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Broad absorption line quasars in the Dark Energy Spectroscopic Instrument Early Data Release (2024)
Journal Article
Filbert, S., Martini, P., Seebaluck, K., Ennesser, L., Alexander, D. M., Bault, A., Brodzeller, A., Herrera-Alcantar, H. K., Montero-Camacho, P., Pérez-Ràfols, I., Ramírez-Pérez, C., Ravoux, C., Tan, T., Aguilar, J., Ahlen, S., Bailey, S., Brooks, D., Claybaugh, T., Dawson, K., de la Macorra, A., …Zhou, Z. (2024). Broad absorption line quasars in the Dark Energy Spectroscopic Instrument Early Data Release. Monthly Notices of the Royal Astronomical Society, 532(4), 3669-3681. https://doi.org/10.1093/mnras/stae1610

Accretion properties of X-ray AGN: evidence for radiation-regulated obscuration with redshift-dependent host galaxy contribution (2024)
Journal Article
Laloux, B., Georgakakis, A., Alexander, D. M., Buchner, J., Andonie, C., Acharya, N., Aird, J., Alonso-Tetilla, A. V., Bongiorno, A., Hickox, R. C., Lapi, A., Musiimenta, B., Almeida, C. R., Villforth, C., & Shankar, F. (2024). Accretion properties of X-ray AGN: evidence for radiation-regulated obscuration with redshift-dependent host galaxy contribution. Monthly Notices of the Royal Astronomical Society, 532(3), 3459-3479. https://doi.org/10.1093/mnras/stae1649

Ionised AGN outflows in the Goldfish galaxy: The illuminating and interacting red quasar eFEDSJ091157.4+014327 at z ∼ 0.6 (2024)
Journal Article
Musiimenta, B., Speranza, G., Urrutia, T., Brusa, M., Ramos Almeida, C., Perna, M., López, I. E., Alexander, D., Laloux, B., Shankar, F., Lapi, A., Salvato, M., Toba, Y., Andonie, C., & Rodríguez, I. M. (2024). Ionised AGN outflows in the Goldfish galaxy: The illuminating and interacting red quasar eFEDSJ091157.4+014327 at z ∼ 0.6. Astronomy & Astrophysics, 687, Article A111. https://doi.org/10.1051/0004-6361/202449283

Context. Evolutionary models suggest that the initial growth phases of active galactic nuclei (AGN) and their central supermassive black holes (SMBHs) are dust-enshrouded and characterised by jet or wind outflows that should gradually clear the inter... Read More about Ionised AGN outflows in the Goldfish galaxy: The illuminating and interacting red quasar eFEDSJ091157.4+014327 at z ∼ 0.6.

The High-Energy X-ray Probe (HEX-P): the circum-nuclear environment of growing supermassive black holes (2024)
Journal Article
Boorman, P. G., Torres-Albà, N., Annuar, A., Marchesi, S., Pfeifle, R. W., Stern, D., …The HEX-P Collaboration. (2024). The High-Energy X-ray Probe (HEX-P): the circum-nuclear environment of growing supermassive black holes. Frontiers in Astronomy and Space Sciences, 11, Article 1335459. https://doi.org/10.3389/fspas.2024.1335459

Ever since the discovery of the first active galactic nuclei (AGN), substantial observational and theoretical effort has been invested into understanding how massive black holes have evolved across cosmic time. Circum-nuclear obscuration is now estab... Read More about The High-Energy X-ray Probe (HEX-P): the circum-nuclear environment of growing supermassive black holes.

Cosmic evolution of radio-excess active galactic nuclei in quiescent and star-forming galaxies across 0 < z < 4 (2024)
Journal Article
Wang, Y., Wang, T., Liu, D., Sargent, M. T., Gao, F., Alexander, D. M., …Jin, S. (2024). Cosmic evolution of radio-excess active galactic nuclei in quiescent and star-forming galaxies across 0 < z < 4. Astronomy & Astrophysics, 685, Article A79. https://doi.org/10.1051/0004-6361/202347787

Context. Radio-excess active galactic nuclei (radio-AGNs) are essential to our understanding of both the physics of black hole (BH) accretion and the interaction between BHs and host galaxies. Recent deep and wide radio continuum surveys have made it... Read More about Cosmic evolution of radio-excess active galactic nuclei in quiescent and star-forming galaxies across 0 < z < 4.

