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Detection of Water Vapor in the Thermal Spectrum of the Non-transiting Hot Jupiter Upsilon Andromedae bPiskorz, Danielle, Benneke, Björn, Crockett, Nathan R., Lockwood, Alexandra C., Blake, Geoffrey A., Barman, Travis S., Bender, Chad F., Carr, John S., Johnson, John A. 01 August 2017 (has links)
The Upsilon Andromedae system was the first multi-planet system discovered orbiting a main-sequence star. We describe the detection of water vapor in the atmosphere of the innermost non-transiting gas giant ups. And. b by treating the star-planet system as a spectroscopic binary with high-resolution, ground-based spectroscopy. We resolve the signal of the planet's motion and break the mass-inclination degeneracy for this non-transiting planet via deep combined flux observations of the star and the planet. In total, seven epochs of Keck NIRSPEC L band observations, three epochs of Keck NIRSPEC short-wavelength K band observations, and three epochs of Keck NIRSPEC long wavelength K band observations of the ups. And. system were obtained. We perform a multi-epoch cross-correlation of the full data set with an atmospheric model. We measure the radial projection of the Keplerian velocity (K-P = 55 +/- 9 km s(-1)), true mass (M-b = 1.7(-0.24)(+0.33)M(J)), and orbital inclination (i(b) 24 degrees +/- 4 degrees), and determine that the planet's opacity structure is dominated by water vapor at the probed wavelengths. Dynamical simulations of the planets in the ups. And. system with these orbital elements for ups. And. b show that stable, long-term (100 Myr) orbital configurations exist. These measurements will inform future studies of the stability and evolution of the ups. And. system, as well as the atmospheric structure and composition of the hot Jupiter.
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High-resolution UV-Vis-NIR fourier transform imaging spectroscopy and its applications in biology and chemistryLi, Jianping 01 January 2010 (has links)
No description available.
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The role of the counter rotating terms in spontaneous emission and the time evolution of lamb shiftLi, Zhenghong 01 January 2012 (has links)
No description available.
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Phase-Dependent Spectroscopy of Mira Variable StarsCastelaz, Michael W., Luttermoser, Donald G., Caton, Daniel B., Piontek, Robert A. 01 January 2000 (has links)
Spectroscopic measurements of Mira variable stars as a function of phase probe the stellar atmospheres and underlying pulsation mechanisms. For example, measuring variations in TiO, VO, and ZrO with phase can be used to help determine whether these molecular species are produced in an extended region above the layers where Balmer line emission occurs or below this shocked region. Using the same methods, the Balmer line increment, where the strongest Balmer line at phase zero is Hδ and not Hα, can be measured and explanations tested, along with another peculiarity, the absence of the H∈ line in the spectra of Mira variables when the other Balmer lines are strong. We present new spectra covering the spectral range from 6200 to 9000 Å of 20 Mira variables. A relationship between variations in the Ca II IR triplet and Hα as a function of phase support the hypothesis that H∈'s observational characteristics result from an interaction of H∈ photons with the Ca II H line. New periods and epochs of variability are also presented for each star.
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Kinetic spectroscopic quantification of biomarkers in practical samplesPeng, Weiyu 06 August 2021 (has links)
Kinetic spectroscopic quantification refers to a subset of chromogenic (CG) and fluorogenic (FG) assays that deduce analyte concentration based on the UV-vis or fluorescence signal obtained during the CG/FG reaction processes. Existing kinetic spectroscopic quantification are based predominantly on reactions that can be approximated as a first-order process. Presented in this thesis is the kinetic spectroscopic quantification that uses higher order CG/FG reactions where the overall reaction can be approximated as combination of two sequential first-order processes. Included in chapter one is the theoretical model and several proof-of-concept applications. This model analyte is malondialdehyde (MDA), a lipid peroxidation biomarker of broad interest. Chapter two describes the study of the effects of the reaction solvent, temperature, acid catalyst, and calibration method on the assay performance. The most rapid MDA assays achieved so far is 3 mins, 30 times more efficient than the current equilibrium spectroscopic quantification.
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In situ infrared spectroscopic studies of electrocatalytic systemsBae, In Tae January 1990 (has links)
No description available.
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New techniques of multiple integral field spectroscopyRen, Deqing January 2001 (has links)
The work of this thesis is to investigate new techniques for Integral Field Spectroscopy (IPS) to make the most efficient use of modem large telescopes. Most of the work described is aimed at the FMOS for the SUBARU 8m telescope. Although this is primarily a system for Multiple Object Spectroscopy (MOS) employing single fibres, there is an option to include a multiple-IFS (MIPS) system. Much of this thesis is therefore aimed at the design and prototyping of critical systems for both the IPS and MOS modes of this instrument. The basic theory of IFU design is discussed first. Some particular problems are described and their soludons presented. The design of the MIPS system is described together with the construction and testing of a prototype deployable IFU. The assembly of the pickoff/fore-optics, microlens array and fibre bundle and their testing are described in detail. The estimated performance of the complete module is presented together with suggestions for improving the system efficiency which is currently limited by the performance of the microlens array. The prototyping of the MIPS system is supported by an extensive programme of testing of candidate microlens arrays. Another critical aspect of the instrument is the ability to disconnect the (IPS and MOS) fibre input which is installed on a removable prime focus top-end ring from the spectrographs which are mounted elsewhere on the telescope. This requires high-performance multiple fibre connectors. The designs of connectors for the MOS and IPS modes are described. Results from the testing of a prototype for the MOS mode are presented. This work is supported by a mathematical model of the coupling efficiency which takes into account optical aberrations and alignment errors. The final critical aspect of FMOS which has been investigated is the design of the spectrographs. The baseline system operates in the near-infrared (NIR) but an additional visible channel is an option. Efficient designs for both the visible and NIR systems are presented. The design of the NIR spectrograph presents challenges in the choice of materials for the doublet and triplet lenses employed. The choice of material and the combinations in which they can be used are described. This thesis shows that all these critical aspects of FMOS have good solutions that will result in good performance of the whole instrument. For the multiple IFU system, the prototype demonstrates acceptable performance which can be made excellent by the use of a better microlens array. The multiple fibre connector prototype already indicates excellent performance. Finally, the spectrograph designs presented should result in high efficiency and good image quality.
