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Wilson-Bappu Effect: Extended to Surface Gravity [email protected] Sunkyung Park1, Jeong-Eun Lee1, Wonseok Kang1, Sang-Gak Lee2 1School of Space Research, Kyung Hee University 2 Astronomy Program, Department of Physics and Astronomy, Seoul National University Wilson and Bappu found a tight correlation between the stellar absolute visual magnitude (MV) and the width of the Ca II K emission line for late-type stars in 1957. Here, we revisit the Wilson- Bappu relation (hereafter, WBR) to claim that WBR can be an excellent indicator of stellar surface gravity of late-type stars as well as a distance indicator. We have measured the width of the Ca II K emission line (log W) in high resolution spectra of 125 late-type stars, which were obtained with Bohyunsan Optical Echelle Spectrograph (BOES) and adopted from the UVES archive. Based on our measurement of the emission line width (log W), we have obtained a WBR of MV = 33.76 – 18.08 log W. In order to extend the WBR to be a surface gravity indicator, the stellar atmospheric parameters such as effective temperature (Teff), surface gravity (log g), metallicity ([Fe/H]), and micro-turbulence (ξtur) have been derived from the self-consistent detailed analysis using the Kurucz stellar atmospheric model and the abundance analysis code, MOOG. Using these stellar parameters and log W, we found that log g = - 5.85 log W + 9.97 log Teff - 23.48 for late-type stars. Accepted by AJ. arXiv:1307.0592 ★ Wilson – Bappu Relation (WBR) : Wilson and Bappu (1957) found a strong relationship between the absolute visual magnitude (MV) and the width of the Ca II K emission line (log W) ★ Application of WBR to the Distance Table 1. -
Astronomy Astrophysics
A&A 406, 995–999 (2003) Astronomy DOI: 10.1051/0004-6361:20030647 & c ESO 2003 Astrophysics High resolution spectroscopy over λλ 8500 8750 Å for GAIA? − IV. Extending the cool MK stars sample P. M. Marrese1;2, F. Boschi1, and U. Munari1 1 Padova Astronomical Observatory - INAF, Asiago Station, Via Osservatorio 8, 36012 Asiago (VI), Italy e-mail: [email protected], [email protected] 2 Department of Astronomy, University of Padova, Vicolo Osservatorio 8, 35122 Padova, Italy Received 12 December 2002 / Accepted 24 April 2003 Abstract. A library of high resolution spectra of MK standard and reference stars, observed in support to the GAIA mission, is presented. The aim of this paper is to integrate the MK mapping of Paper I of this series as well as to consider stars over a wider range of metallicities. Radial velocities are measured for all the target stars. Key words. atlases – standards – stars: fundamental parameters 1. Introduction 2 and 3 give examples of the collected spectra and illustrate respectively the effect of gravity and metallicity at G5 (com- This paper is the fourth of a series devoted to the spectroscopy pare with Fig. 2 in Paper I), the effect of gravity at F5 and at of the ESA Cornerstone mission GAIA. The GAIA Radial K4. Velocity Spectrometer (RVS) will provide the 6th component of the phase-space coordinates for all stars brighter than V = 2. Target selection 17:5 magnitude. High resolution (R 20 000) high signal to Table 1 lists the target stars, ordered by spectral type, and noise (S=N 100) spectra of cool (later∼ than F0) MK stan- Table 2 the references to it. -
8500-8750 Ε for GAIA
A&A 406, 995–999 (2003) Astronomy DOI: 10.1051/0004-6361:20030647 & c ESO 2003 Astrophysics High resolution spectroscopy over λλ 8500 8750 Å for GAIA? − IV. Extending the cool MK stars sample P. M. Marrese1;2, F. Boschi1, and U. Munari1 1 Padova Astronomical Observatory - INAF, Asiago Station, Via Osservatorio 8, 36012 Asiago (VI), Italy e-mail: [email protected], [email protected] 2 Department of Astronomy, University of Padova, Vicolo Osservatorio 8, 35122 Padova, Italy Received 12 December 2002 / Accepted 24 April 2003 Abstract. A library of high resolution spectra of MK standard and reference stars, observed in support to the GAIA