Top PDF Rotational spectroscopy and observational astronomy of prebiotic molecules

Rotational spectroscopy and observational astronomy of prebiotic molecules

Rotational spectroscopy and observational astronomy of prebiotic molecules

Thank you to the past and current members of the Blake group. To those who have accompanied me on this incredible journey of the Yellow Submarine–Suzanne Bisschop, Garrett Bittner, Rogier Braakman, Dan Holland, Vadym Kapinus, Matt Kelley, Brian Meehan, and Mike Morton–I am so glad to have had you all as office and lab mates, and I want to thank you for your help and support in getting the Great Yellow Beast up and running. To my SURF students Katie Dyl and Maryam Ali, it was a pleasure to help you get started in your scientific careers; thank you for all of your help and hard work. As for the astronomy side of the group, I would like to thank Adwin Boogert, Suzanne Bisschop, and Rogier Braakman for being great backup observers on those long, long nights atop Mauna Kea, and Karin Oberg for just being a great person. I would especially like to thank Jackie Kessler-Silacci for the many long hours of pouring over equations and observational spectra and her extreme patience as I learned a new field. But I would most notably like to thank Karin, Suzanne, and Jackie for being not only great group members but also true and wonderful friends.
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Time-Domain TeraHertz Spectroscopy and Observational Probes of Prebiotic Interstellar Gas and Ice Chemistry

Time-Domain TeraHertz Spectroscopy and Observational Probes of Prebiotic Interstellar Gas and Ice Chemistry

Understanding the origin of life on Earth has long fascinated the minds of the global community, and has been a driving factor in interdisciplinary research for centuries. Beyond the pioneering work of Darwin, perhaps the most widely known study in the last century is that of Miller & Urey, who examined the possibility of the formation of prebiotic chemical precursors on the primordial Earth [1]. More recent studies have shown that amino acids, the chemical building blocks of the biopolymers that comprise life as we know it on Earth, are present in meteoritic samples, and that the molecules extracted from the meteorites display isotopic signatures indicative of an extraterrestrial origin [2]. The most recent major discovery in this area has been the detection of glycine (NH 2 CH 2 COOH), the simplest amino acid, in pristine cometary samples returned by the NASA STARDUST mission [3]. Indeed, the open questions left by these discoveries, both in the public and scientific communities, hold such fascination that NASA has designated the understanding of our “Cosmic Origins” as a key mission priority.
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Laboratory and Astronomical Rotational Spectroscopy

Laboratory and Astronomical Rotational Spectroscopy

better understand how it is formed. Finally, chapter 6 discusses the non-detection of a third species, ethyl-methyl ether and its implications for chemical complex- ity. All three of these chapters revolve around the central goal of observational astrochemistry: the use of telescopes to measure the composition of the universe. As discussed above, this is frequently using radio to terahertz instruments, broadly referred to as radio astronomy, which almost universally measure rotational transi- tions. There are many important reasons for this. First, the universe is essentially transparent at radio frequencies [111]. This allows the detection of species through- out the interstellar medium (ISM), particularly in dense molecular cores where they are a formed. Second optical and infrared transitions in isolation may be molecule specific, however in the complex mixtures of the ISM, it is impossible to disentangle the mixture of signals found and identify the individual components [3]. Finally, at the temperatures typical of the ISM, molecules are too cold to spontaneously emit at frequencies above a few terahertz, making them impossible to detect unless they have a bright background source behind them, or are detected by direct emission through radio astronomy. There are, of course, many exceptions to this. Indeed, the first molecular detections in the ISM, were done in the optical [2]. More recent detections of H + 3 [101], C + 60 [54], detection of gravitational waves[1], and the contin- uing detection of molecules in exoplanetary atmospheres [94], highlight this fact. Nevertheless, of the nearly 200 molecules detected in the interstellar medium, only a handful have been observed through anything other than radio astronomy.
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GCSE. Astronomy. Edexcel GCSE in Astronomy (2AS01) Specification

GCSE. Astronomy. Edexcel GCSE in Astronomy (2AS01) Specification

Teachers must mark the student’s work using the assessment criteria specified below. Teachers should check carefully that the students’ work is their own and is not copied from source material without any attempt by the students to put the material in their own words. Each observational task (both aided and unaided) should be awarded a mark out of five in each of the design, observation, analysis and evaluation strands.

