A census of Dark Energy Survey Year 3 redMaPPer galaxy clusters in a high exposure eROSITA All Sky Survey region

@article{giles2026census,
  title = {{A census of Dark Energy Survey Year 3 redMaPPer galaxy clusters in a high exposure eROSITA All Sky Survey region}},
  author = {P.A Giles and A.K Romer and J Pilling and R Wilkinson and D.J Turner and T Jeltema and A Farahi and M.E Ramos-Ceja and F Balzer and M Kluge and S Grandis and E Bulbul and M Hilton and S Bhargava and E Aljamal and A.E Evrard and E.W Upsdell and P.T.P Viana and A Abdulghafour and M Aguena and S.S Allam and O Alves and F Andrade-Oliveira and D Bacon and D Brooks and R Camilleri and A Carnero Rosell and J Carretero and M Costanzi and L.N da Costa and J de Vicente and S Desai and P Doel and C Doux and B Flaugher and J Frieman and J Garc and M Gatti and D Gruen and G Gutierrez and S.R Hinton and D.L Hollowood and K Honscheid and K Kuehn and O Lahav and S Lee and J.L Marshall and J Mena-Fernández and F Menanteau and R Miquel and R.C Nichol and R.L.C Ogando and A.A Plazas Malagón and S Samuroff and E Sanchez and D Sanchez Cid and M Smith and M.E da Silva Pereira and M Soares-Santos and E Suchyta},
  journal = {Mon.Not.Roy.Astron.Soc.},
  year = {2026},
  month = oct,
  doi = {10.1093/mnras/stag1747},
  eprint = {2610.16742},
  archivePrefix = {arXiv},
  url = {https://hal.science/hal-05828761v1},
  note = {CC BY 4.0},
}

TY  - JOUR
TI  - A census of Dark Energy Survey Year 3 redMaPPer galaxy clusters in a high exposure eROSITA All Sky Survey region
AU  - P.A Giles
AU  - A.K Romer
AU  - J Pilling
AU  - R Wilkinson
AU  - D.J Turner
AU  - T Jeltema
AU  - A Farahi
AU  - M.E Ramos-Ceja
AU  - F Balzer
AU  - M Kluge
AU  - S Grandis
AU  - E Bulbul
AU  - M Hilton
AU  - S Bhargava
AU  - E Aljamal
AU  - A.E Evrard
AU  - E.W Upsdell
AU  - P.T.P Viana
AU  - A Abdulghafour
AU  - M Aguena
AU  - S.S Allam
AU  - O Alves
AU  - F Andrade-Oliveira
AU  - D Bacon
AU  - D Brooks
AU  - R Camilleri
AU  - A Carnero Rosell
AU  - J Carretero
AU  - M Costanzi
AU  - L.N da Costa
AU  - J de Vicente
AU  - S Desai
AU  - P Doel
AU  - C Doux
AU  - B Flaugher
AU  - J Frieman
AU  - J Garc
AU  - M Gatti
AU  - D Gruen
AU  - G Gutierrez
AU  - S.R Hinton
AU  - D.L Hollowood
AU  - K Honscheid
AU  - K Kuehn
AU  - O Lahav
AU  - S Lee
AU  - J.L Marshall
AU  - J Mena-Fernández
AU  - F Menanteau
AU  - R Miquel
AU  - R.C Nichol
AU  - R.L.C Ogando
AU  - A.A Plazas Malagón
AU  - S Samuroff
AU  - E Sanchez
AU  - D Sanchez Cid
AU  - M Smith
AU  - M.E da Silva Pereira
AU  - M Soares-Santos
AU  - E Suchyta
PY  - 2026
DA  - 2026/10/12
JO  - Mon.Not.Roy.Astron.Soc.
DO  - 10.1093/mnras/stag1747
UR  - https://hal.science/hal-05828761v1
AB  - We present the cross-match of galaxy clusters detected by redMaPPer using the first three years of Dark Energy Survey (DESY3RM) operations, and the first release of the eROSITA-All Sky Survey (eRASS1) taken by eROSITA on board the Spectrum Roentgen Gamma telescope. We define a sky region (60^∘<R.A.<90^∘ and −58^∘<Dec<−48^∘) whereby the mean eRASS1 exposure time of clusters falling within this footprint is ∼2.5 times longer than the mean exposure time of the full eRASS1--DESY3RM overlap. Limiting to a redshift range 0.2 < z < 0.65 and redMaPPer estimated richnesses to >50, we obtain a sample of 57 clusters. We match these clusters to the cluster catalogue constructed for the eRASS1, finding 45 clusters with a match and 12 with no match in the catalogue. X-ray properties of the 12 unmatched clusters are estimated via a forced photometry analysis. We investigate the form of the luminosity-richness relation, finding the relation using the full 57 cluster sample is statistically consistent with using only the 45 matched clusters, and will require the deeper data of future eRASS releases (or dedicated X-ray follow-up) to explore further potential differences. Using external data from XMM, ACT and SPT, we find detections of 5 of the 12 unmatched clusters, indicating the presence of virialised gas. Finally, we found the 12 unmatched clusters occupy a higher redshift range and lower richness range (compared to the matched clusters), and find no evidence for an underlying physical reason for the lack of X-ray emission.
ER  -