---
abstract: 'We present the results of spectroscopic observations of targets discovered during the first two years of the ESSENCE project. The goal of ESSENCE is to use a sample of $\sim$200 Type Ia supernovae (SNe Ia) at moderate redshifts $(0.2 \lesssim z \lesssim 0.8)$ to place constraints on the equation of state of the Universe. Spectroscopy not only provides the redshifts of the objects, but also confirms that some of the discoveries are indeed SNe Ia. This confirmation is critical to the project, as techniques developed to determine luminosity distances to SNe Ia depend upon the knowledge that the objects at high redshift are the same as the ones at low redshift. We describe the methods of target selection and prioritization, the telescopes and detectors, and the software used to identify objects. The redshifts deduced from spectral matching of high-redshift SNe Ia with low-redshift SNe Ia are consistent with those determined from host-galaxy spectra. We show that the high-redshift SNe Ia match well with low-redshift templates. We include all spectra obtained by the ESSENCE project, including 52 SNe Ia, 5 core-collapse SNe, 12 active galactic nuclei, 19 galaxies, 4 possibly variable stars, and 16 objects with uncertain identifications.'
author:
- 'Thomas Matheson, Stéphane Blondin, Ryan J. Foley, Ryan Chornock, Alexei V. Filippenko, Bruno Leibundgut, R. Chris Smith, Jesper Sollerman, Jason Spyromilio, Robert P. Kirshner, Alejandro Clocchiatti, Claudio Aguilera, Brian Barris, Andrew C. Becker, Peter Challis, Ricardo Covarrubias, Peter Garnavich, Malcolm Hicken, Saurabh Jha, Kevin Krisciunas, Weidong Li, Anthony Miceli, Gajus Miknaitis, Jose Luis Prieto, Armin Rest, Adam G. Riess, Maria Elena Salvo, Brian P. Schmidt, Christopher W. Stubbs, Nicholas B. Suntzeff, and John L. Tonry'
title: 'Spectroscopy of High-Redshift Supernovae from the ESSENCE Project: The First Two Years'
---

Introduction
============

The revolution wrought in modern cosmology using luminosity distances of Type Ia supernovae (SNe Ia) [@schmidt98; @riess98; @perlmutter99; @riess01; @knop03; @tonry03; @barris2304; @riess04b] relies upon the fact that the objects so employed are, in fact, SNe of Type Ia. Although the light-curve shape alone is useful [e.g., @barris04], the only way to be sure of the true nature of an object as a SN Ia is through spectroscopy. The calculation of luminosity distances depends upon the high-redshift objects being SNe Ia so that low-redshift calibration methods can be employed. The classification scheme for SNe is based upon the optical spectrum near maximum [see @filippenko97 for a review of SN types], so rest-wavelength optical spectroscopy is necessary to properly identify SNe Ia at high redshifts. Despite this significance, relatively little attention has been paid to the spectroscopy of the high-redshift SNe Ia, with some notable exceptions [@coil00]. Other publications that include high-redshift SN Ia spectra include @schmidt98, @riess98, @perlmutter98, @leibundgut01, @tonry03, @barris2304, @blondin04, @riess04b, and @lidman04.

In addition to providing evidence for the acceleration of the expansion of the Universe, it was recognized at an early stage that high-redshift SNe Ia could put constraints on the equation of state for the Universe [@garnavich98], parameterized as $w =
P/(\rho c^2)$, the ratio of the dark energy’s pressure to its density. To further explore this, the ESSENCE project was begun. The ESSENCE (Equation of State: SupErNovae trace Cosmic Expansion) project is a five-year ground-based SN survey designed to place constraints on the equation-of-state parameter for the Universe using $\sim$200 SNe Ia over a redshift range of $0.2 \lesssim z \lesssim 0.8$ [see @miknaitis05; @smith05 for a more extensive discussion of the goals and implementation of the ESSENCE project].

Spectroscopic identification of optical transients is a major component of the ESSENCE project. In addition to confirming some targets as SNe Ia, the spectroscopy provides redshifts, allowing the derived luminosity distances to be compared with a given cosmological model. So many targets are discovered during the ESSENCE survey that a large amount of telescope time on 6.5 m to 10 m telescopes is required. In the first two years of the program, we were fortunate enough to have been awarded over 60 nights at large-aperture telescopes. Even with this much time, though, our resources were insufficient to spectroscopically identify all of the potentially useful candidates. This remains the most significant limiting factor in achieving the ESSENCE goal of finding, identifying, and following the desired number of SNe Ia with the appropriate redshift distribution.

Nonetheless, spectroscopic observations of ESSENCE targets in the time available have been successful, with almost fifty SNe Ia clearly identified, and several more characterized as likely SNe Ia. Other identifications include core-collapse SNe, active galactic nuclei (AGNs), and galaxies. The galaxy spectra may include an unidentified SN component.

This paper will describe the results of the spectroscopic component of the first two years of the ESSENCE program. Year One refers to our 2002 Sep-Dec campaign; Year Two was our 2003 Sep-Dec campaign. In Section \[target\], we describe the process of target selection and prioritization. Section \[obs\] describes the technical aspects of the observations. We discuss target identification in Section \[id\]. The summary of results in terms of types of objects and success rates is given in Section \[results\]. In addition, we present in Section \[results\] all of the spectra obtained, including those of the SNe Ia (with low-redshift templates), core-collapse SNe, AGNs, galaxies, stars, and objects that remain unidentified.

Target Selection\[target\]
==========================

The ESSENCE survey uses the Blanco 4 m telescope at CTIO with the MOSAIC wide-field CCD camera to detect many kinds of optical transients [@smith05]. Temporal coverage helps to identify solar-system objects such as Kuiper Belt Objects (KBOs) and asteroids. Known AGNs and variable stars can also be eliminated from the possible SN Ia list. The remaining transients are all potentially SNe. They are also faint, requiring large-aperture telescopes to obtain spectra of the quality necessary to securely identify the object. Exposure times on 8-10 m telescopes are typically about half an hour, but can be as much as two hours. Such telescope time is difficult to obtain in quantity, so not all of the detected transients can be examined spectroscopically. We apply several criteria to prioritize target selection for spectroscopic observation.

