Pointing Accuracy Improvements for the South Pole Telescope with Machine Learning
Creators
-
Chichura, P. M.1
-
Rahlin, A.1
-
Anderson, A. J.1, 2
- Ansarinejad, B.3
-
Archipley, M.1
-
Balkenhol, L.4, 5
- Benabed, K.4, 5
-
Bender, A. N.1, 6
-
Benson, B. A.1, 2
-
Bianchini, F.7, 8
-
Bleem, L. E.1, 6
-
Bouchet, F. R.4, 5
- Bryant, L.1
-
Camphuis, E.4, 5
-
Carlstrom, J. E.1, 6
- Chang, C. L.1, 6
- Chaubal, P.3
- Chokshi, A.1
-
Chou, T.-L.1
- Coerver, A.9
-
Crawford, T. M.1
-
Daley, C.10, 11
- Haan, T. de12
- Dibert, K. R.1
- Dobbs, M. A.13, 14
- Doohan, M.3
- Doussot, A.4, 5
-
Dutcher, D.15
- Everett, W.16
- Feng, C.11
-
Ferguson, K. R.17, 18
- Fichman, K.1
-
Foster, A.15
- Galli, S.4, 5
- Gambrel, A. E.1
- Gardner, R. W.1
- Ge, F.19
- Goeckner-Wald, N.7
-
Gualtieri, R.20
- Guidi, F.4, 5
- Guns, S.9
- Halverson, N. W.16
- Hivon, E.4, 5
-
Holder, G. P.11
- Holzapfel, W. L.9
- Hood, J. C.1
- Hryciuk, A.1
- Huang, N.9
- Kéruzoré, F.6
- Khalife, A. R.4, 5
-
Kim, J.21
- Knox, L.19
- Korman, M.22
- Kornoelje, K.1
- Kuo, C.-L.7, 8
- Levy, K.3
-
Lowitz, A. E.1, 23
- Lu, C.11
- Maniyar, A.7, 8
-
Marrone, D. P.23
- Martsen, E. S.1
- Menanteau, F.11, 24
-
Millea, M.9
- Montgomery, J.13
- Nakato, Y.7
- Natoli, T.1
-
Noble, G. I.25
- Omori, Y.1
- Padin, S.1, 26
-
Pan, Z.1, 6
- Paschos, P.1
-
Phadke, K. A.11, 24
- Pollak, A. W.1
- Prabhu, K.19
- Quan, W.1, 6
- Rahimi, M.3
-
Reichardt, C. L.3
- Rouble, M.13
- Ruhl, J. E.22
-
Schiappucci, E.3
-
Sobrin, J. A.1, 2
- Stark, A. A.27
- Stephen, J.1
- Tandoi, C.11
- Thorne, B.19
- Trendafilova, C.24
-
Umilta, C.11
- Veitch-Michaelis, J.1
-
Vieira, J. D.11, 24
- Vitrier, A.4, 5
- Wan, Y.11, 24
-
Whitehorn, N.18
-
Wu, W. L. K.7, 8
- Young, M. R.1, 2
- Zagorski, K.1
- Zebrowski, J. A.1, 2
-
1.
University of Chicago
-
2.
Fermilab
-
3.
University of Melbourne
-
4.
Institut d'Astrophysique de Paris
-
5.
Sorbonne University
-
6.
Argonne National Laboratory
-
7.
Stanford University
-
8.
SLAC National Accelerator Laboratory
-
9.
University of California, Berkeley
-
10.
CEA Saclay
-
11.
University of Illinois Urbana-Champaign
-
12.
High Energy Accelerator Research Organization
-
13.
McGill University
-
14.
Canadian Institute for Advanced Research
-
15.
Princeton University
-
16.
University of Colorado Boulder
-
17.
University of California, Los Angeles
-
18.
Michigan State University
-
19.
University of California, Davis
-
20.
Northwestern University
-
21.
Korea Advanced Institute of Science and Technology
-
22.
Case Western Reserve University
-
23.
University of Arizona
-
24.
National Center for Supercomputing Applications
-
25.
University of Toronto
-
26.
California Institute of Technology
-
27.
Harvard-Smithsonian Center for Astrophysics
Abstract
In this paper, we present improvements to the pointing accuracy of the South Pole Telescope (SPT) using machine learning. The ability of the SPT to point accurately at the sky is limited by its structural imperfections, which are impacted by the extreme weather at the South Pole. Pointing accuracy is particularly important during SPT participation in observing campaigns with the Event Horizon Telescope (EHT), which requires stricter accuracy than typical observations with the SPT. We compile a training dataset of historical observations of astronomical sources made with the SPT-3G and EHT receivers on the SPT. We train two XGBoost models to learn a mapping from current weather conditions to two telescope drive control arguments — one which corrects for errors in azimuth and the other for errors in elevation. Our trained models achieve root mean squared errors on withheld test data of 2.′′14 in cross-elevation and 3.′′57 in elevation, well below our goal of 5′′ along each axis. We deploy our models on the telescope control system and perform further in situ test observations during the EHT observing campaign in April 2024. Our models result in significantly improved pointing accuracy: for sources within the range of input variables where the models are best trained, average combined pointing error improved 33%, from 15.′′9 to 10.′′6. These improvements, while significant, fall shy of our ultimate goal, but they serve as a proof of concept for the development of future models. Planned upgrades to the EHT receiver on the SPT will necessitate even stricter pointing accuracy which will be achievable with our methods.
Copyright and License
© 2025 World Scientific Publishing Co Pte Ltd.
Acknowledgement
The South Pole Telescope program is supported by the National Science Foundation (NSF) through Awards OPP-1852617 and OPP-2332483. Partial support is also provided by the Kavli Institute of Cosmological Physics at the University of Chicago. Argonne National Laboratory's work was supported by the U.S. Department of Energy, Office of High Energy Physics, under Contract DE-AC02-06CH11357. The University of California, Davis group acknowledges support from Michael and Ester Vaida. Work at Fermi National Accelerator Laboratory, a DOE-OS, HEP User Facility managed by the Fermi Research Alliance, LLC, was supported under Contract No. DE-AC02-07CH11359. The Melbourne authors acknowledge support from the Australian Research Council's Discovery Project scheme (No. DP210102386). The Paris group has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant Agreement No. 101001897), and funding from the Centre National d'Etudes Spatiales. The SLAC group is supported in part by the Department of Energy at SLAC National Accelerator Laboratory, under Contract DE-AC02-76SF00515. PMC, TMC, AEL, and DPM acknowledge support from NSF Award AST-2034306. Preprint of an paper submitted for consideration in the Journal of Astronomical Instrumentation 2024.
Additional details
Related works
- Is new version of
- Discussion Paper: arXiv:2412.15167 (arXiv)
Funding
- National Science Foundation
- OPP-1852617
- National Science Foundation
- OPP-2332483
- United States Department of Energy
- DE-AC02-06CH11357
- United States Department of Energy
- DE-AC02-07CH11359
- Australian Research Council
- DP210102386
- European Union
- 101001897
- Centre National d'Études Spatiales
- United States Department of Energy
- DE-AC02-76SF00515
- National Science Foundation
- AST-2034306
Dates
- Accepted
-
2025-04-23
- Available
-
2025-07-02Published