Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Cone collimator and acquisition geometry. Bottom: A fixed cone collimator is attached to the front of each photomultiplier tube (PMT) assembly. PMTs are stacked 3‐deep along the axial direction of the scanner (white arrows). Top: Two PMTs on opposing sides of the clamshell. During acquisition the clamshell spin and separates (black arrows indicate motion) causing the fixed focus of each clamshell to sample image space in a spiral.
