Stellar Life Cycle
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Spectroscopic Analysis of Accretion/Ejection Signatures in the Herbig Ae/Be Stars HD 261941 and V590 Mon T Moura, S
Spectroscopic analysis of accretion/ejection signatures in the Herbig Ae/Be stars HD 261941 and V590 Mon T Moura, S. Alencar, A. Sousa, E. Alecian, Y. Lebreton To cite this version: T Moura, S. Alencar, A. Sousa, E. Alecian, Y. Lebreton. Spectroscopic analysis of accretion/ejection signatures in the Herbig Ae/Be stars HD 261941 and V590 Mon. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2020, 494 (3), pp.3512-3535. 10.1093/mnras/staa695. hal-02523038 HAL Id: hal-02523038 https://hal.archives-ouvertes.fr/hal-02523038 Submitted on 16 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. MNRAS 000,1–24 (2019) Preprint 27 February 2020 Compiled using MNRAS LATEX style file v3.0 Spectroscopic analysis of accretion/ejection signatures in the Herbig Ae/Be stars HD 261941 and V590 Mon T. Moura1?, S. H. P. Alencar1, A. P. Sousa1;2, E. Alecian2, Y. Lebreton3;4 1Universidade Federal de Minas Gerais, Departamento de Física, Av. Antônio Carlos 6627, 31270-901, Brazil 2Univ. Grenoble Alpes, IPAG, F-38000 Grenoble, France 3LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. -
BRAS Newsletter August 2013
www.brastro.org August 2013 Next meeting Aug 12th 7:00PM at the HRPO Dark Site Observing Dates: Primary on Aug. 3rd, Secondary on Aug. 10th Photo credit: Saturn taken on 20” OGS + Orion Starshoot - Ben Toman 1 What's in this issue: PRESIDENT'S MESSAGE....................................................................................................................3 NOTES FROM THE VICE PRESIDENT ............................................................................................4 MESSAGE FROM THE HRPO …....................................................................................................5 MONTHLY OBSERVING NOTES ....................................................................................................6 OUTREACH CHAIRPERSON’S NOTES .........................................................................................13 MEMBERSHIP APPLICATION .......................................................................................................14 2 PRESIDENT'S MESSAGE Hi Everyone, I hope you’ve been having a great Summer so far and had luck beating the heat as much as possible. The weather sure hasn’t been cooperative for observing, though! First I have a pretty cool announcement. Thanks to the efforts of club member Walt Cooney, there are 5 newly named asteroids in the sky. (53256) Sinitiere - Named for former BRAS Treasurer Bob Sinitiere (74439) Brenden - Named for founding member Craig Brenden (85878) Guzik - Named for LSU professor T. Greg Guzik (101722) Pursell - Named for founding member Wally Pursell -
XIII Publications, Presentations
XIII Publications, Presentations 1. Refereed Publications E., Kawamura, A., Nguyen Luong, Q., Sanhueza, P., Kurono, Y.: 2015, The 2014 ALMA Long Baseline Campaign: First Results from Aasi, J., et al. including Fujimoto, M.-K., Hayama, K., Kawamura, High Angular Resolution Observations toward the HL Tau Region, S., Mori, T., Nishida, E., Nishizawa, A.: 2015, Characterization of ApJ, 808, L3. the LIGO detectors during their sixth science run, Classical Quantum ALMA Partnership, et al. including Asaki, Y., Hirota, A., Nakanishi, Gravity, 32, 115012. K., Espada, D., Kameno, S., Sawada, T., Takahashi, S., Ao, Y., Abbott, B. P., et al. including Flaminio, R., LIGO Scientific Hatsukade, B., Matsuda, Y., Iono, D., Kurono, Y.: 2015, The 2014 Collaboration, Virgo Collaboration: 2016, Astrophysical Implications ALMA Long Baseline Campaign: Observations of the Strongly of the Binary Black Hole Merger GW150914, ApJ, 818, L22. Lensed Submillimeter Galaxy HATLAS J090311.6+003906 at z = Abbott, B. P., et al. including Flaminio, R., LIGO Scientific 3.042, ApJ, 808, L4. Collaboration, Virgo Collaboration: 2016, Observation