Redshift identification of X-ray-selected active galactic nuclei in the J1030 field: searching for large-scale structures and high-redshift sources

We publicly release the spectroscopic and photometric redshift catalog of the sources detected with Chandra in the field of the z = 6.3 quasar SDSS J1030+0525. This is currently the fifth-deepest extragalactic X-ray field, and reaches a 0.5 2 keV flux limit of f0:5-2 = 6 × 10-17 erg s-1 cm-2. Using...

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Detalhes bibliográficos
Autores: Marchesi, Stefano, Mignoli, Marco, Gilli, Roberto, Peca, Alessandro, Bolzonella, M., Nanni, R., Annunziatella, M., Balmaverde, Barbara, Brusa, Marcella, Calura, Francesco, Cassarà, L. P., Chiaberge, Marco, Comastri, Andrea, Cusano, F., D'Amato, Quirino, Iwasawa, Kazushi, Lanzuisi, Giorgio, Marchesini, D., Morishita, Takahiro, Prandoni, Isabella, Rossi, A., Tozzi, A., Vignali, Cristian, Vito, Fabio, Zamorani, G., Norman, Colin
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2021
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositório:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/261455
Acesso em linha:http://hdl.handle.net/10261/261455
Access Level:Acceso aberto
Palavra-chave:Galaxies: Seyfert
Large-scale structure of the universe
Galaxies: high-redshift
Quasars: supermassive black holes
X-ray galaxies
Descrição
Resumo:We publicly release the spectroscopic and photometric redshift catalog of the sources detected with Chandra in the field of the z = 6.3 quasar SDSS J1030+0525. This is currently the fifth-deepest extragalactic X-ray field, and reaches a 0.5 2 keV flux limit of f0:5-2 = 6 × 10-17 erg s-1 cm-2. Using two independent methods, we measure a photometric redshift for 243 objects, while 123 (51%) sources also have a spectroscopic redshift, 110 of which come from an INAF-Large Binocular Telescope (LBT) Strategic Program.We use the spectroscopic redshifts to determine the quality of the photometric ones, and find it to be in agreement with that of other X-ray surveys which used a similar number of photometric data points. In particular, we measure a sample normalized median absolute deviation of NMAD = 1.48 × median(||zphot - zspec||/(1 + zspec)) = 0.065. We use these new spectroscopic and photometric redshifts to study the properties of the Chandra J1030 field.We observe several peaks in our spectroscopic redshift distribution between z = 0.15 and z = 1.5, and find that the sources in each peak are often distributed across the whole Chandra field of view. This confirms that X-ray-selected AGNs can efficiently track large-scale structures over physical scales of several megaparsecs. Finally, we computed the Chandra J1030 z > 3 number counts: while the spectroscopic completeness of our sample is limited at high redshift, our results point towards a potential source excess at z ≥ 4, which we plan to either confirm or reject in the near future with dedicated spectroscopic campaigns.