UKIDSS

The UKIRT Infrared Deep Sky Survey ( UKIDSS ) is an astronomical survey of the sky . It is carried out by the UKIRT's WFCAM camera on Mauna Kea in Hawaii . The survey was started in 2005. UKIDSS consists of five different explorations covering different areas and depths, using different combinations of near infrared filters. In addition to the 5 broadband filters Z, Y, J, H and K, 2 narrowband filters are used. The Z filter was manufactured by Research Electronic Inc. The other filters come from NDC Infrared Engineering.

description

As a long-range research, UKIDSS follows the 2MASS project. The OBJECTIVE is to study 7500 square degrees of the northern sky. The individual research areas are: The coldest and closest brown dwarfs , starburst galaxies with a high redshift , elliptical galaxies and galaxy clusters with a redshift 1 <z <2 and quasars with the highest redshift.

The UKIDSS data is immediately put online for the ESO community via entry in the WFCAM Science Archive. After 18 months will be made publicly available.

Explorations

Two of the UKIDSS researches are aimed at galactic targets and three are optimized for extra-galactic observations.

Large Area Survey

The LAS (extra galactic) covers an area of 4000 square degrees in YJHK to a depth of K = 18.4 (this is the largest still recognizable magnitude in the K band , a wavelength range of the near infrared at 2.2 µm). This area was already searched in the optical area during the previous SLOAN Digital Sky Survey . While the higher galactic latitudes searched by LAS are suitable for observations from sources outside the Milky Way, the exploration also aims at galactic sources including a second pass in J for measuring the proper motion of nearby stars.

Galactic Plane Survey (GPS)

The Galactic Plane Survey (galactic) covers 1800 square degrees in JHK at a depth of K = 19.0, of which 300 square degrees are covered by a narrow-band H ₂ filter. The intention of GPS is to get a better view of the Milky Way than is possible with optical wavelengths because of the absorption by matter in the galaxy.

Galactic Clusters Survey (GCS)

The GCS (galactic) covers an area of 1400 square degrees in JHK to a depth of K = 18.7. The area is distributed over 10 open star clusters . The aim is to measure the mass function in a selection of galactic environments. The ten star clusters are the Pleiades , Alpha Persei , Praesepe , IC 4665, Taurus-Auriga, Orion , Scorpio , Perseus OB2 , Hyaden , Coma-Ber

Deep Extragalactic Survey

The DXS (extra galactic) covers an area of 35 square degrees in JK to a depth of K = 21.0 with 5 square degrees recorded in H. The exploration fields are located in the upper galactic latitudes with a lower extinction. They overlap with other depth explorations made with different wavelengths.

Ultra Deep Survey

The UDS (extra galactic) covers an area of 0.77 square degrees in the XMM-Newton field. With a depth of K = 23.0, it is the deepest exploration in the near infrared range that has been carried out in such an area of the sky. The aim is to study the formation and evolution of galaxies in the early universe.

Important discoveries

Wolf 940 B A brown dwarf which, with a surface temperature of 600 Kelvin, is one of the coldest substellar objects.
ULAS J1120 + 0641 With approx. 13 billion light years the most distant quasar.