DOCSLIB.ORG

The Search for Dark Matter in Xenon: Innovative Calibration Strategies and Novel Search Channels Shayne Edward Reichard Purdue University

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Search for Dark Matter in Xenon: Innovative Calibration Strategies and Novel Search Channels Shayne Edward Reichard Purdue University Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations 12-2016 The search for dark matter in xenon: Innovative calibration strategies and novel search channels Shayne Edward Reichard Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Physics Commons Recommended Citation Reichard, Shayne Edward, "The es arch for dark matter in xenon: Innovative calibration strategies and novel search channels" (2016). Open Access Dissertations. 994. https://docs.lib.purdue.edu/open_access_dissertations/994 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Graduate School Form 30 Updated PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance This is to certify that the thesis/dissertation prepared By Shayne Edward Reichard Entitled THE SEARCH FOR DARK MATTER IN XENON: INNOVATIVE CALIBRATION STRATEGIES AND NOVEL SEARCH CHANNELS For the degree of Doctor of Philosophy Is approved by the final examining committee: Rafael F. Lang Chair Dimitrios Giannios Matthew Jones Matthew L. Lister To the best of my knowledge and as understood by the student in the Thesis/Dissertation Agreement, Publication Delay, and Certification Disclaimer (Graduate School Form 32), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy of Integrity in Research” and the use of copyright material. Approved by Major Professor(s): Rafael F. Lang Approved by: John P. Finley 11/21/2016 Head of the Departmental Graduate Program Date THE SEARCH FOR DARK MATTER IN XENON: INNOVATIVE CALIBRATION STRATEGIES AND NOVEL SEARCH CHANNELS A Dissertation Submitted to the Faculty of Purdue University by Shayne Edward Reichard In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2016 Purdue University West Lafayette, Indiana ii TABLE OF CONTENTS Page LIST OF TABLES ::::::::::::::::::::::::::::::::: v LIST OF FIGURES :::::::::::::::::::::::::::::::: vii ABSTRACT :::::::::::::::::::::::::::::::::::: xiv 1 DARK MATTER :::::::::::::::::::::::::::::::: 1 1.1 The Friedmann Equation ::::::::::::::::::::::::: 2 1.2 Big Bang Nucleosynthesis :::::::::::::::::::::::: 6 1.3 The Cosmic Microwave Background ::::::::::::::::::: 9 1.3.1 The Curvature of the Universe :::::::::::::::::: 13 1.3.2 Baryon Density :::::::::::::::::::::::::: 13 1.3.3 Dark Matter Density ::::::::::::::::::::::: 13 1.4 Galaxies :::::::::::::::::::::::::::::::::: 14 1.4.1 Milky Way Galaxy :::::::::::::::::::::::: 14 1.4.2 Other Spiral Galaxies ::::::::::::::::::::::: 15 1.4.3 Elliptical Galaxies :::::::::::::::::::::::: 16 1.5 Galaxy Clusters :::::::::::::::::::::::::::::: 17 1.5.1 Orbits of Galaxies ::::::::::::::::::::::::: 18 1.5.2 Hot Gas :::::::::::::::::::::::::::::: 18 1.5.3 Gravitational Lensing ::::::::::::::::::::::: 19 1.6 Structure Formation ::::::::::::::::::::::::::: 21 1.7 Large-Scale Structures :::::::::::::::::::::::::: 23 1.8 Dark Matter Candidates ::::::::::::::::::::::::: 25 1.8.1 Weakly Interacting Massive Particle ::::::::::::::: 26 1.8.2 Axion ::::::::::::::::::::::::::::::: 28 2 DETECTION OF DARK MATTER ::::::::::::::::::::: 31 2.1 Collider Experiments ::::::::::::::::::::::::::: 31 2.2 Indirect Detection ::::::::::::::::::::::::::::: 33 2.3 Direct Detection ::::::::::::::::::::::::::::: 34 2.3.1 Differential Energy Spectrum :::::::::::::::::: 35 2.3.2 Dark Matter Halo Density :::::::::::::::::::: 36 2.3.3 Velocity Distribution ::::::::::::::::::::::: 37 2.3.4 Nuclear Form Factor ::::::::::::::::::::::: 38 2.3.5 Interaction Factor ::::::::::::::::::::::::: 41 2.3.6 Energy Detection Efficiency ::::::::::::::::::: 42 iii Page 2.3.7 