James Webb Space Telescope Feed Post

Discovery of 7 Transients (z_host = 0.6461 - 4.89) in the JADES GOODS-S JWST/NIRCam Images from Cycle 2 Program 3215

Abstract: We report the discovery of 7 supernova sources likely at redshifts z = 0.6461-4.89 down to ~29.5 AB mag, each discovered in the GOODS-South (GOODS-S) field using JWST/NIRCam imaging data obtained by the JWST Advanced Deep Extragalactic Survey (JADES). These supernovae appear as point sources in the F182M, F210M, and F335M NIRCam images taken on UT 2023 October 17 as part of Cycle 2 GO program 3215 (PI: Eisenstein) but are not seen in the F200W or F335M NIRCam images taken on UT 2022 October 20-24 as part of Cycle 1 observation program 1210 (Eisenstein et al. 2023), which covered the same portion of the sky as program 3215. The JWST Advanced Deep Extragalactic Survey (JADES) obtained Cycle-1 NIRCam images of the GOODS-S field using 4 short-wavelength (SW) filters (F090W, F115W, F150W, and F200W) and 5 long-wavelength (LW) filters (F277W, F335M, F356W, F410M, and F444W) as part of program 1210 (Eisenstein et al. 2023, arXiv:2310.12340). The data were taken on UT 2022 October 20-24. The same portion of the GOODS-S field was re-observed on UT 2023 October 17 with NIRCam filters F162M, F182M, F210M, F250M, F300M, and F335M as part of Cycle 2 program 3215 (first epoch). Difference images could be directly created by subtracting the F335M images, and additional difference images were created by subtracting the program 1210 F200W image from the averaged 3215 F182M and F210M images. This worked because the combined transmission curves of F182M and F210M matched the F200W transmission curve very well, although caution was exercised to differentiate emission lines from real transients in the difference images. Seven supernovae were detected in these difference images. Below we list the position, photometry and likely host galaxy redshift for each of these sources. The information on the likely host galaxies was obtained either from SED modeling using the code EAZY (Brammer et al. 2008) or from publicly available catalogs, and all the reported magnitudes are in AB. The JADES collaboration has provided an interactive FITSMap (https://jades.idies.jhu.edu/public/) that allows users to interact with the NIRCam-detected galaxies in the GOODS-S field, which covers the 3215/1210 footprint. This resource can be used to view the reported likely host galaxies. 2023vnz (jades-gs-3215d) lies in the galaxy JADES-GS+53.07798-27.85824 (z_spec = 0.6461 from Balestra et al. 2010, A&A, 512, 12). It was discovered at position (03:32:18.7891, -27:51:30.699) (J2000) and has the following preliminary apparent magnitudes measured from the difference images: (F182M+F210M)/2-(F200W) = 26.58 ± 0.02, F335M = 27.53 ± 0.04. The corresponding absolute magnitudes are -15.81 at 1214 nm and -14.87 at 2035 nm.