Astronomy and Astrophysics – Astronomy
Scientific paper
May 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006apj...643l..25h&link_type=abstract
The Astrophysical Journal, Volume 643, Issue 1, pp. L25-L28.
Astronomy and Astrophysics
Astronomy
33
Ism: Abundances, Ism: Clouds, Ism: Individual: Name: Sagittarius B2(N-Lmh), Ism: Molecules, Radio Lines: Ism
Scientific paper
Acetamide (CH3CONH2) has been detected in emission and absorption toward the star-forming region Sagittarius B2(N) with the 100 m Green Bank Telescope (GBT) by means of four A-species and four E-species rotational transitions. All transitions have energy levels less than 10 K. The Sgr B2(N) cloud is known to have a cold halo with clumps of gas at several different velocities. Absorption features are largely characterized by local standard of rest (LSR) velocities that are typical of the two star-forming cores with systemic LSR velocities of +64 and +82 km s-1. Continuum sources embedded within the star-forming cores give rise to the absorption from the molecular gas halo surrounding the cores. Emission features are seen at an approximate intermediate LSR velocity of +73 km s-1 that characterizes the widespread molecular halo that has a spatial scale of a few arcminutes. Two low-energy transitions of formamide (HCONH 2) were also observed with the GBT toward Sagittarius B2(N) since formamide is the potential parent molecule of acetamide; both molecules are the only interstellar species with an NH2 group bound to a CO group, the so-called peptide bond, that provides the linkage for the polymerization of amino acids. While the acetamide transitions observed appear to be confined to the cold (~8 K) halo region, only the 101-0 00 transition of formamide appears to be exclusively from the cold halo; the 312-313 transition of formamide is apparently contaminated with emission from the two hot cores. The relative abundance ratio of acetamide to formamide is estimated to be in the range of ~0.1 to ~0.5 in the cold halo. The exothermic neutral-radical reaction of formamide with methylene (CH2) may account for the synthesis of interstellar acetamide in the presence of shock phenomenon in this star-forming region.
Hollis Jan. M.
Ilyushin Vadim V.
Jewell Phil R.
Kleiner Isabelle
Lovas Francis J.
No associations
LandOfFree
Detection of Acetamide (CH3CONH2): The Largest Interstellar Molecule with a Peptide Bond does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Detection of Acetamide (CH3CONH2): The Largest Interstellar Molecule with a Peptide Bond, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Detection of Acetamide (CH3CONH2): The Largest Interstellar Molecule with a Peptide Bond will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1029281