mission, is presented. The aim of this paper is to integrate the MK mapping of Paper I of this series as well as to consider stars over a wider range of metallicities. Radial velocities are measured for all the target stars. Key words. atlases – standards – stars: fundamental parameters 1. Introduction 2 and 3 give examples of the collected spectra and illustrate respectively the effect of gravity and metallicity at G5 (com- This paper is the fourth of a series devoted to the spectroscopy pare with Fig. 2 in Paper I), the effect of gravity at F5 and at of the ESA Cornerstone mission GAIA. The GAIA Radial K4. Velocity Spectrometer (RVS) will provide the 6th component of the phase-space coordinates for all stars brighter than V = 2. Target selection 17:5 magnitude. High resolution (R 20 000) high signal to Table 1 lists the target stars, ordered by spectral type, and noise (S=N 100) spectra of cool (later∼ than F0) MK stan- Table 2 the references to it. -
The Pre-Main-Sequence Star IP Persei
A&A 377, 854–867 (2001) Astronomy DOI: 10.1051/0004-6361:20010958 & c ESO 2001 Astrophysics The pre-main-sequence star IP Persei A. S. Miroshnichenko1,2,K.S.Bjorkman1,E.L.Chentsov3,4,V.G.Klochkova3,4,R.O.Gray5, P. Garc´ıa-Lario6, and J. V. Perea Calder´on7 1 Ritter Observatory, Dept. of Physics & Astronomy, University of Toledo, Toledo, OH 43606-3390, USA 2 Central Astronomical Observatory of the Russian Academy of Sciences at Pulkovo, 196140, Saint-Petersburg, Russia 3 Special Astrophysical Observatory of the Russian Academy of Sciences, Karachai-Cirkassian Republic, Nizhnij Arkhyz, 369167, Russia 4 Issac Newton Institute of Chile, SAO Branch, Russia 5 Dept. of Physics and Astronomy, Appalachian State University, Boone, NC 28608, USA 6 ISO Data Centre, Astrophysics Division, Space Science Department of ESA, Villafranca del Castillo, Apartado de Correos 50727, 28080 Madrid, Spain 7 INSA SA, Villafranca del Castillo, Apartado de Correos 50727, 28080 Madrid, Spain Received 19 March 2001 / Accepted 21 June 2001 Abstract. We present the results of high- and low-resolution spectroscopic and broadband multicolour photometric observations of the emission-line A-type star IP Per. Significant variations of the Balmer line profiles and near-IR brightness are detected. Comparison with the spectra of other stars and theoretical models allowed us to derive its fundamental parameters as follows: Teff ' 8000 K, log g ' 4.4, log Lbol/L ' 1.0. They correspond to the MK type A7 v. We also found that the metallicity of the object’s atmosphere is nearly 40 per cent that of the Sun. -
The Atmospheric Parameters and Spectral Interpolator for the MILES Stars
A&A 531, A165 (2011) Astronomy DOI: 10.1051/0004-6361/201116769 & c ESO 2011 Astrophysics The atmospheric parameters and spectral interpolator for the MILES stars Ph. Prugniel1, I. Vauglin1,andM.Koleva2,1 1 Université de Lyon, Université Lyon 1, 69622 Villeurbanne, France; CRAL, Observatoire de Lyon, CNRS UMR 5574, 69561 Saint-Genis Laval, France e-mail: [philippe.prugniel;isabelle.vauglin]@univ-lyon1.fr 2 Instituto de Astrofísica de Canarias, La Laguna, 38200 Tenerife, Spain; Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain e-mail: [email protected] Received 22 February 2011 / Accepted 16 April 2011 ABSTRACT Context. Empirical libraries of stellar spectra are used to classify stars and synthetize stellar populations. MILES is a medium spectral- resolution library in the optical domain covering a wide range of temperatures, surface gravities and metallicities. Aims. We redetermine the atmospheric parameters of these stars in order to improve the homogeneity and accuracy. We build an interpolating function that returns a spectrum as a function of the three atmospheric parameters, and finally we characterize the precision of the wavelength calibration and stability of the spectral resolution. Methods. We used the ULySS program with the ELODIE library as a reference and compared the results with those in the literature. Results. We obtain precisions of 60 K, 0.13, and 0.05 dex, respectively, for Teff ,logg,and[Fe/H] for the FGK stars. For the M stars, the mean errors are 38 K, 0.26, and 0.12 dex and 3.5%, 0.17, and 0.13 dex for the OBA. -
