https://drupal.star.bnl.gov/STAR/system/files/eSTAR_RD_v0.pdf
https://drupal.star.bnl.gov/STAR/system/files/eSTAR_RD_v1.pdf

R&D projects:
iTPC: populate inner sector padplane and electronics design, mechanic design reducing material
FCS: W-fiber EMC+Sandwich HCAL with SiPMT readout
GEM base TRD
BSO based Crystal EMC: production and test
Endcap TOF: mechnic design, readout design

Other related activities (EIC R&D) possible for eSTAR:

GEM based mini-drift TPC
low mass tracking (GEM?)
HFT'
Electron PID (Cherenkov)