The Far-Infrared Deep Extragalactic Legacy Survey (FIDEL)
Spitzer Legacy Data Products
Second Spitzer Data Release (DR2)

Document version: 14 September 2007


1.0 General Information

This document describes the second release of data products from the Far-Infrared Deep Extragalactic Legacy Survey (FIDEL), a Spitzer Space Telescope Legacy Science program (PI: Mark Dickinson, NOAO).

This data release (DR2) consists of observations for all three FIDEL survey fields:

The data were taken with the Multiband Imaging Photometry for Spitzer (MIPS, Rieke et al. 2004): The data products are being delivered to the Spitzer Science Center (SSC) for public release in September 2007. These are "best-effort", preliminary reductions that the FIDEL team is releasing on a short time scale in order to facilitate investigations by the broader astronomical community. DR2 provides data for all three FIDEL fields prior to the last opportunity to propose for Spitzer cryogenic observations, in GO-5.

The imaging data products are described in detail below, and consist of a science image mosaic at each wavelength plus associated exposure and noise maps.

2.0 Observations

FIDEL is Spitzer program ID (PID) number 30948, and was originally submitted with the title "A Deep-Wide Far-Infrared Survey of Cosmological Star Formation and AGN Activity." The program is obtaining data in three fields on the sky. Most of the data come from two fields, the Extended Chandra Deep Field South (ECDFS) and the Extended Groth Strip (EGS). Additional data are also being obtained in the GOODS-North area, in order to augment partial 70 micron coverage of that field from a GO-1 program (PID 3325, see Frayer et al. 2006b, ApJ, 647, L9). The observing strategies and data reduction are different for the three fields, and we discuss them each separately below.

Spitzer MIPS observations are now organized into "warm" and "cold" campaigns, in order to maximize the cryogenic lifetime of the telescope. "Cold" campaigns result in greater cryogen usage, and provide a lower background to allow 160 micron observations to be taken. The only cold campaign 160 micron data for FIDEL that have been reduced so far are those for EGS epoch 1, which are presented here.

The design of the AORs for the FIDEL MIPS observations is somewhat complex, and we will only give a high-level description here. Please refer to the Spitzer Observer's Manual for detailed explanations of the various observing modes and terminology. The target coordinates observing dates for the MIPS observations used in this data release are summarized in Table 1, which also provides links to detailed information about the AORs that make up each block of observations.

Table 1 - MIPS observations used in data release DR2

Observation Spitzer program ID RA (J2000) Dec (J2000) Start date End date AOR summary
ECDFS FIDEL epoch 1 photometry mode 30948 03:32:30.37 -27:48:19.3 2006-09-01 2006-09-05 AORs
ECDFS FIDEL epoch 2 photometry mode 30948 03:32:30.37 -27:48:19.3 2007-03-01 2007-03-07 AORs
GOODS-N FIDEL photometry mode 30948 12:36:58.41 +62:14:41.1 2006-12-04 2006-12-06 AORs
EGS FIDEL epoch 1 scan mode 30948 14:20:05.0 +52:58:00.0 2007-01-14 2007-01-18 AORs
EGS GTO first observation, scan mode 00008 14:19:00.0 +52:46:00.0 2003-12-28 2003-12-30 AORs
EGS GTO second observation, scan mode 00008 14:19:00.0 +52:46:00.0 2004-06-19 2004-06-20 AORs

3.0 Data Reduction

DR2 consists of "best effort" early reductions of the FIDEL data sets. We expect improvements in future data products as we have time to experiment with variant methods and techniques, and as additional data are incorporated. In this release, we have not aimed for complete consistency between the reductions for the different FIDEL survey fields, as the reductions were done at different times (as the data came in) by different subsets of the FIDEL team.

4.0 Data products

The first FIDEL data release (DR2) consists of FITS images of MIPS observations of all three FIDEL survey fields. For each field, at each wavelength where we have data, we provide three FITS images: the science image itself, an exposure map, and an estimated noise image. We describe these in more detail here.