DOCSLIB.ORG

Sukhbold and Woosley, 2014; Woosley and Heger

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Sukhbold and Woosley, 2014; Woosley and Heger UC Santa Cruz UC Santa Cruz Electronic Theses and Dissertations Title The Evolution and Explosion of Massive Stars Permalink https://escholarship.org/uc/item/6gr8s8cp Author Sukhbold, Tuguldur Publication Date 2016 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA SANTA CRUZ THE EVOLUTION AND EXPLOSION OF MASSIVE STARS A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in ASTRONOMY & ASTROPHYSICS by Tuguldur Sukhbold September 2016 The Dissertation of Tuguldur Sukhbold is approved: Professor Stan Woosley, Chair Professor Greg Laughlin Professor Jonathan Fortney Dean Tyrus Miller Vice Provost and Dean of Graduate Studies Copyright c by Tuguldur Sukhbold 2016 Table of Contents List of Figuresv List of Tables vii Abstract viii Dedication ix Acknowledgmentsx 1 Introduction1 1.1 Overview.....................................1 1.2 Brief Basic Background..............................3 1.3 KEPLER code................................... 14 1.4 Structure of this thesis.............................. 15 1.5 Related works not contained in this thesis.................... 17 2 The Compactness of Presupernova Stellar Cores 20 2.1 Introduction.................................... 20 2.2 Surveys of presupernova evolution........................ 24 2.2.1 Solar Metallicity Stars.......................... 25 2.2.2 Low Metallicity Stars........................... 26 2.2.3 Choice of Fiducial Mass and Time for Evaluating the Compactness.. 29 2.3 Physical Basis of the Behaviour of the Compactness Parameter......... 31 2.3.1 Evolution Through Central Carbon Depletion.............. 32 2.3.2 Carbon Shell Burning.......................... 33 2.3.3 From Oxygen Depletion to Silicon Depletion.............. 37 2.3.4 From Silicon Depletion to Presupernova................. 38 2.3.5 Fine Scale Variations and Convergence................. 39 2.3.6 Stars Over 30 M ............................ 41 2.4 Sensitivity to Code Physics............................ 43 2.4.1 Sensitivity to Semiconvection and Overshoot Mixing.......... 43 iii 2.4.2 Survey of Solar Metallicity Stars Using MESA .............. 50 2.4.3 Sensitivity to Uncertain Nuclear Physics - 12C(α;γ)16O......... 55 2.5 Surveys with Bare Carbon-Oxygen Cores.................... 57 2.6 Conclusions.................................... 59 3 Core-Collapse Supernovae from 9 to 120 M based on Neutrino-Powered Explo- sions 99 3.1 Introduction.................................... 99 3.2 Presupernova Models............................... 103 3.2.1 Stellar Physics.............................. 103 3.2.2 Explosion Calibration Models...................... 105 3.2.3 Presupernova Models used for this Study................ 111 3.3 Explosion Modelling............................... 115 3.3.1 Explosion Simulations with PHOTB ................... 116 3.3.2 Simulating Explosions with KEPLER .................. 126 3.4 Explosion Properties............................... 129 3.4.1 Relation to Core Compactness...................... 131 3.4.2 Systematics of Explosion Energy and 56Ni Mass............ 132 3.5 Bound Remnants................................. 136 3.5.1 Neutron Stars............................... 136 3.5.2 Black Holes................................ 139 3.6 Nucleosynthesis.................................. 142 3.6.1 9-12 M ................................. 145 3.6.2 12-30 M ................................. 147 3.6.3 30-120 M ................................ 148 3.6.4 Integrated Yields............................. 149 3.6.5 Type Ia Supernova Contribution..................... 158 3.7 Light Curves................................... 160 3.7.1 Type IIP.................................. 161 3.7.2 Type Ib/c................................. 171 3.7.3 Type IIL................................. 173 3.8 Conclusions.................................... 175 4 The Most Luminous Supernovae 224 4.1 Introduction.................................... 224 4.2 Prompt Explosions and Pair-Instability...................... 225 4.3 Radioactivity................................... 227 4.4 Colliding Shells.................................. 229 4.4.1 Generic Models.............................. 229 4.4.2 Pulsational-pair instability supernovae.................. 