Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.stecf.org/goods/spectroscopy/CDFS_Mastercat/vanzella04.ps Äàòà èçìåíåíèÿ: Thu Sep 16 11:25:46 2004 Äàòà èíäåêñèðîâàíèÿ: Tue Oct 2 01:14:35 2012 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: m 87 jet

arXiv:astro­ph/0406591
v1
25
Jun
2004
Astronomy & Astrophysics manuscript no. Vanzella August 2, 2004
(DOI: will be inserted by hand later)
The Great Observatories Origins Deep Survey
VLT/FORS2 Spectroscopy in the GOODS­South Field
E. Vanzella 1,2 , S. Cristiani 2 , M. Dickinson 3 , H. Kuntschner 4 , L. A. Moustakas 5 , M. Nonino 2 , P. Rosati 6 , D. Stern 8 ,
C. Cesarsky 6 , S. Ettori 6 , H. C. Ferguson 5 , R.A.E. Fosbury 4 , M. Giavalisco 5 , J. Haase 4 , A. Renzini 6 , A. Rettura 6,7 ,
P. Serra 4 , and the GOODS Team
1 Dipartimento di Astronomia dell'Universit‘a di Padova, Vicolo dell'Osservatorio 2, I­35122 Padova, Italy.
2 INAF ­ Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, 40131 Trieste, Italy.
3 National Optical Astronomy Obs., P.O. Box 26732, Tucson, AZ 85726.
4 ST­ECF, Karl­Schwarzschild Str. 2, 85748 Garching, Germany.
5 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218.
6 European Southern Observatory, Karl­Schwarzschild­Strasse 2, Garching, D­85748, Germany.
7 Universite' Paris­Sud 11, Rue Georges Clemenceau 15, Orsay, F­91405, France
8 Jet Propulsion Laboratory, California Institute of Technology, MS 169­506, 4800 Oak Grove Drive, Pasadena, CA 91109 #
Received ; accepted
Abstract. We present the first results of the ESO/GOODS program of spectroscopy of faint galaxies in the Chandra Deep
Field South (CDF­S). 399 spectra of 303 unique targets have been obtained in service mode with the FORS2 spectrograph at
the ESO/VLT, providing 234 redshift determinations (the median of the redshift distribution is at 1.04). The typical redshift
uncertainty is estimated to be # z # 0.001. Galaxies have been color selected in a way that the resulting redshift distribution
typically spans from z=0.5 to 2. The reduced spectra and the derived redshifts are released to the community through the ESO
web page http : //www.eso.org/science/goods/. Large scale structure is clearly detected at z # 0.67, 0.73, 1.10 and 1.61. Three
Lyman­break galaxies have also been included as targets and are confirmed to have redshifts z = 4.800, 4.882 and 5.828.
In a few cases, we observe clear [OII]3727 rotation curves, even at the relatively low resolution (# = 860) of the present
observations. Assuming that the observed velocity structure is due to dynamically­relaxed rotation, this is an indication of large
galactic masses (few times 10 11 M # ) at z # 1.
Key words. Cosmology: observations -- Cosmology: deep redshift surveys -- Cosmology: large scale structure of the universe
-- Galaxies: evolution.
1. Introduction
The Great Observatories Origins Deep Survey (GOODS) is a public, multifacility project that aims to answer some of the
most profound questions in cosmology: how did galaxies form and assemble their stellar mass? When was the morphological
di#erentiation of galaxies established and how did the Hubble Sequence form? How did AGN form and evolve, and what role do
they play in galaxy evolution? How much do galaxies and AGN contribute to the extragalactic background light? Is the expansion
of the universe dominated by a cosmological constant? A project of this scope requires large and coordinated e#orts from many
facilities, pushed to their limits, to collect a database of su#cient quality and size for the task at hand. It also requires that the
data be readily available to the worldwide community for independent analysis, verification, and follow­up.
The program targets two carefully selected fields, the Hubble Deep Field North (HDF­N) and the Chandra Deep Field South
(CDF­S), with three NASA Great Observatories (HST, Spitzer and Chandra), ESA's XMM­Newton, and a wide variety of ground­
based facilities. The area common to all the observing programs is 320 arcmin 2 , equally divided between the North and South
fields. For an overview of GOODS, see Dickinson et al. (2003), Renzini et al. (2002) and Giavalisco et al. (2004a).
Spectroscopy is essential to reach the scientific goals of GOODS. Reliable redshifts provide the time coordinate needed to
delineate the evolution of galaxy masses, morphologies, clustering, and star formation. They calibrate the photometric redshifts
Send o#print requests to: E. Vanzella (evanzell@eso.org)
# Based on observations made at the European Southern Observatory, Paranal, Chile (ESO programme 170.A­0788 The Great Observatories
Origins Deep Survey: ESO Public Observations of the SIRTF Legacy/HST Treasury/Chandra Deep Field South.)

2 E. Vanzella et al.: The Great Observatories Origins Deep Survey
that can be derived from the imaging data at 0.36­8µm. Spectroscopy will measure physical diagnostics for galaxies in the
GOODS field (e.g., emission line strengths and ratios to trace star formation, AGN activity, ionization, and chemical abundance;
absorption lines and break amplitudes that are related to the stellar population ages). Precise redshifts are also indispensable to
properly plan for future follow­up at higher dispersion, e.g., to study galaxy kinematics or detailed spectral­line properties.
The ESO/GOODS spectroscopic program is designed to observe all galaxies for which VLT optical spectroscopy is likely
to yield useful data. The program makes full use of the VLT instrument capabilities (FORS2 and VIMOS), matching targets
to instrument and disperser combinations in order to maximize the e#ectiveness of the observations. The magnitude limits and
selection bandpasses depend to some degree on the instrumental setup being used. The aim is to reach mag # 24 - 25 with
adequate S/N, with this limiting magnitude being in the B band for objects observed with the VIMOS LR­Blue grism, in the V
band for those observed in the VIMOS LR­Red grism, and in the z band for the objects observed with FORS2. This is not only a
practical limit, however, but is also well matched to the scientific aims of the GOODS program. The ACS i 775 imaging samples
rest­frame optical (B­band) light out to z = 1, where i 775 = 25 reaches 1.5 to 2 magnitudes past L # B . This is also the practical limit
for high­quality, quantitative morphological measurements from the ACS images (cf. Abraham et al. 1996). Similarly, i 775 = 25
is # 1 mag fainter than the measured L # UV for z = 3 Lyman Break Galaxies (LBGs), and 0.5 mag fainter than that at z = 4
(Steidel et al. 1999). These are the limits to which GOODS/SIRTF IRAC data will robustly measure rest­frame near­IR light, and
hence constrain the stellar mass.
In this paper we report on the first spectroscopic follow­up campaign in the Chandra Deep Field South (CDF­S), carried out
with the FORS2 instrument at the ESO VLT in the period fall 2002 ­ spring 2003 (the first 9 masks, 348 slits). Further 17 masks
have been observed during the period 2003 and early 2004, for which the reduction process has started and will be presented
elsewhere (Vanzella et al., in preparation).
The paper is organized as follows: in Sect. 2 we describe the target selection and in Sect. 3 the observations and the reduc­
tion. The redshift determination is presented in Sect. 4. In Sect. 5 we discuss the data and in Sect. 6 the conclusions are pre­
sented. Throughout this paper the magnitudes are given in the AB system (AB # 31.4 - 2.5 log# f # /nJy#), and the ACS F435W,
F606W, F775W, and F850LP filters are denoted hereafter as B 435 , V 606 , i 775 and z 850 , respectively. We assume a cosmology with
# tot
,# M
,# # = 1.0, 0.3, 0.7 and H 0 = 70 km s -1 Mpc -1 .
2. Target Selection
Objects were selected as candidates for FORS2 observations primarily based on the expectation that the detection and measure­
ment of their spectral features would benefit from the high throughput and spectral resolution of FORS2, and its reduced fringing
at red wavelengths, relative to other instrumental options such as VIMOS. In particular, we expect that the main spectral emission
and absorption features for galaxies at 0.8 < z < 1.6 would appear at very red optical wavelengths, out to # 1µm. Similarly, very
faint Lyman break galaxies at z # 4, selected as B 435 , V 606 and i 775 --dropouts from the GOODS ACS photometry, also benefit
greatly from the red throughput and higher spectral resolution of FORS2.
In practice, several categories of object selection criteria were used to ensure a su#ciently high density of target candidates
on the sky to e#ciently fill out multi­slit masks. Using ACS photometry in the AB magnitude system, these criteria were:
1. Primary catalog: (i 775 - z 850 ) > 0.6 and z 850 < 24.5. This should ensure redshifts z # 0.7 for ordinary early­type galaxies
(whose strongest features are expected to be absorption lines), and higher redshifts for intrinsically bluer galaxies likely to
have emission lines.
2. Secondary catalog: 0.45 < (i 775 - z 850 ) < 0.6 and z 850 < 24.5.
3. Photometric­redshift sample: 1 < z phot < 2 and z 850 < 24.5, using an early version of GOODS photometric redshifts like
those described by Mobasher et al. 2004.
4. i 775 ­dropout and V 606 --dropout Lyman break galaxy candidates, selected from the criteria of Dickinson et al. 2004a and
Giavalisco et al. 2004b, respectively.
5. A few miscellaneous objects, including host galaxies of supernovae detected in the GOODS ACS observing campaign.
Target selection and mask design for the 2002­3 GOODS/FORS2 campaign was carried out while the GOODS ACS obser­
vations were still in progress, and before final ACS data reduction or cataloging could be completed. The targets were therefore
selected based on interim data reductions and catalogs, initially based on only one epoch of ACS imaging, and later using the
three­epoch ACS stacks and preliminary catalogs described in Giavalisco et al. (2004a). Because of this, the actual magnitudes
and colors of the observed galaxies from the final, 5­epoch ACS image stack, which we report here in Table 2, may not exactly
match the intent of the original selection criteria. When designing the masks, we generally tried to avoid observing targets that
had already been observed in other redshift surveys of this field, namely, the K20 survey of Cimatti et al. (2002) and the survey
of X­ray sources by Szokoly et al. 2004.
In the present spectroscopic catalog there are 303 targets, 114 meeting the primary selection criterion and 56 meeting the
secondary selection criteria. The other targets belong to the remaining classes.

