Release Data

HSC PDR1 includes over 100 square degrees of deep multi-band data.  See the figures below for the survey footprints.  The blue, green, and red areas show the Wide, Deep, and UltraDeep layers, respectively.

The table on the right gives a quick overview of the quality of our data.  The depths are given as 5 sigma limiting magnitudes for point sources.  Our target exposures and depths are also shown for reference for each layer.

In addition to the SSP data, merged COSMOS stacks using data from the SSP team and the University of Hawaii are available (see below).

Data Retrieval

The data can be retrieved in multiple ways.  The simplest way to retrieve catalog data is to use the database.  We have online/offline SQL tools.  For image data, most users will find hscMap, an online image browser, very useful.  For binary files, we have a data search tool as well as image cutout tool.  All these tools are summarized in the Data Access page.  In order to access the data, you first have to sign up for an account.  Before you use our data products, we strongly recommend you to go over the data release paper and this page.  If you use the HSC data in your publication, please acknowledge us.  This site delivers only the processed data.  Raw data can be retrieved from SMOKA.

Data Quality

We have performed a number of validation tests for our data products.  Details are described in the data release paper, but a complete set of the plots for some of the most important tests can be found here.

Known Problems

Although our data are of high quality, there are several known problems.  We have a dedicated page to summarize them.  Please check out the page before you use our data for your science.

Pipeline Data Products

While all the image files are available for direct download, some of the catalog fits files are not available.  Unavailable products are marked in light gray in the right panel.

ICSRC Catalog of bright sources detected and measured on a CCD, and used in astrometric and photometric calibration. (FITS BINTABLE)

MATCH: Bright source catalog combined with external reference (PS1) sources by cross-matching between detected sources and PS1 catalog sources. The identification numbers and separation angles in cross-matching are recorded for the external sources. (FITS BINTABLE)

ML: Another form of cross-matched bright source catalog (MATCH), in which coordinates and fluxes of the external sources are explicitly listed (de-normalized) rather than listing the identification numbers only. (FITS BINTABLE)

SRC: Catalog of sources detected and measured on a CCD, output from the final stage of the single frame processing. See CALSRC, too. (FITS BINTABLE)

SRCMATCH:  Source catalog (SRC) cross-matched with the external reference (PS1) sources. (FITS BINTABLE)

SRCML: Another form of SRCMATCH, in which coordinates and fluxes of the external sources are explicitly listed. (FITS BINTABLE)

CORR: Corrected CCD image, or resultant processed sky-subtracted image with calibrated coordinates and magnitude zeropoint from the single frame processing. See CALEXP, too. (Muliti-extension FITS IMAGE + BINTABLE)

BKGD: Sky background pattern subtracted from the image. (Multi-extension FITS IMAGE)

fcr:  Contains flux scale and its positional variation of a CCD determined by mosaicing. (Multi-extension FITS)

wcs: The world coordinate system of a CCD determined by mosaicing. (Multi-extension FITS)

CALEXP: Corrected image (CORR) with the flux and WCS corrections applied. (Muliti-extension FITS IMAGE + BINTABLE)

CALSRC Source catalog (SRC) with the flux and WCS corrections applied. (FITS BINTABLE)

det: List of source positions and footprints detected on a coadd patch. (FITS BINTABLE)

warp: Image of a single visit (CORR) transformed onto a destination tangential plane in a tract. (Multi-extension FITS IMAGE + BINTABLE)

calexp: Coadd image in a single band, or resultant image from the Stack stage, which combines all the overlapped warp images. (Multi-extension FITS IMAGE + BINTABLE)

mergeDet: List of source positions and footprints containing all sources detected in any bands in a coadd patch. (FITS BINTABLE)

meas: Single-band source catalog measured on each of sources in a coadd image listed in mergeDet. Peak positions and shapes of sources are determined in a band being measured. (FITS BINTABLE)

measMatch: Single-band source catalog (meas) cross-matched with the external reference (PS1) sources. (FITS BINTABLE)

measMatchFull: Another form of measMatch.  Coordinates and fluxes of the external sources are explicitly listed in the same manner as in ML (FITS BINTABLE).

ref: List of source positions and shapes determined by merging results of the single-band measurements (meas) in a coadd. Reference catalog used for the final forced measurement.

forced_src: Single-band source catalog generated by a forced-mode measurement, which is performed on each of sources listed in the ref catalog. Positions and shapes are held fixed in the reference band in the measurements. Final catalog from the forced photometry.

ab:  Catalog of sources generated by a post-processing run, which includes PSF-convolved aperture fluxes and some additional information.  See the Processing page for details.

