Outputs (14)

The demographics of obscured AGN from X-ray spectroscopy guided by multiwavelength information (2022)
Journal Article
Laloux, B., Georgakakis, A., Andonie, C., Alexander, D. M., Ruiz, A., Rosario, D. J., Aird, J., Buchner, J., Carrera, F. J., Lapi, A., Ramos Almeida, C., Salvato, M., & Shankar, F. (2023). The demographics of obscured AGN from X-ray spectroscopy guided by multiwavelength information. Monthly Notices of the Royal Astronomical Society, 518(2), 2546-2566. https://doi.org/10.1093/mnras/stac3255

A complete census of active galactic nuclei (AGNs) is a prerequisite for understanding the growth of supermassive black holes across cosmic time. A significant challenge towards this goal is the whereabouts of heavily obscured AGN that remain uncerta... Read More about The demographics of obscured AGN from X-ray spectroscopy guided by multiwavelength information.

A panchromatic view of infrared quasars: excess star formation and radio emission in the most heavily obscured systems (2022)
Journal Article
Andonie, C., Alexander, D. M., Rosario, D., Laloux, B., Georgakakis, A., Morabito, L. K., Villforth, C., Avirett-Mackenzie, M., Rivera, G. C., Del Moro, A., Fotopoulou, S., Harrison, C., Lapi, A., Petley, J., Petter, G., & Shankar, F. (2022). A panchromatic view of infrared quasars: excess star formation and radio emission in the most heavily obscured systems. Monthly Notices of the Royal Astronomical Society, 517(2), 2577-2598. https://doi.org/10.1093/mnras/stac2800

To understand the active galactic nuclei (AGNs) phenomenon and their impact on the evolution of galaxies, a complete AGN census is required; however, finding heavily obscured AGNs is observationally challenging. Here we use the deep and extensive mul... Read More about A panchromatic view of infrared quasars: excess star formation and radio emission in the most heavily obscured systems.

Warm molecular and ionized gas kinematics in the type-2 quasar J0945+1737 (2022)
Journal Article
Speranza, G., Ramos Almeida, C., Acosta-Pulido, J., Riffel, R., Tadhunter, C., Pierce, J., Rodríguez-Ardila, A., Coloma Puga, M., Brusa, M., Musiimenta, B., Alexander, D., Lapi, A., Shankar, F., & Villforth, C. (2022). Warm molecular and ionized gas kinematics in the type-2 quasar J0945+1737. Astronomy & Astrophysics, 665, Article A55. https://doi.org/10.1051/0004-6361/202243585

We analyse Near-Infrared Integral Field Spectrograph (NIFS) observations of the type-2 quasar (QSO2) SDSS J094521.33+173753.2 to investigate its warm molecular and ionized gas kinematics. This QSO2 has a bolometric luminosity of 1045.7 erg s−1 and a... Read More about Warm molecular and ionized gas kinematics in the type-2 quasar J0945+1737.

NuSTAR Observations of Intrinsically X-Ray Weak Quasar Candidates: An Obscuration-only Scenario (2022)
Journal Article
Wang, C., Luo, B., Brandt, W., Alexander, D., Bauer, F., Gallagher, S., Huang, J., Liu, H., & Stern, D. (2022). NuSTAR Observations of Intrinsically X-Ray Weak Quasar Candidates: An Obscuration-only Scenario. Astrophysical Journal, 936(2), Article 95. https://doi.org/10.3847/1538-4357/ac886e

We utilize recent NuSTAR observations (co-added depth ≈55–120 ks) of PG 1001+054, PG 1254+047, and PHL 1811 to constrain their hard X-ray (≳5 keV) weakness and spectral shapes and thus to investigate the nature of their extreme X-ray weakness. These... Read More about NuSTAR Observations of Intrinsically X-Ray Weak Quasar Candidates: An Obscuration-only Scenario.

Localizing narrow Fe Kα emission within bright AGN (2022)
Journal Article
Andonie, C., Bauer, F. E., Carraro, R., Arévalo, P., Alexander, D. M., Brandt, W. N., Buchner, J., He, A., Koss, M. J., Ricci, C., Salinas, V., Solimano, M., Tortosa, A., & Treister, E. (2022). Localizing narrow Fe Kα emission within bright AGN. Astronomy & Astrophysics, 664, https://doi.org/10.1051/0004-6361/202142473

Context. The 6.4 keV Fe Kα emission line is a ubiquitous feature in X-ray spectra of active galactic nuclei (AGN), and its properties track the interaction between the variable primary X-ray continuum and the surrounding structure from which it arise... Read More about Localizing narrow Fe Kα emission within bright AGN.