E. Vanzella et al.: The Great Observatories Origins Deep Survey 3
Table 1. Journal of the MXU Observations.
Mask ID UT date exp.time (s)
990247 30Dec.2002 ­ 2,6Jan. 2003 12â1200
984829 9Dec.2002 ­ 3,4Jan. 2003 12â1200
985831 5Jan. ­ 4,7Feb. 2003 15â1200 + 663
973934 7, 30, 31Jan. 2003 12â1200
952426 6,7Jan. 2003 12â1200
981451 31Jan. ­ 24,27Feb. ­ 22Nov. ­ 17Dec. ­ 30Jul. ­ 1Aug. 2003 24â1200
995131 5­6 Oct. 2002 8â1800
994852 4 Oct. 2002 8â1800
990652 8Dec. 12Nov. 2002 14â1200 + 300 + 900
3. Observations and Data Reduction
The VLT/FORS2 spectroscopic observations were carried out in service mode during several nights in 2002 and 2003. A summary
is presented in Table 1. In all cases the 300I grism was used as dispersing element without order­separating filter. This grism
provides a scale of roughly 3.2å/pixel. The nominal resolution of the configuration was # = #/##=860, which corresponds to
about 9å at 8000å. The spatial scale of FORS2 was 0.126 ## /pixel, the slit width was always 1 ## . Dithering of the targets along
the slits was applied in order to e#ectively improve the sky subtraction an the removal of CCD cosmetic defects. The mean shift
applied was ±8 pixels.
3.1. Data Reduction
Data were reduced with a semi­automatic pipeline that we have developed on the basis of the MIDAS package (Warmels 1991,
using commands of the LONG and MOS contexts (Fig. 1). The frames have been bias­subtracted and flat­fielded. For each slit the
sky background was estimated with a second order polynomial fitting. In some cases, better results have been obtained adopting
a first order polynomial. The fit has been computed independently in each column inside two windows, above and below the
position of the object (if more objects are present in the slit, a suitable modification of the windows is applied).
The resulting dithered, sky­subtracted, two­dimensional frames for each object are then averaged, with the weighting deter­
mined based on exposure time, seeing, and meteorlogical conditions. Spatial median filtering has been applied to each dithered
exposures to clean the cosmic rays. The FORS2 instrument shows an exquisite response in the red domain (beyond 8000å), in
practice no appreciable residual fringe pattern a#ects the extracted signal. Rather, the sky residuals dominate the noise in the
regions where the intensity and the density of the skylines increase (see Figure 1). The individual dithered sky­subtracted spectra
have been visually inspected to verify that the object is indeed in the expected region of the slit. This step is necessary since the
applied small spatial o#sets between the science exposures can result in objects falling too close to the slit edge or even outside
the slit (in exceptional cases). After this visual screening, the spatial o#set between di#erent exposures of the same object was
calculated on the basis of the world coordinate system (WCS) information stored in the frame headers. The individual exposures
were co­added (including the rejection of bad pixels or cosmic ray hits) after applying these spatial shifts. The frames were
shifted in the spatial direction and only by integer numbers of pixels. As the objects were su#ciently well sampled (the pixel
scale was significantly smaller than the seeing), no significant blurring of the spectra was observed, while the statistical properties
of the individual pixels were preserved.
The position of the target on the detector was estimated by collapsing 700 columns in the dispersion direction and measuring
the center of the resulting profile. The 1­D object signal was obtained using the `optimal extraction' method of MIDAS. This
procedure calculates a weighted average in each column, based on both the estimated object profile and photon statistics.
Wavelength calibration was calculated on (daytime) arc calibration frames, using three arc lamps (a He, and two Ar lamps)
providing sharp emission lines over the whole spectral range used (6000--10800å). The object spectra were then rebinned to
a linear wavelength scale. We have verified the accuracy of the wavelength calibration by checking the position of 25 narrow
skylines in the science exposures (from 5577 to 10400 å). Systematic translations of the wavelength scale have been typically
measured to be of the order of ±1å and corrected. The final (absolute) mean wavelength accuracy for all spectra is 0.9±0.1å
RMS.
Relative flux calibration was achieved by observations of standard stars listed by Bohlin et al. 1995. Since the standard stars
are typically quite blue and second order light can be substantial, the calibration spectra were obtained both with and without
order­sorting filters, providing calibration across the entire optical window. As noted previously, we opted to obtain the science
target without an order­sorting filter, implying deleterious e#ects to the flux calibration, particularly for bluer objects and at longer
wavelengths. For the red objects which dominated the FORS2 target selection, we felt that the improved wavelength coverage

4 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Fig. 1. Typical FORS2 data products for an individual slit of multi­object mask. From the top of the figure: the 2­D spectrum of
the arc lines used for the wavelength calibration, a 2­D science exposure (1200 seconds), the final flat­fielded and sky­subtracted
2­D spectrum (co­addition of 12 exposures for a total of 4 h), and at the bottom the 1­D spectrum with the identification of the
main absorption and emission lines (in this example an elliptical galaxy at z=1.100, GDS J033217.46­275234.8).
more than compensated for the slightly comprimised flux calibration. Due to both this second order light and uncertain slit losses,
we caution against using the calibrated fluxes for scientific purposes.
4. Redshift Determination
Spectra of 399 objects have been extracted. From them we have been able to determine 234 redshifts. In the large majority of
the cases the redshift has been determined through the identification of prominent features of galaxy spectra: the 4000å break,
Ca H and K, g­band, MgII 2798, AlII 3584 in absorption and Ly # , [O ##]3727, [O ###]5007, H#, H# in emission. The redshift
estimation has been performed cross­correlating the observed spectrum with templates of di#erent spectral types (S0, Sa, Sb,
Sc, Ell., Lyman Break, etc.), using the rvsao package in the IRAF environment. The redshift identifications are summarized in
Table 2 and are available at the URL http : //www.eso.org/science/goods/.
In Table 2, the column ID contains the target identifier, that is constructed out of the target position (e.g., GDS J033206.44­
274728.8) where GDS stands for GOODS South. The quality flag, indicates the reliability of the redshift determination. Quality
``A'' indicates a solid redshift determination, ``B'' a likely redshift determination, ``C'' a tentative redshift determination and ``X''
an inconclusive spectrum or three cases in which no extraction was possible. 150 objects have been classified with quality ``A'',
57 with quality ``B'', 27 with quality ``C'', 69 with inconclusive redshift determination ``X''.
The class flag groups the objects for which emission line(s) (em.), absorption­line(s) (abs.) or both (comp.) are detected
in the spectrum. The classification has been guided by the observed continuum level and slope blueward and redward of the
emission/absorption feature, by the broad­band colors and the morphology of the targets (see Figure 2). 11 objects have been
classified as stars.

E. Vanzella et al.: The Great Observatories Origins Deep Survey 5
Fig. 2. Three examples of objects classified as ``em.'' (emission­lines detected), ``abs.'' (absorption lines) and ``comp.'' (both emis­
sion and absorption lines detected).
In 38% of the cases the redshift is based only on one emission line, usually identified with [O ##]3727 or Ly # . In these cases the
continuum shape, the presence of breaks, the absence of other spectral features in the observed spectral range and the broad band
photometry are particularly important in the evaluation. In general these solo­emission line redshifts are classified as ``likely'' (B)
or ``tentative'' (C).
Finally, the comments column contains additional information relevant to the particular observation. The most common ones
summarize the identification of the principal lines, the inclination of an emission line due to internal kinematics, the weakness of
the signal (``faint''), the low S/N of the extracted spectrum (``noisy''), the 20% light radius (``Flux­radius'') for objects classified
as stars, etc.
There are two objects that are not present in the v1.0 catalog, with z = 0.957 and z = 4.882 (marked with a cross in the
Table 2). These two objects were not successfully deblended in the detection process from the brighter nearby galaxies.
The internal redshift accuracy can be estimated from a sample of 42 galaxies which have been observed twice (or more)
in independent FORS2 mask sets. The distribution of measured redshift di#erences is presented in Figure 4. The mean of the
distribution is close to zero (10 -6 ) and the redshift dispersion # z = 0.00078 and mean absolute deviation < |#z| >= 0.00055,
fairly constant with redshift. These values can be considered as a lower limit to the redshift uncertainty.
5. Discussion
5.1. Reliability of the redshift ­ comparison with VVDS
A practical way to assess the reliability of the redshifts reported in Table 2 is to compare the present results with independent
measurements of other surveys. From this point of view the recent release of the data of the VIMOS­VLT Deep Survey (VVDS,
Le Fevre et al. 2004) is particularly important. There are 39 VVDS objects in common with the first release of the FORS2
GOODS survey and Figure 5 shows the comparison of the redshift determinations. The reliability level of the redshift measure­

