- This event has passed.
Speaker: Brenda Frye (University of Arizona) – Title: Measuring the Hubble-Lemaitre Constant with James Webb Space Telescope Observations of the Lensed Supernova H0pe
June 13 @ 4:00 pm - 5:00 pm
Research Progress Meeting
Date: June 13, 2024
Time: 4:00- 5:00 pm
Location: Sessler Conference Room- 50A-5132 [In-Person and HYBRID]
Speaker: Brenda Frye (University of Arizona)
Title: Measuring the Hubble-Lemaitre Constant with James Webb Space Telescope Observations of the Lensed Supernova H0pe
Abstract: A review of cluster lensing in the first two years of James Webb Space Telescope (JWST) observations is presented, focussing on the JWST Guaranteed Time Observations (GTO) program the Prime Extragalactic Areas for Reionization and Lensing Science (PEARLS). These observations range from the spectacle of JWST “first light” images of the distant universe to dense galaxy cluster fields that uncovered unprecedented numbers of giant arcs and image multiplicities. A point-source was discovered in the PEARLS image of the galaxy cluster field PLCK G165.7+67.0 (G165) that is bright and appears in three different locations as a result of strong lensing. Additional JWST observations confirmed this source to be a normal Type Ia supernova (SN) at a redshift of 1.783 that we call “SN H0pe,” making it one of the highest redshift standard candles. In a blinded approach, seven independent lens models were constructed, and time delays between the images were measured in two ways, off of: (1) the light curve, and (2) model fits to the spectra of each of the three SN images. During the unblinding event, a value for H0 was inferred by rescaling the lens-model predicted time delays to match the measured time delays. This is only the second measurement of H0 by the method of a multiply-imaged supernova, and the first by a standard candle. G165 has one of the highest rates of star formation summed up over the background lensed sources, making continued monitoring potentially rewarding for the discovery of additional SNe.
Join Zoom Meeting
https://lbnl.zoom.us/j/98854322464?pwd=K2tKUm1VZjRlV1J5RHE3cXdHQzRxdz09
Meeting ID: 988 5432 2464
Passcode: 142239