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This paper presents new five passbands (UBVRI) optical wide-field imaging data accumulated as part of the DEEP Public Survey (DPS) carried out as a public survey by the ESO Imaging Survey (EIS) project. Out of the 3 square degrees originally proposed, the survey covers 2.75 square degrees, in at least one band (normally R), and 1.00 square degrees in five passbands. The median seeing, as measured in the final stacked images, is 0.97", ranging from 0.75" to 2.0". The median limiting magnitudes (AB system, 2" aperture, 5 sigma detection limit) are U_(AB)=25.65, B_(AB)=25.54, V_(AB)=25.18, R_(AB) = 24.8 and I_(AB)=24.12 mag, consistent with those proposed in the original survey design. The paper describes the observations and data reduction using the EIS Data Reduction System and its associated EIS/MVM library. The quality of the individual images were inspected, bad images discarded and the remaining used to produce final image stacks in each passband, from which sources have been extracted. Finally, the scientific quality of these final images and associated catalogs was assessed qualitatively by visual inspection and quantitatively by comparison of statistical measures derived from these data with those of other authors as well as model predictions, and from direct comparison with the results obtained from the reduction of the same dataset using an independent (hands-on) software system. Finally to illustrate one application of this survey, the results of a preliminary effort to identify sub-mJy radio sources are reported. To the limiting magnitude reached in the R and I passbands the success rate ranges from 66 to 81% (depending on the fields). These data are publicly available at CDS., Comment: 24 pages, 26 figures. Accepted for pubblication in A&A

This paper presents new J and Ks data obtained from observations conducted at the ESO 3.5m New Technology Telescope using the SOFI camera. These data were taken as part of the ESO Imaging Survey Deep Public Survey (DPS) and significantly extend the earlier optical/infrared EIS-DEEP survey presented in a previous paper. The DPS-IR survey comprises two observing strategies: shallow Ks observations providing nearly full coverage of pointings with complementary multi-band optical data and deeper J and Ks observations of the central parts of these fields. The DPS-IR survey provides a coverage of roughly 2.1 square degrees in Ks with 0.63 square degrees to fainter magnitudes and also covered in J, over three independent regions of the sky. The goal of the present paper is to describe the observations, the data reduction procedures, and to present the final survey products. The astrometric solution with an estimated accuracy of <0.15" is based on the USNO catalog. The final stacked images presented here number 89 and 272, in J and Ks, respectively, the latter reflecting the larger surveyed area. The J and Ks images were taken with a median seeing of 0.77" and 0.8". The images reach a median 5sigma limiting magnitude of J_AB~23.06 in an aperture of 2", while the corresponding limiting magnitude in Ks_AB is ~21.41 and ~22.16 mag for the shallow and deep strategies. Overall, the observed limiting magnitudes are consistent with those originally proposed. The quality of the data has been assessed by comparing the measured magnitude of sources at the bright end directly with those reported by the 2MASS survey and at the faint end by comparing the counts of galaxies and stars with those of other surveys to comparable depth and to model predictions. The final science-grade catalogs and images are available at CDS., Comment: Accepted for publication in A&A, 14 pages, 8 figures, a full resolution version of the paper is available from http://www.astro.ku.dk/~lisbeth/eisdata/papers/5019.pdf

This paper presents infrared data obtained from observations carried out at the ESO 3.5m New Technology Telescope (NTT) of the Hubble Deep Field South (HDF-S) and the Chandra Deep Field South (CDF-S). These data were taken as part of the ESO Imaging Survey (EIS) program, a public survey conducted by ESO to promote follow-up observations with the VLT. In the HDF-S field the infrared observations cover an area of ~53 square arcmin, encompassing the HST WFPC2 and STIS fields, in the JHKs passbands. The seeing measured in the final stacked images ranges from 0.79" to 1.22" and the median limiting magnitudes (AB system, 2" aperture, 5sigma detection limit) are J_AB~23.0, H_AB~22.8 and K_AB~23.0 mag. Less complete data are also available in JKs for the adjacent HST NICMOS field. For CDF-S, the infrared observations cover a total area of \~100 square arcmin, reaching median limiting magnitudes (as defined above) of J_AB~23.6 and K_AB~22.7 mag. For one CDF-S field H-band data are also available. This paper describes the observations and presents the results of new reductions carried out entirely through the un-supervised, high-throughput EIS Data Reduction System and its associated EIS/MVM C++-based image processing library developed, over the past 5 years, by the EIS project and now publicly available. The paper also presents source catalogs extracted from the final co-added images which are used to evaluate the scientific quality of the survey products, and hence the performance of the software. This is done comparing the results obtained in the present work with those obtained by other authors from independent data and/or reductions carried out with different software packages and techniques. The final science-grade catalogs and co-added images are available at CDS., Comment: Accepted for publication in A&A, 13 pages, 12 figures; a full resolution version of the paper is available from http://www.astro.ku.dk/~lisbeth/eisdata/papers/4528.pdf ; related catalogs and images are available through http://www.astro.ku.dk/~lisbeth/eisdata/