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A REVIEW: TERAHERTZ SPECTROSCOPY AS A VIABLE DYNAMIC TOOL FOR PROTEIN AND ORGANIC MOLECULES CHARACTERIZATION

A REVIEW: TERAHERTZ SPECTROSCOPY AS A VIABLE DYNAMIC TOOL FOR PROTEIN AND ORGANIC MOLECULES CHARACTERIZATION

ABSTRACT THz spectroscopy is a relatively new spectroscopic method in which the THz useful range of frequencies is from 300 cm-1 down to 3 cm-1, a spectral region unachievable by FTIR spectroscopy. Multiple resonances in the absorption spectra of organic molecules exist in the THz range around 0.1–10 THz (3 to 300 cm-1) where these resonances arise from electromagnetic wave interaction of the THz source with the low-frequency, and hence large- scale, vibrational modes within the organic macromolecules. These major vibrational modes correspond to the quaternary or overall structure of macromolecules. The concerted motion of protein structure can also be investigated by THz spectroscopy, which enables both energy and momentum transfer at the picosecond time scale. The short bursts of far-IR radiation in an ultra-fast time scale in THz spectroscopy al- low researchers to study the dynamic processes of various materials for a large variety of applications. This review paper discusses the probability of utilizing THz spectroscopy as a probe to determine the intermolecular structures
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Using ScalIT for Performing Accurate Rovibrational Spectroscopy Calculations  for Triatomic Molecules: A Practical Guide

Using ScalIT for Performing Accurate Rovibrational Spectroscopy Calculations for Triatomic Molecules: A Practical Guide

This paper presents a practical guide for use of the ScalIT software package to perform highly ac- curate bound rovibrational spectroscopy calculations for triatomic molecules. At its core, ScalIT serves as a massively scalable iterative sparse matrix solver, while assisting modules serve to create rovibrational Hamiltonian matrices, and analyze computed energy levels (eigenvalues) and wavefunctions (eigenvectors). Some of the methods incorporated into the package include: phase space optimized discrete variable representation, preconditioned inexact spectral transform, and optimal separable basis preconditioning. ScalIT has previously been implemented successfully for a wide range of chemical applications, allowing even the most state-of-the-art calculations to be computed with relative ease, across a large number of computational cores, in a short amount of time.
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Microwave and far-infrared spectroscopy of water-containing, hydrogen-bonded dimers : vibrational, rotational, and tunneling dynamics

Microwave and far-infrared spectroscopy of water-containing, hydrogen-bonded dimers : vibrational, rotational, and tunneling dynamics

XVI Abbreviations A-H···B hydrogen bond: A-H =donor and B =acceptor BSSE basis set superposition error CW continuous wave--to refer to any quantity that flows or emits continuously, as o[r]

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Cicero's Astronomy

Cicero's Astronomy

In the D.N.D., astronomy becomes a rhetorical figure, parallel to the celestial globes described at 2.87–8, designed to illustrate the order of the world.33 It can be argued that the see[r]

