Euclid preparation. XLIX. Selecting active galactic nuclei using observed colours

arXiv (Cornell University)

Abstract

Euclid will cover over 14000 $deg^{2}$ with two optical and near-infrared spectro-photometric instruments, and is expected to detect around ten million active galactic nuclei (AGN). This unique data set will make a considerable impact on our understanding of galaxy evolution and AGN. In this work we identify the best colour selection criteria for AGN, based only on Euclid photometry or including ancillary photometric observations, such as the data that will be available with the Rubin legacy survey of space and time (LSST) and observations already available from Spitzer/IRAC. The analysis is performed for unobscured AGN, obscured AGN, and composite (AGN and star-forming) objects. We make use of the spectro-photometric realisations of infrared-selected targets at all-z (SPRITZ) to create mock catalogues mimicking both the Euclid Wide Survey (EWS) and the Euclid Deep Survey (EDS). Using these catalogues we estimate the best colour selection, maximising the harmonic mean (F1) of completeness and purity. The selection of unobscured AGN in both Euclid surveys is possible with Euclid photometry alone with F1=0.22-0.23, which can increase to F1=0.43-0.38 if we limit at z>0.7. Such selection is improved once the Rubin/LSST filters (a combination of the u, g, r, or z filters) are considered, reaching F1=0.84 and 0.86 for the EDS and EWS, respectively. The combination of a Euclid colour with the [3.6]-[4.5] colour, which is possible only in the EDS, results in an F1-score of 0.59, improving the results using only Euclid filters, but worse than the selection combining Euclid and LSST. The selection of composite ($f_{\rm AGN}$=0.05-0.65 at 8-40 $μm$) and obscured AGN is challenging, with F1<0.3 even when including ancillary data. This is driven by the similarities between the broad-band spectral energy distribution of these AGN and star-forming galaxies in the wavelength range 0.3-5 $μm$.

Authors 98

1. Euclid Collaboration
2. M. Massimo

   University of Bologna

   Affiliation as printed

   Dipartimento di Fisica e Astronomia , Università di Bologna , Via Gobetti 93/2 , 40129 Bologna , Italy

3. S. Fotopoulou

   University of Bristol

   Affiliation as printed

   School of Physics , HH Wills Physics Laboratory , University of Bristol , Tyndall Avenue , Bristol , BS8 1TL , UK

4. V. Allevato

   Astronomical Observatory of Capodimonte

   Affiliation as printed

   INAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16 , 80131 Napoli , Italy

5. M. Bolzonella

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

   Affiliation as printed

   INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

6. Carlotta Gruppioni

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

   Affiliation as printed

   INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

7. Lucia Pozzetti

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

   Affiliation as printed

   INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

8. Giulia Rodighiero

   University of Padua · Osservatorio Astronomico di Padova

   Affiliation as printed

   Dipartimento di Fisica e Astronomia "G. Galilei" , Università di Padova , Via Marzolo 8 , 35131 Padova , Italy

   INAF-Osservatorio Astronomico di Padova , Via dell'Osservatorio 5 , 35122 Padova , Italy

9. Stephen Serjeant

   The Open University

   Affiliation as printed

   School of Physical Sciences , The Open University , Milton Keynes , MK7 6AA , UK

10. P. A. C. Cunha

    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 , Rua do Campo de Alegre , 4150-007 Porto , Portugal

    Instituto de Astrofísica e Ciências do Espaço , Universidade do Porto , CAUP , Rua das Estrelas , PT4150-762 Porto , Portugal

11. L. Gabarra
12. A. Feltre

    Arcetri Astrophysical Observatory · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Arcetri , Largo E. Fermi 5 , 50125 , Firenze , Italy

13. A. Humphrey

    Universidade do Porto · Institute of Astrophysics and Space Sciences · Centro de Astrofísica da Universidade do Porto · DTX Digital Transformation CoLAB

    Affiliation as printed

    DTx -Digital Transformation CoLAB , Building 1 ,

    Instituto de Astrofísica e Ciências do Espaço , Universidade do Porto , CAUP , Rua das Estrelas , PT4150-762 Porto , Portugal

14. Fabio La Franca
15. Hermine Landt

    Durham University

    Affiliation as printed

    Department of Physics , Centre for Extragalactic Astronomy , Durham University , South Road , DH1 3LE , UK

16. Filippo Mannucci

    Arcetri Astrophysical Observatory · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Arcetri , Largo E. Fermi 5 , 50125 , Firenze , Italy

17. Isabella Prandoni

    Istituto di Radioastronomia di Bologna

    Affiliation as printed

    INAF , Istituto di Radioastronomia , Via Piero Gobetti 101 , 40129 Bologna , Italy