Energy Resolution and Threshold :::::::::::::::: 43 2.3.8 Target Mass Fraction ::::::::::::::::::::::: 44 2.3.9 Annual Modulation :::::::::::::::::::::::: 44 2.3.10 WIMP Event Rate :::::::::::::::::::::::: 45 2.4 Low-Background Requirements ::::::::::::::::::::: 48 3 SCATTERING EXPERIMENTS ::::::::::::::::::::::: 51 3.1 Liquid Noble Element Detectors ::::::::::::::::::::: 52 3.1.1 WIMP Recoil Sensitivity ::::::::::::::::::::: 52 3.1.2 Scintillation Signal :::::::::::::::::::::::: 53 3.1.3 Ionization Signal ::::::::::::::::::::::::: 55 3.1.4 Electroluminescence ::::::::::::::::::::::: 56 3.1.5 Radiopurity :::::::::::::::::::::::::::: 57 3.1.6 Self-Shielding ::::::::::::::::::::::::::: 57 3.1.7 Scalability ::::::::::::::::::::::::::::: 59 3.1.8 Discrimination :::::::::::::::::::::::::: 59 3.2 Cryogenic Detectors ::::::::::::::::::::::::::: 60 3.2.1 Low-Temperature Phonon Signal :::::::::::::::: 60 3.2.2 Ionization Collection ::::::::::::::::::::::: 62 3.3 Solid Scintillators ::::::::::::::::::::::::::::: 63 4 XENON ::::::::::::::::::::::::::::::::::::: 65 4.1 The Principle of a Dual-Phase Time Projection Chamber ::::::: 65 4.2 Calibration :::::::::::::::::::::::::::::::: 67 4.3 Light Collection Efficiency :::::::::::::::::::::::: 68 4.4 Energy Scales ::::::::::::::::::::::::::::::: 70 4.4.1 Electronic Recoil Equivalent Energy ::::::::::::::: 70 4.4.2 Nuclear Recoil Equivalent Energy :::::::::::::::: 70 4.4.3 Combined Energy Scale ::::::::::::::::::::: 71 5 RESULTS FROM A CALIBRATION OF XENON100 USING A DISSOLVED RADON-220 SOURCE ::::::::::::::::::::::::::::: 73 5.1 The XENON100 Detector in Run 14 :::::::::::::::::: 74 5.2 220Rn Decay Chain and Observed Time Evolution ::::::::::: 75 5.3 Contamination from the Veto :::::::::::::::::::::: 78 5.4 Combined Leakage Rate ::::::::::::::::::::::::: 80 5.5 Alpha Spectroscopy :::::::::::::::::::::::::::: 81 5.6 220Rn-216Po Coincidence and Convection :::::::::::::::: 83 5.7 The half-life of 212Po ::::::::::::::::::::::::::: 87 5.8 Low-Energy Calibration ::::::::::::::::::::::::: 90 5.9 Conclusions :::::::::::::::::::::::::::::::: 94 6 DARK MATTER SCATTERING INELASTICALLY OFF XENON NUCLEI 95 6.1 Nuclear Structure and WIMP-Nucleon Currents :::::::::::: 96 iv Page 6.2 Structure Factors ::::::::::::::::::::::::::::: 97 6.3 Kinematics of Inelastic Scattering :::::::::::::::::::: 102 6.4 Signatures of Inelastic Dark Matter Scattering ::::::::::::: 105 6.5 Implications for Dark Matter Searches ::::::::::::::::: 111 6.6 Conclusions :::::::::::::::::::::::::::::::: 114 7 SUPERNOVA NEUTRINO PHYSICS WITH XENON DARK MATTER DE- TECTORS: A TIMELY PERSPECTIVE ::::::::::::::::::: 115 7.1 Supernova Neutrino Emission :::::::::::::::::::::: 117 7.1.1 Supernova Neutrino Emission Properties :::::::::::: 118 7.1.2 Neutrino Flavor Conversion ::::::::::::::::::: 121 7.2 Supernova Neutrino Scattering with Dual-Phase Xenon Detectors :: 122 7.2.1 Scattering Rates in Terms of Recoil Energy :::::::::: 124 7.2.2 Generation of the Observable S1 and S2 Signals :::::::: 127 7.2.3 Observable Scattering Rates :::::::::::::::::: 130 7.3 S2-Only Analysis ::::::::::::::::::::::::::::: 133 7.4 Supernova Neutrino Detection :::::::::::::::::::::: 135 7.4.1 Detection Significance :::::::::::::::::::::: 136 7.4.2 Distinguishing Between Supernova Progenitors ::::::::: 138 7.4.3 Reconstructing the Supernova Neutrino Light Curve :::::: 138 7.4.4 Neutrino Differential Flux :::::::::::::::::::: 141 7.4.5 Total Energy Emitted into Neutrinos :::::::::::::: 144 7.4.6 Comparison with Dedicated Neutrino Detectors :::::::: 147 7.4.7 SNEWS & False Alarms ::::::::::::::::::::: 148 7.5 Experimental Factors ::::::::::::::::::::::::::: 150 7.5.1 Signal Uncertainty from Qy ::::::::::::::::::: 150 7.5.2 Sources of Increased Background Rates ::::::::::::: 153 7.5.3 Sensitivity Limitation from Event Pile-Up ::::::::::: 