eprintid: 1387398 rev_number: 39 eprint_status: archive userid: 608 dir: disk0/01/38/73/98 datestamp: 2013-03-06 19:35:04 lastmod: 2021-09-26 22:45:05 status_changed: 2018-03-05 12:56:37 type: article metadata_visibility: show item_issues_count: 0 creators_name: Rawlings, JI creators_name: Seymour, N creators_name: Page, MJ creators_name: De Breuck, C creators_name: Stern, D creators_name: Symeonidis, M creators_name: Appleton, PN creators_name: Dey, A creators_name: Dickinson, M creators_name: Huynh, M creators_name: Le Floc'h, E creators_name: Lehnert, M creators_name: Mullaney, JR creators_name: Nesvadba, N creators_name: Ogle, P creators_name: Sajina, A creators_name: Vernet, J creators_name: Zirm, A title: Polycyclic aromatic hydrocarbon emission in powerful high-redshift radio galaxies ispublished: pub divisions: UCL divisions: B04 divisions: C06 divisions: F63 keywords: Galaxies: active, galaxies: high-redshift, galaxies: nuclei, quasars: general, galaxies: star formation, ACTIVE GALACTIC NUCLEI, ULTRALUMINOUS INFRARED GALAXIES, SPITZER-SPACE-TELESCOPE, STAR-FORMING GALAXIES, MOLECULAR-HYDROGEN EMISSION, SUPERMASSIVE BLACK-HOLES, M SILICATE ABSORPTION, EXTENDED IONIZED-GAS, DEEP FIELD-SOUTH, AGN DUSTY TORI note: This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions. abstract: We present the mid-infrared (IR) spectra of seven of the most powerful radio-galaxies known to exist at 1.5 < z < 2.6. The radio emission of these sources is dominated by the AGN with 500 MHz luminosities in the range 1027.8–1029.1 W Hz−1. The AGN signature is clearly evident in the mid-IR spectra; however, we also detect polycyclic aromatic hydrocarbon emission, indicative of prodigious star formation at a rate of up to ∼1000 M yr−1. Interestingly, we observe no significant correlation between AGN power and star formation in the host galaxy. We also find most of these radio galaxies to have weak 9.7 µm silicate absorption features (τ9.7 µm < 0.8) which implies that their mid-IR obscuration is predominantly due to the dusty torus that surrounds the central engine, rather than the host galaxy. The tori are likely to have an inhomogeneous distribution with the obscuring structure consisting of individual clouds. We estimate that these radio galaxies have already formed the bulk of their stellar mass and appear to lie at a stage in their evolution where the obscured AGN dominates the energy output of the system but star formation is also prevalent. date: 2013-02-01 date_type: published publisher: OXFORD UNIV PRESS official_url: http://dx.doi.org/10.1093/mnras/sts368 vfaculties: VMPS oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green article_type_text: Article verified: verified_manual elements_source: Scopus elements_id: 855078 doi: 10.1093/mnras/sts368 lyricists_name: Page, Mathew lyricists_name: Rawlings, Jason lyricists_name: Symeonidis, Myrto lyricists_id: MJPAG55 lyricists_id: JIRAW97 lyricists_id: MSYME08 actors_name: Dewerpe, Marie actors_id: MDDEW97 actors_role: owner full_text_status: public publication: Monthly Notices of the Royal Astronomical Society volume: 429 number: 1 pagerange: 744-756 pages: 13 issn: 0035-8711 citation: Rawlings, JI; Seymour, N; Page, MJ; De Breuck, C; Stern, D; Symeonidis, M; Appleton, PN; ... Zirm, A; + view all <#> Rawlings, JI; Seymour, N; Page, MJ; De Breuck, C; Stern, D; Symeonidis, M; Appleton, PN; Dey, A; Dickinson, M; Huynh, M; Le Floc'h, E; Lehnert, M; Mullaney, JR; Nesvadba, N; Ogle, P; Sajina, A; Vernet, J; Zirm, A; - view fewer <#> (2013) Polycyclic aromatic hydrocarbon emission in powerful high-redshift radio galaxies. Monthly Notices of the Royal Astronomical Society , 429 (1) pp. 744-756. 10.1093/mnras/sts368 <https://doi.org/10.1093/mnras%2Fsts368>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/1387398/1/Symeonidis_sts368.pdf