Euclid preparation

Astronomy and Astrophysics, vol. 707, pp. A233

Abstract

Context. The Euclid galaxy survey is designed to measure the spectroscopic redshift of emission-line galaxies (ELGs) by identifying the H α emission line in their slitless spectra. The efficacy of this approach crucially depends on the signal-to-noise ratio (S/N) of the line, as sometimes noise fluctuations in the spectrum continuum can be misidentified as H α . In addition, other genuine strong emission lines can be mistaken for H α , depending on the redshift of the source. Both effects lead to ambiguities in the redshift measurement that can result in catastrophic redshift errors and the inclusion of ‘interloper’ galaxies in the sample. Aims. This paper forecasts the impact on the galaxy clustering analysis of the expected redshift errors in the Euclid spectroscopic sample. Specifically, it investigates the effect of the redshift interloper contamination on the galaxy two-point correlation function (2PCF) and, in turn, on the inferred growth rate of structure fσ 8 and Alcock–Paczynski (AP) parameters α ∥ and α ⊥ . Methods. This work is based on the analysis of 1000 synthetic spectroscopic catalogues, the EuclidLargeMocks, which mimic the area and selection function of the Euclid Data Release 1 (DR1) sample. We estimated the 2PCF of contaminated catalogues and separated the different contributions, particularly those coming from galaxies with correctly measured redshift and from contaminants. We explored different models of increasing complexity to describe the measured 2PCF at a fixed cosmology, with the aim of identifying the most efficient model to reproduce the data. Finally, we performed a cosmological inference and evaluated the systematic error on the inferred fσ 8 , α ∥ , and α ⊥ values associated with different models. Results. Our results demonstrate that a minimal modelling approach, which only accounts for an attenuation of the clustering signal regardless of the type of contaminants, is sufficient to recover the correct values of fσ 8 , α ∥ , and α ⊥ at DR1. The accuracy and precision of the estimated AP parameters are largely insensitive to the presence of interlopers. The adoption of a minimal modelling induces a 1%–3% systematic error on the growth rate of structure estimation, depending on the considered redshift. However, this error remains smaller than the statistical error expected for the Euclid DR1 analysis.

Authors 93

1. I Risso

   National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare, Sezione di Genova · Brera Astronomical Observatory

   Affiliation as printed

   INAF-Osservatorio Astronomico di Brera

   INFN-Sezione di Genova

2. Alfonso Veropalumbo

   National Institute for Astrophysics · University of Genoa · Istituto Nazionale di Fisica Nucleare, Sezione di Genova · Brera Astronomical Observatory

   Affiliation as printed

   Dipartimento di Fisica, Università di Genova

   INAF-Osservatorio Astronomico di Brera

   INFN-Sezione di Genova

3. E. Branchini

   National Institute for Astrophysics · University of Genoa · Istituto Nazionale di Fisica Nucleare, Sezione di Genova · Brera Astronomical Observatory

   Affiliation as printed

   Dipartimento di Fisica, Università di Genova

   INAF-Osservatorio Astronomico di Brera

   INFN-Sezione di Genova

4. Edoardo Maragliano

   University of Genoa · Istituto Nazionale di Fisica Nucleare, Sezione di Genova

   Affiliation as printed

   Dipartimento di Fisica, Università di Genova

   INFN-Sezione di Genova

5. S. de la Torre

   Centre National de la Recherche Scientifique · Aix-Marseille Université

   Affiliation as printed

   Aix-Marseille Université, CNRS, CNES, LAM

6. E Sarpa

   Scuola Internazionale Superiore di Studi Avanzati · Istituto Nazionale di Fisica Nucleare, Sezione di Trieste · Fondazione ICSC Centro Nazionale di Ricerca in High Performance Computing, Big Data e Quantum Computing

   Affiliation as printed

   ICSC – Centro Nazionale di Ricerca in High Performance Computing, Big Data e Quantum Computing