154 7.6 Conclusions :::::::::::::::::::::::::::::::: 155 A Calculations of Velocity Distribution ::::::::::::::::::::: 159 B Calculations of Event Rates :::::::::::::::::::::::::: 161 C Convection Parameter ::::::::::::::::::::::::::::: 163 LIST OF REFERENCES ::::::::::::::::::::::::::::: 165 VITA :::::::::::::::::::::::::::::::::::::::: 180 v LIST OF TABLES Table Page 5.1 The results of a GEANT4 Monte Carlo simulation of leakage events from long-lived isotopes in the veto (buffer) region. The intensities, deposition probabilities, and overall contribution per mille are given for each gamma. The values correspond to the entire active region. :::::::::::: 79 5.2 The total leakage contribution from 208Tl is determined according to the different combinations of de-excitation gammas. The intensities, deposition probabilities, and overall contribution per mille are given for each decay path. The final leakage value accounts for the 36% branching of 208Tl. :: 79 5.3 Q-values, scintillation values (means and widths at 400 V=cm), and calcu- lated light yields of each alpha decay in Figure 5.4. :::::::::::: 83 5.4 The results of a GEANT4 Monte Carlo simulation of leakage events from long-lived isotopes in the veto (buffer) region. The intensities, deposition probabilities, and overall contribution per mille are given for each gamma. The values correspond to the entire active region. :::::::::::: 93 5.5 The total leakage contribution from 208Tl is determined according to the different combinations of de-excitation gammas. The intensities, deposition probabilities, and overall contribution per mille are given for each decay path. The final leakage value accounts for the 36% branching of 208Tl. : 93 6.1 Minimal and maximal recoil energies, in keV, between which inelastic scat- tering is allowed (see Eq. (6.13)) for the two xenon isotopes and various WIMP masses. :::::::::::::::::::::::::::::::: 103 6.2 Minimum energy Evis in keV above
Load more

Recommended publications
  • Arxiv:1306.3244V2 [Astro-Ph.CO] 4 Feb 2014
    The Scientific Reach of Multi-Ton Scale Dark Matter Direct Detection Experiments Jayden L. Newsteada, Thomas D. Jacquesa, Lawrence M. Kraussa;b, James B. Dentc, and Francesc Ferrerd a Department of Physics and School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, USA, b Research School of Astronomy and Astrophysics, Mt. Stromlo Observatory, Australian National University, Canberra 2614, Australia, c Department of Physics, University of Louisiana at Lafayette, Lafayette, LA 70504, USA, and d Physics Department and McDonnell Center for the Space Sciences, Washington University, St Louis, MO 63130, USA (Dated: November 6, 2018) Abstract The next generation of large scale WIMP direct detection experiments have the potential to go beyond the discovery phase and reveal detailed information about both the particle physics and astrophysics of dark matter. We report here on early results arising from the development of a detailed numerical code modeling the proposed DARWIN detector, involving both liquid argon and xenon targets. We incorporate realistic detector physics, particle physics and astrophysical uncertainties and demonstrate to what extent two targets with similar sensitivities can remove various degeneracies and allow a determination of dark matter cross sections and masses while also probing rough aspects of the dark matter phase space distribution. We find that, even assuming arXiv:1306.3244v2 [astro-ph.CO] 4 Feb 2014 dominance of spin-independent scattering, multi-ton scale experiments still have degeneracies that depend sensitively on the dark matter mass, and on the possibility of isospin violation and inelas- ticity in interactions. We find that these experiments are best able to discriminate dark matter properties for dark matter masses less than around 200 GeV.
