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We quantify the luminosity contribution of active galactic nuclei (AGN) to the 12 $\mu$m, mid-infrared (MIR; 5-38 $\mu$m), and the total IR (5-1000 $\mu$m) emission in the local AGN detected in the all-sky 70-month Swift/Burst Alert Telescope (BAT) ultra hard X-ray survey. We decompose the IR spectral energy distributions (SEDs) of 587 objects into AGN and starburst components using AGN torus and star-forming galaxy templates. This enables us to recover the AGN torus emission also for low-luminosity end, down to $\log (L_{14-150}/{\rm erg}~{\rm s}^{-1}) \simeq 41$, which typically have significant host galaxy contamination. We find that the luminosity contribution of the AGN to the 12 $\mu$m, the MIR, and the total IR band is an increasing function of the 14-150 keV luminosity. We also find that for the most extreme cases, the IR pure-AGN emission from the torus can extend up to 90 $\mu$m. The obtained total IR AGN luminosity through the IR SED decomposition enables us to estimate the fraction of the sky obscured by dust, i.e., the dust covering factor. We demonstrate that the median of the dust covering factor is always smaller than that of the X-ray obscuration fraction above the AGN bolometric luminosity of $\log (L_{\rm bol}/{\rm erg}~{\rm s}^{-1}) \simeq 42.5$. Considering that X-ray obscuration fraction is equivalent to the covering factor coming from both the dust and gas, it indicates that an additional neutral gas component, along with the dusty torus, is responsible for the absorption of X-ray emission., Comment: 21 pages, 15 figures, accepted for publication in ApJ. The full list of Table 1 is available at http://www.kusastro.kyoto-u.ac.jp/~ichikawa/Table1_MR_20181107.txt

We present arcsecond-scale observations of the active galactic nuclei (AGNs) of seven nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the 31.5 and 37.1 um filters of the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We isolate unresolved emission from the torus and find extended diffuse emission in six 37.1 um residual images in our sample. Using Spitzer/IRS spectra, we determine the dominant mid-infrared (MIR) extended emission source and attribute it to dust in the narrow line region (NLR) or star formation. We compare the optical NLR and radio jet axes to the extended 37.1 um emission and find coincident axes for three sources. For those AGNs with extended emission coincident with the optical axis, we find that spatial scales of the residual images are consistent with 0.1 - 1 kpc scale distances to which dust can be heated by the AGN. Using previously published subarcsecond 1 - 20 um imaging and spectroscopic data along with our new observations, we construct broadband spectral energy distributions (SEDs) of the AGNs at wavelengths 1 - 40 um. We find that three AGNs in our sample tentatively show a turnover in the SED between 30 - 40 um. Using results from Clumpy torus models and the Bayesian inference tool BayesClumpy, we find that the posterior outputs for AGNs with MIR turnover revealed by SOFIA/FORCAST have smaller uncertainties than AGNs that do not show a turnover., Comment: 16 pages, 9 figures

We present observations of NGC 1068 covering the $19.7-53.0$ $\mu$m wavelength range using FORCAST and HAWC+ onboard SOFIA. Using these observations, high-angular resolution infrared (IR) and sub-mm observations, we find an observational turn-over of the torus emission in the $30-40$ $\mu$m wavelength range with a characteristic temperature of $70-100$ K. This component is clearly different from the diffuse extended emission in the narrow line and star formation regions at 10-100 $\mu$m within the central 700 pc. We compute $2.2-432$ $\mu$m 2D images using the best inferred \textsc{clumpy} torus model based on several nuclear spectral energy distribution (SED) coverages. We find that when $1-20$ $\mu$m SED is used, the inferred result gives a small torus size ($<4$ pc radius) and a steep radial dust distribution. The computed torus using the $1-432$ $\mu$m SED provides comparable torus sizes, $5.1^{+0.4}_{-0.4}$ pc radius, and morphology to the recently resolved 432 $\mu$m ALMA observations. This result indicates that the $1-20$ $\mu$m wavelength range is not able to probe the full extent of the torus. The characterization of the turn-over emission of the torus using the $30-60$ $\mu$m wavelength range is sensitive to the detection of cold dust in the torus. The morphology of the dust emission in our 2D image at 432 $\mu$m is spatially coincident with the cloud distribution, while the morphology of the emission in the $1-20$ $\mu$m wavelength range shows an elongated morphology perpendicular to the cloud distribution. We find that our 2D \textsc{clumpy} torus image at 12 $\mu$m can produce comparable results to those observed using IR interferometry., Comment: 12 pages, 7 Figures, Accepted for publication in ApJ

