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New Herbig±Haro Objects and Giant Outflows in Orion
Mon. Not. R. Astron. Soc. 310, 331±354 (1999) New Herbig±Haro objects and giant outflows in Orion S. L. Mader,1 W. J. Zealey,1 Q. A. Parker2 and M. R. W. Masheder3,4 1Department of Engineering Physics, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia 2Anglo-Australian Observatory, Coonabarabran, NSW 2357, Australia 3Department of Physics, University of Bristol, Bristol BS8 1TL 4Netherlands Foundation for Research in Astronomy, PO Box 2, 7990 AA Dwingeloo, the Netherlands Accepted 1999 June 29. Received 1999 May 11; in original form 1998 June 25 ABSTRACT We present the results of a photographic and CCD imaging survey for Herbig±Haro (HH) objects in the L1630 and L1641 giant molecular clouds in Orion. The new HH flows were initially identified from a deep Ha film from the recently commissioned AAO/UKST Ha Survey of the southern sky. Our scanned Ha and broad-band R images highlight both the improved resolution of the Ha survey and the excellent contrast of the Ha flux with respect to the broad-band R. Comparative IVN survey images allow us to distinguish between emission and reflection nebulosity. Our CCD Ha,[Sii], continuum and I-band images confirm the presence of a parsec-scale HH flow associated with the Ori I-2 cometary globule, and several parsec-scale strings of HH emission centred on the L1641-N infrared cluster. Several smaller outflows display one-sided jets. Our results indicate that, for declinations south of 268 in L1641, parsec-scale flows appear to be the major force in the large-scale movement of optical dust and molecular gas. -
SHAPING the WIND of DYING STARS Noam Soker
Pleasantness Review* Department of Physics, Technion, Israel The role of jets in the common envelope evolution (CEE) and in the grazing envelope evolution (GEE) Cambridge 2016 Noam Soker •Dictionary translation of my name from Hebrew to English (real!): Noam = Pleasantness Soker = Review A short summary JETS See review accepted for publication by astro-ph in May 2016: Soker, N., 2016, arXiv: 160502672 A very short summary JFM See review accepted for publication by astro-ph in May 2016: Soker, N., 2016, arXiv: 160502672 A full summary • Jets are unavoidable when the companion enters the common envelope. They are most likely to continue as the secondary star enters the envelop, and operate under a negative feedback mechanism (the Jet Feedback Mechanism - JFM). • Jets: Can be launched outside and Secondary inside the envelope star RGB, AGB, Red Giant Massive giant primary star Jets Jets Jets: And on its surface Secondary star RGB, AGB, Red Giant Massive giant primary star Jets A full summary • Jets are unavoidable when the companion enters the common envelope. They are most likely to continue as the secondary star enters the envelop, and operate under a negative feedback mechanism (the Jet Feedback Mechanism - JFM). • When the jets mange to eject the envelope outside the orbit of the secondary star, the system avoids a common envelope evolution (CEE). This is the Grazing Envelope Evolution (GEE). Points to consider (P1) The JFM (jet feedback mechanism) is a negative feedback cycle. But there is a positive ingredient ! In the common envelope evolution (CEE) more mass is removed from zones outside the orbit. -
A Massive Bipolar Outflow and a Dusty Torus with Large Grains in the Preplanetary Nebula Iras 22036+5306 R
The Astrophysical Journal, 653:1241Y1252, 2006 December 20 # 2006. The American Astronomical Society. All rights reserved. Printed in U.S.A. A MASSIVE BIPOLAR OUTFLOW AND A DUSTY TORUS WITH LARGE GRAINS IN THE PREPLANETARY NEBULA IRAS 22036+5306 R. Sahai,1 K. Young,2 N. A. Patel,2 C. Sa´nchez Contreras,3 and M. Morris4 Received 2006 June 19; accepted 2006 August 10 ABSTRACT We report high angular resolution (100)COJ ¼ 3Y2 interferometric mapping using the Submillimeter Array (SMA) of IRAS 22036+5306 (I22036), a bipolar preplanetary nebula (PPN) with knotty jets discovered in our HST snapshot survey of young PPNs. In addition, we have obtained supporting lower resolution (1000) CO and 13CO J ¼ 1Y0 observations with the Owens Valley Radio Observatory (OVRO) interferometer, as well as optical