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ASTRONOMY PROGRAM ASTRONOMY, TECHNOLOGY, INDUSTRY

ASTRONOMY PROGRAM ASTRONOMY, TECHNOLOGY, INDUSTRY

Exceptions are spin-offs developed by Dr. Guzmán and Dr. Guesalaga at Pontificia Universidad Católica de Chile: Astroinventions offers cryogenic cameras, and DESA SA provides electronic control systems and signal processing for the defense sector. Also it was mentioned that individual AIUC members had partnerships with the local wine and mining industry. Universidad de Chile reported to have cooperated with a company for the outsourcing of components. Obstacles for industry collaboration, identified by the universities, include the particularity and complexity of technical requirements that needed to be fulfilled for astroengineering projects. Thus, Universidad de Chile stated to have established joint work between the university’s laboratory team and the company in order to achieve the optimal thickness of a gold layer for a low noise amplifier. Nevertheless, by organizing special topics meeting and symposia, centers of excellence which historically have had more interaction with industry, such as the Center for Mathematical Modeling (CMM) have drawn the attention of international researchers and industry to research and development conducted for astronomy. As CMM states, the Pucón Symposium, organized biannually since 2009 in cooperation with the National Research University Network (REUNA), ALMA, and AURA, and sponsored by CONICYT, has become a successful international conference focused on mathematical and computational tools as well as engineering and technological aspects, attracting the interest of researchers in areas such as astronomy, mining, natural resources, and biosciences. University groups identified the following (unexploited) opportunities for spin-offs and the development or transfer of applications for other industries:
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Astronomy and Music

Astronomy and Music

In conclusion, what does this study of music and astronomy (but honestly, more music than astronomy) tell us? In a way, we’re required first to determine the aim of the music, and what it seeks to accomplish: is the goal to add scientific truth to the realm of fine arts and literature, is it to make music that the listener enjoys, or is it simply a matter of letting out the music when, as Beethoven has been quoted saying, “the spirit moves [you]” (Blum 230)? Perhaps the wordless songs of the old classical ages may be the more potent and culturally effective viaducts to a musical-astronomical bond. But to satisfy both the objectives of musical excellence and scientific propagation, it may be that popular, emotional music, which grows with the zeitgeist, may have the advantage.
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A Scheme for Ultrasensitive Detection of Molecules with Vibrational Spectroscopy in Combination with Signal Processing

A Scheme for Ultrasensitive Detection of Molecules with Vibrational Spectroscopy in Combination with Signal Processing

Abstract: We show that combining vibrational spectroscopy with signal processing can result in a scheme for ultrasensitive detection of molecules. We consider the vibrational spectrum as a signal on the energy axis and apply a matched filter on that axis. On the example of a nerve agent molecule, we show that this allows detecting a molecule by its vibrational spectrum even when the recorded spectrum is completely buried in noise, when conventional spectroscopic detection is impossible. Detection is predicted to be possible with signal-to-noise ratios in recorded spectra as low as 0.1. We study the importance of spectral range used for detection as well as of the quality of the computed spectrum used to program the filter, specifically, the role of anharmonicity, of the exchange correlation functional, and of the basis set. The use of the full spectral range rather than of a narrow spectral window with key vibrations is shown to be advantageous, as well as accounting for anharmonicity.
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Oxidized polyethylene films for orienting polar molecules for linear dichroism spectroscopy

Oxidized polyethylene films for orienting polar molecules for linear dichroism spectroscopy

Ultra-violet absorbance and linear dichroism spectroscopy Ultra-violet absorbance and LD spectra on lms oriented with the stretch direction parallel to the horizontally polarized light were measured using a JASCO J-815 circular dichroism spec- tropolarimeter adapted for LD spectroscopy by collecting LD in one data channel and A in another. In general, baselines were collected on the lms before the addition of the sample. The data acquisition and baseline subtraction were performed using the J-815 Spectra Manager soware version 2.07.02. The spectra of samples (and baselines) were measured as a function of different stretching lengths of polyethylene. If a single lm was measured at different stretch factors, baselines were measured on three independent lms treated in as close to identical fashion as was possible. All measurements for lm-rotation LD were performed using a Bio-Logic MOS-450 spectrometer.
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Obtaining the structure and bond rotational potential of a substituted ethane by NMR spectroscopy of solutions in nematic liquid crystalline solvents

Obtaining the structure and bond rotational potential of a substituted ethane by NMR spectroscopy of solutions in nematic liquid crystalline solvents

ther one or both of these methods of obtaining the structure are in error. Comparisons of these two methods, and also with structures obtained from rotational spectroscopy, are usually within much closer agreement. 20 There are cases, however, involving small molecules, such as methyl fluoride 21 and methyl iodide, 22 when very large, and temperature- and solvent-dependent discrepancies are ob- served. These cases are most probably because of multiple site-specific interactions between the solute and solvent mol- ecules. For rigid molecules this phenomenon is easily iden- tified because of violations of geometrical consistency, but this test is not applicable in the present case. The bond angles derived here from the NMR data are reasonable, being closer to tetrahedral geometry for the two carbon atoms than pre- dicted by the quantum-chemical calculations. However, it will be interesting to use the methodology developed here to investigate whether the derived geometry and the conforma- tional distribution are dependent on the liquid-crystalline sol- vent used, and such studies are in progress.
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The Cost of Astronomy Publishing fees in astronomy: Is something rotten in the case of Denmark?

