A DUAL-BAND MILLIMETER-WAVE KINETIC INDUCTANCE CAMERA FOR THE IRAM 30 m TELESCOPE

Abstract

Context. The Neel IRAM KIDs Array (NIKA) is a fully-integrated measurement\nsystem based on kinetic inductance detectors (KIDs) currently being developed\nfor millimeter wave astronomy. In a first technical run, NIKA was successfully\ntested in 2009 at the Institute for Millimetric Radio Astronomy (IRAM) 30-meter\ntelescope at Pico Veleta, Spain. This prototype consisted of a 27-42 pixel\ncamera imaging at 150 GHz. Subsequently, an improved system has been developed\nand tested in October 2010 at the Pico Veleta telescope. The instrument\nupgrades included dual-band optics allowing simultaneous imaging at 150 GHz and\n220 GHz, faster sampling electronics enabling synchronous measurement of up to\n112 pixels per measurement band, improved single-pixel sensitivity, and the\nfabrication of a sky simulator to replicate conditions present at the\ntelescope. Results. The new dual-band NIKA was successfully tested in October\n2010, performing in-line with sky simulator predictions. Initially the sources\ntargeted during the 2009 run were re-imaged, verifying the improved system\nperformance. An optical NEP was then calculated to be around 2 \\dot 10-16\nW/Hz1/2. This improvement in comparison with the 2009 run verifies that NIKA is\napproaching the target sensitivity for photon-noise limited ground-based\ndetectors. Taking advantage of the larger arrays and increased sensitivity, a\nnumber of scientifically-relevant faint and extended objects were then imaged\nincluding the Galactic Center SgrB2(FIR1), the radio galaxy Cygnus A and the\nNGC1068 Seyfert galaxy. These targets were all observed simultaneously in the\n150 GHz and 220 GHz atmospheric windows.\n