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تسجيل مستخدم جديدThe Far-Infrared-Radio Correlation in MS0451-03
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نشر من قبل
Solohery Mampionona Randriamampandry
تاريخ النشر
2014
مجال البحث
فيزياء
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English
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We present a multi-wavelength analysis of star-forming galaxies in the massive cluster MS0451.6-0305 at z $sim$ 0.54 to shed new light on the evolution of the far-infrared-radio relationship in distant rich clusters. We have derived total infrared luminosities for a spectroscopically confirmed sample of cluster and field galaxies through an empirical relation based on $Spitzer$ MIPS 24 $mu$m photometry. The radio flux densities were measured from deep Very Large Array 1.4 GHz radio continuum observations. We find the ratio of far-infrared to radio luminosity for galaxies in an intermediate redshift cluster to be $q_{rm FIR}$ = 1.80$pm$0.15 with a dispersion of 0.53. Due to the large intrinsic dispersion, we do not find any observable change in this value with either redshift or environment. However, a higher percentage of galaxies in this cluster show an excess in their radio fluxes when compared to low redshift clusters ($27^{+23}_{-13}%$ to $11%$), suggestive of a cluster enhancement of radio-excess sources at this earlier epoch. In addition, the far-infrared-radio relationship for blue galaxies, where $q_{rm FIR}$ = 2.01$pm$0.14 with a dispersion of 0.35, is consistent with the predicted value from the field relationship, although these results are based on a sample from a single cluster.
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