Studying the Near-horizon Jet of M87 using Millimeter Balloon-borne VLBI stations
Abstract
In this paper we present synthetic Very Long Baseline Interferometry (VLBI) observations of M87 between a near-future configuration of the Event Horizon Telescope (EHT) and one or multiple 2.5 m-class balloon-borne VLBI stations on a northern transatlantic flight trajectory launching from Kiruna, Sweden. These balloon-borne VLBI stations have the advantage of operating above 99.5% of the atmosphere and their motion allows for efficient sampling of the uv-plane. Assuming frequency phase transfer between 230 and 86 GHz we run these simulations using a modified version of the ngehtsim software package. Our simulations demonstrate the ability of such a VLBI array to probe M87 at the jet base adding baselines down to 0.2 Gλ for a single balloon-VLBI station and 0.07 Gλ for three balloon VLBI stations. Using the Bayesian imaging software Comrade.jl, we demonstrate the recovery of jet structures up to 150 μas in size for a single balloon and up to 300 μas in size with three balloons. Finally, we test the improvement in jet image fidelity by computing the normalized cross-correlation (NXCOR) and normalized-root-mean-square error (NRMSE) between the image reconstruction and ground truth. We find a factor of 1.2 improvement in the jet NRMSE for a single balloon and a factor of 1.3 improvement for 3 balloons as compared to EHT-only simulations.
Related
- Energy estimation of direct and reflected cosmic-ray events aboard balloon-borne radio detectors
- Prospects for submillimeter VLBI of black hole photon rings with a stratospheric balloon-borne telescope
- An RFSoC-based Backend and Timing System for the Balloon-borne Very Long Baseline Interferometry Experiment
- Multi-sensor fusion for fine-guidance and milliarcsecond-level attitude estimation of balloon-borne telescope
- The Balloon-borne VLBI Experiment (BVEX) Radio Telescope and Position Tracking System
BibTeX
@misc{thiel2026studying,
title = {{Studying the Near-horizon Jet of M87 using Millimeter Balloon-borne VLBI stations}},
author = {Felix M. Thiel and Dominic W. Pesce and Mayukh Bagchi and Laura M. Fissel and Lindy Blackburn},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.19204},
eprint = {2610.19204},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.19204},
}
RIS
TY - UNPB
TI - Studying the Near-horizon Jet of M87 using Millimeter Balloon-borne VLBI stations
AU - Felix M. Thiel
AU - Dominic W. Pesce
AU - Mayukh Bagchi
AU - Laura M. Fissel
AU - Lindy Blackburn
PY - 2026
DA - 2026/10/13
PB - arXiv
DO - 10.48550/arxiv.2610.19204
UR - https://arxiv.org/abs/2610.19204
AB - In this paper we present synthetic Very Long Baseline Interferometry (VLBI) observations of M87 between a near-future configuration of the Event Horizon Telescope (EHT) and one or multiple 2.5 m-class balloon-borne VLBI stations on a northern transatlantic flight trajectory launching from Kiruna, Sweden. These balloon-borne VLBI stations have the advantage of operating above 99.5% of the atmosphere and their motion allows for efficient sampling of the uv-plane. Assuming frequency phase transfer between 230 and 86 GHz we run these simulations using a modified version of the ngehtsim software package. Our simulations demonstrate the ability of such a VLBI array to probe M87 at the jet base adding baselines down to 0.2 Gλ for a single balloon-VLBI station and 0.07 Gλ for three balloon VLBI stations. Using the Bayesian imaging software Comrade.jl, we demonstrate the recovery of jet structures up to 150 μas in size for a single balloon and up to 300 μas in size with three balloons. Finally, we test the improvement in jet image fidelity by computing the normalized cross-correlation (NXCOR) and normalized-root-mean-square error (NRMSE) between the image reconstruction and ground truth. We find a factor of 1.2 improvement in the jet NRMSE for a single balloon and a factor of 1.3 improvement for 3 balloons as compared to EHT-only simulations.
ER -