    [Show full text]
  • The Boundary of Galaxy Clusters and Its Implications on SFR Quenching
    The splashback boundary of galaxy clusters in mass and light and its implications for galaxy evolution T.-H. Shin, Ph.D. candidate at UPenn Collaborators: S. Adhikari, E. J. Baxter, C. Chang, B. Jain, N. Battaglia et al. (DES collaboration) (SPT collaboration) (ACT collaboration) https://arxiv.org/abs/1811.06081 (accepted to MNRAS); 2019 paper in preparation Based on ~400 public cluster sample from ACT+SPT Ongoing analysis of 1000+ SZ-selected clusters from DES+ACT+SPT Background Mass and boundary of dark matter halos However, MΔ and RΔ are subject to pseudo-evolution due to the decrease in the ρ ρ reference density ( c or m) Haloes continuously accrete matter; there is no radius within which the matter is fully virialized ⇒ where is the physical boundary of the halos? Credit: Andrey Kravtsov Cosmology with galaxy clusters Galaxy clusters live in the high-mass tail of the halo mass function ⇒ very sensitive to the growth of the structure Ω σ ( m and 8) Thus, it is important to accurately define/measure Tinker et al. (2008) the mass of the cluster Preliminary work by Diemer et al. illuminates that the mass function becomes more universal against redshift when we use so-called “splashback radius” as the physical boundary of the dark matter halos Background ● Galaxies fall into the cluster potential, escaping from the Hubble flow ● They form a sharp “physical” boundary around their first apocenters after the infall, which we call “splashback radius” Background ● A simple spherical collapse model can predict the existence of the splashback feature (Gunn & Gott 1972, Fillmore & Goldreich 1984, Bertschinger 1985, Adhikari et al.
