Outputs (4)

The Changing-look Quasar Mrk 590 Is Awakening (2018)
Journal Article
Mathur, S., Denney, K., Gupta, A., Vestergaard, M., De Rosa, G., Krongold, Y., Nicastro, F., Collinson, J., Goad, M., Korista, K., Pogge, R., & Peterson, B. (2018). The Changing-look Quasar Mrk 590 Is Awakening. Astrophysical Journal, 866(2), Article 123. https://doi.org/10.3847/1538-4357/aadd91

Mrk 590 was originally classified as a Seyfert 1 galaxy, but then it underwent dramatic changes: the nuclear luminosity dropped by over two orders of magnitude and the broad emission lines all but disappeared from the optical spectrum. Here we presen... Read More about The Changing-look Quasar Mrk 590 Is Awakening.

The broad-band SEDs of four ‘hypervariable’ AGN (2017)
Journal Article
Collinson, J. S., Ward, M. J., Lawrence, A., Bruce, A., MacLeod, C. L., Elvis, M., …Done, C. (2018). The broad-band SEDs of four ‘hypervariable’ AGN. Monthly Notices of the Royal Astronomical Society, 474(3), 3565-3575. https://doi.org/10.1093/mnras/stx2992

We present an optical-to-X-ray spectral analysis of four ‘hypervariable’ AGN (HVAs) discovered by comparing Pan-STARRS data to that from the Sloan Digital Sky Survey over a 10 yr baseline (Lawrence et al.). There is some evidence that these objects a... Read More about The broad-band SEDs of four ‘hypervariable’ AGN.

Spectral analysis of four ‘hypervariable’ AGN: a micro-needle in the haystack? (2017)
Journal Article
Bruce, A., Lawrence, A., MacLeod, C., Elvis, M., Ward, M., Collinson, J., …Waters, C. (2017). Spectral analysis of four ‘hypervariable’ AGN: a micro-needle in the haystack?. Monthly Notices of the Royal Astronomical Society, 467(2), 1259-1280. https://doi.org/10.1093/mnras/stx168

We analyse four extreme active galactic nuclei (AGN) transients to explore the possibility that they are caused by rare, high-amplitude microlensing events. These previously unknown type-I AGN are located in the redshift range 0.6–1.1 and show change... Read More about Spectral analysis of four ‘hypervariable’ AGN: a micro-needle in the haystack?.

Reaching the peak of the quasar spectral energy distribution – II. Exploring the accretion disc, dusty torus and host galaxy (2016)
Journal Article
Collinson, J. S., Ward, M. J., Landt, H., Done, C., Elvis, M., & McDowell, J. C. (2017). Reaching the peak of the quasar spectral energy distribution – II. Exploring the accretion disc, dusty torus and host galaxy. Monthly Notices of the Royal Astronomical Society, 465(1), 358-382. https://doi.org/10.1093/mnras/stw2666

We continue our study of the spectral energy distributions (SEDs) of 11 active galactic nuclei (AGN) at 1.5 < z < 2.2, with optical–near-infrared (NIR) spectra, X-ray data and mid-IR photometry. In a previous paper, we presented the observations and... Read More about Reaching the peak of the quasar spectral energy distribution – II. Exploring the accretion disc, dusty torus and host galaxy.