The MAGPI Survey: the evolution of galaxy spin–filament alignments since z∼0.3
21 affiliations
- 1Sydney Institute for Astronomy (SIfA), School of Physics, The University of Sydney , NSW 2006 ,
- 2International Centre for Radio Astronomy Research, University of Western Australia , 7 Fairway, Crawley, WA 6009 ,
- 3Research School of Astronomy and Astrophysics, Australian National University , Cotter Road, Weston Creek, ACT 2611 ,
- 4School of Physics, University of New South Wales , Sydney, NSW 2052 ,
- 5Institute for Computational Cosmology, Durham University Department of Physics, , South Road, Durham DH13LE ,
- 6Centre for Extragalactic Astronomy, Durham University Department of Physics, , South Road, Durham DH13LE ,
- 7School of Mathematical and Physical Sciences, Macquarie University , Sydney, NSW 2109 ,
- 8Astrophysics and Space Technologies Research Centre , Macquarie University, Sydney, NSW 2109 ,
- 9Tartu Observatory, University of Tartu , Observatooriumi 1, 61602, Tõravere ,
- 10Instituto de Astrofísica e Ciências do Espaço - Centro de Astrofísica da Universidade do Porto , Rua das Estrelas, 4150-762 Porto ,
- 11School of Mathematics and Physics, University of Queensland , St Lucia, Queensland 4072 ,
- 12Institut d’Astrophysique de Paris, UMR 7095, CNRS, and Sorbonne Université , 98 bis boulevard Arago, 75014 Paris ,
- 13Universitäts-Sternwarte, Fakultät für Physik, Ludwig-Maximilians-Universität München , Scheinerstr. 1, 81679 München ,
- 14Centre for Astrophysics, and Supercomputing, Swinburne University of Technology , Hawthorn, VIC 3122 ,
- 15University of Strasbourg, CNRS UMR 7550, Observatoire astronomique de Strasbourg , F-67000 Strasbourg ,
- 16SISSA – International School for Advanced Studies , Via Bonomea 265, I-34136 Trieste ,
- 17UWC – University of the Western Cape , Department of Physics and Astronomy, Cape Town 7535 ,
- 18IFPU – Institute for Fundamental Physics of the Universe , Via Beirut, 2, 34151 Trieste ,
- 19INFN – Sezione di Trieste , via Valerio 2, I-34127 Trieste ,
- 20University of Vienna Department of Astrophysics, , Türkenschanzstraße 17, 1180 Vienna ,
- 21INAF – Osservatorio Astronomico di Trieste , Via Tiepolo 11, I-34131 Trieste ,
Abstract
We present measurements of galaxy spin-filament alignments at 0.20 < z < 0.42 using the MAGPI Survey, exploiting resolved stellar and ionised gas kinematics to reconstruct 3D spin axes. Cosmic filaments are identified using a stellar mass-matched constant-number-density population from the GAMA, MAGPI Redshift Survey and DESI datasets. We detect a flipping of the statistical alignment signal at z ∼ 0.3 as a function of M⋆: low-mass galaxies preferentially exhibit spins parallel to the direction of their host filaments, while high-mass galaxies tend towards perpendicular orientations. The transition mass is measured to be log (M⋆, t/M⊙) ≃ 10.8, approximately 0.6 dex higher than the value for the SAMI Galaxy Survey at z ∼ 0.05. Bootstrap analysis gives 99.5% confidence that the transition mass is higher for MAGPI than SAMI. At fixed stellar mass MAGPI galaxies exhibit stronger parallel alignments than their SAMI counterparts, suggesting evolution of spin–filament alignments over the past ∼ 3 Gyr. The gaseous component in MAGPI galaxies is more closely aligned with filaments than the stellar component, relative to a M⋆-matched SAMI sample. This indicates a stronger coupling between ionised gas and the large-scale structure at z ∼ 0.3, consistent with coherent gas accretion onto filaments remaining efficient at higher M⋆. At z ∼ 0 we detect a transition toward perpendicular alignments at lower M⋆, while the gas and stellar components exhibit similar alignments relative to filaments, likely due to the cumulative effects of mergers and secular evolution.
