The Dust Sublimation Region of the Type 1 AGN NGC 4151 at a Hundred Microarcsecond Scale as Resolved by the CHARA Array Interferometer
| العنوان: | The Dust Sublimation Region of the Type 1 AGN NGC 4151 at a Hundred Microarcsecond Scale as Resolved by the CHARA Array Interferometer |
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| المؤلفون: | Makoto Kishimoto, Matthew Anderson, Theo ten Brummelaar, Christopher Farrington, Robert Antonucci, Sebastian Hönig, Florentin Millour, Konrad R. W. Tristram, Gerd Weigelt, Laszlo Sturmann, Judit Sturmann, Gail Schaefer, Nic Scott |
| المصدر: | The Astrophysical Journal. 940:28 |
| بيانات النشر: | American Astronomical Society, 2022. |
| سنة النشر: | 2022 |
| مصطلحات موضوعية: | Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies |
| الوصف: | The nuclear region of Type 1 AGNs has only been partially resolved so far in the near-infrared (IR) where we expect to see the dust sublimation region and the nucleus directly without obscuration. Here we present the near-IR interferometric observation of the brightest Type 1 AGN NGC4151 at long baselines of ~250 m using the CHARA Array, reaching structures at hundred micro-arcsecond scales. The squared visibilities decrease down to as low as ~0.25, definitely showing that the structure is resolved. Furthermore, combining with the previous visibility measurements at shorter baselines but at different position angles, we show that the structure is elongated *perpendicular* to the polar axis of the nucleus, as defined by optical polarization and a linear radio jet. A thin-ring fit gives a minor/major axis ratio of ~0.7 at a radius ~0.5 mas (~0.03 pc). This is consistent with the case where the sublimating dust grains are distributed preferentially in an equatorial plane in a ring-like geometry, viewed at an inclination angle of ~40 deg. Recent mid-IR interferometric finding of polar-elongated geometry at a pc scale, together with a larger-scale polar outflow as spectrally resolved by the HST, would generally suggest a dusty, conical and hollow outflow being launched presumably in the dust sublimation region. This might potentially lead to a polar-elongated morphology in the near-IR, as opposed to the results here. We discuss a possible scenario where an episodic, one-off anisotropic acceleration formed a polar-fast and equatorially-slow velocity distribution, having lead to an effectively flaring geometry as we observe. Accepted for publication in ApJ |
| تدمد: | 1538-4357 0004-637X |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7b1e37e998d56d82ed3468df20d32435 https://doi.org/10.3847/1538-4357/ac91c4 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....7b1e37e998d56d82ed3468df20d32435 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15384357 0004637X |
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