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تسجيل مستخدم جديدFar-infrared spectroscopy of a lensed starburst: a blind redshift from Herschel
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We report the redshift of HATLAS J132427.0+284452 (hereafter HATLAS J132427), a gravitationally lensed starburst galaxy, the first determined blind by the Herschel Space Observatory. This is achieved via the detection of [C II] consistent with z = 1.68 in a far-infrared spectrum taken with the SPIRE Fourier Transform Spectrometer. We demonstrate that the [C II] redshift is secure via detections of CO J = 2 - 1 and 3 - 2 using the Combined Array for Research in Millimeter-wave Astronomy and the Institut de Radioastronomie Millimetriques Plateau de Bure Interferometer. The intrinsic properties appear typical of high-redshift starbursts despite the high lensing-amplified fluxes, proving the ability of the FTS to probe this population with the aid of lensing. The blind detection of [C II] demonstrates the potential of the SAFARI imaging spectrometer, proposed for the much more sensitive SPICA mission, to determine redshifts of multiple dusty galaxies simultaneously without the benefit of lensing.
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The most intensively star-forming galaxies are extremely luminous at far-infrared (FIR) wavelengths, highly obscured at optical and ultraviolet wavelengths, and lie at $zge 1-3$. We present a programme of ${it Herschel}$ FIR spectroscopic observation
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