    [Show full text]
  • Dark Matter 18Th May 2021.Pdf
    Searches for Dark Matter Seminar presentation 18th May 2021 Iida Kostamo 1/20 Contents • Background and history - How did we end up with the dark matter hypothesis? • Hot and cold dark matter - Candidates for cold dark matter • The halo density profile • Simulations (Millennium and Bolshoi) • Summary Seminar presentation 18th May 2021 Iida Kostamo 2/20 Background • The total mass-energy density of the universe (approximately): 1. 5% ordinary baryonic matter 2. 25% dark matter 3. 70% dark energy • Originally dark matter was referred to as "the missing mass" - 1930's: Fritz Zwicky did research on galaxy clusters • ...The problem is the missing light, not the missing mass, hence "dark matter" Seminar presentation 18th May 2021 Iida Kostamo 3/20 The rotation curves of galaxies • The rotation curve describes how the rotation velocity of an object depends on the distance from the center of the galaxy • Assumption: Kepler's III law, i.e. the rotation velocities decrease with increasing distance • In the 1970's Vera Rubin and her colleagues did research on the rotation curves of various spiral galaxies Seminar presentation 18th May 2021 Iida Kostamo 4/20 The rotation curves of galaxies • H = Hubble constant • The rotation curves become flat when the radius is large enough • The same result for all galaxies: the rotation curves are not descending → There must be non-luminous mass in galaxies Seminar presentation 18th May 2021 Iida Kostamo 5/20 MACHOs (Massive Astrophysical Compact Halo Object) • Objects that emit extremely little or no light →
    [Show full text]
  • On Problems Related to Galaxy Formation
    On Problems Related To Galaxy Formation Dissertation zur Erlangung des Doktorgrades (Dr. rer. nat.) der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn vorgelegt von Ahmed Hasan Abdullah aus Baghdad Bonn 2016 Angefertigt mit Genehmigung der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn 1. Gutachter: Prof. Dr. P. Kroupa 2. Gutachterin: Dr. Maria Massi Tag der Promotion: 11.04.2016 Erscheinungsjahr: 2016 To My Parents i Erklärung Hiermit versichere ich, die vorgelegte Arbeit - abgesehen von den ausdrücklich angegebenen Hilfsmit- teln -persönlich, selbstständig und ohne die Benutzung anderer als der angegebenen Hilfsmittel angefer- tigt zu haben. Die aus anderen Quellen direkt und indirekt verwendeten Daten und Konzepte sind unter der Angabe der Quelle kenntlich gemacht. Weder die vorgelegte Arbeit noch eine ähnliche Arbeit sind bereits anderweitig als Dissertation eingereicht worden und von mir wurden zuvor keine Promotionsver- suche unternommen. Für die Erstellung der vorgelegten Arbeit wurde keine fremde Hilfe, insbesondere keine entgeltliche Hilfe von Vermittlungs-, Beratungsdiensten oder Ähnlichem, in Anspruch genom- men. Bonn, den Ahmed Abdullah iii Acknowledgements I owe thanks to many people for their support and guidance which gave me a chance to complete this thesis. I am truly indebted and thankful for their support. First and foremost, I would like to express my deep and sincere gratitude to my advisor, Prof. Dr. Pavel Kroupa, for the continuous support of my study and research, and his motivation, encouragement and patient supervision. It was an honor to have a supervisor who was so patient and willing to help . I would also like to express my gratitude to Dr.
    [Show full text]
  • An Astronomy Ubd for 8Th Grade Miguel Angel Webber [email protected]
    Trinity University Digital Commons @ Trinity Understanding by Design: Complete Collection Understanding by Design 6-2019 Looking Up! What is our place in the universe? - An Astronomy UbD for 8th Grade Miguel Angel Webber [email protected] Follow this and additional works at: https://digitalcommons.trinity.edu/educ_understandings Repository Citation Webber, Miguel Angel, "Looking Up! What is our place in the universe? - An Astronomy UbD for 8th Grade" (2019). Understanding by Design: Complete Collection. 445. https://digitalcommons.trinity.edu/educ_understandings/445 This Instructional Material is brought to you for free and open access by the Understanding by Design at Digital Commons @ Trinity. For more information about this unie, please contact the author(s): [email protected]. For information about the series, including permissions, please contact the administrator: [email protected]. v 8GrSci Looking Up - What is our place in the universe? Unit Title Looking Up - What is our place in the universe? Course(s) 8th Grade Science Designed by Miguel Angel Webber Martinez Time Frame 17 Class Days: W1​ August 26 - 30 (5) W2​ September 3 - 6 (4) W3​ September 9 - 13 (5) W4​ September 16 - 18 (3) Stage 1- Desired Results Establish Goals 8th Grade Science TEKS ● 8.8A​ Describe components of the universe, including stars, nebulae, and galaxies. Use models such as the Hertzsprung-Russell diagram for classification. ● 8.8B Recognize that the Sun is a medium-sized star located in a spiral arm of the Milky Way galaxy, and that the Sun is many thousands of times closer to Earth than any other star. ● 8.8C Identify how different wavelengths of the electromagnetic spectrum, such as visible light and radio waves, are used to gain information about components in the universe.
