NuSTAR UNVEILS A HEAVILY OBSCURED LOW-LUMINOSITY ACTIVE GALACTIC NUCLEUS IN THE LUMINOUS INFRARED GALAXY NGC 6286

Ricci, Cláudio; Bauer, F. E.; Treister, Ezequiel; Romero-Cañizales, C.; Arévalo, P.; Iwasawa, K.; Privon, George C.; Sanders, D. B.; Schawinski, Kevin; Stern, Daniel; Imanishi, Masatoshi

doi:10.3847/0004-637x/819/1/4

Cited by 37 publications

(35 citation statements)

References 144 publications

(202 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 11. The hard X-ray luminosity versus the mid-infrared luminosity for the sample of hard-X-ray-selected AGNs from the 70 month Swift/BAT survey for which a detailed broadband spectral analysis enables a direct determination of the intrinsic absorption (Ricci et al 2015(Ricci et al , 2016, showing unabsorbed ( < N 10 ) AGNs. We also plot the advanced mergers from this work, and the confirmed duals listed in Table 8 for which X-ray and mid-infrared fluxes are available.…”

Section: Discussionmentioning

confidence: 99%

Buried AGNs in Advanced Mergers: Mid-infrared Color Selection as a Dual AGN Candidate Finder

Satyapal

Secrest

Ricci

et al. 2017

ApJ

131

View full text Add to dashboard Cite

A direct consequence of hierarchical galaxy formation is the existence of dual supermassive black holes, which may be preferentially triggered as active galactic nuclei (AGNs) during galaxy mergers. Despite decades of searching, however, dual AGNs are extremely rare, and most have been discovered serendipitously. Using the all-sky WISE survey, we identified a population of over 100 morphologically identified interacting galaxies or mergers that display red mid-infrared colors often associated in extragalactic sources with powerful AGNs. The vast majority of these advanced mergers are optically classified as star-forming galaxies, which suggests that they may represent an obscured population of AGNs that cannot be found through optical studies. In this work, we present Chandra/ACIS observations and near-infrared spectra with the Large Binocular Telescope of six advanced mergers with projected pair separations less than ∼10 kpc. The combined X-ray, near-infrared, and mid-infrared properties of these mergers provide confirmation that four out of the six mergers host at least one AGN, with four of the mergers possibly hosting dual AGNs with projected separations less than ∼10 kpc, despite showing no firm evidence for AGNs based on optical spectroscopic studies. Our results demonstrate that (1) optical studies miss a significant fraction of single and dual AGNs in advanced mergers, and (2) mid-infrared pre-selection is extremely effective in identifying dual AGN candidates in late-stage mergers. Our multi-wavelength observations suggest that the buried AGNs in these mergers are highly absorbed, with intrinsic column densities in excess of~> N 10 H 24 cm −2, consistent with hydrodynamic simulations.

show abstract

Section: Discussionmentioning

confidence: 99%

Buried AGNs in Advanced Mergers: Mid-infrared Color Selection as a Dual AGN Candidate Finder

Satyapal

Secrest

Ricci

et al. 2017

ApJ

131

View full text Add to dashboard Cite

show abstract

“…This AGN, however, has a low intrinsic luminosity, and contributes less than 1% of the bolometric luminosity of the system (Ricci et al 2016). The companion nucleus NGC 6285 was undetected by NuSTAR (Ricci et al 2016). In Figure 21, we display the diffuse X-ray spectrum for Arp 293, along with the best-fit model.…”

Section: 78±mentioning

confidence: 99%

“…Based on infrared spectra, Dixon & Joseph (2011) conclude that less than half of the infrared luminosity of NGC 6286 is powered by an AGN. Ricci et al (2016) analyzed the archival Chandra data for Arp 293 jointly with XMM-Newton and NuSTAR data, and concluded that NGC 6286 contains a buried AGN. This AGN, however, has a low intrinsic luminosity, and contributes less than 1% of the bolometric luminosity of the system (Ricci et al 2016).…”

Section: 78±mentioning

confidence: 99%

“…Ricci et al (2016) analyzed the archival Chandra data for Arp 293 jointly with XMM-Newton and NuSTAR data, and concluded that NGC 6286 contains a buried AGN. This AGN, however, has a low intrinsic luminosity, and contributes less than 1% of the bolometric luminosity of the system (Ricci et al 2016). The companion nucleus NGC 6285 was undetected by NuSTAR (Ricci et al 2016).…”

