calculating a lot of squares. Also, GEANT uses centimeters rather than meters, then tex2html_wrap_inline2484 cm.

The resolution in the y direction is taken as a constant, tex2html_wrap_inline2488. The recommended value is tex2html_wrap_inline2490 cm.

For one pad hits (those which are above the value of HITTHRESHOLD and below the value of ONEPADTH) the position is rounded to the center of the nearest pad row by making the value of x of the form tex2html_wrap_inline2394, where N is an integer, and XPADSIZE is the width (in x) of a pad. The value of the resolution returned (DX) is tex2html_wrap_inline2390.



E895 common account
Wed Aug 6 16:32:35 EDT 1997