   INFN, Sezione di Trieste

   SISSA, International School for Advanced Studies

7. Pierluigi Monaco

   National Institute for Astrophysics · Trieste Astronomical Observatory · University of Trieste · Istituto Nazionale di Fisica Nucleare, Sezione di Trieste · Institute for Fundamental Physics of the Universe

   Affiliation as printed

   Dipartimento di Fisica - Sezione di Astronomia, Università di Trieste

   IFPU, Institute for Fundamental Physics of the Universe

   INAF-Osservatorio Astronomico di Trieste

   INFN, Sezione di Trieste

8. B. R. Granett

   National Institute for Astrophysics · Brera Astronomical Observatory

   Affiliation as printed

   INAF-Osservatorio Astronomico di Brera

9. S. Lee

   Jet Propulsion Laboratory

   Affiliation as printed

   Jet Propulsion Laboratory, California Institute of Technology

10. Graeme E. Addison

    Johns Hopkins University

    Affiliation as printed

    Johns Hopkins University

11. S Bruton

    California Institute of Technology

    Affiliation as printed

    California Institute of Technology

12. C. Carbone

    National Institute for Astrophysics

    Affiliation as printed

    INAF-IASF Milano

13. Guilhem Lavaux

    Centre National de la Recherche Scientifique · Institut d'Astrophysique de Paris · Sorbonne Université

    Affiliation as printed

    Institut d’Astrophysique de Paris, UMR 7095, CNRS, and Sorbonne Université

14. Katarina Markovic

    Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory, California Institute of Technology

15. G. Parimbelli

    Scuola Internazionale Superiore di Studi Avanzati · University of Genoa · Istituto Nazionale di Fisica Nucleare, Sezione di Genova · Institute of Space Sciences

    Affiliation as printed

    Dipartimento di Fisica, Università degli studi di Genova, and INFN-Sezione di Genova

    Institute of Space Sciences (ICE, CSIC), Campus UAB

    SISSA, International School for Advanced Studies

16. Francesca Passalacqua

    University of Padua · Istituto Nazionale di Fisica Nucleare, Sezione di Padova · Istituto Nazionale di Fisica Nucleare

    Affiliation as printed

    Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova

    INFN-Padova

17. Will J. Percival

    University of Waterloo · Perimeter Institute

    Affiliation as printed

    Department of Physics and Astronomy, University of Waterloo

    Perimeter Institute for Theoretical Physics

    Waterloo Centre for Astrophysics, University of Waterloo

18. C. Scarlata

    University of Minnesota

    Affiliation as printed

    Minnesota Institute for Astrophysics, University of Minnesota

19. E. Sefusatti

    National Institute for Astrophysics · Trieste Astronomical Observatory · Istituto Nazionale di Fisica Nucleare, Sezione di Trieste · Institute for Fundamental Physics of the Universe

    Affiliation as printed

    IFPU, Institute for Fundamental Physics of the Universe

    INAF-Osservatorio Astronomico di Trieste

    INFN, Sezione di Trieste

20. Marco Bonici

    National Institute for Astrophysics · University of Waterloo

    Affiliation as printed

    INAF-IASF Milano

    Waterloo Centre for Astrophysics, University of Waterloo

21. F Oppizzi

    Istituto Nazionale di Fisica Nucleare, Sezione di Genova

    Affiliation as printed

    INFN-Sezione di Genova

22. N. Aghanim

    Centre National de la Recherche Scientifique · Université Paris-Saclay · Institut d'Astrophysique Spatiale

    Affiliation as printed

    Université Paris-Saclay, CNRS, Institut d’astrophysique spatiale

23. A Amara

    University of Surrey

    Affiliation as printed

    School of Mathematics and Physics, University of Surrey

24. Stefano Andreon

    National Institute for Astrophysics · Brera Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Brera

25. N. Auricchio

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

26. Carlo Baccigalupi

    Scuola Internazionale Superiore di Studi Avanzati · National Institute for Astrophysics · Trieste Astronomical Observatory · Istituto Nazionale di Fisica Nucleare, Sezione di Trieste · Institute for Fundamental Physics of the Universe

