This part is called YE+1, one piece of the two end-caps from the CMS detector experiment at the CERN Large Hadron Collider. Based on hundreds of images downloaded from the CERN document server. Modeled in Autodesk Fusion360. You can explore the model on my Autodesk profile. Those last images it's just the same model but black-themed, like it should be :)
CMS Detector - Large Hadron Collider 3D Model
02 October, 2017
Compact Muon Solenoid Detector 3D model at the CERN Large Hadron Collider