System Design for the Event Horizon Imaging Experiment Using the PECMEO Concept

Abstract

The concept for space interferometry from Polar or Equatorial Circular Medium Earth Orbits (the PECMEO concept) is a promising way to acquire the image of the "shadow" of the event horizon of Sagittarius A* with an angular resolution of circa 5 microarcseconds. The concept is intended to decrease the size of the main reflector of the instrument to about 3 m using a precise orbit reconstruction based on Global Navigation Satellite System (GNSS) navigation, inter-satellite range and range-rate measurements, and data from the Attitude and Orbit Determination System (AODS). The paper provides the current progress on the definition of the subsystems required for the concept on the basis of simulations, radio regulations, and available technology. The paper proposes the requirement for the localization of the phase centre of the main reflector. The paper provides information about the visibility of GNSS satellites and the needed accuracies of the AODS. The paper proposes the frequency plan for the instrument and its Inter-Satellite Links (ISLs). The concepts for measurement of range and range rate using ISLs (as well as for the data exchange at these ISLs) are presented. The block diagram of the interferometer is described and its sensitivity is estimated. The link budget for both ISLs is given as well as their critical components. The calculated measurement quality factors are given. The paper shows the expected performance of the sub-systems of the interferometer. The requirements for the localization of the main reflectors and the information about the availability of the GNSS satellites are based on the simulations results. (Two sentences have been deleted in order to satisfy the maximum symbol count established by arXiv rules.) The paper provides input information for the development of the orbit reconstruction filter and the whole PECMEO system.

arXiv comment17 pages, 5 figures

References in corpus (6)

• Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
• Radiative Models of Sgr A* from GRMHD Simulations
• Towards the event horizon -- the supermassive black hole in the Galactic Center
• Far-Infrared Spectroscopy of the Galactic Center. Hot Molecular Gas: Shocks versus Radiation near SgrA*
• Imaging an Event Horizon: Mitigation of Source Variability of Sagittarius A*
• RadioAstron as a target and as an instrument: Enhancing the Space VLBI mission's scientific output

Cited by in corpus (7)

• Simulations of imaging the event horizon of Sagittarius A* from space
• Black hole parameter estimation with synthetic Very Long Baseline Interferometry data from the ground and from space
• Analysis of Orbital Configurations for Millimetron Space Observatory
• An Event Horizon Imager (EHI) Mission Concept Utilizing Medium Earth Orbit Sub-mm Interferometry
• Accurate analytical modeling of light rays in spherically symmetric spacetimes: Applications in the study of black hole accretion disks and polarimetry
• Imaging the event horizon of M87* from space on different timescales
• Effect of Earth's Oblateness on Black Hole Imaging Through Earth-Space and Space-Space VLBI