Section: 78±mentioning

confidence: 99%

See 1 more Smart Citation

Diffuse X-Ray-emitting Gas in Major Mergers

Smith

Campbell

Struck

et al. 2018

View full text Add to dashboard Cite

Using archived data from the Chandra X-ray telescope, we have extracted the diffuse Xray emission from 49 equal-mass interacting/merging galaxy pairs in a merger sequence, from widely separated pairs to merger remnants. After removal of contributions from unresolved point sources, we compared the diffuse thermal X-ray luminosity from hot gas (L X (gas)) with the global star formation rate (SFR). After correction for absorption within the target galaxy, we do not see strong trend of L X (gas)/SFR with SFR or merger stage for galaxies with SFR > 1 M ⊙ yr −1 . For these galaxies, the median L X (gas)/SFR is 5.5 × 10 39 ((erg s −1 )/M ⊙ yr −1 )), similar to that of normal spiral galaxies. These results suggest that stellar feedback in star forming galaxies reaches an approximately steady state condition, in which a relatively constant fraction of about 2% of the total energy output from supernovae and stellar winds is converted into X-ray flux. Three late-stage merger remnants with low SFRs and high K band luminosities (L K ) have enhanced L X (gas)/SFR; their UV/IR/optical colors suggest that they are post-starburst galaxies, perhaps in the process of becoming ellipticals. Systems with L K < 10 10 L ⊙ have lower L X (gas)/SFR ratios than the other galaxies in our sample, perhaps due to lower gravitational fields or lower metallicities. We see no relation between L X (gas)/SFR and Seyfert activity in this sample, suggesting that feedback from active galactic nuclei is not a major contributor to the hot gas in our sample galaxies.

show abstract

“…To better constrain the X-ray absorption of hot DOGs and hence their intrinsic X-ray luminosities, it is necessary to obtain reliable detections at  E 10 keV, where their emission is less affected by neutral gas absorption (e.g., Annuar et al 2015;Lansbury et al 2015;Puccetti et al 2016;Ricci et al 2016aRicci et al , 2016bTanimoto et al 2016). The simplest way to do this is to observe brighter, lower-redshift sources.…”

Section: Introductionmentioning

confidence: 99%

NuSTAR OBSERVATIONS OF WISE J1036+0449, A GALAXY AT z ∼ 1 OBSCURED BY HOT DUST

Ricci

Assef

Stern

et al. 2017

ApJ

Self Cite

View full text Add to dashboard Cite

Hot, Dust-Obscured Galaxies (Hot DOGs), selected from the WISE all sky infrared survey, host some of the most powerful Active Galactic Nuclei (AGN) known, and might represent an important stage in the evolution of galaxies. Most known Hot DOGs are at z > 1.5, due in part to a strong bias against identifying them at lower redshift related to the selection criteria. We present a new selection method that identifies 153 Hot DOG candidates at z ∼ 1, where they are significantly brighter and easier to study. We validate this approach by measuring a redshift z = 1.009, and an SED similar to higher redshift Hot DOGs for one of these objects, WISE J1036+0449 (L Bol ≃ 8 × 10 46 erg s −1 ), using data from Keck/LRIS and NIRSPEC, SDSS, and CSO. We find evidence of a broadened component in Mg ii, which, if due to the gravitational potential of the supermassive black hole, would imply a black hole mass of M BH ≃ 2 × 10 8 M ⊙ , and an Eddington ratio of λ Edd ≃ 2.7. WISE J1036+0449 is the first Hot DOG detected by NuSTAR, and the observations show that the source is heavily obscured, with a column density of N H ≃ (2 − 15) × 10 23 cm −2 . The source has an intrinsic 2-10 keV luminosity of ∼ 6×10 44 erg s −1 , a value significantly lower than that expected from the mid-infrared/Xray correlation. We also find that the other Hot DOGs observed by X-ray facilities show a similar deficiency of X-ray flux. We discuss the origin of the X-ray weakness and the absorption properties of Hot DOGs. Hot DOGs at z 1 could be excellent laboratories to probe the characteristics of the accretion flow and of the X-ray emitting plasma at extreme values of the Eddington ratio.

show abstract

NuSTAR UNVEILS A HEAVILY OBSCURED LOW-LUMINOSITY ACTIVE GALACTIC NUCLEUS IN THE LUMINOUS INFRARED GALAXY NGC 6286

Cited by 37 publications

References 144 publications

Buried AGNs in Advanced Mergers: Mid-infrared Color Selection as a Dual AGN Candidate Finder

Buried AGNs in Advanced Mergers: Mid-infrared Color Selection as a Dual AGN Candidate Finder

Diffuse X-Ray-emitting Gas in Major Mergers

NuSTAR OBSERVATIONS OF WISE J1036+0449, A GALAXY AT z ∼ 1 OBSCURED BY HOT DUST

Contact Info

Product

Resources

About