6 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Table 2. Spectroscopic redshift catalog.
ID(V1) z 850 (i 775 - z 850 ) zspec class. Quality comments
GDS J033206.44­274728.8 21.07 0.70 1.022 comp. A [OII], CaHK, MgI
GDS J033210.73­274819.4 24.33 0.96 1.396 em. C faint, [OII]
GDS J033210.79­274719.8 25.64 0.06 ­ ­ X faint(line@8069A?)
GDS J033210.92­274722.8 19.98 0.29 0.417 em. B CaH, g­band, [OIII], Na, H#
GDS J033210.93­274721.5 22.19 1.00 1.222 abs. A CaHK, MgI, H#
GDS J033212.00­275104.2 23.00 0.85 1.018 comp. A [OII], CaHK, g­band
GDS J033212.47­274621.4 24.06 1.03 ­ ­ X faint
GDS J033212.61­274605.1 24.05 0.53 1.378 em. A [OII], MgI
GDS J033212.79­274823.1 23.03 0.45 1.316 em. A [OII], MgII, (CaHK faint)
GDS J033213.53­274917.0 23.92 0.45 ­ ­ X faint
GDS J033214.05­275124.5 22.69 0.74 1.220 em. A [OII], MgII
GDS J033214.33­274825.2 24.91 ­0.012 ­ ­ X featureless continuum
GDS J033214.38­274825.9 27.14 0.24 ­ ­ X faint
GDS J033214.69­275258.2 23.82 0.24 1.101 em. A [OII]
GDS J033214.71­275257.2 24.27 0.48 1.360 em. B [OII]?
GDS J033214.81­274600.0 24.24 0.54 1.370 em. C [OII]?
GDS J033214.93­274659.8 23.75 0.12 ­ ­ X abs@7080A
GDS J033215.01­274633.4 23.68 0.45 1.000 abs. C D4000 break?
GDS J033215.09­275130.7 24.31 0.32 1.229 em. A [OII]
GDS J033215.88­274723.1 21.75 0.28 0.896 em. A [OII], H#, TILT
GDS J033216.02­274750.0 22.83 0.96 1.298 comp. B CaHK, [OII](line6255?)
GDS J033216.17­275241.4 22.55 0.78 1.094 abs. B CaHK, g­band, MgI­noisy
GDS J033216.28­274955.5 23.72 0.41 ­ ­ X featureless continuum
GDS J033216.34­275013.4 23.25 0.52 1.046 comp. A [OII](Sky­ABS), CaHK
GDS J033216.37­275201.3 23.28 0.11 ­ ­ X bright, abs@6271,6982,7100
GDS J033216.69­275239.0 22.57 0.88 1.045 abs. A CaHK, g­band
GDS J033216.91­274808.3 25.37 0.37 ­ ­ X faint
GDS J033216.95­274519.3 23.61 0.78 1.303 em. A [OII]
GDS J033216.98­275102.4 23.54 0.40 0.991 em. A [OII], [OIII], H#
GDS J033217.29­274807.5 21.97 0.45 0.735 abs. A CaHK
GDS J033217.29­275113.2 22.73 0.85 ­ ­ X bad­row, featureless?
GDS J033217.31­275025.0 23.50 0.19 1.612 em. A [OII]
GDS J033217.34­274844.3 24.88 0.35 1.107 em. C [OII], faint
GDS J033217.46­275234.8 21.93 0.96 1.100 abs. A CaHK, MgI
GDS J033217.47­274838.4 22.20 0.18 0.737 em. A [OII], [OIII], H#
GDS J033217.48­275248.0 21.82 1.08 1.095 abs. A CaHK, g­band
GDS J033217.56­274709.2 24.01 0.43 ­ ­ X faint
GDS J033217.56­274810.1 24.36 0.13 0.542 em. C [OII]?­faint
GDS J033217.62­275228.5 21.18 0.78 1.098 comp. A CaHK, MgI, g­band, AlII, [OII]
GDS J033217.63­274811.8 22.57 0.52 0.735 em. A [OII], CaHK, [OIII]
GDS J033217.77­274603.0 24.23 0.91 ­ ­ X faint
GDS J033217.78­274823.8 22.57 0.08 0.117 em. B H#,[OIII]
GDS J033217.80­275256.9 24.30 0.50 1.044 em. B [OII]?(SKY.ABS)
GDS J033217.91­274122.7 22.10 0.96 1.041 abs. A CaHK, MgI
GDS J033217.94­274721.5 20.04 0.53 0.732 abs. A CaHK, g­band, MgI, H#, H#, AlII
GDS J033218.01­274718.5 19.41 0.61 0.735 comp. A [OII], CaHK(noisy)
GDS J033218.03­274850.3 23.20 0.18 0.297 em. A [OIII], H#, H#
GDS J033218.07­274845.7 23.19 0.75 0.000 star B star Flux­radius = 1.261
GDS J033218.19­274746.6 23.74 1.49 0.000 star B star Flux­radius = 1.256
GDS J033218.24­274744.0 23.63 0.39 ­ ­ X featureless continuum
GDS J033218.58­274619.0 23.71 0.56 1.435 em. A [OII]
GDS J033218.61­274705.1 23.16 0.41 1.380 em. A [OII], MgII
GDS J033218.67­274915.7 24.18 0.28 ­ ­ X faint,line@8200A?
GDS J033218.70­274919.8 22.69 0.77 1.038 comp. A [OII], CaHK
GDS J033218.78­274951.3 23.82 0.44 1.294 em. A [OII], noisy
GDS J033218.79­274820.8 23.41 0.30 0.999 em. B [OII]
GDS J033218.81­274908.5 23.90 0.43 1.128 em. B [OII]?
GDS J033218.81­274910.0 23.20 0.34 0.735 comp. A [OII], CaHK
GDS J033219.15­274040.2 21.11 1.14 1.128 abs. A CaHK, MgI, g­band, bright
GDS J033219.23­274545.5 23.44 1.35 0.000 star C star? Flux­radius = 1.239
GDS J033219.30­275219.3 22.00 1.14 1.096 abs. A CaHK, MgI, g­band

E. Vanzella et al.: The Great Observatories Origins Deep Survey 7
Table 2. Spectroscopic redshift catalog.
ID(V1) z 850 (i 775 - z 850 ) zspec class. Quality comments
GDS J033219.43­274928.2 23.90 0.58 1.048 em. B [OII](SKY.ABS)
GDS J033219.48­274216.8 20.29 0.31 0.382 comp. A CaHK, low­z
GDS J033219.61­274831.0 21.87 0.10 0.671 em. A [OII], [OIII], H#
GDS J033219.68­275023.6 20.50 0.25 0.559 comp. A [OII], CaHK, [OIII], H#
GDS J033219.77­274204.0 23.34 0.86 1.044 comp. A [OII], CaHK
GDS J033219.79­274609.9 24.11 0.88 1.221 em. A [OII], MgI
GDS J033219.79­274839.3 23.55 0.52 1.357 em. A [OII]
GDS J033219.89­274517.8 24.00 0.15 ­ ­ X bright, abs@8176,6716å
GDS J033219.96­274449.8 22.35 0.24 0.783 em. C [OII]?
GDS J033219.97­274547.6 23.94 0.47 1.219 em. A [OII]
GDS J033219.99­274443.2 24.43 0.23 ­ ­ X faint
GDS J033220.02­274104.2 21.51 0.52 0.682 abs. A CaHK, g­band, MgI
GDS J033220.11­275329.8 24.44 0.75 1.385 em. C [OII]?
GDS J033220.28­275233.0 22.22 0.92 1.119 abs. A CaHK, MgI, g­band
GDS J033220.29­274718.2 23.94 0.32 ­ ­ X faint, noisy
GDS J033220.41­274641.7 24.15 0.35 1.227 em. A [OII]
GDS J033220.72­274932.6 24.16 0.80 ­ ­ X faint
GDS J033220.91­275344.0 22.99 0.71 1.044 em. B [OII](SKY.ABS), CaHK
GDS J033221.22­274625.9 23.48 0.50 1.221 em. A [OII]
GDS J033221.57­274941.6 23.01 0.61 1.110 em. A [OII]
GDS J033221.63­274800.2 24.35 0.08 ­ ­ X featureless continuum
GDS J033221.67­274056.0 22.75 0.65 1.045 em. B [OII](SKY.ABS), CaHK
GDS J033221.76­274442.1 20.86 0.18 0.295 em. A H#, [OIII], H#
GDS J033221.81­274352.3 24.27 0.58 1.308 em. B [OII]
GDS J033221.84­274434.4 24.81 0.36 ­ ­ X faint
GDS J033221.99­274655.9 20.42 0.47 0.670 comp. A [OII], CaHK, g­band
GDS J033222.18­274659.7 25.00 1.04 ­ ­ X faint
GDS J033222.36­275018.4 22.82 0.27 0.736 em. B [OII]
GDS J033222.41­274858.0 24.19 0.46 1.383 em. A [OII], MgI, MgII
GDS J033222.47­275047.4 24.38 1.79 0.000 star C star? Flux­radius = 1.307
GDS J033222.54­274603.8 24.32 0.25 ­ ­ X faint(line@9400å?)
GDS J033222.58­274425.8 20.28 0.33 0.738 comp. A [OII], H#, CaHK,MgI
GDS J033222.93­274919.1 24.77 0.51 1.298 em. B [OII]?
GDS J033222.93­275104.6 22.89 0.38 0.905 em. A [OII], H#
GDS J033223.17­274219.6 23.82 0.78 ­ ­ X faint(abs@8157,9200)
GDS J033223.18­274921.5 24.08 0.55 1.109 em. B [OII]
GDS J033223.26­275101.8 21.90 0.85 0.964 abs. A CaHK, g­band
GDS J033223.28­274744.7 23.94 0.24 0.764 em. B [OII]
GDS J033223.29­274742.6 24.31 0.41 1.092 em. A [OII], CaK
GDS J033223.40­274316.6 20.48 0.33 0.615 comp. A [OII], CaHK, g­band, H#, [OIII]
GDS J033223.45­274709.0 23.22 0.49 1.423 em. A [OII], MgII
GDS J033223.61­274601.0 22.57 1.06 1.033 em. A [OII], red
GDS J033223.61­275306.3 22.30 0.85 1.125 abs. C CaHK? (noisy)
GDS J033223.69­275324.4 20.41 0.40 0.532 comp. A [OIII], H#
GDS J033223.83­274639.4 24.19 0.84 1.222 em. B [OII]
GDS J033223.90­275326.2 23.81 1.07 ­ ­ X faint
GDS J033224.01­275039.0 22.74 0.98 1.094 abs. A CaHK,MgI
GDS J033224.08­275214.6 23.56 0.92 1.015 em. C [OII]?, g­band?
GDS J033224.11­274102.1 23.36 0.88 0.000 star A star Flux­radius = 1.247
GDS J033224.20­274257.5 24.15 0.32 ­ ­ X featureless continuum
GDS J033224.20­274952.9 23.61 0.21 ­ ­ X di#use, faint
GDS J033224.26­274126.4 20.18 0.44 0.533 comp. A [OII], [OIII], H#, g­band
GDS J033224.37­274315.2 24.63 ­0.06 1.271 em. C [OII]?
GDS J033224.39­274624.3 21.92 0.76 0.895 abs. A CaHK, [OII] faint, (short­slit)
GDS J033224.66­275051.9 22.40 ­0.28 0.272 em. C H#, Mg?
GDS J033224.72­274120.4 21.17 0.80 0.967 abs. A CaHK, g­band, MgI, AlII
GDS J033224.79­274912.9 24.90 1.61 0.000 star C continuum+break, Flux­radius = 1.284
GDS J033224.85­275052.6 23.24 0.61 1.329 em. A [OII]
GDS J033224.90­274715.0 24.65 0.71 ­ ­ X faint
GDS J033224.91­274923.7 23.87 0.08 ­ ­ X featureless bright continuum

