| Autor: |
Stepney, Matthew, Banerji, Manda, Tang, Shenli, Hewett, Paul C, Temple, Matthew J, Wethers, Clare F, Puglisi, Annagrazia, Molyneux, Stephen J |
| Předmět: |
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| Zdroj: |
Monthly Notices of the Royal Astronomical Society; 9/30/2024, Vol. 533 Issue 3, p2948-2965, 18p |
| Abstrakt: |
We present a deep X-Shooter rest-frame ultraviolet (UV) to optical spectral analysis of the heavily reddened quasar, ULASJ2315+0143 at |$z=2.566$| , known to reside in a major-merger host galaxy. The rest-frame optical is best fit by a dust-reddened quasar (E (B – V) |$^{\rm QSO}= 1.55$|) with black-hole mass |$\rm log_{10}(H\beta , M{\small BH} [{\rm M}_{\odot }]) = 10.26 \pm 0.05$| , bolometric luminosity |$\rm L_{Bol}$| = |$\rm 10^{48.16}\, erg\,\,s^{-1}$| and Eddington-scaled accretion rate log |$_{10}(\rm \lambda _{Edd}) = -0.19$|. We find remarkable similarities between ULASJ2315+0143 and the high-redshift little red dots (LRDs). The rest-frame UV cannot be explained by a dusty quasar component alone and requires an additional blue component consistent with either a star-forming host galaxy or scattered AGN light. We detect broad high-ionization emission lines in the rest-UV, supporting the scattered light interpretation for the UV excess. The scattering fraction represents just 0.05 per cent of the total luminosity of ULASJ2315+0143 . Analysis of the mid-infrared SED suggests an absence of hot dust on torus-scales similar to what is observed for LRDs. The obscuring medium is therefore likely on galaxy scales. We detect narrow, blueshifted associated absorption-line systems in C iv , N v , Si iv , and Si iii. There is evidence for significant high-velocity (>1000 |$\rm km\, s^{-1}$|) outflows in both the broad- and narrow-line regions as traced by C iv and [O iii ] emission. The kinetic power of the [O iii ] wind is |$\dot{\epsilon }_{k}^{ion} = 10^{44.61} \rm erg\, s^{-1} \sim 0.001\, L_{Bol}$|. ULASJ2315+0143 is likely in an important transition phase where star formation, black-hole accretion and multiphase gas flows are simultaneously occurring. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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