The far-infrared/radio correlation as probed by Herschel
Titre | The far-infrared/radio correlation as probed by Herschel |
Type de publication | Journal Article |
Year of Publication | 2010 |
Auteurs | Ivison, RJ, Magnelli, B, Ibar, E, Andreani, P, Elbaz, D, Altieri, B, Amblard, A, Arumugam, V, Auld, R, Aussel, H, Babbedge, T, Berta, S, Blain, A, Bock, J, Bongiovanni, A, Boselli, A, Buat, V, Burgarella, D, Castro-Rodriguez, N, Cava, A, Cepa, J, Chanial, P, Cimatti, A, Cirasuolo, M, Clements, DL, Conley, A, Conversi, L, Cooray, A, Daddi, E, Dominguez, H, Dowell, CD, Dwek, E, Eales, S, Farrah, D, Schreiber, NF, Fox, M, Franceschini, A, Gear, W, Genzel, R, Glenn, J, Griffin, M, Gruppioni, C, Halpern, M, Hatziminaoglou, E, Isaak, K, Lagache, G, Levenson, L, Lu, N, Lutz, D, Madden, S, Maffei, B, Magdis, G, Mainetti, G, Maiolino, R, Marchetti, L, Morrison, GE, Mortier, AMJ, Nguyen, HT, Nordon, R, O'Halloran, B, Oliver, SJ, Omont, A, Owen, FN, Page, MJ, Panuzzo, P, Papageorgiou, A, Pearson, CP, Perez-Fournon, I, Garcia, AMP, Poglitsch, A, Pohlen, M, Popesso, P, Pozzi, F, Rawlings, JI, Raymond, G, Rigopoulou, D, Riguccini, L, Rizzo, D, Rodighiero, G, Roseboom, IG, Rowan-Robinson, M, Saintonge, A, Portal, MS, Santini, P, Schulz, B, Scott, D, Seymour, N, Shao, L, Shupe, DL, Smith, AJ, Stevens, JA, Sturm, E, Symeonidis, M, Tacconi, L, Trichas, M, Tugwell, KE, Vaccari, M, Valtchanov, I, Vieira, J, Vigroux, L, Wang, L, Ward, R, Wright, G, Xu, CK, Zemcov, A |
Journal | Astronomy & Astrophysics |
Volume | 518 |
Date Published | Jul-Aug |
ISBN Number | 0004-6361 |
Numéro d'accès | WOS:000281527200032 |
Résumé | We set out to determine the ratio, q(IR), of rest-frame 8-1000-mu m flux, S(IR), to monochromatic radio flux, S 1.4 GHz, for galaxies selected at far-infrared (IR) and radio wavelengths, to search for signs that the ratio evolves with redshift, luminosity or dust temperature, T(d), and to identify any far-IR-bright outliers - useful laboratories for exploring why the far-IR/radio correlation (FIRRC) is generally so tight when the prevailing theory suggests variations are almost inevitable. We use flux-limited 250-mu m and 1.4-GHz samples, obtained using Herschel and the Very Large Array (VLA) in GOODS-North (-N). We determine bolometric IR output using ten bands spanning lambda(obs) = 24-1250 mu m, exploiting data from PACS and SPIRE (PEP; HerMES), as well as Spitzer, SCUBA, AzTEC and MAMBO. We also explore the properties of an L(IR)-matched sample, designed to reveal evolution of q(IR) with redshift, spanning log L(IR) = 11-12 L(circle dot) and z = 0-2, by stacking into the radio and far-IR images. For 1.4-GHz-selected galaxies in GOODS-N, we see tentative evidence of a break in the flux ratio, q(IR), at L(1.4 GHz) similar to 10(22.7) WHz(-1), where active galactic nuclei (AGN) are starting to dominate the radio power density, and of weaker correlations with redshift and T(d). From our 250-mu m-selected sample we identify a small number of far-IR-bright outliers, and see trends of q(IR) with L1.4 GHz, L(IR), T(d) and redshift, noting that some of these are inter-related. For our L(IR)-matched sample, there is no evidence that q(IR) changes significantly as we move back into the epoch of galaxy formation: we find q(IR) proportional to (1+ z)(gamma), where gamma = -0.04 +/- 0.03 at z = 0 -2; however, discounting the least reliable data at z < 0.5 we find gamma = -0.26 +/- 0.07, modest evolution which may be related to the radio background seen by ARCADE 2, perhaps driven by < 10-mu Jy radio activity amongst ordinary star-forming galaxies at z > 1. |