231 4.5 Magnetars..................................... 232 4.6 Summary and Conclusions............................ 236 iv List of Figures 2.1 ξ2:5from old survey models............................ 71 2.2 ξ2:5as a function of initial mass for solar metallicity models........... 72 2.3 S, U and SH series models in comparison.................... 73 2.4 He and CO core masses for S, U and SH series................. 74 2.5 Central C mass fractions at the time of C.ign................... 75 2.6 Presupernova radii of S, U and SH series..................... 76 2.7 Presupernova ξ defined at different times and locations............. 77 2.8 Convective history of a 15 M Z model..................... 78 2.9 ξ2:5evolution until C.dep............................. 79 2.10 Evolution of degeneracy of the core....................... 80 2.11 Timing and location of convective shells..................... 81 2.12 ξ2:5 evolution from C.dep to O.dep........................ 82 2.13 Different convective histories of Carbon and Oxygen burning.......... 83 2.14 ξ2:5 from O.dep to Si.dep............................. 84 2.15 ξ2:5 evolution from Si.dep to preSN....................... 85 2.16 Convective history after core Si.dep....................... 86 2.17 Time from Si.dep to preSN............................ 87 2.18 ξ2:5 dependence on zoning and timestep..................... 88 2.19 Convective episodes of SH series......................... 89 2.20 Dependence of ξ2:5 of semiconvection...................... 90 2.21 Dependence of ξ2:5 on overshooting....................... 91 2.22 MCO is a better discriminant that MZAMS ..................... 92 2.23 MESA models in comparison with KEPLER models............... 93 2.24 Evolution of ξ2:5 in Mov series.......................... 94 12 16 2.25 ξ2:5 dependence on variable C(α;γ) O rate.................. 95 2.26 Bare CO cores from KEPLER and MESA at O.dep................ 96 2.27 Bare CO cores in comparison with full stars at preSN.............. 97 2.28 Correlation between preSN ξ2:5 and BE outside the iron-core.......... 98 3.1 Compactness parameter for each progenitor................... 189 3.2 HR diagram for SN 1987A models........................ 190 v 3.3 Core structures for the lightest progenitor models................ 191 3.4 Agreement between two series at low progenitor initial mass.......... 192 3.5 Mass enclosing internal 3000 km for each progenitor.............. 193 3.6 Baryonic shell diagram for two sample explosions................ 194 3.7 Transforming PHOTB trajectories into KEPLER ................. 195 3.8 Total iron production from KEPLER and PHOTB ................ 196 3.9 Explosion outcomes from five main engines................... 197 3.10 Percentage of type II supernovae......................... 198 3.11 Mass derivative of binding energy as a criterion of explosion.......... 199 3.12 Correlation of 56 mass and explosion energy with compactness......... 200 3.13 Correlation between nickel mass and explosion enegry............. 201 3.14 Distribution of neutron star masses........................ 202 3.15 The mass “budget” for each progenitor as exploded by engine W18....... 203 3.16 Distribution of black hole masses......................... 204 3.17 Production from lightest stars........................... 205 3.18 Production from stars between 12 and 30 M .................. 206 3.19 Production from heaviest stars.......................... 207 3.20 Elemental integrated yields............................ 208 3.21 Integrated isotope yields from engine W18.................... 209 3.22 Integrated isotope yields from engine N20.................... 210 3.23 The effect of steeper IMF on nucleosynthesis.................. 211 3.24 Ia contribution from sub-Chandrasekhar mass model.............. 212 3.25 Ia contribution from Chandrasekhar mass model................. 213 3.26 All light curves.................................. 214 3.27 Scaling law for the plateau luminosity...................... 215 3.28 Plateau durations and correction for radioactivity................ 216 3.29 The extension of plateau duration through 56Ni decay.............. 217 3.30 Scaling law for plateau durations......................... 218 3.31 Envelope and initial progenitor mass....................... 219 3.32 Correlation between plateau luminosity and duration.............. 