text: 159,31,1196712613339639808,409901833,Peter Boorman,"🚨 New @NASANuSTAR paper time! Work led by Steph LaMassa with new NuSTAR and archival @chandraxray data of the spiral galaxy NGC 4968 revealed the accreting supermassive black hole at its center to be obscured by very thick thunderclouds of gas ⛈ <LINK> Pivotal to this work was the high-energy data from @NASANuSTAR which gave us powerful ""X-ray vision"" to separately study the material that reflects stray X-rays towards us from the material absorbing X-rays travelling along our line of sight. This tells us not only how obscured the black hole is along our line of sight, but also how much material surrounds the black hole on average. One would expect these amounts to be different for a clumpy configuration, for instance. But why should you care? Well... NGC 4968 is very close to us (just 7x as far as the Whirlpool), yet the supermassive black hole would have gone unnoticed in high-energy X-rays due to that pesky obscuration if it weren't for the sensitivity of @NASANuSTAR. This is known to be a big problem for detecting heavily obscured black holes with X-ray vision, since large amounts of material can severley hinder our chances of even the highest energy X-rays from reaching our telescopes. But finding them is very important. Evidence suggests that supermassive black holes grow most rapidly during heavily obscured phases, so studying them could be the key to understanding how these monsters have grown so huge since their birth near the beginning of the Universe!",https://arxiv.org/abs/1911.05813,"We present the analysis of Chandra and NuSTAR spectra of NGC 4968, a local (D$\sim$44 Mpc) 12$\mu$m-selected Seyfert 2 galaxy, enshrouded within Compton-thick layers of obscuring gas. We find no evidence of variability between the Chandra and NuSTAR observations (separated by 2 years), and between the two NuSTAR observations (separated by 10 months). Using self-consistent X-ray models, we rule out the scenario where the obscuring medium is nearly spherical and uniform, contradicting the results implied by the $<$10 keV Chandra spectrum. The line-of-sight column density, from intervening matter between the source and observer that intercepts the intrinsic AGN X-ray emission, is well within the Compton-thick regime, with a minimum column density of $2\times10^{24}$ cm$^{-2}$. The average global column density is high ($> 3\times10^{23}$ cm$^{-2}$), with both Compton-thick and Compton-thin solutions permitted depending on the X-ray spectral model. The spectral models provide a range of intrinsic AGN continuum parameters and implied 2-10 keV luminosities ($L_{\rm 2-10keV,intrinsic}$), where the higher end of $L_{\rm 2-10keV,intrinsic}$ is consistent with expectations from the 12$\mu$m luminosity ($L_{\rm 2-10keV,intrinisc} \sim 7\times10^{42}$ erg s$^{-1}$). Compared with Compton-thick AGN previously observed by {\it NuSTAR}, NGC 4968 is among the most intrinsically X-ray luminous. However, despite its close proximity and relatively high intrinsic X-ray luminosity, it is undetected by the 105 month Swift-BAT survey, underscoring the importance of multi-wavelength selection for obtaining the most complete census of the most hidden black holes. ",NuSTAR Uncovers an Extremely Local Compton-thick AGN in NGC 4968,6,"['🚨 New @NASANuSTAR paper time! Work led by Steph LaMassa with new NuSTAR and archival @chandraxray  data of the spiral galaxy NGC 4968 revealed the accreting supermassive black hole at its center to be obscured by very thick thunderclouds of gas ⛈ <LINK>', 'Pivotal to this work was the high-energy data from @NASANuSTAR which gave us powerful ""X-ray vision"" to separately study the material that reflects stray X-rays towards us from the material absorbing X-rays travelling along our line of sight.', 'This tells us not only how obscured the black hole is along our line of sight, but also how much material surrounds the black hole on average. One would expect these amounts to be different for a clumpy configuration, for instance.', ""But why should you care? Well... NGC 4968 is very close to us (just 7x as far as the Whirlpool), yet the supermassive black hole would have gone unnoticed in high-energy X-rays due to that pesky obscuration if it weren't for the sensitivity of @NASANuSTAR."", 'This is known to be a big problem for detecting heavily obscured black holes with X-ray vision, since large amounts of material can severley hinder our chances of even the highest energy X-rays from reaching our telescopes.', 'But finding them is very important. Evidence suggests that supermassive black holes grow most rapidly during heavily obscured phases, so studying them could be the key to understanding how these monsters have grown so huge since their birth near the beginning of the Universe!']",19,11,1485