of ALMA Partnership, et al. including Asaki, Y., Hirota, A., Nakanishi, Gravitational Waves from a Binary Black Hole Merger, Phys. Rev. K., Espada, D., Kameno, S., Sawada, T., Takahashi, S., Kurono, Lett., 116, 061102. Y., Tatematsu, K.: 2015, The 2014 ALMA Long Baseline Campaign: Abbott, B. P., et al. including Flaminio, R., LIGO Scientific Observations of Asteroid 3 Juno at 60 Kilometer Resolution, ApJ, Collaboration, Virgo Collaboration: 2016, GW150914: Implications 808, L2. for the Stochastic Gravitational-Wave Background from Binary Black Alonso-Herrero, A., et al. including Imanishi, M.: 2016, A mid-infrared Holes, Phys. -
White Dwarfs
Chandra X-Ray Observatory X-Ray Astronomy Field Guide White Dwarfs White dwarfs are among the dimmest stars in the universe. Even so, they have commanded the attention of astronomers ever since the first white dwarf was observed by optical telescopes in the middle of the 19th century. One reason for this interest is that white dwarfs represent an intriguing state of matter; another reason is that most stars, including our sun, will become white dwarfs when they reach their final, burnt-out collapsed state. A star experiences an energy crisis and its core collapses when the star's basic, non-renewable energy source - hydrogen - is used up. A shell of hydrogen on the edge of the collapsed core will be compressed and heated. The nuclear fusion of the hydrogen in the shell will produce a new surge of power that will cause the outer layers of the star to expand until it has a diameter a hundred times its present value. This is called the "red giant" phase of a star's existence. A hundred million years after the red giant phase all of the star's available energy resources will be used up. The exhausted red giant will puff off its outer layer leaving behind a hot core. This hot core is called a Wolf-Rayet type star after the astronomers who first identified these objects. This star has a surface temperature of about 50,000 degrees Celsius and is A composite furiously boiling off its outer layers in a "fast" wind traveling 6 million image of the kilometers per hour. -
Observing List
day month year Epoch 2000 local clock time: 23.98 Observing List for 23 7 2019 RA DEC alt az Constellation object mag A mag B Separation description hr min deg min 20 50 Andromeda Gamma Andromedae (*266) 2.3 5.5 9.8 yellow & blue green double star 2 3.9 42 19 28 69 Andromeda Pi Andromedae 4.4 8.6 35.9 bright white & faint blue 0 36.9 33 43 30 55 Andromeda STF 79 (Struve) 6 7 7.8 bluish pair 1 0.1 44 42 16 52 Andromeda 59 Andromedae 6.5 7 16.6 neat pair, both greenish blue 2 10.9 39 2 45 67 Andromeda NGC 7662 (The Blue Snowball) planetary nebula, fairly bright & slightly elongated 23 25.9 42 32.1 31 60 Andromeda M31 (Andromeda Galaxy) large sprial arm galaxy like the Milky Way 0 42.7 41 16 31 61 Andromeda M32 satellite galaxy of Andromeda Galaxy 0 42.7 40 52 32 60 Andromeda M110 (NGC205) satellite galaxy of Andromeda Galaxy 0 40.4 41 41 17 55 Andromeda NGC752 large open cluster of 60 stars 1 57.8 37 41 17 48 Andromeda NGC891 edge on galaxy, needle-like in appearance 2 22.6 42 21 45 69 Andromeda NGC7640 elongated galaxy with mottled halo 23 22.1 40 51 46 57 Andromeda NGC7686 open cluster of 20 stars 23 30.2 49 8 30 121 Aquarius 55 Aquarii, Zeta 4.3 4.5 2.1 close, elegant pair of yellow stars 22 28.8 0 -1 12 120 Aquarius 94 Aquarii 5.3 7.3 12.7 pale rose & emerald 23 19.1 -13 28 32 152 Aquarius M72 globular cluster 20 53.5 -12 32 31 151 Aquarius M73 Y-shaped asterism of 4 stars 20 59 -12 38 16 117 Aquarius NGC7606 Galaxy 23 19.1 -8 29 32 149 Aquarius NGC7009 Saturn Neb planetary nebula, large & bright pale green oval 21 4.2 -11 21.8 38 135 -
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. -
SHELL BURNING STARS: Red Giants and Red Supergiants
