Lambda Boo Stars with Composite Spectra
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Deepsky Delights
deepsky delights Deepsky Delights glow” of the Sun. However, this night by Magda Streicher belonged to Caroline Herschel. [[email protected]] Caroline (1750–1848) although small in stature was more than just a remarkable Caroline Herschel’s woman. Her unselfishness and consist- deepsky discoveries ent assistance enabled her brother Wil- Just before midnight one evening this liam and nephew John, to give the astro- past October I walked out under an ex- nomical world a rich heritage. William ceptionally dark and transparent sky, in turn equipped her with a telescope and filled with starlight. I gazed up and was encouraged her to hunt for comets. With amazed to see a very soft, large glow great perseverance and during freezing between the constellations Aquarius and cold nights in winter she found 8 comets Pisces. This very rare sight later turned and a hand-full of deepsky objects. This out to be the Gegenschein, the “counter surely must have highlighted her lonely world. The first object I turned to was NGC 6633 in Ophui- chus, with the constellation already descending in the West. My first impression revealed a bright grouping of stars of various magni- tudes. The centre exhib- ited a few brighter stars in the shape of a semi-circle, along with a faint uneven string of stars to the east that drapes from North to South. Concluding the ob- servation was a very tight group of six stars to the west. Members of queen Cas- siopeia’s crown can be seen low on the northern hori- Caroline’s Cluster: NGC 2360 in Canis Major was dis- zon where they only bow covered in the late 18th century by Caroline Herschel. -
An Evaluation of the Membership Probability of 212$\Lambda $ Boo Stars: I. a Catalogue
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 18 July 2018 (MN LATEX style file v2.2) An evaluation of the membership probability of 212 λ Boo stars: I. A Catalogue. Simon J. Murphy1,2,†, Christopher J. Corbally3, Richard O. Gray4, Kwang-Ping Cheng5, James E. Neff6, Chris Koen7, Charles A. Kuehn1,2, Ian Newsome4 and Quinlin Riggs4 1 Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006, Australia 2 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark 3 Vatican Observatory Research Group, Steward Observatory, Tucson, AZ 85721-0065, USA 4 Department of Physics and Astronomy, Appalachian State University, Boone, NC 28608, USA 5 Department of Physics, California State University, Fullerton, CA, USA 6 Department of Physics and Astronomy, College of Charleston, Charleston, SC, USA 7 Department of Statistics, University of the Western Cape, Private Bag X17, Bellville, 7535 Cape, South Africa †email: [email protected] 18 July 2018 ABSTRACT The literature on the λ Boo stars has grown to become somewhat heterogenous, as different authors have applied different criteria across the UV, optical and infrared regions to determine the membership status of λ Boo candidates. We aim to clear up the confusion by consulting the literature on 212 objects that have been consid- ered as λ Boo candidates, and subsequently evaluating the evidence in favour of their admission to the λ Boo class. We obtained new spectra of ∼90 of these candidates and classified them on the MK system to aid in the membership evaluations. -
The Heterogeneous Class of Λ Bootis Stars?,??
A&A 412, 447–464 (2003) Astronomy DOI: 10.1051/0004-6361:20031472 & c ESO 2003 Astrophysics The heterogeneous class of λ Bootis stars?;?? M. Gerbaldi1,2, R. Faraggiana3,andO.Lai4 1 Institut d’Astrophysique, 98bis Bd. Arago, 75014 Paris, France 2 Lab. Astronomie, Bˆat. 470, Universit´e de Paris Sud XI, 91405 Orsay Cedex, France 3 Dipartimento di Astronomia, Universit`a degli Studi di Trieste, via G.B. Tiepolo 11, 34131 Trieste, Italy e-mail: [email protected] 4 Canada-France-Hawaii Telescope (CFHT) Corporation, Kamuela, HI 96743, USA e-mail: [email protected] Received 10 June 2003 / Accepted 12 September 2003 Abstract. We demonstrate that it is arduous to define the λ Boo stars as a class of objects exhibiting uniform abundance peculiarities which would be generated by a mechanism altering the structure of their atmospheric layers. We collected the stars classified as λ Boo up to now and discuss their properties, in particular the important percentage of confirmed binaries producing composite spectra (including our adaptive optics observations) and of misclassified objects. The unexplained RV variables (and thus suspected binaries), the known SB for which we lack information on the companion, the stars with an UV flux inconsistent with their classification, and the fast rotating stars for which no accurate abundance analysis can be performed, are also reviewed. Key words. stars: atmospheres – stars: chemically peculiar – stars: binaries: spectroscopic 1. Introduction Only 12 stars were classified as λ BoointheCatalog of Stellar Groups (Jaschek & Egret 1982) and 2 of them The peculiarity of the λ Boo star was detected by Morgan et al. -
The Caldwell Catalogue Contents
