Euclid Quick Data Release (Q1). Data processing for intracluster light measurements

@misc{collaboration2026euclid,
  title = {{Euclid Quick Data Release (Q1). Data processing for intracluster light measurements}},
  author = {Euclid Collaboration and S. P. Bamford and H. Gao and N. A. Hatch and T. Kolcu and A. Fernandez and G. Martin and Y. M. Bahé and J. B. Golden-Marx and A. H. Gonzalez and H. Gully and M. Montes and M. Urbano and M. Kluge and P. -A. Duc and D. Scott and B. Altieri and S. Andreon and N. Auricchio and C. Baccigalupi and M. Baldi and S. Bardelli and P. Battaglia and A. Biviano and M. Bolzonella and E. Branchini and M. Brescia and S. Camera and V. Capobianco and C. Carbone and V. F. Cardone and J. Carretero and M. Castellano and G. Castignani and S. Cavuoti and A. Cimatti and C. Colodro-Conde and G. Congedo and C. J. Conselice and L. Conversi and Y. Copin and F. Courbin and H. M. Courtois and M. Cropper and J. -C. Cuillandre and H. Degaudenzi and G. De Lucia and H. Dole and F. Dubath and X. Dupac and S. Escoffier and M. Farina and R. Farinelli and F. Faustini and S. Ferriol and P. Fosalba and S. Fotopoulou and M. Frailis and E. Franceschi and M. Fumana},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.29682},
  eprint = {2610.29682},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.29682},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Euclid Quick Data Release (Q1). Data processing for intracluster light measurements
AU  - Euclid Collaboration
AU  - S. P. Bamford
AU  - H. Gao
AU  - N. A. Hatch
AU  - T. Kolcu
AU  - A. Fernandez
AU  - G. Martin
AU  - Y. M. Bahé
AU  - J. B. Golden-Marx
AU  - A. H. Gonzalez
AU  - H. Gully
AU  - M. Montes
AU  - M. Urbano
AU  - M. Kluge
AU  - P. -A. Duc
AU  - D. Scott
AU  - B. Altieri
AU  - S. Andreon
AU  - N. Auricchio
AU  - C. Baccigalupi
AU  - M. Baldi
AU  - S. Bardelli
AU  - P. Battaglia
AU  - A. Biviano
AU  - M. Bolzonella
AU  - E. Branchini
AU  - M. Brescia
AU  - S. Camera
AU  - V. Capobianco
AU  - C. Carbone
AU  - V. F. Cardone
AU  - J. Carretero
AU  - M. Castellano
AU  - G. Castignani
AU  - S. Cavuoti
AU  - A. Cimatti
AU  - C. Colodro-Conde
AU  - G. Congedo
AU  - C. J. Conselice
AU  - L. Conversi
AU  - Y. Copin
AU  - F. Courbin
AU  - H. M. Courtois
AU  - M. Cropper
AU  - J. -C. Cuillandre
AU  - H. Degaudenzi
AU  - G. De Lucia
AU  - H. Dole
AU  - F. Dubath
AU  - X. Dupac
AU  - S. Escoffier
AU  - M. Farina
AU  - R. Farinelli
AU  - F. Faustini
AU  - S. Ferriol
AU  - P. Fosalba
AU  - S. Fotopoulou
AU  - M. Frailis
AU  - E. Franceschi
AU  - M. Fumana
PY  - 2026
DA  - 2026/10/21
PB  - arXiv
DO  - 10.48550/arxiv.2610.29682
UR  - https://arxiv.org/abs/2610.29682
AB  - The Euclid survey provides images with extraordinary potential for studies of the low-surface-brightness Universe, including intracluster light (ICL). However, to realise this promise, the data must be carefully treated to minimise background variations while preserving the signal from diffuse structures. In this work, we describe the post-processing and measurement procedures used for studies of ICL with Euclid. We demonstrate that we are able to substantially reduce background variations without resorting to a small-scale background subtraction. By injecting simulated clusters into the real images, we show that our approach preserves the faint outskirts of extended sources. On scales of several arcminutes, we can reliably detect surface-brightness levels around 27.5 mag arcsec^−2 in Y_E, J_E, H_E, and 29 mag arcsec^−2 in I_E. As a result, we can obtain accurate measurements of the ICL in individual clusters from the local Universe out to z~0.8 with uncertainties on the order of 10% in surface brightness, 10 degrees in position angle, and 0.1 in ellipticity. Our ability to measure the diffuse light with Euclid is thus set to meet expectations and revolutionise our understanding of the ICL.
ER  -