The first step in sorting targets is based upon the spectroscopic resources available. The equatorial fields used for the ESSENCE program are accessible from most major astronomical sites, so the main concern with matching targets to spectroscopic telescopes is the aperture size of the telescope. The ESSENCE targets are generally in the range $18 \lesssim m_R \lesssim 24$ mag. When 8-10 m telescopes are unavailable, the fainter targets become lower in priority. The limit for low-dispersion spectroscopy to identify SNe with the 6.5 m telescopes is $m_R \approx 22-23$ mag, although this will vary with weather conditions and seeing. If the full range of telescopes is available, then targets are prioritized by magnitude for observation at a given telescope. The longitudinal distribution of spectroscopic resources can be important if confirmation of a high-priority target is made during a night when multiple spectroscopic resources are available. By the time a target is confirmed, the fields may have set for telescopes in Chile, while they are still accessible from Hawaii. This requires active, real-time collaboration between the group finding SN candidates and those running the spectroscopic observations.

One advantage of the ESSENCE program is that fields are imaged in multiple filters, allowing for discrimination of targets by color. @tonry03 present a table of expected SN Ia peak magnitudes as a function of redshift; see also @poznanski02, @galyam04, @riess04a, @strolger04, and @smith05 for discussions of color selection for SN candidates. Given apparent $R$-band and $I$-band magnitudes, one can calculate the $R-I$ color and compare that with an expected color for those magnitudes. The cadence of the ESSENCE program (returning to the same field every four days) will likely catch SNe at early phases (i.e., before maximum brightness). Early core-collapse SNe are bluer than SNe Ia, as are AGNs. For example, when selecting for higher-redshift targets, objects with $R-I \lesssim 0.2$ mag were considered unlikely to be SNe Ia, while objects with $R-I \gtrsim 0.4$ mag were made high priority for spectroscopic observation. The exact values of $R-I$ used for selection depended on the observed $R$-band magnitude. This method was used more consistently in the last month of Year Two, reducing the fraction of spectroscopic targets that were identified as AGNs from $\sim10\%$ over the lifetime of the project to $\sim5\%$ during that month.

The cadence of the ESSENCE program is designed to catch SNe early. At the start of an observing campaign or after periods of bad weather, though, we may have missed SNe during their rise to maximum brightness and only caught them while they are declining from maximum. If a target is brightening, then it is a higher priority than one that is not. This prioritization by phase of the SN became even more important when our [*Hubble Space Telescope*]{} ($HST$) program to observe some of the ESSENCE SNe Ia was active [see @krisciunas05]. The response time of $HST$ for a new target, even if the rough position on the sky is known from our chosen search fields, is still on the order of several days. To ensure that $HST$ was not generally looking at SNe Ia after maximum brightness, we would emphasize targets for spectroscopic identification that appeared to be at an early epoch. In addition, we chose fainter objects, as higher-redshift SNe Ia were a prime motivation for $HST$ photometry. The $HST$ observations, while still targets of opportunity, were scheduled for specific ESSENCE search fields, so new targets in those fields were given the highest priority.

The position of the SN in the host galaxy also influences the priority for observation. An optical transient located at the core of a galaxy is often an AGN, rather than an SN. The color selection described above is a less-biased predictor. In addition, even if the object is an SN, the signal of the SN itself is diluted by the light of the galaxy, making proper identification difficult. Objects that are well-separated from the host galaxy are given a higher priority. Being too far from the galaxy can, however, present another problem—the difficulty in obtaining a spectrum of the host in addition to the SN. Without a high signal-to-noise ratio (S/N) spectrum of the host, there is no precise measure of the redshift. This is especially true if the host galaxy cannot be included in the slit with the target, either to orient the slit at the parallactic angle or as a result of other observational constraints. In addition, host galaxies can be faint, so the large luminosity contrast with the SN makes detection of the host problematic (the so-called “hostless” SNe), although we did not reject any candidates solely for this reason. The best compromise is to have an object well separated from the host, but with the host still in the spectrograph slit. Without narrow-line features from the host (either emission or absorption lines), the redshift can be difficult to determine. This lack of a host-galaxy spectrum became less of a concern, though, as we found that the SN spectrum itself is a relatively accurate, if less precise, measure of the redshift (see discussion below). The light curve alone can be used to estimate distances in a redshift-independent way [@barris04], but only with a well-sampled and accurate light curve.

The target selection process is complex and dynamic. Biases are introduced by some of the steps; for example, SN candidates near the centers of galaxies are less likely to be observed. Since the goal is to optimize the spectroscopic telescope time to identify SNe Ia in a specific redshift range, we have chosen these selection processes as our best compromise. The biases introduced may make the sample of SNe Ia identified problematic for uses in statistical studies of the nature of SNe Ia at high redshift.

Observations\[obs\]
===================

Spectroscopic observations of ESSENCE targets were obtained at a wide variety of telescopes: the Keck I and II 10 m telescopes, the VLT 8 m telescopes, the Gemini North and South 8 m telescopes, the Magellan Baade and Clay 6.5 m telescopes, the MMT 6.5 m telescope, and the Tillinghast 1.5 m telescope at the F. L. Whipple Observatory (FLWO). The spectrographs used were LRIS [@oke95] with Keck I, ESI [@sheinis02] with Keck II, FORS1 with VLT [@appenzeller98], GMOS [@hook02] at Gemini (North and South), IMACS [@dressler04] with Baade, LDSS2 [@mulchaey01] with Clay, the Blue Channel [@schmidt89] at MMT, and FAST [@fabricant98] at FLWO. Nod-and-shuffle techniques [@glaze01] were used with GMOS (North and South) and IMACS to improve sky subtraction in the red portion of the spectrum.

