WHAT DO RADIAL VELOCITY MEASUREMENTS TELL ABOUT RV TAURI STARS?

Size: px
Start display at page:

Download "WHAT DO RADIAL VELOCITY MEASUREMENTS TELL ABOUT RV TAURI STARS?"

Transcription

1 Dig Sites of Stellar Archeology: Giant Stars in the Milky Way Ege Uni. J. of Faculty of Sci., Special Issue, 2014, WHAT DO RADIAL VELOCITY MEASUREMENTS TELL ABOUT RV TAURI STARS? Timur Şahin 1*, David L. Lambert 2, Oktay Solakcı 3 1 Department of Space Sciences and Technologies, Akdeniz University, 07058, Antalya, Türkiye 2 W. J. McDonald Observatory, The University of Texas, Austin, Texas, USA 3 Deparment of Physics, Akdeniz University, 07058, Antalya, Türkiye Abstract: In this study, we observed some selected RV Tauri stars spectroscopically for radial velocity monitoring. The high-resolution (R min ~55.000) spectra were obtained with the 2.1m Otto Struve telescope of McDonald Observatory to make abundance analysis of these stars possible. Ultimately the spectroscopic data obtained for these stars will not only be used for radial velocity measurements but also for abundance analysis hence for metallicity update in order to explain nature of observed anomalies in these stars. Here, we give a brief description of the project and present some preliminary results. Keywords: Stars: Post-AGB stars 1. INTRODUCTION RV Tauri stars are yellow super-giant stars located along the instability strip in the Hertzsprung-Russell (H-R) diagram and are characterized by shallow and deep minima with periods ranging from 20 to 150 days. When compared to AGB stars, they are seen to be located in the higher temperature region of the H-R diagram with different chemical characteristics compared to the stars on the AGB stage where nuclear reactions and (3 rd ) dredge-up processes take place. Some RV Tauri stars show anomalies in abundances of the refractory elements (e.g. Fe, Mg, Si, Al, Ti, Ca); this has been called a Gas-Dust Winnowing Effect. In the process of gas and dust winnowing, the refractory elements condensed onto dust grains and are removed from the system by the radiation pressure. Such observed depletion in the abundances of refractory elements is a common property of RV Tauri stars, however, it is not a universal property. The details for the separation of * Corresponding Author: Tel: Fax: timursahin@akdeniz.edu.tr 113

2 refractory elements in these stars are well explained and accepted in the literature. This separation process may have a little effect on some of these stars. There are also situations where this effect could be misidentified and taken into account as if it is caused by nuclear reactions. In the literature, there is no unique model to explain observed abundance anomalies in these stars. Furthermore, some RV Tauri stars show a perfect correlation between their observed abundance anomalies caused by gas and dust separation and predicted condensation temperatures. For some of these stars, the correlation is seen to be very weak. (we can think of a situation where Ca and Al abundances are too low but without significant depletion in abundances of S and Zn). For the stars in this second group, there seems to be a relation between abundance anomaly and first ionization potentials of the elements. In fact, such a relation is observed in the Solar Corona and is known as FIP (First Ionization Potential) effect. Our hypothesis is that a relation with condensation temperatures indicates a star in a binary system while a relation based on FIP would indicate a single star that experiences strong stellar winds [2]. In other words, the FIP effect should be dominant in a single star case. Such a clear definition will, of course, only be possible with a detailed spectroscopic abundance analysis of several post-agb stars. Continuous and long-term radial velocity monitoring is another important and powerful tool to use to reveal possible binary nature of an RV Tauri star. Distinguishing orbital and pulsational characteristics of such stars remains to be a difficult step that one has to take. Thus, in this context, we performed a (relatively) long-term radial velocity monitoring for 49 RV Tauri-like (i.e. RV Tau, W Vir, RR Lyr, SR type, post-agbs) IRAS stars. Our intent is to provide new velocity measurements with a typical accuracy of <0.5 km s 1 at the current epoch for selected IRAS stars. Here, we present preliminary results on the radial velocity monitoring of RV Tauri stars. We also provide information on a dedicated website specially compiled for the program stars. The website includes details on our RadVELAS code to compute heliocentric radial velocities ([3]) and wavelength calibrations, model parameters based on color-temperature calibrations to initiate 114

