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arXiv · 2206.15347

Warm molecular and ionized gas kinematics in the Type-2 quasar J0945+1737

G. Speranza·C. Ramos Almeida·J. A. Acosta-Pulido·R. A. Riffel·C. Tadhunter·J. C. S. Pierce·A. Rodríguez-Ardila·M. Coloma Puga·M. Brusa·B. Musiimenta·D. M. Alexander·A. Lapi·F. Shankar·C. Villforth
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Abstract

We analyze Near-Infrared Integral Field Spectrograph (NIFS) observations of the type-2 quasar (QSO2) SDSS J094521.33+173753.2 to investigate its warm molecular and ionized gas kinematics. This QSO2 has a bolometric luminosity of 10$^{45.7}$ erg s$^{-1}$ and a redshift of z = 0.128. The K-band spectra provided by NIFS cover a range of 1.99-2.40 $\mu$m where low-ionization (Pa$\alpha$ and Br$\delta$), high ionization ([S XI]$\lambda$1.920 $\mu$m and [Si~VI]$\lambda$1.963 $\mu$m) and warm molecular lines (from H$_2$ 1-0S(5) to 1-0S(1)) are detected, allowing us to study the multi-phase gas kinematics. Our analysis reveals gas in ordinary rotation in all the emission lines detected and also outflowing gas in the case of the low- and high-ionization emission lines. In the case of the nuclear spectrum, which corresponds to a circular aperture of 0.3\arcsec~(686 pc) in diameter, the warm molecular lines can be characterized using a single Gaussian component of full width at half maximum (FWHM)= 350-400 km s$^{-1}$, while Pa$\alpha$, Br$\delta$, and [Si~VI] are best fitted with two blue-shifted Gaussian components of FWHM$\sim$800 and 1700 km s$^{-1}$, in addition to a narrow component of $\sim$300 km s$^{-1}$. We interpret the blue-shifted broad components as outflowing gas, which reaches the highest velocities, of up to $-$840 km s$^{-1}$, in the south-east direction (PA$\sim$125$^{\circ}$), extending up to a distance of $\sim$3.4 kpc from the nucleus. The ionized outflow has a maximum mass outflow rate of $\dot{\text{{M}}}_{\text{{out, max}}}$=42-51 M$_\odot$ yr$^{-1}$, and its kinetic power represents 0.1$\%$ of the quasar bolometric luminosity.

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G. Speranza, C. Ramos Almeida, J. A. Acosta-Pulido, R. A. Riffel, C. Tadhunter, J. C. S. Pierce, A. Rodríguez-Ardila, M. Coloma Puga, M. Brusa, B. Musiimenta, D. M. Alexander, A. Lapi, F. Shankar, C. Villforth. 2022-06-30. Warm molecular and ionized gas kinematics in the Type-2 quasar J0945+1737. https://doi.org/10.1051/0004-6361%2F202243585

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