Medium-resolution Optical and Near-Infrared Spectral Atlas of 16 2MASS-selected NIR-red Active Galactic Nuclei at $z sim 0.3$. (arXiv:1812.06991v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Kim_D/0/1/0/all/0/1">Dohyeong Kim</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Im_M/0/1/0/all/0/1">Myungshin Im</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Canalizo_G/0/1/0/all/0/1">Gabriela Canalizo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kim_M/0/1/0/all/0/1">Minjin Kim</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kim_J/0/1/0/all/0/1">Ji Hoon Kim</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Woo_J/0/1/0/all/0/1">Jong-Hak Woo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Taak_Y/0/1/0/all/0/1">Yoon Chan Taak</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kim_J/0/1/0/all/0/1">Jae-Woo Kim</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lazarova_M/0/1/0/all/0/1">Mariana Lazarova</a>

We present medium-resolution spectra ($R sim 2000$–4000) at
0.4–1.0,$mu$m and 0.7–2.5,$mu$m of 16 active galactic nuclei (AGNs)
selected with red color in the near-infrared (NIR) of $J – K > 2.0$ mag at $z
sim 0.3$. We fit the H$beta$, H$alpha$, P$beta$, and P$alpha$ lines from
these spectra to obtain their luminosities and line widths. We derive the
$E(B-V)$ color excess values of the NIR-red AGNs using two methods, one based
on the line-luminosity ratios and another based on the continuum slopes. The
two $E(B-V)$ values agree with each other at rms dispersion $sim$ 0.249. About
half of the NIR-red AGNs have $g’-K < 5$ magnitude, and we find that these NIR red, but blue in optical-NIR AGNs, have $E(B-V) sim 0$, suggesting that a significant fraction of the NIR color-selected red AGNs are unobscured or only mildly obscured. After correcting for the dust extinction, we estimate the black hole (BH) masses and the bolometric luminosities of the NIR-red AGNs using the Paschen lines to calculate their Eddington ratios ($lambda_{rm Edd}$). The median Eddington ratios of nine NIR-red AGNs ($log (lambda_{rm Edd}) simeq -0.654 pm 0.176$) are only mildly higher than those of unobscured type 1 AGNs ($log (lambda_{rm Edd}) simeq -0.961 pm 0.008$). Moreover, we find that the $M_{rm BH}$--$sigma_{ast}$ relation for three NIR-red AGNs is consistent with that of unobscured type 1 AGNs at similar redshift. These results suggest that the NIR red color selection alone is not effective at picking up dusty, intermediate-stage AGNs.

We present medium-resolution spectra ($R sim 2000$–4000) at
0.4–1.0,$mu$m and 0.7–2.5,$mu$m of 16 active galactic nuclei (AGNs)
selected with red color in the near-infrared (NIR) of $J – K > 2.0$ mag at $z
sim 0.3$. We fit the H$beta$, H$alpha$, P$beta$, and P$alpha$ lines from
these spectra to obtain their luminosities and line widths. We derive the
$E(B-V)$ color excess values of the NIR-red AGNs using two methods, one based
on the line-luminosity ratios and another based on the continuum slopes. The
two $E(B-V)$ values agree with each other at rms dispersion $sim$ 0.249. About
half of the NIR-red AGNs have $g’-K < 5$ magnitude, and we find that these NIR
red, but blue in optical-NIR AGNs, have $E(B-V) sim 0$, suggesting that a
significant fraction of the NIR color-selected red AGNs are unobscured or only
mildly obscured. After correcting for the dust extinction, we estimate the
black hole (BH) masses and the bolometric luminosities of the NIR-red AGNs
using the Paschen lines to calculate their Eddington ratios ($lambda_{rm
Edd}$). The median Eddington ratios of nine NIR-red AGNs ($log (lambda_{rm
Edd}) simeq -0.654 pm 0.176$) are only mildly higher than those of unobscured
type 1 AGNs ($log (lambda_{rm Edd}) simeq -0.961 pm 0.008$). Moreover, we
find that the $M_{rm BH}$–$sigma_{ast}$ relation for three NIR-red AGNs is
consistent with that of unobscured type 1 AGNs at similar redshift. These
results suggest that the NIR red color selection alone is not effective at
picking up dusty, intermediate-stage AGNs.

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