CEERS

Epoch 2+3 NIRSpec MSA 1D and 2D Spectra

This data release includes CEERS NIRSpec pointings 4, 5, 7, 8, 9 and 10, obtained as prime observations with NIRCam imaging parallels. Each pointing is observed with three medium gratings (G140M/F100LP, G235M/F170LP and G395M/F290LP; R~1000) and the PRISM (R~100). The PRISM observations in pointings 9 and 10 were affected by an MSA short in December and were repeated at new positions in February. These two new PRISM pointings are 11 and 12.

We have reduced these spectra using custom procedures that improve upon the default pipeline, including custom aperture extractions and aperture masking of detector artifacts and other contaminants. We are working on a paper that describes our reduction in detail. Please cite Arrabal Haro et al. (in prep) if you use any of these data products.

To access the full NIRSpec data release directly, visit this link. Alternatively, see below to access the fully reduced 1D and 2D spectra in each pointing and grating. Please see the associated README describing the release.

Summary

• Instrument: NIRSpec
• Mode: Multi-Object Spectroscopy
• Calibration Pipeline Used: jwst v1.8.5
• CRDS Context pmap: 1029
• Target: NIRSpec pointings 4, 5, 7, 8, 9, 10, 11, 12
• Dispersers/Filters: G140M/F100LP, G235M/F170LP and G395M/F290LP (R~1000); PRISM (R~100)
• Readout: NRSIRS2
• Observation specification: 14 groups, 1 integration
• Dithers: 3 shutter slitlet nod pattern

Spectra

MSA yield file — this file lists each source by MSA ID and RA,Dec, and specfies the CEERS pointing and disperser coverage for each source.

• Fully reduced spectra are available here or in the table below.
• Each entry in the table below provides a link to a zipped directory (*.zip) for each disperser containing multiple data products:
  • *_s2d.fits — Rectified 2D spectrum in units of MJy/px
  • *_x1d.fits — Extracted 1D spectra using custom apertures. Wavelength in microns, flux density in Jy
  • *_x1d-masked.fits — Same as *_x1d.fits but with artifacts masked. Wavelength in microns, flux density in Jy
• We also provide 2D and 1D spectra combining all three M gratings. Please see the README for caveats related to these combined spectra.
• Finally, we provide plots showing the 1D and 2D spectra for all sources and dispersers. The plots are included in the grating and prism directories.
• The first row of the table provides a link to a zipped directory containing all data for the pointing. The last row provides links to the tables of custom apertures used for spectral extraction for each source (which are also included in the total zipped file in the first row).
• All data products are described in detail in the README.

Data reduction

We have reduced images through version 1.8.5 of the JWST Calibration Pipeline with custom Python scripts developed to handle additional corrections. All objects are treated as point sources. We use custom revised 1D extraction apertures that are tailored for each individual target. We have also manually masked artifacts (hot pixels, cosmic rays, etc.) in all spectra. See the README for details on our reduction. Please cite Arrabal Haro et al. (in prep) if you use any of these data products.

Epoch 2 NIRCam WFSS

This data release includes CEERS NIRCam grism pointings 5, 7, 8 and 9, obtained as prime observations with MIRI imaging in parallel. Each pointing is observed with the F356W filter, covering ~3.1-4.0µm with R~1600. Each grism observation was accompanied by three direct images with F356W, including two out-of-field images. All LW observations are paired with F115W imaging (the imaging was included in our NIRCam imaging data release DR0.6).

We have processed the WFSS data primarily through custom procedures designed to optimize the modeling and extraction of slitless spectroscopic data (see Pirzkal et al. 2018 for details).

To access the full WFSS data release directly, visit this link. Alternatively, see below to access the fully reduced spectra in each pointing. Please see the associated README describing the release.

Summary

• Instrument: NIRCam
• Mode: Wide Field Slitless Spectroscopy
• Calibration Pipeline Used: jwst v1.10.2 (Stages 1 and 2, custom procedures used for spectral calibration and extraction)
• CRDS Context pmap: 1089
• Target: NIRCam Pointings 5, 7, 8, 9 (as primary with parallel MIRI imaging)
• Filters: F356W
• Readout: SHALLOW4
• Observation specification: 6 groups, 1 integration
• Dithers: 4-point dithers, optimized for NIRCam+MIRI-F1500W

Spectra

• We include here the extracted spectra of all objects brighter than F356W=25 (AB magnitude). Contamination in slitless data is of increasing concern for fainter targets. Extractions of fainter sources will be included in a future release.
• The F356W imaging catalog associated with the spectra is available here, providing source ID number, RA and Dec, and F356W magnitude. It also specifies which CEERS pointing and NIRCam module (A or B) each source is in, and what grism coverage is available
• Fully reduced spectra are available here or in the table below.
• Each entry in the table below provides a link to a zipped directory (*zip) for each grism (Row and Column) containing multiple data products:
  • *_s2d.fits — Extracted 2D spectra
  • *_x1d.fits — Optimally extracted 1D spectra
• We provide plots showing the 1D and 2D spectra for all sources. There are plots showing each grism individually as well as plots showing the combined 1D extracted spectra from each grism when available.
• The first row in the table provides a link to a zipped directory containing all files for that pointing. Note that these zipped files are ~1.2-1.6 GB and unzip to ~14-19 GB.
• All data products are described in detail in the README.

Data reduction

We have reducded images through stages 1 and 2 of the JWST calibrated Pipeline (version v1.10.2). From there, we use custom procedures developed to handle additional corrections and calibrations for slitless observations. Our custom extraction and contamination modeling is based on the SBE method, closely following the process described in Pirzkal et al. (2018).