1
|
Zimmerman EA, Irani I, Chen P, Gal-Yam A, Schulze S, Perley DA, Sollerman J, Filippenko AV, Shenar T, Yaron O, Shahaf S, Bruch RJ, Ofek EO, De Cia A, Brink TG, Yang Y, Vasylyev SS, Ben Ami S, Aubert M, Badash A, Bloom JS, Brown PJ, De K, Dimitriadis G, Fransson C, Fremling C, Hinds K, Horesh A, Johansson JP, Kasliwal MM, Kulkarni SR, Kushnir D, Martin C, Matuzewski M, McGurk RC, Miller AA, Morag J, Neil JD, Nugent PE, Post RS, Prusinski NZ, Qin Y, Raichoor A, Riddle R, Rowe M, Rusholme B, Sfaradi I, Sjoberg KM, Soumagnac M, Stein RD, Strotjohann NL, Terwel JH, Wasserman T, Wise J, Wold A, Yan L, Zhang K. The complex circumstellar environment of supernova 2023ixf. Nature 2024; 627:759-762. [PMID: 38538936 DOI: 10.1038/s41586-024-07116-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 01/24/2024] [Indexed: 04/01/2024]
Abstract
The early evolution of a supernova (SN) can reveal information about the environment and the progenitor star. When a star explodes in vacuum, the first photons to escape from its surface appear as a brief, hours-long shock-breakout flare1,2, followed by a cooling phase of emission. However, for stars exploding within a distribution of dense, optically thick circumstellar material (CSM), the first photons escape from the material beyond the stellar edge and the duration of the initial flare can extend to several days, during which the escaping emission indicates photospheric heating3. Early serendipitous observations2,4 that lacked ultraviolet (UV) data were unable to determine whether the early emission is heating or cooling and hence the nature of the early explosion event. Here we report UV spectra of the nearby SN 2023ixf in the galaxy Messier 101 (M101). Using the UV data as well as a comprehensive set of further multiwavelength observations, we temporally resolve the emergence of the explosion shock from a thick medium heated by the SN emission. We derive a reliable bolometric light curve that indicates that the shock breaks out from a dense layer with a radius substantially larger than typical supergiants.
Collapse
Affiliation(s)
- E A Zimmerman
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel.
| | - I Irani
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - P Chen
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - A Gal-Yam
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - S Schulze
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, Stockholm, Sweden
| | - D A Perley
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - J Sollerman
- The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, Stockholm, Sweden
| | - A V Filippenko
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - T Shenar
- Departamento de Astrofísica, Centro de Astrobiología (CSIC-INTA), Madrid, Spain
| | - O Yaron
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - S Shahaf
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - R J Bruch
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
- School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel
| | - E O Ofek
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - A De Cia
- European Southern Observatory, Garching bei München, Germany
- Department of Astronomy, University of Geneva, Versoix, Switzerland
| | - T G Brink
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - Y Yang
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
- Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing, China
| | - S S Vasylyev
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - S Ben Ami
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - M Aubert
- Université Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand, France
| | - A Badash
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - J S Bloom
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - P J Brown
- Department of Physics and Astronomy, Texas A&M University, College Station, TX, USA
| | - K De
- MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA, USA
| | - G Dimitriadis
- School of Physics, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland
| | - C Fransson
- The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, Stockholm, Sweden
| | - C Fremling
- Caltech Optical Observatories, California Institute of Technology, Pasadena, CA, USA
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - K Hinds
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - A Horesh
- The Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - J P Johansson
- The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, Stockholm, Sweden
| | - M M Kasliwal
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - S R Kulkarni
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - D Kushnir
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - C Martin
- Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA
| | - M Matuzewski
- Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA
| | - R C McGurk
- W. M. Keck Observatory, Kamuela, HI, USA
| | - A A Miller
- Department of Physics and Astronomy, Northwestern University, Evanston, IL, USA
- Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Northwestern University, Evanston, IL, USA
