Results 11 to 20 of about 2,475,342 (218)

Dynamics and photodissociation region properties in IC 1396A [PDF]

Astronomy & Astrophysics, 2012
Aims. We investigate the gas dynamics and the physical properties of photodissociation regions (PDRs) in IC 1396A, which is an illuminated bright-rimmed globule with internal structures created by young stellar objects. Methods. Our mapping observations of the [C ii] emission in IC 1396A with GREAT onboard SOFIA revealed the detailed velocity structure
Okada, Y., Güsten, R., Requena-Torres, M., Röllig, M., Hartogh, P., Hübers, H., Klein, T., Ricken, O., Simon, R., Stutzki, J.   +9 more
openaire   +3 more sources

Surface chemistry in photodissociation regions [PDF]

Astronomy & Astrophysics, 2016
The presence of dust can strongly affect the chemical composition of the interstellar medium. We model the chemistry in photodissociation regions (PDRs) using both gas-phase and dust-phase chemical reactions. Our aim is to determine the chemical compositions of the interstellar medium (gas/dust/ice) in regions with distinct (molecular) gas densities ...
Esplugues, G., Cazaux, .S., Meijerink, R., Spaans, M., Caselli, P.   +4 more
openaire   +7 more sources

JWST observations of photodissociation regions

Astronomy & Astrophysics
Context. The northwest photodissociation region (PDR) of the NGC 7023 reflection nebula has been observed with JWST spectroscopy, revealing the carbonaceous emission bands at a high level of detail.
Van De Putte D., Gordon K. D., Misselt K., Witt A. N., Abergel A., Noriega-Crespo A., Guillard P., Zannese M., Elyajouri M., Trahin B., Dell’ova P., Baes M., Klaassen P.   +12 more
doaj   +3 more sources

The Resolved Structure of a Low-metallicity Photodissociation Region

The Astrophysical Journal
Photodissociation regions (PDRs) are key to understanding the feedback processes that shape interstellar matter in galaxies. One important type of PDR is the interface between H ii regions and molecular clouds, where far-ultraviolet radiation from ...
Ilyse Y. Clark, Karin Sandstrom, Mark Wolfire, Alberto D. Bolatto, Jérémy Chastenet, Daniel A. Dale, Brandt A. L. Gaches, Simon C. O. Glover, Javier R. Goicoechea, Karl D. Gordon, Brent Groves, Lindsey Hands, Ralf Klessen, Ilse De Looze, J. D. T. Smith, Dries Van De Putte, Stefanie K. Walch   +16 more
doaj   +5 more sources

Action Spectroscopy of Mass‐Selected Ions—From Principles to Applications [PDF]

Journal of Mass Spectrometry, Volume 61, Issue 10, October 2026.
ABSTRACT Gas‐phase ion spectroscopy provides direct, structure‐sensitive information that complements and extends conventional mass spectrometry workflows, offering structural resolution that accurate mass and fragmentation patterns alone cannot always achieve by themselves.
Pedro Henrique Martins Garcia, Gustavo Cervi, Cesar Augusto Gonçalves Dantas, Guilherme Obeid, Thiago C. Correra   +4 more
wiley   +2 more sources

Dust processing in photodissociation regions [PDF]

Astronomy & Astrophysics, 2008
Mid-infrared spectroscopy of dense illuminated ridges (or photodissociation regions, PDRs) suggests dust evolution. Such evolution must be reflected in the gas physical properties through processes like photo-electric heating or H_2 formation. With Spitzer Infrared Spectrograph (IRS) and ISOCAM data, we study the mid-IR emission of closeby, well known ...
Compiegne, M., Abergel, A., Verstraete, L., Habart, E.   +3 more
openaire   +3 more sources

C₆₀IN PHOTODISSOCIATION REGIONS [PDF]

The Astrophysical Journal, 2014
Recent studies have confirmed the presence of buckminsterfullerene (C$_{60}$) in different interstellar and circumstellar environments. However, several aspects regarding C$_{60}$ in space are not well understood yet, such as the formation and excitation processes, and the connection between C$_{60}$ and other carbonaceous compounds in the interstellar
Castellanos, Pablo; Berné, Olivier; Sheffer, Yaron; Wolfire, Mark G.; Tielens, Alexander G. G. M.   +5 more
openaire   +2 more sources

Turbulent mixing in photodissociation regions [PDF]

Molecular clouds are dynamic environments where species are transported through random motions. To fully understand the physical conditions within these clouds, it is essential to quantify this transport. This study focused on the diffusion effects in the multi-fluid gas of photodissociation regions (PDRs) by considering turbulent, molecular, and ...
Baby, Aleena
openaire   +2 more sources

Photodissociation of singlet oxygen in the UV region [PDF]

Physical Chemistry Chemical Physics, 2014
Photodissociation of singlet oxygen, O2 a(1)Δg, by ultraviolet radiation in the region from 200 to 240 nm has been investigated using velocity map imaging of the atomic oxygen photofragments. Singlet oxygen molecules are generated in a pulsed discharge and studied by one-laser photodissociation and detection around 226 nm as well as two color ...
Farooq, Z., Chestakov, D.A., Yan, B., Groenenboom, G.C., Zande, W.J. van der, Parker, D.H.   +5 more
openaire   +3 more sources

Photodissociation and X-Ray-Dominated Regions

Annual Review of Astronomy and Astrophysics, 2022
The radiation from stars and active galactic nuclei (AGNs) creates photodissociation regions (PDRs) and X-ray-dominated regions (XDRs), where the chemistry or heating is dominated by far-ultraviolet (FUV) radiation or X-ray radiation, respectively.
Wolfire, Mark G., Vallini, Livia, Chevance, Mélanie   +2 more
openaire   +2 more sources