On the Origin of Infrared Bands Attributed to Tryptophan in Spitzer Observations of IC 348

Aditya Dhariwal; Thomas H. Speak; Linshan Zeng; Amirhossein Rashidi; Brendan Moore; Olivier Berné; Anthony J. Remijan; Ilane Schroetter; Brett A. McGuire; Víctor M. Rivilla; Arnaud Belloche; Jes K. Jørgensen; Pavle Djuricanin; Takamasa Momose; Ilsa R. Cooke

doi:10.3847/2041-8213/ad4d9a

The Astrophysical Journal Letters (Jan 2024)

On the Origin of Infrared Bands Attributed to Tryptophan in Spitzer Observations of IC 348

Aditya Dhariwal,
Thomas H. Speak,
Linshan Zeng,
Amirhossein Rashidi,
Brendan Moore,
Olivier Berné,
Anthony J. Remijan,
Ilane Schroetter,
Brett A. McGuire,
Víctor M. Rivilla,
Arnaud Belloche,
Jes K. Jørgensen,
Pavle Djuricanin,
Takamasa Momose,
Ilsa R. Cooke

Affiliations

Aditya Dhariwal: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Thomas H. Speak: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Linshan Zeng: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Amirhossein Rashidi: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Brendan Moore: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Olivier Berné: Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse , CNRS, CNES, UPS, Toulouse, France
Anthony J. Remijan: ORCiD; National Radio Astronomy Observatory , Charlottesville, VA 22903, USA
Ilane Schroetter: ORCiD; Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse , CNRS, CNES, UPS, Toulouse, France
Brett A. McGuire: ORCiD; National Radio Astronomy Observatory , Charlottesville, VA 22903, USA; Department of Chemistry, Massachusetts Institute of Technology , Cambridge, MA 02139, USA
Víctor M. Rivilla: ORCiD; Centro de Astrobiologıa (CAB) , INTA-CSIC, Carretera de Ajalvir km 4, Torrejón de Ardoz, 28850 Madrid, Spain
Arnaud Belloche: ORCiD; Max-Planck-Institut für Radioastronomie (MPIfR) , Auf dem Hügel 69, 53121 Bonn, Germany
Jes K. Jørgensen: ORCiD; Niels Bohr Institute, University of Copenhagen , Øster Voldgade 5–7, DK-1350 Copenhagen K., Denmark
Pavle Djuricanin: Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Takamasa Momose: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]
Ilsa R. Cooke: ORCiD; Department of Chemistry, University of British Columbia , 2036 Main Mall, Vancouver BC V6T 1Z1, Canada ; [email protected]

DOI: https://doi.org/10.3847/2041-8213/ad4d9a
Journal volume & issue: Vol. 968, no. 1
p. L9

Abstract

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Infrared emission features toward interstellar gas of the IC 348 star cluster in Perseus have been recently proposed to originate from the amino acid tryptophan. The assignment was based on laboratory infrared spectra of tryptophan pressed into pellets, a method which is known to cause large frequency shifts compared to the gas phase. We assess the validity of the assignment based on the original Spitzer data as well as new data from JWST. In addition, we report new spectra of tryptophan condensed in para-hydrogen matrices to compare with the observed spectra. The JWST MIRI data do not show evidence for tryptophan, despite deeper integration toward IC 348. In addition, we show that several of the lines attributed to tryptophan are likely due to instrumental artifacts. This, combined with the new laboratory data, allows us to conclude that there is no compelling evidence for the tryptophan assignment.

Published in The Astrophysical Journal Letters

ISSN: 2041-8205 (Print); 2041-8213 (Online)
Publisher: IOP Publishing
Country of publisher: United Kingdom
LCC subjects: Science: Astronomy: Astrophysics
Website: https://iopscience.iop.org/journal/2041-8205

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