3 spectroscopic analysis, a snap shot view of the stellar spectrum of interest as well as the radial velocities reported in the literature for the program star (Figs. 1, 2, and 3). Figure 1. View of a top-level message on the RadVELAS website. Figure 2. Example view the website summary of AU Peg observations. 115

4 2. OBSERVATIONS High-resolution spectroscopic observations of 49 RV Tauri type stars of the Northern sky listed in Table 1 were conducted in the period from 2008 to We made use of the 2.1 m Struve reflector telescope with the CCD-equipped Sandiford Cassegrain echelle spectrograph ([1]) at the W. J. McDonald Observatory. A typical spectrum has a spectral resolving power of about 55,000. Th-Ar comparison spectra were taken right before and after every program star observation. The quality of the data was monitored by using observations of the day sky and observing one or two RV-standard stars (from the Astronomical Almanac) per night. The adopted set up of the spectrograph enabled us to cover the Å spectral range. The signalto-noise ratio (S/N) ranges between 30 and 250 per pixel, not only changing with the blaze function within echelle orders but also star brightness between echelle orders. Figure 3. Example view of the website temperatures and example spectrum. 116

5 3. DATA REDUCTION AND RADIAL VELOCITIES The observed (raw) spectra were reduced from two-dimensional to echelle format in a standard way with the ECHELLE package of NOAO IRAF1 using IRAF-CL scripts andin-house developed IDL routines. The reduction of science frames consisted of the standard steps of bias correction, cosmic-ray removal, flat fielding, scattered light subtraction, wavelength calibration, continuum normalization (see Fig. 2) and correction for the heliocentric velocity. The internal accuracy of the wavelength calibration via the Th-Ar lamp spectra was on average Å (and not worse than Å), which corresponds to an RV accuracy of order 109 m s 1 (and not worse than 218 ms 1 ). The blaze correction was performed in an automated manner using in-house IDL package RadVELAS, which is mainly designed to obtain spectroscopic radial velocities from echelle and/or long-slit spectra of RV Tauri type post-agb stars. Several processes including continuum normalization and merging are performed in an automated manner, without need for a user interaction. A continuum-normalized spectrum is cross-correlated with a mask that can be an either a stellar spectrum or a synthetic spectrum, which is degraded to the resolution of input stellar spectrum. Coefficients for fitted polynomials and peak value of crosscorrelation function are reported in a separate log file. Merged output spectra are also recorded as an SP2 file allowing one to further process the result spectrum in IDL (see [3] for details). Special care was taken during concatenation of spectral orders to a single spectrum. 4. PRELIMINARY RESULTS For this radial velocity monitoring project, all available radial velocity data in the literature for the program stars are compiled and merged with fresh radial velocities obtained with RadVELAS at the current epoch mainly to distinguish orbital and pulsational characteristics of the program stars. Here, in this section, we present IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. 117

6 example radial velocity curves for selected program stars: TX Del (Fig 4), IX Cas (Fig 5), and CP Cep (Fig 6). A summary of the orbital parameters are also presented (Table 1, 2, and 3). Radial velocities for the whole sample await publication. The dedicated webpage is not public yet but will be available soon. Figure 4. Example radial velocity curve for TX Del (W Vir type). Eccentricity: Semi-Amplitude: km/s Systemic Velocity: km/s Orbital Period: days Pulsational Period: 6 days Table 1. Summary of orbital parameters for TX Del. Figure 5. Example radial velocity curve for IX Cas (W Vir type). 118

7 Eccentricity: Semi-Amplitude: km/s Systemic Velocity: km/s Orbital Period: days Pulsational Period: 9 days Table 2. Summary of orbital parameters for IX Cas. Figure 6. Example radial velocity curve for CP Cep (δ Cep type). Eccentricity: Semi-Amplitude: km/s Systemic Velocity: km/s Orbital Period: days Pulsational Period: 9 days Table 3. Summary of orbital parameters for CP Cep. 119