The high energy X-ray probe (HEX-P): bringing the cosmic X-ray background into focus (2024)
Journal Article
Civano, F., Zhao, X., Boorman, P. G., Marchesi, S., Ananna, T., Creech, S., …Torres-Albà, N. (2024). The high energy X-ray probe (HEX-P): bringing the cosmic X-ray background into focus. Frontiers in Astronomy and Space Sciences, 11, Article 1340719. https://doi.org/10.3389/fspas.2024.1340719

Since the discovery of the cosmic X-ray background (CXB), astronomers have strived to understand the accreting supermassive black holes (SMBHs) contributing to its peak in the 10–40 keV band. Existing soft X-ray telescopes could study this population... Read More about The high energy X-ray probe (HEX-P): bringing the cosmic X-ray background into focus.

How does the radio enhancement of broad absorption line quasars relate to colour and accretion rate? (2024)
Journal Article
Petley, J. W., Morabito, L. K., Rankine, A. L., Richards, G. T., Thomas, N. L., Alexander, D. M., …Kolwa, S. (2024). How does the radio enhancement of broad absorption line quasars relate to colour and accretion rate?. Monthly Notices of the Royal Astronomical Society, 529(3), 1995-2007. https://doi.org/10.1093/mnras/stae626

The origin of radio emission in different populations of radio-quiet quasars is relatively unknown, but recent work has uncovered various drivers of increased radio-detection fraction. In this work, we pull together three known factors: optical colou... Read More about How does the radio enhancement of broad absorption line quasars relate to colour and accretion rate?.

A post-merger enhancement only in star-forming Type 2 Seyfert galaxies: the deep learning view (2024)
Journal Article
Avirett-Mackenzie, M. S., Villforth, C., Huertas-Company, M., Wuyts, S., Alexander, D. M., Bonoli, S., …Shankar, F. (2024). A post-merger enhancement only in star-forming Type 2 Seyfert galaxies: the deep learning view. Monthly Notices of the Royal Astronomical Society, 528(4), 6915-6933. https://doi.org/10.1093/mnras/stae183

Supermassive black holes require a reservoir of cold gas at the centre of their host galaxy in order to accrete and shine as active galactic nuclei (AGN). Major mergers have the ability to drive gas rapidly inwards, but observations trying to link me... Read More about A post-merger enhancement only in star-forming Type 2 Seyfert galaxies: the deep learning view.

Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. I. Sample from the Early Data (2024)
Journal Article
Guo, W.-J., Zou, H., Fawcett, V. A., Canning, R., Juneau, S., Davis, T. M., Alexander, D. M., Jiang, L., Aguilar, J. N., Ahlen, S., Brooks, D., Claybaugh, T., de la Macorra, A., Doel, P., Fanning, K., Forero-Romero, J. E., Gontcho A Gontcho, S., Honscheid, K., Kisner, T., Kremin, A., …Zhou, Z. (2024). Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. I. Sample from the Early Data. Astrophysical Journal Supplement, 270(2), Article 26. https://doi.org/10.3847/1538-4365/ad118a

Changing-look active galactic nuclei (CL AGNs) can be generally confirmed by the emergence (turn-on) or disappearance (turn-off) of broad emission lines (BELs), associated with a transient timescale (about 100 ∼ 5000 days) that is much shorter than p... Read More about Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. I. Sample from the Early Data.

