Updates to Advanced LIGO and Virgo's Low-Latency Electromagnetic Follow-Up Program

Data from Advanced LIGO (and soon, Virgo) is promptly analyzed to enable electromagnetic follow-up observations by dozens of observing teams. In this talk I present three key changes made to this program for the second observing run, O2. These key changes cover (1) down-selecting from multiple gravitational wave triggers to the event candidate we follow-up on, provided these triggers all describe the same astrophysical event, (2) upgrading to 3-dimensional sky localization probability maps (skymaps) for compact binary coalescence events, and (3) providing additional information about event candidates that will be communicated via GCN notices/VOEvents to our observing partners. I will conclude by describing online low-latency pipelines.