Star-by-Star Dust Extinction Mapping in Nearby Galaxies, with ACS & Friends. Chris Clark with Claire Murray, Christina Lindberg, Karl Gordon, Petia Merica-Jones, & co

Chris Clark | ACS 4th Wed, 26 Aug 2024 Clark+ (2021,2023) Large Magellanic Cloud Warm dust (Herschel 100 μm) Cold dust (Herschel 250 μm) Hydrogen (HI atomic & CO molecular)

Chris Clark | ACS 4th Wed 26 Aug 2024 HST Resolution Slightly Better Than FIR Murray+ (in prep.); Clark+ (2023) Herschel Far-Infrared 100, 160, 250 μm From NASA press release that came out on Monday!

Chris Clark | ACS 4th Wed 26 Aug 2024 HST vs Herschel Resolution in the SMC Murray+ (in prep.); Clark+ (2023) 36 arcsec Herschel resolution at 500 μm

Chris Clark | ACS 4th Wed, 26 Aug 2024 BEAST Star-by-Star Extinction Mapping Clark+ (in prep.); Gordon+ (2016) Individual stars in some nearby galaxy BEAST Gordon+ (2016) Bayesian Extinction And Stellar Tool Open source on GitHub: Wavelength (μm) Stellar Emission Observed Flux Dust Extinction

Chris Clark | ACS 4th Wed, 26 Aug 2024 Multiwavelength Coverage is Crucial Clark+ (in prep.); Gordon+ (2016)

Chris Clark | ACS 4th Wed, 26 Aug 2024 Multiwavelength Coverage is Crucial Clark+ (in prep.); Gordon+ (2016)

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024); Delcanton+ (2015)

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) ); Delcanton+ (2015 Only 178 OB (ie, massive) stars identified via spectra in this field

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) Over 42 000 massive stars found with the BEAST (M★ > 8 M☉ ) 100% of the 178 spectroscopically-identified massive stars successfully extracted

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) Over 42 000 massive stars found with the BEAST (M★ > 8 M☉ ) 100% of the 178 spectroscopically-identified massive stars successfully extracted! Massive stars in the rings Massive stars between the rings

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) Kernel Density Estimator (KDE) applied to provide smooth measurement of stellar density

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) ); Delcanton+ (2015 Previous best-resolution dust map of M31: resolution of 25 pc From measuring dust reddening of the red giant brand in the CMD

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) Results from 25 pc dust map suggested that massive stars in areas with lower stellar density (ie, outside rings/arms) exhibit more extinction

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) Results from 25 pc dust map suggested that massive stars in areas with lower stellar density (ie, outside rings/arms) exhibit more extinction Theory says this is what we expect if most massive stars outside the rings are runaways

Chris Clark | ACS 4th Wed 26 Aug 2024 Birth Environments of Massive Stars Lindberg+ (2024) Massive stars seem to experience the same extinction (on average) regardless of location Suggests that massive stars in areas of low stellar density (ie, outside rings/arms), were born there

Chris Clark | ACS 4th Wed 26 Aug 2024 How to Make Hi-Res BEAST Dust Maps? Lindberg+ (in prep.); Murray+ (2024) Example Scylla field in the LMC Scylla PI: Claire Murray

Chris Clark | ACS 4th Wed 26 Aug 2024 How to Make Hi-Res BEAST Dust Maps? Lindberg+ (in prep.); Murray+ (2024)

Chris Clark | ACS 4th Wed 26 Aug 2024 How to Make Hi-Res BEAST Dust Maps? Lindberg+ (in prep.); Murray+ (2024)

Chris Clark | ACS 4th Wed 26 Aug 2024 How to Make Hi-Res BEAST Dust Maps? Lindberg+ (in prep.); Murray+ (2024) We want to turn a large number of individual point measurements of dust extinction into a map of the underlying dust structure. Can do this using Gaussian Process Regression!

Chris Clark | ACS 4th Wed 26 Aug 2024 How to Make Hi-Res BEAST Dust Maps? Lindberg+ (in prep.); Murray+ (2024) We want to turn a large number of individual point measurements of dust extinction into a map of the underlying dust structure. Can do this using Gaussian Process Regression! Herschel PSF at 500 μm (15 pc in LMC)

Chris Clark | ACS 4th Wed, 26 Aug 2024 Clark+ (in prep.); McQuinn+ (2013,2015); Skillman+ (2013); Evans+ (2019) Leo P ACS F475W ACS F814W WFC3 F110W ISM metallicity 0.03 Z⊙ Distance 1.62 Mpc Stellar mass 105.7 M⊙ HI mass 105.9 M⊙

Chris Clark | ACS 4th Wed, 26 Aug 2024 BEAST’ing Leo P Clark+ (in prep.)

Chris Clark | ACS 4th Wed, 26 Aug 2024 BEAST’ing Leo P Clark+ (in prep.) ACS/WFC F475W VLA 21cm HI BEAST fitting finds 40 stars in Leo P with >5-sigma detections of dust extinction

Chris Clark | ACS 4th Wed, 26 Aug 2024 BEAST’ing Leo P Clark+ (in prep.) BEAST fitting identifies two new >8 M☉ OB-stars in Leo P – both exhibit detectable extinction ACS/WFC F475W VLA 21cm HI

Chris Clark | ACS 4th Wed, 26 Aug 2024 BEASTING the BADGRs Clark+ (in prep.); Clark+ (2015,2018); Nersesian+ (2019) Star-by-star extinction mapping in these BADGRs will let us: • Probe the dust geometry at high resolution; is it clumpy? • See if dust is just far away from UV radiation sources • Measure the dust’s intrinsic emissivity, by comparing extinction to far-IR emission • Check for CO freeze-out, by comparing extinction to ALMA data • Use extinction as tracer of total gas column, and search for dark gas by comparing to HI and CO columns NGC 7793 NGC 4449

Chris Clark | ACS 4th Wed, 26 Aug 2024 science.nasa.gov/centers-and-facilities/goddard/hubble-captures-unique-ultraviolet-view-of-a-spectacular-star-cluster/

Chris Clark | ACS 4th Wed, 26 Aug 2024 BEAST’ing Leo P Clark+ (in prep.)