| | - J Morag
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - J D Neil
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - P E Nugent
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - R S Post
- Post Observatory, Lexington, MA, USA
| | - N Z Prusinski
- Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA, USA
| | - Y Qin
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - A Raichoor
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - R Riddle
- Caltech Optical Observatories, California Institute of Technology, Pasadena, CA, USA
| | - M Rowe
- Department of Physics and Astronomy, Texas A&M University, College Station, TX, USA
| | - B Rusholme
- IPAC, California Institute of Technology, Pasadena, CA, USA
| | - I Sfaradi
- The Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - K M Sjoberg
- Department of Astronomy, Harvard University, Cambridge, MA, USA
- Isaac Newton Group (ING), Santa Cruz de La Palma, Canary Islands, Spain
| | - M Soumagnac
- Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Physics, Bar-Ilan University, Ramat Gan, Israel
| | - R D Stein
- Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - N L Strotjohann
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - J H Terwel
- School of Physics, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland
- Isaac Newton Group (ING), Santa Cruz de La Palma, Canary Islands, Spain
| | - T Wasserman
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - J Wise
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - A Wold
- IPAC, California Institute of Technology, Pasadena, CA, USA
| | - L Yan
- Caltech Optical Observatories, California Institute of Technology, Pasadena, CA, USA
| | - K Zhang
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
- Department of Astronomy & Astrophysics, University of California, San Diego, La Jolla, CA, USA
| |
Collapse
|
2
|
Gorski C, Riddle R, Toporik H, Da Z, Dobson Z, Williams D, Mazor Y. The structure of the Physcomitrium patens photosystem I reveals a unique Lhca2 paralogue replacing Lhca4. Nat Plants 2022; 8:307-316. [PMID: 35190662 DOI: 10.1038/s41477-022-01099-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 01/11/2022] [Indexed: 05/10/2023]
Abstract
The moss Physcomitrium patens diverged from green algae shortly after the colonization of land by ancient plants. This colonization posed new environmental challenges, which drove evolutionary processes. The photosynthetic machinery of modern flowering plants is adapted to the high light conditions on land. Red-shifted Lhca4 antennae are present in the photosystem I light-harvesting complex of many green-lineage plants but absent in P. patens. The cryo-EM structure of the P. patens photosystem I light-harvesting complex I supercomplex (PSI-LHCI) at 2.8 Å reveals that Lhca4 is replaced by a unique Lhca2 paralogue in moss. This PSI-LHCI supercomplex also retains the PsaM subunit, present in Cyanobacteria and several algal species but lost in vascular plants, and the PsaO subunit responsible for binding light-harvesting complex II. The blue-shifted Lhca2 paralogue and chlorophyll b enrichment relative to flowering plants make the P. patens PSI-LHCI spectroscopically unique among other green-lineage supercomplexes. Overall, the structure represents an evolutionary intermediate PSI with the crescent-shaped LHCI common in vascular plants, and contains a unique Lhca2 paralogue that facilitates the moss's adaptation to low-light niches.
Collapse
Affiliation(s)
- C Gorski
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, USA
| | - R Riddle
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, USA
| | - H Toporik
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, USA
| | - Z Da
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, USA
| | - Z Dobson
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, USA
| | - D Williams
- John M. Cowley Center for High Resolution Electron Microscopy, Arizona State University, Tempe, AZ, USA
| | - Y Mazor
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA.
- Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, USA.
| |
Collapse
|
3
|
Gal-Yam A, Bruch R, Schulze S, Yang Y, Perley DA, Irani I, Sollerman J, Kool EC, Soumagnac MT, Yaron O, Strotjohann NL, Zimmerman E, Barbarino C, Kulkarni SR, Kasliwal MM, De K, Yao Y, Fremling C, Yan L, Ofek EO, Fransson C, Filippenko AV, Zheng W, Brink TG, Copperwheat CM, Foley RJ, Brown J, Siebert M, Leloudas G, Cabrera-Lavers AL, Garcia-Alvarez D, Marante-Barreto A, Frederick S, Hung T, Wheeler JC, Vinkó J, Thomas BP, Graham MJ, Duev DA, Drake AJ, Dekany R, Bellm EC, Rusholme B, Shupe DL, Andreoni I, Sharma Y, Riddle R, van Roestel J, Knezevic N. A WC/WO star exploding within an expanding carbon-oxygen-neon nebula. Nature 2022; 601:201-204. [PMID: 35022591 DOI: 10.1038/s41586-021-04155-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 10/15/2021] [Indexed: 11/09/2022]
Abstract
The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars1 emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion4. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.
