Mission Overview
Search For The Brightest of Reionizing Galaxies ("SuperBoRG")
Primary Investigator: Takahiro Morishita
HLSP Authors: Takahiro Morishita
Released: 2021-05-05
Updated: 2022-06-13
Primary Reference(s): Morishita 2021
Citations: See ADS Statistics
(Top) Distribution of SuperBoRG fields (red circles) in ecliptic coordinates, overlaid on a temperature map from the WMAP 5-year data (Hinshaw et al. 2009). Most of the fields were selected from high Galactic latitudes (|b| > 30 deg), to avoid fields with significant Galactic extinction and/or dominated by foreground stars. (Bottom Left): Effective area and 5-sigma limiting magnitude of various extragalactic survey programs of HST. Survey programs included in SuperBoRG (red square) are shown with cross symbols; BoRG Cycles 17, 19, 22, 25 (orange), HIPPIES Cycles 17, 18 (blue), CLASH, RELICS, and COS-GTO (green). Legacy surveys such as CANDELS, including its extended version presented in Bouwens et al. (2019, CANDELS-B19), and HUDF09, HUDF12, and XDF programs are shown with gray squares. (Bottom Right): Histogram of limiting magnitude of the SuperBoRG fields. Survey programs are distinguished by the same color scheme as in the left panel.
Overview
SuperBoRG is an archival project that primarily aims to search for luminous galaxies and quasars at redshifts z > 7. SuperBoRG compiled HST’s multi-band imaging data previously taken in parallel observations designed for extragalactic science and reduced all data in a consistent manner. From both pure-parallel and coordinated-parallels programs with WFC3 in the past decade, it collected 316 independent sightlines with multi-band imaging data at moderate depth. The total area reaches ~0.41 deg^2, making it one of the largest area, extragalactic datasets. All data were reduced with a new pipeline with a few updates from the previous BoRG HLSP data release, including sophisticated sky subtraction and PSF matching. This data release includes imaging data and catalogs.
Release 1.1
This release adds a new catalog that lists limiting magnitudes of all fields.
This release also reflects minor updates to some of the Release 1.0 products, including:
- Fix to mismatched source numbers in the catalogs.
- Fix to imaging data in the 0116+1425 field, to achieve the full depth.
Release 2.0
This release includes a set of photometric catalogs that are based on the F125W detection. This was done particularly for z~8 galaxies, where the Lyman break remains blueward of the F125W band, and thus an F125W image can be better suited for source detections. The team also found that the F125W filter generally affords higher signal-to-noise ratios than the F160W filter for the same exposure time of flat spectral energy distribution in Fν. For these reasons, and to remain as complete as possible, the team re-ran their photometry pipeline based on the F125W detection, in the exact same manner as for the previous v1.0 release with the F140W+F160W images.
This release adds a new catalog that lists limiting magnitudes of all fields, for advanced photometric analyses by users.
This release also reflects minor updates to some of the version 1 products, including:
- fix to mismatched source numbers in the catalogs.
- fix to imaging data in four fields (1031+3804,1358+4334,1424+2411,1503+0352), to improve image alignment.
- fix to imaging data in the 0116+1425 field, to improve the image depth.
- removal of F140W files from 1031+3804, because that filter had a guide star issue and the data was of poor quality. The files removed were: hlsp_superborg_hst_wfc3_borg-1031+3804_f140w_v1_drz-conv-sci.fits, hlsp_superborg_hst_wfc3_borg-1031+3804_f140w_v1_drz-sci.fits, hlsp_superborg_hst_wfc3_borg-1031+3804_f140w_v1_drz-rms.fits, hlsp_superborg_hst_wfc3_borg-1031+3804_f140w_v1_drz-wht.fits
Data Products
The image products have the following file naming convention:
hlsp_superborg_hst_<ins>_borg-<id>_<filter>_<ver>_<ext>
where:
- <ins> = Name of instrument, either "wfc3", "acs", or both ("acs-wfc3").
- <id> = Target ID of the galaxy, e.g., "0006+1607".
- <filter> = Name of filter used, e.g., "f600lp", or set to "det" for the detection image and "opt" for the optical-combined image.
- <ver> = Version number ("v1" or "v2").
- <ext> = Type of image product, described below.
The catalog products have the following naming convention:
hlsp_superborg_hst_acs-wfc3_all_<filter>_<ver>_<ext>
where
- <filter> = One of "f125w" or "f140w-f160w".
- <ver> = Version number ("v1" or "v2").
- <ext> = Type of catalog product, described below.
Note on "detection" and "optical-combined" files.
The "detection" image products make use of the F140W+F160W filters if F140W is available, F160W only if not. They use "det" in the filter part of the file name.
The "optical-combined" image products make use of all of the following filters, depending on which are available: 'F300X', 'F350LP', 'F435W', 'F475W', 'F475W', 'F475X', 'F555W', 'F600LP', 'F606W', 'F625W', 'F775W', 'F814W', 'F850LP'. They use "opt" in the filter part of the file name.
Note on segmentation map headers.
The headers of the segmentation map come from one of the HST images that went into making them, but they are effectively meaningless and should be ignored. The segmentation map files are applicable to the detection images, and thus the individual keywords in the headers of these files should be ignored.
Data file types:
Images
| _drz-sci.fits | Science image at original resolution. Pixel scale is set to 0.08 arcsec. |
| _drz-wht.fits | Weight map. |
| _drz-rms.fits | Root-mean-square map. |
| _seg.fits | Segmentation map, especailly useful for those using the source catalog. |
| _drz-conv-sci.fits | Science image convolved to F160W PSF size. |
Catalogs
| _master.fits | Master catalog for all sources in SuperBoRG. |
| _photometry.fits | Source photometric flux catalog. |
| _redshift.fits | Source redshift catalog. |
| _highz.fits | High-redshift source flag catalog. If a source satisfies a color selection, the value for the corresponding column is set to 1; if not, 0. If the source is not qualified for the color selection, the value is set to -99. |
| _limmag.fits | Limiting magnitudes for all fields. |
Data Access
Bundles of all image products for a given target are available in the table below in .tar.gz file format (each is a few hundred MB in size). The catalog files are provided in FITS format, and range in size from ~50 to ~200 MB. The limiting magnitude catalog is ~350 KB.
| Set | Catalog Files | |||
|---|---|---|---|---|
| F140W-F160W | Master | Photometry | High-Z | Redshift |
| F125W | Master | Photometry | High-Z | |
| Limiting Magnitude | Limmag | |||