They would no longer have to pay taxes.

Randal Munro's comment in a what if comes to mind: "You wouldn't really die of anything, you would just stop being biology and start being physics"

I mean, technically you're in one right now. Some of them just randomly point in our direction. But I'm sure you mean up close.

It's particles going a significant fraction of the speed of light, but you may well have a few of those going through you as we speak. I don't know how much is known about how wide they are exactly, or how dense, but it's possible you'd die slowly from radiation poisoning rather than of anything more dramatic.

Some things look a lot more impressive from far away, like nebulae, which are almost perfect vacuums that are just a bit less perfect than their surroundings.

To shreds you say

I did a little snooping and found someone claiming to have a source on the diameter of a jet, but their link went nowhere. I think it's this though. Anyway, at 0.05 light years across and presumed circular, a human body purposefully over estimated to have a cross sectional area of 2m^2, would be subject to 28.5 gigawatts.

Wolfram Alpha very kindly points out that this is the equivalent of nearly two and a half space shuttles blasting you, boosters and all. Good luck!

I've no idea how accurate this is, but googling gave me an estimate of the energy required that suggests it would take a little less than three seconds to vaporize an entire body. If it can create a plasma, that counts as subatomic in my books, but I've no idea what that would take.

Nuclear would depend more on the particle kinematics and I've got no intuition there tbh. I'm sure it's certainly possible though, especially if you get close.

The quasar wouldn't do anything that the vacuum hadn't already done...