(Abridged) This paper presents the data recently released for the XMM-Newton/WFI survey carried out as part of the ESO Imaging Survey (EIS) project. The aim of this survey is to provide optical imaging follow-up data in BVRI for identification of serendipitously detected X-ray sources in selected XMM-Newton fields. In this paper, fully calibrated individual and stacked images of 12 fields as well as science-grade catalogs for the 8 fields located at high-galactic latitude are presented. The data covers an area of \sim 3 square degrees for each of the four passbands. The median limiting magnitudes (AB system, 2" aperture, 5\sigma detection limit) are 25.20, 24.92, 24.66, and 24.39 mag for B-, V-, R-, and I-band, respectively. These survey products, together with their logs, are available to the community for science exploitation in conjunction with their X-ray counterparts. Preliminary results from the X-ray/optical cross-correlation analysis show that about 61% of the detected X-ray point sources in deep XMM-Newton exposures have at least one optical counterpart within 2" radius down to R \simeq 25 mag, 50% of which are so faint as to require VLT observations thereby meeting one of the top requirements of the survey, namely to produce large samples for spectroscopic follow-up with the VLT, whereas only 15% of the objects have counterparts down to the DSS limiting magnitude., Comment: 24 pages, 10 figures, accepted for publication in Astronomy and Astrophysics. Accompanying data releases available at http://archive.eso.org/archive/public_datasets.html (WFI images), http://www.eso.org/science/eis/surveys/release_65000025_XMM.html (optical catalogs), http://www.aip.de/groups/xray/XMM_EIS/ (X-ray data). Full resolution version available at http://www.astro.uni-bonn.de/~dietrich/publications/3785.ps.gz

(abridged) Stellar catalogues in five passbands (UBVRI) over an area of approximately 0.3 deg^2, comprising about 1200 objects, and in seven passbands (UBVRIJK) over approximately 0.1 deg^2, comprising about 400 objects, in the direction of the Chandra Deep Field South are presented. The 90% completeness level of the number counts is reached at approximately U = 23.8, B = 24.0, V = 23.5, R = 23.0, I = 21.0, J = 20.5, K = 19.0. A scheme is presented to select point sources from these catalogues, by combining the SExtractor parameter CLASS_STAR from all available passbands. Probable QSOs and unresolved galaxies are identified by using the previously developed \chi^2-technique (Hatziminaoglou et al 2002), that fits the overall spectral energy distributions to template spectra and determines the best fitting template. The observed number counts, colour-magnitude diagrams, colour-colour diagrams and colour distributions are presented and, to judge the quality of the data, compared to simulations based on the predictions of a Galactic Model convolved with the estimated completeness functions and the error model used to describe the photometric errors of the data. The resulting stellar catalogues and the objects identified as likely QSOs and unresolved galaxies with coordinates, observed magnitudes with errors and assigned spectral types by the $\chi^2$-technique are presented and are publicly available., Comment: Paper as it will appear in print. Complete figures and tables can be obtained from: http://www.eso.org/science/eis/eis_pub/eis_pub.html. Astronomy & Astrophysics, accepted for publication

This paper describes the methodology currently being implemented in the EIS pipeline for analysing optical/infrared multi-colour data. The aim is to identify different classes of objects as well as possible undesirable features associated with the construction of colour catalogues. The classification method used is based on the xi^2-fitting of template spectra to the observed SEDs, as measured through broad-band filters. Its main advantage is the simultaneous use of all colours, properly weighted by the photometric errors. In addition, it provides basic information on the properties of the classified objects (eg redshift, effective temperature). These characteristics make the xi^2-technique ideal for handling large multi-band datasets. The results are compared to the more traditional colour-colour selection and, whenever possible, to model predictions. In order to identify objects with odd colours, either associated with rare populations or to possible problems in the catalogue, outliers are searched for in the multi-dimensional colour space using a nearest-neighbour criterion. Outliers with large xi^2-values are individually inspected to further investigate their nature. The tools developed are used for a preliminary analysis of the multi-colour point source catalogue constructed from the optical/infrared imaging data obtained for the Chandra Deep Field South (CDF-S). These data are publicly available, representing the first installment of the ongoing EIS Deep Public Survey., Comment: 18 pages, LaTeX, 16 figures, 3 tables, accepted for publication in A&A