8 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Table 2. Spectroscopic redshift catalog.
ID(V1) z 850 (i 775 - z 850 ) zspec class. Quality comments
GDS J033225.04­274718.2 23.86 0.51 1.357 em. A [OII], MgII
GDS J033225.10­274219.5 23.65 1.09 1.609 em. B [OII]
GDS J033225.19­274735.3 23.90 0.60 1.017 em. B [OII], faint
GDS J033225.20­275009.4 22.88 0.95 1.100 abs. B CaHK, AlII
GDS J033225.21­275335.0 21.17 0.72 0.833 comp. A [OII], [OIII], CaHK, H#, (noisy)
GDS J033225.35­274502.8 22.58 0.16 0.975 em. A [OII], H#, [OIII]
GDS J033225.47­274327.6 20.14 0.51 0.668 abs. A CaHK, [OII], AlII
GDS J033225.48­275211.6 23.68 0.39 1.312 em. B [OII]
GDS J033225.54­275209.1 22.93 0.45 0.955 em. B [OII]?, noisy
GDS J033225.55­275108.2 23.93 0.30 0.832 em. A [OII], [OIII], H#
GDS J033225.58­274529.0 24.33 0.15 0.667 em. A [OII], [OIII]
GDS J033225.69­274347.1 24.73 1.01 ­ ­ X faint
GDS J033225.76­274347.0 23.02 1.11 ­ ­ X noisy, bad­row
GDS J033225.77­274247.7 24.26 0.62 1.026 em. B [OII](SKY.ABS)
GDS J033225.79­274352.3 23.17 0.58 1.297 em. A [OII], CaHK
GDS J033225.86­275019.7 21.54 0.48 1.095 em. A bright [OII], TILT
GDS J033225.90­274341.2 18.92 0.88 0.000 star C star? Flux­radius = 1.296
GDS J033226.00­274150.6 21.75 0.23 0.545 comp. A [OII], H#, CaHK
GDS J033226.03­275147.7 22.98 0.53 1.242 em. A [OII], MgI
GDS J033226.16­274946.5 23.09 0.52 0.735 comp. A [OII], CaHK
GDS J033226.17­274603.6 24.25 0.54 1.219 em. B [OII]
GDS J033226.24­275005.6 23.68 0.73 1.096 em. B [OII]
GDS J033226.26­274209.6 23.96 0.53 0.932 em. B [OII]
GDS J033226.31­274722.4 22.48 0.23 0.737 em. A [OII], H#, [OIII]
GDS J033226.32­274232.3 23.86 0.24 0.736 em. B [OII]
GDS J033226.40­274228.2 23.33 0.42 1.615 em. A [OII], MgII
GDS J033226.49­274035.5 19.60 0.19 ­ ­ X faint
GDS J033226.64­274028.2 21.22 0.21 0.310 em. A low­z, H#, [OIII]
GDS J033226.66­274025.1 21.70 0.29 1.042 em. C [OII]?(SKY.ABS)
GDS J033226.66­274029.8 22.06 0.89 1.040 abs. A CaHK, g­band, MgI
GDS J033226.67­274758.8 21.81 0.20 0.628 em. C H#, [OIII]?
GDS J033226.67­274834.8 23.59 0.55 0.905 abs. C D4000break?
GDS J033226.84­274545.3 23.47 0.52 1.306 em. A [OII]
GDS J033226.89­274541.9 23.72 0.13 0.338 em. A [OII], H#, [OIII], H#
GDS J033226.92­274239.8 22.95 0.37 ­ ­ X featureless?
GDS J033227.02­274407.2 22.15 0.84 1.128 comp. A [OII], CaHK
GDS J033227.05­275318.4 22.25 0.70 1.103 comp. A [OII], CaHK
GDS J033227.07­274404.7 22.24 0.16 0.739 em. A [OII], H#, [OIII]
GDS J033227.11­274922.0 22.88 ­0.01 0.559 em. A [OII], H#, [OIII], H#
GDS J033227.17­274957.8 23.26 0.51 1.293 em. A [OII], CaHK
GDS J033227.36­274204.8 21.26 0.53 0.735 comp. A CaHK, MgI, AlII, g­band
GDS J033227.58­274051.7 23.43 0.94 1.070 em. C faint, [OII]?
GDS J033227.70­274043.7 21.64 0.86 0.968 abs. A CaHK, g­band, AlII
GDS J033227.72­275040.8 21.42 0.74 1.097 comp. A [OII], CaHK
GDS J033227.84­274136.8 21.97 0.91 1.043 abs. A CaHK, g­band, MgI, AlII
GDS J033227.88­275140.4 20.26 0.40 0.521 abs. A CaHK, g­band
GDS J033228.09­275202.4 20.29 0.41 0.560 abs. A g­band, Na, Mg, [OIII]
GDS J033228.42­274700.2 24.31 0.19 ­ ­ X faint, abs@7060
GDS J033228.44­274703.7 20.86 0.47 ­ ­ X noisy
GDS J033228.45­274419.3 22.78 0.50 1.135 em. A [OII], MgII
GDS J033228.48­274059.6 23.82 0.49 ­ ­ X featureless continuum
GDS J033228.56­274055.7 25.44 0.07 ­ ­ X faint
GDS J033228.84­274132.7 25.43 0.01 4.800 em. C Ly # ? No continuum
GDS J033228.88­274129.3 20.72 0.53 0.733 comp. A [OII], CaHK, MgI, g­band, H#, H#
GDS J033228.94­274600.6 23.82 0.98 ­ ­ X abs@8555,8150,9200?
GDS J033228.94­274128.2+ ­ ­ 4.882 em. B Ly # , (SiIV?)
GDS J033228.99­274908.4 20.56 0.73 1.095 abs. A CaHK, MgI, g­band
GDS J033229.07­274153.1 24.27 0.44 ­ ­ X faint
GDS J033229.22­274707.6 20.65 0.51 0.668 abs. A CaHK, g­band
GDS J033229.32­274054.0 23.74 0.74 ­ ­ X short­slit
+ not present in the catalog v1.0