Standard CCD processing and spectrum extraction were accomplished with IRAF[^1]. Most of the data were extracted using the optimal algorithm of @horne86; for the VLT data, an alternative extraction method based upon Richardson-Lucy restoration [@blondin04] was employed. Low-order polynomial fits to calibration-lamp spectra were used to establish the wavelength scale. Small adjustments derived from night-sky lines in the object frames were applied. We employed IRAF and our own IDL routines to flux calibrate the data and, in most cases, to remove telluric lines using the well-exposed continua of the spectrophotometric standards [@wade88; @matheson00].

Target Identification\[id\]
===========================

Once a calibrated spectrum is available, the next step is to properly classify the object. For brighter objects that yield high S/N spectra, an SN is often easy to distinguish and classify. Most of the ESSENCE targets are faint enough to be difficult objects even for large-aperture telescopes. The resulting noisy spectra can be confusing. Even for well-exposed spectra, though, exact classification can occasionally still be challenging.

For SNe, the classification scheme is based upon the optical spectrum near maximum brightness [@filippenko97]. Type II SNe are distinguished by the presence of hydrogen lines. The Type I SNe lack hydrogen, and are further subdivided by the presence or absence of other features. The hallmark of SNe Ia is a strong $\lambda6355$ absorption feature. Near maximum brightness, this absorption is blueshifted by $\sim$10,000 km s$^{-1}$ and appears near 6150 Å. In SNe Ib, this line is not as strong, and the optical helium series dominates the spectrum. The SNe Ic lack all these identifying lines.

At high redshift, the $\lambda6355$ feature is at wavelengths inaccessible to optical spectrographs, so the identification relies upon the pattern of features in the rest-frame ultraviolet (UV) and blue-optical wavelengths. The H&K $\lambda\lambda3934, 3968$ doublet is a distinctive feature in SNe Ia, but it is also present in SNe Ib/c, so the overall pattern is important for a clear identification as a SN Ia. Other important features to identify SNe Ia include $\lambda4130$, $\lambda4481$, $\lambda4555$, $\lambda4560$, $\lambda4816$, and $\lambda5051$ [see, e.g., @coil00; @jeffery92; @kirshner93; @mazzali93].

The first stage of classification is done by eye. Drawing upon the extensive experience of the spectroscopic observers associated with ESSENCE, we can provide a solid evaluation of the spectrum. Objects such as AGNs and normal galaxies are fairly easy to distinguish. The SNe Ia are also often clear, but some fraction of the data will require more extensive analysis. The first step is simply to make certain that the collective expertise is used, rather than just the individual at the telescope. Spectroscopic results are widely disseminated via e-mail and through an internal web page, allowing rapid examination of any questionable spectrum by the entire collaboration. Broad discussion often leads to a consensus.

In addition to the traditional by-eye approach, we employ automated comparisons. If the object is likely to be a SN Ia, and if the S/N ratio is sufficiently high and the rest-wavelength coverage appropriate, we can use a spectral-feature aging routine [@riess97] that compares specific components of the SN Ia spectrum with a library of SN Ia spectra at known phases. This can pin down the epoch of a SN Ia to within a few days. This program, though, is limited to normal SNe Ia (i.e., not spectroscopically peculiar objects, which are often overluminous or underluminous). In addition, it does not identify objects that do not match the Type Ia SN spectra in the library.

For a more general identification routine, we use an algorithm called SuperNova IDentification [SNID; @tonry05]. This program takes the input spectrum and compares it against a library of objects of many types. The templates include SNe Ia of various luminosity classes and at a range of ages, core-collapse SNe, and galaxies. The offset in wavelength caused by redshift is a free parameter, so the output includes an estimate of the redshift of the object. The routine compares the input with the library and returns the most likely match. The comparison is weighted by the amount of overlap between the input spectrum and the template. For a subset of the objects ($\lesssim 10\%$), the SNID comparison is not optimal. This may be the result of contamination by galaxy light, the lack of a matching template in the SNID library, poor S/N of the spectrum in question, or a problem in the routine. All SNID comparisons are checked by eye for a qualitative judgment of the goodness of fit.

The redshift of the object can also be directly determined from the spectrum itself if narrow emission or absorption lines associated with the host galaxy are present. Occasionally, observations are set up to include the host galaxy in the spectrograph slit specifically for the purpose of obtaining a redshift. If there is a strong enough signal of a galaxy spectrum, but no clearly identifiable narrow emission or absorption lines, cross-correlation with an absorption template could be used. For the spectra that had narrow emission or absorption lines (or were cross-correlated with a template), we report the redshift to three significant digits. If the redshift determination is based solely on a comparison of the SN spectrum to a low-redshift analog, the redshift is less certain, and we only report the value to two significant digits.

For the objects with a more precise redshift derived from the host galaxy, we can compare the galactic redshift with the value of the redshift estimated by SNID. Figure \[snidfig\] shows that the SNID redshifts agree well with the galaxy redshifts. Thus, for objects without precise redshifts from host galaxy spectra, the SNID redshifts can be used as reliable substitutes. In the cases where SNID did not agree with a galaxy redshift, we forced the redshift to match in order to find the best-fitting template, but all the supernova-based redshifts reported in this paper correspond to the “un-forced” SNID result.

Results\[results\]
==================

The results of our spectroscopic observations during the first two years of the ESSENCE program are summarized in Table \[resulttable\]. There are 46 SNe Ia (and 5 additional likely SNe Ia), along with 5 core-collapse SNe. Note also that there were 54 transients in the first two years that were not observed spectroscopically. Through the target selection methods described in Section \[target\], we were able to prioritize the more likely candidates, but many of these were not observed solely because of the lack of sufficient spectroscopic resources. This became more of an issue toward the end of Year Two, when good weather and increasingly efficient detection algorithms increased the number of transients discovered.