8 ACKNOWLEDGMENT TS acknowledge the financial support by TUBITAK (TÜBİTAK TBAG- 1001; Project No: 111T219). Thanks to Dr. Ahmet DERVIS for his help in obtaining orbital parameters. REFERENCES [1] J. K. McCarthy, B. A. Sandiford, D. Boyd, and J. Booth, "The Sandiford 2.1-m Cassegrain echelle spectrograph for McDonald Observatory - Optical and mechanical design and performance", Publ. Astron. Soc. Pac., vol 105, pp , [2] N. K. Rao and B. E. Reddy, E. B., "High-resolution spectroscopy of the high galactic latitude RV Tauri star CE Virginis,", Mon. Not. Roy. Astron. Soc., vol. 357, pp , [3] T. Şahin, Radial Velocity Analysis Software RadVELAS," XVIII. National Astronomy and Space Sciences Meeting, İnönü Üniv., Malatya, Inonu University Publications,

CHEMICAL ABUNDANCE ANALYSIS OF RC CANDIDATE STAR HD (46 LMi) : PRELIMINARY RESULTS

CHEMICAL ABUNDANCE ANALYSIS OF RC CANDIDATE STAR HD (46 LMi) : PRELIMINARY RESULTS Dig Sites of Stellar Archeology: Giant Stars in the Milky Way Ege Uni. J. of Faculty of Sci., Special Issue, 2014, 145-150 CHEMICAL ABUNDANCE ANALYSIS OF RC CANDIDATE STAR HD 94264 (46 LMi) : PRELIMINARY

More information

Measuring Radial Velocities of Low Mass Eclipsing Binaries

Measuring Radial Velocities of Low Mass Eclipsing Binaries Measuring Radial Velocities of Low Mass Eclipsing Binaries Rebecca Rattray, Leslie Hebb, Keivan G. Stassun College of Arts and Science, Vanderbilt University Due to the complex nature of the spectra of

More information

Indirect Methods: gravitational perturbation of the stellar motion. Exoplanets Doppler method

Indirect Methods: gravitational perturbation of the stellar motion. Exoplanets Doppler method Indirect Methods: gravitational perturbation of the stellar motion Exoplanets The reflex motion of the star is proportional to M p /M * This introduces an observational bias that favours the detection

More information

Reduction procedure of long-slit optical spectra. Astrophysical observatory of Asiago

Reduction procedure of long-slit optical spectra. Astrophysical observatory of Asiago Reduction procedure of long-slit optical spectra Astrophysical observatory of Asiago Spectrograph: slit + dispersion grating + detector (CCD) It produces two-dimension data: Spatial direction (x) along

More information

THE OBSERVATION AND ANALYSIS OF STELLAR PHOTOSPHERES

THE OBSERVATION AND ANALYSIS OF STELLAR PHOTOSPHERES THE OBSERVATION AND ANALYSIS OF STELLAR PHOTOSPHERES DAVID F. GRAY University of Western Ontario, London, Ontario, Canada CAMBRIDGE UNIVERSITY PRESS Contents Preface to the first edition Preface to the

More information

International Olympiad on Astronomy and Astrophysics (IOAA)

International Olympiad on Astronomy and Astrophysics (IOAA) Syllabus of International Olympiad on Astronomy and Astrophysics (IOAA) General Notes 1. Extensive contents in basic astronomical concepts are required in theoretical and practical problems. 2. Basic concepts

More information

Midterm Observing Project: RR Lyrae, Rapidly Pulsating Stars

Midterm Observing Project: RR Lyrae, Rapidly Pulsating Stars AY 145: Topics in Astrophysics Spring, 2005 Midterm Observing Project: RR Lyrae, Rapidly Pulsating Stars Observations: March 21-24, 2005 Lab Report Due: Friday April 15, 2005 Purpose: In place of a midterm

More information

The Composition of the Old, Metal-Rich Open Cluster, NGC 6791

The Composition of the Old, Metal-Rich Open Cluster, NGC 6791 The Composition of the Old, Metal-Rich Open Cluster, NGC 6791 Liz Jensen --- Smith College, REU at IFA, University of Hawaii 2006 Mentor: Ann M. Boesgaard --- Institute for Astronomy, University of Hawaii