DESI Survey Validation Data in the COSMOS/Hyper Suprime-Cam Field: Cool Gas Trace Main-sequence Star-forming Galaxies at the Cosmic Noon (2023)
Journal Article
Zou, S., Jiang, L., Cai, Z., Moustakas, J., Sun, Z., Pan, Z., …Zhou, Z. (2024). DESI Survey Validation Data in the COSMOS/Hyper Suprime-Cam Field: Cool Gas Trace Main-sequence Star-forming Galaxies at the Cosmic Noon. Astrophysical Journal, 960(1), Article 34. https://doi.org/10.3847/1538-4357/ad09b2

We present the first result in exploring the gaseous halo and galaxy correlation using the Dark Energy Spectroscopic Instrument survey validation data in the Cosmic Evolution Survey (COSMOS) and Hyper Suprime-Cam field. We obtain multiphase gaseous h... Read More about DESI Survey Validation Data in the COSMOS/Hyper Suprime-Cam Field: Cool Gas Trace Main-sequence Star-forming Galaxies at the Cosmic Noon.

A new discovery space opened by eROSITA: Ionised AGN outflows from X-ray selected samples (2023)
Journal Article
Musiimenta, B., Brusa, M., Liu, T., Salvato, M., Buchner, J., Igo, Z., …Wolf, J. (2023). A new discovery space opened by eROSITA: Ionised AGN outflows from X-ray selected samples. Astronomy & Astrophysics, 679, Article A84. https://doi.org/10.1051/0004-6361/202245555

Context. In the context of an evolutionary model, the outflow phase of an active galactic nucleus (AGN) occurs at the peak of its activity, once the central supermassive black hole (SMBH) is massive enough to generate sufficient power to counterbalan... Read More about A new discovery space opened by eROSITA: Ionised AGN outflows from X-ray selected samples.

Quasar feedback survey: molecular gas affected by central outflows and by ∼10-kpc radio lobes reveal dual feedback effects in ‘radio quiet’ quasars (2023)
Journal Article
Girdhar, A., Harrison, C. M., Mainieri, V., Fernández Aranda, R., Arrigoni Battaia, F., Bianchin, M., …Ward, S. R. (2024). Quasar feedback survey: molecular gas affected by central outflows and by ∼10-kpc radio lobes reveal dual feedback effects in ‘radio quiet’ quasars. Monthly Notices of the Royal Astronomical Society, 527(3), 9322-9342. https://doi.org/10.1093/mnras/stad3453

DESI z ≳ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ∼ 4.7–6.6 (2023)
Journal Article
Yang, J., Fan, X., Gupta, A., Myers, A. D., Palanque-Delabrouille, N., Wang, F., …Zou, H. (2023). DESI z ≳ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ∼ 4.7–6.6. Astrophysical Journal Supplement, 269(1), Article 27. https://doi.org/10.3847/1538-4365/acf99b

We report the first results of a high-redshift (z ≳ 5) quasar survey using the Dark Energy Spectroscopic Instrument (DESI). As a DESI secondary target program, this survey is designed to carry out a systematic search and investigation of quasars at 4... Read More about DESI z ≳ 5 Quasar Survey. I. A First Sample of 400 New Quasars at z ∼ 4.7–6.6.

Probing the roles of orientation and multiscale gas distributions in shaping the obscuration of active galactic nuclei through cosmic time (2023)
Journal Article
Alonso-Tetilla, A. V., Shankar, F., Fontanot, F., Menci, N., Valentini, M., Buchner, J., …Ramos Almeida, C. (2024). Probing the roles of orientation and multiscale gas distributions in shaping the obscuration of active galactic nuclei through cosmic time. Monthly Notices of the Royal Astronomical Society, 527(4), 10878-10896. https://doi.org/10.1093/mnras/stad3265

The origin of obscuration in active galactic nuclei (AGNs) is still an open debate. In particular, it is unclear what drives the relative contributions to the line-of-sight column densities from galaxy-scale and torus-linked obscuration. The latter s... Read More about Probing the roles of orientation and multiscale gas distributions in shaping the obscuration of active galactic nuclei through cosmic time.

