An Attempt to Detect Rayleigh Scattering in the Atmospheres of Extrasolar Planets Using a Ground-Based Telescope
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Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
12 Light Scattering AQ1
12 Light Scattering AQ1 Lev T. Perelman CONTENTS 12.1 Introduction ......................................................................................................................... 321 12.2 Basic Principles of Light Scattering ....................................................................................323 12.3 Light Scattering Spectroscopy ............................................................................................325 12.4 Early Cancer Detection with Light Scattering Spectroscopy .............................................326 12.5 Confocal Light Absorption and Scattering Spectroscopic Microscopy ............................. 329 12.6 Light Scattering Spectroscopy of Single Nanoparticles ..................................................... 333 12.7 Conclusions ......................................................................................................................... 335 Acknowledgment ........................................................................................................................... 335 References ...................................................................................................................................... 335 12.1 INTRODUCTION Light scattering in biological tissues originates from the tissue inhomogeneities such as cellular organelles, extracellular matrix, blood vessels, etc. This often translates into unique angular, polari- zation, and spectroscopic features of scattered light emerging from tissue and therefore information about tissue -
Arxiv:2008.11688V1 [Astro-Ph.CO] 26 Aug 2020
APS/123-QED Cosmology with Rayleigh Scattering of the Cosmic Microwave Background Benjamin Beringue,1 P. Daniel Meerburg,2 Joel Meyers,3 and Nicholas Battaglia4 1DAMTP, Centre for Mathematical Sciences, Wilberforce Road, Cambridge, UK, CB3 0WA 2Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands 3Department of Physics, Southern Methodist University, 3215 Daniel Ave, Dallas, Texas 75275, USA 4Department of Astronomy, Cornell University, Ithaca, New York, USA (Dated: August 27, 2020) The cosmic microwave background (CMB) has been a treasure trove for cosmology. Over the next decade, current and planned CMB experiments are expected to exhaust nearly all primary CMB information. To further constrain cosmological models, there is a great benefit to measuring signals beyond the primary modes. Rayleigh scattering of the CMB is one source of additional cosmological information. It is caused by the additional scattering of CMB photons by neutral species formed during recombination and exhibits a strong and unique frequency scaling ( ν4). We will show that with sufficient sensitivity across frequency channels, the Rayleigh scattering/ signal should not only be detectable but can significantly improve constraining power for cosmological parameters, with limited or no additional modifications to planned experiments. We will provide heuristic explanations for why certain cosmological parameters benefit from measurement of the Rayleigh scattering signal, and confirm these intuitions using the Fisher formalism. In particular, observation of Rayleigh scattering P allows significant improvements on measurements of Neff and mν . PACS numbers: Valid PACS appear here I. INTRODUCTION direction of propagation of the (primary) CMB photons. There are various distinguishable ways that cosmic In the current era of precision cosmology, the Cosmic structures can alter the properties of CMB photons [10]. -
On the Detection of Exoplanets Via Radial Velocity Doppler Spectroscopy
