_version_ 1866909754787364864
author Matsuura, Mikako
Volk, Kevin
Kavanagh, Patrick
Balick, Bruce
Wesson, Roger
Zijlstra, Albert A.
Dinerstein, Harriet L.
Peeters, Els
Sterling, N. C.
Cami, Jan
Barlow, M. J.
Kastner, Joel
Walsh, Jeremy R.
Waters, L. B. F. M.
Hirano, Naomi
Aleman, Isabel
Bernard-Salas, Jeronimo
Bhatt, Charmi
Blommaert, Joris
Clark, Nicholas
Jones, Olivia
Justtanont, Kay
Kemper, F.
Kraemer, Kathleen E.
Lagadec, Eric
Laming, J. Martin
Molster, F. J.
Baez, Paula Moraga
Monteiro, H.
Richards, Anita M S
Sahai, Raghvendra
Sloan, G. C.
Torki, Maryam
van Hoof, Peter A. M.
Wright, Nicholas J.
Wilson, Finnbar
Csukai, Alexander
author_facet Matsuura, Mikako
Volk, Kevin
Kavanagh, Patrick
Balick, Bruce
Wesson, Roger
Zijlstra, Albert A.
Dinerstein, Harriet L.
Peeters, Els
Sterling, N. C.
Cami, Jan
Barlow, M. J.
Kastner, Joel
Walsh, Jeremy R.
Waters, L. B. F. M.
Hirano, Naomi
Aleman, Isabel
Bernard-Salas, Jeronimo
Bhatt, Charmi
Blommaert, Joris
Clark, Nicholas
Jones, Olivia
Justtanont, Kay
Kemper, F.
Kraemer, Kathleen E.
Lagadec, Eric
Laming, J. Martin
Molster, F. J.
Baez, Paula Moraga
Monteiro, H.
Richards, Anita M S
Sahai, Raghvendra
Sloan, G. C.
Torki, Maryam
van Hoof, Peter A. M.
Wright, Nicholas J.
Wilson, Finnbar
Csukai, Alexander
contents NGC 6302 is a spectacular bipolar planetary nebula (PN) whose spectrum exhibits fast outflows and highly ionized emission lines, indicating the presence of a very hot central star (~220,000 K). Its infrared spectrum reveals a mixed oxygen and carbon dust chemistry, displaying both silicate and polycyclic aromatic hydrocarbon (PAH) features. Using the JWST Mid-Infrared Instrument (MIRI) and Medium Resolution Spectrometer, a mosaic map was obtained over the core of NGC 6302, covering the wavelength range of 5--28 micron and spanning an area of ~18.5 arcsec x15 arcsec. The spatially resolved spectrum reveals ~200 molecular and ionized lines from species requiring ionisation potentials of up to 205 eV. The spatial distributions highlight a complex structure at the nebula's centre. Highly ionized species such as Mg VII and Si VII show compact structures, while lower-ionization species such as H^+ extend much farther outwards, forming filament-defined rims that delineate a bubble. Within the bubble, the H^+ and H_2 emission coincide, while the PAH emission appears farther out, indicating an ionization structure distinct from typical photodissociation regions, such as the Orion Bar. This may be the first identification of a PAH formation site in a PN. This PN appears to be shaped not by a steady, continuous outflow, but by a series of dynamic, impulsive bubble ejections, creating local conditions conducive to PAH formation. A dusty torus surrounds the core, primarily composed of large (micron-sized) silicate grains with crystalline components. The long-lived torus contains a substantial mass of material, which could support an equilibrium chemistry and a slow dust-formation process.
format Preprint
id arxiv_https___arxiv_org_abs_2508_19332
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The JWST/MIRI view of the planetary nebula NGC 6302 I.: a UV irradiated torus and a hot bubble triggering PAH formation
Matsuura, Mikako
Volk, Kevin
Kavanagh, Patrick
Balick, Bruce
Wesson, Roger
Zijlstra, Albert A.
Dinerstein, Harriet L.
Peeters, Els
Sterling, N. C.
Cami, Jan
Barlow, M. J.
Kastner, Joel
Walsh, Jeremy R.
Waters, L. B. F. M.
Hirano, Naomi
Aleman, Isabel
Bernard-Salas, Jeronimo
Bhatt, Charmi
Blommaert, Joris
Clark, Nicholas
Jones, Olivia
Justtanont, Kay
Kemper, F.
Kraemer, Kathleen E.
Lagadec, Eric
Laming, J. Martin
Molster, F. J.
Baez, Paula Moraga
Monteiro, H.
Richards, Anita M S
Sahai, Raghvendra
Sloan, G. C.
Torki, Maryam
van Hoof, Peter A. M.
Wright, Nicholas J.
Wilson, Finnbar
Csukai, Alexander
Solar and Stellar Astrophysics
Astrophysics of Galaxies
NGC 6302 is a spectacular bipolar planetary nebula (PN) whose spectrum exhibits fast outflows and highly ionized emission lines, indicating the presence of a very hot central star (~220,000 K). Its infrared spectrum reveals a mixed oxygen and carbon dust chemistry, displaying both silicate and polycyclic aromatic hydrocarbon (PAH) features. Using the JWST Mid-Infrared Instrument (MIRI) and Medium Resolution Spectrometer, a mosaic map was obtained over the core of NGC 6302, covering the wavelength range of 5--28 micron and spanning an area of ~18.5 arcsec x15 arcsec. The spatially resolved spectrum reveals ~200 molecular and ionized lines from species requiring ionisation potentials of up to 205 eV. The spatial distributions highlight a complex structure at the nebula's centre. Highly ionized species such as Mg VII and Si VII show compact structures, while lower-ionization species such as H^+ extend much farther outwards, forming filament-defined rims that delineate a bubble. Within the bubble, the H^+ and H_2 emission coincide, while the PAH emission appears farther out, indicating an ionization structure distinct from typical photodissociation regions, such as the Orion Bar. This may be the first identification of a PAH formation site in a PN. This PN appears to be shaped not by a steady, continuous outflow, but by a series of dynamic, impulsive bubble ejections, creating local conditions conducive to PAH formation. A dusty torus surrounds the core, primarily composed of large (micron-sized) silicate grains with crystalline components. The long-lived torus contains a substantial mass of material, which could support an equilibrium chemistry and a slow dust-formation process.
title The JWST/MIRI view of the planetary nebula NGC 6302 I.: a UV irradiated torus and a hot bubble triggering PAH formation
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2508.19332