High-resolution IR studies of hydrogen bonded clusters: Large amplitude dynamics in (HCl)n

2001 ◽  
Vol 118 ◽  
pp. 63-78 ◽  
Author(s):  
Michal Fárník ◽  
Scott Davis ◽  
David J. Nesbitt
Keyword(s):  
High Resolution ◽  
Large Amplitude ◽  
Ir Studies ◽  
Hydrogen Bonded

scholarly journals Exploring the robustness of Keplerian signals to the removal of active and telluric features

2020 ◽  
Vol 500 (1) ◽  
pp. 548-557
Author(s):  
M Lisogorskyi ◽  
H R A Jones ◽  
F Feng ◽  
R P Butler ◽  
S Vogt
Keyword(s):  
Monte Carlo ◽  
High Resolution ◽  
Monte Carlo Simulations ◽  
Large Amplitude ◽  
Absorption Cell ◽  
Stellar Rotation ◽  
Long Period ◽  
Active Line ◽  
Low Amplitude ◽  
Rotation Signal

ABSTRACT We examine the influence of activity- and telluric-induced radial velocity (RV) signals on high-resolution spectra taken with an iodine absorption cell. We exclude 2-$\mathring{\rm A}$ spectral chunks containing active and telluric lines based on the well-characterized K1V star α Centauri B and illustrate the method on Epsilon Eridani – an active K2V star with a long-period, low-amplitude planetary signal. After removal of the activity- and telluric-sensitive parts of the spectrum from the RV calculation, the significance of the planetary signal is increased and the stellar rotation signal disappears. In order to assess the robustness of the procedure, we perform Monte Carlo simulations based on removing random chunks of the spectrum. Simulations confirm that the removal of lines impacted by activity and tellurics provides a method for checking the robustness of a given Keplerian signal. We also test the approach on HD 40979, which is an active F8V star with a large-amplitude planetary signal. Our Monte Carlo simulations reveal that the significance of the Keplerian signal in the F star is much more sensitive to wavelength. Unlike the K star, the removal of active lines from the F star greatly reduces the RV precision. In this case, our removal of a K star active line from an F star does not a provide a simple useful diagnostic because it has far less RV information and heavily relies on the strong active lines.

scholarly journals Wave Structure within HI Filaments at High Galactic Latitude and the Nature of “Clouds” in Interstellar Space

1991 ◽  
Vol 144 ◽  
pp. 93-96
Author(s):  
Gerrit L. Verschuur
Keyword(s):  
High Resolution ◽  
High Latitude ◽  
High Velocity ◽  
Large Amplitude ◽  
Wave Structure ◽  
Interstellar Space ◽  
Galactic Latitude ◽  
High Galactic Latitude ◽  
Field Geometry ◽  
High Velocity Clouds

Large amplitude waves have been found in the morphology and velocity patterns of several long filaments of HI at high latitude. HI in the filaments is controlled by magnetic fields and the velocity patterns and morphology bear the hallmarks of Alfvén waves. Enhanced emission features (EEFs), traditionally referred to as “clouds,” are seen wherever a segment of flux tube is viewed end-on. This suggests that HI emission structure teaches us about field geometry and not about cloud physics. Similar effects have been recognized in other regions mapped with high-resolution as well as in completely mapped high-velocity “clouds.”

First high resolution analysis of the ν21 band of propane CH3CH2CH3 at 921.382cm−1: Evidence of large amplitude tunneling effects

2015 ◽  
Vol 315 ◽  
pp. 55-62 ◽  
Author(s):  
A. Perrin ◽  
F. Kwabia-Tchana ◽  
J.M. Flaud ◽  
L. Manceron ◽  
J. Demaison ◽  
...  
Keyword(s):  
High Resolution ◽  
Large Amplitude ◽  
High Resolution Analysis ◽  
Resolution Analysis

Design, Synthesis and Characterization of Hydrogen Bonded Binary Liquid Crystal Complex from 4-Methoxycinnamic Acid and 4-Hexyloxybenzoic Acid (4MCA:6OBA)

2017 ◽  
Vol 231 (11-12) ◽  
Author(s):  
Thamilarasan Ranjeeth Kumar ◽  
Sankaran Sundaram ◽  
Thangaiyan Chitravel ◽  
Ramasamy Jayaprakasam ◽  
Vellalapalayam Nallagounder Vijayakumar
Keyword(s):  
Liquid Crystal ◽  
Binary Mixture ◽  
Tilt Angle ◽  
Phase Variation ◽  
Optical Microscope ◽  
Scanning Calorimetry ◽  
Smectic C ◽  
Ir Studies ◽  
Methoxycinnamic Acid ◽  
Hydrogen Bonded

AbstractHydrogen bonded liquid crystal (HBLC) binary mixture has been synthesized from mesogenic 4-methoxycinnamic acid (4MCA) and mesogenic 4-hexyloxybenzoic acid (6OBA) with different mole ratio. The mesomorphic phase behavior and corresponding phase transition temperatures along with the enthalpy values were investigated by differential scanning calorimetry (DSC). The characteristic textures of 4MCA+6OBA binary mixture were observed by using polarizing optical microscope (POM). Fourier transform infrared spectroscopic (FT-IR) studies confirm the formation of hydrogen bond in the present binary mixture. A note worthy observation in this complex is that pure mesogens have no smectic phase where as 4MCA+6OBA binary mixture exhibits a nematic phase along with higher order smectic C (Sm C) phase. Variation of mole ratio influences thermal properties such as phase peak, enthalpy values and thermal span width of the present HBLC binary mixture complex. The optical tilt angle of 4MCA+6OBA for smectic C phase and thermal stability factors have been investigated. Optical tilt angle for smectic C phase is determined and same is fitted to a power law.

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