The goal of the ESSENCE project is to find $\sim$200 SNe Ia over the redshift range $0.2 \lesssim z \lesssim 0.8$. In Figure \[zdistfig\], we show the actual distribution in redshift of the SNe Ia from the ESSENCE project that are spectroscopically confirmed. There are SNe over the entire targeted redshift range, although there are fewer at the high end ($z \gtrsim 0.6$). A significant fraction of the signal of $w$ is accessible at $z \approx
0.5$ [@miknaitis05], but a goal for the last three years of the program is to ensure that the SNe Ia observed spectroscopically are distributed optimally over our targeted redshift range. This highlights the importance of the 8-10 m telescopes such as Gemini, the VLT, and Keck that are critical to spectroscopy of the faint objects at the high-redshift end of our range.

Both SNID and the spectral-feature aging method described in Section \[id\] give an indication of the age of the SN Ia. Light curves will provide a more precise measure of the age of the SN at the time of the spectroscopy, but an estimate of the epoch of the spectrum to within a few days is possible from the spectral features alone. Figure \[agedistrib\] shows the distribution in age (relative to maximum brightness) at the time of spectroscopy (not discovery, as spectra are often taken up to several days after discovery). In the 15 cases[^2] where we have spectra of the same SN Ia at multiple epochs, the relative ages are consistent with the times of the spectroscopic exposures (also considering the effects of cosmological time dilation and probable errors of the fits of $\sim\pm3$ days). There is one exception to this consistency (b027), but at later epochs when the spectra are changing less.

Table \[sntable\] is a list of all ESSENCE targets that were selected for spectroscopic identification. The results for these first two years include 52 SNe Ia or likely SNe Ia (Figure 4), 4 SNe II (Figure \[IIfig\]), 1 SN Ib/c (Figure \[IIfig\]), 12 AGNs (Figure 6), 4 possibly variable stellar objects (Figure \[starfig\]), 19 galaxies (Figure 8), and 16 objects of unknown classification (Figure 9). There were 10 objects for which we pointed the telescope at the target and did not get a spectrum, either because of poor sky conditions or the target was actually a solar-system object and had moved out of the field.

No attempt has been made to remove host-galaxy contamination for any object presented in Figures 4 and 5. The amount of galaxy light is significant for some objects (e.g., f221 on Figure 4d). In addition, no extinction corrections have been applied, either for Galactic reddening or extinction in the host galaxy. Given the Galactic latitudes of the ESSENCE fields [@smith05] and our preference for targets well separated from the host galaxy, the effects of extinction are likely to be minimal [@blondin05; @foley05].

For each SN Ia in Figure 4, the best match low-redshift comparison spectrum as determined using SNID is included. In general, the high-redshift SNe Ia look very similar to those at low redshift, implying that there are no significant evolutionary effects. Future papers will deal in much greater detail with the comparison with low-redshift SNe Ia, as well as removal of galactic contamination and the effects of extinction [@blondin05; @foley05].

While most of the high-redshift SNe Ia appear to be normal, there are some examples of peculiar SNe Ia. Both b004 (SN 2002iv; Figure 4a) and d083 (SN 2003jn; Figure2b) show strong similarities with SN 1991T, an overluminous Type Ia SN [@filippenko92; @phillips92]. Given the high rate of peculiar SNe Ia at low redshift [@weidong01], we would expect to find such objects in a high-redshift sample.

We note that in Figure 4, there are several examples of high-redshift SNe Ia from the ESSENCE sample for which the low-redshift template appears to be a poor match. Examples include d086 (2003-10-27), b008 (2002-11-06), e149, and b022 (2002-12-05) . The most likely explanation for this is that the templates included in SNID do not cover the complete range of possibilities, although problems with the spectrum (e.g., poor S/N or sky subtraction) may also play a role. Rather than perform a non-objective search for the best match, we leave these as examples of the current limitations in SNID. We plan to expand the SNID templates to eliminate such occurrences in the future.

Two unusual cases in the sample of SNe Ia spectra are e315 (SN 2003ku) and b004 (SN 2002iv). They are the only SNe for which the redshift determination in SNID was ambiguous. For e315, if we assume that it is a Ia, then the best fit redshift is 0.79, but a fit at a redshift of 0.41 is only marginally worse. All other SNe Ia spectra in the ESSENCE sample had redshifts determined by SNID that were unambiguous. If we rely on the spectrum alone, the SNID result of $z=0.79$ is what we would choose, and so we report it in this paper. Analysis presented by @krisciunas05 shows that neither of the redshifts suggested by SNID gives a very satisfactory fit to the photometry. In the case of b004, the SNID result is $z=0.39$, while the fit when $z=0.231$, known from galaxy features, is almost as good. As b004 is similar to SN 1991T (see above), the lack of good templates in SNID may be the source of this discrepancy. Correlation of b004 with SN 1991T templates yields a redshift of $z=0.22$, close to the value derived from the host galaxy. This highlights some of the perils of identifying optical transients with low S/N spectra. Sometimes the spectrum alone is not enough. A consideration of all the information (spectrum, light curve, host galaxy, etc.) is necessary to draw the appropriate conclusion.

Among the unknown spectra (Figure 9a), there are three spectra that require some discussion. For e106, the redshift is known because the host galaxy was also observed. The emission line appearing at the observed wavelength of 9457 Å in f213 is real. If this is H$\alpha$ then $z=0.44$; if it is \[\] $\lambda$5007, then $z=0.89$. There is an apparent doublet absorption line in e103 at an observed wavelength of 5240 Å. We interpret this as $\lambda$2800 at a redshift of 0.871, implying that this object has a redshift at least that high. It is likely to be a high-redshift AGN, but we do not have enough information to move it out of the unknown category.