This paper presents the first set of fully calibrated images and associated stellar catalogs of the Pre-FLAMES survey being carried out by the ESO Imaging Survey (EIS) project. The primary goal of this survey is to provide the ESO community with data sets from which suitable target lists can be extracted for follow-up observations with the new VLT facility FLAMES. For this purpose 160 stellar fields have been selected for observations in B, V and I using the 8kx8k Wide Field Imager (WFI) at the MPG/ESO 2.2 m telescope at La Silla. These data have been used to assess the observing strategy adopted and to define suitable reduction techniques and procedures for the preparation of input catalogs for FLAMES. The images and catalogs presented here are publicly available and can be requested from the URL address ``http://www.eso.org/eis''., Comment: 18 pages, 28 figures available in gif format. The postscript version of the paper with all the figures encapsulated is available at http://www.eso.org/science/eis/eis_pub/eis_pub.html. Astronomy & Astrophysics, accepted

This paper presents multi-passband optical data obtained from observations of the Chandra Deep Field South (CDF-S), located at alpha ~ 3h 32m, delta ~ -27d 48m. The observations were conducted at the ESO/MPG 2.2m telescope at La Silla using the 8kx8k Wide-Field Imager (WFI). This data set, taken over a period of one year, represents the first field to be completed by the ongoing Deep Public Survey (DPS) being carried out by the ESO Imaging Survey (EIS) project. This paper describes the optical observations, the techniques employed for un-supervised pipeline processing and the general characteristics of the final data set. The paper includes data taken in six different filters U'UBVRI. The data cover an area of about 0.25 square degrees reaching 5 sigma limiting magnitudes of U'_AB=26.0, U_AB=25.7, B_AB=26.4$, V_AB=25.4, R_AB=25.5 and I_AB= 24.7 mag, as measured within a 2xFWHM aperture. The optical data covers the area of ~ 0.1, Comment: 13 pages, 19 postscript figures, Figure 3,4,7,10 are available in jpeg format, use aa.cls style. The full postscript of the paper is available at http://www.eso.org/science/eis/eis_pub/eis_pub.html

This paper presents new J and Ks near-infrared data obtained from observations of the Chandra Deep Field South (CDF-S) conducted at the ESO 3.5m New Technology Telescope (NTT). These data were taken as part of the ongoing Deep Public Survey (DPS) being carried out by the ESO Imaging Survey (EIS) program, extending the EIS-DEEP survey. Combined these surveys now provide a contiguous coverage over an area of 400 square arcmin in the near-infrared, nearly matching that covered by the deep X-ray observations of Chandra, four times the area of the original EIS-DEEP survey. The paper briefly describes the observations and the new techniques being employed for pipeline processing jittered infrared observations, which include unbiased de-fringing and sky-background subtraction, pixel-based astrometry and stacking and pixel registration based on a multi-resolution decomposition of the images. The astrometric solution is based on a pre-release of the GSC-II catalog and has an accuracy of < 0.15 arcsec. The final images for 12 pointings presented here reach median 5 sigma limiting magnitudes of J_AB~23.4 and K_AB~22.6 as measured within an aperture 2xFWHM. The frame to frame variation of the photometric zero-point is estimated to be <0.09 mag. The data are publicly available in the form of fully calibrated J and Ks pixel maps and source lists extracted for each pointing. These data can be requested through the URL ``http://www.eso.org/eis''., Comment: 10 pages, 8 postscript figures, Figure 1 and Figures 3 are available in jpeg format, uses updated style aa.cls for Astronomy & Astrophysics. submitted to Astronomy & Astrophysics

The ESO Imaging Survey (EIS) is an ongoing project to carry out public imaging surveys to support programs on the ESO Very Large Telescope (VLT). The first phase of the project started in July 1997 and consisted of a moderately deep, large-area survey (EIS-WIDE) and a deep optical/infrared survey (EIS-DEEP) using the ESO New Technology Telescope (NTT). EIS has recently reached another milestone with the completion of a Pilot Survey using the Wide-Field Image (WFI), an 8k by 8k mosaic CCD camera mounted on the MPG/ESO 2.2m telescope at La Silla. This paper briefly reviews the results of the original EIS and gives an update of the results obtained from the observations carried out as part of the Pilot Survey. Work in progress on the development of an advanced pipeline for handling data from large CCD mosaics and facilities to make the access to data products easier for external users are also discussed., Comment: 9 pages, 9 tables and 6 figures (some at reduced resolution) in a single PDF file. To appear in the ESO Messenger