E. Vanzella et al.: The Great Observatories Origins Deep Survey 9
Table 2. Spectroscopic redshift catalog.
ID(V1) z 850 (i 775 - z 850 ) zspec class. Quality comments
GDS J033229.35­275048.5 20.10 0.30 0.415 abs. A H#, Mg, Na
GDS J033229.48­274036.7 24.04 0.42 1.221 em. C [OII]?
GDS J033229.63­274511.3 24.07 0.70 1.033 em. A [OII], MgI, CaH
GDS J033229.65­274524.7 24.20 0.73 ­ ­ X faint
GDS J033229.71­274507.2 22.24 0.17 0.736 em. A [OII], H#, [OIII]
GDS J033229.75­275147.1 23.25 0.54 1.315 em. A [OII]
GDS J033229.85­274520.5 21.01 0.56 0.953 em. A [OII], AlII
GDS J033229.87­274317.7 22.73 0.79 1.097 comp. B CaHK, faint [OII]
GDS J033229.99­274322.6 24.42 0.98 ­ ­ X faint
GDS J033230.03­275026.8 23.43 0.83 1.005 abs. B CaHK, MgII, g­band
GDS J033230.06­274523.5 21.81 0.50 0.955 em. A [OII]
GDS J033230.07­274319.0 21.59 0.64 1.101 comp. B [OII], CaHK
GDS J033230.09­275100.3 20.80 0.52 0.733 abs. A CaHK, g­band, MgI, AlII, H#, H#
GDS J033230.23­274519.9 23.14 0.09 0.523 em. A [OII]
GDS J033230.34­274523.6 21.92 0.07 1.223 comp. A faint [OII], CaHK, MgI
GDS J033230.51­275004.4 23.85 1.03 ­ ­ X faint
GDS J033230.70­274928.7 22.69 0.16 ­ ­ X faint
GDS J033230.71­274617.2 22.24 0.66 1.307 em. A [OII], TILT
GDS J033230.75­274306.9 23.25 0.25 0.860 em. A [OII], H#
GDS J033230.83­274931.8 23.19 0.79 ­ ­ X abs@7150,9056? (noisy)
GDS J033230.85­274621.7 21.60 0.74 1.018 comp. A CaHK, [OII]
GDS J033230.98­274434.9 23.71 0.50 1.222 em. A [OII]
GDS J033231.04­274050.2 21.74 0.77 1.037 abs. A CaHK, g­band, MgI
GDS J033231.22­274052.2 22.86 0.58 1.333 em. B [OII], noisy
GDS J033231.22­274532.7 22.98 1.00 1.097 abs. A CaHK, g­band
GDS J033231.28­274820.2 23.10 0.65 1.173 comp. A [OII]
GDS J033231.42­274324.1 23.01 0.82 1.025 em. B [OII](SKY.ABS)
GDS J033231.45­274435.0 17.90 0.49 0.000 star A star Flux­radius = 1.299
GDS J033231.55­275028.8 23.96 0.68 ­ ­ X faint red
GDS J033231.65­274504.8 23.16 0.54 1.098 em. A [OII], MgI, CaHK, H#, H#
GDS J033232.04­274451.7 21.59 0.68 0.895 abs. A CaHK
GDS J033232.08­274119.4 22.59 0.53 1.036 em. B [OII](SKY.ABS)
GDS J033232.08­274155.2 23.00 0.39 0.960 abs. C abs@7000,6400,7800
GDS J033232.12­274359.3 24.66 0.18 ­ ­ X faint (line at 6217A?)
GDS J033232.14­274349.9 23.12 0.36 0.973 em. A [OII]
GDS J033232.32­274343.6 22.80 0.07 0.533 em. C [OIII]
GDS J033232.33­274345.8 23.95 0.42 1.025 em. B [OII]
GDS J033232.58­275053.9 21.61 0.21 0.669 em. B [OII], H#
GDS J033232.73­274538.8 21.69 0.31 ­ ­ X short­slit(line5900A)
GDS J033232.73­275102.5 20.78 0.58 0.735 abs. A CaHK, g­band
GDS J033232.94­274543.9+ ­ ­ 0.957 em. A [OII]
GDS J033232.96­274545.7 19.84 0.33 0.366 abs. A N[II]+abs.spec.
GDS J033233.00­275030.2 20.85 0.44 0.669 em. A [OII], [OIII], H#
GDS J033233.01­274829.4 22.80 0.12 0.664 em. A [OIII], H#
GDS J033233.02­274547.4 21.13 0.63 0.953 abs. B CaHK, [OII]
GDS J033233.08­275123.9 21.39 0.47 0.735 abs. A CaHK
GDS J033233.25­274117.4 24.06 0.86 ­ ­ X continuum, faint
GDS J033233.28­274236.0 24.55 1.09 1.215 em. B [OII], faint red (XCDFS265)
GDS J033233.41­274230.5 23.37 0.06 0.975 em. B [OII]
GDS J033233.71­274210.2 23.71 0.46 1.043 em. B [OII](SKY.ABS), TILT
GDS J033233.82­274410.0 21.11 0.42 0.667 abs. A CaHK, g­band
GDS J033233.85­274600.2 23.82 1.05 1.910 abs. B MgII
GDS J033234.00­274412.1 23.70 0.53 0.896 em. B [OII], CaHK?
GDS J033234.05­274937.8 22.91 0.71 0.832 comp. A [OII], CaHK
GDS J033234.08­274222.3 23.91 0.72 1.476 em. B [OII]
GDS J033234.82­274835.5 22.94 0.66 1.245 em. A [OII], CaHK
GDS J033234.85­274640.4 22.70 0.61 1.099 em. A [OII]
GDS J033235.08­274615.7 23.11 0.63 1.316 em. A [OII]
GDS J033235.11­275009.0 24.17 0.44 1.295 em. A [OII]
+ not present in the catalog v1.0

10 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Table 2. Spectroscopic redshift catalog.
ID(V1) z 850 (i 775 - z 850 ) zspec class. Quality comments
GDS J033235.19­275103.4 24.41 0.23 0.981 em. B [OII]?
GDS J033235.26­275104.8 22.79 0.44 0.734 abs. A CaHK, H#, MgI
GDS J033235.78­274627.5 22.76 0.89 1.094 comp. A [OII], CaHK
GDS J033235.79­274734.7 23.65 0.88 1.223 em. A [OII], [NeIII]
GDS J033236.04­275004.3 23.40 0.81 1.612 em. A [OII], MgII
GDS J033236.39­274747.0 23.18 0.17 ­ ­ X abs@6500,6586
GDS J033236.43­274750.6 22.41 0.13 0.127 em. B H#, [OI]6300å, Na
GDS J033237.19­274608.1 20.90 1.07 1.096 abs. A CaHK
GDS J033237.26­274610.3 22.17 0.19 0.736 comp. A [OII], CaHK
GDS J033237.56­274646.7 24.89 0.78 ­ ­ X abs@8195, em@8949?
GDS J033238.27­274604.0 24.46 1.07 ­ ­ X faint
GDS J033238.49­274702.4 21.26 0.76 0.953 abs. A CaHK, MgI
GDS J033239.01­274722.7 24.40 0.40 ­ ­ X faint
GDS J033239.35­275016.3 22.05 0.42 ­ ­ X smoothly­red
GDS J033239.56­274851.7 22.55 0.81 0.000 star C star Flux­radius = 1.269
GDS J033239.60­274909.6 20.72 0.89 0.980 abs. A CaHK, g­band, AlII
GDS J033239.64­274709.1 22.70 0.99 1.317 comp. A [OII], CaHK, MgI
GDS J033239.67­274850.6 24.55 0.21 ­ ­ X featureless continuum
GDS J033239.99­275114.2 23.75 0.62 ­ ­ X lines:8210,8800?
GDS J033240.01­274815.0 25.33 1.44 5.828 em. A Ly #
GDS J033240.67­275032.3 24.56 0.21 ­ ­ X bad­row, faint
GDS J033240.79­275035.1 21.69 0.12 0.213 em. A H#, S[II], (2d­order­light)
GDS J033240.92­274823.8 24.00 0.45 1.244 em. B [OII]?
GDS J033241.21­274932.4 24.26 0.94 ­ ­ X faint
GDS J033241.41­274457.5 23.02 0.80 ­ em. X em.lines@6815,8208
GDS J033241.48­274440.4 23.00 0.84 1.296 em. B [OII], faint
GDS J033241.59­275003.0 22.32 0.66 0.000 star B compact, Flux­radius = 1.279
GDS J033241.67­274448.7 23.83 0.14 ­ ­ X faint, short­slit
GDS J033241.76­274619.4 20.93 0.35 0.333 em. C low­z, H#
GDS J033242.07­274911.6 23.42 1.30 0.000 star B star Flux­radius = 1.253
GDS J033242.21­274953.9 23.83 0.37 1.377 em. A [OII], MgI
GDS J033242.25­274625.4 22.50 0.63 1.288 em. A [OII], MgII
GDS J033242.32­274950.3 20.33 0.29 ­ ­ X noisy
GDS J033242.38­274707.6 23.18 1.11 1.314 abs. B [OII], CaHK
GDS J033242.56­274550.2 22.21 0.16 0.218 em. A [OIII], H#, H#
GDS J033242.97­274649.9 23.44 0.89 ­ ­ X faint
GDS J033244.18­274729.4 23.55 0.44 1.220 em. A [OII]
GDS J033244.20­274733.5 21.53 0.20 0.737 em. A [OII], [OIII], H#
GDS J033244.23­275039.5 24.72 0.40 1.122 em. B [OII]?
GDS J033244.29­275009.7 22.62 0.86 1.038 abs. A CaHK, g­band
GDS J033244.43­274641.8 22.55 0.13 0.215 em. C H#?
GDS J033244.62­274632.2 23.20 0.44 1.426 em. A [OII], MgII
GDS J033244.80­274920.6 23.69 0.84 ­ ­ X faint
GDS J033245.15­274940.0 21.92 1.04 1.123 abs. A CaHK, g­band, MgI
GDS J033245.21­274858.0 24.65 0.51 1.463 em. A [OII]
GDS J033245.90­274517.2 23.79 0.39 1.036 em. A [OII], CaHK
GDS J033247.45­274603.9 23.98 0.51 ­ ­ X faint
GDS J033248.56­274504.6 22.19 0.88 1.115 abs. C CaHK, noisy
GDS J033249.04­275015.5 22.36 0.80 1.122 em. B [OII]
GDS J033249.09­274519.2 21.46 0.37 ­ ­ X featureless continuum
GDS J033249.11­274524.2 21.81 0.60 1.094 em. A [OII], H#­faint
GDS J033249.49­274534.2 23.94 0.17 1.609 em. A [OII]
GDS J033249.85­274757.8 22.78 0.67 1.146 em. B [OII]?
GDS J033250.69­274732.2 23.51 ­0.02 ­ ­ X em@7100A, abs8100A
GDS J033251.34­274742.7 24.09 0.76 1.298 em. B [OII], noisy
GDS J033251.57­275044.7 22.48 0.52 0.980 comp. A [OII], H#
GDS J033252.87­275114.7 21.20 0.63 1.002 comp. A CaHK, [OII]
GDS J033252.88­275119.8 21.84 0.47 1.220 em. A [OII], CaHK
GDS J033253.01­275000.5 24.05 0.09 ­ ­ X faint
GDS J033253.34­275104.6 25.50 ­0.08 0.912 em. C noisy, [OII]?
GDS J033255.00­275051.6 21.70 0.37 ­ ­ X featureless continuum