SHELL BURNING STARS: Red Giants and Red Supergiants There is a large variety of stellar models which have a distinct core – envelope structure. While any main sequence star, or any white dwarf, may be well approximated with a single polytropic model, the stars with the core – envelope structure may be approximated with a composite polytrope: one for the core, another for the envelope, with a very large difference in the “K” constants between the two. This is a consequence of a very large difference in the specific entropies between the core and the envelope. The original reason for the difference is due to a jump in chemical composition. For example, the core may have no hydrogen, and mostly helium, while the envelope may be hydrogen rich. As a result, there is a nuclear burning shell at the bottom of the envelope; hydrogen burning shell in our example. The heat generated in the shell is diffusing out with radiation, and keeps the entropy very high throughout the envelope. The core – envelope structure is most pronounced when the core is degenerate, and its specific entropy near zero. It is supported against its own gravity with the non-thermal pressure of degenerate electron gas, while all stellar luminosity, and all entropy for the envelope, are provided by the shell source. A common property of stars with well developed core – envelope structure is not only a very large jump in specific entropy but also a very large difference in pressure between the center, Pc, the shell, Psh, and the photosphere, Pph. Of course, the two characteristics are closely related to each other. -
PSR J1740-3052: a Pulsar with a Massive Companion
Haverford College Haverford Scholarship Faculty Publications Physics 2001 PSR J1740-3052: a Pulsar with a Massive Companion I. H. Stairs R. N. Manchester A. G. Lyne V. M. Kaspi Fronefield Crawford Haverford College, [email protected] Follow this and additional works at: https://scholarship.haverford.edu/physics_facpubs Repository Citation "PSR J1740-3052: a Pulsar with a Massive Companion" I. H. Stairs, R. N. Manchester, A. G. Lyne, V. M. Kaspi, F. Camilo, J. F. Bell, N. D'Amico, M. Kramer, F. Crawford, D. J. Morris, A. Possenti, N. P. F. McKay, S. L. Lumsden, L. E. Tacconi-Garman, R. D. Cannon, N. C. Hambly, & P. R. Wood, Monthly Notices of the Royal Astronomical Society, 325, 979 (2001). This Journal Article is brought to you for free and open access by the Physics at Haverford Scholarship. It has been accepted for inclusion in Faculty Publications by an authorized administrator of Haverford Scholarship. For more information, please contact [email protected]. Mon. Not. R. Astron. Soc. 325, 979–988 (2001) PSR J174023052: a pulsar with a massive companion I. H. Stairs,1,2P R. N. Manchester,3 A. G. Lyne,1 V. M. Kaspi,4† F. Camilo,5 J. F. Bell,3 N. D’Amico,6,7 M. Kramer,1 F. Crawford,8‡ D. J. Morris,1 A. Possenti,6 N. P. F. McKay,1 S. L. Lumsden,9 L. E. Tacconi-Garman,10 R. D. Cannon,11 N. C. Hambly12 and P. R. Wood13 1University of Manchester, Jodrell Bank Observatory, Macclesfield, Cheshire SK11 9DL 2National Radio Astronomy Observatory, PO Box 2, Green Bank, WV 24944, USA 3Australia Telescope National Facility, CSIRO, PO Box 76, Epping, NSW 1710, Australia 4Physics Department, McGill University, 3600 University Street, Montreal, Quebec, H3A 2T8, Canada 5Columbia Astrophysics Laboratory, Columbia University, 550 W. -
Chapter 16 the Sun and Stars
Chapter 16 The Sun and Stars Stargazing is an awe-inspiring way to enjoy the night sky, but humans can learn only so much about stars from our position on Earth. The Hubble Space Telescope is a school-bus-size telescope that orbits Earth every 97 minutes at an altitude of 353 miles and a speed of about 17,500 miles per hour. The Hubble Space Telescope (HST) transmits images and data from space to computers on Earth. In fact, HST sends enough data back to Earth each week to fill 3,600 feet of books on a shelf. Scientists store the data on special disks. In January 2006, HST captured images of the Orion Nebula, a huge area where stars are being formed. HST’s detailed images revealed over 3,000 stars that were never seen before. Information from the Hubble will help scientists understand more about how stars form. In this chapter, you will learn all about the star of our solar system, the sun, and about the characteristics of other stars. 1. Why do stars shine? 2. What kinds of stars are there? 3. How are stars formed, and do any other stars have planets? 16.1 The Sun and the Stars What are stars? Where did they come from? How long do they last? During most of the star - an enormous hot ball of gas day, we see only one star, the sun, which is 150 million kilometers away. On a clear held together by gravity which night, about 6,000 stars can be seen without a telescope. -