This paper presents ground-based data obtained from deep optical and infrared observations carried out at the ESO 3.5 New Technology Telescope (NTT) of a field selected for its low HI content for deep observations with AXAF. These data were taken as part of the ESO Imaging Survey (EIS) program, a public survey conducted in preparation for the first year of operation of the VLT. Deep CCD images are available for five optical passbands, reaching 2 sigma limiting magnitudes of U_AB~27.0, B_AB~27, V_AB~26.5, R_AB~26.5 and I_AB~26. An area of ~56 square arcmin is covered by UBVR observations, and ~30 square arcmin also in I. The infrared observations cover a total area of ~83 square arcmin, reaching J_AB~24.5 and K_AB~23.5. This paper describes the observations and data reduction. It also presents images of the surveyed region and lists the optical and infrared photometric parameters of the objects detected on the co-added images of each passband, as well as multicolor optical and infrared catalogs. These catalogs together with the astrometrically and photometrically calibrated co-added images are public and can be retrieved from the URL http://www.eso.org/eis/ . This data set completes the ESO Imaging Survey program sixteen months after it began in July 1997., Comment: 10 pages, 7 figures, 5 jpg

This paper presents ground-based data obtained from deep optical and infrared observations of the HST Hubble Deep Field South (HDF-S) field carried out at the ESO 3.5 New Technology Telescope (NTT). These data were taken as part of the ESO Imaging Survey (EIS) program, a public survey coordinated by ESO and member states, in preparation for the first year of operation of the VLT. Deep CCD images are available for five optical passbands, reaching 2 sigma limiting magnitudes of U_AB~27.0, B_AB~26.5, V_AB~26, R_AB~26, I_AB~25, covering a region of ~25 square arcmin, which includes the HST WPFC2 field. The infrared observations cover a total area of ~42 square arcmin and include both the HST WFPC2 and STIS fields. The observations of the WFPC2 region were conducted in JHKs passbands, reaching J_AB~25, and H_AB and K_AB~24.0. Due to time constraints, the adjacent field, covering the STIS field, has been observed only in R, I and JHKs, while no observations were conducted covering the NIC3 field. This paper describes the observations and data reduction. It also presents images of the surveyed region and lists the optical and infrared photometric parameters of the objects detected on the co-added images of each passband, as well as multicolor optical and infrared catalogs. These catalogs together with the astrometrically and photometrically calibrated co-added images are being made public world-wide and can be retrieved from the world-wide web (http://www.eso.org/eis)., Comment: 24 pages, 17 figures (7 available in jpg format), submitted to Astronomy and Astrophysics

In this paper the list of candidate clusters identified from the I-band data of the ESO Imaging Survey (EIS) is completed using the images obtained over a total area of about 12 square degrees. Together with the data reported earlier the total I-band coverage of EIS is 17 square degrees, which has yielded a sample of 252 cluster candidates in the redshift range $0.2 \lsim z \lsim 1.3$. This is the largest optically-selected sample currently available in the Southern Hemisphere. It is also well distributed in the sky thus providing targets for a variety of VLT programs nearly year round., Comment: 5 pages, 3 figures, submitted to Astronomy & Astrophysics

This paper presents the I-band data obtained by the ESO Imaging Survey (EIS) over two patches of the sky, 6 square degrees each, centered at $\alpha \sim 5^h40^m$, $\delta \sim -24^\circ50^m$, and $\alpha \sim 9^h50^m$, $\delta \sim -21^\circ 00^m$. The data are being made public in the form of object catalogs and, photometrically and astrometrically calibrated pixel maps. These products together with other useful information can be found at "http://www.eso.org/eis". The overall quality of the data in the two fields is significantly better than the other two patches released earlier and cover a much larger contiguous area. The total number of objects in the catalogs extracted from these frames is over 700,000 down to $I\sim23$, where the galaxy catalogs are 80% complete. The star counts are consistent with model predictions computed at the position of the patches considered. The galaxy counts and the angular two-point correlation functions are also consistent with those of the other patches showing that the EIS data set is homogeneous and that the galaxy catalogs are uniform., Comment: 9 pages, 11 figures, submitted to Astronomy and Astrophysics