long-slit echelle spectra at the Palomar Observatory. The CO J ¼ 3Y2 observations show the presence of a very fast (220 km sÀ1), 39 À1 highly collimated, massive (0.03 M ) bipolar outflow with a very large scalar momentum (about 10 gcms ), and the characteristic spatiokinematic structure of bow shocks at the tips of this outflow. The H line shows an absorption feature blueshifted from the systemic velocity by 100 km sÀ1, which most likely arises in neutral interface material between the fast outflow and the dense walls of the bipolar lobes at low latitudes. The fast outflow in I22036, as in most PPNs, cannot be driven by radiation pressure. We find an unresolved source of submillimeter (and millimeter- wave) continuum emission in I22036, implying a very substantial mass (0.02Y0.04 M ) of large (radius k1 mm), cold (P50 K) dust grains associated with I22036’s toroidal waist. -
Jsolated Stars of Low Metallicity
galaxies Article Jsolated Stars of Low Metallicity Efrat Sabach Department of Physics, Technion—Israel Institute of Technology, Haifa 32000, Israel; [email protected] Received: 15 July 2018; Accepted: 9 August 2018; Published: 15 August 2018 Abstract: We study the effects of a reduced mass-loss rate on the evolution of low metallicity Jsolated stars, following our earlier classification for angular momentum (J) isolated stars. By using the stellar evolution code MESA we study the evolution with different mass-loss rate efficiencies for stars with low metallicities of Z = 0.001 and Z = 0.004, and compare with the evolution with solar metallicity, Z = 0.02. We further study the possibility for late asymptomatic giant branch (AGB)—planet interaction and its possible effects on the properties of the planetary nebula (PN). We find for all metallicities that only with a reduced mass-loss rate an interaction with a low mass companion might take place during the AGB phase of the star. The interaction will most likely shape an elliptical PN. The maximum post-AGB luminosities obtained, both for solar metallicity and low metallicities, reach high values corresponding to the enigmatic finding of the PN luminosity function. Keywords: late stage stellar evolution; planetary nebulae; binarity; stellar evolution 1. Introduction Jsolated stars are stars that do not gain much angular momentum along their post main sequence evolution from a companion, either stellar or substellar, thus resulting with a lower mass-loss rate compared to non-Jsolated stars [1]. As previously stated in Sabach and Soker [1,2], the fitting formulae of the mass-loss rates for red giant branch (RGB) and asymptotic giant branch (AGB) single stars are set empirically by contaminated samples of stars that are classified as “single stars” but underwent an interaction with a companion early on, increasing the mass-loss rate to the observed rates. -
VLBI Monitoring Observations of Water Masers Around the Semi
VLBI Monitoring Observations of Water Masers Around the Semi-Regular Variable Star R Crateris Jos´eK. Ishitsuka ,1 Hiroshi Imai,2,3 Toshihiro Omodaka,4 Munetaka Ueno,1 Osamu Kameya,2,3 Tetsuo Sasao,3 Masaki Morimoto,5 Takeshi Miyaji,3,6 Jun-ichi Nakajima,7 and Teruhiko Watanabe4 1Department of Earth Science and Astronomy, University of Tokyo, Komaba, Tokyo 153-8902 [email protected] 2Mizusawa Astrogeodynamics Observatory, National Astronomical Observatory, Mizusawa, Iwate 023-0861 3VERA Project Office, National Astronomical Observatory, Mitaka, Tokyo 181-8588 4Faculty of Science, Kagoshima University, Kagoshima, Kagoshima 890-0065 5Nishi-Harima Astronomical Observatory, Sayo, Hyogo 679-5313 6Nobeyama Radio Observatory, National Astronomical Observatory, Minamisaku, Nagano 384-1305 7Kashima Space Research Center, Communications Research Laboratory, Kashima, Ibaraki 314-0012 (Received 2000 December 8; accepted 2001 September 24) Abstract We monitored water-vapor masers around the semi-regular variable star R Crateris with the Japanese VLBI Network (J-Net) at the 22 GHz band during four epochs with intervals of one month. The relative proper motions and Doppler- velocity drifts of twelve maser features were measured. Most of them existed for longer than 80 days. The 3-D kinematics of the features indicates a bipolar expanding flow. The major axis of the asymmetric flow was estimated to be at P.A. = 136◦. The existence of a bipolar outflow suggests that a Mira variable star had already formed a bipolar outflow. The water masers are in a region of apparent minimum radii of arXiv:astro-ph/0112302v1 13 Dec 2001 1.3 × 1012 m and maximum radii of 2.6 × 1012 m, between which the expansion ve- locity ranges from 4.3 to 7.4 km s−1. -