    [Show full text]
  • Monthly Newsletter of the Durban Centre - March 2018
    Page 1 Monthly Newsletter of the Durban Centre - March 2018 Page 2 Table of Contents Chairman’s Chatter …...…………………….……….………..….…… 3 Andrew Gray …………………………………………...………………. 5 The Hyades Star Cluster …...………………………….…….……….. 6 At the Eye Piece …………………………………………….….…….... 9 The Cover Image - Antennae Nebula …….……………………….. 11 Galaxy - Part 2 ….………………………………..………………….... 13 Self-Taught Astronomer …………………………………..………… 21 The Month Ahead …..…………………...….…….……………..…… 24 Minutes of the Previous Meeting …………………………….……. 25 Public Viewing Roster …………………………….……….…..……. 26 Pre-loved Telescope Equipment …………………………...……… 28 ASSA Symposium 2018 ………………………...……….…......…… 29 Member Submissions Disclaimer: The views expressed in ‘nDaba are solely those of the writer and are not necessarily the views of the Durban Centre, nor the Editor. All images and content is the work of the respective copyright owner Page 3 Chairman’s Chatter By Mike Hadlow Dear Members, The third month of the year is upon us and already the viewing conditions have been more favourable over the last few nights. Let’s hope it continues and we have clear skies and good viewing for the next five or six months. Our February meeting was well attended, with our main speaker being Dr Matt Hilton from the Astrophysics and Cosmology Research Unit at UKZN who gave us an excellent presentation on gravity waves. We really have to be thankful to Dr Hilton from ACRU UKZN for giving us his time to give us presentations and hope that we can maintain our relationship with ACRU and that we can draw other speakers from his colleagues and other research students! Thanks must also go to Debbie Abel and Piet Strauss for their monthly presentations on NASA and the sky for the following month, respectively.
    [Show full text]
  • Analytical Properties of Einasto Dark Matter Haloes
    A&A 540, A70 (2012) Astronomy DOI: 10.1051/0004-6361/201118543 & c ESO 2012 Astrophysics Analytical properties of Einasto dark matter haloes E. Retana-Montenegro1 , E. Van Hese2, G. Gentile2,M.Baes2, and F. Frutos-Alfaro1 1 Escuela de Física, Universidad de Costa Rica, 11501 San Pedro, Costa Rica e-mail: [email protected] 2 Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281-S9, 9000 Gent, Belgium e-mail: [email protected] Received 29 November 2011 / Accepted 19 January 2012 ABSTRACT Recent high-resolution N-body CDM simulations indicate that nonsingular three-parameter models such as the Einasto profile perform better than the singular two-parameter models, e.g. the Navarro, Frenk and White, in fitting a wide range of dark matter haloes. While many of the basic properties of the Einasto profile have been discussed in previous studies, a number of analytical properties are still not investigated. In particular, a general analytical formula for the surface density, an important quantity that defines the lensing properties of a dark matter halo, is still lacking to date. To this aim, we used a Mellin integral transform formalism to derive a closed expression for the Einasto surface density and related properties in terms of the Fox H and Meijer G functions, which can be written as series expansions. This enables arbitrary-precision calculations of the surface density and the lensing properties of realistic dark matter halo models. Furthermore, we compared the Sérsic and Einasto surface mass densities and found differences between them, which implies that the lensing properties for both profiles differ.
