In-situ Probing of Radiation-induced Processing of Organics in Astrophysical Ice Analogs—Novel Laser Desorption Laser Ionization Time-of-flight Mass Spectroscopic Studies

@article{Gudipati2012InsituPO,
  title={In-situ Probing of Radiation-induced Processing of Organics in Astrophysical Ice Analogs—Novel Laser Desorption Laser Ionization Time-of-flight Mass Spectroscopic Studies},
  author={M. Gudipati and Rui Yang},
  journal={The Astrophysical Journal},
  year={2012},
  volume={756}
}
Understanding the evolution of organic molecules in ice grains in the interstellar medium (ISM) under cosmic rays, stellar radiation, and local electrons and ions is critical to our understanding of the connection between ISM and solar systems. Our study is aimed at reaching this goal of looking directly into radiation-induced processing in these ice grains. We developed a two-color laser-desorption laser-ionization time-of-flight mass spectroscopic method (2C-MALDI-TOF), similar to matrix… Expand

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References

SHOWING 1-10 OF 51 REFERENCES
Photochemistry of polycyclic aromatic hydrocarbons in cosmic water ice - II. Near UV/VIS spectroscopy and ionization rates
Context. Mid-infrared emission features originating from polycyclic aromatic hydrocarbons (PAHs) are observed towards photon dominated regions in space. Towards dense clouds, however, these emissionExpand
Facile Generation and Storage of Polycyclic Aromatic Hydrocarbon Ions in Astrophysical Ices
In situ ultraviolet-visible absorption and emission studies of vacuum ultraviolet (VUV) irradiated water-rich, cosmic ice analogs containing polycyclic aromatic hydrocarbons (PAHs) are described. VUVExpand
Photochemistry of polycyclic aromatic hydrocarbons in cosmic water ice. I. Mid-IR spectroscopy and photoproducts
Context. Polycyclic aromatic hydrocarbons (PAHs) are known to be abundantly present in photon-dominated regions (PDRs), as evidenced by their ubiquitous mid-IR emission bands. Towards dense clouds,Expand
Infrared laser ablation and ionization of water clusters and biomolecules from ice
Abstract We demonstrate the direct desorption and ionization of angiotensin II from frozen water ice samples without supplementary matrix, using a pulse train of approximately 340 intense (∼109Expand
Photochemistry of the PAH pyrene in water ice: the case for ion-mediated solid-state astrochemistry
Context. Icy dust grains play an important role in the formation of complex molecules in the interstellar medium (ISH). Laboratory studies have mainly focused on the physical interactions andExpand
Matrix-isolation in cryogenic water-ices: Facile generation, storage, and optical spectroscopy of aromatic radical cations
Radical cations of naphthalene and 4-methylpyrene have been generated for the first time in high conversion efficiencies in cryogenic water-ices at 15 K through vacuum ultraviolet photolysis. WithExpand
Ice as a matrix for IR-matrix-assisted laser desorption/ionization: mass spectra from a protein single crystal.
TLDR
Results are presented that show that IR-MALDI of lyophilized proteins, air dried protein solutions, or protein crystals up to a molecular mass of 30 kDa is possible without the addition of any separate matrix. Expand
Real-Time Optical Spectroscopy of Vacuum Ultraviolet Irradiated Pyrene:H2O Interstellar Ice
This paper describes a near-UV/VIS study of a pyrene:H2O interstellar ice analogue at 10 K using optical absorption spectroscopy. A new experimental approach makes it possible to irradiate the sampleExpand
Laboratory Studies on the Formation of Formic Acid (HCOOH) in Interstellar and Cometary Ices
Mixtures of water (H2O) and carbon monoxide (CO) ices were irradiated at 10 K with energetic electrons to simulate the energy transfer processes that occur in the track of galactic cosmic-rayExpand
An experimental study of the organic molecules produced in cometary and interstellar ice analogs by thermal formaldehyde reactions.
TLDR
It is estimated that about 1% of the organics found in the coma of Comet Halley could have been produced by thermal formaldehyde reactions taking place in the nucleus. Expand
...
1
2
3
4
5
...