We present arcsecond-scale observations of the active galactic nuclei (AGNs) of seven nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the 31.5 and 37.1 um filters of the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We isolate unresolved emission from the torus and find extended diffuse emission in six 37.1 um residual images in our sample. Using Spitzer/IRS spectra, we determine the dominant mid-infrared (MIR) extended emission source and attribute it to dust in the narrow line region (NLR) or star formation. We compare the optical NLR and radio jet axes to the extended 37.1 um emission and find coincident axes for three sources. For those AGNs with extended emission coincident with the optical axis, we find that spatial scales of the residual images are consistent with 0.1 - 1 kpc scale distances to which dust can be heated by the AGN. Using previously published subarcsecond 1 - 20 um imaging and spectroscopic data along with our new observations, we construct broadband spectral energy distributions (SEDs) of the AGNs at wavelengths 1 - 40 um. We find that three AGNs in our sample tentatively show a turnover in the SED between 30 - 40 um. Using results from Clumpy torus models and the Bayesian inference tool BayesClumpy, we find that the posterior outputs for AGNs with MIR turnover revealed by SOFIA/FORCAST have smaller uncertainties than AGNs that do not show a turnover., Comment: 16 pages, 9 figures

We quantify the luminosity contribution of active galactic nuclei (AGN) to the 12 $\mu$m, mid-infrared (MIR; 5-38 $\mu$m), and the total IR (5-1000 $\mu$m) emission in the local AGN detected in the all-sky 70-month Swift/Burst Alert Telescope (BAT) ultra hard X-ray survey. We decompose the IR spectral energy distributions (SEDs) of 587 objects into AGN and starburst components using AGN torus and star-forming galaxy templates. This enables us to recover the AGN torus emission also for low-luminosity end, down to $\log (L_{14-150}/{\rm erg}~{\rm s}^{-1}) \simeq 41$, which typically have significant host galaxy contamination. We find that the luminosity contribution of the AGN to the 12 $\mu$m, the MIR, and the total IR band is an increasing function of the 14-150 keV luminosity. We also find that for the most extreme cases, the IR pure-AGN emission from the torus can extend up to 90 $\mu$m. The obtained total IR AGN luminosity through the IR SED decomposition enables us to estimate the fraction of the sky obscured by dust, i.e., the dust covering factor. We demonstrate that the median of the dust covering factor is always smaller than that of the X-ray obscuration fraction above the AGN bolometric luminosity of $\log (L_{\rm bol}/{\rm erg}~{\rm s}^{-1}) \simeq 42.5$. Considering that X-ray obscuration fraction is equivalent to the covering factor coming from both the dust and gas, it indicates that an additional neutral gas component, along with the dusty torus, is responsible for the absorption of X-ray emission., Comment: 21 pages, 15 figures, accepted for publication in ApJ. The full list of Table 1 is available at http://www.kusastro.kyoto-u.ac.jp/~ichikawa/Table1_MR_20181107.txt

We present observations of NGC 1068 covering the $19.7-53.0$ $\mu$m wavelength range using FORCAST and HAWC+ onboard SOFIA. Using these observations, high-angular resolution infrared (IR) and sub-mm observations, we find an observational turn-over of the torus emission in the $30-40$ $\mu$m wavelength range with a characteristic temperature of $70-100$ K. This component is clearly different from the diffuse extended emission in the narrow line and star formation regions at 10-100 $\mu$m within the central 700 pc. We compute $2.2-432$ $\mu$m 2D images using the best inferred \textsc{clumpy} torus model based on several nuclear spectral energy distribution (SED) coverages. We find that when $1-20$ $\mu$m SED is used, the inferred result gives a small torus size ($<4$ pc radius) and a steep radial dust distribution. The computed torus using the $1-432$ $\mu$m SED provides comparable torus sizes, $5.1^{+0.4}_{-0.4}$ pc radius, and morphology to the recently resolved 432 $\mu$m ALMA observations. This result indicates that the $1-20$ $\mu$m wavelength range is not able to probe the full extent of the torus. The characterization of the turn-over emission of the torus using the $30-60$ $\mu$m wavelength range is sensitive to the detection of cold dust in the torus. The morphology of the dust emission in our 2D image at 432 $\mu$m is spatially coincident with the cloud distribution, while the morphology of the emission in the $1-20$ $\mu$m wavelength range shows an elongated morphology perpendicular to the cloud distribution. We find that our 2D \textsc{clumpy} torus image at 12 $\mu$m can produce comparable results to those observed using IR interferometry., Comment: 12 pages, 7 Figures, Accepted for publication in ApJ