E. Vanzella et al.: The Great Observatories Origins Deep Survey 11
Fig. 3. Color­magnitude diagram for the spectroscopic sample as a function of the quality flag. The uncertainties in the redshift
determination increase with increasing z 850 magnitude. Few bright sources (often serendipitous; z 850 < 22) have inconclusive
redshift determinations due to the dithering procedure, which has positioned these sources o# the slitlets for many of the expo­
sures.
ments in the VVDS is indicated by a quality flag. Flags 2, 3, 4 are the most secure with a confidence of 75%, 95% and 100%
respectively. Flag 1 is an indicative measurement, flag 9 indicates that there is only one secure emission line, and flag 0 indicates
a measurement failure with no features identified.
For 29 cases out of 39 (74%) the agreement is very good, with a mean di#erence < z FORS2 - z VVDS > = 0.0016 ± 0.0021.
Assuming equipartition of the redshift uncertainties between FORS2 and VVDS, we can estimate a # z (FORS 2) # 0.0015,
in reasonable agreement with the estimate of Sect. 4. In the following we will assume a typical uncertainty of the redshift
determinations of the present survey to be # z # 0.001 (excluding ``catastrophic'' discrepancies).
Ten cases show ``catastrophic'' discrepancies, i.e. < z FORS2 - z VVDS > greater than 0.015 and are reported in Table 3.
In the following we discuss case by case the origin of the discrepancy:

12 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Fig. 4. Redshift di#erences between objects observed twice or more in independent FORS2 observations. The distribution has a
dispersion # z = 0.00078.
1. GDS J033214.05­275124.5:
-- FORS2: the emission line [O ##]3727 and the absorption lines Ca H and K are detected in the FORS2 spectrum at z=1.220.
The absorption line MgII 2798 is also present at 6210å. The 4000å Balmer Break is also evident, quality flag ``A''.
-- VVDS: the main emission feature in the VIMOS spectrum is identified with [O ##]3727 at z=1.325, quality flag 3. We
note an absorption feature in the VIMOS spectrum (without identification) at #6200å, consistent with the one measured
in the FORS2 spectrum.
2. GDS J033219.79­274839.3:
-- FORS2: flat continuum with an evident emission line at #8784å. We interpret it as [O ##]3727. No spectroscopic feature
is observed at # 6500å. Quality flag A.
-- VVDS: the main feature in the VIMOS spectrum is identified with [O ###]5007 at z=0.568 (emission line at 7851å),
quality flag 2.

E. Vanzella et al.: The Great Observatories Origins Deep Survey 13
Fig. 5. VVDS spectroscopic redshift versus FORS2 spectroscopic redshift. There are 39 galaxies in common between the VVDS
sample and the sample presented in this work. 10 cases show (filled symbols) discrepant redshift determination with |dz| >0.015.
3. GDS J033221.67­274056.0:
-- FORS2: the emission line [O ##]3727 and the absorption lines Ca H and K are detected in the FORS2 spectrum at z = 1.045,
quality flag ``B''. The [O ##]3727 line is attenuated by the sky absorption band at #7600å.
-- VVDS: Ca H and K are identified in the VIMOS spectrum at z=0.977, quality flag 1.
4. GDS J033226.03­275147.7:
-- FORS2: the emission line [O ##]3727 (at 8356å) and the absorption lines Ca H and K, MgI and B2630 are detected in the
FORS2 spectrum at z = 1.242, quality flag ``A''.
-- VVDS: the main feature is identified with H# at z=0.264 (at 8296å), quality flag 9. No emission lines are present in the
FORS2 spectrum at this wavelength.
5. GDS J033231.65­274504.8:

14 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Table 3. Galaxies with discrepant redshifts between the FORS2 and VVDS surveys.
N ID z(FORS2) QF(FORS2) z(VVDS) QF(VVDS) z(FORS2)­z(VVDS)
1 GDS J033214.05­275124.5 1.220 A (em.) 1.325 3 ­0.105
2 GDS J033219.79­274839.3 1.357 A (em.) 0.568 2 0.789
3 GDS J033221.67­274056.0 1.045 B (em.) 0.978 1 0.067
4 GDS J033226.03­275147.7 1.242 A (em.) 0.264 9 0.978
5 GDS J033231.65­274504.8 1.098 A (em.) 1.443 1 ­0.350
6 GDS J033232.32­274343.6 1.059+ C (em.) 0.533 3 0.526
7 GDS J033242.38­274707.6 1.314 B (abs.) 0.688 2 0.626
8 GDS J033242.56­274550.2 0.218 A (em.) 0.635 2 ­0.417
9 GDS J033249.04­275015.5 1.122 B (em.) 1.072 2 0.05
10 GDS J033249.85­274757.8 1.146 B (em.) 1.254 2 ­0.105
+ Adopted FORS2 value has been updated to VVDS value in Table 2.
-- FORS2: the emission line [O ##]3727 and the absorption lines Ca H and K, MgI, H# and are detected in the FORS2
spectrum at z = 1.098; the emission line H# is also detected at #9105å, quality flag ``A''.
-- VVDS: in the VIMOS spectrum a line is detected at #9105å, interpreted as [O ##]3727 at z=1.443, quality flag 1.
6. GDS J033232.32­274343.6:
-- FORS2: for this object (at the border of the FORS2 field of view) the spectrum starts at #6400å. We detect a weak
emission line at #7654å (close to a sky absorption band), that we originally interpreted to be [O ##]3727 at z#1.059,
assigning to the redshift a quality flag ``C''.
-- VVDS: in the VIMOS spectrum an emission line at #5713å is detected, interpreted as [O ##]3727 at z=0.533 and quality
flag 3 (the absorption feature Ca H at #6085å is also present). It is consistent with the interpretation [O ##]3727 at
z = 0.533 with the FORS2 # 7654å emission line identified as [O ###]5007 at z = 0.533. We have therefore updated the
entry in Table 2 to a redshift z = 0.533.
7. GDS J033242.38­274707.6:
-- FORS2: this is a red object (i 775 - z 850 = 1.11), we detect two clear absorption features in the # 9100å sky free region
interpreted as Ca H and K, faint [O ##]3727 seems to be present, quality flag ``B''.
-- VVDS: red spectrum, Ca H and K are identified in the VIMOS spectrum at z=0.688, quality flag 2.
8. GDS J033242.56­274550.2:
-- FORS2: the emission lines [O ###]5007 (at 6098å), H# (at 5921 å) and H# (at 7994å) are detected in the FORS2 spectrum,
z=0.218, quality flag ``A''.
-- VVDS: the main emission feature (at 6094å) is identified with [O ##]3727 at z=0.635, quality flag 2.
9. GDS J033249.04­275015.5:
-- FORS2: the spectrum starts at #6400å. It shows continuum with a evident emission line at #7909å interpreted as
[O ##]3727 (z=1.122), a discontinuity consistent with the 4000å Balmer Break is present, quality flag ``B''.
-- VVDS: the main feature in the VIMOS spectrum is an emission line at 7723åidentified with [O ##]3727 at z=1.072,
quality flag 2.
10. GDS J033249.85­274757.8:
-- FORS2: object red with bright continuum, the emission line [O ##]3727 and the absorption lines MgII 2798 and H# are
detected in the FORS2 spectrum, the 4000å Balmer Break is also evident, quality flag ``B''.
-- VVDS: flat continuum, the NeV absorption line is identified at z=1.254, quality flag 2.
In summary, out of ten highly discrepant cases we have found only one that can be ascribed to an evident error in the
identification of the features in the FORS2 spectrum (and the original quality flag for this object was ``C''). We conclude that the
probable fraction of ``catastrophic'' misidentifications in Table 2 is at most a few percent.
5.2. Reliability of the redshifts ­ diagnostic diagrams
As mentioned above, the photometric information and its relation with the redshift provides useful indications about possible
errors in the redshift measurement and/or magnitude estimation. The Figures 6, 7 and 8 show the redshift­magnitude, the color­
redshift and the color­magnitude distributions for the spectroscopic sample (the quality flag ``A'' and ``B'' have been selected in
the Figures 7 and 8, while all sources have been plotted in the Figure 6). In figure 7 the two populations of ``emission­line'' and
``absorption­line'' (typically elliptical) galaxies are clearly separated. The mean color of the ``absorption­line'' objects increases
from i 775 - z 850 = 0.46 ± 0.079 at < z > = 0.6 to i 775 - z 850 = 0.86 ± 0.18 at < z > = 1.0, consistent but increasingly bluer than the
colors of a non­evolving L # elliptical galaxy (estimated integrating the spectral templates of Coleman, Wu & Weedman (1980)
through the ACS bandpasses).