More information

Introduction of near-infrared (NIR) spectroscopy. Ken-ichi Tadaki (NAOJ)

Introduction of near-infrared (NIR) spectroscopy. Ken-ichi Tadaki (NAOJ) Introduction of near-infrared (NIR) spectroscopy Ken-ichi Tadaki (NAOJ) Near-infrared in astronomy absorption by terrestrial atmosphere - wavelength range of 1-5 um - observable windows are limited (J,

More information

Exploring Data. Keck LRIS spectra. Handbook of CCD Astronomy by Steve Howell Chap. 4, parts of 6

Exploring Data. Keck LRIS spectra. Handbook of CCD Astronomy by Steve Howell Chap. 4, parts of 6 Exploring Data Keck LRIS spectra Handbook of CCD Astronomy by Steve Howell Chap. 4, parts of 6 FITS: Flexible Image Transport System Digital file format used to store astronomical images, data, and catalogs.

More information

Photometric and spectroscopic observations of the outburst of the symbiotic star AG Draconis between March and June 2016

Photometric and spectroscopic observations of the outburst of the symbiotic star AG Draconis between March and June 2016 Photometric and spectroscopic observations of the outburst of the symbiotic star AG Draconis between March and June 2016 David Boyd Variable Star Section, British Astronomical Association, [davidboyd@orion.me.uk]

More information

Lab 4 Radial Velocity Determination of Membership in Open Clusters

Lab 4 Radial Velocity Determination of Membership in Open Clusters Lab 4 Radial Velocity Determination of Membership in Open Clusters Sean Lockwood 1, Dipesh Bhattarai 2, Neil Lender 3 December 2, 2007 Abstract We used the Doppler velocity of 29 stars in the open clusters

More information

Introduction The Role of Astronomy p. 3 Astronomical Objects of Research p. 4 The Scale of the Universe p. 7 Spherical Astronomy Spherical

Introduction The Role of Astronomy p. 3 Astronomical Objects of Research p. 4 The Scale of the Universe p. 7 Spherical Astronomy Spherical Introduction The Role of Astronomy p. 3 Astronomical Objects of Research p. 4 The Scale of the Universe p. 7 Spherical Astronomy Spherical Trigonometry p. 9 The Earth p. 12 The Celestial Sphere p. 14 The

More information

Spectroscopy in Astronomy

Spectroscopy in Astronomy Spectroscopy in Astronomy History 1814 German optician Joseph von Fraunhofer sun with 600+ spectral lines; now we know more than 3000 lines 1860 German chemists Gustav Kirchhoff and Robert W. Bunsen Chemical

More information

Tests of MATISSE on large spectral datasets from the ESO Archive

Tests of MATISSE on large spectral datasets from the ESO Archive Tests of MATISSE on large spectral datasets from the ESO Archive Preparing MATISSE for the ESA Gaia Mission C.C. Worley, P. de Laverny, A. Recio-Blanco, V. Hill, Y. Vernisse, C. Ordenovic and A. Bijaoui

More information

Investigating the Efficiency of the Beijing Faint Object Spectrograph and Camera (BFOSC) of the Xinglong 2.16-m Reflector

Investigating the Efficiency of the Beijing Faint Object Spectrograph and Camera (BFOSC) of the Xinglong 2.16-m Reflector Research in Astron. Astrophys. Vol. (xx) No., http://www.raa-journal.org http://www.iop.org/journals/raa Research in Astronomy and Astrophysics Investigating the Efficiency of the Beijing Faint Object

More information

Measuring the Redshift of M104 The Sombrero Galaxy

Measuring the Redshift of M104 The Sombrero Galaxy Measuring the Redshift of M104 The Sombrero Galaxy Robert R. MacGregor 1 Rice University Written for Astronomy Laboratory 230 Department of Physics and Astronomy, Rice University May 3, 2004 2 Abstract

More information

Chapter 9. Stars. The Hertzsprung-Russell Diagram. Topics for Today s Class. Phys1411 Introductory Astronomy Instructor: Dr.