The Downtown Review Volume 1 Issue 1 Article 6 January 2015 On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy Joseph P. Glaser Cleveland State University Follow this and additional works at: https://engagedscholarship.csuohio.edu/tdr Part of the Astrophysics and Astronomy Commons How does access to this work benefit ou?y Let us know! Recommended Citation Glaser, Joseph P.. "On the Detection of Exoplanets via Radial Velocity Doppler Spectroscopy." The Downtown Review. Vol. 1. Iss. 1 (2015) . Available at: https://engagedscholarship.csuohio.edu/tdr/vol1/iss1/6 This Article is brought to you for free and open access by the Student Scholarship at EngagedScholarship@CSU. It has been accepted for inclusion in The Downtown Review by an authorized editor of EngagedScholarship@CSU. For more information, please contact [email protected]. Glaser: Detection of Exoplanets 1 Introduction to Exoplanets For centuries, some of humanity’s greatest minds have pondered over the possibility of other worlds orbiting the uncountable number of stars that exist in the visible universe. The seeds for eventual scientific speculation on the possibility of these "exoplanets" began with the works of a 16th century philosopher, Giordano Bruno. In his modernly celebrated work, On the Infinite Universe & Worlds, Bruno states: "This space we declare to be infinite (...) In it are an infinity of worlds of the same kind as our own." By the time of the European Scientific Revolution, Isaac Newton grew fond of the idea and wrote in his Principia: "If the fixed stars are the centers of similar systems [when compared to the solar system], they will all be constructed according to a similar design and subject to the dominion of One." Due to limitations on observational equipment, the field of exoplanetary systems existed primarily in theory until the late 1980s. -
List of Easy Double Stars for Winter and Spring = Easy = Not Too Difficult = Difficult but Possible
List of Easy Double Stars for Winter and Spring = easy = not too difficult = difficult but possible 1. Sigma Cassiopeiae (STF 3049). 23 hr 59.0 min +55 deg 45 min This system is tight but very beautiful. Use a high magnification (150x or more). Primary: 5.2, yellow or white Seconary: 7.2 (3.0″), blue 2. Eta Cassiopeiae (Achird, STF 60). 00 hr 49.1 min +57 deg 49 min This is a multiple system with many stars, but I will restrict myself to the brightest one here. Primary: 3.5, yellow. Secondary: 7.4 (13.2″), purple or brown 3. 65 Piscium (STF 61). 00 hr 49.9 min +27 deg 43 min Primary: 6.3, yellow Secondary: 6.3 (4.1″), yellow 4. Psi-1 Piscium (STF 88). 01 hr 05.7 min +21 deg 28 min This double forms a T-shaped asterism with Psi-2, Psi-3 and Chi Piscium. Psi-1 is the uppermost of the four. Primary: 5.3, yellow or white Secondary: 5.5 (29.7), yellow or white 5. Zeta Piscium (STF 100). 01 hr 13.7 min +07 deg 35 min Primary: 5.2, white or yellow Secondary: 6.3, white or lilac (or blue) 6. Gamma Arietis (Mesarthim, STF 180). 01 hr 53.5 min +19 deg 18 min “The Ram’s Eyes” Primary: 4.5, white Secondary: 4.6 (7.5″), white 7. Lambda Arietis (H 5 12). 01 hr 57.9 min +23 deg 36 min Primary: 4.8, white or yellow Secondary: 6.7 (37.1″), silver-white or blue 8. -
Chapter 1 a Theoretical and Observational Overview of Brown
Chapter 1 A theoretical and observational overview of brown dwarfs Stars are large spheres of gas composed of 73 % of hydrogen in mass, 25 % of helium, and about 2 % of metals, elements with atomic number larger than two like oxygen, nitrogen, carbon or iron. The core temperature and pressure are high enough to convert hydrogen into helium by the proton-proton cycle of nuclear reaction yielding sufficient energy to prevent the star from gravitational collapse. The increased number of helium atoms yields a decrease of the central pressure and temperature. The inner region is thus compressed under the gravitational pressure which dominates the nuclear pressure. This increase in density generates higher temperatures, making nuclear reactions more efficient. The consequence of this feedback cycle is that a star such as the Sun spend most of its lifetime on the main-sequence. The most important parameter of a star is its mass because it determines its luminosity, ef- fective temperature, radius, and lifetime. The distribution of stars with mass, known as the Initial Mass Function (hereafter IMF), is therefore of prime importance to understand star formation pro- cesses, including the conversion of interstellar matter into stars and back again. A major issue regarding the IMF concerns its universality, i.e. whether the IMF is constant in time, place, and metallicity. When a solar-metallicity star reaches a mass below 0.072 M ¡ (Baraffe et al. 1998), the core temperature and pressure are too low to burn hydrogen stably. Objects below this mass were originally termed “black dwarfs” because the low-luminosity would hamper their detection (Ku- mar 1963). -
Rayleigh Scattering by Gas Molecules: Why Is the Sky Blue?