The Quasar Feedback Survey: characterizing CO excitation in quasar host galaxies (2023)
Journal Article
Alexander, D., Calistro Rivera, G., De Breuck, C., Harrison, C. M., Mainieri, V., Lundgren, A., …Smit, R. (2024). The Quasar Feedback Survey: characterizing CO excitation in quasar host galaxies. Monthly Notices of the Royal Astronomical Society, 527(3), 4420–4439. https://doi.org/10.1093/mnras/stad3133

We present a comprehensive study of the molecular gas properties of 17Type 2 quasars at z <0.2 from the Quasar Feedback Survey
(L[O III] > 1042.1 ergs−1), selected by their high [O III] luminosities and displaying a large diversity of radio jet prop... Read More about The Quasar Feedback Survey: characterizing CO excitation in quasar host galaxies.

Detecting and Characterizing Mg ii Absorption in DESI Survey Validation Quasar Spectra (2023)
Journal Article
Napolitano, L., Pandey, A., Myers, A. D., Lan, T., Anand, A., Aguilar, J., …Zou, S. (2023). Detecting and Characterizing Mg ii Absorption in DESI Survey Validation Quasar Spectra. Astronomical Journal, 166(3), Article 99. https://doi.org/10.3847/1538-3881/ace62c

We present findings of the detection of Magnesium II (Mg ii, λ = 2796, 2803 Å) absorbers from the early data release of the Dark Energy Spectroscopic Instrument (DESI). DESI is projected to obtain spectroscopy of approximately 3 million quasars (QSOs... Read More about Detecting and Characterizing Mg ii Absorption in DESI Survey Validation Quasar Spectra.

Performance of the Quasar Spectral Templates for the Dark Energy Spectroscopic Instrument (2023)
Journal Article
Brodzeller, A., Dawson, K., Bailey, S., Yu, J., Ross, A. J., Bault, A., …Zhou, Z. (2023). Performance of the Quasar Spectral Templates for the Dark Energy Spectroscopic Instrument. Astronomical Journal, 166(2), Article 66. https://doi.org/10.3847/1538-3881/ace35d

Millions of quasar spectra will be collected by the Dark Energy Spectroscopic Instrument (DESI), leading to a fourfold increase in the number of known quasars. High-accuracy quasar classification is essential to tighten constraints on cosmological pa... Read More about Performance of the Quasar Spectral Templates for the Dark Energy Spectroscopic Instrument.

Revisiting the Properties of X-Ray Active Galactic Nuclei in the SSA22 Protocluster: Normal Supermassive Black Hole and Host-galaxy Growth for AGNs in a z = 3.09 Overdensity (2023)
Journal Article
Monson, E. B., Doore, K., Eufrasio, R. T., Lehmer, B. D., Alexander, D. M., Harrison, C. M., …Umehata, H. (2023). Revisiting the Properties of X-Ray Active Galactic Nuclei in the SSA22 Protocluster: Normal Supermassive Black Hole and Host-galaxy Growth for AGNs in a z = 3.09 Overdensity. Astrophysical Journal, 951(1), Article 15. https://doi.org/10.3847/1538-4357/acd449

We analyze the physical properties of eight X-ray-selected active galactic nuclei (AGNs) and one candidate protoquasar system (ADF22A1) in the z = 3.09 SSA22 protocluster by fitting their X-ray-to-IR spectral energy distributions (SEDs) using our SED... Read More about Revisiting the Properties of X-Ray Active Galactic Nuclei in the SSA22 Protocluster: Normal Supermassive Black Hole and Host-galaxy Growth for AGNs in a z = 3.09 Overdensity.

The Most Obscured AGNs in the XMM-SERVS Fields (2023)
Journal Article
Yan, W., Brandt, W. N., Zou, F., Zhu, S., Chen, C. J., Hickox, R. C., …Vito, F. (2023). The Most Obscured AGNs in the XMM-SERVS Fields. Astrophysical Journal, 951(1), Article 27. https://doi.org/10.3847/1538-4357/accea6

We perform X-ray spectral analyses to derive the characteristics (e.g., column density, X-ray luminosity) of ≈10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey, which was designed to investigate the gr... Read More about The Most Obscured AGNs in the XMM-SERVS Fields.