    [Show full text]
  • And Yet It Flips: Connecting Galactic Spin and the Cosmic
    MNRAS 000,1–17 (2019) Preprint 5 June 2019 Compiled using MNRAS LATEX style file v3.0 And yet it flips: connecting galactic spin and the cosmic web Katarina Kraljic,1? Romeel Davé,1;2;3 and Christophe Pichon4;5 1 Institute for Astronomy, Royal Observatory, Edinburgh EH9 3HJ, United Kingdom 2 University of the Western Cape, Bellville, Cape Town 7535, South Africa 3 South African Astronomical Observatories, Observatory, Cape Town 7925, South Africa 4 Sorbonne Universités, UPMC Univ Paris 6 et CNRS, UMR 7095, Institut d’Astrophysique de Paris, 98 bis bd Arago, 75014 Paris, France 5 Korea Institute for Advanced Study (KIAS), 85 Hoegiro, Dongdaemun-gu, Seoul, 02455, Republic of Korea Accepted XXX. Received YYY; in original form ZZZ ABSTRACT We study the spin alignment of galaxies and halos with respect to filaments and walls of the cosmic web, identified with DISPERSE, using the SIMBA simulation from z = 0 − 2. Massive halos’ spins are oriented perpendicularly to their closest filament’s axis and walls, while low mass halos tend to have their spins parallel to filaments and in the plane of walls. A simi- lar mass-dependent spin flip is found for galaxies, albeit with a weaker signal particularly at low mass and low-z, suggesting that galaxies’ spins retain memory of their larger-scale en- vironment. Low-z star-forming and rotation-dominated galaxies tend to have spins parallel to nearby filaments, while quiescent and dispersion-dominated galaxies show preferentially perpendicular orientation; the star formation trend can be fully explained by the stellar mass correlation, but the morphology trend cannot.
    [Show full text]
  • Ashes of Exploding Suns, Monuments to Dust
    Ashes of Exploding Suns, Monuments to Dust Christopher McKi tterick when skies are hanged and oceans drowned, the single secret will still be man —e.e. cummings Extinction +15,000 years Scientists say you do not dream during cryosleep. This is untrue. If you enter the state intend - ing to kill billions, the subconscious mind punishes. Cryosleep dreams move slowly, the way glaciers take thousands of years grinding a civilization to gravel. Violence acting almost imper - ceptibly over protracted time still leaves enduring scars, like aging. Warming away the residue of hibernation, the sleep capsule lit my nerves on fire. The all- consuming pain of being resurrected is difficult to convey. A facsimile of your own blood dis - places hibernation fluid. Senses scatter and conflate. Skin crackles and muscles creak as the nano-bath electrifies. To activate switched-off nerves, embeds twitch one’s body in disconcert - ing jolts. Teeth rattle. Images from dream and memory overwhelm the casket’s synesthetic re - ality. Nightmares fade and rise again. No matter how tranquil one’s normal state, panic grips the throat. 130 NOVEMBER /D ECEMBER 2018 This phase lasts longer than the corporeal shock of waking. Not forever, though the hind - brain panics. After enough practice, discipline helps dissociate from the sensations. This suf - fering will end, like all things. If you fail to revive, you die before this liminal state, blissfully unaware. Those waking from cryo often envy those who remain forever asleep. What does it mean to live? An accurate measure is awareness of pain. As I surfaced toward consciousness, the reason for retreating into hibernation all those cen - turies ago crashed through me, like meltwater rushing beneath ice.
    [Show full text]
  • The Cosmic Ballet II: Spin Alignment of Galaxies and Haloes with Large-Scale filaments in the EAGLE Simulation
    MNRAS 000,1–18 (2019) Preprint 19 March 2019 Compiled using MNRAS LATEX style file v3.0 The Cosmic Ballet II: Spin alignment of galaxies and haloes with large-scale filaments in the EAGLE simulation Punyakoti Ganeshaiah Veena,1;2? Marius Cautun,3 Elmo Tempel,2;4 Rien van de Weygaert1 and Carlos S. Frenk3 1Kapteyn Astronomical Institute, University of Groningen,PO Box 800, 9747 AD, Groningen, The Netherlands 2Tartu Observatory, University of Tartu, Observatooriumi 1, 61602 To~ravere, Estonia 3Department of Physics, Institute for Computational Cosmology, University of Durham, South Road, Durham, DH1 3LE, UK 4Leibniz-Institut fu¨r Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany 19 March 2019 ABSTRACT We investigate the alignment of galaxies and haloes relative to cosmic web filaments using the EAGLE hydrodynamical simulation. We identify filaments by applying the NEXUS+ method to the mass distribution and the Bisous formalism to the galaxy distribution. Both web finders return similar filamentary structures that are well aligned and that contain comparable galaxy populations. EAGLE haloes have an identical spin alignment with filaments as their counter- parts in dark matter only simulations: a complex mass dependent trend with low mass haloes spinning preferentially parallel to and high mass haloes spinning preferentially perpendicular to filaments. In contrast, galaxy spins do not show such a spin transition and have a propensity for perpendicular alignments at all masses, with the degree of alignment being largest for mas- sive galaxies. This result is valid for both NEXUS+ and Bisous filaments. When splitting by morphology, we find that elliptical galaxies show a stronger orthogonal spin–filament align- ment than spiral galaxies of similar mass.
