Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes
Ultra Steep Spectrum (USS) radio sources have been successfully used to select powerful radio sources at high redshifts (z > 2). Typically restricted to large-sky surveys and relatively bright radio flux densities, it has gradually become possible to extend the USS search to sub-mJy levels, thank...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , |
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| Format: | Conference Paper |
| Published: |
2012
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| Online Access: | http://hdl.handle.net/20.500.11937/17479 |
| _version_ | 1848749477156880384 |
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| author | Bizzocchi, L. Afonso, J. Ibar, E. Grossi, M. Simpson, C. Chapman, S. Jarvis, M. Rottgering, H. Norris, R. Dunlop, J. Ivison, R. Messias, H. Pforr, J. Vaccari, M. Seymour, Nick Best, P. Gonz, E. Farrah, D. Huang, J. Lacy, M. Marastron, C. Marchetti, L. Mauduit, J. Oliver, S. Rigopoulou, D. Stanford, S. Surace, J. Zeimann, G. |
| author_facet | Bizzocchi, L. Afonso, J. Ibar, E. Grossi, M. Simpson, C. Chapman, S. Jarvis, M. Rottgering, H. Norris, R. Dunlop, J. Ivison, R. Messias, H. Pforr, J. Vaccari, M. Seymour, Nick Best, P. Gonz, E. Farrah, D. Huang, J. Lacy, M. Marastron, C. Marchetti, L. Mauduit, J. Oliver, S. Rigopoulou, D. Stanford, S. Surace, J. Zeimann, G. |
| author_sort | Bizzocchi, L. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Ultra Steep Spectrum (USS) radio sources have been successfully used to select powerful radio sources at high redshifts (z > 2). Typically restricted to large-sky surveys and relatively bright radio flux densities, it has gradually become possible to extend the USS search to sub-mJy levels, thanks to the recent appearance of sensitive low-frequency radio facilities. Here we present a first detailed analysis of the nature of the faintest USS sources. By using GMRT and VLA radio observations of the Lockman Hole (LH) at 610MHz and 1.4GHz, a sample of 58 micro-Jansky USS sources is assembled. Deep infrared data at 3.6 and 4.5µm from the Spitzer Extragalactic Representative Volume Survey (SERVS) is used to reliably identify counterparts for 48 (83%) of these sources, showing an average magnitude of [3.6]=19.7 mag(AB). Spectroscopic redshifts for 14 USS sources, together with photometric redshift estimates, improved by the use of the deep SERVS data, for a further 19 objects, show redshifts ranging from z =0.1 to z=2.8, peaking at z~0.6 and tailing off at high redshifts. |
| first_indexed | 2025-11-14T07:21:33Z |
| format | Conference Paper |
| id | curtin-20.500.11937-17479 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:21:33Z |
| publishDate | 2012 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-174792018-03-29T09:06:20Z Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes Bizzocchi, L. Afonso, J. Ibar, E. Grossi, M. Simpson, C. Chapman, S. Jarvis, M. Rottgering, H. Norris, R. Dunlop, J. Ivison, R. Messias, H. Pforr, J. Vaccari, M. Seymour, Nick Best, P. Gonz, E. Farrah, D. Huang, J. Lacy, M. Marastron, C. Marchetti, L. Mauduit, J. Oliver, S. Rigopoulou, D. Stanford, S. Surace, J. Zeimann, G. Ultra Steep Spectrum (USS) radio sources have been successfully used to select powerful radio sources at high redshifts (z > 2). Typically restricted to large-sky surveys and relatively bright radio flux densities, it has gradually become possible to extend the USS search to sub-mJy levels, thanks to the recent appearance of sensitive low-frequency radio facilities. Here we present a first detailed analysis of the nature of the faintest USS sources. By using GMRT and VLA radio observations of the Lockman Hole (LH) at 610MHz and 1.4GHz, a sample of 58 micro-Jansky USS sources is assembled. Deep infrared data at 3.6 and 4.5µm from the Spitzer Extragalactic Representative Volume Survey (SERVS) is used to reliably identify counterparts for 48 (83%) of these sources, showing an average magnitude of [3.6]=19.7 mag(AB). Spectroscopic redshifts for 14 USS sources, together with photometric redshift estimates, improved by the use of the deep SERVS data, for a further 19 objects, show redshifts ranging from z =0.1 to z=2.8, peaking at z~0.6 and tailing off at high redshifts. 2012 Conference Paper http://hdl.handle.net/20.500.11937/17479 10.1007/978-3-642-22795-0_10 restricted |
| spellingShingle | Bizzocchi, L. Afonso, J. Ibar, E. Grossi, M. Simpson, C. Chapman, S. Jarvis, M. Rottgering, H. Norris, R. Dunlop, J. Ivison, R. Messias, H. Pforr, J. Vaccari, M. Seymour, Nick Best, P. Gonz, E. Farrah, D. Huang, J. Lacy, M. Marastron, C. Marchetti, L. Mauduit, J. Oliver, S. Rigopoulou, D. Stanford, S. Surace, J. Zeimann, G. Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes |
| title | Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes |
| title_full | Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes |
| title_fullStr | Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes |
| title_full_unstemmed | Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes |
| title_short | Ultra steep spectrum radio sources in the Lockman Hole: SERVS identifications and redshift distribution at the faintest radio fluxes |
| title_sort | ultra steep spectrum radio sources in the lockman hole: servs identifications and redshift distribution at the faintest radio fluxes |
| url | http://hdl.handle.net/20.500.11937/17479 |