Skip to main content

Research Repository

Advanced Search

Professor Leah Morabito's Outputs (108)

Exploring the radio loudness of SDSS quasars with spectral stacking (2024)
Journal Article
Arnaudova, M. I., Smith, D. J. B., Hardcastle, M. J., Das, S., Drake, A., Duncan, K., …Tasse, C. (2024). Exploring the radio loudness of SDSS quasars with spectral stacking. Monthly Notices of the Royal Astronomical Society, 528(3), 4547-4567. https://doi.org/10.1093/mnras/stae233

We use new 144 MHz observations over 5634 deg2 from the LOFAR (Low Frequency Array) Two-metre Sky Survey (LoTSS) to compile the largest sample of uniformly selected, spectroscopically confirmed quasars from the 14th data release of the Sloan Digital... Read More about Exploring the radio loudness of SDSS quasars with spectral stacking.

MIGHTEE: multi-wavelength counterparts in the COSMOS field (2023)
Journal Article
Whittam, I., Prescott, M., Hale, C., Jarvis, M. .., Heywood, I., An, F., …White, S. (2024). MIGHTEE: multi-wavelength counterparts in the COSMOS field. Monthly Notices of the Royal Astronomical Society, 527(2), 3231-3245. https://doi.org/10.1093/mnras/stad3307

In this paper we combine the Early Science radio continuum data from the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) Survey, with optical and near-infrared data and release the cross-matched catalogues. The radio data used in... Read More about MIGHTEE: multi-wavelength counterparts in the COSMOS field.

Subarcsecond-resolution Imaging of M51 with the International LOFAR Telescope (2023)
Journal Article
Venkattu, D., Lundqvist, P., Torres, M. P., Morabito, L., Moldón, J., Conway, J., …Tasse, C. (2023). Subarcsecond-resolution Imaging of M51 with the International LOFAR Telescope. Astrophysical Journal, 953(2), Article 157. https://doi.org/10.3847/1538-4357/ace2c1

We present an International LOFAR Telescope (ILT) subarcsecond-resolution image of the nearby galaxy M51 with a beam size of 0farcs436 × 0farcs366 and rms of 46 μJy. We compare this image with a European VLBI Network study of M51 and discuss the supe... Read More about Subarcsecond-resolution Imaging of M51 with the International LOFAR Telescope.

A Quick Look at the 3 GHz Radio Sky. II. Hunting for DRAGNs in the VLA Sky Survey (2023)
Journal Article
Gordon, Y. A., Rudnick, L., Andernach, H., Morabito, L. K., O’Dea, C. P., Achong, K., …Vantyghem, A. N. (2023). A Quick Look at the 3 GHz Radio Sky. II. Hunting for DRAGNs in the VLA Sky Survey. Astrophysical Journal Supplement, 267(2), Article 37. https://doi.org/10.3847/1538-4365/acda30

Active galactic nuclei (AGNs) can often be identified in radio images as two lobes, sometimes connected to a core by a radio jet. This multicomponent morphology unfortunately creates difficulties for source finders, leading to components that are (a)... Read More about A Quick Look at the 3 GHz Radio Sky. II. Hunting for DRAGNs in the VLA Sky Survey.

VLBI imaging of high-redshift galaxies and protoclusters at low radio frequencies with the International LOFAR Telescope (2023)
Journal Article
Cordun, C. M., Timmerman, R., Miley, G. K., van Weeren, R. J., Sweijen, F., Morabito, L. K., & Röttgering, H. J. A. (2023). VLBI imaging of high-redshift galaxies and protoclusters at low radio frequencies with the International LOFAR Telescope. Astronomy & Astrophysics, 676, Article A29. https://doi.org/10.1051/0004-6361/202346320

It is generally known that luminous, ultra-steep spectrum radio sources are preferentially associated with massive galaxies at high redshifts. In this paper, we describe a pilot project directed at such objects to demonstrate the feasibility and impo... Read More about VLBI imaging of high-redshift galaxies and protoclusters at low radio frequencies with the International LOFAR Telescope.

The LOFAR Two-metre Sky Survey: Deep Fields Data Release 1. V. Survey description, source classifications and host galaxy properties (2023)
Journal Article
Best, P., Kondapally, R., Williams, W., Cochrane, R., Duncan, K., Hale, C., Haskell, P., Małek, K., McCheyne, I., Smith, D., Wang, L., Botteon, A., Bonato, M., Bondi, M., Rivera, G. C., Gao, F., Gürkan, G., Hardcastle, M., Jarvis, M., Mingo, B., …van Weeren, R. (2023). The LOFAR Two-metre Sky Survey: Deep Fields Data Release 1. V. Survey description, source classifications and host galaxy properties. Monthly Notices of the Royal Astronomical Society, 523(2), 1729–1755. https://doi.org/10.1093/mnras/stad1308

Source classifications, stellar masses and star formation rates are presented for ≈80,000 radio sources from the first data release of the Low Frequency Array Two-metre Sky Survey (LoTSS) Deep Fields, which represents the widest deep radio survey eve... Read More about The LOFAR Two-metre Sky Survey: Deep Fields Data Release 1. V. Survey description, source classifications and host galaxy properties.

