2022年12月18日 · Using PHANGS-JWST and PHANGS-MUSE observations, we investigate how the PAH fraction changes in about 1500 HII regions across four nearby star-forming galaxies (NGC 628, NGC 1365, NGC 7496, IC 5332). We find a strong anti-correlation between the PAH fraction and the ionization parameter (the ratio between the ionizing photon flux and the ...

2024年1月8日 · We analyze the PAH features observed at 3.3, 7.7, and 11.3 {\mu}m using F335M, F770W, and F1130W images obtained from JWST. Additionally, we utilize UVIT images to assess the star formation associated with these PAH emitting regions.

2023年2月16日 · In this study leveraging new JWST observations for four star-forming galaxies, we have demonstrated that hydrogen-ionizing UV radiation is the dominant mechanism for PAH destruction in H ii regions. This work is based on observations …

2023年2月16日 · We present maps of the 3.3 μm polycyclic aromatic hydrocarbon (PAH) emission feature in NGC 628, NGC 1365, and NGC 7496 as observed with the Near-Infrared Camera imager on JWST from the PHANGS–JWST Cycle 1 Treasury project.

2024年1月2日 · JWST enables us to detect faint IR galaxies that have prominent polycyclic aromatic hydrocarbon (PAH) features in the mid-IR wavelengths. PAH is a valuable tracer of star formation and dust properties in the mid-infrared wavelength.

Polycyclic aromatic hydrocarbons (PAHs) play a critical role in the reprocessing of stellar radiation and balancing the heating and cooling processes in the interstellar medium but appear to be destroyed in H II regions. However, the mechanisms driving their destruction are still not completely understood.

A first look is taken at the NIRSpec 1–5μm observations from James Webb Space Telescope program 1591 that targets seven objects along the low-mass stellar life cycle with polycyclic aromatic hydrocarbon (PAH) emission. Spectra extracted from a 1 5 radius circular aperture are explored, showing a wealth of features, including the

2025年3月23日 · JWST observations, when combined with HST data, promise to improve age estimates of star clusters in nearby spiral galaxies. However, feedback from young cluster stars pushes out the natal gas and dust, making cluster formation and evolution a challenge to model. Here, we use JWST + HST observations of the nearby spiral galaxy NGC 628 to produce spectral energy distribution (SED) templates of ...

JWST observations of polycyclic aromatic hydrocarbon (PAH) emission provide some of the deepest and highest resolution views of the cold interstellar medium (ISM) in nearby galaxies.

2023年2月16日 · In this Letter, we present a test case for using PAH emission observed with JWST-MIRI as a high-resolution, high-sensitivity, cold ISM phase-agnostic tracer of gas. We use scalings determined in H 2-dominated (as traced by CO) but diffuse-ISRF-heated gas, and apply those to the faint PAH emission in the F1130W map.