Related
- The MAGPI Survey: Emission Line Products Data Release and the Role of Spectroscopic Aperture Covering Fraction on the Balmer Decrement-Stellar Mass Relation
- The "Fork" Geometry in the DESI Main Survey DR1: Implications of Target Selection for Galaxy Evolution Studies
- The “Fork” Geometry in the DESI Main Survey DR1: Implications of Target Selection for Galaxy Evolution Studies
- Model-Independent Assessments of Tidal Alignment and Density-Weighting Dependence in Galaxy Intrinsic Alignments
- The MAGPI survey: Stellar population radial trends and mass assembly in star-forming galaxies at z~0.3
BibTeX
@article{barsanti2026magpi,
title = {{The MAGPI Survey: the evolution of galaxy spin–filament alignments since z∼0.3}},
author = {Stefania Barsanti and Andrew J Battisti and Sabine Bellstedt and Matthew Colless and Scott M Croom and Caroline Foster and Katherine E Harborne and Claudia D P Lagos and J Trevor Mendel and Matt S Owers and Elmo Tempel and Emily Wisnioski and Iris Breda and Pratyush K Das and Clotilde Laigle and Rhea-Silvia Remus and Gauri Sharma and Sabine Thater and Lucas M Valenzuela and Jesse van de Sande and Glenn van de Ven and Daria Zakharova and Bodo L Ziegler},
journal = {Monthly Notices of the Royal Astronomical Society},
year = {2026},
month = oct,
doi = {10.1093/mnras/stag2078},
url = {https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2078/9005959},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - The MAGPI Survey: the evolution of galaxy spin–filament alignments since z∼0.3
AU - Stefania Barsanti
AU - Andrew J Battisti
AU - Sabine Bellstedt
AU - Matthew Colless
AU - Scott M Croom
AU - Caroline Foster
AU - Katherine E Harborne
AU - Claudia D P Lagos
AU - J Trevor Mendel
AU - Matt S Owers
AU - Elmo Tempel
AU - Emily Wisnioski
AU - Iris Breda
AU - Pratyush K Das
AU - Clotilde Laigle
AU - Rhea-Silvia Remus
AU - Gauri Sharma
AU - Sabine Thater
AU - Lucas M Valenzuela
AU - Jesse van de Sande
AU - Glenn van de Ven
AU - Daria Zakharova
AU - Bodo L Ziegler
PY - 2026
DA - 2026/10/31
JO - Monthly Notices of the Royal Astronomical Society
DO - 10.1093/mnras/stag2078
UR - https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag2078/9005959
AB - We present measurements of galaxy spin-filament alignments at 0.20 < z < 0.42 using the MAGPI Survey, exploiting resolved stellar and ionised gas kinematics to reconstruct 3D spin axes. Cosmic filaments are identified using a stellar mass-matched constant-number-density population from the GAMA, MAGPI Redshift Survey and DESI datasets. We detect a flipping of the statistical alignment signal at z ∼ 0.3 as a function of M⋆: low-mass galaxies preferentially exhibit spins parallel to the direction of their host filaments, while high-mass galaxies tend towards perpendicular orientations. The transition mass is measured to be log (M⋆, t/M⊙) ≃ 10.8, approximately 0.6 dex higher than the value for the SAMI Galaxy Survey at z ∼ 0.05. Bootstrap analysis gives 99.5% confidence that the transition mass is higher for MAGPI than SAMI. At fixed stellar mass MAGPI galaxies exhibit stronger parallel alignments than their SAMI counterparts, suggesting evolution of spin–filament alignments over the past ∼ 3 Gyr. The gaseous component in MAGPI galaxies is more closely aligned with filaments than the stellar component, relative to a M⋆-matched SAMI sample. This indicates a stronger coupling between ionised gas and the large-scale structure at z ∼ 0.3, consistent with coherent gas accretion onto filaments remaining efficient at higher M⋆. At z ∼ 0 we detect a transition toward perpendicular alignments at lower M⋆, while the gas and stellar components exhibit similar alignments relative to filaments, likely due to the cumulative effects of mergers and secular evolution.
SN - 0035-8711
SN - 1365-2966
ER -