Please do not remove this manual from from the lab. It is available via Canvas DEMO NOTES: This manual contains demonstrator notes in blue italics Optics Rayleigh Scattering: 12 hrs Rayleigh scattering by gas molecules: why is the sky blue? Objectives After completing this experiment: • You will be familiar with using a photomultiplier tube) as a means of measuring low intensities of light; • You will have had experience of working safely with a medium power laser producing visible wavelength radiation; • You will have had an opportunity to use the concept of solid angle in connection with scattering experiments; • You will have had the opportunity to experimentally examine the phenomenon of polarization; • You should understand how the scattering of light from molecules varies accord- ing to the direction of polarization of the light and the scattering angle relative to it; • You should have a good understanding of what is meant by cross-section and differential cross section. • You should be able to describe why the daytime sky appears to be blue and why light from the sky is polarized. Note the total time for data-taking in this experiment is about one hour. There are a lot of useful physics concepts to absorb in the background material. You should read the manual bearing in mind that you need to thoroughly understand how you will calculate your results from you measurements BEFORE your final lab session. This is an exercise in time management. Safety A medium power Argon ion laser is used in this experiment. The light from it is potentially dangerous to you and other people in the room. -
A Study on Numerical Integration Methods for Rendering Atmospheric
Open Phys. 2019; 17:241–249 Research Article Tomasz Gałaj and Adam Wojciechowski A study on numerical integration methods for rendering atmospheric scattering phenomenon https://doi.org/10.1515/phys-2019-0025 In this paper, a qualitative comparison of three, pop- Received Jan 29, 2019; accepted Mar 07, 2019 ular numerical integration methods to compute the sin- gle scattering integral is presented. In provided research, Abstract: A qualitative comparison of three, popular and three methods have been chosen, namely Midpoint, Trape- most widely known numerical integration methods in zoidal and Simpson’s Rules. These three methods are fairly terms of atmospheric single scattering calculations is pre- popular in Computer Graphics field. Atmospheric scatter- sented. A comparison of Midpoint, Trapezoidal and Simp- ing is calculated using backward ray tracing algorithm tak- son’s Rules taking into account quality of a clear sky gener- ing into account variable light conditions [5]. Then, these ated images is performed. Methods that compute the atmo- methods are compared with each other taking into account spheric scattering integrals use Trapezoidal Rule. Authors quality of the generated images of the sky. As a subproduct try to determine which numerical integration method is of this research, the fidelity of the framework presented the best for determining the colors of the sky and check by Bruneton in [3] is being checked. Authors try to deter- if Trapezoidal Rule is in fact the best choice. The research mine which numerical integration method is the best for does not only conduct experiments with Bruneton’s frame- calculating the colors of the sky and check if Trapezoidal work but also checks which of the selected numerical inte- Rule is in fact the best choice. -
The CORALIE Survey for Southern Extrasolar Planets XVII
Astronomy & Astrophysics manuscript no. coralieXVII c ESO 2019 July 1, 2019 The CORALIE survey for southern extrasolar planets XVII. New and updated long period and massive planets ? ?? M. Marmier1, D. Segransan´ 1, S. Udry1, M. Mayor1, F. Pepe1, D. Queloz1, C. Lovis1, D. Naef1, N.C. Santos2;3;1, R. Alonso4;5;1, S. Alves8;1, S. Berthet1, B. Chazelas1, B-O. Demory9;1, X. Dumusque1, A. Eggenberger1, P. Figueira2;1, M. Gillon6;1, J. Hagelberg1, M. Lendl1, R. A. Mardling7;1, D. Megevand´ 1, M. Neveu1, J. Sahlmann1, D. Sosnowska1, M. Tewes10, and A. H.M.J. Triaud1 1 Observatoire astronomique de l’Universite´ de Geneve,` 51 ch. des Maillettes - Sauverny -, CH-1290 Versoix, Switzerland 2 Centro de Astrof´ısica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal 3 Departamento de F´ısica e Astronomia, Faculdade de Ciencias,ˆ Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal 4 Instituto de Astrof´ısica de Canarias, C/ V´ıa Lactea´ S/N, E-38200 La Laguna, Spain 5 Departamento de Astrof´ısica, Universidad de La Laguna, E-38205 La Laguna, Spain 6 Universite´ de Liege,` Allee´ du 6 aoutˆ 17, Sart Tilman, Liege` 1, Belgium 7 School of Mathematical Sciences, Monash University, Victoria, 3800, Australia 8 Departamento de F´ısica, Universidade Federal do Rio Grande do Norte, 59072-970, Natal, RN., Brazil 9 Department of Earth, Atmospheric and Planetary Sciences, Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA 10 Laboratoire d’astrophysique, Ecole Polytechnique Fed´ erale´ de Lausanne (EPFL), Observatoire de Sauverny, CH-1290 Versoix, Switzerland Received month day, year; accepted month day, year ABSTRACT Context. -