This paper presents 19 additional candidate clusters detected using the galaxy catalog extracted from the I-band images taken for the ESO Imaging Survey (EIS). The candidates are found over a region of 1.1 square degrees, located near the South Galactic Pole. Combined with the sample reported earlier, the number of candidates in the Southern Galactic Cap is now 54 over a total area of 3.6 square degrees. Images in V band are also available over 2.7 square degrees, and galaxy catalogs extracted from them over a uniform area of 2 square degrees have been used to further explore the reality of the I cluster candidates. Nearly all the I candidates with estimated redshifts <~ 0.5 are also identified in V. At higher redshifts, only rich candidates are detected in both bands., Comment: 5 pages, 2 figures, submitted to Astronomy and Astrophysics Letters

This paper presents multicolor data obtained for a 1.7 square degree region near the South Galactic Pole (patch B) as part of the ESO Imaging Survey (EIS). So far the observations have been conducted in B,V and I but are expected to be complemented by observations in the U band later in 1998. Object catalogs extracted from single exposure images are 80% complete down to B~24, V~23.5 and I ~22.5 and once coadded should reach about 0.5 mag deeper. The data are being made public in the form of catalogs, pixel maps, target lists and image "postage stamps" which can be retrieved from the Web. Counts of stars and galaxies and the angular two-point correlation function of galaxies are computed and compared to other available data to evaluate the depth and uniformity of the extrtacted object catalogs. In addition, color distributions of stellar objects are presented and compared to model predictions to examine the reliability of the colors. The results suggest that the overall quality of the catalogs extracted from the images is good and suitable for the science goals of the survey., Comment: 12 pages, 17 figures, submitted to Astronomy and Astrophysics

This paper presents preliminary lists of potentially interesting point-like sources extracted from multicolor data obtained for a 1.7 square degree region near the South Galactic Pole. The region has been covered by the ESO Imaging Survey (EIS) in B, V,I, and offers a unique combination of area and depth.These lists, containing a total of 330 objects nearly all brighter than I~21.5, over 1.27 square degrees (after removing some bad regions), are by-products of the process of verification and quality control of the object catalogs being produced. Among the color selected targets are candidate very low mass stars/brown dwarfs (54), white-dwarfs (32), and quasars (244). In addition, a probable fast moving asteroid was identified. The objects presented here are natural candidates for follow-up spectroscopic observations and illustrate the usefulness of the EIS data for a broad range of science and for providing possible samples for the first year of the VLT., Comment: 12 pages, 6 figures, submitted to A. and A

This paper presents the preliminary results of the ESO Imaging Survey (EIS), a public survey being carried out by ESO and member states, in preparation for the VLT first-light. The survey goals, organization, strategy and observations are discussed and an overview is given of the survey pipeline developed to handle EIS data and produce object catalogs. A report is presented on moderately deep I-band observations obtained in the first of four patches surveyed, covering a region of 3.2 square degrees centered at R.A. 22h40m and Dec. -40d. The products available to the community, including pixel maps (with astrometric and photometric calibrations) and the corresponding object catalogs, are also described. In order to evaluate the quality of the data, preliminary estimates are presented for the star and galaxy number counts, and for the angular two-point correlation function obtained from the available data. The present work is meant as a preview of the final release of the EIS data that will become available later this year., Comment: 25 pages, 30 figures, submitted to Astronomy and Astrophysics

The ESO Imaging Survey (EIS) presented in early issues of the Messenger, and with up-to-date information on the ongoing observations available on the Web (http://www.eso.org/eis), is a concerted effort by ESO and the Member State community to provide targets for the first year of operation of the VLT. It consists of two parts: a relatively wide-angle survey (EIS-WIDE) to cover four pre-selected patches of sky, 6 square degrees each, spread in right ascension to search for distant clusters and quasars and a deep, multicolor survey of four optical (SUSI-2) and two infrared (SOFI) covering the HST/Hubble Deep Field South (HDFS) and its flanking fields (EIS-DEEP). From the start, the main challenge has been to carry out a public survey in a limited amount of time requiring observations, software development and data reduction with the goal of distributing the survey data products before the call for proposal for the VLT. To cope with this one-year timetable, a novel type of collaboration between ESO and the community has been established which has allowed EIS to combine the scientific and technical expertise fo the community with in-house know-how and infrastructure. In spite of the adverse weather conditions in some of the earlier runs, EIS has already proved to be successful experiment achieving most of its scientific and technical goals, thereby laying the ground work for future imaging surveys., Comment: 11 pages Latex,mprocl.sty included, 2 Postscript figures, 4 jpg figures, to be published in the ESO Messenger