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Updated: Feb 15, 2026

Mechanical Micronization of Lipoaspirates for Regenerative Therapy

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The interstellar 4.62 micron band.

Y J Pendleton¹, A G Tielens, A T Tokunaga

¹NASA Ames Research Center, Moffett Field, CA 94035, USA.

The Astrophysical Journal

|September 7, 2001

Summary

This summary is machine-generated.

Researchers analyzed protostar spectra, identifying a broad absorption band near 4.62 microns. This "X-C triple bond N" band

Keywords:

NASA Center ARC NASA Discipline Exobiology

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Area of Science:

Astrochemistry
Spectroscopy
Interstellar Medium

Background:

Protostars exhibit unique spectral features due to their surrounding ices.
A broad absorption band near 4.62 microns, the "X-C triple bond N" band, is observed in protostellar spectra.
The precise carrier and formation pathways of this band remain debated.

Purpose of the Study:

To present new infrared spectra of embedded protostars.
To analyze the characteristics of the interstellar "X-C triple bond N" band.
To investigate potential carriers and formation mechanisms for the observed band.

Main Methods:

Acquisition of 4.5-5.1 micron spectra for five embedded protostars.
Analysis of spectral band positions and widths.
Comparison of band strengths with other ice absorption features.

Main Results:

Observed peak positions and widths of the interstellar band agree with literature values.
No correlation was found between the 4.62 micron band strength and other ice features, suggesting diverse ice environments.
Organic residues from ion bombardment or the OCN- ion from acid-base reactions/photolysis show good spectral fits.

Conclusions:

The diversity of interstellar ice environments influences the observed "X-C triple bond N" band.
Ion bombardment of nitrogen-containing ices or OCN- formation are plausible pathways for the band's origin.
Further research can elucidate the exact composition and formation of this significant interstellar feature.