Conclusions
===========

We have presented optical spectroscopy of the targets selected for follow-up observations from the first two years of the ESSENCE project. As the target selection process has improved, we have increased our yield of SNe Ia that are needed for the primary purpose of the ESSENCE project—measuring luminosity distances to $\sim$200 SNe Ia over the redshift range $(0.2 \lesssim z \lesssim 0.8)$. The SNe Ia show strong similarities with low-redshift SNe Ia, implying that there are no significant evolutionary changes in the nature of Type Ia SNe and that our methods for identifying objects have been successful. This is also shown by the concordance of redshifts derived from SN spectra and those found from the host galaxy itself. Over the next three years, ESSENCE will continue to discover high-redshift SNe Ia. With enough spectroscopic telescope time, we plan to be even more successful in correctly identifying Type Ia SNe than we have been during the first two years.

All spectra presented in this paper will be made publicly available upon publication.

We would like to thank the staffs of the Paranal, Gemini, Keck, Las Campanas, MMT, F. L. Whipple, and Cerro Tololo Inter-American Observatories for their extensive assistance and support during this project. We would also like to thank Warren Brown and Craig Heinke for assistance with the MMT observations. This work is supported primarily by NSF grants AST-0206329 and AST-0443378. In addition, A.V.F.’s group at UC Berkeley acknowledges NSF grant AST-0307894. C.W.S thanks the McDonnell Foundation and Harvard University for their support. A.C. acknowledges the support of CONICYT (Chile) through FONDECYT grants 1000524 and 7000524.

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[rrr|r]{}

Ia & 15 & 31 & 46\
Ia? & 0 & 6 & 6\
II & 2 & 2 & 4\
Ib/c& 0 & 1 & 1\
AGN & 4 & 8 & 12\
Gal & 7 & 12 & 19\
star& 2 & 2 & 4\
N.S.& 5 & 5 & 10\
Unk.& 2 & 14 & 16\
N.A.& 13 & 43 & 54\
Total & 50 & 124 & 174\

