학술논문

Absolute Flux Density Calibration of the Greenland Telescope Data for Event Horizon Telescope Observations
Document Type
Working Paper
Source
Subject
Astrophysics - Instrumentation and Methods for Astrophysics
Language
Abstract
Starting from the observing campaign in April 2018, the Greenland Telescope (GLT) has been added as a new station of the Event Horizon Telescope (EHT) array. Visibilities on baselines to the GLT, particularly in the North-South direction, potentially provide valuable new constraints for the modeling and imaging of sources such as M87*. The GLT's location at high Northern latitudes adds unique challenges to its calibration strategies. Additionally, the performance of the GLT was not optimal during the 2018 observations due to it being only partially commissioned at the time. This document describes the steps taken to estimate the various parameters (and their uncertainties) required for the absolute flux calibration of the GLT data as part of the EHT. In particular, we consider the non-optimized status of the GLT in 2018, as well as its improved performance during the 2021 EHT campaign.
Comment: 17 pages, 4 figures, EHT Memo Series 2023-L1-02