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UDF Parallels - General Information

UDF parallel observations have been obtained with NICMOS (F110W and F160W), WFPC2 (F300W), STIS (50CCD + MIRROR imaging and 50CCD + G750L slitless spectroscopy), and ACS/HRC (F220W, F555W, F892N, G800L). For more on each of these programs, please click on the link for that instrument.

The deepest part of the NICMOS images should be the deepest near-infrared imaging ever done if the anticipated depths were achieved. The observations were done in two extended observing campaigns or Epochs of about six weeks each between September 2003 and January 2004. A layout of the parallel fields may be seen below, and is also available as a PDF file.


Fields Overlay Diagram: Layout of the ACS UDF and NICMOS UDF with their respective parallels. A more detailed description is available.

By design, the greater part of the observations have been done at one of two ORIENT angles in both of the two observing epochs, but by necessity, in order to accommodate the observations within the same general time frame and to also allow other GO observations to schedule, a smaller number of observations were done at a second ORIENT angle since that allowed for scheduling over a larger number of days within the larger UDF period. In Epoch 1, the largest amount of time was spent at ORIENT 314. In Epoch 2, the largest amount of time was spent at ORIENT 44. The tables below summarize approximate exposure time totals achieved.

The NICMOS parallel observations are intended to be released at the same time as the primary ACS UDF observations. The WFPC2 and STIS UDF parallel observations became public immediately upon their entry into the archive. For more details on data release timing and plans, please see the primary ACS UDF web pages.

Read more background details on the rationale behind UDF parallels design and scheduling here...

Epoch 1:

Observations have now been completed, and approximate exposure time totals are below (summed from Preliminary Observing Timeline Report files except for ACS/HRC, which are totals from the data). NICMOS total exposure times summed from the data are also available and are slightly different from the values below.

NICMOS

Epoch 1

Orient 310 Orient 314 Total in Overlap Region (~1/4 NIC3 Field)
F110W 46014.47s 150715.11s 196729.58s
F160W 49598.30s 160250.73s 209849.03s


WFPC2

Epoch 1

Orient 310 Orient 314 Total in Overlap Region (most of chevron)
F300W 84700s 238400s 323100s


STIS

Epoch 1

Orient 310 Orient 314 Total in Overlap Region (just small edge)
MIRROR 2700s 8500s 11200s
G750L 65898s 214634s 280532s


ACS/HRC

Epoch 1

Orient 310 Orient 314 Total in Overlap Region (~1/2 HRC Field)
F220W 13308s 48796s 62104s
F555W 17744s 45454s 63198s
F892N 39924s 128644s 168568s
G800L 39924s 124208s 164132s

Epoch 2:

Observations have now been completed, and approximate exposure time totals are below (summed from Preliminary Observing Timeline Report files except for ACS/HRC, which are totals from the data). NICMOS total exposure times summed from the data are also available and are slightly different from the values below.

NICMOS

Epoch 2

Orient 40 Orient 44 Total in Overlap Region (~1/4 NIC3 Field)
F110W 36606.80s 137659.48s 174266.28s
F160W 39806.68s 150203.01s 190009.69s


WFPC2

Epoch 2

Orient 40 Orient 44 Total in Overlap Region (most of Chevron)
F300W 65800s 213100s 278900s


STIS

Epoch 2

Orient 40 Orient 44 Total in Overlap Region (just small edge)
MIRROR 2600s 8800s 11400s
G750L 64117s 174202s 238319s


ACS/HRC

Epoch 2

Orient 40 Orient 44 Total in Overlap Region (~1/2 HRC Field)
F220W 8872s 43560s 52432s
F555W 17744s 39124s 56868s
F892N 31052s 104264s 135316s
G800L 31052s 104264s 135316s

Weekly Preliminary Observation Timeline Reports for the UDF showing the Parallels' Association with the ACS Primaries may be seen below.
Note: No parallels were taken with program ID 10086.

Epoch 1:

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6
9978 9978 9978 9978 9978 9978
9979 9979 9979 9979 9979 9979
9980 9980 9980 9980 9980 9980
9981 9981 9981 9981 9981 9981

Some "stray" WFPC2 and STIS parallels:
9980
9981

Epoch 2:

Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7
9978 9978 9978 9978 9978 9978 9978
9979 9979 9979 9979 9979 9979 9979
9980 9980 9980 9980 9980 9980 9980
9981 9981 9981 9981 9981 9981 9981
10086 10086 10086 10086 10086 10086 10086