    [Show full text]
  • Arxiv:1408.1133V1
    Accepted for publication in The Astrophysical Journal on 23 June 2014. A Preprint typeset using LTEX style emulateapj v. 5/2/11 THE Gˆ INFRARED SEARCH FOR EXTRATERRESTRIAL CIVILIZATIONS WITH LARGE ENERGY SUPPLIES. I. BACKGROUND AND JUSTIFICATION 1,2 1,3,4 1,2 5 J. T. Wright , B. Mullan , S. SigurD sson , and M. S. Povich Accepted for publication in The Astrophysical Journal on 23 June 2014. ABSTRACT We motivate the Gˆ infrared search for extraterrestrial civilizations with large energy supplies. We discuss some philosophical difficulties of SETI, and how communication SETI circumvents them. We review “Dysonian SETI”, the search for artifacts of alien civilizations, and find that it is highly complementary to traditional communication SETI; the two together might succeed where either one, alone, has not. We discuss the argument of Hart (1975) that spacefaring life in the Milky Way should be either galaxy-spanning or non-existent, and examine a portion of his argument that we dub the “monocultural fallacy”. We discuss some rebuttals to Hart that invoke sustainability and predict long Galaxy colonization timescales. We find that the maximum Galaxy colonization timescale is actually much shorter than previous work has found (< 109 yr), and that many “sustainability” counter- arguments to Hart’s thesis suffer from the monocultural fallacy. We extend Hart’s argument to alien energy supplies, and argue that detectably large energy supplies can plausibly be expected to exist because life has potential for exponential growth until checked by resource or other limitations, and intelligence implies the ability to overcome such limitations. As such, if Hart’s thesis is correct then searches for large alien civilizations in other galaxies may be fruitful; if it is incorrect, then searches for civilizations within the Milky Way are more likely to succeed than Hart argued.
    [Show full text]
  • Cosmology Meets Condensed Matter
    Cosmology Meets Condensed Matter Mark N. Brook Thesis submitted to the University of Nottingham for the degree of Doctor of Philosophy. July 2010 The Feynman Problem-Solving Algorithm: 1. Write down the problem 2. Think very hard 3. Write down the answer – R. P. Feynman att. to M. Gell-Mann Supervisor: Prof. Peter Coles Examiners: Prof. Ed Copeland Prof. Ray Rivers Abstract This thesis is concerned with the interface of cosmology and condensed matter. Although at either end of the scale spectrum, the two disciplines have more in common than one might think. Condensed matter theorists and high-energy field theorists study, usually independently, phenomena embedded in the structure of a quantum field theory. It would appear at first glance that these phenomena are disjoint, and this has often led to the two fields developing their own procedures and strategies, and adopting their own nomenclature. We will look at some concepts that have helped bridge the gap between the two sub- jects, enabling progress in both, before incorporating condensed matter techniques to our own cosmological model. By considering ideas from cosmological high-energy field theory, we then critically examine other models of astrophysical condensed mat- ter phenomena. In Chapter 1, we introduce the current cosmological paradigm, and present a somewhat historical overview of the interplay between cosmology and condensed matter. Many concepts are introduced here that later chapters will follow up on, and we give some examples in which condensed matter physics has had a very real effect on informing cosmology. We also reflect on the most recent incarnations of the condensed matter / cosmology interplay, and the future of these developments.
    [Show full text]