Identifying Active Galactic Nuclei at z ∼ 3 from the HETDEX Survey Using Machine Learning (2023)
Journal Article
Tardugno Poleo, V., Finkelstein, S. L., Leung, G., Mentuch Cooper, E., Gebhardt, K., Farrow, D. J., Gawiser, E., Zeimann, G., Schneider, D. P., Morabito, L., Mock, D., & Liu, C. (2023). Identifying Active Galactic Nuclei at z ∼ 3 from the HETDEX Survey Using Machine Learning. Astronomical Journal, 165(4), Article 153. https://doi.org/10.3847/1538-3881/acba92

We used data from the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX) to study the incidence of AGN in continuum-selected galaxies at z ∼ 3. From optical and infrared imaging in the 24 deg2 Spitzer HETDEX Exploratory Large Area survey, we cons... Read More about Identifying Active Galactic Nuclei at z ∼ 3 from the HETDEX Survey Using Machine Learning.

Piercing the dusty veil of hyper-luminous infrared galaxies: Sub-arcsecond 144 MHz ILT observations of HLIRGs in the Lockman Hole (2023)
Journal Article
Sweijen, F., Lyu, Y., Wang, L., Gao, F., Röttgering, H., van Weeren, R., Morabito, L., Best, P., Małek, K., Williams, W., Prandoni, I., Bonato, M., & Bondi, M. (2023). Piercing the dusty veil of hyper-luminous infrared galaxies: Sub-arcsecond 144 MHz ILT observations of HLIRGs in the Lockman Hole. Astronomy & Astrophysics, 671, Article A85. https://doi.org/10.1051/0004-6361/202244378

Context. Hyper-luminous infrared galaxies (HLIRGs) are among the most extreme systems in the Universe. With infrared (IR) luminosities of LIR > 1013 L⊙ they can have IR-derived star formation rates (SFRs) exceeding 103 M⊙ yr−1. Theoretical models hav... Read More about Piercing the dusty veil of hyper-luminous infrared galaxies: Sub-arcsecond 144 MHz ILT observations of HLIRGs in the Lockman Hole.

V-LoTSS: The circularly polarised LOFAR Two-metre Sky Survey (2023)
Journal Article
Callingham, J., Shimwell, T., Vedantham, H., Bassa, C., O’Sullivan, S., Yiu, T., Bloot, S., Best, P., Hardcastle, M., Haverkorn, M., Kavanagh, R., Lamy, L., Pope, B., Röttgering, H., Schwarz, D., Tasse, C., van Weeren, R., White, G., Zarka, P., Bomans, D., …Zheng, J. (2023). V-LoTSS: The circularly polarised LOFAR Two-metre Sky Survey. Astronomy & Astrophysics, 670, Article A124. https://doi.org/10.1051/0004-6361/202245567

We present the detection of 68 sources from the most sensitive radio survey in circular polarisation conducted to date. We used the second data release of the 144 MHz LOFAR Two-metre Sky Survey to produce circularly polarised maps with a median noise... Read More about V-LoTSS: The circularly polarised LOFAR Two-metre Sky Survey.

A low-frequency sub-arcsecond view of powerful radio galaxies in rich-cluster environments: 3C 34 and 3C 320 (2023)
Journal Article
Mahatma, V., Basu, A., Hardcastle, M., Morabito, L., & van Weeren, R. (2023). A low-frequency sub-arcsecond view of powerful radio galaxies in rich-cluster environments: 3C 34 and 3C 320. Monthly Notices of the Royal Astronomical Society, 520(3), 4427-4442. https://doi.org/10.1093/mnras/stad395

Models of radio galaxy physics have been primarily based on high frequency (≥1 GHz) observations of their jets, hotspots, and lobes. Without highly resolved low-frequency observations, which provide information on older plasma, our understanding of t... Read More about A low-frequency sub-arcsecond view of powerful radio galaxies in rich-cluster environments: 3C 34 and 3C 320.

Measuring cavity powers of active galactic nuclei in clusters using a hybrid X-ray–radio method. A new window on feedback opened by subarcsecond LOFAR-VLBI observations (2022)
Journal Article
Timmerman, R., van Weeren, R., Botteon, A., Röttgering, H., McNamara, B., Sweijen, F., Bîrzan, L., & Morabito, L. (2022). Measuring cavity powers of active galactic nuclei in clusters using a hybrid X-ray–radio method. A new window on feedback opened by subarcsecond LOFAR-VLBI observations. Astronomy & Astrophysics, 668, Article A65. https://doi.org/10.1051/0004-6361/202243936

Measurements of the quantity of radio-mode feedback injected by an active galactic nucleus into the cluster environment have mostly relied on X-ray observations, which reveal cavities in the intracluster medium excavated by the radio lobes. However,... Read More about Measuring cavity powers of active galactic nuclei in clusters using a hybrid X-ray–radio method. A new window on feedback opened by subarcsecond LOFAR-VLBI observations.