The Black Hole Mass Function across Cosmic Time. II. Heavy Seeds and (Super)Massive Black Holes (2022)
Journal Article
Sicilia, A., Lapi, A., Boco, L., Shankar, F., Alexander, D. M., Allevato, V., Villforth, C., Massardi, M., Spera, M., Bressan, A., & Danese, L. (2022). The Black Hole Mass Function across Cosmic Time. II. Heavy Seeds and (Super)Massive Black Holes. Astrophysical Journal, 934(1), https://doi.org/10.3847/1538-4357/ac7873

This is the second paper in a series aimed at modeling the black hole (BH) mass function from the stellar to the (super)massive regime. In the present work, we focus on (super)massive BHs and provide an ab initio computation of their mass function ac... Read More about The Black Hole Mass Function across Cosmic Time. II. Heavy Seeds and (Super)Massive Black Holes.

Connecting radio emission to AGN wind properties with Broad Absorption Line Quasars (2022)
Journal Article
Petley, J., Morabito, L., Alexander, D., Rankine, A., Fawcett, V., Rosario, D., Matthews, J., Shimwell, T., & Drabent, A. (2022). Connecting radio emission to AGN wind properties with Broad Absorption Line Quasars. Monthly Notices of the Royal Astronomical Society, 515(4), 5159-5174. https://doi.org/10.1093/mnras/stac2067

Broad Absorption Line Quasars (BALQSOs) show strong signatures of powerful outflows, with the potential to alter the cosmic history of their host galaxies. These signatures are only seen in ∼10% of optically selected quasars, although the fraction si... Read More about Connecting radio emission to AGN wind properties with Broad Absorption Line Quasars.

Fundamental differences in the properties of red and blue quasars: measuring the reddening and accretion properties with X-shooter (2022)
Journal Article
Fawcett, V., Alexander, D., Rosario, D., Klindt, L., Lusso, E., Morabito, L., & Calistro Rivera, G. (2022). Fundamental differences in the properties of red and blue quasars: measuring the reddening and accretion properties with X-shooter. Monthly Notices of the Royal Astronomical Society, 513(1), 1254-1274. https://doi.org/10.1093/mnras/stac945

We have recently found fundamental differences in the radio properties of red quasars when compared to typical blue quasars. In this paper, we use data from the X-shooter spectrograph on the Very Large Telescope, providing spectral coverage from ∼300... Read More about Fundamental differences in the properties of red and blue quasars: measuring the reddening and accretion properties with X-shooter.

GOODS-ALMA 2.0: Starbursts in the main sequence reveal compact star formation regulating galaxy evolution prequenching (2022)
Journal Article
Gómez-Guijarro, C., Elbaz, D., Xiao, M., Kokorev, V., Magdis, G., Magnelli, B., Daddi, E., Valentino, F., Sargent, M., Dickinson, M., Béthermin, M., Franco, M., Pope, A., Kalita, B., Ciesla, L., Demarco, R., Inami, H., Rujopakarn, W., Shu, X., Wang, T., …Treister, E. (2022). GOODS-ALMA 2.0: Starbursts in the main sequence reveal compact star formation regulating galaxy evolution prequenching. Astronomy & Astrophysics, 659, Article A196. https://doi.org/10.1051/0004-6361/202142352

Compact star formation appears to be generally common in dusty star-forming galaxies (SFGs). However, its role in the framework set by the scaling relations in galaxy evolution remains to be understood. In this work we follow up on the galaxy sample... Read More about GOODS-ALMA 2.0: Starbursts in the main sequence reveal compact star formation regulating galaxy evolution prequenching.

Host Dark Matter Halos of SDSS Red and Blue Quasars: No Significant Difference in Large-scale Environment (2022)
Journal Article
Petter, G. C., Hickox, R. C., Alexander, D. M., Geach, J. E., Myers, A. D., Rosario, D. J., Fawcett, V. A., Klindt, L., & Whalen, K. E. (2022). Host Dark Matter Halos of SDSS Red and Blue Quasars: No Significant Difference in Large-scale Environment. Astrophysical Journal, 927(1), Article 16. https://doi.org/10.3847/1538-4357/ac4d31

The observed optical colors of quasars are generally interpreted in one of two frameworks: unified models that attribute the color to the random orientation of the accretion disk along the line of sight, and evolutionary models that invoke connection... Read More about Host Dark Matter Halos of SDSS Red and Blue Quasars: No Significant Difference in Large-scale Environment.

