An Intermediate Mass Black Hole Hidden Behind Thick Obscuration
Fuente:
arXiv
Salvato in:
| Autori principali: | , , , , , , , , , , , , , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2024
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866912066877521920 |
|---|---|
| author | Boorman, Peter G. Stern, Daniel Assef, Roberto J. Borkar, Abhijeet Brightman, Murray Buchner, Johannes Chen, Chien-Ting Earnshaw, Hannah P. Harrison, Fiona A. Matzeu, Gabriele A. Pfeifle, Ryan W. Ricci, Claudio Svoboda, Jiří Torres-Albà, Núria Zaw, Ingyin |
| author_facet | Boorman, Peter G. Stern, Daniel Assef, Roberto J. Borkar, Abhijeet Brightman, Murray Buchner, Johannes Chen, Chien-Ting Earnshaw, Hannah P. Harrison, Fiona A. Matzeu, Gabriele A. Pfeifle, Ryan W. Ricci, Claudio Svoboda, Jiří Torres-Albà, Núria Zaw, Ingyin |
| contents | Recent models suggest approximately half of all accreting supermassive black holes (SMBHs; $M_{\rm BH}$ $\gtrsim$ 10$^{5}$ M$_{\odot}$) are expected to undergo intense growth phases behind Compton-thick ($N_{\rm H}$ $>$ 1.5 $\times$ 10$^{24}$ cm$^{-2}$) veils of obscuring gas. However, despite being a viable source for the seeding of SMBHs, there are currently no examples known of a Compton-thick accreting intermediate mass black hole (IMBH; $M_{\rm BH}$ $\sim$ 10$^{2}$ $-$ 10$^{5}$ M$_{\odot}$). We present a detailed X-ray spectral analysis of IC 750 $-$ the only AGN to-date with a precise megamaser-based intermediate mass $<$ 10$^{5}$ M$_{\odot}$. We find the equivalent width of neutral 6.4 keV Fe K$α$ to be 1.9$^{+2.2}_{-1.0}$ keV via phenomenological modelling of the co-added 177 ks Chandra spectrum. Such large equivalent widths are seldom produced by processes other than fluorescence from dense obscuration. We fit three physically-motivated X-ray spectral models to infer a range of possible intrinsic 2$-$10 keV luminosity posteriors that encompass the systematic uncertainties associated with a choice of model. Despite a wide range of predicted intrinsic 2$-$10 keV luminosities between $\sim$ 10$^{41}$ and 10$^{43}$ erg s$^{-1}$, all three models agree that IC 750 has a Compton-thick line-of-sight column density to $>$ 99\% confidence. Compton-thick obscuration is well-documented to impinge substantial bias on the pursuit of SMBH AGN. Our results thus provide the first indication that Compton-thick obscuration should also be properly considered to uncover and understand the IMBH population in an unbiased manner. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2410_07342 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | An Intermediate Mass Black Hole Hidden Behind Thick Obscuration Boorman, Peter G. Stern, Daniel Assef, Roberto J. Borkar, Abhijeet Brightman, Murray Buchner, Johannes Chen, Chien-Ting Earnshaw, Hannah P. Harrison, Fiona A. Matzeu, Gabriele A. Pfeifle, Ryan W. Ricci, Claudio Svoboda, Jiří Torres-Albà, Núria Zaw, Ingyin High Energy Astrophysical Phenomena Astrophysics of Galaxies Recent models suggest approximately half of all accreting supermassive black holes (SMBHs; $M_{\rm BH}$ $\gtrsim$ 10$^{5}$ M$_{\odot}$) are expected to undergo intense growth phases behind Compton-thick ($N_{\rm H}$ $>$ 1.5 $\times$ 10$^{24}$ cm$^{-2}$) veils of obscuring gas. However, despite being a viable source for the seeding of SMBHs, there are currently no examples known of a Compton-thick accreting intermediate mass black hole (IMBH; $M_{\rm BH}$ $\sim$ 10$^{2}$ $-$ 10$^{5}$ M$_{\odot}$). We present a detailed X-ray spectral analysis of IC 750 $-$ the only AGN to-date with a precise megamaser-based intermediate mass $<$ 10$^{5}$ M$_{\odot}$. We find the equivalent width of neutral 6.4 keV Fe K$α$ to be 1.9$^{+2.2}_{-1.0}$ keV via phenomenological modelling of the co-added 177 ks Chandra spectrum. Such large equivalent widths are seldom produced by processes other than fluorescence from dense obscuration. We fit three physically-motivated X-ray spectral models to infer a range of possible intrinsic 2$-$10 keV luminosity posteriors that encompass the systematic uncertainties associated with a choice of model. Despite a wide range of predicted intrinsic 2$-$10 keV luminosities between $\sim$ 10$^{41}$ and 10$^{43}$ erg s$^{-1}$, all three models agree that IC 750 has a Compton-thick line-of-sight column density to $>$ 99\% confidence. Compton-thick obscuration is well-documented to impinge substantial bias on the pursuit of SMBH AGN. Our results thus provide the first indication that Compton-thick obscuration should also be properly considered to uncover and understand the IMBH population in an unbiased manner. |
| title | An Intermediate Mass Black Hole Hidden Behind Thick Obscuration |
| topic | High Energy Astrophysical Phenomena Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2410.07342 |