The detectors will place high demands on tracking and vertexing systems, which will need to have excellent momentum resolution as well as acceptance over a very large solid angle (as close to 4π as possible). These detectors should also have very low mass, to minimize pair conversions and multiple scattering; the latter is important for low-momentum tracking. And, since tracking systems form the core of any EIC detector, the design should be compact, to allow more space for particle identification, and/or to reduce the size and cost of the detectors that surround it.

The Berkeley EIC group designed a ‘straw-man’ EIC tracking and vertexing system [1] that can meet the requirements set in the EIC Yellow Report process. Figure 1 shows a cross-section of the detector. It consists of a central barrel, with endcap disks on each end. The 6 cylindrical barrel layers roughly cover the region |pseudorapidity|<1, at radii out to 43 cm, with 5 disks on each end. Each endcap consists of 5 disks, from 25 cm to 121 cm upstream/downstream of the nominal interaction point, providing coverage up to |pseudorapidity|<3.5. This compact arrangement leaves room for different particle identification systems at larger radii. The design was a group effort, with 21 authors contributing to Ref. [1].