Collapse
Affiliation(s)
- A Gal-Yam
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel.
| | - R Bruch
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - S Schulze
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel.,The Oskar Klein Centre, Department of Astronomy and Department of Physics, AlbaNova, Stockholm University, Stockholm, Sweden
| | - Y Yang
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel.,Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - D A Perley
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - I Irani
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - J Sollerman
- The Oskar Klein Centre, Department of Astronomy and Department of Physics, AlbaNova, Stockholm University, Stockholm, Sweden
| | - E C Kool
- The Oskar Klein Centre, Department of Astronomy and Department of Physics, AlbaNova, Stockholm University, Stockholm, Sweden
| | - M T Soumagnac
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel.,Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - O Yaron
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - N L Strotjohann
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - E Zimmerman
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - C Barbarino
- The Oskar Klein Centre, Department of Astronomy and Department of Physics, AlbaNova, Stockholm University, Stockholm, Sweden
| | - S R Kulkarni
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - M M Kasliwal
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - K De
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - Y Yao
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - C Fremling
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - L Yan
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - E O Ofek
- Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, Israel
| | - C Fransson
- The Oskar Klein Centre, Department of Astronomy and Department of Physics, AlbaNova, Stockholm University, Stockholm, Sweden
| | - A V Filippenko
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA.,Miller Institute for Basic Research in Science, University of California, Berkeley, Berkeley, CA, USA
| | - W Zheng
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - T G Brink
- Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA
| | - C M Copperwheat
- Astrophysics Research Institute, Liverpool John Moores University, Liverpool, UK
| | - R J Foley
- Department of Astronomy and Astrophysics, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - J Brown
- Department of Astronomy and Astrophysics, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - M Siebert
- Department of Astronomy and Astrophysics, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - G Leloudas
- DTU Space, National Space Institute, Technical University of Denmark, Kongens Lyngby, Denmark
| | | | | | | | - S Frederick
- Department of Astronomy, University of Maryland, College Park, MD, USA
| | - T Hung
- Department of Astronomy and Astrophysics, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - J C Wheeler
- Department of Astronomy, University of Texas at Austin, Austin, TX, USA
| | - J Vinkó
- Department of Astronomy, University of Texas at Austin, Austin, TX, USA.,Konkoly Observatory, ELKH CSFK, Budapest, Hungary.,Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary.,ELTE Institute of Physics, Eötvös Loránd University, Budapest, Hungary
| | - B P Thomas
- Department of Astronomy, University of Texas at Austin, Austin, TX, USA
| | - M J Graham
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - D A Duev
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - A J Drake
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - R Dekany
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - E C Bellm
- DIRAC Institute, Department of Astronomy, University of Washington, Seattle, WA, USA
| | - B Rusholme
- IPAC, California Institute of Technology, Pasadena, CA, USA
| | - D L Shupe
- IPAC, California Institute of Technology, Pasadena, CA, USA
| | - I Andreoni
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - Y Sharma
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - R Riddle
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - J van Roestel
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA, USA
| | - N Knezevic
- Department of Astronomy, Faculty of Mathematics, University of Belgrade, Belgrade, Serbia
| |
Collapse
|
4
|
Campante TL, Barclay T, Swift JJ, Huber D, Adibekyan VZ, Cochran W, Burke CJ, Isaacson H, Quintana EV, Davies GR, Silva Aguirre V, Ragozzine D, Riddle R, Baranec C, Basu S, Chaplin WJ, Christensen-Dalsgaard J, Metcalfe TS, Bedding TR, Handberg R, Stello D, Brewer JM, Hekker S, Karoff C, Kolbl R, Law NM, Lundkvist M, Miglio A, Rowe JF, Santos NC, Van Laerhoven C, Arentoft T, Elsworth YP, Fischer DA, Kawaler SD, Kjeldsen H, Lund MN, Marcy GW, Sousa SG, Sozzetti A, White TR. KOI-3158: The oldest known system of terrestrial-size planets. EPJ Web of Conferences 2015. [DOI: 10.1051/epjconf/201510102004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
5
|