    Affiliation as printed

    IFPU, Institute for Fundamental Physics of the Universe

    INAF-Osservatorio Astronomico di Trieste

    INFN, Sezione di Trieste

    SISSA, International School for Advanced Studies

27. Marco Baldi

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare, Sezione di Bologna · University of Bologna

    Affiliation as printed

    Dipartimento di Fisica e Astronomia, Università di Bologna

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

    INFN-Sezione di Bologna

28. A. Balestra

    National Institute for Astrophysics · Osservatorio Astronomico di Padova

    Affiliation as printed

    INAF-Osservatorio Astronomico di Padova

29. S. Bardelli

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

30. A. Biviano

    National Institute for Astrophysics · Trieste Astronomical Observatory · Institute for Fundamental Physics of the Universe

    Affiliation as printed

    IFPU, Institute for Fundamental Physics of the Universe

    INAF-Osservatorio Astronomico di Trieste

31. Andrea Bonchi

    Agenzia Spaziale Italiana

    Affiliation as printed

    Space Science Data Center, Italian Space Agency

32. D. Bonino

    National Institute for Astrophysics · Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino

33. M. Brescia

    National Institute for Astrophysics · University of Naples Federico II · Astronomical Observatory of Capodimonte

    Affiliation as printed

    Department of Physics “E. Pancini”, University Federico II

    INAF-Osservatorio Astronomico di Capodimonte

34. J. Brinchmann

    Universidade do Porto · Institute of Astrophysics and Space Sciences · Centro de Astrofísica da Universidade do Porto

    Affiliation as printed

    Faculdade de Ciências da Universidade do Porto

    Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP

35. S. Camera

    National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare, Sezione di Torino · University of Turin · Osservatorio Astrofisico di Torino

    Affiliation as printed

    Dipartimento di Fisica, Università degli Studi di Torino

    INAF-Osservatorio Astrofisico di Torino

    INFN-Sezione di Torino

36. V. Capobianco

    National Institute for Astrophysics · Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino

37. V. F. Cardone

    National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare, Sezione di Roma I · Astronomical Observatory of Rome

    Affiliation as printed

    INAF-Osservatorio Astronomico di Roma

    INFN-Sezione di Roma

38. J. Carretero

    Universitat Autònoma de Barcelona · Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas · Port d'Informació Científica

    Affiliation as printed

    Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)

    Port d’Informació Científica, Campus UAB

39. S Casas Aachen Institute for Theoretical Particle Physics and Cosmology

    RWTH Aachen University

    Affiliation as printed

    Institute for Theoretical Particle Physics and Cosmology (TTK), RWTH Aachen University

40. M Castellano

    National Institute for Astrophysics · Astronomical Observatory of Rome

    Affiliation as printed

    INAF-Osservatorio Astronomico di Roma

41. G. Castignani

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

42. S. Cavuoti

    National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare · Istituto Nazionale di Fisica Nucleare, Sezione di Napoli · Astronomical Observatory of Capodimonte

    Affiliation as printed

    INAF-Osservatorio Astronomico di Capodimonte

    INFN section of Naples

43. K. C. Chambers

    University of Hawaiʻi at Mānoa · University of Hawaii System

    Affiliation as printed

    Institute for Astronomy, University of Hawaii

44. A. Cimatti

    University of Bologna

    Affiliation as printed

    Dipartimento di Fisica e Astronomia “Augusto Righi” – Alma Mater Studiorum Università di Bologna

45. C Colodro-Conde

    Instituto de Astrofísica de Canarias

    Affiliation as printed

    Instituto de Astrofísica de Canarias, Vía Láctea

46. G. Congedo

    University of Edinburgh · Royal Observatory

    Affiliation as printed

    Institute for Astronomy, University of Edinburgh, Royal Observatory

47. Christopher J. Conselice

    University of Manchester

    Affiliation as printed

    Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, University of Manchester

48. L. Conversi

    European Space Agency · European Space Astronomy Centre · European Space Research Institute

