JWST ERS Program TEMPLATES

TEMPLATES: Targeting Extremely Magnified Panchromatic Lensed Arcs and their Extended Star formation

TEMPLATES: Targeting Extremely Magnified Panchromatic Lensed Arcs and their Extended Star formation

TEMPLATES is an approved 58-hour JWST Early Release Science (ERS) program to study star formation in four gravitationally lensed galaxies at redshifts of 1 to 4.

Abstract

We propose high signal-to-noise NIRSpec and MIRI IFU spectroscopy, with accompanying imaging, for 4 gravitationally lensed galaxies at 1<z<4. This program will spatially resolve the star formation in galaxies across the peak of cosmic star formation, in an extinction-robust manner. Lensing magnification pushes JWST to the highest spatial resolutions possible at these redshifts, to map the key spectral diagnostics of star formation and dust extinction: H-alpha, Pa-alpha, and 3.3um PAH within individual distant galaxies. Our targets are among the brightest, best-characterized lensed systems known, and span a wide range of specific star formation rate, extinction, and luminosity. They have extensive ancillary datasets. Our science goals are: 1) demonstrate extinction-robust star formation rate diagnostics for distant galaxies; 2) determine the physical scales of star formation in distant galaxies, in an extinction-robust way; 3) measure specific star formation rates and compare the spatial distribution of the young and old stars; and 4) measure the physical conditions of star formation and their spatial variation.

This program uses key instrument modes, heavily exercising the NIRSpec and MIRI IFUs. The resulting science-enabling data products will demonstrate JWST’s capabilities and provide the extragalactic science community with rich datasets. In four deliveries, we will provide high-quality Level 3 data cubes and mosaics, empirical star formation diagnostics, maps of star formation, extinction, and physical properties, a tool for comparing NIRSpec and MIRI data cubes, and cookbooks on data reduction, analysis, and calibration strategy.

Community briefings

Webinar (23 min), from March 2020, where we describe our program

Advice on whether leak-cals and dedicated backgrounds should be taken for NIRSpec IFU mode (PDF, 1/20/2023)

Science Goals

  1. Demonstrate extinction-robust star formation rate diagnostics for distant galaxies;

  2. Determine the physical scales of star formation in distant galaxies, in an extinction-robust way;

  3. Measure specific star formation rates and compare the spatial distribution of the young and old stars; and

  4. Measure the physical conditions of star formation and their spatial variation.

Technical goals

  1. Shake out the JWST spectroscopic pipeline. We will reduce the raw data from the TEMPLATES ERS program using the JWST pipeline, which is open-source python. In doing so, we will optimize each step, determine parameter settings, and adding additional steps and algorithms as required. We will share these best practices via Cookbooks (see #technical goal 4) and github pull requests.

  2. Test the JWST imaging pipeline. We will also determine parameter settings and additional steps for the imaging pipelines for NIRCam and MIRI.

  3. Establish IFU best practices. We will determine whether off-source background observations are strictly required, or whether the background may be derived from the periphery of on-source frames. We will determine the difference that MSA leak calibrations make. From these experiments, we will recommend best practices for extragalactic spectroscopy, to guide Cycle 2 proposers. Any streamlining of IFU observations would make a big difference for observatory efficiency.

  4. Cookbooks and community project updates. We will write tutorial-style cookbooks, complete with example data and code, that users can follow step-by-step for the ERS TEMPLATES data,that can be applied to other datasets. We are publishing these as Jupyter python notebooks. We will explain these cookbooks, and our recommended best practices, in ERS webinar briefings and community workshops.

  5. Additional science-enabling data products. We will produce not only level 3 data products, but also source plane maps of physical quantities like star formation rate and extinction.

Deliverables

Deliverables are now on MAST!

Delivery 1: pre-launch. Existing lens models; high-level HST and ALMA data. Delivered.

Delivery 1a: pre-launch. Simulated raw and science-ready JWST data; pipeline cookbook; improved lens models.

Delivery 2: L+10m. Level 3 data products and cookbooks; plot of SNR versus surface brightness for IFUs

Delivery 3: L+13m. High-level science products: maps of H alpha, emission line ratios, extinction, source-plane reconstructions, SED fits

Delivery 4: L+19m. Clean-up delivery of improved data products