Mission Overview
The NIRSpec WIDE GTO Survey ("WIDE")
Primary Investigator: Michael Maseda
HLSP Authors: Michael Maseda, Anna de Graaff, Stefano Carniani, Eleonora Parlanti
Released: 2024-09-09
Updated: 2024-09-09
Primary Reference(s): Maseda et al. 2024
DOI: 10.17909/57km-j134
Citations: View ADS Metrics
Source Data:
Overview
Here the team releases the reduced 2D and 1D extracted spectra. To mitigate self-subtraction when performing nodded background subtraction for very extended objects, the team releases the PRISM data with a two-point nodding pattern in addition to the default three-point pattern; only two-point nodding is available for the high-resolution gratings. Various 1D boxcar extraction apertures are released, which can be chosen to optimize a source’s signal-to-noise ratio. In total the team produces three-nod, 3 pixel extraction and three-nod 5 pixel extraction for the PRISM exposures and two-nod 5 pixel extraction and two-nod 15 pixel extraction for PRISM, G235H, and G395H exposures.
The current release (September 2024) consists of the data for the five pointings in the CANDELS/AEGIS field (pointings 2017-2021). Future releases will contain data from the other Wide pointings.
Data Products
Both 1D and 2D extracted spectra are available.
1D spectra are available for each grating/filter combination according to the following convention:
hlsp_wide_jwst_nirspec_<field>-<pointing><ID>_<filter>-<grating>_v1.0_<nnod>-spec1d.fits
where:
- <field> is the name of the CANDELS field, e.g. “aegis”
- <pointing> is the pointing number, e.g. “2021” (see Maseda et al. 2024 for a list of the 31 pointings)
- <ID> is the ID number for a particular object in that pointing
- <filter> and <grating> are the specified observing setup, namely “clear/prism,” “f170lp/g235h,” and “f290lp/g395h”
- <nnod> is the nodding pattern used in the reduction, “2nod” is available for all exposures and “3nod” is only available for the PRISM exposures
2D spectra follow the same convention, but have the extension “spec2d.fits”
Data file types:
| -spec1d.fits | 1D spectra files |
| -spec2d.fits | 2D spectra files |
Within the 1D files, there are extensions corresponding to the number of pixels used in the extraction (3, 5, or 15). Each of these extensions consists of a table with “WAVELENGTH,” “FLUX,” and “FLUX_ERR” values: wavelengths are in microns, fluxes and errors are in units of erg/s/cm2/Angstrom.
The 2D files have extensions “FLUX,” “FLUX_ERR,” “WAVELENGTH,” “RA,” and “DEC.” These are 2D arrays with the same units as the 1D data products.
Data Access
MAST Portal and Astroquery
All observations are available in the MAST Portal and astroquery. Set the 'Provenance Name' filter to WIDE in the Portal Advanced Search to match all observations. The spectra can be downloaded for each target as a bundle or individually retrieved by selecting the download basket. The observations can also be retrieved programmatically using the astroquery.mast module. The code example below retrieves all products.
from astroquery.mast import Observations
all_obs = Observations.query_criteria(provenance_name="wide")
data_products = Observations.get_product_list(all_obs)
Observations.download_products(data_products)
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A web-based interface for cross-mission searches of data at MAST or the Virtual Observatory.
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Search for and download WIDE data products programmatically in Python.
Direct Download Links
The data products can also be downloaded directly using the cURL script linked below:
| cURL Script for All WIDE Spectra | |||
|---|---|---|---|