18. M. Radovich

    Osservatorio Astronomico di Padova

    Affiliation as printed

    INAF-Osservatorio Astronomico di Padova , Via dell'Osservatorio 5 , 35122 Padova , Italy

19. Federica Ricci

    Roma Tre University · Astronomical Observatory of Rome · National Institute for Astrophysics

    Affiliation as printed

    Department of Mathematics and Physics , Roma Tre University , Via della Vasca Navale 84 , 00146 Rome , Italy

    INAF-Osservatorio Astronomico di Roma , Via Frascati 33 , 00078 Monteporzio Catone , Italy

20. M. Salvato

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max Planck Institute for Extraterrestrial Physics , Giessenbachstr. 1 , 85748 Garching , Germany

21. F. Shankar

    University of Southampton

    Affiliation as printed

    Department of Physics and Astronomy , University of Southampton , Southampton , SO17 1BJ , UK

22. D. Stern

    California Institute of Technology · Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory , California Institute of Technology , 4800 Oak Grove Drive , Pasadena , CA , 91109 , USA

23. Luigi Spinoglio

    Institute for Space Astrophysics and Planetology

    Affiliation as printed

    INAF-Istituto di Astrofisica e Planetologia Spaziali , via del Fosso del Cavaliere , 100 , 00100 Roma , Italy

24. Daniela Vergani

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

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

25. C. Vignali

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

    Affiliation as printed

    Dipartimento di Fisica e Astronomia "Augusto Righi " -Alma Mater Studiorum Università di Bologna , via Piero Gobetti 93/2 , 40129 Bologna , Italy

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

26. G. Zamorani

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

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

27. L. Y. Aaron Yung

    Goddard Space Flight Center

    Affiliation as printed

    NASA Goddard Space Flight Center , Greenbelt , MD 20771 , USA

28. S. Charlot

    Centre National de la Recherche Scientifique · Institut d'Astrophysique de Paris · Université Pierre-et-Marie-Curie

    Affiliation as printed

    Sorbonne Universités , UPMC Univ Paris 6 et CNRS , UMR 7095 ,

29. 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 , 91405 , Orsay , France

30. Adam Amara

    University of Portsmouth

    Affiliation as printed

    Institute of Cosmology and Gravitation , University of Portsmouth , Portsmouth PO1 3FX , UK

31. Stefano Andreon

    Brera Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Brera , Via Brera 28 , 20122 Mi- lano , Italy

32. 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 , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

33. Marco Baldi
34. 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 , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

35. Paola Maria Battaglia

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

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

36. Ralf Bender

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

    Affiliation as printed

    Max Planck Institute for Extraterrestrial Physics , Giessenbachstr. 1 , 85748 Garching , Germany

    Universitäts-Sternwarte München , Fakultät für Physik , Ludwig- Maximilians-Universität München , Scheinerstrasse 1 , 81679 München , Germany

37. D. Bonino

    Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino , Via Osservatorio 20 , 10025 Pino Torinese (TO) , Italy

38. E. Branchini Aachen Dipartimento di Fisica

    Université Toulouse III - Paul Sabatier · Istituto Nazionale di Fisica Nucleare, Sezione di Torino · Istituto Nazionale di Fisica Nucleare, Sezione di Genova · Institut de Recherche en Astrophysique et Planétologie · Université de Toulouse · University of Turin · University of Genoa · National Institute for Astrophysics · RWTH Aachen University

    Affiliation as printed

    Dipartimento di Fisica , Università di Genova , Via Dodecaneso 33 , 16146 , Genova , Italy 31 INFN-Sezione di Genova, Via Dodecaneso 33, 16146, Genova, Italy 32 Institut de Recherche en Astrophysique et Planétologie (IRAP), Université de Toulouse, CNRS, UPS, CNES, 14 Av. Edouard Belin, 31400 Toulouse, France 33 Department of Physics "E. Pancini", University Federico II, Via Cinthia 6, 80126, Napoli, Italy 34 Dipartimento di Fisica, Università degli Studi di Torino, Via P. Giuria 1, 10125 Torino, Italy 35 INFN-Sezione di Torino, Via P. Giuria 1, 10125 Torino, Italy 36 INAF-IASF Milano, Via Alfonso Corti 12, 20133 Milano, Italy 37 Institut de Física d'Altes Energies (IFAE), The Barcelona Insti- tute of Science and Technology, Campus UAB, 08193 Bellaterra (Barcelona), Spain 38 Port d'Informació Científica, Campus UAB, C. Albareda s/n, 08193 Bellaterra (Barcelona), Spain 39 Institute for Theoretical Particle Physics and Cosmology (TTK), RWTH Aachen University, 52056 Aachen, Germany 40 Inst

39. S. Brau-Nogue

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

40. M. Brescia

    Astronomical Observatory of Capodimonte

    Affiliation as printed

    INAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16 , 80131 Napoli , Italy