NOAM SOKER Date: August, 2012
Name: NOAM SOKER Date: August, 2012 RESUME PERSONAL DETAILS Name: Noam Soker Place and Date of Birth: Israel, 2.9.1958 Marital Status: Married + 3 Citizenship and Identity Card Number: 55299275, Israel Permanent Home Address: Shimshit, Israel Telephone Number: 054-5925995 Office Address and Phone: Department of Physics Technion , Haifa 32000, Israel Tel.: 04-8293858 Chair: Charles Wolfson Academic Chair Electronic Address: [email protected] Telefax Number: 04-8295755 ACADEMIC DEGREES Dates Name of Institution and Degree Department 1975-1977 Department of Mathematics Beginning of Bachelor Degree and Physics, Oranim, in Physics University of Haifa 1980-1982 Department of Physics, Finishing Bachelor in Physics Technion B.Sc. awarded: 4th May 1983 – Summa Cum Laude 1982-1986 Department of Physics, Doctoral studies Technion Ph.D. awarded: 20th April 1986 2 ACADEMIC APPOINTMENTS Dates Name of Institution and Department Rank July-August 1984 Astronomical Institute, University of Visiting Amsterdam, Amsterdam – Holland Researcher September 1986 - Department of Astronomy, University of Post-doctoral August 1989 Virginia, Charlottesville, Virginia, U.S.A. September 1989 - Harvard-Smithsonian Center for Astrophysics, Post-doctoral September 1992 Harvard University, Cambridge, MA, U.S.A. October 1992 - Oranim - University of Haifa, Science Education Senior May 1994 Department Lecturer May 1994 - Oranim - University of Haifa, Science Education Associate December 1998 Department Professor December 1998- Oranim - University of Haifa, Science Education Full Professor September 2003 Department October 2003 Department of Physics, Technion Full Professor PROFESSIONAL EXPERIENCE October 1994 - October 1998 Chairman of the Mathematics-Physics Department, Oranim - University of Haifa May 2005 - September 2009 Head of the undergraduate program at the Physics Dept. -
The Origin of Nonradiative Heating/Momentum in Hot Stars
NASA Conference Publication 2358 NASA-CP-2358 19850009446 The Origin of Nonradiative Heating/Momentum in Hot Stars Proceedings of a workshop held at NASA Goddard Space Flight Center Greenbelt, Maryland June 5-7, 1984 NI_SA NASA Conference Publication 2358 The Origin of Nonradiative Heating/Momentum in Hot Stars Edited by A. B. Underhill and A. G. Michalitsianos Goddard Space Flight Center Greenbelt, Maryland Proceedings of a workshop sponsored by the National Aeronautics and Space Administration, Washington, D.C., and the American Astronomical Society, Washington, D.C., and held at NASA Goddard Space Flight Center Greenbelt, Maryland June 5-7, 1984 N/LS/X NationalAeronautics and SpaceAdministration ScientificandTechnical InformationBranch J 1985 TABLE OF CONTENTS ORGANIZING COMMITTEE v LIST OF PARTICIPANTS vi OPENING REMARKS A.B. Underhill I SESSION I. - EVIDENCE FOR NONRADIATIVE ACTIVITY IN STARS EVIDENCE FOR NONRADIATIVE ACTIVITY IN HOT STARS J.P. Cassinelli (Invited review) 2 EVIDENCE FOR NON-RADIATIVE ACTIVITY IN STARS WITH Tef f < i0,000 K Jeffrey L. Linsky (Invited review) 24 OBSERVATIONS OF NONTHERMAL RADIO EMISSION FROM EARLY TYPE STARS D.C. Abbott, J.H. Bieging and E. Churehwell 47 NONRADIAL PULSATION AND MASS LOSS IN EARLY B STARS G. Donald Penrod and Myron A. Smith 53 NARROW ABSORPTION COMPONENTS IN Be STAR WINDS C.A. Grady 57 LIGHT VARIATIONS OF THE B-TYPE STAR HD 160202 Gustav A. Bakos 62 ULTRAVIOLET SPECTRAL MORPHOLOGY OF 0-TYPE STELLAR WINDS Nolan R. Walborn 66 NONTHERMAL RADIO EMISSION AND THE HR DIAGRAM D.M. Gibson 70 X-RAY ACTIVITY IN PRE-MAIN SEQUENCE STARS Eric D. Feigelson 75 ACTIVE PHENOMENA IN THE PRE-MAIN SEQUENCE STAR AB AUR F. -
Abstracts of Talks 1
