We present the X-ray spectra of 185 bright sources detected in the XMM-Newton deep survey of the Chandra Deep Field South with the three EPIC cameras combined. The 2–10 keV flux limit of the sample is 2 × 10−15 erg s−1 cm−2. The sources are distributed over a redshift range of z = 0.1−3.8, with 11 new X-ray redshift measurements included. A spectral analysis was performed using a simple model to obtain absorbing column densities, rest-frame 2–10 keV luminosities, and Fe K line properties of 180 sources at z >  0.4. Obscured AGN are found to be more abundant toward higher redshifts. Using the XMM-Newton data alone, seven Compton-thick AGN candidates were identified, which set the Compton-thick AGN fraction at ≃4%. An exploratory spectral inspection method with two rest-frame X-ray colours and an Fe line strength indicator was introduced and tested against the results from spectral fitting. This method works reasonably well to characterise a spectral shape and can be useful for a pre-selection of Compton-thick AGN candidates. We found six objects exhibiting broad Fe K lines out of 21 unobscured AGN of best data quality, implying a detection rate of ∼30%. Five redshift spikes, each with more than six sources, are identified in the redshift distribution of the X-ray sources. Contrary to the overall trend, the sources at the two higher redshift spikes, at z = 1.61 and z = 2.57, exhibit a puzzlingly low obscuration.

Iwasawa K., Comastri A., Vignali C., Gilli R., Lanzuisi G., Brandt W.N., et al. (2020). The XMM deep survey in the CDFS: XI. X-ray spectral properties of 185 bright sources. ASTRONOMY & ASTROPHYSICS, 639, 1-26 [10.1051/0004-6361/201937246].

The XMM deep survey in the CDFS: XI. X-ray spectral properties of 185 bright sources

Vignali C.
Membro del Collaboration Group
;
Brusa M.
Membro del Collaboration Group
;
2020

Abstract

We present the X-ray spectra of 185 bright sources detected in the XMM-Newton deep survey of the Chandra Deep Field South with the three EPIC cameras combined. The 2–10 keV flux limit of the sample is 2 × 10−15 erg s−1 cm−2. The sources are distributed over a redshift range of z = 0.1−3.8, with 11 new X-ray redshift measurements included. A spectral analysis was performed using a simple model to obtain absorbing column densities, rest-frame 2–10 keV luminosities, and Fe K line properties of 180 sources at z >  0.4. Obscured AGN are found to be more abundant toward higher redshifts. Using the XMM-Newton data alone, seven Compton-thick AGN candidates were identified, which set the Compton-thick AGN fraction at ≃4%. An exploratory spectral inspection method with two rest-frame X-ray colours and an Fe line strength indicator was introduced and tested against the results from spectral fitting. This method works reasonably well to characterise a spectral shape and can be useful for a pre-selection of Compton-thick AGN candidates. We found six objects exhibiting broad Fe K lines out of 21 unobscured AGN of best data quality, implying a detection rate of ∼30%. Five redshift spikes, each with more than six sources, are identified in the redshift distribution of the X-ray sources. Contrary to the overall trend, the sources at the two higher redshift spikes, at z = 1.61 and z = 2.57, exhibit a puzzlingly low obscuration.
2020
Iwasawa K., Comastri A., Vignali C., Gilli R., Lanzuisi G., Brandt W.N., et al. (2020). The XMM deep survey in the CDFS: XI. X-ray spectral properties of 185 bright sources. ASTRONOMY & ASTROPHYSICS, 639, 1-26 [10.1051/0004-6361/201937246].
Iwasawa K.; Comastri A.; Vignali C.; Gilli R.; Lanzuisi G.; Brandt W.N.; Tozzi P.; Brusa M.; Carrera F.J.; Ranalli P.; Mainieri V.; Georgantopoulos I....espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/808863
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