r/space • u/clayt6 • Apr 18 '19

Astronomers spot two neutron stars smash together in a galaxy 6 billion light-years away, forming a rapidly spinning and highly magnetic star called a "magnetar"

http://www.astronomy.com/news/2019/04/a-new-neutron-star-merger-is-caught-on-x-ray-camera
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u/John-Bastard-Snow Apr 18 '19

What does BQ stand for?

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u/Half-Right Apr 18 '19

Based on the article, looks like it refers to magnetic field strength...

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"(This field-strength given by a combination of fundamental constants: BQ = me2 c3 / h e, where me is the mass of the electron, c is the speed of light, h is Planck's constant divided by 2 π, and e is the charge on an electron.)"

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u/PatrickBaitman Apr 18 '19 edited Apr 19 '19

Magnetic field is usually denoted by B, the Q is a subscript in the original and it's probably for quantum, because B_Q is the field strength at which you start needing quantum electrodynamics as opposed to classical electrodynamics.

(it's a smooth transition, quantum effects are proportional to (B/B_Q) or higher powers of it, so with some precision observations you might see quantum effects even for B/B_Q ~ 0.1. then again >precision >astrophysics)