Travouillon T, Otarola A, Els S, Riddle R, Schöck M, Skidmore W, Bibb D. Accurate measurements of Optical Turbulence with Sonic- anemometers. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/1742-6596/595/1/012036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
6
|
Campante TL, Barclay T, Swift JJ, Huber D, Adibekyan VZ, Cochran W, Burke CJ, Isaacson H, Quintana EV, Davies GR, Silva Aguirre V, Ragozzine D, Riddle R, Baranec C, Basu S, Chaplin WJ, Christensen-Dalsgaard J, Metcalfe TS, Bedding TR, Handberg R, Stello D, Brewer JM, Hekker S, Karoff C, Kolbl R, Law NM, Lundkvist M, Miglio A, Rowe JF, Santos NC, Van Laerhoven C, Arentoft T, Elsworth YP, Fischer DA, Kawaler SD, Kjeldsen H, Lund MN, Marcy GW, Sousa SG, Sozzetti A, White TR. AN ANCIENT EXTRASOLAR SYSTEM WITH FIVE SUB-EARTH-SIZE PLANETS. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/799/2/170] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
7
|
Els SG, Schöck M, Seguel J, Tokovinin A, Kornilov V, Riddle R, Skidmore W, Travouillon T, Vogiatzis K, Blum R, Bustos E, Gregory B, Vasquez J, Walker D, Gillett P. Study on the precision of the multiaperture scintillation sensor turbulence profiler (MASS) employed in the site testing campaign for the Thirty Meter Telescope. Appl Opt 2008; 47:2610-2618. [PMID: 18470256 DOI: 10.1364/ao.47.002610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The multiaperture scintillation sensor (MASS) has become a device widely employed to measure the altitude distribution of atmospheric turbulence. An empirical study is reported that investigates the dependence of the MASS results on the knowledge of the instrumental parameters. Also, the results of a side-by-side comparison of two MASS instruments are presented, indicating that MASS instruments permit measurements of the integrated seeing to a precision better than 0.05 arc sec and of the individual turbulence layer strength C(n)(2)(h)dh to better than 10(-14) m(1/3).
Collapse
Affiliation(s)
- S G Els
- Cerro Tololo Inter-American Observatory, Casilla, La Serena, Chile.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
|
9
|
Silvotti R, Schuh S, Janulis R, Solheim JE, Bernabei S, Østensen R, Oswalt TD, Bruni I, Gualandi R, Bonanno A, Vauclair G, Reed M, Chen CW, Leibowitz E, Paparo M, Baran A, Charpinet S, Dolez N, Kawaler S, Kurtz D, Moskalik P, Riddle R, Zola S. A giant planet orbiting the ‘extreme horizontal branch’ star V 391 Pegasi. Nature 2007; 449:189-91. [PMID: 17851517 DOI: 10.1038/nature06143] [Citation(s) in RCA: 202] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2007] [Accepted: 07/26/2007] [Indexed: 11/09/2022]
Abstract
After the initial discoveries fifteen years ago, over 200 extrasolar planets have now been detected. Most of them orbit main-sequence stars similar to our Sun, although a few planets orbiting red giant stars have been recently found. When the hydrogen in their cores runs out, main-sequence stars undergo an expansion into red-giant stars. This expansion can modify the orbits of planets and can easily reach and engulf the inner planets. The same will happen to the planets of our Solar System in about five billion years and the fate of the Earth is matter of debate. Here we report the discovery of a planetary-mass body (Msini = 3.2M(Jupiter)) orbiting the star V 391 Pegasi at a distance of about 1.7 astronomical units (au), with a period of 3.2 years. This star is on the extreme horizontal branch of the Hertzsprung-Russell diagram, burning helium in its core and pulsating. The maximum radius of the red-giant precursor of V 391 Pegasi may have reached 0.7 au, while the orbital distance of the planet during the stellar main-sequence phase is estimated to be about 1 au. This detection of a planet orbiting a post-red-giant star demonstrates that planets with orbital distances of less than 2 au can survive the red-giant expansion of their parent stars.
Collapse
Affiliation(s)
- R Silvotti
- INAF-Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131 Napoli, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Ways K, Riddle R, Ways M, Cook P. Effect of phorbol esters on cytosolic protein kinase C content and activity in the human monoblastoid U937 cell. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(17)35309-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
|
11
|
Pettigrew J, Roberts D, Riddle R, Udupa J, Collier D, Ram C. Identification of an anteriorly displaced meniscus in vitro by means of three-dimensional image reconstructions. Oral Surg Oral Med Oral Pathol 1985; 59:535-42. [PMID: 3859814 DOI: 10.1016/0030-4220(85)90099-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Computerized tomography has some limitations for diagnosis of internal derangements of the TMJ. The use of three-dimensional image reconstructions of CT data may enhance the diagnostic utility of CT. In a cadaver simulation, three-dimensional imaging was able to demonstrate the location of a displaced meniscus which was not obvious in two-dimensional sections. Location of the meniscus was aided by the use of a "transparency mode" in displaying the data.
Collapse
|
12
|
|