Abstracts of Talks 1 INVITED AND CONTRIBUTED TALKS (in order of presentation) Milky Way and Magellanic Cloud Surveys for Planetary Nebulae Quentin A. Parker, Macquarie University I will review current major progress in PN surveys in our own Galaxy and the Magellanic clouds whilst giving relevant historical context and background. The recent on-line availability of large-scale wide-field surveys of the Galaxy in several optical and near/mid-infrared passbands has provided unprecedented opportunities to refine selection techniques and eliminate contaminants. This has been coupled with surveys offering improved sensitivity and resolution, permitting more extreme ends of the PN luminosity function to be explored while probing hitherto underrepresented evolutionary states. Known PN in our Galaxy and LMC have been significantly increased over the last few years due primarily to the advent of narrow-band imaging in important nebula lines such as H-alpha, [OIII] and [SIII]. These PNe are generally of lower surface brightness, larger angular extent, in more obscured regions and in later stages of evolution than those in most previous surveys. A more representative PN population for in-depth study is now available, particularly in the LMC where the known distance adds considerable utility for derived PN parameters. Future prospects for Galactic and LMC PN research are briefly highlighted. Local Group Surveys for Planetary Nebulae Laura Magrini, INAF, Osservatorio Astrofisico di Arcetri The Local Group (LG) represents the best environment to study in detail the PN population in a large number of morphological types of galaxies. The closeness of the LG galaxies allows us to investigate the faintest side of the PN luminosity function and to detect PNe also in the less luminous galaxies, the dwarf galaxies, where a small number of them is expected. -
ALIGNMENT BETWEEN PROTOSTELLAR OUTFLOWS and FILAMENTARY STRUCTURE Ian W
Draft version July 27, 2017 Preprint typeset using LATEX style emulateapj v. 01/23/15 ALIGNMENT BETWEEN PROTOSTELLAR OUTFLOWS AND FILAMENTARY STRUCTURE Ian W. Stephens1, Michael M. Dunham2,1, Philip C. Myers1, Riwaj Pokhrel1,3, Sarah I. Sadavoy1, Eduard I. Vorobyov4,5,6, John J. Tobin7,8, Jaime E. Pineda9, Stella S. R. Offner3, Katherine I. Lee1, Lars E. Kristensen10, Jes K. Jørgensen11, Alyssa A. Goodman1, Tyler L. Bourke12,Hector´ G. Arce13, Adele L. Plunkett14 Draft version July 27, 2017 ABSTRACT We present new Submillimeter Array (SMA) observations of CO(2{1) outflows toward young, em- bedded protostars in the Perseus molecular cloud as part of the Mass Assembly of Stellar Systems and their Evolution with the SMA (MASSES) survey. For 57 Perseus protostars, we characterize the orientation of the outflow angles and compare them with the orientation of the local filaments as derived from Herschel observations. We find that the relative angles between outflows and filaments are inconsistent with purely parallel or purely perpendicular distributions. Instead, the observed dis- tribution of outflow-filament angles are more consistent with either randomly aligned angles or a mix of projected parallel and perpendicular angles. A mix of parallel and perpendicular angles requires perpendicular alignment to be more common by a factor of ∼3. Our results show that the observed distributions probably hold regardless of the protostar's multiplicity, age, or the host core's opacity. These observations indicate that the angular momentum axis of a protostar may be independent of the large-scale structure. We discuss the significance of independent protostellar rotation axes in the general picture of filament-based star formation. -
Irradiated Shocks in the W28 A2 Outflow
Irradiated shocks in the W28 A2 outflow Antoine Gusdorf, LERMA/LRA, Paris, France Maryvonne Gerin, LERMA/LRA, Paris, France Pierre Lesaffre, LERMA/LRA, Paris, France Javier Goicoechea, Centro de Astrobiología (CSIC/INTA), Madrid, Spain Nicolas Flagey, JPL, Pasadena, USA …and the PRISMAS Team 10/16/13 The Universe explored by Herschel, ESA/ESTEC, Noordwijk, The Netherlands, 15-18 October, 2013 1 What is the W28 A2 outflow ? Also known as “G5.89-00.39”, or the “Harvey & Forveille 1988” outflow Hunter et al. 2008 CO (1-0) 20 to 58 km s-1 CO (1-0) 0 to -37 km s-1 10/16/13 The Universe explored by Herschel, ESA/ESTEC, Noordwijk, The Netherlands, 15-18 October, 2013 2 Outline • MOTIVATIONS • THE STRUCTURE OF THE W28A2 REGION • CO