The Cost of Astronomy Publishing fees in astronomy: Is something rotten in the case of Denmark?

Abstract. Using Scopus and national sources, I have investigated the evolution of the cost of publishing in Danish astronomy on a fine scale over a number of years. I find that the number of publications per year from Danish astronomers increased by a factor of four during 15 years: naturally, the corresponding potential cost of publishing must have in- creased similarly. The actual realized cost of publishing in core journals are investigated for a high profile Danish astronomy research institutions. I argue that the situation is highly unstable if the current cost scenario continues, and I speculate that Danish astron- omy is risking a scholarly communication collapse due to the combination of increasing subscription cost, increased research output, and increased direct publishing costs related to Open Access and other page charges.
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Women in Italian Astronomy

Women in Italian Astronomy

The  Livio  Gratton  Prize  is  awarded  to  the  best  doctoral  dissertation  in  astronomy  in  Italy.  Other  excellent   dissertations  receive  nominations.  The  Livio  Gratton  Prize  has  been  assigned  every  two  years  since  1993  (11   editions).    4  out  of  11  winners  were  women  (see  Figure  4);  9  out  of  22  nominations  were  given  to  women.   Therefore,  about  40%  of  the  best  astronomy  PhD  theses  over  the  last  20  years  in  Italy  were  done  by  women.  
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Statistical Distributions in Astronomy

Statistical Distributions in Astronomy

• X’s are Independent : the outcome of any one experiment does not influence the outcomes of others (random draws). • X’s are Identically Distributed : every X is drawn from the same[r]

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Physics, astronomy and astrophysics

Physics, astronomy and astrophysics

description and modelling of phenomena. The fundamentals, which all students need to cover to some extent, include electromagnetism, quantum and classical mechanics, statistical physics and thermodynamics, wave phenomena and the properties of matter. Students should also study the application of the fundamental principles to particular areas. These may include (but need not be limited to) atomic physics, nuclear and particle physics, condensed matter physics, materials, optics, plasmas, and fluids. Astrophysics and astronomy programmes should normally include the application of physical principles to cosmology; the structure, formation and evolution of stars and galaxies; planetary systems; and high-energy phenomena in the universe. In addition, the curricula should help students to develop some qualitative understanding of current developments at the frontiers of the subject.
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Amateur Astronomy & Telescopes

Amateur Astronomy & Telescopes

𝑀𝑖𝑛𝑖𝑚𝑢𝑚 𝑈𝑠𝑒𝑓𝑢𝑙 𝑀𝑎𝑔𝑛𝑖𝑓𝑖𝑐𝑎𝑡𝑖𝑜𝑛 = 3 × 𝐴𝑝𝑒𝑟𝑡𝑢𝑟𝑒 Minimum magnification is good for viewing large areas of the sky. 𝑳𝒊𝒎𝒊𝒕𝒊𝒏𝒈 𝑴𝒂𝒈𝒏𝒊𝒕𝒖𝒅𝒆 = 𝟐 + 𝟓𝐥𝐨𝐠 𝑨𝒑𝒆𝒓𝒕𝒖𝒓𝒆 Tells you the highest magnitude[r]

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Quintus Cicero's Astronomy?

Quintus Cicero's Astronomy?

Despite limiting its content to the zodiac in his study of our fragment, in a later work Possanza seems to imply that our poem is in some sense a translation of Aratus, asserting that th[r]

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Investigations into cosmology and astronomy

Investigations into cosmology and astronomy

In this analysis, we consider the universe to be filled with non-interacting matter and radiation, and a world-model is defined in a most general way by its density parameter a o and the[r]

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