E. Vanzella et al.: The Great Observatories Origins Deep Survey 15
Fig. 6. Spectroscopic redshift versus magnitude for the entire FORS2 sample (quality flag ``A'', ``B'', ``C'' and ``X''). Stars are
denoted by star­like symbols at zero redshift. Inconclusive spectra are placed at z = -1.
The ``emission­line'' objects show in general a bluer i 775 - z 850 color and a broader distribution than the ``absorption­line''
sources: i 775 - z 850 = 0.16 ± 0.13 at < z > = 0.6 and i 775 - z 850 = 0.52 ± 0.21 at < z > = 1.1. The broader distribution, with
some of the ''emission­line'' objects entering the color regime of the ellipticals, is possibly explained by dust obscuration, high
metallicity or strong line emission in the z 850 band.
5.3. Redshift distribution and Large Scale Structure
Figure 9 shows the redshift distribution of the objects observed in the present survey. The majority of the sources are at redshift
around #1 (the median of the redshift distribution is at 1.04), in agreement with the main criterion for the target selection (see
Sect. 2). Table 4 shows the fraction of determined redshifts as a function of the spectral features identified, i.e. emission lines,
absorption lines, emission & absorption lines, and no reliable spectral features (unclassified). There are 49 galaxies identified

16 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Fig. 7. Color­redshift diagram of the spectroscopic sample. Only redshifts with quality flag ``A'' and ``B'' have been selected.
Filled pentagons symbols are objects identified with absorption features only (``abs.'' sources), while open pentagons are objects
showing only emission lines (``em.'' sources). The intermediate cases are shown by filled triangles (``comp.'' sources). The long­
dashed line and the short dashed line show the colors of a non­evolving L # elliptical galaxy and an Scd galaxy, respectively,
estimated integrating the spectral templates of Coleman, Wu & Weedman (1980) through the ACS bandpasses.
with absorption lines only (mainly Ca H and K) in the range of redshift between 0.4­1.3; an example is shown in Figure 1. In 46%
of the total sample we have measured emission lines (mainly [O ##]3727), many of them entering the so­called ``spectroscopic
desert'' up to z=1.61.
The main peaks in the redshift distribution are at z # 0.73 (21 galaxies) and 1.1 (25 galaxies). Two concentrations at z # 1.6
(with 5 galaxies at the mean redshift < z >= 1.612 ± 0.003, see the two dimensional spectra in Figure 11) and z # 0.67 (9
galaxies) are also apparent. The presence in the CDF­S of large scale structure, (LSS) at z # 0.73 and z # 0.67 is already known
(Cimatti et al. (2002), Gilli et al. 2003, Le Fevre et al. 2004). The peak at z # 1.1 seems to be a new indication of large scale

E. Vanzella et al.: The Great Observatories Origins Deep Survey 17
Fig. 8. Color­magnitude diagram for the spectroscopic sample. Only redshifts with quality flag ``A'' and ``B'' have been selected.
The symbols are the same as in Figure 7.
structure, of the 25 galaxies in the range 1.09 galaxies.
The significance of the LSS at z = 1.61 is confirmed by:
1. the observations of Gilli et al. (2003) who found a peak in the redshift distribution of X­ray sources at z=1.618 (5 galaxies)
and measured a Poissonian probability of 3.8â10 -3 for a chance distribution ;
2. three more galaxies at z = 1.605, 1.610, 1.615 in the K20 survey Cimatti et al. (2002);
The structure at z # 1.61 is extending across a transverse size of # 5 Mpc in a wall­like pattern rather than a group structure
(see Fig. 10).

18 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Table 4. Fractions of sources with di#erent spectral features.
Spectral class z mean z min z max Fraction
emission 1.131 0.117 5.828 46%
absorption 0.950 0.366 1.910 16%
em. & abs. 0.897 0.382 1.317 12%
stars 0.000 0.000 0.000 4%
unclassified ­ ­ ­ 22%
5.4. High redshift galaxies
As discussed in Sect. 2, the target selection includes mainly low redshift objects (z < 2). For three galaxies, however, a redshift
larger than four was measured: the galaxy GDS J033240.01 - 274815.0 at z = 5.828 the only i 775 ­dropout (see Sect. 2) actually
targeted in the present observations and two serendipitously­observed high redshift sources, GDS J033228.84 - 274132.7 and
one object at # = 3 h 32 m 28.94 s , # = -27 # 41 # 28.19 ## not present in the catalog v1.0, measured at z = 4.800 and z = 4.882,
respectively.
The i­dropout candidate has been observed with both the Keck and VLT telescopes (Dickinson et al. 2004a). In Figure 12
the FORS2 spectrum of the i­dropout source is shown. The Ly # line is clearly detected at z = 5.828 and shows the blue cut--o#
characteristic of high--redshift Ly # emitters and the Ly # forest continuum break.
Figure 13 shows a peculiar system of three sources: two emission­line sources above (#1.5 arcsecond) and below (#3 arcsec­
ond) the main galaxy GDS J033228.88 -274129.3, clearly visible in the ACS color image and in the two dimensional spectrum.
The same target has been observed in two di#erent masks adopting the same orientation of the slits. The total exposure time is
#43 ks. The extracted one dimensional spectra are shown in the right side of the Figure 13.
The main galaxy GDS J033228.88 - 274129.3 has a redshift z = 0.733 with both emission and absorption lines measured
(quality flag ``A''): [O ##]3727, MgI, Ca H and K, g­band, etc. The bottom object (GDS J033228.84 - 274132.7) shows a solo­
emission line at 7052å (see the 1­D spectrum), and is not detected in the ACS B band, we interpret this line as Ly # at z = 4.800
with quality ``C''.
The source above GDS J033228.88 - 274129.3 is most probably a Ly # emitter at redshift z = 4.882 (quality ``B''). The
spectrum has been extracted subtracting the contamination of the tail of the main galaxy. After the subtraction the shape of the
spectrum shows the blue cut--o# and the Ly # forest continuum break, typical of the LBGs.
5.5. Dynamical masses of galaxies at z # 1
Three galaxies, GDS J033215.88 - 274723.1, GDS J033225.86 - 275019.7 and GDS J033230.71 - 274617.2, at redshift
z=0.896, 1.095 and z=1.307 respectively show a spatially resolved [O ##]3727 line with a characteristic ``tilt'' indicative of a high
rotation velocity (see Figure 14).
Various studies have been carried out on the internal kinematics of distant galaxies (Vogt at al. 1996, Vogt at al. 1997,
Moorwood et al. 2001, Pettini et al. 2001 and van Dokkum & Stanford 2001). Rigopoulou et al. 2002 have determined velocity
profiles with a medium resolution grating R#5000 of three galaxies at z#0.6 and one at z#0.8, detected by ISOCAM in the
HDF--S. For one object they have derived a rotational velocity of 460 km s -1 containing a mass of 10 12 M # (within a radius of 20
Kpc) significantly higher than the dynamical masses measured in most other local and high redshift spirals.
In the case of GDS J033215.88 - 274723.1, GDS J033225.86 - 275019.7 and GDS J033230.71 - 274617.2, the spectra, in
spite of the relatively low resolution # #860, clearly show a tilt of several pixels (corresponding to about 10å). The measured
velocity increases with increasing distance from the center of the objects reaching a value of the order of and greater than 400
km s -1 at the extremes. For the object GDS J033225.86 - 275019.7 we have measured a displacement between the two extreme
peaks of 11.5å (top panel of the Figure 14), while a displacement of 9.6å has been measured in the case of GDS J033215.88 -
274723.1 (middle panel of the Figure 14)
Assuming that the observed velocity structure is due to dynamically­relaxed rotation, then it is possible to estimate the dy­
namical mass for the three galaxies shown in Figure 14 (e.g. Lequeux (1983)): 1.6
sin 2 (i) â10 11 M # for the galaxy GDS J033215.88 -
274723.1 (within a radius of 7.8 Kpc) and 3.1
sin 2 (i) â10 11 M # for the galaxy GDS J033225.86 - 275019.7 (within a radius of 9.8
Kpc). The noisy spectrum of the galaxy GDS J033230.71 - 274617.2 allows us to roughly measure a dynamical mass of the
order of 1.5
sin 2 (i) â10 11 M # (within a radius of 7.5 Kpc). The estimates should be considered a lower limit to the total dynamical mass
because more external parts of the rotating structure might have a lower surface brightness and remain undetected.