41. S. Camera

    Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino , Via Osservatorio 20 , 10025 Pino Torinese (TO) , Italy

42. V. Capobianco

    Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino , Via Osservatorio 20 , 10025 Pino Torinese (TO) , Italy

43. C. Carbone

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

44. J. Carretero

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

45. Santiago Casas

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

46. Francisco Javier Castander

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

47. M. Castellano

    Astronomical Observatory of Rome · National Institute for Astrophysics

    Affiliation as printed

    INAF-Osservatorio Astronomico di Roma , Via Frascati 33 , 00078 Monteporzio Catone , Italy

48. S. Cavuoti

    Astronomical Observatory of Capodimonte

    Affiliation as printed

    INAF-Osservatorio Astronomico di Capodimonte , Via Moiariello 16 , 80131 Napoli , Italy

49. A. Cimatti

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

50. G. Congedo

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

51. Christopher J. Conselice

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

52. L. Conversi

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

53. Y. Copin

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

54. L. Corcione

    Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino , Via Osservatorio 20 , 10025 Pino Torinese (TO) , Italy

55. F. Courbin

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

56. Hélène M. Courtois

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

57. Mark S. Cropper

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

58. A. Da Silva

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

59. Hubert Degaudenzi

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

60. Anna M. Di Giorgio

    Institute for Space Astrophysics and Planetology

    Affiliation as printed

    INAF-Istituto di Astrofisica e Planetologia Spaziali , via del Fosso del Cavaliere , 100 , 00100 Roma , Italy

61. J. Dinis

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

62. X. Dupac

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

63. S. Dusini

    Istituto Nazionale di Fisica Nucleare, Sezione di Padova

    Affiliation as printed

    INFN-Padova , Via Marzolo 8 , 35131 Padova , Italy

64. A. Ealet

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

65. Maria Farina

    Institute for Space Astrophysics and Planetology

    Affiliation as printed

    INAF-Istituto di Astrofisica e Planetologia Spaziali , via del Fosso del Cavaliere , 100 , 00100 Roma , Italy

66. S. Farrens

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

67. S Ferriol

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

68. M. Frailis

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

69. 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 , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

70. P. Franzetti

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

71. M. Fumana

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

72. Samuele Galeotta

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

73. B. Garilli

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

74. Bryan R. Gillis

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

75. C. Giocoli

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

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy

    INFN-Sezione di Bologna , Viale Berti Pichat 6/2 , 40127 Bologna , Italy

76. B. R. Granett

    Brera Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Brera , Via Brera 28 , 20122 Mi- lano , Italy

77. A. Grazian

    Osservatorio Astronomico di Padova

    Affiliation as printed

    INAF-Osservatorio Astronomico di Padova , Via dell'Osservatorio 5 , 35122 Padova , Italy

78. Frank U. Grupp

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

    Affiliation as printed

    Max Planck Institute for Extraterrestrial Physics , Giessenbachstr. 1 , 85748 Garching , Germany

    Universitäts-Sternwarte München , Fakultät für Physik , Ludwig- Maximilians-Universität München , Scheinerstrasse 1 , 81679 München , Germany

79. L. Guzzo

    Brera Astronomical Observatory

    Affiliation as printed

    INAF-Osservatorio Astronomico di Brera , Via Brera 28 , 20122 Mi- lano , Italy

80. S. V. H. Haugan

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

81. W. Holmes

    California Institute of Technology · Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory , California Institute of Technology , 4800 Oak Grove Drive , Pasadena , CA , 91109 , USA

82. I. Hook

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

83. F. Hormuth

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

84. Allan Hornstrup

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

85. K. Jahnkę

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

86. Elina Keihänen
87. Smaïn Kermiche

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

88. A. Kiessling

    California Institute of Technology · Jet Propulsion Laboratory

    Affiliation as printed

    Jet Propulsion Laboratory , California Institute of Technology , 4800 Oak Grove Drive , Pasadena , CA , 91109 , USA

89. M. Kilbinger

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

90. T. Kitching

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

91. M Kümmel
92. Martin Kunz

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

93. Hannu Kurki-Suonio

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

94. S. Ligori

    Osservatorio Astrofisico di Torino

    Affiliation as printed

    INAF-Osservatorio Astrofisico di Torino , Via Osservatorio 20 , 10025 Pino Torinese (TO) , Italy

95. Per Barth Lilje

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

96. V. Lindholm

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

97. Ivan Lloro

    University of Minho

    Affiliation as printed

    Azurém Cam- pus , University of Minho , 4800-058 Guimarães , Portugal

98. E. Maiorano

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

    Affiliation as printed

    INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna , Via Piero Gobetti 93/3 , 40129 Bologna , Italy