A low-latency pipeline for GRB light curve and spectrum using Fermi/GBM near real-time data

Rapid response and short time latency are very important for Time Domain Astronomy, such as the observations of Gamma-ray Bursts (GRBs) and electromagnetic (HM) counterparts of gravitational waves (GWs). Based on near real-time FermilGBM data, we developed a low-latency pipeline to automatically calculate the temporal and spectral properties of GRBs. With this pipeline, some important parameters can be obtained, such as T-90 and fluence, within similar to 20 min after the GRB trigger. For similar to 90% of GRBs, T-90 and fluence are consistent with the GBM catalog results within 2 sigma errors. This pipeline has been used by the Gamma-ray Bursts Polarimeter (POLAR) and the Insight Hard X-ray Modulation Telescope (Insight-HXMT) to follow up the bursts of interest. For GRB 170817A, the first HM counterpart of GW events detected by FermilGBM and INTIiGRAL/SPI-ACS, the pipeline gave T-90 and spectral information 21 min after the GBM trigger, providing important information for POLAR and Insight-HXMT observations.