The Electric Sun Hypothesis
Basics of astrophysics revisited. II. Mass- luminosity- rotation relation for F, A, B, O and WR class stars Edgars Alksnis [email protected] Small volume statistics show, that luminosity of bright stars is proportional to their angular momentums of rotation when certain relation between stellar mass and stellar rotation speed is reached. Cause should be outside of standard stellar model. Concept allows strengthen hypotheses of 1) fast rotation of Wolf-Rayet stars and 2) low mass central black hole of the Milky Way. Keywords: mass-luminosity relation, stellar rotation, Wolf-Rayet stars, stellar angular momentum, Sagittarius A* mass, Sagittarius A* luminosity. In previous work (Alksnis, 2017) we have shown, that in slow rotating stars stellar luminosity is proportional to spin angular momentum of the star. This allows us to see, that there in fact are no stars outside of “main sequence” within stellar classes G, K and M. METHOD We have analyzed possible connection between stellar luminosity and stellar angular momentum in samples of most known F, A, B, O and WR class stars (tables 1-5). Stellar equatorial rotation speed (vsini) was used as main parameter of stellar rotation when possible. Several diverse data for one star were averaged. Zero stellar rotation speed was considered as an error and corresponding star has been not included in sample. RESULTS 2 F class star Relative Relative Luminosity, Relative M*R *eq mass, M radius, L rotation, L R eq HATP-6 1.29 1.46 3.55 2.950 2.28 α UMi B 1.39 1.38 3.90 38.573 26.18 Alpha Fornacis 1.33 -
Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April
Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April An Atlas of Southern MK Standards From 5800 to 10,200 A1 Anthony C. Danks Hughes STX/Goddard Space Flight Center, Code 683.0, Greenbelt, Maryland 20771 Michel Dennefeld Institut d'Astrophysique, 98bis Boulevard Arago, F-75014 Paris, France Received 1992 December 30; accepted 1994 February 2 ABSTRACT. An atlas of stellar spectra covering the wavelength range from 5800 to 10,200 A is presented of 126 southern MK standard stars, covering the luminosity classes I, III, and V. Some peculiar stars are included for comparison purposes. The spectra were obtained at a resolution of 4.3 A per pixel using a Cassegrain-mounted Boiler and Chivens spectrograph equipped with a Reticon detector. The quality and utility of the data are discussed and examples of the spectra are presented. The atlas is available in digital format through the NSSDC. 1. INTRODUCTION tion of 15 A which is lower than that used in this atlas, but overlaps nicely in wavelength. Mantegazza (1992) has be- Spectral synthesis of galaxies is one of the major driving forces for producing new stellar libraries covering as large gun the work of extending calibration to the Magellanic a spectral interval as possible. The "photographic" wave- clouds by observing 34 LMC and 15 SMC supergiants be- length region from 3800 to 4800 A, initially used for the tween AO and G5 in the wavelength range from 5600 to MK classification scheme, has been extended to shorter 9000 A, interestingly made with the same spectrograph as wavelengths through space technology. -
Redox DAS Artist List for Period: 01.08.2017
