University of Connecticut

Events Calendar

MS Dissertation Defense

Thursday, March 18, 2021
1:00pm – 3:00pm

Storrs Campus
Video meeting

Graduate Student Nikko Cleri, Department of Physics, University of Connecticut

Paschen-line Star Formation and Dust Attenuation with HST and JWST

Star formation rates (SFRs) are one of the most critical quantities in understanding galaxy evolution. There exist many different methods of measuring extragalactic SFRs, commonly using emission-line luminosities. Recombination lines of hydrogen are especially useful as SFR tracers due to their insensitivity to nuisance parameters like metallicity, density, and temperature in the interstellar medium. Paschen emission offers a ‘gold standard’ tracer of recent (< 10 Myr) star formation with its relative insensitivity to interstellar dust attenuation compared to more common Balmer and UV continuum SFRs, while maintaining the benefits of hydrogen recombination lines. We use Paschen (1282 nm) observations from the Hubble Space Telescope (HST) G141 grism to study star formation and dust attenuation properties of 32 low redshift (z < 0.3) galaxies in the CANDELS Lyman Emission at Reionization (CLEAR) survey. We find evidence suggesting that Pa is revealing star formation otherwise ‘hidden’ within gas optically thick to shorter wavelengths, and we use Pa/H. We also find evidence to support the claim that lower mass galaxies exhibit burstier star formation histories. We will also discuss future observations of Paschen-line star formation with the James Webb Space Telescope (JWST).

Webex link:


Prof. J. Trump

Physics Department (primary), College of Liberal Arts and Sciences, UConn Master Calendar

Control Panel