220 3.33 Explosion energy from plateau.......................... 221 3.34 Progenitor mass from plateau........................... 222 3.35 56Ni mass estimates from Ib/c light curve.................... 223 4.1 Light curves from two different prompt energy depositions........... 240 4.2 Magnetar powered model for ASASSN-15lh................... 241 vi List of Tables 1.1 Evolution of 15 M model............................ 19 2.1 Calculations.................................... 65 2.1 Calculations.................................... 66 2.2 He Core and CO Core Sizes........................... 67 2.2 He Core and CO Core Sizes........................... 68 2.2 He Core and CO Core Sizes........................... 69 2.3 X(12C) and 12C(α;γ)16O ............................. 70 2.4 Critical Masses for Central Carbon Burning................... 70 3.1 SN 1987A Models................................ 185
Load more

Recommended publications
  • Plasma Physics and Pulsars
    Plasma Physics and Pulsars On the evolution of compact o bjects and plasma physics in weak and strong gravitational and electromagnetic fields by Anouk Ehreiser supervised by Axel Jessner, Maria Massi and Li Kejia as part of an internship at the Max Planck Institute for Radioastronomy, Bonn March 2010 2 This composition was written as part of two internships at the Max Planck Institute for Radioastronomy in April 2009 at the Radiotelescope in Effelsberg and in February/March 2010 at the Institute in Bonn. I am very grateful for the support, expertise and patience of Axel Jessner, Maria Massi and Li Kejia, who supervised my internship and introduced me to the basic concepts and the current research in the field. Contents I. Life-cycle of stars 1. Formation and inner structure 2. Gravitational collapse and supernova 3. Star remnants II. Properties of Compact Objects 1. White Dwarfs 2. Neutron Stars 3. Black Holes 4. Hypothetical Quark Stars 5. Relativistic Effects III. Plasma Physics 1. Essentials 2. Single Particle Motion in a magnetic field 3. Interaction of plasma flows with magnetic fields – the aurora as an example IV. Pulsars 1. The Discovery of Pulsars 2. Basic Features of Pulsar Signals 3. Theoretical models for the Pulsar Magnetosphere and Emission Mechanism 4. Towards a Dynamical Model of Pulsar Electrodynamics References 3 Plasma Physics and Pulsars I. The life-cycle of stars 1. Formation and inner structure Stars are formed in molecular clouds in the interstellar medium, which consist mostly of molecular hydrogen (primordial elements made a few minutes after the beginning of the universe) and dust.
    [Show full text]
  • Surface Structure of Quark Stars with Magnetic Fields
    PRAMANA °c Indian Academy of Sciences Vol. 67, No. 5 | journal of November 2006 physics pp. 937{949 Surface structure of quark stars with magnetic ¯elds PRASHANTH JAIKUMAR Department of Physics and Astronomy, Ohio University, Athens, OH 45701, USA E-mail: [email protected] Abstract. We investigate the impact of magnetic ¯elds on the electron distribution of the electrosphere of quark stars. For moderately strong magnetic ¯elds of B » 1013 G, quantization e®ects are generally weak due to the large number density of electrons at surface, but can nevertheless a®ect the photon emission properties of quark stars. We outline the main observational characteristics of quark stars as determined by their surface emission, and briefly discuss their formation in explosive events termed as quark-novae, which may be connected to the r-process. Keywords. Quark stars; magnetic ¯elds; nucleosynthesis. PACS Nos 26.60.+c; 24.85.+p; 97.60.Jd 1. Introduction There is a renewed interest in the theory and observation of strange quark stars, which are believed to contain, or be entirely composed of, decon¯ned quark mat- ter [1]. An observational con¯rmation of their existence would be conclusive ev- idence of quark decon¯nement at large baryon densities, an expected feature of quantum chromodynamics (QCD). Furthermore, discovery of a stable bare quark star a±rms the Bodmer{Terazawa{Witten conjecture [2], that at high enough den- sity, strange quark matter, composed of up, down and strange quarks, is absolutely stable with respect to nuclear matter. This intriguing hypothesis is over three decades old, and bare quark stars are but one possible realization put forward in the intervening years.
    [Show full text]
  • Correction: Corrigendum: the Superluminous Transient ASASSN
    LETTERS PUBLISHED: 12 DECEMBER 2016 | VOLUME: 1 | ARTICLE NUMBER: 0002 The superluminous transient ASASSN-15lh as a tidal disruption event from a Kerr black hole G. Leloudas1,​2*, M. Fraser3, N. C. Stone4, S. van Velzen5, P. G. Jonker6,​7, I. Arcavi8,​9, C. Fremling10, J. R. Maund11, S. J. Smartt12, T. Krühler13, J. C. A. Miller-Jones14, P. M. Vreeswijk1, A. Gal-Yam1, P. A. Mazzali15,​16, A. De Cia17, D. A. Howell8,​18, C. Inserra12, F. Patat17, A. de Ugarte Postigo2,​19, O. Yaron1, C. Ashall15, I. Bar1, H. Campbell3,​20, T.-W. Chen13, M. Childress21, N. Elias-Rosa22, J. Harmanen23, G. Hosseinzadeh8,​18, J. Johansson1, T. Kangas23, E. Kankare12, S. Kim24, H. Kuncarayakti25,​26, J. Lyman27, M. R. Magee12, K. Maguire12, D. Malesani2, S. Mattila3,​23,​28, C. V. McCully8,​18, M. Nicholl29, S. Prentice15, C. Romero-Cañizales24,​25, S. Schulze24,​25, K. W. Smith12, J. Sollerman10, M. Sullivan21, B. E. Tucker30,​31, S. Valenti32, J. C. Wheeler33 and D. R. Young12 8 12,13 When a star passes within the tidal radius of a supermassive has a mass >10 M⊙ , a star with the same mass as the Sun black hole, it will be torn apart1. For a star with the mass of the could be disrupted outside the event horizon if the black hole 8 14 Sun (M⊙) and a non-spinning black hole with a mass <10 M⊙, were spinning rapidly . The rapid spin and high black hole the tidal radius lies outside the black hole event horizon2 and mass can explain the high luminosity of this event.
    [Show full text]
  • Collapsing Supra-Massive Magnetars: Frbs, the Repeating FRB121102 and Grbs
    J. Astrophys. Astr. (2018) 39:14 © Indian Academy of Sciences https://doi.org/10.1007/s12036-017-9499-9 Review Collapsing supra-massive magnetars: FRBs, the repeating FRB121102 and GRBs PATRICK DAS GUPTA∗ and NIDHI SAINI Department of Physics and Astrophysics, University of Delhi, Delhi 110007, India. ∗Corresponding author. E-mail: [email protected], [email protected] MS received 30 August 2017; accepted 3 October 2017; published online 10 February 2018 Abstract. Fast Radio Bursts (FRBs) last for ∼ few milli-seconds and, hence, are likely to arise from the gravitational collapse of supra-massive, spinning neutron stars after they lose the centrifugal support (Falcke & Rezzolla 2014). In this paper, we provide arguments to show that the repeating burst, FRB 121102, can also be modeled in the collapse framework provided the supra-massive object implodes either into a Kerr black hole surrounded by highly magnetized plasma or into a strange quark star. Since the estimated rates of FRBs and SN Ib/c are comparable, we put forward a common progenitor scenario for FRBs and long GRBs in which only those compact remnants entail prompt γ -emission whose kick velocities are almost aligned or anti-aligned with the stellar spin axes. In such a scenario, emission of detectable gravitational radiation and, possibly, of neutrinos are expected to occur during the SN Ib/c explosion as well as, later, at the time of magnetar implosion. Keywords. FRBs—FRB 121102—Kerr black holes—Blandford–Znajek process—strange stars—GRBs— pre-natal kicks. 1. Introduction 43% linear polarization and 3% circular polarization (Petroff et al.
    [Show full text]
  • Report from the Dark Energy Task Force (DETF)
    Fermi National Accelerator Laboratory Fermilab Particle Astrophysics Center P.O.Box 500 - MS209 Batavia, Il l i noi s • 60510 June 6, 2006 Dr. Garth Illingworth Chair, Astronomy and Astrophysics Advisory Committee Dr. Mel Shochet Chair, High Energy Physics Advisory Panel Dear Garth, Dear Mel, I am pleased to transmit to you the report of the Dark Energy Task Force. The report is a comprehensive study of the dark energy issue, perhaps the most compelling of all outstanding problems in physical science. In the Report, we outline the crucial need for a vigorous program to explore dark energy as fully as possible since it challenges our understanding of fundamental physical laws and the nature of the cosmos. We recommend that program elements include 1. Prompt critical evaluation of the benefits, costs, and risks of proposed long-term projects. 2. Commitment to a program combining observational techniques from one or more of these projects that will lead to a dramatic improvement in our understanding of dark energy. (A quantitative measure for that improvement is presented in the report.) 3. Immediately expanded support for long-term projects judged to be the most promising components of the long-term program. 4. Expanded support for ancillary measurements required for the long-term program and for projects that will improve our understanding and reduction of the dominant systematic measurement errors. 5. An immediate start for nearer term projects designed to advance our knowledge of dark energy and to develop the observational and analytical techniques that will be needed for the long-term program. Sincerely yours, on behalf of the Dark Energy Task Force, Edward Kolb Director, Particle Astrophysics Center Fermi National Accelerator Laboratory Professor of Astronomy and Astrophysics The University of Chicago REPORT OF THE DARK ENERGY TASK FORCE Dark energy appears to be the dominant component of the physical Universe, yet there is no persuasive theoretical explanation for its existence or magnitude.
    [Show full text]
  • Perrett RTA.Pdf
    The Astronomical Journal, 140:518–532, 2010 August doi:10.1088/0004-6256/140/2/518 C 2010. The American Astronomical Society. All rights reserved. Printed in the U.S.A. REAL-TIME ANALYSIS AND SELECTION BIASES IN THE SUPERNOVA LEGACY SURVEY∗ K. Perrett1,2, D. Balam3, M. Sullivan4, C. Pritchet5, A. Conley1,6, R. Carlberg1,P.Astier7, C. Balland7,S.Basa8, D. Fouchez9,J.Guy7, D. Hardin7,I.M.Hook3,10, D. A. Howell11,12,R.Pain7, and N. Regnault7 1 Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON, M5S 3H4, Canada; [email protected] 2 Network Information Operations, DRDC Ottawa, 3701 Carling Avenue, Ottawa, ON K1A 0Z4, Canada 3 Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada 4 Department of Physics (Astrophysics), University of Oxford, DWB, Keble Road, Oxford OX1 3RH, UK; [email protected] 5 Department of Physics & Astronomy, University of Victoria, P.O. Box 3055, Stn CSC, Victoria, BC V8W 3P6, Canada 6 Center for Astrophysics and Space Astronomy, University of Colorado, 593 UCB, Boulder, CO 80309-0593, USA 7 LPNHE, CNRS-IN2P3 and University of Paris VI & VII, 75005 Paris, France 8 Laboratoire d’Astrophysique de Marseille, Poledel’ˆ Etoile´ Site de Chateau-Gombert,ˆ 38, rue Fred´ eric´ Joliot-Curie, 13388 Marseille cedex 13, France 9 CPPM, CNRS-IN2P3 and University Aix Marseille II, Case 907, 13288 Marseille cedex 9, France 10 INAF, Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monteporzio (RM), Italy 11 Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117, USA 12 Department of Physics, University of California, Santa Barbara, Broida Hall, Mail Code 9530, Santa Barbara, CA 93106-9530, USA Received 2010 February 17; accepted 2010 June 4; published 2010 July 1 ABSTRACT The Supernova Legacy Survey (SNLS) has produced a high-quality, homogeneous sample of Type Ia supernovae (SNe Ia) out to redshifts greater than z = 1.
    [Show full text]
  • When Neutron Stars Melt, What’S Left Behind Is Spectacular Explosion
    Space oddity implodes. The outer layers are cast off in a When neutron stars melt, what’s left behind is spectacular explosion. What’s left behind is truly strange. Anil Ananthaswamy reports a rapidly spinning neutron star, which as the name implies is made mainly of neutrons, with a crust of iron. Whirling up to 1000 times per second, a neutron star is constantly shedding magnetic fields. Over time, this loss of energy causes the star to spin slower and slower. As it spins down, the centrifugal forces that kept gravity at bay start weakening, allowing gravity to squish the star still further. In what is a blink of an eye in cosmic time, the neutrons can be converted to strange N 22 September last year, the website of fundamental building blocks of matter in quark matter, which is a soup of up, down and The Astronomer’s Telegram alerted ways that even machines like the Large strange quarks. In theory, this unusual change Oresearchers to a supernova explosion in Hadron Collider cannot. happens when the density inside the neutron a spiral galaxy about 84 million light years Astrophysicists can thank string theorist star starts increasing. New particles called away. There was just one problem. The same Edward Witten for quark stars. In 1984, he hyperons begin forming that contain at least object, SN 2009ip, had blown up in a similarly hypothesised that protons and neutrons one strange quark bound to others. spectacular fashion just weeks earlier. Such may not be the most stable forms of matter. However, the appearance of hyperons stars shouldn’t go supernova twice, let alone Both are made of two types of smaller marks the beginning of the end of the neutron in quick succession.
    [Show full text]
  • Publications RENOIR – 24 Sep 2021 Article
    Publications RENOIR { 24 Sep 2021 article 2021 1. The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: one thousand multi-tracer mock catalogues with redshift evolution and systematics for galaxies and quasars of the final data release, C. Zhao et al., Mon. Not. Roy. Astron. Soc 503 (2021) 1149-1173 2. Euclid preparation: XI. Mean redshift determination from galaxy redshift probabilities for cosmic shear tomography, O. Ilbert et al., Euclid Collaboration, Astron. Astrophys. 647 (2021) A117 2020 1. Improving baryon acoustic oscillation measurement with the combination of cosmic voids and galaxies, C. Zhao et al., SDSS Collaboration, Mon. Not. Roy. Astron. Soc 491 (2020) 4554-4572 2. Strong Dependence of Type Ia Supernova Standardization on the Local Specific Star Formation Rate, M. Rigault et al., Nearby Supernova Factory Collaboration, Astron. Astrophys. 644 (2020) A176 3. High-precision Monte-Carlo modelling of galaxy distribution, P. Baratta et al., Astron. Astrophys. 633 (2020) A26 4. Constraints on the growth of structure around cosmic voids in eBOSS DR14, A. J. Hawken et al., J. Cosmol. Astropart. P 2006 (2020) 012 5. SUGAR: An improved empirical model of Type Ia Supernovae based on spectral features, P.-F. L´eget et al., Nearby Supernova Factory Collaboration, Astron. Astrophys. 636 (2020) A46 6. Euclid: Reconstruction of Weak Lensing mass maps for non- Gaussianity studies, S. Pires et al., Euclid Collaboration, Astron. Astrophys. 638 (2020) A141 7. Euclid preparation: VII. Forecast validation for Euclid cosmological probes, A. Blanchard et al., Euclid Collaboration, Astron. Astrophys. 642 (2020) A191 8. Euclid preparation: VI. Verifying the Performance of Cosmic Shear Experiments, P.
    [Show full text]
  • Axps & Sgrs: Magnetar Or Quarctar?
    [Show full text]
  • Euclid: Superluminous Supernovae in the Deep Survey? C
    A&A 609, A83 (2018) Astronomy DOI: 10.1051/0004-6361/201731758 & c ESO 2018 Astrophysics Euclid: Superluminous supernovae in the Deep Survey? C. Inserra1; 2, R. C. Nichol3, D. Scovacricchi3, J. Amiaux4, M. Brescia5, C. Burigana6; 7; 8, E. Cappellaro9, C. S. Carvalho30, S. Cavuoti5; 11; 12, V. Conforti13, J.-C. Cuillandre4; 14; 15, A. da Silva10; 16, A. De Rosa13, M. Della Valle5; 17, J. Dinis10; 16, E. Franceschi13, I. Hook18, P. Hudelot19, K. Jahnke20, T. Kitching21, H. Kurki-Suonio22, I. Lloro23, G. Longo11; 12, E. Maiorano13, M. Maris24, J. D. Rhodes25, R. Scaramella26, S. J. Smartt2, M. Sullivan1, C. Tao27; 28, R. Toledo-Moreo29, I. Tereno16; 30, M. Trifoglio13, and L. Valenziano13 (Affiliations can be found after the references) Received 11 August 2017 / Accepted 3 October 2017 ABSTRACT Context. In the last decade, astronomers have found a new type of supernova called superluminous supernovae (SLSNe) due to their high peak luminosity and long light-curves. These hydrogen-free explosions (SLSNe-I) can be seen to z ∼ 4 and therefore, offer the possibility of probing the distant Universe. Aims. We aim to investigate the possibility of detecting SLSNe-I using ESA’s Euclid satellite, scheduled for launch in 2020. In particular, we study the Euclid Deep Survey (EDS) which will provide a unique combination of area, depth and cadence over the mission. Methods. We estimated the redshift distribution of Euclid SLSNe-I using the latest information on their rates and spectral energy distribution, as well as known Euclid instrument and survey parameters, including the cadence and depth of the EDS.
    [Show full text]
  • Probing the Nuclear Equation of State from the Existence of a 2.6 M Neutron Star: the GW190814 Puzzle
    S S symmetry Article Probing the Nuclear Equation of State from the Existence of a ∼2.6 M Neutron Star: The GW190814 Puzzle Alkiviadis Kanakis-Pegios †,‡ , Polychronis S. Koliogiannis ∗,†,‡ and Charalampos C. Moustakidis †,‡ Department of Theoretical Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; [email protected] (A.K.P.); [email protected] (C.C.M.) * Correspondence: [email protected] † Current address: Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece. ‡ These authors contributed equally to this work. Abstract: On 14 August 2019, the LIGO/Virgo collaboration observed a compact object with mass +0.08 2.59 0.09 M , as a component of a system where the main companion was a black hole with mass ∼ − 23 M . A scientific debate initiated concerning the identification of the low mass component, as ∼ it falls into the neutron star–black hole mass gap. The understanding of the nature of GW190814 event will offer rich information concerning open issues, the speed of sound and the possible phase transition into other degrees of freedom. In the present work, we made an effort to probe the nuclear equation of state along with the GW190814 event. Firstly, we examine possible constraints on the nuclear equation of state inferred from the consideration that the low mass companion is a slow or rapidly rotating neutron star. In this case, the role of the upper bounds on the speed of sound is revealed, in connection with the dense nuclear matter properties. Secondly, we systematically study the tidal deformability of a possible high mass candidate existing as an individual star or as a component one in a binary neutron star system.
    [Show full text]
  • Variable Star Classification and Light Curves Manual
    Variable Star Classification and Light Curves An AAVSO course for the Carolyn Hurless Online Institute for Continuing Education in Astronomy (CHOICE) This is copyrighted material meant only for official enrollees in this online course. Do not share this document with others. Please do not quote from it without prior permission from the AAVSO. Table of Contents Course Description and Requirements for Completion Chapter One- 1. Introduction . What are variable stars? . The first known variable stars 2. Variable Star Names . Constellation names . Greek letters (Bayer letters) . GCVS naming scheme . Other naming conventions . Naming variable star types 3. The Main Types of variability Extrinsic . Eclipsing . Rotating . Microlensing Intrinsic . Pulsating . Eruptive . Cataclysmic . X-Ray 4. The Variability Tree Chapter Two- 1. Rotating Variables . The Sun . BY Dra stars . RS CVn stars . Rotating ellipsoidal variables 2. Eclipsing Variables . EA . EB . EW . EP . Roche Lobes 1 Chapter Three- 1. Pulsating Variables . Classical Cepheids . Type II Cepheids . RV Tau stars . Delta Sct stars . RR Lyr stars . Miras . Semi-regular stars 2. Eruptive Variables . Young Stellar Objects . T Tau stars . FUOrs . EXOrs . UXOrs . UV Cet stars . Gamma Cas stars . S Dor stars . R CrB stars Chapter Four- 1. Cataclysmic Variables . Dwarf Novae . Novae . Recurrent Novae . Magnetic CVs . Symbiotic Variables . Supernovae 2. Other Variables . Gamma-Ray Bursters . Active Galactic Nuclei 2 Course Description and Requirements for Completion This course is an overview of the types of variable stars most commonly observed by AAVSO observers. We discuss the physical processes behind what makes each type variable and how this is demonstrated in their light curves. Variable star names and nomenclature are placed in a historical context to aid in understanding today’s classification scheme.
    [Show full text]