Download or read book Submillimeter Laboratory Investigations written by Eric Herbst and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Our group was the first to extend studies of the rotational spectra of small and fundamental gas-phase molecules from the microwave into first the millimeter-wave and subsequently the submillimeter-wave region of the spectrum(King & Gordy 1953;Helmingeret al. 1970,1983).A bibliography of the many molecules studied in the laboratory, consisting of over400 papers, is available upon request. The results presented in these papers provide the basis for the identification of a significant fraction of the interstellar spectral lines. For interstellar molecules previously detected at lower frequencies, our submillimeter-wave spectra provide the opportunity for additional study of these species under warmer conditions. For the duration of this proposal and previously, we have concentrated on those molecules with the Largest number of interstellar spectral lines. These species are so-called internal rotors, in which one portion of the molecule(normally a methyl (CH3) group) undergoes a hindered rotational motion with respect to the other portion of the molecule. The hindered rotational motion, known as torsion, leads to quantized states typically separated by 50-100 K and labeled with a quantum number vt= 0,1,2 ... For the three-fold case, each torsional state is also split into two substates-designated A and E. The existence of these extra states compared with normal molecules is of great use for probing warm regions with temperatures too low to excite normal vibrations but higher than the ambient interstellar medium. Strong interactions between torsional and rotational motion, however, make the spectra of some internal rotors quite complex and, for many years, it was very difficult if not impossible to analyze their spectra to microwave accuracy. Without such a detailed analysis, it is not possible to predict the frequencies of the many lines not measured in the laboratory with sufficient precision for use by radio astronomers, nor to determine intensities."--Page 2.

Download or read book Millimeter submillimeter Wavelength Spectroscopy of Prebiotic Interstellar Molecules with Complex Internal Motion written by Connor Jorden Wright and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry of the Interstellar Medium (ISM) is now known to be rich, highly complex, and highly heterogeneous. The identification of over 240 molecular species to date, several of them prebiotic in nature, has been driven entirely by first detecting and characterizing their spectra in the laboratory. Due to the structure specific nature of rotational spectroscopy, the bulk of said identifications have come from spectral line identifications with radio telescopes at microwave, millimeter, and submillimeter wavelengths. The laboratory assignment of rotational transitions can, however, become complicated by certain structural components of the molecules under investigation. Transition splittings caused by internal rotation, nuclear spin, or unpaired electron spin can make identification of molecules possessing these features difficult, especially in telescope data with overlapping molecular signals. Therefore, the spectra of three molecules with these complex internal motions (two of which are potential precursors to amino acids or other biologically relevant molecules in the ISM) have been investigated in the millimeter/submillimeter regime: pyruvic acid (CH3COCOOH), the argon-methanol van der Waals cluster (Ar-CH3OH), and the aminomethyl radical (CH2NH2). Collection, assignment, and fits of their rotational spectra allow for future astronomical searches and identification. The results of the laboratory investigations and some preliminary searches in interstellar spectra are presented herein.

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1992 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Infrared Submillimeter and Radio Astronomy Research and Analysis Program written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-26 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program entitled "Infrared Submillimeter and Radio Astronomy Research and Analysis Program" with NASA-Ames Research Center (ARC) was proposed by the Smithsonian Astrophysical Observatory (SAO) to cover three years. Due to funding constraints only the first year installment of $18,436 was funded, but this funding was spread out over two years to try to maximize the benefit to the program. During the tenure of this contact, the investigators at the SAO, Drs. Wesley A. Traub and Nathaniel P. Carleton, worked with the investigators at ARC, Drs. Jesse Bregman and Fred Wittebom, on the following three main areas: 1. Rapid scanning SAO and ARC collaborated on purchasing and constructing a Rapid Scan Platform for the delay arm of the Infrared-Optical Telescope Array (IOTA) interferometer on Mt. Hopkins, Arizona. The Rapid Scan Platform was tested and improved by the addition of stiffening plates which eliminated a very small but noticeable bending of the metal platform at the micro-meter level. 2. Star tracking Bregman and Wittebom conducted a study of the IOTA CCD-based star tracker system, by constructing a device to simulate star motion having a specified frequency and amplitude of motion, and by examining the response of the tracker to this simulated star input. 3. Fringe tracking. ARC, and in particular Dr. Robert Mah, developed a fringe-packet tracking algorithm, based on data that Bregman and Witteborn obtained on IOTA. The algorithm was tested in the laboratory at ARC, and found to work well for both strong and weak fringes. Traub, Wesley A. Ames Research Center