[llllllllllll]{}

a002.wxc1\_04 & & 2002-12-06.03 & VLT & Gal & 0.316 &&& &&& 900\
b001.wxc1\_14 && 2002-11-06.27 & KII/ESI & Unk &&& && & 23.6 & 1600\
b001.wxc1\_14 && 2002-11-11.32 & KI/LRIS & Unk &&&&& & 23.6 & 1800\
b001.wxc1\_14 && 2002-12-05.26 & GMOS & Unk &&&& && 23.6 & 2x1800\
b002.wxh1\_01 && 2002-11-01.44 & KII/ESI & star &&&& && & 900\
b003.wxh1\_14 & 2002iu & 2002-11-01.43 & KII/ESI & Ia && 0.11 & 2 & 94S & good & 18.9 & 600\
b004.wxt2\_06 & 2002iv & 2002-11-02.45 & KII/ESI & Ia & 0.231 & 0.39 & -4 & 95ac & good & 20.9 & 1200\
b005.wxd1\_11 & 2002iw & 2002-11-03.16 & MMT & Gal & 0.205 &&&&& 21.8 & 3x1800\
b005.wxd1\_11 & 2002iw & 2002-11-06.32 & KII/ESI & Gal & 0.205 &&&&& 21.8 & 1800\
b006.wxb1\_16 & 2002ix & 2002-11-03.10 & MMT & N.S. &&&&&& 22.2 &\
b006.wxb1\_16 & 2002ix & 2002-11-06.24 & KII/ESI & II? &&&&&& 22.2 & 1800\
b008.wxc1\_05 & 2002jq & 2002-11-06.29 & KII/ESI & Ia && 0.49 & -8 & 90N & poor & 21.9 & 1800\
b008.wxc1\_05 & 2002jq & 2002-12-04.27 & GMOS & Ia && 0.49 & +13 & 89B & good & 21.9 & 4x1800\
b010.wxv2\_07 & 2002iy & 2002-11-06.39 & KII/ESI & Ia && 0.59 & -1 & 92A & poor & 21.3 & 1800\
b010.wxv2\_07 & 2002iy & 2002-11-11.45 & KI/LRIS & Ia && 0.59 & +2 & 94ae & poor & 21.3 & 1800\
b010.wxv2\_07 & 2002iy & 2002-12-06.35 & GMOS & Ia && 0.59 & +13 & 89B & good & 21.3 & 5x1800\
b010.wxv2\_07 & 2002iy & 2002-12-07.22 & VLT & Ia & 0.587 & 0.59 & +17 & 95al & good & 21.3 & 2x1800\
b013.wxv2\_10 & 2002iz & 2002-11-06.45 & KII/ESI & Ia & 0.427 & 0.42 & -6 & 90N & good & 22.1 & 1800\
b013.wxv2\_10 & 2002iz & 2002-12-06.07 & VLT & Ia & 0.428 & 0.43 & +14 & 89B & good & 22.1 & 1800\
b014.wxv2\_15 && 2002-11-06.41 & KII/ESI & Gal & 0.268 &&& && 22.8 & 1800\
b015.wcx1\_09 && 2002-11-06.34 & KII/ESI & Gal & 0.207 &&& && & 1800\
b016.wxb1\_15 & 2002ja & 2002-11-09.33 & KII/ESI & Ia && 0.33 & +2 & 94ae & good & 22.2 & 1200\
b017.wxb1\_06 & 2002jb & 2002-11-09.31 & KII/ESI & Ia && 0.25 & +2 & 94ae & good & 21.4 & 1200\
b019.wxd1\_04 && 2002-11-09.35 & KII/ESI & Gal & 0.213 &&& && 22.2 & 1200\
b020.wye2\_01 & 2002jr & 2002-11-09.42 & KII/ESI & Ia && 0.43 & -9 & 91M & poor & 22.7 & 1800\
b020.wye2\_01 & 2002jr & 2002-12-09.39 & GMOS & Ia && 0.43 & +7 & 72E & good & 22.7 & 2x1800\
b022.wyc3\_03 & 2002jc & 2002-11-09.45 & KII/ESI & Ia && 0.52 & -7 & 90N & poor & 23.1 & 1800\
b022.wyc3\_03 & 2002jc & 2002-12-05.39 & GMOS & Ia && 0.52 & +4 & 96Z & good & 23.1 & 4x1800\
b023.wxu2\_09 & 2002js & 2002-11-11.57 & KI/LRIS & Ia && 0.54 & -7 & 89B & poor & 22.9 & 2100\
b023.wxu2\_09 & 2002js & 2002-12-03.41 & GMOS & Ia && 0.54 & +6 & 92A & good & 22.9 & 4x1800\
b024.wxc1\_16 && 2002-11-11.27 & KI/LRIS & VStar &&&& && 21.5 & 1800\
b025.wxa1\_05 && 2002-11-11.29 & KI/LRIS & N.S. &&&& && 22.2 & 1800\
b026.wxk1\_05 && 2002-11-11 & KI/LRIS & N.S. &&&& && 22.2 &\
b027.wxm1\_16 & 2002jd & 2002-11-11.45 & KI/LRIS & Ia & & 0.32 & +0 & 81B & good & 22.0 & 3600,1800\
b027.wxm1\_16 & 2002jd & 2002-12-06.07 & VLT & Ia && 0.32 & +13 & 89B & good & 22.0 & 1800\
b027.wxm1\_16 & 2002jd & 2002-12-09.27 & GMOS & Ia && 0.32 & +12 & 92G & good & 22.0 & 4x1800\
c002.wxp1\_14 && 2002-12-01 & Clay & N.S. &&&& && 22.4 &\
c002.wxp1\_14 && 2002-12-03 & GMOS & N.S. &&&& && 22.4 &\
c003.wxh1\_15 & 2002jt & 2002-12-02.13 & Clay & Ia && 0.56 & -7 & 89B & good & 22.6 & 2x1800\
c003.wxh1\_15 & 2002jt & 2002-12-07.29 & GMOS & Ia && 0.56 & +0 & 94S & good & 22.6 & 3x1800\
c005.wxb1\_10 & & 2002-12-06.05 & VLT & AGN & 0.249 &&& && & 900\
c012.wxu2\_16 & 2002ju & 2002-12-03.15 & Clay & Ia & 0.348 & 0.35 & -8 & 90N & good & 21.6 & 2x1800\
c012.wxu2\_16 & 2002ju & 2002-12-04.43 & GMOS & Ia & 0.348 & 0.35 & -8 & 90N & good & 21.6 & 3x1200\
c012.wxu2\_16 & 2002ju & 2003-01-05.33 & KII/ESI & Ia & 0.348 & 0.35 & +14 & 89B & poor & 21.6 & 1800\
c013.wxm1\_13 & & 2002-12-05 & GMOS & N.S. &&&& &&&\
c014.wyb3\_03 & 2002jv & 2002-12-07.12 & VLT & Gal & 0.221 &&& && 22.6 & 2x1800\
c014.wyb3\_03 & 2002jv & 2003-01-04.28 & GMOS & Gal & 0.221 &&& && 22.6 & 4x1800\
