Sökning: "isotopologues"

Visar resultat 1 - 5 av 9 avhandlingar innehållade ordet isotopologues.

1. 1. Mid- and near-infrared NICE-OHMS : techniques for ultra-sensitive detection of molecules in gas phase

   Författare :Thomas Hausmaninger; Ove Axner; Kyle Crabtree; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spectrometry; NICE-OHMS; trace gas detection; acetylene; methane; isotopologues; near-infrared; mid-infrared; shot-noise; optical parametric oscillator; teknisk fysik med inriktningen mikrosystemteknik; engineering science with specialization in microsystems technology;

   Sammanfattning : Noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) is a technique for ultra-sensitive detection of molecular absorption and dispersion. For highest performance, the technique combines cavity enhancement (CE) with frequency modulation (FM); while the former increases the effective interaction length between the light and the analyte by several orders of magnitudes, the latter removes the in-coupling of 1/f noise and makes the signals background free. LÄS MER

3. 2. Satellite and ground based observations of massive star forming regions

   Författare :Henrik Olofsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; abundances - ISM; ISM; clouds - ISM; jets and outflows - ISM; ISM - Submillimeter; molecules - Radio lines;

   Sammanfattning : Results from submm/mm radio astronomical observations, using the astronomy/-aeronomy satellite Odin and the 20m telescope at the Onsala Space Observatory, are presented. Analysis of spectroscopic data of interstellar rotational emission lines from gaseous H2O residing in giant molecular clouds (GMCs), reveal important new clues about the chemistry and spatial distribution of water molecules in these regions, including estimates of the water abundance in molecular outflows associated with massive star formation. LÄS MER

4. 3. Astrochemistry at Millimetre and Submillimetre Wavelengths

   Författare :Eva Wirström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Astrobiology - Astrochemistry - ISM: abundances - ISM: molecules - Submillimetre;

   Sammanfattning : The focus of this thesis is a series of observational tests, aiming to clarify the chemical and physical origin of interstellar molecules. Spectral lines at millimetre and submillimetre wavelengths, caused by rotational transitions in CO, H2O, NH3, CH3OH, CH3SH, C2H3CN, and several of their isotopologues, have been observed towards regions of star-formation in the Galaxy. LÄS MER

5. 4. Molecular observations at high and low redshifts with the Odin satellite

   Författare :Carina Persson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ISM: abundances -- ISM: molecules -- ISM: individual Orion KL -- ISM: individual S140 -- Radio lines: ISM -- Submillimeter -- Line: profiles -- Line: formation -- Cosmology: early Universe -- Cosmology: observations;

   Sammanfattning : The papers in this thesis have the aim of expanding our knowledge of different processes related to star formation in the early Universe and at present times. A complex chemistry occurs in star forming clouds and by observing molecules, information about the necessary physical and chemical conditions for star formation can be obtained. LÄS MER

7. 5. Molecular Astrophysics in Star-forming Regions with the Odin Satellite

   Författare :Carina Persson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The interstellar medium is the cradle of life, stars and planets in the evolving Universe. Stars are born deep inside cold and dark molecular clouds, and affect the dynamical conditions in local regions by powerful winds, outflows, and by supernova explosions. LÄS MER