OBSERVATIONS • C I & C+ OBSERVATIONS • PERSPECTIVES 10/16/13 The Universe explored by Herschel, ESA/ESTEC, Noordwijk, The Netherlands, 15-18 October, 2013 3 MOTIVATIONS 10/16/13 The Universe explored by Herschel, ESA/ESTEC, Noordwijk, The Netherlands, 15-18 October, 2013 4 Motivations: ISM & massive star formation • The massive star formation problem: How to form massive stars despite the radiation pressure ? . turbulent core model with a monolithic collapse scenario, scale-up of the low-mass scenario . highly dynamical competitive accretion model involving the formation of a cluster • The ISM insights: . Physical and chemical processes in a shocked environment . The shock is irradiated ; What is its environmental impact ? 10/16/13 The Universe explored by Herschel, ESA/ESTEC, Noordwijk, The Netherlands, 15-18 October, 2013 5 Motivations: the energetic balance of galaxies • CO ladders observations from external galaxies Large scale effects from PDR, XDR, and shock contributions NGC 253 Hailey-Dunsheath et al. -
The Agb Newsletter
THE AGB NEWSLETTER An electronic publication dedicated to Asymptotic Giant Branch stars and related phenomena Official publication of the IAU Working Group on Red Giants and Supergiants No. 286 — 2 May 2021 https://www.astro.keele.ac.uk/AGBnews Editors: Jacco van Loon, Ambra Nanni and Albert Zijlstra Editorial Board (Working Group Organising Committee): Marcelo Miguel Miller Bertolami, Carolyn Doherty, JJ Eldridge, Anibal Garc´ıa-Hern´andez, Josef Hron, Biwei Jiang, Tomasz Kami´nski, John Lattanzio, Emily Levesque, Maria Lugaro, Keiichi Ohnaka, Gioia Rau, Jacco van Loon (Chair) Editorial Dear Colleagues, It is our pleasure to present you the 286th issue of the AGB Newsletter. A healthy 30 postings are sure to keep you inspired. Now that the Leuven workshop has happened, we are gearing up to the IAU-sponsored GAPS 2021 virtual discussion meeting aimed to lay out a roadmap for cool evolved star research: we have got an exciting line-up of new talent as well as seasoned experts introducing the final session – all are encouraged to contribute to the meeting through 5-minute presentations or live discussion and the White Paper that will follow (see announcement at the back). Those interested in the common envelope process will no doubt consider attending the CEPO 2021 virtual meeting on this topic organised at the end of August / star of September. Great news on the job front: there are Ph.D. positions in Bordeaux, postdoc positions in Warsaw and another one in Nice. Thanks to Josef Hron and P´eter Abrah´am´ for ensuring the continuation of the Fizeau programme for exchange in the field of interferometry. -
Cycle 8 Approved Programs
Cycle 8 Approved Programs PI INSTITUTION COUNTRY PANEL TITLE Ajhar National Optical Astronomy Observatories United States CLUS Reconciling the SBF and SNIa Distance Scales Allen Space Telescope Science Institute United States ISM How Opaque Are Spiral Galaxies? Antonucci University of California Santa Barbara United States AGNH Optical Nuclear Hotspot in NGC 1068 Arav Institute of Geophysics and Planetary Physics United States AGNP Deep STIS Observations of BALQSO PG 0946+301 Armandroff Kitt Peak National Observatory United States FSP The Horizontal Branches of the M31 Dwarf Spheroidal Companions And V & VI Axon University of Manchester United Kingdom GSD The black hole versus bulge mass relationship in spiral galaxies Ayres University of Colorado United States CS Origins Structure and Evolution of Magnetic Activity in the Cool Half of the H-R Diagram: A STIS Survey Bagenal University of Colorado United States SS HST-Galileo Io Campaign Bailyn Yale University United States SPC High Precision Photometry of the Core of M13 Baker University of California Berkeley United States AGNP Absorption and obscuration in radio-loud quasars Baldwin Cerro Tololo Interamerican Observatory Chile AGNP High Abundances in Luminous Quasars: A Test Case Bally CASA University of Colorado Boulder United States SE Herbig-Haro Jets Irradiated by Massive OB Stars Bally University of Colorado Boulder United States YS The Structure and Kinematics of Irradiated Disks and Associated High Velocity Features in Orion Barstow University of Leicester United Kingdom HS THE