    Affiliation as printed

    ESAC/ESA

    European Space Agency/ESRIN

49. F Courbin

    Institut de Ciències del Cosmos · Universitat de Barcelona · Institució Catalana de Recerca i Estudis Avançats

    Affiliation as printed

    Institució Catalana de Recerca i Estudis Avançats (ICREA)

    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB)

50. Hélène M. Courtois

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Institut de Physique des 2 Infinis de Lyon

    Affiliation as printed

    UCB Lyon 1, CNRS/IN2P3, IUF, IP2I Lyon

51. M. Crocce

    Universitat Politècnica de Catalunya · Institute of Space Sciences · Institut d'Estudis Espacials de Catalunya

    Affiliation as printed

    Institut d’Estudis Espacials de Catalunya (IEEC), Edifici RDIT, Campus UPC

    Institute of Space Sciences (ICE, CSIC), Campus UAB

52. A da Silva

    University of Lisbon · Institute of Astrophysics and Space Sciences

    Affiliation as printed

    Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Edifício C8

    Instituto de Astrofísica e Ciências do Espaço, Faculdade de Ciências, Universidade de Lisboa

53. Hubert Degaudenzi

    University of Geneva

    Affiliation as printed

    Department of Astronomy, University of Geneva

54. G. De Lucia

    National Institute for Astrophysics · Trieste Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Trieste

55. Anna M. Di Giorgio

    National Institute for Astrophysics · Institute for Space Astrophysics and Planetology

    Affiliation as printed

    INAF-Istituto di Astrofisica e Planetologia Spaziali

56. H. Dole

    Centre National de la Recherche Scientifique · Université Paris-Saclay · Institut d'Astrophysique Spatiale

    Affiliation as printed

    Université Paris-Saclay, CNRS, Institut d’astrophysique spatiale

57. Marian Douspis

    Centre National de la Recherche Scientifique · Université Paris-Saclay · Institut d'Astrophysique Spatiale

    Affiliation as printed

    Université Paris-Saclay, CNRS, Institut d’astrophysique spatiale

58. F. Dubath

    University of Geneva

    Affiliation as printed

    Department of Astronomy, University of Geneva

59. C. A. J. Duncan

    University of Manchester

    Affiliation as printed

    Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, University of Manchester

60. X Dupac

    European Space Agency · European Space Astronomy Centre

    Affiliation as printed

    ESAC/ESA

61. S. Dusini

    Istituto Nazionale di Fisica Nucleare, Sezione di Padova · Istituto Nazionale di Fisica Nucleare

    Affiliation as printed

    INFN-Padova

62. S. Escoffier

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Aix-Marseille Université · Centre de physique des particules de Marseille

    Affiliation as printed

    Aix-Marseille Université, CNRS/IN2P3, CPPM

63. Maria Farina

    National Institute for Astrophysics · Institute for Space Astrophysics and Planetology

    Affiliation as printed

    INAF-Istituto di Astrofisica e Planetologia Spaziali

64. R. Farinelli

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

65. F Faustini

    National Institute for Astrophysics · Agenzia Spaziale Italiana · Astronomical Observatory of Rome

    Affiliation as printed

    INAF-Osservatorio Astronomico di Roma

    Space Science Data Center, Italian Space Agency

66. S Ferriol

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Lyon 1 Université · Institut de Physique des 2 Infinis de Lyon

    Affiliation as printed

    Université Claude Bernard Lyon 1, CNRS/IN2P3, IP2I Lyon, UMR 5822

67. Fabio Finelli

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare, Sezione di Bologna

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

    INFN-Bologna

68. S. Fotopoulou

    University of Bristol

    Affiliation as printed

    School of Physics, HH Wills Physics Laboratory, University of Bristol

69. N. Fourmanoit

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Aix-Marseille Université · Centre de physique des particules de Marseille

