I think it is saying that there is a pulsar called Vela.
This pulsar shoots out photons which are really high energy (X-rays).
These photos are extremely polarized (aligned).
There is a limit to how highly aligned photons can become in a natural process (in this case an environment with extremely strong magnetic forces at work)
Given how highly aligned these photons are, they are able to make some educated guesses about the environment the X-rays are passing through (a nebula surrounding the pulsar), and possibly about the nature of the pulsar itself.
Edgetiger t1_j1h0agu wrote
Reply to Vela pulsar wind nebula X-rays are polarized to near the synchrotron limit by wmdolls
I’ll take a stab at this.