c015.wxv2\_02 & 2002jw & 2002-12-07.18 & VLT & Ia & 0.357 & 0.35 & +0 & 81B & good & 22.8 & 2x1800\
c015.wxv2\_02 & 2002jw & 2003-01-05.37 & KII/ESI & Ia & 0.356 & 0.38 & +12 & 89B & poor & 22.8 & 2400\
c016.wxm1\_04 & & 2002-12-07.07 & VLT & AGN & 0.845 &&& && 23.5 & 2x1800\
c020.wxt2\_15 && 2003-01-05.30 & KII/ESI & Unk & 0.650 &&& && 23.3 & 2x900\
c020.wxt2\_15 & & 2003-01-10.11 & VLT & Unk &&&& && 23.3 & 2x1800\
c022.wxu2\_15 & & 2003-01-04.09 & Clay & II? & 0.213 &&& && & 2x1200\
c023.wxm1\_15 & & 2003-01-03.07 & Clay & Ia & 0.399 & 0.42 & -8 & 90N & good & & 2x1200\
c024.wxv2\_05 & & 2003-01-03.12 & Clay & Gal & 0.317 &&& && & 1800\
c025.wxb1\_14 & & 2003-01-04.05 & Clay & AGN & 0.362 &&&&& & 600\
c028.wxu2\_16 & & 2003-01-04.13 & Clay & AGN & 2.02 &&&&& & 1800\
d009.waa6\_16 & & 2003-10-29.11 & VLT & Gal & 0.352 & && && & 1800\
d106.waa6\_16 & & 2003-10-31.01 & VLT & Gal & 0.353 & && && & 1800\
d010.waa6\_16 & 2003jp & 2003-10-30.03 & VLT & Ib/c && 0.08 & +35 & 87M & poor & 21.6 & 2x1800\
d029.waa6\_13 & & 2003-10-29.03 & VLT & AGN & 2.575 &&& && 21.6 & 2x1800\
d033.waa6\_10 & 2003jo & 2003-10-29.09 & VLT & Ia & 0.524 & 0.53 & -1 & 89B & good & 20.9 & 2x1800\
d033.waa6\_10 & 2003jo & 2003-11-23.05 & VLT & N.S. & 0.524 &&& && 20.9 & 2x1800\
d034.waa7\_10 & & 2003-10-28.29 & GMOS & AGN & 2.28 &&& && 21.4 & 2x1200\
d051.wcc8\_2 & & 2003-10-30.22 & VLT & Gal & 0.382 &&& &&& 1800\
d057.wbb6\_3 & 2003jk & 2003-10-30.15 & VLT & Unk && && && 20.9 & 2x1800\
d058.wbb6\_3 & 2003jj & 2003-10-31.07 & VLT & Ia & 0.583 & 0.58 & -1 & 92A & good & 23.1 & 2x1800\
d059.wcc5\_3 & & 2003-10-29.17 & VLT & Gal & 0.207 &&& && 19.2 & 2x1800\
d060.wcc7\_3 & & 2003-10-30.35 & VLT & M-star &&&& &&& 1800\
d062.wcc9\_3 & & 2003-10-29.26 & VLT & AGN & 2.42 &&& && 20.3 & 1800\
d083.wdd9\_12 & 2003jn & 2003-10-29.29 & VLT & Ia && 0.33 & -1 & 91T & good & 20.8 & 1800\
d084.wdd9\_11 & 2003jm & 2003-10-30.19 & VLT & Ia & 0.522 & 0.52 & +8 & 72E & good & 22.9 & 1800\
d085.waa5\_16 & 2003jv & 2003-10-28.37 & GMOS & Ia & 0.405 & 0.41 & +3 & 94ae & poor & 22.2 & 3x1200\
d086.waa5\_3 & 2003ju & 2003-10-27.06 & GMOS & Ia && 0.20 & -7 & 89B & poor & 21.6 & 3x600\
d086.waa5\_3 & 2003ju & 2003-11-27.10 & Baade & Ia && 0.20 & +13 & 89B & good & 21.6 & 3x1800\
d087.wbb5\_4 & 2003jr & 2003-11-01.18 & GMOS & Ia & 0.340 & 0.34 & +6 & 95E & good & 21.9 & 3x600\
d089.wdd6\_8 & 2003jl & 2003-10-31.34 & VLT & Ia & 0.429 & 0.43 & +6 & 95E & good & 22.4 & 1800\
d091.wcc1\_2 & & 2003-10-29.22 & VLT & Unk &&&& &&& 2x1800\
d093.wdd5\_3 & 2003js & 2003-10-29.96 & VLT & Ia & 0.363 & 0.36 & -6 & 90N & good & 22.0 & 923+600\
e142.wdd5\_3 & 2003js & 2003-11-23.21 & VLT & Ia & 0.363 & 0.36 & +12 & 95D & good & 22.0 & 3x1200\
d097.wdd5\_10 & 2003jt & 2003-10-29.32 & VLT & Ia && 0.45 & -5 & 90O & good & 22.0 & 1800\
d099.wcc2\_16 & 2003ji & 2003-11-01.23 & GMOS & Ia && 0.21 & +17 & 95bd & good & 20.9 & 3x600\
d100.waa7\_16 & 2003jq & 2003-10-24.21 & FLWO & Ia && 0.16 & +26 & 95al & good & 19.8 & 2x1800\
d115.wbb6\_11 & & 2003-10-28.43 & GMOS & Unk &&&& && 20.2 & 1200\
d117.wdd8\_16 & 2003jw & 2003-10-30.32 & VLT & Ia & 0.296 & 0.29 & -1 & 95E & good & 22.6 & 1800\
d123.wcc9\_16 & & 2003-10-30.27 & VLT & Gal & 0.500 &&& &&&\
d124.wcc9\_15 & & 2003-10-31.26 & VLT & AGN & 0.609 &&& && 20.5 & 1800\
d149.wcc4\_11 & 2003jy & 2003-10-31.10 & VLT & Ia & 0.339 & 0.34 & -5 & 90O & good & 22.7 & 1800\
d150.wcc1\_12 & & 2003-10-31.31 & VLT & Gal & 0.190 &&& &&&\
d156.wcc2\_4 & 2003jx & 2003-10-31.15 & VLT & Unk &&&& &&& 2x1800\
e018.wbb7\_2 & & 2003-11-19.05 & Clay & AGN & 0.181 &&& && 18.6 & 600\
e020.waa6\_9 & 2003kk & 2003-11-19.11 & Clay & Ia & 0.164 & 0.16 & -5 & 90O & good & 20.3 & 3x300\
e022.wbb7\_12 & 2003kj & 2003-11-22.03 & VLT & II & 0.074 &&&&& 22.3 & 1800+900\
e025.wdd3\_15 & & 2003-11-19.21 & Clay & Gal & 0.180 &&& &&& 3x1200\
e027.wcc7\_16 & & 2003-11-21.16 & VLT & Unk &&&& && 22.5 & 3x1200\
e029.wbb3\_15 & 2003kl & 2003-11-19.14 & Clay & Ia & 0.335 & 0.33 & -5 & 90O & good & 21.0 & 3x600\