    Affiliation as printed

    Aix-Marseille Université, CNRS/IN2P3, CPPM

70. M. Frailis

    National Institute for Astrophysics · Trieste Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Trieste

71. Enrico Franceschi

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

72. M Fumana

    National Institute for Astrophysics

    Affiliation as printed

    INAF-IASF Milano

73. Samuele Galeotta

    National Institute for Astrophysics · Trieste Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Trieste

74. K. George

    Ludwig-Maximilians-Universität München

    Affiliation as printed

    Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München

75. William Gillard

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Aix-Marseille Université · Centre de physique des particules de Marseille

    Affiliation as printed

    Aix-Marseille Université, CNRS/IN2P3, CPPM

76. Gillis B

    University of Edinburgh · Royal Observatory

    Affiliation as printed

    Institute for Astronomy, University of Edinburgh, Royal Observatory

77. C. Giocoli

    Osservatorio di Astrofisica e Scienza dello Spazio · National Institute for Astrophysics · Istituto Nazionale di Fisica Nucleare, Sezione di Bologna

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna

    INFN-Sezione di Bologna

78. Javier Graciá-Carpio

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max Planck Institute for Extraterrestrial Physics

79. A. Grazian

    National Institute for Astrophysics · Osservatorio Astronomico di Padova

    Affiliation as printed

    INAF-Osservatorio Astronomico di Padova

80. F Grupp

    Ludwig-Maximilians-Universität München · Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max Planck Institute for Extraterrestrial Physics

    Universitäts-Sternwarte München, Fakultät für Physik, Ludwig-Maximilians-Universität München

81. L. Guzzo

    National Institute for Astrophysics · University of Milan · Istituto Nazionale di Fisica Nucleare, Sezione di Milano · Brera Astronomical Observatory

    Affiliation as printed

    Dipartimento di Fisica “Aldo Pontremoli”, Università degli Studi di Milano

    INAF-Osservatorio Astronomico di Brera

    INFN-Sezione di Milano

82. S. V. H. Haugan

    University of Oslo

    Affiliation as printed

    Institute of Theoretical Astrophysics, University of Oslo

83. F. Hormuth
    Affiliation as printed

    Felix Hormuth Engineering

84. Allan Hornstrup

    Technical University of Denmark

    Affiliation as printed

    Cosmic Dawn Center (DAWN)

    Technical University of Denmark

85. Hudelot P

    Centre National de la Recherche Scientifique · Institut d'Astrophysique de Paris · Sorbonne Université

    Affiliation as printed

    Institut d’Astrophysique de Paris, UMR 7095, CNRS, and Sorbonne Université

86. K. Jahnkę

    Max Planck Institute for Astronomy

    Affiliation as printed

    Max-Planck-Institut für Astronomie

87. M. Jhabvala

    Goddard Space Flight Center

    Affiliation as printed

    NASA Goddard Space Flight Center

88. Benjamin Joachimi

    University College London

    Affiliation as printed

    Department of Physics and Astronomy, University College London

89. Keihanen E

    Helsinki Institute of Physics

    Affiliation as printed

    Department of Physics and Helsinki Institute of Physics

90. Smaïn Kermiche

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Aix-Marseille Université · Centre de physique des particules de Marseille

    Affiliation as printed

    Aix-Marseille Université, CNRS/IN2P3, CPPM

91. A. Kiessling

    Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory, California Institute of Technology

92. M. Kilbinger

    Centre National de la Recherche Scientifique · Université Paris-Saclay · Commissariat à l'Énergie Atomique et aux Énergies Alternatives · Astrophysique, Instrumentation et Modélisation · Université Paris Cité

    Affiliation as printed

    Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM

93. Bogna Kubik

    Centre National de la Recherche Scientifique · Institut National de Physique Nucléaire et de Physique des Particules · Lyon 1 Université · Institut de Physique des 2 Infinis de Lyon

    Affiliation as printed

    Université Claude Bernard Lyon 1, CNRS/IN2P3, IP2I Lyon, UMR 5822