Ultra Deep Survey

7-year plan

The UDS will image an area of 0.77 sq. degs in the JHK filters to a depth K=23.0, requiring 296 nights of UKIRT time over 7 years. The UDS is a single filled-in WFCAM tile i.e. four WFCAM pointings. The parameters of the survey are summarised in the table below. The UDS Survey Head is Omar Almaini.

7-year plan Filter Area Mag. limit
t(exp.) t(total) Nights
Ultra Deep Survey
J0.7725.0209h 983h296
H24.0174h 818h
K23.058h 271h

The principal goals of the UDS are 1: to determine the epoch of spheroid formation, 2: to produce the first large-volume map of the high-redshift z=3 Universe, 3: to measure the growth of structure and bias since z=3. The science goals are described in detail on the science case page (dated Nov. 2001).

The target field is the Subaru/XMM-Newton Deep Survey (SXDS) field, located at J0218-05. The location of the field is marked in Fig. 1.

Figure 1. Location of the UDS field. The UDS field is the Subaru/XMM-Newton Deep Survey field, which lies at the centre of one of the DXS fields, the XMM-LSS field. The UDS field is marked as the small cherry square within the blue DXS square. The dashed line marks the Galactic plane, and the dotted line marks the ecliptic.

2-year plan

The UKIDSS plan for the first two years of operation is based around an allocation of 290 nights of observing, which is 31% of the 936 nights required to complete the surveys. The UDS will proceed more slowly in the first two years, receiving 62 nights or 21% of the total 296 nights required. The strategy is to cover the full area to full depth in K (23.0), and to image in J to 24.0, one mag. short of the final depth. The parameters of the 2-year plan are summarised in the table below.

2-year plan Filter Area Mag. limit
total nights
Ultra Deep Survey
J0.7724.00.16 620.21