Chapter 9. Stars. The Hertzsprung-Russell Diagram. Topics for Today s Class. Phys1411 Introductory Astronomy Instructor: Dr. Foundations of Astronomy 13e Seeds Phys1411 Introductory Astronomy Instructor: Dr. Goderya Chapter 9 Stars Cengage Learning 2016 Topics for Today s Class HR Diagram Variable Stars Intrinsic Variables Cepheids

More information

LI ABUNDANCES IN PTPS RED CLUMP GIANTS

LI ABUNDANCES IN PTPS RED CLUMP GIANTS Dig Sites of Stellar Archeology: Giant Stars in the Milky Way Ege Uni. J. of Faculty of Sci., Special Issue, 2014, 19-24 LI ABUNDANCES IN PTPS RED CLUMP GIANTS Monika Adamów 1, *, Andrzej Niedzielski 1,

More information

A spectroscopic hunt for binary RR Lyrae pulsators

A spectroscopic hunt for binary RR Lyrae pulsators A spectroscopic hunt for binary RR Lyrae pulsators Elisabeth Guggenberger Max Planck Institute for Solar System Research, Göttingen In collaboration with Thomas G. Barnes and Katrien Kolenberg Some Background

More information

College of San Mateo Observatory

College of San Mateo Observatory College of San Mateo Observatory Stellar Spectra Catalog SGS Spectrograph Spectra taken from CSM observatory using SBIG Self Guiding Spectrograph (SGS) A work in progress compiled by faculty, staff, and

More information

Analysis of the rich optical iron-line spectrum of the x-ray variable I Zw 1 AGN 1H

Analysis of the rich optical iron-line spectrum of the x-ray variable I Zw 1 AGN 1H Analysis of the rich optical iron-line spectrum of the x-ray variable I Zw 1 AGN 1H0707 495 H Winkler, B Paul Department of Physics, University of Johannesburg, PO Box 524, 2006 Auckland Park, Johannesburg,

More information

Lab 4: Stellar Spectroscopy

Lab 4: Stellar Spectroscopy Name:... Astronomy 101: Observational Astronomy Fall 2006 Lab 4: Stellar Spectroscopy 1 Observations 1.1 Objectives and Observation Schedule During this lab each group will target a few bright stars of

More information

V. Astronomy Section

V. Astronomy Section EAS 100 Planet Earth Lecture Topics Brief Outlines V. Astronomy Section 1. Introduction, Astronomical Distances, Solar System Learning objectives: Develop an understanding of Earth s position in the solar

More information

Introduction to SDSS -instruments, survey strategy, etc

Introduction to SDSS -instruments, survey strategy, etc Introduction to SDSS -instruments, survey strategy, etc (materials from http://www.sdss.org/) Shan Huang 17 February 2010 Survey type Status Imaging and Spectroscopy Basic Facts SDSS-II completed, SDSS-III

More information

Radial Velocity Variations in ι Herculis. Christopher L. Mulliss

Radial Velocity Variations in ι Herculis. Christopher L. Mulliss A Thesis entitled Radial Velocity Variations in ι Herculis by Christopher L. Mulliss As partial fulfillment of the requirements for the Master of Science Degree in Physics Advisor : Dr. N. D. Morrison

More information

Lecture 25: The Cosmic Distance Scale Sections 25-1, 26-4 and Box 26-1

Lecture 25: The Cosmic Distance Scale Sections 25-1, 26-4 and Box 26-1 Lecture 25: The Cosmic Distance Scale Sections 25-1, 26-4 and Box 26-1 Key Ideas The Distance Problem Geometric Distances Trigonometric Parallaxes Luminosity Distances Standard Candles Spectroscopic Parallaxes

More information

High resolution spectroscopy of two metal-poor red giants: HD and HD

High resolution spectroscopy of two metal-poor red giants: HD and HD High resolution spectroscopy of two metal-poor red giants: HD 3078 and HD 1873 Faculty of Physics and Mathematics, University of Latvia, Raiņa bulv. 19, Riga, LV-1586, Latvia E-mail: arturs_ lv@inbox.lv

