Rotation Measure

This document describes calculations related to the Rotation Measure (RM) of FRBs.

Galactic RM

Oppermann et al. (2014) have generated an all-sky map of RM estimates and have provided a public Healpix description of it. We have archived a copy and have added a simple wrapper to generate RM estimates from it. Here is a call to the main method:

from astropy.coordinates import SkyCoord
from frb import rm
repeater_coord = SkyCoord('05h31m58.698s +33d8m52.59s', frame='icrs')
#
RM, RM_err = rm.galactic_rm(repeater_coord)

The value and uncertainty are returned as astropy.units.Quantity objects with units of rad/m^2.