Discovery of a lensed ultrabright submillimeter galaxy at z=2.0439

Resumen

We report an ultra-bright lensed submillimeter galaxy (SMG) at z = 2.0439, WISEJ132934.18+224327.3, identified as a result of a full-sky cross-correlation of the AllWISEand Planck compact source catalogs aimed to search for bright analogs of the submillimetergalaxy SMMJ2135, the Cosmic Eyelash. Inspection of archival SCUBA-2 observations ofthe candidates revealed a source with fluxes (S850µm= 130 mJy) consistent with the Planckmeasurements. The centroid of the SCUBA-2 source coincides within 1 arcsec with theposition of the AllWISE mid-IR source, and, remarkably, with an arc shaped lensed galaxyin HST images at visible wavelengths. Low-resolution rest-frame UV-optical spectroscopyof this lensed galaxy obtained with 10.4 m GTC reveals the typical absorption lines of astarburst galaxy. Gemini-N near-IR spectroscopy provided a clear detection of Hα emission.The lensed source appears to be gravitationally magnified by a massive foreground galaxycluster lens at z = 0.44, modeling with Lenstool indicates a lensing amplification factor of11±2. We determine an intrinsic rest-frame 8-1000-µm luminosity, LIR, of (1.3±0.1)×1013L , and a likely star-formation rate (SFR) of ∼ 500−2000 M yr−1. The SED shows a remarkable similarity with the Cosmic Eyelash from optical-mid/IR to sub-millimeter/radio,albeit at higher fluxes.