More information

Observingwith a LISA spectrograph. David Boyd BAAVSS, AAVSO, CBA

Observingwith a LISA spectrograph. David Boyd BAAVSS, AAVSO, CBA Observingwith a LISA spectrograph David Boyd BAAVSS, AAVSO, CBA For me, the appeal of spectroscopy is in its scientific potential Photometry reveals changes in a star s brightness R Scutum Spectroscopy

More information

JINA Observations, Now and in the Near Future

JINA Observations, Now and in the Near Future JINA Observations, Now and in the Near Future Timothy C. Beers Department of Physics & Astronomy Michigan State University & JINA: Joint Institute for Nuclear Astrophysics Examples SDSS-I, II, and III

More information

Relativity and Astrophysics Lecture 15 Terry Herter. RR Lyrae Variables Cepheids Variables Period-Luminosity Relation. A Stellar Properties 2

Relativity and Astrophysics Lecture 15 Terry Herter. RR Lyrae Variables Cepheids Variables Period-Luminosity Relation. A Stellar Properties 2 Stellar Properties Relativity and Astrophysics Lecture 15 Terry Herter Outline Spectroscopic Parallax Masses of Stars Periodic Variable Stars RR Lyrae Variables Cepheids Variables Period-Luminosity Relation

More information

A Spectral Atlas of F and G Stars

A Spectral Atlas of F and G Stars Chin. J. Astron. Astrophys. Vol. 4 (2004), No. 3, 279 283 ( http: /www.chjaa.org or http: /chjaa.bao.ac.cn ) Chinese Journal of Astronomy and Astrophysics A Spectral Atlas of F and G Stars V. G. Klochkova

More information

OGLE-TR-56. Guillermo Torres, Maciej Konacki, Dimitar D. Sasselov and Saurabh Jha INTRODUCTION

OGLE-TR-56. Guillermo Torres, Maciej Konacki, Dimitar D. Sasselov and Saurabh Jha INTRODUCTION OGLE-TR-56 Guillermo Torres, Maciej Konacki, Dimitar D. Sasselov and Saurabh Jha Harvard-Smithsonian Center for Astrophysics Caltech, Department of Geological and Planetary Sciences University of California

More information

Optical/IR Observational Astronomy Spectroscopy. David Buckley, SALT

Optical/IR Observational Astronomy Spectroscopy. David Buckley, SALT David Buckley, SALT 1 Background is really just monochromatic photometry History 1637 Descartes explained the origin of the rainbow. 1666 Newton s classic experiments on the nature of colour. 1752 Melvil

More information

BRASS. The Belgian Repository of fundamental Atomic data and Stellar Spectra. Contact day meeting 19th September 2017

BRASS. The Belgian Repository of fundamental Atomic data and Stellar Spectra. Contact day meeting 19th September 2017 Contact day meeting 19th September 2017 mike.laverick@kuleuven.be BRASS The Belgian Repository of fundamental Atomic data and Stellar Spectra Mike Laverick Thibault Merle Alex Lobel Pierre Royer Christophe

More information

Objectives: (a) To understand how to display a spectral image both as an image and graphically.

Objectives: (a) To understand how to display a spectral image both as an image and graphically. Texas Tech University Department of Physics & Astronomy Astronomy 2401 Observational Astronomy Lab 8:- CCD Image Analysis:- Spectroscopy Objectives: There are two principle objectives for this laboratory

More information

Southern African Large Telescope

Southern African Large Telescope Southern African Large Telescope Title: Author(s): HRS pipeline for MR red-arm data with MIDAS Alexei Kniazev Doc. number: HRS0000003 Version: 1.0 Date: August 14, 2016 Keywords: HRS, Pipeline Approved:

More information

The IRS Flats. Spitzer Science Center

The IRS Flats. Spitzer Science Center Spitzer Science Center Table of Contents The IRS Flats 1 Chapter 1. The Purpose of this Document... 3 Chapter 2.... 4 2.1 Make a finely-spaced map of a star....4 2.2 Simulate an extended source...6 2.3

