Euclid Quick Data Release (Q1): Disc breaks highlight the structural evolution of galaxies through time

@misc{collaboration2026euclid,
  title = {{Euclid Quick Data Release (Q1): Disc breaks highlight the structural evolution of galaxies through time}},
  author = {Euclid Collaboration and P. M. Sanchez-Alarcon and J. Román and S. Comeron and J. H. Knapen and M. Huertas-Company and F. Buitrago and M. Montes and A. S. Borlaff and P. M. Marcum and J. Junais and E. Duran-Camacho and M. N. Le and M. Dunn and H. Dannerbauer and B. Altieri and A. Amara and S. Andreon and N. Auricchio and C. Baccigalupi and M. Baldi and A. Balestra and S. Bardelli and P. Battaglia and A. Biviano and M. Bolzonella and E. Branchini and M. Brescia and J. Brinchmann and S. Camera and G. Cañas-Herrera and V. Capobianco and C. Carbone and J. Carretero and S. Casas and M. Castellano and G. Castignani and S. Cavuoti and K. C. Chambers and A. Cimatti and C. Colodro-Conde and G. Congedo and C. J. Conselice and L. Conversi and Y. Copin and A. Costille and F. Courbin and H. M. Courtois and M. Cropper and A. Da Silva and H. Degaudenzi and G. De Lucia and C. Dolding and H. Dole and F. Dubath and C. A. J. Duncan and X. Dupac and S. Dusini and S. Escoffier and M. Fabricius},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.26877},
  eprint = {2609.26877},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.26877},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Euclid Quick Data Release (Q1): Disc breaks highlight the structural evolution of galaxies through time
AU  - Euclid Collaboration
AU  - P. M. Sanchez-Alarcon
AU  - J. Román
AU  - S. Comeron
AU  - J. H. Knapen
AU  - M. Huertas-Company
AU  - F. Buitrago
AU  - M. Montes
AU  - A. S. Borlaff
AU  - P. M. Marcum
AU  - J. Junais
AU  - E. Duran-Camacho
AU  - M. N. Le
AU  - M. Dunn
AU  - H. Dannerbauer
AU  - B. Altieri
AU  - A. Amara
AU  - S. Andreon
AU  - N. Auricchio
AU  - C. Baccigalupi
AU  - M. Baldi
AU  - A. Balestra
AU  - S. Bardelli
AU  - P. Battaglia
AU  - A. Biviano
AU  - M. Bolzonella
AU  - E. Branchini
AU  - M. Brescia
AU  - J. Brinchmann
AU  - S. Camera
AU  - G. Cañas-Herrera
AU  - V. Capobianco
AU  - C. Carbone
AU  - J. Carretero
AU  - S. Casas
AU  - M. Castellano
AU  - G. Castignani
AU  - S. Cavuoti
AU  - K. C. Chambers
AU  - A. Cimatti
AU  - C. Colodro-Conde
AU  - G. Congedo
AU  - C. J. Conselice
AU  - L. Conversi
AU  - Y. Copin
AU  - A. Costille
AU  - F. Courbin
AU  - H. M. Courtois
AU  - M. Cropper
AU  - A. Da Silva
AU  - H. Degaudenzi
AU  - G. De Lucia
AU  - C. Dolding
AU  - H. Dole
AU  - F. Dubath
AU  - C. A. J. Duncan
AU  - X. Dupac
AU  - S. Dusini
AU  - S. Escoffier
AU  - M. Fabricius
PY  - 2026
DA  - 2026/09/22
PB  - arXiv
DO  - 10.48550/arxiv.2609.26877
UR  - https://arxiv.org/abs/2609.26877
AB  - Changes in the slope of the radial surface brightness profiles of disc galaxies, or disc breaks, encode valuable information about the processes driving disc formation and growth. Until now, due to the resolution and depth required, statistical studies of break types have been limited mostly to the local Universe. We aim to study the structural properties and redshift evolution of disc breaks in a large and statistically representative sample of galaxies out to redshift z=1 using the superb depth and resolution of Euclid. We develop an automatic pipeline to extract and analyse surface brightness profiles of 8748 disc galaxies selected from the Euclid Q1 dataset. The pipeline includes advanced masking, surface brightness profile extraction, integrated photometry and structural parameter measurements, and piecewise modelling to classify galaxies into Types I (pure exponential), Type II (down-bending), Type III (up-bending), and composite break (e.g., Type~II+III, Type~II+II, etc) profiles. We quantify structural parameters such as scale lengths, break radii, and surface brightness levels, and analyse their distributions and redshift dependence. Our automatic method produces reliable masks and deep surface brightness profiles, and classifies galaxy profiles with an estimated accuracy of 70%. Using a subsample of 4385 galaxies with reliable classifications, we find that the most common profiles are Types II, II+III, I, and III. We find substantial evolution in the fraction of disc breaks with time. Type II profiles dominate at low redshift (50%), while Types III and II+III profiles increase in frequency with lookback time, reaching 30% each at z~1. Our study provides the first statistically robust measurement of the evolution of disc break types over 5 Gyr. The observed trends support a scenario in which secular processes replace environmental influences as galaxies mature.
ER  -