The Caldwell Catalogue Contents 1 Overview 1 1.1 Caldwell catalogue ........................................... 1 1.1.1 Caldwell Star Chart ...................................... 1 1.1.2 Number of objects by type in the Caldwell catalogue. .................... 1 1.1.3 Caldwell objects ....................................... 1 1.1.4 See also ............................................ 2 1.1.5 References .......................................... 2 1.1.6 External links ......................................... 2 1.2 Patrick Moore ............................................. 2 1.2.1 Early life ........................................... 2 1.2.2 Career in astronomy ...................................... 3 1.2.3 Activism and political beliefs ................................. 5 1.2.4 Other interests and popular culture .............................. 5 1.2.5 Honours and appointments .................................. 6 1.2.6 Bibliography ......................................... 7 1.2.7 Film and television appearances ................................ 7 1.2.8 See also ............................................ 7 1.2.9 References .......................................... 7 1.2.10 External links ......................................... 9 2 Objects 10 2.1 Caldwell 1 ............................................... 10 2.1.1 References .......................................... 10 2.1.2 External links ......................................... 10 2.2 Caldwell 2 ............................................... 10 2.2.1 Gallery ........................................... -
Bootis Stars with Composite Spectra
A&A 425, 615–626 (2004) Astronomy DOI: 10.1051/0004-6361:20040216 & c ESO 2004 Astrophysics λ Bootis stars with composite spectra R. Faraggiana1,P.Bonifacio2,E.Caffau2,M.Gerbaldi3,4, and M. Nonino2 1 Dipartimento di Astronomia, Università degli Studi di Trieste, via G.B. Tiepolo 11, 34131 Trieste, Italy e-mail: [email protected] 2 Istituto Nazionale per l’Astrofisica – Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, 34131 Trieste, Italy 3 Institut d’Astrophysique, 98 bis Bd. Arago, 75014 Paris, France 4 Université de Paris Sud XI, France Received 6 February 2004 / Accepted 3 June 2004 Abstract. Weexaminethelargesampleofλ Boo candidates collected in Table 1 of Gerbaldi et al. (2003) to see how many of them show composite spectra. Of the 132 λ Boo candidates we identify 22 which definitely show composite spectra and 15 more for which there are good reasons to suspect a composite spectrum. The percentage of λ Boo candidates with composite spectra is therefore >17% and possibly considerably higher. For such stars the λ Boo classification should be reconsidered taking into account the fact that their spectra are composite. We argue that some of the underabundances reported in the literature may simply be the result of the failure to consider the composite nature of the spectra. This leads to the legitimate suspicion that some, if not all, the λ Boo candidates are not chemically peculiar at all. A thorough analysis of even a single one of the λ Boo candidates with composite spectra, in which the composite nature of the spectrum is duly considered, which would demonstrate that the chemical peculiarities persist, would clear the doubt we presently have that the stars with composite spectra may not be λ Boo stars at all. -
An Evaluation of the Membership Probability of 212 Λ Boo Stars. I. a Catalogue
Publications of the Astronomical Society of Australia (PASA), Vol. 32, e036, 43 pages (2015). C Astronomical Society of Australia 2015; published by Cambridge University Press. doi:10.1017/pasa.2015.34 An Evaluation of the Membership Probability of 212 λ Boo Stars. I. A Catalogue Simon J. Murphy1,2,8, Christopher J. Corbally3, Richard O. Gray4, Kwang-Ping Cheng5, James E. Neff6, Chris Koen7, Charles A. Kuehn1,2, Ian Newsome4 and Quinlin Riggs4 1Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006, Australia 2Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark 3Vatican Observatory Research Group, Steward Observatory, Tucson, AZ 85721-0065, USA 4Department of Physics and Astronomy, Appalachian State University, Boone, NC 28608, USA 5Department of Physics, California State University, Fullerton, CA, USA 6Department of Physics and Astronomy, College of Charleston, Charleston, SC, USA 7Department of Statistics, University of the Western Cape, Private Bag X17, Bellville, 7535 Cape, South Africa 8Email: [email protected] (Received July 06, 2015; Accepted August 14, 2015) Abstract The literature on the λ Boo stars has grown to become somewhat heterogenous, as different authors have applied different criteria across the UV, optical, and infrared regions to determine the membership status of λ Boo candidates. We aim to clear up the confusion by consulting the literature on 212 objects that have been considered as λ Boo candidates, and subsequently evaluating the evidence in favour of their admission to the λ Boo class. We obtained new spectra of ∼90 of these candidates and classified them on the MK system to aid in the membership evaluations. -
Redox DAS Artist List for Period: 01.03.2018
Page: 1 Redox D.A.S. Artist List for period: 01.03.2018 - 31.03.2018 Date time: Number: Title: Artist: Publisher Lang: 01.03.2018 00:02:34 HD 54559 VALCEK FLIRRT SLO 01.03.2018 00:05:43 HD 19796 GOOD TRADITION TANITA TIKARAM ANG 01.03.2018 00:08:31 HD 60787 UNPREDICTABLE OLLY MURS & LOUISA JOHNSON ANG 01.03.2018 00:11:49 HD 60168 MY SIDE OF THE BED SUSANNA HOFFS ANG 01.03.2018 00:15:04 HD 55202 DAN KOT IZ SANJ YLENIA ZOBEC SLO 01.03.2018 00:18:04 HD 35165 RIGHT HERE IN MY ARMS HIM ANG 01.03.2018 00:22:07 HD 58663 ONE DANCE (FEAT. WIZKID & KYLA) DRAKE ANG 01.03.2018 00:24:57 HD 00874 SOLINAR FARAONI SLO 01.03.2018 00:28:26 HD 61255 TOUCH ME (FEAT. SAMANTHA FOX) SAN DI EGO ANG 01.03.2018 00:32:12 HD 60092 OOH LA LA FACES ANG 01.03.2018 00:35:28 HD 34944 VEST BOHEM SLO 01.03.2018 00:39:40 HD 29589 ALL IN THE NAME OF LOVE WILLY DEVILLE ANG 01.03.2018 00:43:18 HD 60254 KAO SEVERINA HRV 01.03.2018 00:46:53 HD 00430 JULIJA ALEKSANDER MEZEK SLO 01.03.2018 00:50:47 HD 50060 THIS OLD HOUSE BORIS GARDINER ANG 01.03.2018 00:55:15 HD 31173 HAVE YOU EVER SEEN THE RAIN ROD STEWART ANG 01.03.2018 00:58:17 HD 55444 ZRACIS MOJ ZRAK IRENA VRCKOVNIK SLO 01.03.2018 01:01:30 HD 61219 HAZARDER (FEAT.