E. Vanzella et al.: The Great Observatories Origins Deep Survey 19
Fig. 9. Redshift distribution for the spectroscopic sample with quality A, B and C (23 redshift determinations out of 224 have
quality C). Three objects at z>4 are not shown in the histogram.
5.6. GDS J033210.93 - 274721.5: a spectrum contaminated by a nearby galaxy.
The spectrum of the galaxy GDS J033210.93 - 274721.5 simultaneously shows features corresponding to the redshifts z=1.222
and z=0.417 (Figure 15). The origin of the overlap is the presence of a nearby galaxy (z 850 = 19.98, GDS J033210.92-274722.8)
o#set by 1.3 arcsecond with a redshift z = 0.417. Light from the brighter z = 0.417 galaxy contaminates the spectrum of the
fainter (z 850 = 22.19), higher redshift galaxy GDS J033210.93 - 274721.5 (see Figure 15). Such cases may represent a problem
and a source of error in large spectroscopic surveys, which require an highly automated data processing. A possible solution is
to evaluate a priori on the basis of imaging what are the cases subject of light contamination requiring a ``special'' reduction.
Alternatively, color­redshift diagrams (such as Figure 7), a comparison of spectroscopic and photometric redshifts or similar
diagnostics are required to carry out the necessary data quality control and identify possible misidentifications.

20 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Fig. 10. The spatial distribution of the galaxies at z # 1.61 in the CDF­S. The background image is an exposure in the R band
obtained with the ESO wide­field imager (WFI). North is up and east on the left. The squares represent the FOV of the FORS2
pointings. The five FORS2 targets are given by their coordinates, and the three K20 sources with the identifiers: OBJ 00235,
OBJ 00237 and OBJ 00270. The numbers 31, 46, 60, 67, show the positions of z # 1.61 X­ray sources (see text).
6. Conclusions
In the framework of the Great Observatories Origins Deep Survey a large sample of galaxies in the Chandra Deep Field South
has been spectroscopically targeted. A total of 303 objects with z 850 # < 25.5 has been observed with the FORS2 spectrograph at
the ESO VLT providing 234 redshift determinations. From a variety of diagnostics the measurement of the redshifts appears to
be highly accurate (with a typical # z = 0.001) and reliable (with an estimated rate of catastrophic misidentifications at most few
percent). The reduced spectra and the derived redshifts are released to the community (http : //www.eso.org/science/goods/).
They constitute an essential contribution to reach the scientific goals of GOODS, providing the time coordinate needed to delin­
eate the evolution of galaxy masses, morphologies, and star formation, calibrating the photometric redshifts that can be derived
from the imaging data at 0.36­8µm and enabling detailed studies of the physical diagnostics for galaxies in the GOODS field.
Acknowledgements. We are grateful to the ESO sta# in Paranal and Garching who greatly helped in the development of this programme.
The work of DS was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. L.A.M.
acknowledges support by NASA through contract number 1224666 issued by the Jet Propulsion Laboratory, California Institute of Technology
under NASA contract 1407. We thank the ASI grant I/R/088/02 (SC, MN, EV).

E. Vanzella et al.: The Great Observatories Origins Deep Survey 21
Fig. 11. Two dimensional spectra of 5 galaxies at z=1.61. The [O ##]3727 emission line is marked with a circle at 9727.5å. The
absorption sky feature (#7600å, A band) is indicated with an arrow. It is worth to note the optimal red sensitivity of FORS2.
References
Abraham, R., G., van den Bergh, S., Glazebrook, K., Ellis, R., S., Santiago, B., X., Surma, P., Gri#ths, R., E., 1996, ApJ, 107, 1
Bahcall, J.N., Schmidt, M., Soneira, R.M. 1982, ApJ, 258, 17
Bohlin, R.,C., Colina, L., Finley, D., S., 1995, AJ, 110, 1316
Cimatti, A., Mignoli, M., Daddi, E., et al. 2002, A&A, 392, 395
Coleman, G., D., Wu, C.­C., & Weedman, D., W., 1980, ApJS, 43, 393
Dickinson et al. 2003, in the proceedings of the ESO/USM Workshop ''The Mass of Galaxies at Low and High Redshift'' (Venice, Italy, October
2001), eds. R. Bender and A. Renzini, astro­ph/0204213
Dickinson, M., et al., 2004, ApJ, 99, 122
Giavalisco, M., et al. 2004, ApJ, 600, L93
Giavalisco, M., Dickinson, M., Ferguson, H. C., Ravindranath, S., Kretchmer, C., Moustakas, L. A., Madau, P., Fall, S. M., Gardner, Jonathan
P., Livio, M., Papovich, C., Renzini, A., Spinrad, H., Stern, D., Riess, A., 2004, ApJ, 600, 103
Gilli, R., Cimatti, A., Daddi, E., Hasinger, G., Rosati, P., Szokoly, G., Tozzi, P., Bergeron, J., Borgani, S., Giacconi, R., Kewley, L., Mainieri,
V., Mignoli, M., Nonino, M., Norman, C., Wang, J., Zamorani, G., Zheng, W., Zirm, A., 2003, ApJ, 592, 721
Le Fevre, O., Vettolani, G., Paltani, S., Tresse, L., Zamorani, G., Le Brun, V., Moreau, C., and the VIMOS VLT Deep Survey team, submitted
to A&A, (astro­ph/0403628)
Lequeux, J. 1983, A&A, 125, 394
Moorwood A.F.M., van der Werf, P.P, Cuby, J.G., Oliva, E., 2000, A&A, 362, 9
Mobasher, B., Idzi, R., Bentez, N., Cimatti, A., Cristiani, S., Daddi, E., Dahlen, T., Dickinson, M., et al., 2004, ApJ, 600, 167
Oke, J.B., et al., 1995, PASP, 107, 375
Pettini, M., Shapley, A. E., Steidel C. C., Cuby, J.­G., Dickinson, M., A. F. M. Moorwood, Adelberger, K. L., Giavalisco, M., 2001, ApJ, 588,
65
Renzini et al. 2002, in the proceedings of the ESO/USM Workshop ''The Mass of Galaxies at Low and High Redshift'' (Venice, Italy, October
2001), eds. R. Bender and A. Renzini
Riess, A.G.,2 Strolger, L.­G., Tonry, J., Casertano, S., Ferguson, H.C., et al., 2004, ApJ, 607, 665
Rigopoulou, D., Franceschini, A., Aussel, H., Genzel, R., Thatte, N., Cesarsky, C. J., 2002, ApJ, 580, 789
Steidel, C.C., Adelberger, K.L., Giavalisco, M., Dickinson, M., Pettini, M., 1999, ApJ, 519, 1
Szokoly, G., P., Bergeron, J., Hasinger, G., Lehmann, I., Kewley, L., Mainieri, V., Nonino, M., Rosati, P., Giacconi, R., Gilli, R., Gilmozzi, R.,
Norman, C., Romaniello, M., Schreier, E., Tozzi, P., Wang, J., X., Zheng, W., Zirm, A., 2004, (astro­ph/0312324)
van Dokkum, P.G., & Stanford, S.A. 2001, ApJ, 562, 35
Vogt, P.N., et al. 1996, ApJ, 465, L15
Vogt, P.N., et al. 1996, ApJ, 479, L121
Warmels, R.H.: 1991, ``The ESO­MIDAS System'', in Astronomical Data Analysis Software and Systems I , PASP Conf. Series, Vol. 25, p.
115.

22 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Fig. 12. VLT spectrum of the i 775 --dropout galaxy GDS J033240.01­274815.0.

E. Vanzella et al.: The Great Observatories Origins Deep Survey 23
Fig. 13. Simultaneous spectrum of three sources in the slit. On the right of the figure, the 1D spectra of the z=0.733 main galaxy
GDS J033228.88 - 274129.3, the single emission line # 3 arcsecond below (GDS J033228.84 - 274132.7) and the object # 1.5
arcsecond above are shown. The left­hand panel shows the ACS color image, 5 arcsec on a side. North is up, east is to the left.
The bottom panel shows the 2D spectrum, with the spatial profile obtained by collapsing 80 columns (256 å), centered at 7150å,
shown to the right. Candidate serendipitous Ly # emission lines are clearly marked. The object above the target source shows faint
continuum reward of the emission line.

24 E. Vanzella et al.: The Great Observatories Origins Deep Survey
Fig. 14. Three examples of tilted [O ##]3727 emission line at redshift around 1. The two dimensional FORS2 spectra are shown
(object and sky lines). In the first two spectra (top and middle) a zoom of the [O ##]3727 emission line is shown (the white
rectangle underline the region where the Gaussian fit has been performed to derive the line peak, small black crosses), in the
bottom spectrum the line is too faint to calculate a reliable peak (this object has been serendipitously­identified). In the right side
of the spectra the ACS images of the galaxies and the slits orientation are shown.

E. Vanzella et al.: The Great Observatories Origins Deep Survey 25
Fig. 15. The light merged case, two objects at di#erent redshift superimposed in the slit (marked with white lines in the
left panel). In the right panel the same extracted spectrum with di#erent identifications. An elliptical galaxy (the target,
GDS J033210.93 - 274721.5) at z=1.222 clearly identified with the Ca H and K, H#, MgI (quality flag ``A''). The bright bluer
object (GDS J033210.92 - 274722.8) shows absorption and emission lines: Ca H, [O ###]5007, Na, H# at z = 0.417 (quality flag
``B''). The Ca K is contaminated by the sky line #5577å.