Download or read book Problems and Programs on the Use of Submillimeter Waves in Space written by Max R. Nagel and published by . This book was released on 1968 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA s University Program Active Projects written by and published by . This book was released on with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Research in Progress written by and published by . This book was released on 1987 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Development and Application of SubLIME written by Katarina Marie Yocum and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in this dissertation involved the development of a laboratory technique to reveal new information about cosmic ice chemistry. The Sublimation of Laboratory Ices Millimeter/submillimeter Experiment (SubLIME) combines millimeter and submillimeter (mm/submm) spectroscopy, infrared spectroscopy, and mass spectrometry to explore the connection between ice and gas chemistry in cold regions of space by studying the intricate details of sublimation. The studies examined ice chemistry driven by UV photons, how those chemical reactions differ under temperature variations, and how UV photons and heat effect the sublimation process. Procedures were developed for determining surface binding energy, sublimation enthalpy, rotational temperature, and gas density. The millimeter/submillimeter spectroscopic technique can unambiguously identify structural isomers, conformational isomers, and isotopologues, making it highly complementary to previous gas-phase mass spectrometry techniques typically implemented for laboratory cosmic ice studies. Furthermore, the laboratory spectra are directly comparable to observational data from submillimeter/far-IR telescopes and provide an avenue for laboratory modeling of telescope data to guide future observational discoveries.

Download or read book Spectroscopy from Space written by Jean Demaison and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many satellites have recently been launched or are in preparation, which operate in the microwave to IR ranges, the main objective being to observe the earth's atmosphere or interstellar clouds. Analysis of the data they supply requires extensive laboratory work because we still only have sufficiently accurate data (line positions, intensities, and profiles) for only a few species. Furthermore, the observer community is making increasing calls for laboratory data, as new development open up new observational possibilities (such as submillimeter observation). Research on these subjects involves many different areas of specialisation in fields of research that generate a wealth of data. In Spectroscopy from Space the people responsible for field observations explain which results they are expecting from their measurements and how laboratory people can help them to analyse their satellite data. Laboratory spectroscopists explain why what they can do now, and what kinds of experiment and theoretical development that might undertake to meet the needs of the remote sensing community. The problems of distributing reliable laboratory data in a timely way are also addressed.

Download or read book Research and Technology Objectives and Plans Summary RTOPS written by and published by . This book was released on 1993 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Spectral Resolution Infrared Remote Sensing for Earth s Weather and Climate Studies written by Alain Chedin and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of major challenges facing Earth's science in the next decade and beyondis the development of an accurate long term observational data set to study global change. To accomplish this, a wide range of observations will be required to provide both new measurements, not previously achievable and measurements with a greater degreee of accuracy and resolution than the ones which are presently and currently available. Among the parameters that are currently retrieved from satellite vertical sounding observations, temperature and moisture profiles are the most important for the description of the thermodynamic state of the medium. Other parameters, like those describing the cloud fields, the surface state or the conditions close to the surface are also key parameters for meteorology and climatology. A new generation of high spectral atmospheric sounders in the infrared has recently been designed to provide both new and more accurate data about the atmosphere, land and oceans for application to climate studies. Among the important observations that these instruments should contribute to the climate data set are day and night global measurements of: atmospheric temperature profiles; relative humidity profiles; cloud field parameters; total ozone burden of the atmosphere; distribution of minor atmospehric gases (methane, carbonmonoxide and nitrous oxide).

Download or read book Basic Investigations of the Possibilities to Advance Into the Submillimeter Region written by Louis Richard Bloom and published by . This book was released on 1952 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA University Program Management Information System FY 1993 written by and published by . This book was released on 1993 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Passive Atmospheric Sounding Using Millimeter and Submillimeter Wavelength Channels written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-05 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Progress by the Georgia Institute of Technology's Laboratory for Radio-science and Remote Sensing in developing techniques for passive microwave retrieval of water vapor profiles and cloud and precipitation parameters using millimeter and submillimeter wavelength channels is reviewed. Channels of particular interest are in the tropospheric transmission windows at 90, 166, 220, 340, and 410 GHz and centered around the water vapor lines at 183 and 325 GHz. Collectively, these channels have potential application in high-resolution precipitation mapping (e.g., from geosynchronous orbit), remote sensing of cloud and precipitation parameters, including cirrus ice mass, and improved retrieval of water vapor profiles. During the period from January 1, 1994 through June 30, 1994 research activities focussed on calibrating and interpreting data from the Millimeter-Wave Imaging Radiometer (MIR). The MIR was deployed on the NASA ER-2 during the Convective Atmospheric Moisture Experiment (CAMEX, September-October 1993) to obtain the first submillimeter-wave tropospheric imagery of convective precipitations. A 325-GHz radiometer consisted of a submillimeter-wave DSB receiver with three IF channels at +/- 1, 3, and 8.5 GHz, and approximately 14 dB DSB noise figure was successfully operated during these experiments. Activities supported under this grant include a study of the impact of local oscillator reflections from the MIR calibration loads, the development of optimal gain and offset filters for radiometric calibration, and the modeling and interpretation of the MIR 325-GHz data over both clear and cloudy atmospheres. In addition, polarimetric radiometer measurements and modeling for ocean surface and atmospheric cloud-ice studies_were supported. Gasiewski, Albin J. and Kunkee, D. B. and Jackson, D. M. and Blackwell, W. and Sharpe, S. Unspecified Center NAG5-1490...

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 902 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA University Program Management Information System FY 1995 written by and published by . This book was released on 1995 with total page 672 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1981 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: