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FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
JOHN R. THORSTENSEN Address
CURRICULUM VITAE: JOHN R. THORSTENSEN Address: Department of Physics and Astronomy Dartmouth College 6127 Wilder Laboratory Hanover, NH 03755-3528; (603)-646-2869 [email protected] Undergraduate Studies: Haverford College, B. A. 1974 Astronomy and Physics double major, High Honors in both. Graduate Studies: Ph. D., 1980, University of California, Berkeley Astronomy Department Dissertation : \Optical Studies of Faint Blue X-ray Stars" Graduate Advisor: Professor C. Stuart Bowyer Employment History: Department of Physics and Astronomy, Dartmouth College: { Professor, July 1991 { present { Associate Professor, July 1986 { July 1991 { Assistant Professor, September 1980 { June 1986 Research Assistant, Space Sciences Lab., U.C. Berkeley, 1975 { 1980. Summer Student, National Radio Astronomy Observatory, 1974. Summer Student, Bartol Research Foundation, 1973. Consultant, IBM Corporation, 1973. (STARMAP program). Honors and Awards: Phi Beta Kappa, 1974. National Science Foundation Graduate Fellow, 1974 { 1977. Dorothea Klumpke Roberts Award of the Berkeley Astronomy Dept., 1978. Professional Societies: American Astronomical Society Astronomical Society of the Pacific International Astronomical Union Lifetime Publication List * \Can Collapsed Stars Close the Universe?" Thorstensen, J. R., and Partridge, R. B. 1975, Ap. J., 200, 527. \Optical Identification of Nova Scuti 1975." Raff, M. I., and Thorstensen, J. 1975, P. A. S. P., 87, 593. \Photometry of Slow X-ray Pulsars II: The 13.9 Minute Period of X Persei." Margon, B., Thorstensen, J., Bowyer, S., Mason, K. O., White, N. E., Sanford, P. W., Parkes, G., Stone, R. P. S., and Bailey, J. 1977, Ap. J., 218, 504. \A Spectrophotometric Survey of the A 0535+26 Field." Margon, B., Thorstensen, J., Nelson, J., Chanan, G., and Bowyer, S. -
Astronomy Binder
Astronomy Binder Bloomington High School South 2011 Contents 1 Astronomical Distances 2 1.1 Geometric Methods . 2 1.2 Spectroscopic Methods . 4 1.3 Standard Candle Methods . 4 1.4 Cosmological Redshift . 5 1.5 Distances to Galaxies . 5 2 Age and Size 6 2.1 Measuring Age . 6 2.2 Measuring Size . 7 3 Variable Stars 7 3.1 Pulsating Variable Stars . 7 3.1.1 Cepheid Variables . 7 3.1.2 RR Lyrae Variables . 8 3.1.3 RV Tauri Variables . 8 3.1.4 Long Period/Semiregular Variables . 8 3.2 Binary Variables . 8 3.3 Cataclysmic Variables . 11 3.3.1 Classical Nova . 11 3.3.2 Recurrent Novae . 11 3.3.3 Dwarf Novae (U Geminorum) . 11 3.3.4 X-Ray Binary . 11 3.3.5 Polar (AM Herculis) star . 12 3.3.6 Intermediate Polar (DQ Herculis) star . 12 3.3.7 Super Soft Source (SSS) . 12 3.3.8 VY Sculptoris stars . 12 3.3.9 AM Canum Venaticorum stars . 12 3.3.10 SW Sextantis stars . 13 3.3.11 Symbiotic Stars . 13 3.3.12 Pulsating White Dwarfs . 13 4 Galaxy Classification 14 4.1 Elliptical Galaxies . 14 4.2 Spirals . 15 4.3 Classification . 16 4.4 The Milky Way Galaxy (MWG . 19 4.4.1 Scale Height . 19 4.4.2 Magellanic Clouds . 20 5 Galaxy Interactions 20 6 Interstellar Medium 21 7 Active Galactic Nuclei 22 7.1 AGN Equations . 23 1 8 Spectra 25 8.1 21 cm line . 26 9 Black Holes 26 9.1 Stellar Black Holes . -
Metadata of the Chapter That Will Be Visualized Online
Metadata of the chapter that will be visualized online Chapter Title Binary Systems and Their Nuclear Explosions Copyright Year 2018 Copyright Holder The Author(s) Author Family Name Isern Particle Given Name Jordi Suffix Organization Institute of Space Sciences (ICE, CSIC) Address Barcelona, Spain Organization Institut d’Estudis Espacials de Catalunya (IEEC) Address Barcelona, Spain Email [email protected] Corresponding Author Family Name Hernanz Particle Given Name Margarita Suffix Organization Institute of Space Sciences (ICE, CSIC) Address Barcelona, Spain Organization Institut d’Estudis Espacials de Catalunya (IEEC) Address Barcelona, Spain Email [email protected] Author Family Name José Particle Given Name Jordi Suffix Organization Universitat Politècnica de Catalunya (UPC) Address Barcelona, Spain Organization Institut d’Estudis Espacials de Catalunya (IEEC) Address Barcelona, Spain Email [email protected] Abstract The nuclear energy supply of a typical star like the Sun would be ∼ 1052 erg if all the hydrogen could be incinerated into iron peak elements. Chapter 5 1 Binary Systems and Their Nuclear 2 Explosions 3 Jordi Isern, Margarita Hernanz, and Jordi José 4 5.1 Accretion onto Compact Objects and Thermonuclear 5 Runaways 6 The nuclear energy supply of a typical star like the Sun would be ∼1052 erg if all 7 the hydrogen could be incinerated into iron peak elements. Since the gravitational 8 binding energy is ∼1049 erg, it is evident that the nuclear energy content is more 9 than enough to blow up the Sun. However, stars are stable thanks to the fact that their 10 matter obeys the equation of state of a classical ideal gas that acts as a thermostat: if 11 some energy is released as a consequence of a thermal fluctuation, the gas expands, 12 the temperature drops and the instability is quenched. -
Cyclotron Radiation from Magnetic Cataclysmic Variables (Polarization, Plasmas, Magnetized, Stars, Herculis, Puppis)
Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1985 Cyclotron Radiation From Magnetic Cataclysmic Variables (Polarization, Plasmas, Magnetized, Stars, Herculis, Puppis). Paul Everett aB rrett Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Barrett, Paul Everett, "Cyclotron Radiation From Magnetic Cataclysmic Variables (Polarization, Plasmas, Magnetized, Stars, Herculis, Puppis)." (1985). LSU Historical Dissertations and Theses. 4040. https://digitalcommons.lsu.edu/gradschool_disstheses/4040 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1.The sign or “target” for pages apparently lacking from the document photographed is “ Missing Page(s)” . If it was possible to obtain the missing page(s) or section, they are spliced into the film along with adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. 2. When an image on the film is obliterated with a round black mark, it is an indication of either blurred copy because of movement during exposure, duplicate copy, or copyrighted materials that should not have been filmed. -
Permanent Superhumps in V1974 Cyg 3
Mon. Not. R. Astron. Soc. 000, 1–?? (1997) Printed 15 September 2018 (MN LaTEX style file v1.4) Permanent Superhumps in Nova V1974 Cygni 1992 A. Retter,1 E.M. Leibowitz and E.O. Ofek School of Physics and Astronomy and the Wise Observatory, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv, 69978, Israel 1 email: [email protected] accepted 1996 November 4 ABSTRACT We present results of 32 nights of CCD photometry of V1974 Cygni, from the years 1994 and 1995. We verify the presence of two distinct periodicities in the light curve: 0.0812585 day ≈ 1.95 hours and 0.0849767 d ≈ 2.04 hr. We establish that the shorter periodicity is the orbital period of the underlying binary system. The longer period oscillates with an average value of |P˙ |∼ 3 × 10−7—typical to permanent superhumps. The two periods obey the linear relation between the orbital and superhump periods that holds among members of the SU Ursae Majoris class of dwarf novae. A third periodicity of 0.083204 d ≈ 2.00 hr appeared in 1994 but not in 1995. It may be related to the recently discovered anti-superhump phenomenon. These results suggest a linkage between the classical nova V1974 Cyg and the SU UMa stars, and indicate the existence of an accretion disk and permanent superhumps in the system no later than 30 months after the nova outburst. From the precessing disk model of the superhump phenomenon we estimate that the mass ratio in the binary system is between 2.2 and 3.6. -
Meeting Program
A A S MEETING PROGRAM 211TH MEETING OF THE AMERICAN ASTRONOMICAL SOCIETY WITH THE HIGH ENERGY ASTROPHYSICS DIVISION (HEAD) AND THE HISTORICAL ASTRONOMY DIVISION (HAD) 7-11 JANUARY 2008 AUSTIN, TX All scientific session will be held at the: Austin Convention Center COUNCIL .......................... 2 500 East Cesar Chavez St. Austin, TX 78701 EXHIBITS ........................... 4 FURTHER IN GRATITUDE INFORMATION ............... 6 AAS Paper Sorters SCHEDULE ....................... 7 Rachel Akeson, David Bartlett, Elizabeth Barton, SUNDAY ........................17 Joan Centrella, Jun Cui, Susana Deustua, Tapasi Ghosh, Jennifer Grier, Joe Hahn, Hugh Harris, MONDAY .......................21 Chryssa Kouveliotou, John Martin, Kevin Marvel, Kristen Menou, Brian Patten, Robert Quimby, Chris Springob, Joe Tenn, Dirk Terrell, Dave TUESDAY .......................25 Thompson, Liese van Zee, and Amy Winebarger WEDNESDAY ................77 We would like to thank the THURSDAY ................. 143 following sponsors: FRIDAY ......................... 203 Elsevier Northrop Grumman SATURDAY .................. 241 Lockheed Martin The TABASGO Foundation AUTHOR INDEX ........ 242 AAS COUNCIL J. Craig Wheeler Univ. of Texas President (6/2006-6/2008) John P. Huchra Harvard-Smithsonian, President-Elect CfA (6/2007-6/2008) Paul Vanden Bout NRAO Vice-President (6/2005-6/2008) Robert W. O’Connell Univ. of Virginia Vice-President (6/2006-6/2009) Lee W. Hartman Univ. of Michigan Vice-President (6/2007-6/2010) John Graham CIW Secretary (6/2004-6/2010) OFFICERS Hervey (Peter) STScI Treasurer Stockman (6/2005-6/2008) Timothy F. Slater Univ. of Arizona Education Officer (6/2006-6/2009) Mike A’Hearn Univ. of Maryland Pub. Board Chair (6/2005-6/2008) Kevin Marvel AAS Executive Officer (6/2006-Present) Gary J. Ferland Univ. of Kentucky (6/2007-6/2008) Suzanne Hawley Univ. -
CCD Photometry of Nova V1500 Cygni Twenty Years After I
ACTA ASTRONOMICA Vol. 45 (1995) pp. 747±752 CCD Photometry of Nova V1500 Cygni Twenty Years After by I. S e m e n i u k, A. O l e c h and M. Nale zÇ y t y Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland e-mail:(is,olech,nalezyty)@sirius.astrouw.edu.pl Received December 1, 1995 ABSTRACT We report on CCD photometry of Nova V1500 Cygni obtained in July 1995 to show that twenty years after outburst, being of about 18 mag, the star can still be observed with small telescopes. The 0.1396 day period continues to be stable. Key words: Stars: individual: V1500 Cyg ± binaries: close ± novae, cataclysmic variables 1. Introduction V1500 Cygni (Nova Cygni 1975), the brightest, fastest and the most intriguing nova of the last twenty years, faded now to 18 mag. However, despite of its faint- ness, it still appears to be an object suitable for observations with small telescopes, and this is possible due to the CCD technique. The nova is still worthwhile to be observed. Twelve years after its outburst, polarimetric observations (Stockman, Schmidt and Lamb 1988) revealed that the object was an intermediate polar with the spin period Pspin of its white dwarf component being about 2% shorter than the orbital period Porb equal to 0.1396 days. Subsequently, the spin period appeared to be increasing (Schmidt and Stockman 1991, Schmidt, Liebert and Stockman 1995) with the rate of increase indicating synchronization of the rotational and orbital motions in about 170 years. On this time-scale the star will be returning to its pre-outburst AM Herculis state. -
Astrophysics in 2006 3
ASTROPHYSICS IN 2006 Virginia Trimble1, Markus J. Aschwanden2, and Carl J. Hansen3 1 Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575, Las Cumbres Observatory, Santa Barbara, CA: ([email protected]) 2 Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory, Organization ADBS, Building 252, 3251 Hanover Street, Palo Alto, CA 94304: ([email protected]) 3 JILA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder CO 80309: ([email protected]) Received ... : accepted ... Abstract. The fastest pulsar and the slowest nova; the oldest galaxies and the youngest stars; the weirdest life forms and the commonest dwarfs; the highest energy particles and the lowest energy photons. These were some of the extremes of Astrophysics 2006. We attempt also to bring you updates on things of which there is currently only one (habitable planets, the Sun, and the universe) and others of which there are always many, like meteors and molecules, black holes and binaries. Keywords: cosmology: general, galaxies: general, ISM: general, stars: general, Sun: gen- eral, planets and satellites: general, astrobiology CONTENTS 1. Introduction 6 1.1 Up 6 1.2 Down 9 1.3 Around 10 2. Solar Physics 12 2.1 The solar interior 12 2.1.1 From neutrinos to neutralinos 12 2.1.2 Global helioseismology 12 2.1.3 Local helioseismology 12 2.1.4 Tachocline structure 13 arXiv:0705.1730v1 [astro-ph] 11 May 2007 2.1.5 Dynamo models 14 2.2 Photosphere 15 2.2.1 Solar radius and rotation 15 2.2.2 Distribution of magnetic fields 15 2.2.3 Magnetic flux emergence rate 15 2.2.4 Photospheric motion of magnetic fields 16 2.2.5 Faculae production 16 2.2.6 The photospheric boundary of magnetic fields 17 2.2.7 Flare prediction from photospheric fields 17 c 2008 Springer Science + Business Media. -
Arxiv:0908.2624V1 [Astro-Ph.SR] 18 Aug 2009
Astronomy & Astrophysics Review manuscript No. (will be inserted by the editor) Accurate masses and radii of normal stars: Modern results and applications G. Torres · J. Andersen · A. Gim´enez Received: date / Accepted: date Abstract This paper presents and discusses a critical compilation of accurate, fun- damental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94 eclipsing systems, and α Centauri) that satisfy our criterion that the mass and radius of both stars be known to ±3% or better. All are non-interacting systems, so the stars should have evolved as if they were single. This sample more than doubles that of the earlier similar review by Andersen (1991), extends the mass range at both ends and, for the first time, includes an extragalactic binary. In every case, we have examined the original data and recomputed the stellar parameters with a consistent set of assumptions and physical constants. To these we add interstellar reddening, effective temperature, metal abundance, rotational velocity and apsidal motion determinations when available, and we compute a number of other physical parameters, notably luminosity and distance. These accurate physical parameters reveal the effects of stellar evolution with un- precedented clarity, and we discuss the use of the data in observational tests of stellar evolution models in some detail. Earlier findings of significant structural differences between moderately fast-rotating, mildly active stars and single stars, ascribed to the presence of strong magnetic and spot activity, are confirmed beyond doubt. We also show how the best data can be used to test prescriptions for the subtle interplay be- tween convection, diffusion, and other non-classical effects in stellar models. -
Nova V4743 Sagittarii 2002: an Intermediate Polar Candidate
Draft version March 30, 2021 A Preprint typeset using LTEX style emulateapj v. 6/22/04 NOVA V4743 SAGITTARII 2002: AN INTERMEDIATE POLAR CANDIDATE Tae W. Kang1, Alon Retter1, Alex Liu2, and Mercedes Richards1 1Dept. of Astronomy & Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802; [email protected]; [email protected]; [email protected] and 2Norcape Observatory, PO Box 300, Exmouth, 6707, Australia; [email protected] Draft version March 30, 2021 ABSTRACT We present the results of 11 nights of CCD unfiltered photometry of V4743 Sgr (Nova Sgr 2002 # 3) from 2003 and 2005. We find two periods of 0.2799 d ≈ 6.7 h and 0.01642 d ≈ 24 min in the 2005 data. The long period is also present in the 2003 data, but only weak evidence of the shorter period is found in this year. The 24-min period is somewhat longer than the 22-min period, which was detected from X-ray observations. We suggest that the 6.7-h periodicity represents the orbital period of the underlying binary system and that the 24-min period is the beat periodicity between the orbital period and the X-ray period, which is presumably the spin period of the white dwarf. Thus, V4743 Sgr should be classified as an intermediate polar (DQ Her star). About six months after the nova outburst, the optical light curve of V4743 Sgr seemed to show quasi-periodic oscillations, which are typical of the transient phase in classical nova. Therefore, our results support the previous suggestion that the transition phase in novae may be related to intermediate polars. -
GEORGE HERBIG and Early Stellar Evolution
GEORGE HERBIG and Early Stellar Evolution Bo Reipurth Institute for Astronomy Special Publications No. 1 George Herbig in 1960 —————————————————————– GEORGE HERBIG and Early Stellar Evolution —————————————————————– Bo Reipurth Institute for Astronomy University of Hawaii at Manoa 640 North Aohoku Place Hilo, HI 96720 USA . Dedicated to Hannelore Herbig c 2016 by Bo Reipurth Version 1.0 – April 19, 2016 Cover Image: The HH 24 complex in the Lynds 1630 cloud in Orion was discov- ered by Herbig and Kuhi in 1963. This near-infrared HST image shows several collimated Herbig-Haro jets emanating from an embedded multiple system of T Tauri stars. Courtesy Space Telescope Science Institute. This book can be referenced as follows: Reipurth, B. 2016, http://ifa.hawaii.edu/SP1 i FOREWORD I first learned about George Herbig’s work when I was a teenager. I grew up in Denmark in the 1950s, a time when Europe was healing the wounds after the ravages of the Second World War. Already at the age of 7 I had fallen in love with astronomy, but information was very hard to come by in those days, so I scraped together what I could, mainly relying on the local library. At some point I was introduced to the magazine Sky and Telescope, and soon invested my pocket money in a subscription. Every month I would sit at our dining room table with a dictionary and work my way through the latest issue. In one issue I read about Herbig-Haro objects, and I was completely mesmerized that these objects could be signposts of the formation of stars, and I dreamt about some day being able to contribute to this field of study.