The Black Hole–Galaxy Connection: Interplay between Feedback, Obscuration, and Host Galaxy Substructure (2022)
Journal Article
Juneau, S., Goulding, A. D., Banfield, J., Bianchi, S., Duc, P.-A., Ho, I.-T., Dopita, M. A., Scharwächter, J., Bauer, F. E., Groves, B., Alexander, D. M., Davies, R. L., Elbaz, D., Freeland, E., Hampton, E., Kewley, L. J., Nikutta, R., Shastri, P., Shu, X., Vogt, F. P., …Woo, J.-H. (2022). The Black Hole–Galaxy Connection: Interplay between Feedback, Obscuration, and Host Galaxy Substructure. Astrophysical Journal, 925(2), Article 203. https://doi.org/10.3847/1538-4357/ac425f

There is growing evidence for physical influence between supermassive black holes and their host galaxies. We present a case study of the nearby galaxy NGC 7582, for which we find evidence that galactic substructure plays an important role in affecti... Read More about The Black Hole–Galaxy Connection: Interplay between Feedback, Obscuration, and Host Galaxy Substructure.

GOODS-ALMA 2.0: Source catalog, number counts, and prevailing compact sizes in 1.1 mm galaxies (2022)
Journal Article
Gómez-Guijarro, C., Elbaz, D., Xiao, M., Béthermin, M., Franco, M., Magnelli, B., Daddi, E., Dickinson, M., Demarco, R., Inami, H., Rujopakarn, W., Magdis, G., Shu, X., Chary, R., Zhou, L., Alexander, D., Bournaud, F., Ciesla, L., Ferguson, H., Finkelstein, S., …Wang, T. (2022). GOODS-ALMA 2.0: Source catalog, number counts, and prevailing compact sizes in 1.1 mm galaxies. Astronomy & Astrophysics, 658, Article A43. https://doi.org/10.1051/0004-6361/202141615

Submillimeter/millimeter observations of dusty star-forming galaxies with the Atacama Large Millimeter/submillimeter Array (ALMA) have shown that dust continuum emission generally occurs in compact regions smaller than the stellar distribution. Howev... Read More about GOODS-ALMA 2.0: Source catalog, number counts, and prevailing compact sizes in 1.1 mm galaxies.

Quasar feedback survey: multiphase outflows, turbulence, and evidence for feedback caused by low power radio jets inclined into the galaxy disc (2022)
Journal Article
Girdhar, A., Harrison, C., Mainieri, V., Bittner, A., Costa, T., Kharb, P., Mukherjee, D., Arrigoni Battaia, F., Alexander, D., Calistro Rivera, G., Circosta, C., De Breuck, C., Edge, A., Farina, E., Kakkad, D., Lansbury, G., Molyneux, S., Mullaney, J., S, S., Thomson, A., & Ward, S. (2022). Quasar feedback survey: multiphase outflows, turbulence, and evidence for feedback caused by low power radio jets inclined into the galaxy disc. Monthly Notices of the Royal Astronomical Society, 512(2), 1608-1628. https://doi.org/10.1093/mnras/stac073

We present a study of a luminous, z = 0.15, type-2 quasar (L[OIII] = 1042.8 erg s−1) from the Quasar Feedback Survey. It is classified as ‘radio-quiet’ (L1.4 GHz = 1023.8 W Hz−1); however, radio imaging reveals ∼ 1 kpc low-power radio jets (Pjet = 10... Read More about Quasar feedback survey: multiphase outflows, turbulence, and evidence for feedback caused by low power radio jets inclined into the galaxy disc.

The Black Hole Mass Function Across Cosmic Times. I. Stellar Black Holes and Light Seed Distribution (2022)
Journal Article
Sicilia, A., Lapi, A., Boco, L., Spera, M., Di Carlo, U. N., Mapelli, M., Shankar, F., Alexander, D. M., Bressan, A., & Danese, L. (2022). The Black Hole Mass Function Across Cosmic Times. I. Stellar Black Holes and Light Seed Distribution. Astrophysical Journal, 924(2), https://doi.org/10.3847/1538-4357/ac34fb

This is the first paper in a series aimed at modeling the black hole (BH) mass function, from the stellar to the intermediate to the (super)massive regime. In the present work, we focus on stellar BHs and provide an ab initio computation of their mas... Read More about The Black Hole Mass Function Across Cosmic Times. I. Stellar Black Holes and Light Seed Distribution.