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Mission Overview

Scylla

 

Primary Investigator: Claire E. Murray

HLSP Authors: Petia Yanchulova Merica-Jones, Christina W. Lindberg, Claire E. Murray, Benjamin F. Williams

Released: 2024-10-16

Updated: 2024-10-16

Primary Reference(s): Murray et al. 2024

DOI: 10.17909/mk54-kg51

Citations: See ADS Statistics

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Source Data:

 

Scylla Figures

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The Scylla Logo

This figure shows the Scylla project logo, which consists of six different-colored monster heads around a circular grayscale image of stars and dust or gas clouds.

The Scylla logo, depicting six “heads” of the mythical monster Scylla in colors to represent the multi-wavelength coverage of the imaging survey.

Scylla's View of the SMC

This figure has one large panel and two smaller panels to the right. The large panel has a grayscale map of the SMC, which appears as dark, wispy clouds against the white background. There are dots of different colors around the map, each labeled with a number. Two red boxes highlight regions in the map, which are expanded in the panels to the right. The two panels to the right show zoomed-in views of dense, dusty regions of the SMC, which also appear as wispy, but denser, dark clouds. These panels also have several colored dots with numbered labels.

Maps of the peak brightness temperature of 21cm emission in the SMC (Pingel et al. 2022) with observed Scylla SMC fields. In each panel, regions where fields overlap are identified by dashed red bounding boxes and expanded at right. There are 96 fields as part of the release described in this paper (48 in the SMC). The number of filters used to observe each field is illustrated by the number of concentric circles overlaid at each position. Each field is tagged by its “short" name number (see Murray et al. 2024). In the expanded panels, the size of each footprint is plotted in white outline.

Scylla's View of the LMC

This figure has one large panel and one smaller panel to the right. The large panel has a grayscale map of the LMC, which appears as dark, wispy clouds against the white background. There are dots of different colors around the map, each labeled with a number. A red box highlights a region in the map, which is expanded in the panel to the right. The right panel shows a zoomed-in view of a dense, dusty region of the LMC, which also appears as wispy, but denser, dark cloud. This panel also has several colored dots with numbered labels.

Maps of the peak brightness temperature of 21cm emission in the LMC (Kim et al. 1999) with observed Scylla LMC fields. In each panel, regions where fields overlap are identified by dashed red bounding boxes and expanded at right. There are 96 fields as part of the release described in this paper (48 in the LMC). The number of filters used to observe each field is illustrated by the number of concentric circles overlaid at each position. Each field is tagged by its “short" name number (see Murray et al. 2024). In the expanded panels, the size of each footprint is plotted in white outline.

Overview

Named after the multi-headed monster from the myth of Ulysses, Scylla is a Hubble Space Telescope (HST) survey of the stellar populations, interstellar medium and star formation in the LMC and SMC. As a pure-parallel complement to the spectroscopic Ultraviolet (UV) Legacy Library of Young Stars as Essential Standards (ULLYSES) survey, Scylla surveyed fields parallel to ULLYSES targets with maximum photometric coverage from the near UV to the near-infrared (IR) with Wide Field Camera 3 (WFC3).

All fields have been imaged in at least two filters - F475W and F814W. 64% of fields have been imaged in at least three and as many as seven WFC3 filters spanning the UV to IR. On average, Scylla reaches 50% completeness at mF225W = 26.0, mF275W = 26.2, mF336W = 26.9, mF475W = 27.8, mF814W = 25.5, mF110W = 24.7, and mF160W = 24.0 Vega magnitudes in its photometric catalogs, which is faintward of the ancient main sequence turnoff in all filters. Here the team provides images and photometric catalogs from the survey. These represent the widest-area coverage of the MCs with HST photometry to date.

The primary Scylla science goals are to:

  • resolve how dust properties vary with interstellar environment
  • constrain the multi-dimensional structure of the ISM of the MCs
  • probe the detailed star formation histories of the MCs

The first data release consists of 96 fields (48 in the LMC and 48 in the SMC) imaged over 342 orbits. Future releases will include all survey data (roughly 20 additional fields expected).

Data Products

Scylla provides drizzled images, photometric catalogs, and single- and multi-color preview images for each field.

Data file naming convention:

hlsp_scylla_hst_wfc3_<galaxy>-<id>_<filters>_<version>_<type>

where:

  • <galaxy> is the primary galaxy target, either "smc" or "lmc"
  • <id> is the number assigned to the field
  • <filters> is the WFC3 filter used, or "multi" if multiple were used
  • <version> is the version number
  • <type> is the file type

Data file types:

_drz.fits Astronomically-correct drizzled images used for alignment and bookkeeping of star positions by DOLPHOT.
_st.fits Photometric catalog, includes flags for additional quality cuts (see Murray et al. 2024).
_image.png Multi-color image of a field
_preview.png Single-color preview image of a field

Data Access

MAST Portal and Astroquery

All observations are available in the MAST Portal and astroquery. Set the 'Provenance Name' filter to SCYLLA in the Portal Advanced Search to match all observations. The files can be downloaded for each field 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="scylla")
data_products = Observations.get_product_list(all_obs)
Observations.download_products(data_products)

  • MAST Portal

    Link to the MAST Portal Webpage
    A web-based interface for cross-mission searches of data at MAST or the Virtual Observatory.
    Portal

  • MAST Astroquery

    Search for and download Scylla data products programmatically in Python.
    MAST Astroquery

Citations

Please remember to cite the appropriate paper(s) below and the DOI if you use these data in a published work. 

Note: These HLSP data products are licensed for use under CC BY 4.0.

References

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  • Murray et al. 2024

    Scylla I: A pure-parallel, multi-wavelength imaging survey of the ULLYSES fields in the LMC and SMC