Suchergebnisse

arXiv:2108.08043v1 ; To study the nuclear (≲1 kpc) dust of nearby (z < 0.1) quasi-stellar objects (QSOs), we obtained new near-infrared (NIR) high angular resolution (∼0farcs3) photometry in the H and Ks bands for 13 QSOs with available mid-infrared (MIR) high angular resolution spectroscopy (∼7.5–13.5 μm). We find that in most QSOs, the NIR emission is unresolved. We subtract the contribution from the accretion disk, which decreases from NIR (∼35%) to MIR (∼2.4%). We also estimate these percentages assuming a bluer accretion disk and find that the contribution in the MIR is nearly seven times larger. We find that the majority of objects (64%, 9/13) are better fitted by the disk+wind H17 model, while others can be fitted by the smooth F06 (14%, 2/13), clumpy N08 (7%, 1/13), clumpy H10 (7%, 1/13), and two-phase media S16 (7%, 1/13) models. However, if we assume the bluer accretion disk, the models fit only 2/13 objects. We measured two NIR-to-MIR spectral indexes, αNIR−MIR(1.6–8.7 μm) and αNIR−MIR(2.2–8.7 μm), and two MIR spectral indexes, αMIR(7.8–9.8 μm) and αMIR(9.8–11.7 μm), from models and observations. From observations, we find that the NIR-to-MIR spectral indexes are ∼−1.1, and the MIR spectral indexes are ∼−0.3. Comparing the synthetic and observed values, we find that none of the models simultaneously match the measured NIR-to-MIR and 7.8–9.8 μm slopes. However, we note that measuring αMIR(7.8–9.8 μm) on the starburst-subtracted Spitzer/IRS spectrum gives values of the slopes (∼−2) that are similar to the synthetic values obtained from the models. ; M.M.-P. acknowledges support from the KASI postdoctoral fellowships. O.G.-M. acknowledges support from the UNAM PAPIIT [IN105720]. I.G.B. acknowledges support from the STFC through grant ST/S000488/1. C.R.A. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (MCIU) under grant RYC-2014–15779, the European Union's Horizon 2020 research and innovation program under Marie Skłodowska-Curie grant agreement No. 860744 (BiD4BESt), and the State Research Agency (AEI-MCINN) of the Spanish MCIU under grants "Feeding and feedback in active galaxies" with reference PID2019–106027GB-C42 and "Quantifying the impact of quasar feedback on galaxy evolution (QSOFEED)" with reference EUR2020–112266. C.R.A. also acknowledges support from the Consejería de Economía, Conocimiento y Empleo del Gobierno de Canarias and the European Regional Development Fund (ERDF) under grant ProID2020010105 and from IAC project P/301404, financed by the Ministry of Science and Innovation through the State Budget and by the Canary Islands Department of Economy, Knowledge and Employment through the Regional Budget of the Autonomous Community. A.A.-H. acknowledges support from PGC2018-094671-B-I00 (MCIU/AEI/FEDER,UE). A.A.-H.'s work was done under project No. MDM-2017-0737 Unidad de Excelencia "María de Maeztu"- Centro de Astrobiología (INTA-CSIC). I.A. acknowledges support from project CB2016-281948. J.M. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709) and research projects AYA2016-76682-C3-1-P (AEI/FEDER, UE) and PID2019-106027GB-C41 (AEI/FEDER, UE). ; Peer reviewed