We present 31.5 micron imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively detect extended 31 micron emission for the first time in our sample. In combination with this new data set, subarcsecond resolution 1-18 micron imaging and 7.5-13 micron spectroscopic observations were used to compute the nuclear spectral energy distribution (SED) of each galaxy. We found that the turnover of the torus emission does not occur at wavelengths <31.5 micron, which we interpret as a lower-limit for the wavelength of peak emission. We used CLUMPY torus models to fit the nuclear infrared (IR) SED and infer trends in the physical parameters of the AGN torus for the galaxies in the sample. Including the 31.5 micron nuclear flux in the SED 1) reduces the number of clumpy torus models compatible with the data, and 2) modifies the model output for the outer radial extent of the torus for 10 of the 11 objects. Specifically, six (60%) objects show a decrease in radial extent while four (40%) show an increase. We find torus outer radii ranging from <1pc to 8.4 pc, Comment: 15 pages, 7 figures. Accepted for publication in MNRAS

We present 31.5 micron imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively detect extended 31 micron emission for the first time in our sample. In combination with this new data set, subarcsecond resolution 1-18 micron imaging and 7.5-13 micron spectroscopic observations were used to compute the nuclear spectral energy distribution (SED) of each galaxy. We found that the turnover of the torus emission does not occur at wavelengths <31.5 micron, which we interpret as a lower-limit for the wavelength of peak emission. We used CLUMPY torus models to fit the nuclear infrared (IR) SED and infer trends in the physical parameters of the AGN torus for the galaxies in the sample. Including the 31.5 micron nuclear flux in the SED 1) reduces the number of clumpy torus models compatible with the data, and 2) modifies the model output for the outer radial extent of the torus for 10 of the 11 objects. Specifically, six (60%) objects show a decrease in radial extent while four (40%) show an increase. We find torus outer radii ranging from <1pc to 8.4 pc, Comment: 15 pages, 7 figures. Accepted for publication in MNRAS

We report on extensive testing carried out on the optical fibers for the VIRUS instrument. The primary result of this work explores how 10+ years of simulated wear on a VIRUS fiber bundle affects both transmission and focal ratio degradation (FRD) of the optical fibers. During the accelerated lifetime tests we continuously monitored the fibers for signs of FRD. We find that transient FRD events were common during the portions of the tests when motion was at telescope slew rates, but dropped to negligible levels during rates of motion typical for science observation. Tests of fiber transmission and FRD conducted both before and after the lifetime tests reveal that while transmission values do not change over the 10+ years of simulated wear, a clear increase in FRD is seen in all 18 fibers tested. This increase in FRD is likely due to microfractures that develop over time from repeated flexure of the fiber bundle, and stands in contrast to the transient FRD events that stem from localized stress and subsequent modal diffusion of light within the fibers. There was no measurable wavelength dependence on the increase in FRD over 350 nm to 600 nm. We also report on bend radius tests conducted on individual fibers and find the 266 microns VIRUS fibers to be immune to bending-induced FRD at bend radii of R > 10cm. Below this bend radius FRD increases slightly with decreasing radius. Lastly, we give details of a degradation seen in the fiber bundle currently deployed on the Mitchell Spectrograph (formally VIRUS-P) at McDonald Observatory. The degradation is shown to be caused by a localized shear in a select number of optical fibers that leads to an explosive form of FRD. In a few fibers, the overall transmission loss through the instrument can exceed 80%., Comment: 19 pages, 22 figures

We report on extensive testing carried out on the optical fibers for the VIRUS instrument. The primary result of this work explores how 10+ years of simulated wear on a VIRUS fiber bundle affects both transmission and focal ratio degradation (FRD) of the optical fibers. During the accelerated lifetime tests we continuously monitored the fibers for signs of FRD. We find that transient FRD events were common during the portions of the tests when motion was at telescope slew rates, but dropped to negligible levels during rates of motion typical for science observation. Tests of fiber transmission and FRD conducted both before and after the lifetime tests reveal that while transmission values do not change over the 10+ years of simulated wear, a clear increase in FRD is seen in all 18 fibers tested. This increase in FRD is likely due to microfractures that develop over time from repeated flexure of the fiber bundle, and stands in contrast to the transient FRD events that stem from localized stress and subsequent modal diffusion of light within the fibers. There was no measurable wavelength dependence on the increase in FRD over 350 nm to 600 nm. We also report on bend radius tests conducted on individual fibers and find the 266 microns VIRUS fibers to be immune to bending-induced FRD at bend radii of R > 10cm. Below this bend radius FRD increases slightly with decreasing radius. Lastly, we give details of a degradation seen in the fiber bundle currently deployed on the Mitchell Spectrograph (formally VIRUS-P) at McDonald Observatory. The degradation is shown to be caused by a localized shear in a select number of optical fibers that leads to an explosive form of FRD. In a few fibers, the overall transmission loss through the instrument can exceed 80%., Comment: 19 pages, 22 figures