![Ratio maps involving the PAH7.7 feature and the F1500W synthetic photometry applied to the MRS cubes for ASPECS galaxies. The first row of panels shows the maps of the total PAH7.7 feature to the synthetic F1500W photometry. Ratios above 1 are possible because the wings of the PAH feature extend well beyond the filter (see text for details and Donnan et al. 2026b). The second row of panels is the fraction of PAH7.7 feature within the F1500W filter to the synthetic F1500W photometry. The third row of panels is the same as the second but for the fraction of continuum emission within the F1500W to the synthetic F1500W photometry -- [astro-ph.GA]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/09/PAHSPECS.png?resize=1200%2C718&ssl=1)
[astro-ph.GA] The physical conditions of the interstellar medium (ISM) are thought to differ greatly at high redshifts compared to local galaxies. Polycyclic aromatic hydrocarbons (PAHs) are key ISM constituents, mediating […]
PAHSPECS
Posted inAstrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Status Report
PAHSPECS: Polycyclic Aromatic Hydrocarbon Properties At Cosmic Noon With JWST/MIRI MRS
Context. Cosmic noon (z ~ 1-3) marks the peak of the cosmic star-formation rate density, when dust-obscured star formation dominated galaxy growth. Mid-infrared spectroscopy probes the interstellar medium through PAH […]
![PAH ratio maps for the five PAHSPECS galaxies. We only show pixels that have a > 3σ measurement of the ratio. The left column shows NIRCAM color images using the F090W, F200W, F444W filters (M. J. Rieke et al. 2023). The second column shows the PAH6.2/PAH7.7 ratio. The third column shows the PAH11.3/PAH7.7 ratios. The fourth column shows the PAH3.3/PAH11.3 ratios. The final column shows [ArII]/PAH6.2. -- astro-ph.GA](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/06/PAHSPECS-Spatially-Resolved-PAH.png?resize=1200%2C716&ssl=1)
Posted inAstrochemistry, Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Imaging & Spectroscopy, Status Report
PAHSPECS: Spatially Resolved PAH Spectroscopy At Cosmic Noon With JWST MIRI MRS
We present spatially resolved spectroscopy with JWST/MIRI MRS of a representative sample of normal star-forming galaxies at z∼1.1 as part of the PAHSPECS program.