The Detached Dust Shells of AQ Andromedae, U Antliae, and TT Cygni ,
A&A 518, L140 (2010) Astronomy DOI: 10.1051/0004-6361/201014633 & c ESO 2010 Astrophysics Herschel: the first science highlights Special feature Letter to the Editor The detached dust shells of AQ Andromedae, U Antliae, and TT Cygni, F. Kerschbaum1,D.Ladjal2, R. Ottensamer1,5,M.A.T.Groenewegen3, M. Mecina1,J.A.D.L.Blommaert2, B. Baumann1,L.Decin2,4, B. Vandenbussche2 , C. Waelkens2, T. Posch1, E. Huygen2, W. De Meester2,S.Regibo2, P. Royer 2,K.Exter2, and C. Jean2 1 University of Vienna, Department of Astronomy, Türkenschanzstraße 17, 1180 Vienna, Austria e-mail: [email protected] 2 Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium 3 Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium 4 Sterrenkundig Instituut Anton Pannekoek, University of Amsterdam, Kruislaan 403, 1098 Amsterdam, The Netherlands 5 Institute of Computer Vision and Graphics, TU Graz, Inffeldgasse 16/II, A-8010 Graz, Austria Received 31 March 2010 / Accepted 12 May 2010 ABSTRACT Detached circumstellar dust shells are detected around three carbon variables using Herschel-PACS. Two of them are already known on the basis of their thermal CO emission and two are visible as extensions in IRAS imaging data. By model fits to the new data sets, physical sizes, expansion timescales, dust temperatures, and more are deduced. A comparison with existing molecular CO material shows a high degree of correlation for TT Cyg and U Ant but a few distinct differences with other observables are also found. Key words. stars: AGB and post-AGB – stars: carbon – stars: evolution – stars: mass-loss – infrared: stars 1. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Multiwavelength Study of the Fast Rotating Supergiant High-Mass X-Ray Binary IGR J16465−4507? S
A&A 591, A87 (2016) Astronomy DOI: 10.1051/0004-6361/201628110 & c ESO 2016 Astrophysics Multiwavelength study of the fast rotating supergiant high-mass X-ray binary IGR J16465−4507? S. Chaty1; 2, A. LeReun1, I. Negueruela3; 4, A. Coleiro5, N. Castro6, S. Simón-Díaz7; 8, J. A. Zurita Heras1, P. Goldoni5, and A. Goldwurm5 1 AIM (UMR 7158 CEA/DSM-CNRS-Université Paris Diderot), Irfu/Service d’Astrophysique, Centre de Saclay, 91191 Gif-sur-Yvette Cedex, France e-mail: [email protected] 2 Institut Universitaire de France, 103 boulevard Saint-Michel, 75005 Paris, France 3 Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Escuela Politécnica Superior, Universidad de Alicante, Carretera San Vicente del Raspeig s/n, 03690 San Vicente del Raspeig, Spain 4 Santa Cruz Institute for Particle Physics, University of California Santa Cruz, 1156 High St., Santa Cruz, CA 95064, USA 5 APC (UMR 7164 CEA/DSM-CNRS-Université Paris Diderot), 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France 6 Argelander Institut für Astronomie, Auf dem Hügel 71, 53121 Bonn, Germany 7 Instituto de Astrofísica de Canarias, vía Láctea s/n, 38205 La Laguna, Santa Cruz de Tenerife, Spain 8 Departamento de Astrofísica, Facultad de Física y Matemáticas, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez, s/n, 38206 La Laguna, Santa Cruz de Tenerife, Spain Received 11 January 2016 / Accepted 4 April 2016 ABSTRACT Context. Since its launch, the X-ray and γ-ray observatory INTEGRAL satellite has revealed a new class of high-mass X-ray binaries (HMXB) displaying fast flares and hosting supergiant companion stars.