Value-added Catalogs

In addition to the pipeline products, we also provide photometric redshifts, a collection of public spectroscopic redshifts, random points, and the bright star masks in our database.

The HSC photo-z working group computes photo-z’s for a large fraction of the objects in the release using several independent codes. Catalog products such as photo-z point estimates and confidence intervals are available from the database and full probability distributions are available in the FITS format for download. Refer to Tanaka et al. 2017 for details.

Objects around bright stars likely have bad photometry and these objects are flagged during the processing.  Although this is a useful database flag, there are a few known problems.  Refer to the Known Problem page details.

The Deep and UltraDeep fields are observed in a few narrow-bands in addition to the broad-band filters.  These narrow-band filters allow us to detect emission line objects at some specific redshifts and the emission-line object catalog from Hayashi et al. 2017 is now publicly available.

A deep, multi-band photometric catalog is constructed by joint efforts of HSC and SPLASH teams.  Refer to Mehta et al. for details of the catalog.

Partly for the purpose of the photo-z calibrations, we have collected public spectroscopic redshifts from the literature and the collection is matched to the HSC objects by position.  Each survey has its own flagging scheme to indicate the redshift confidence and we have a homogenized flag for each object for easy selection of objects with reliable redshifts. It is important to emphasize that users should acknowledge the original data source(s) when using this table.

For clustering analysis, a set of random points across the survey area will be useful.  Such a collection of random points can be found in the database.

The HSC weak-lensing team has carried out a set of detailed image simulations to characterize and calibrate the shape measurements from the HSC imaging data.  Data used for the simulations are available for the public users.

COSMOS stacks

The COSMOS field is one of the key extragalactic fields and is a valuable calibration field.  We have generated various COSMOS stacks and make them available for the community to fully exploit this unique field.

Using subsample of the UltraDeep COSMOS data, we have generated three sets of Wide-depth stacks with 0.5, 0.7 and 1.0 arcsec seeing in all the bands.

The SSP team and the University of Hawaii have joined forced to produce very deep optical images of the COSMOS field by combining data from both teams.

Tracts and Patches

The figures below are blow-ups of the coverage in each field for each filter.  The large squares are tracts (approx. 1.5deg wide) and each tract is broken into 9×9 patches, each of which is 4200 pixels on a side.  There is an overlap of 1 arcmin between the two adjacent tracts.  Patches have an overlap of 100 pixels (~16.8 arcsec).

Ultra-Deep

UD-COSMOS
UD-SXDS

Deep

D-COSMOS
D-DEEP2-3
D-ELAIS-N1
D-XMM-LSS

Wide

Because only the full-color full-depth area is included in this release.  The area covered in all the filters are nearly identical, except for VVDS, in which a whole tract in the y-band is missing due to a processing failure.

Wide-XMM (RA = 25-45 deg)
Wide-GAMA09H (RA = 125-150 deg)
Wide-WIDE12H (RA = 165-195 deg)
Wide-GAMA15H (RA = 205-230 deg)
Wide-HECTOMAP (RA = 225-255 deg)
Wide-VVDS (RA = 330-350 deg)
AEGIS (RA = 215 deg)

The files below give the exact celestial coordinates of each tract and patch.

List of missing patches

Our data processing failed for a small number of patches, resulting in holes in the survey footprint.  Here is a list of missing patches.

Color Terms

Information of the color terms for conversion HSC to PS1 filter system. Please use carefully, since the evaluation is under way.

The color terms are calculated by using value in the table, for example,
g_hsc = 0.00730066 + 0.06508481 * (g-r)_ps1 – 0.01510570 * (g-r)_ps12

HSC PS1 a0 a1 a2
HSC-G  (g) g-r 0.00730066 0.06508481 -0.01510570
HSC-R  (r) r-i 0.00279757 0.02093734 -0.01877566
HSC-R2 (r2) r-i 0.00117690 0.00003996 -0.01667794
HSC-I  (i) i-z 0.00166891 -0.13944659 -0.03034094
HSC-I2 (i2) i-z 0.00180361 -0.18483562 -0.02675511
HSC-Z  (z) z-y -0.00907517 -0.28840221 -0.00316369
HSC-Y  (y) y-z -0.00156858 0.14747401 0.02880125
NB0816 (n816) i-z 0.01191062 -0.68757034 -0.10781564
NB0921 (n921) z-y 0.00142051 -0.59278367 -0.25059679
The model colors for fitting are calculated from the atlas of Gunn & Stryker (1983) spectral library and the filter response functions of each system. Stars having g -r < 3.0 are used for calculation.