The Evening Sky Map
I N E D R I A C A S T N E O D I T A C L E O R N I G D S T S H A E P H M O O R C I . Z N O p l f e i n h d o P t O o N ) l h a r g Z i u s , o I l C t P h R I r e o R N ( O o r C r H e t L p h p E E i s t D H a ( r g T F i . O B NORTH D R e N M h t E A X O e s A H U M C T . I P N S L E E P Z “ E A N H O NORTHERN HEMISPHERE M T R T Y N H E ” K E η ) W S . T T E W U B R N W D E T T W T H h A The Evening Sky Map e MAY 2021 E . C ) Cluster O N FREE* EACH MONTH FOR YOU TO EXPLORE, LEARN & ENJOY THE NIGHT SKY r S L a o K e Double r Y E t B h R M t e PERSEUS A a A r CASSIOPEIA n e S SKY MAP SHOWS HOW Get Sky Calendar on Twitter P δ r T C G C A CEPHEUS r E o R e J s O h Sky Calendar – May 2021 http://twitter.com/skymaps M39 s B THE NIGHT SKY LOOKS T U ( O i N s r L D o a j A NE I I a μ p T EARLY MAY PM T 10 r 61 M S o S 3 Last Quarter Moon at 19:51 UT. -
Scattering and Polarization
Scattering and Polarization C HAP T E R 13 13.1 these two molecules interferes de 1 3.2 INTRODUCTION structively. as in Figure 12.4 (along RAYLEIGH SCATTERING the x-axis). and this Is so for any - sideways direction from which you - So far we have considered what look at the beam. Air. on the other When white light scatters from hap pens when light encounters ma hand, is a gas. so there is no guar some molecules. it scatters selec terial obstacles of a size much antee that there will be another tively because part of the light is ab greater than the wavelength (geo molecule half a wavelength beyond sorbed at the resonant frequ encies metrical optics) or of a size so small the first-sometimes there may be a of the molecules-the scattered as to be comparable with the wave few extra molecules around one light Is then colored. For man y length of light (wave optics). But point, sometimes a few less. You see other molecules. however, the im you can also observe effects due the scattering from these pOints be portant resonant frequenCies are to even smaller obstacles, much cause of these fluctuations. (The significantly higher than visible fre smaller than the wavelength of visi TRY IT suggests ways to enhance quencies. White light nevertheless ble light. When light interacts with the scattering in air.) becomes colored when it scatters an isolated object that small, it Scattering is selective in several from these molecules-the higher shakes all the charges in the object, ways: light of certain wavelengths the frequency of the incident light. -
EMR's Interaction with the Earth & Atmosphere ∝ ∝ ∝
EMR’s interaction with the earth & atmosphere HANDOUT’s OBJECTIVES: • familiarize student with EMR scattering basics in environment • develop basic principles of radiative transfer in environment • develop Lambert’s law & Schwarzschild equation, plus introduce remote-sensing applications of same Lord Rayleigh & sky blueness “Why is the sky blue?” is a good (and hardly trivial) starting point for studying EMR’s interactions with the earth’s atmosphere and oceans. Water (whether vapor or liquid) is often invoked to explain sky blueness. After all, if ocean water is blue, shouldn’t that explain the sky’s color? Unfortunately, several meters of liquid water are required for water’s blue-green absorption minimum to be visible. If we condensed all atmospheric water vapor into a uniform shell around the earth, the shell would only be a few centimeters thick. Visible scattering by water molecules differs little from that of other atmospheric gases. (At the molecular level, we distinguish between the scattering, or redirecting, of EMR and its absorption, or conversion to other wavelengths (or kinds) of energy.) We retrace the ideas of 19th-century British scientist Lord Rayleigh, who showed that atmospheric molecules themselves are responsible for clear-sky color. Rayleigh Rp reasoned that if a spherical particle’s radius Rp << than that of λlight ( < 0.1, the λlight Rayleigh scattering criterion) its total scattering is ∝ its volume V. So when an EMR wave “illuminates” a molecule, scattering by its atoms is in phase because they are within λlight of each other. Thus the amplitude of the scattered electric field Es ∝ V. Clearly Es also depends on the strength of the incident electric field Ei.