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Parallaxes and infrared photometry of three Y0 dwarfsSmart, R. L., Apai, D'aniel, Kirkpatrick, J. Davy, Leggett, S. K., Marocco, F., Morrison, Jane E., Jones, H. R. A., Pinfield, D., Tremblin, P., Amundsen, D. S. 07 1900 (has links)
We have followed up the three Y0 dwarfs WISEPA J041022.71+150248.5, WISEPA J173835.53+273258.9 and WISEPC J205628.90+145953.3 using the United Kingdom Infrared Telescope Wide Field Camera. We find parallaxes that are more consistent and accurate than previously published values. We estimate absolute magnitudes in photometric passbands from Y to W3 and find them to be consistent between the three Y0 dwarfs indicating that the inherent cosmic absolute magnitude spread of these objects is small. We examine the Mauna Kea Observatory system J magnitudes over the 4 yr time line and find small but significant monotonic variations. Finally, we estimate physical parameters from a comparison of spectra and parallax to equilibrium and non-equilibrium models finding values consistent with solar metallicity, an effective temperature of 450-475 K and log g of 4.0-4.5.
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A VERSATILE TECHNIQUE TO ENABLE SUB-MILLI-KELVIN INSTRUMENT STABILITY FOR PRECISE RADIAL VELOCITY MEASUREMENTS: TESTS WITH THE HABITABLE-ZONE PLANET FINDERStefansson, Gudmundur, Hearty, Frederick, Robertson, Paul, Mahadevan, Suvrath, Anderson, Tyler, Levi, Eric, Bender, Chad, Nelson, Matthew, Monson, Andrew, Blank, Basil, Halverson, Samuel, Henderson, Chuck, Ramsey, Lawrence, Roy, Arpita, Schwab, Christian, Terrien, Ryan 16 December 2016 (has links)
Insufficient instrument thermomechanical stability is one of the many roadblocks for achieving 10 cm s(-1) Doppler radial velocity precision, the precision needed to detect Earth-twins orbiting solar-type stars. Highly temperature and pressure stabilized spectrographs allow us to better calibrate out instrumental drifts, thereby helping in distinguishing instrumental noise from astrophysical stellar signals. We present the design and performance of the Environmental Control System (ECS) for the Habitable-zone Planet Finder (HPF), a high-resolution (R = 50,000) fiber-fed near-infrared (NIR) spectrograph for the 10 m Hobby-Eberly Telescope at McDonald Observatory. HPF will operate at 180 K, driven by the choice of an H2RG NIR detector array with a 1.7 mu m cutoff. This ECS has demonstrated 0.6 mK rms stability over 15 days at both 180 and 300 K, and maintained high-quality vacuum (< 10 (7) Torr) over months, during long-term stability tests conducted without a planned passive thermal enclosure surrounding the vacuum chamber. This control scheme is versatile and can be applied as a blueprint to stabilize future NIR and optical high-precision Doppler instruments over a wide temperature range from similar to 77 K to elevated room temperatures. A similar ECS is being implemented to stabilize NEID, the NASA/NSF NN-EXPLORE spectrograph for the 3.5 m WIYN telescope at Kitt Peak, operating at 300 K. A [full SolidWorks 3D-CAD model] and a comprehensive parts list of the HPF ECS are included with this manuscript to facilitate the adaptation of this versatile environmental control scheme in the broader astronomical community.
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DETECTION OF ROTATIONAL SPECTRAL VARIATION ON THE M-TYPE ASTEROID (16) PSYCHESanchez, Juan A., Reddy, Vishnu, Shepard, Michael K., Thomas, Cristina, Cloutis, Edward A., Takir, Driss, Conrad, Albert, Kiddell, Cain, Applin, Daniel 28 December 2016 (has links)
The asteroid (16) Psyche is of scientific interest because it contains similar to 1% of the total mass of the asteroid belt and is thought to be the remnant metallic core of a protoplanet. Radar observations have indicated the significant presence of metal on the surface with a small percentage of silicates. Prior ground-based observations showed rotational variations in the near-infrared (NIR) spectra and radar albedo of this asteroid. However, no comprehensive study that combines multi-wavelength data has been conducted so far. Here we present rotationally resolved NIR spectra (0.7-2.5 mu m) of (16) Psyche obtained with the NASA Infrared Telescope Facility. These data have been combined with shape models of the asteroid for each rotation phase. Spectral band parameters extracted from the NIR spectra show that the pyroxene band center varies from similar to 0.92 to 0.94 mu m. Band center values were used to calculate the pyroxene chemistry of the asteroid, whose average value was found to be Fs(30)En(65)Wo(5). Variations in the band depth (BD) were also observed, with values ranging from 1.0% to 1.5%. Using a new laboratory spectral calibration method, we estimated an average orthopyroxene content of 6% +/- 1%. The mass-deficit region of Psyche, which exhibits the highest radar albedo, also shows the highest value for the spectral slope and the minimum BD. The spectral characteristics of Psyche suggest that its parent body did not have the typical structure expected for a differentiated body or that the sequence of events that led to its current state was more complex than previously thought.
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