e121.wbb3\_15 & 2003kl & 2003-11-22.11 & Clay & Ia & 0.335 & 0.33 & -1 & 81B & good & 21.0 & 3x1200\
e103.wbb9\_2 & & 2003-11-21.05 & VLT & Unk & 0.871 &&& &&& 1800\
e106.wbb6\_11 & & 2003-11-20.14 & Clay & Unk & 0.321 &&& && 19.4 & 3x1200\
e108.wdd8\_4 & 2003km & 2003-11-20.21 & Clay & Ia && 0.47 & -8 & 90N & good & 21.8 & 3x1200\
e108.wdd8\_4 & 2003km & 2003-11-21.21 & VLT & Ia && 0.47 & -8 & 90N & good & 21.8 & 2x1800\
e118.waa5\_11 & & 2003-11-22.03 & VLT & AGN & 0.556 &&& &&& 2x1200\
e119.wbb1\_7 & & 2003-11-23.19 & VLT & Gal & 0.560 &&& &&& 1800\
e120.waa5\_9 & & 2003-11-22.05 & Clay & Gal & 0.298 &&& &&& 1200\
e132.wcc1\_7 & 2003kn & 2003-11-22.08 & VLT & Ia & 0.244 & 0.24 & -6 & 90N & good & 21.3 & 2x1800\
e133.wcc1\_7 & & 2003-11-22.08 & VLT & Gal & 0.244 &&& &&& 2x1800\
e136.wcc1\_12 & 2003ko & 2003-11-22.13 & VLT & Ia & 0.360 & 0.36 & -11 & 94D & good & 21.7 & 2x1800\
e138.wdd4\_1 & 2003kt & 2003-11-23.10 & VLT & Ia && 0.61 & +5 & 95D & good & 22.8 & 3x1200\
e140.wdd5\_15 & 2003kq & 2003-11-22.29 & VLT & Ia & 0.606 & 0.62 & -8 & 90N & good & 22.6 & 3x1200\
e141.wdd7\_2 & & 2003-11-22.16 & Clay & II & 0.099 &&& &&& 2x1200\
e143.wdd7\_3 & & 2003-11-23.15 & VLT & Unk &&&& &&& 2x1200\
e147.wdd5\_9 & 2003kp & 2003-11-22.18 & VLT & Ia && 0.64 & -7 & 89B & good & 22.1 & 2x1800\
e148.wdd5\_10 & 2003kr & 2003-11-22.23 & VLT & Ia & 0.427 & 0.42 & -7 & 90N & good & 22.0 & 3x1200\
e149.wdd5\_10 & 2003ks & 2003-11-23.28 & VLT & Ia? && 0.51 & +12 & 95bd & good & 22.2 & 3x1200\
e309.waa9\_14 & & 2003-11-23.32 & GMOS & M-star &&&& &&& 3x1200\
e315.wbb9\_3 & 2003ku & 2003-11-24.31 & GMOS & Ia? && 0.79 & +8 & 72E & poor & 22.9 & 3x1200\
e418.wcc2\_8 & & 2003-11-27 & Baade & N.S. &&&& &&&\
e501.waa1\_1 & & 2003-11-28 & Baade & N.S. &&&& &&&\
e504.waa3\_4 & & 2003-11-29.05 & Baade & AGN & 0.674 &&& && 23.2 & 3x1800\
e510.waa1\_13 && 2003-11-29.08 & GMOS & Unk &&&& && 23.0 & 1800\
e528.wcc5\_3 & & 2003-11-28 & Baade & N.S. &&&& && 23.4 &\
e529.wcc5\_3 && 2003-11-29.10 & Clay & Unk &&&&& & 23.8 & 3x1800\
e531.wcc1\_4 & 2003kv & 2003-11-29.14 & Baade & Ia? && 0.78 & -3 & 95E & poor & 23.4 & 3x1800\
f001.wbb7\_1 & 2003lg & 2003-12-19.17 & MMT & Unk &&&& && 22.5 & 3x1800\
f011.wcc7\_12 & 2003lh & 2003-12-21.31 & KI/LRIS & Ia && 0.54 & +4 & 90N & good & 22.7 & 1500\
f017.wbb9\_10 & & 2003-12-20.33 & GMOS & AGN & 0.725 &&& && 22.7 & 3x1200\
f041.wbb6\_8 & 2003le & 2003-12-20.23 & KI/LRIS & Ia && 0.56 & -4 & 94D & good & 22.7 & 2x1200\
f044.wbb8\_8 && 2003-12-21.10 & MMT & Gal & 0.409 &&& &&& 3x1800\
f076.wbb9\_01 & 2003lf & 2003-12-21.29 & KI/LRIS & Ia && 0.41 & +3 & 94ae & good & 22.1 & 900\
f076.wbb9\_1 & 2003lf & 2003-12-21.17 & MMT & Ia && 0.41 & +4 & 95D & good & 22.1 & 3x900\
f095.wcc2\_8 && 2003-12-20.31 & KI/LRIS & Gal & 0.313 &&& && 21.6 & 3x1200\
f096.waa3\_3 & 2003lm & 2003-12-21.28 & KI/LRIS & Ia & 0.408 & 0.41 & -1 & 92A & good & 22.5 & 1500\
f116.wbb1\_7 && 2003-12-20 & KI/LRIS & N.S. &&&& && 21.6 &\
f123.wcc1\_7 && 2003-12-21.34 & KI/LRIS & Gal & 0.526 &&& && 21.6 & 2x1200\
f213.wbb4\_12 & & 2003-12-19.34 & GMOS & Unk &&&& &&& 2x1200\
f216.wdd4\_15 & 2003ll & 2003-12-21.44 & KI/LRIS & Ia & 0.596 & 0.60 & +5 & 95E & good & 21.6 & 1800\
f221.wcc4\_14 & 2003lk & 2003-12-21.36 & KI/LRIS & Ia? & 0.442 & 0.45 & +2 & 94ae & poor & 22.8 & 1500\
f231.waa1\_13 & 2003ln & 2003-12-21.25 & KI/LRIS & Ia && 0.63 & +0 & 81B & good & 22.9 & 1500\
f235.wbb5\_13 & 2003lj & 2003-12-20.27 & KI/LRIS & Ia & 0.417 & 0.42 & +5 & 95D & good & 22.1 & 2x1200\
f244.wdd3\_8 & 2003li & 2003-12-20.42 & KI/LRIS & Ia & 0.544 & 0.54 & -1 & 95E & good & 22.8 & 2x1800\
f301.wdd6\_1 && 2003-12-21.42 & KI/LRIS & Ia? &&0.52&-3 & 86G &poor & 21.6 & 1500\
f304.wdd6\_2 && 2003-12-21.39 & KI/LRIS & Unk &&&& && 21.6 & 1800\
f308.wdd6\_10 && 2003-12-20.37 & KI/LRIS & Ia? && 0.39 & -7 & 94D & poor & 21.6 & 3x1800\
f441.wbb6\_7 && 2003-12-23.25 & GMOS & Unk &&&& &&& 3x1200\

[^1]: IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.

[^2]: These are b008, b010, b013, b020, b022, b023, b027, c003, c012, c015, d086, d093, e029, e108, and f076.
