In this study, we investigate the X-ray properties of WISE J090924.01+000211.1 (WISEJ0909+0002), an extremely luminous infrared (IR) galaxy (ELIRG) at zspec = 1.871 in the eROSITA Final Equatorial-Depth Survey. WISEJ0909+0002 is a WISE 22 μm source, located in the GAMA-09 field, which was detected by eROSITA during the performance and verification phase. The corresponding optical spectrum indicates that this object is a type-1 active galactic nucleus (AGN). Observations from eROSITA combined with Chandra and XMM-Newton archival data indicate a very luminous (L (2-10 keV) = (2.1 ± 0.2) × 1045 erg s−1) unobscured AGN with a power-law photon index of Γ=1.73−0.15+0.16 and an absorption hydrogen column density of log (NH∕cm−2) < 21.0. The IR luminosity was estimated to be LIR = (1.79 ± 0.09) × 1014 L⊙ from spectral energy distribution modeling based on 22 photometric data points (X-ray to far-IR) with X-CIGALE, which confirmed that WISEJ0909+0002 is an ELIRG. A remarkably high LIR despite very low NH would indicate that we are witnessing a short-lived phase in which hydrogen gas along the line of sight is blown outward, whereas warm and hot dust heated by AGNs still exists. As a consequence of the eROSITA All-Sky Survey, 6.8−5.6+16 × 102 such X-ray-bright ELIRGs are expected to be discovered in the entire extragalactic sky (|b| > 10°). This can potentially be the key population to constrain the bright end of IR luminosity functions.

The eROSITA Final Equatorial-Depth Survey (eFEDS). An X-ray-bright, extremely luminous infrared galaxy at z = 1.87

Brusa Marcella;
2021

Abstract

In this study, we investigate the X-ray properties of WISE J090924.01+000211.1 (WISEJ0909+0002), an extremely luminous infrared (IR) galaxy (ELIRG) at zspec = 1.871 in the eROSITA Final Equatorial-Depth Survey. WISEJ0909+0002 is a WISE 22 μm source, located in the GAMA-09 field, which was detected by eROSITA during the performance and verification phase. The corresponding optical spectrum indicates that this object is a type-1 active galactic nucleus (AGN). Observations from eROSITA combined with Chandra and XMM-Newton archival data indicate a very luminous (L (2-10 keV) = (2.1 ± 0.2) × 1045 erg s−1) unobscured AGN with a power-law photon index of Γ=1.73−0.15+0.16 and an absorption hydrogen column density of log (NH∕cm−2) < 21.0. The IR luminosity was estimated to be LIR = (1.79 ± 0.09) × 1014 L⊙ from spectral energy distribution modeling based on 22 photometric data points (X-ray to far-IR) with X-CIGALE, which confirmed that WISEJ0909+0002 is an ELIRG. A remarkably high LIR despite very low NH would indicate that we are witnessing a short-lived phase in which hydrogen gas along the line of sight is blown outward, whereas warm and hot dust heated by AGNs still exists. As a consequence of the eROSITA All-Sky Survey, 6.8−5.6+16 × 102 such X-ray-bright ELIRGs are expected to be discovered in the entire extragalactic sky (|b| > 10°). This can potentially be the key population to constrain the bright end of IR luminosity functions.
Toba Yoshiki, Brusa Marcella, Liu Teng, Buchner Johannes, Terashima Yuichi, Urrutia Tanya, Salvato Mara, Akiyama Masayuki, Arcodia Riccardo, Goulding,y D., Higuchi Yuichi, Inoue Kaiki T., Kawaguchi Toshihiro, Lamer Georg, Merloni,rea, Nagao Tohru, Ueda Yoshihiro, Nandra Kirpal
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Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11585/858677
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