MIGHTEE: deep 1.4 GHz source counts and the sky temperature contribution of star-forming galaxies and active galactic nuclei (2022)
Journal Article
Hale, C., Whittam, I., Jarvis, M., Best, P., Thomas, N., Heywood, I., Prescott, M., Adams, N., Afonso, J., An, F., Bowler, R., Collier, J., Cook, R., Davé, R., Frank, B., Glowacki, M., Hatfield, P., Kolwa, S., Lovell, C., Maddox, N., …Taylor, A. (2023). MIGHTEE: deep 1.4 GHz source counts and the sky temperature contribution of star-forming galaxies and active galactic nuclei. Monthly Notices of the Royal Astronomical Society, 520(2), 2668 - 2691. https://doi.org/10.1093/mnras/stac3320

We present deep 1.4 GHz source counts from ∼5 deg2 of the continuum Early Science data release of the MeerKAT International Gigahertz Tiered Extragalactic Exploration survey down to S1.4GHz ∼15 μ Jy. Using observations over two extragalactic fields (... Read More about MIGHTEE: deep 1.4 GHz source counts and the sky temperature contribution of star-forming galaxies and active galactic nuclei.

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.

MIGHTEE: the nature of the radio-loud AGN population (2022)
Journal Article
Whittam, I., Jarvis, M., Hale, C., Prescott, M., Morabito, L., Heywood, I., Adams, N., Afonso, J., An, F., Ao, Y., Bowler, R., Collier, J., Deane, R., Delhaize, J., Frank, B., Glowacki, M., Hatfield, P., Maddox, N., Marchetti, L., Matthews, A., …Vaccari, M. (2022). MIGHTEE: the nature of the radio-loud AGN population. Monthly Notices of the Royal Astronomical Society, 516(1), 245-263. https://doi.org/10.1093/mnras/stac2140

We study the nature of the faint radio source population detected in the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) Early Science data in the COSMOS field, focusing on the properties of the radio-loud active galactic nuclei... Read More about MIGHTEE: the nature of the radio-loud AGN population.

Identifying active galactic nuclei via brightness temperature with sub-arcsecond international LOFAR Telescope observations (2022)
Journal Article
Morabito, L. K., Sweijen, F., Radcliffe, J., Best, P., Kondapally, R., Bondi, M., Bonato, M., Duncan, K., Prandoni, I., Shimwell, T., Williams, W., van Weeren, R., Conway, J., & Rivera, G. C. (2022). Identifying active galactic nuclei via brightness temperature with sub-arcsecond international LOFAR Telescope observations. Monthly Notices of the Royal Astronomical Society, 515(4), 5758-5774. https://doi.org/10.1093/mnras/stac2129

Identifying active galactic nuclei (AGNs) and isolating their contribution to a galaxy’s energy budget is crucial for studying the co-evolution of AGNs and their host galaxies. Brightness temperature (Tb) measurements from high-resolution radio obser... Read More about Identifying active galactic nuclei via brightness temperature with sub-arcsecond international LOFAR Telescope observations.

Seeing the forest and the trees: a radio investigation of the ULIRG Mrk 273 (2022)
Journal Article
Kukreti, P., Morganti, R., Bondi, M., Oosterloo, T., Tadhunter, C., Morabito, L. K., Adams, E., Adebahr, B., de Blok, W., de Gasperin, F., Drabent, A., Hess, K., Ivashina, M., Kutkin, A., Mika, Á. M., Oostrum, L., Shimwell, T., van der Hulst, J., van Leeuwen, J., van Weeren, R., …Ziemke, J. (2022). Seeing the forest and the trees: a radio investigation of the ULIRG Mrk 273. Astronomy & Astrophysics, 664, Article A25. https://doi.org/10.1051/0004-6361/202243174

Galaxy mergers have been observed to trigger nuclear activity by feeding gas to the central supermassive black hole. One such class of objects are Ultra Luminous InfraRed Galaxies (ULIRGs), which are mostly late stage major mergers of gas-rich galaxi... Read More about Seeing the forest and the trees: a radio investigation of the ULIRG Mrk 273.

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.

Subarcsecond view on the high-redshift blazar GB 1508+5714 by the International LOFAR Telescope (2022)
Journal Article
Kappes, A., Burd, P., Kadler, M., Ghisellini, G., Perucho, M., Brüggen, M., Cheung, C., Ciardi, B., Gallo, E., Haardt, F., Morabito, L., Sbarrato, T., Bonnassieux, E., Drabent, A., Harwood, J., Jackson, N., & Moldon, J. (2022). Subarcsecond view on the high-redshift blazar GB 1508+5714 by the International LOFAR Telescope. Astronomy & Astrophysics, 663, Article A44. https://doi.org/10.1051/0004-6361/202141720

Context. Studies of the most distant active galactic nuclei (AGNs) allow us to test our current understanding of the physics present in radio-jetted AGNs across a range of environments, and probe their interactions with these environments. The decrea... Read More about Subarcsecond view on the high-redshift blazar GB 1508+5714 by the International LOFAR Telescope.

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.