Page: 1 Redox D.A.S. Artist List for period: 01.08.2017 - 31.08.2017 Date time: Number: Title: Artist: Publisher Lang: 01.08.2017 00:02:09 HD 04463 BOBBY BROWN FRANK ZAPPA ANG 01.08.2017 00:04:55 HD 55594 LJUBEZEN HLADNEGA DEKLETA THE STICKY LICKS SLO 01.08.2017 00:09:59 HD 46532 PARTY ALL NIGHT (SLEEP ALL DAY) [ALBUMSEAN KINGSTON VERSION] ANG 01.08.2017 00:13:47 HD 40707 FLAME TREES COLD CHISEL ANG 01.08.2017 00:18:07 HD 52793 TUDI TI A-NI-TA SLO 01.08.2017 00:21:11 HD 42017 UNANSWERED PRAYERS GARTH BROOKS ANG 01.08.2017 00:24:43 HD 34818 LIFTED LIGHTHOUSE FAMILY ANG 01.08.2017 00:28:48 HD 10759 EMANUELLE MAGNIFICO SLO 01.08.2017 00:33:33 HD 16344 DO SOMETHIN' BRITNEY SPEARS ANG 01.08.2017 00:37:01 HD 36333 PUMPKIN SOUP KATE NASH ANG 01.08.2017 00:40:00 HD 52816 V RITMU SANJ KATRINAS SLO 01.08.2017 00:44:06 HD 36201 MILLION FACES PAOLO NUTINI ANG 01.08.2017 00:47:44 HD 58724 BREATHE (FEAT NEEV) SEEB ANG 01.08.2017 00:51:30 HD 12353 PRID K MEN PETER LOVSIN & VITEZI OM'A SLO 01.08.2017 00:55:11 HD 10793 EVERY BREATH YOU TAKE FAME ACADEMY ANG 01.08.2017 00:59:03 HD 42719 UNTIL I DIE SEPTEMBER ANG 01.08.2017 01:02:43 HD 44564 BREZ OBRAZA REBEKA & TRKAJ SLO 01.08.2017 01:05:54 HD 25447 QUANDO, QUANDO, QUANDO MICHAEL BUBLE FT NELLY FURTADO ANG 01.08.2017 01:10:43 HD 54865 GIVING ME AWAY BETTY WHO ANG 01.08.2017 01:14:39 HD 21353 HELENA FOLKROLA SLO 01.08.2017 01:17:57 HD 02753 DANCE (WITH YOU) LEMAR ANG 01.08.2017 01:21:27 HD 56725 DON'T WE BELONG IN LOVE STEPHANIE WINSLOW ANG 01.08.2017 01:23:43 HD 42913 HALO DAN D SLO 01.08.2017 01:27:10 HD 52736 THE WORLD IS YOURS JUSTIN'S CASE ANG 01.08.2017 01:30:59 HD 27349 LIVE YOUR LIFE BE FREE BELINDA CARLISLE ANG 01.08.2017 01:35:11 HD 50937 TINA MANCA SPIK SLO 01.08.2017 01:38:11 HD 43429 BELLE OF THE BOULEVARD DASHBOARD CONFESSIONAL ANG 01.08.2017 01:41:38 HD 13655 OBVIOUS WESTLIFE ANG 01.08.2017 01:45:02 HD 52083 SLADOLED NE ME JUGAT SLO 01.08.2017 01:48:29 HD 53183 BROTHER LOUIE MIX '98 MODERN TALKING FEAT. -
Population Synthesis in the Blue IV: Accurate Model Predictions for Lick
To Appear in The Astrophysical Journal Supplement Series A Preprint typeset using LTEX style emulateapj v. 08/22/09 POPULATION SYNTHESIS IN THE BLUE IV. ACCURATE MODEL PREDICTIONS FOR LICK INDICES AND UBV COLORS IN SINGLE STELLAR POPULATIONS Ricardo P. Schiavon1 Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 To Appear in The Astrophysical Journal Supplement Series ABSTRACT We present a new set of model predictions for 16 Lick absorption line indices from Hδ through Fe5335, and UBV colors for single stellar populations with ages ranging between 1 and 15 Gyr, and [Fe/H] ranging from –1.3 to +0.3, and variable abundance ratios. The models are based on accurate stellar parameters for the Jones library stars and a new set of fitting functions describing the behavior of line indices as a function of effective temperature, surface gravity, and iron abundance. The abundances of several key elements in the library stars have been obtained from the literature in order to characterize the abundance pattern of the stellar library, thus allowing us to produce model predictions for any set of abundance ratios desired. We develop a method to estimate mean ages and abundances of iron, carbon, nitrogen, magnesium and calcium that explores the sensitivity of the various indices modeled to those parameters. The models are compared to high S/N data for Galactic clusters spanning the range of ages, metallicities and abundance pattern of interest. Essentially all line indices are matched when the known cluster parameters are adopted as input. Cluster spectroscopic ages determined from different Balmer line indices are consistent to within ∼ 1 Gyr. -
Mg and Tio Spectral Features at the Near-IR: Spectrophotometric Index
Mon. Not. R. Astron. Soc. 000, 1–?? (2000) Printed 25 September 2018 (MN LaTEX style file v1.4) Mg and TiO spectral features at the near-IR: Spectrophotometric index definitions and empirical calibrations ⋆ A.J. Cenarro1, N. Cardiel2, A. Vazdekis1, and J. Gorgas2 1Instituto de Astrof´ısica de Canarias, E-38200, La Laguna, Tenerife, Spain. 2Depto. de Astrof´ısica, Fac. de Ciencias F´ısicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Accepted 2009 March 26. Received 2008 December 4 ABSTRACT Using the near-infrared spectral stellar library of Cenarro et al. (2001a,b), the behaviours of the Mg i line at 8807 A˚ and nearby TiO bands are analyzed in terms of the effective temperature, surface gravity, and metallicity of the library stars. New spectroscopic indices for both spectral features —namely MgI and sTiO— are defined, and their sensitivities to different signal-to-noise ratios, spectral resolutions, flux cali- brations, and sky emission line residuals are characterized. The new two indices exhibit interesting properties. In particular, MgI reveals as a good indicator of the Mg abun- dance, whereas sTiO is a powerful dwarf-to-giant discriminator for cold spectral types. Empirical fitting polynomials that reproduce the strength of the new indices as a func- tion of the stellar atmospheric parameters are computed, and a fortran routine with the fitting functions predictions is made available. A thorough study of several error sources, non-solar [Mg/Fe] ratios, and their influence on the fitting function residuals is also presented. From this analysis, a [Mg/Fe] underabundance of ∼−0.04 is derived for the Galactic open cluster M67. -
HD 19993 and HD 29035: New Bright A-Type Emission-Line Stars
HD 19993 and HD 29035: New bright A-type emission-line stars By: A. S. Miroshnichenko, A. V. Kusakin, K. S. Bjorkman, N. A. Drake, R. J. Rudy, D. K. Lynch, S. Mazuk, C. C. Venturini, R. C. Puetter, and R. B. Perry Miroshnichenko, A.S., Kusakin, A.V., Bjorkman, K.S., Drake, N.A., Rudy, R.J., Lynch, D.K., Mazuk, S., Venturini, C.C., Puetter, R.C., Perry, R.B. 2003. A&A, 412, 219-228. HD 19993 and HD 29035: new bright A-type emission-line stars. Made available courtesy of EDP Sciences: http://publications.edpsciences.org/ *** Note: Figures may be missing from this format of the document Abstract: We present the results of photometric and spectroscopic observations of two A-type stars (HD 19993 and HD 29035), optical counterparts of the IRAS sources (F03108+3729 and 04331+5211, respectively). Hα line emission is found in the optical spectra of both objects for the first time. Our analysis of the spectral line profiles and the photometric information shows that HD 19993 is an A7/8 II star (Teff ~ 7500 ± 200 K, log g −1 = 2.7 ± 0.2, v sin i = 35 ± 2 km s , M = 4.8 ± 0.8 M⨀) with a mild metal deficit ([Fe/H] ~ −0.3 ± 0.1), while −1 HD 29035 is a B9/A0 V star (Teff ~ 10 000 K, log g ~ 4, v sin i ~ 150 km s ). The presence of an IR excess and the Hα emission in combination with a very different location in the Hertzsprung-Russell diagram suggest the different nature and evolutionary stages of the objects. -
ASTRONOMY and ASTROPHYSICS Understanding A-Type Supergiants II
Astron. Astrophys. 346, 819–830 (1999) ASTRONOMY AND ASTROPHYSICS Understanding A-type supergiants II. Atmospheric parameters and rotational velocities of Galactic A-type supergiants? E. Verdugo1, A. Talavera2, and A.I. Gomez´ de Castro3 1 ISO Data Centre, P.O. Box 50727, E-28080 Madrid, Spain ([email protected]) 2 LAEFF/INTA, P.O. Box 50727, E-28080 Madrid, Spain ([email protected]) 3 Instituto de Astronom´ıa y Geodesia (CSIC-UCM), Fac. cc. Matematicas,´ Universidad Complutense, Av. Complutense s/n, E-28040 Madrid, Spain ([email protected]) Received 14 October 1997 / Accepted 12 April 1999 Abstract. We present the second paper of a series whose aim is and can be observed individually in nearby galaxies from large to perform a global study of Galactic A-supergiants. Very little ground based telescopes (Humphreys 1979, 1980; Humphreys work has been carried out to determine the stellar parameters & Sandage 1980; Humphreys et al. 1990; Humphreys et al. of these stars. This is illustrated with a brief review of some 1991; Herrero et al. 1994; McCarthy et al. 1995, 1997). This previous works. In this paper we analyze the determination of opens up great possibilities for extragalactic studies if we are absolute magnitudes, spectral types and atmospheric parameters able to understand them. Such studies have to begin with galactic using the most recent Kurucz LTEblanketed model atmospheres stars, as these are bright enough to be studied in detail. Moreover and we discuss the applicability of the calibrations, such as the they are the evolutionary link between the blue and red super- Schmidt-Kaler’s (1982) calibration.