More information

arxiv: v2 [astro-ph.ep] 2 Nov 2017

arxiv: v2 [astro-ph.ep] 2 Nov 2017 Palomar Optical Spectrum of Hyperbolic Near-Earth Object A/2017 U1 Joseph R. Masiero 1 ABSTRACT arxiv:1710.09977v2 [astro-ph.ep] 2 Nov 2017 We present optical spectroscopy of the recently discovered hyperbolic

More information

The variable nature of the OB star HD13831 Dr. Amira Val Baker. Celebrating Ten Years of Science with STELLA Wednesday 9th November 2016

The variable nature of the OB star HD13831 Dr. Amira Val Baker. Celebrating Ten Years of Science with STELLA Wednesday 9th November 2016 The variable nature of the OB star HD13831 Dr. Amira Val Baker Celebrating Ten Years of Science with STELLA Wednesday 9th November 2016 STELLA robotic telescope Dr Ana Gonzales-Galan Celebrating Ten Years

More information

Infrared Spectroscopy of the Black Hole Candidate GRO J

Infrared Spectroscopy of the Black Hole Candidate GRO J Infrared Spectroscopy of the Black Hole Candidate GRO J1655-40 1 Francis T. O Donovan March 19th, 2004 1 Based on a paper by F. T. O Donovan & P. J. Callanan (in preparation). Black Holes in the Sky At

More information

(Present and) Future Surveys for Metal-Poor Stars

(Present and) Future Surveys for Metal-Poor Stars (Present and) Future Surveys for Metal-Poor Stars Timothy C. Beers Department of Physics & Astronomy Michigan State University & JINA: Joint Institute for Nuclear Astrophysics SDSS 1 Why the Fascination

More information

DETERMINATION OF STELLAR ROTATION WITH GAIA AND EFFECTS OF SPECTRAL MISMATCH. A. Gomboc 1,2, D. Katz 3

DETERMINATION OF STELLAR ROTATION WITH GAIA AND EFFECTS OF SPECTRAL MISMATCH. A. Gomboc 1,2, D. Katz 3 537 DETERMINATION OF STELLAR ROTATION WITH GAIA AND EFFECTS OF SPECTRAL MISMATCH A. Gomboc,2, D. Katz 3 University in Ljubljana, Jadranska 9, 00 Ljubljana, Slovenia 2 ARI, Liverpool John Moores University,

More information

Study of Physical Characteristics of High Apogee Space Debris

Study of Physical Characteristics of High Apogee Space Debris Study of Physical Characteristics of High Apogee Space Debris Yongna Mao, Jianfeng Wang, Xiaomeng Lu, Liang Ge, Xiaojun Jiang (National Astronomical Observatories, Beijing, 100012, China) Abstract Date

More information

The Stars. Chapter 14

The Stars. Chapter 14 The Stars Chapter 14 Great Idea: The Sun and other stars use nuclear fusion reactions to convert mass into energy. Eventually, when a star s nuclear fuel is depleted, the star must burn out. Chapter Outline

More information

Determining the Properties of the Stars

Determining the Properties of the Stars Determining the Properties of the Stars This set of notes by Nick Strobel covers: The properties of stars--their distances, luminosities, compositions, velocities, masses, radii, and how we determine those

More information

OPTION E, ASTROPHYSICS TEST REVIEW

OPTION E, ASTROPHYSICS TEST REVIEW IB PHYSICS Name: DEVIL PHYSICS Period: Date: BADDEST CLASS ON CAMPUS OPTION E, ASTROPHYSICS TEST REVIEW S1. This question is about the nature of certain stars on the Hertzsprung-Russell diagram and determining

More information

1 Introduction. 2 Observations. HD , an Eccentric Ellipsoidal System

1 Introduction. 2 Observations. HD , an Eccentric Ellipsoidal System Peremennye Zvezdy (Variable Stars) 33, No. 7, 2013 Received 24 August; accepted 30 August. HD 305629, an Eccentric Ellipsoidal System S. A. Otero 1,2, G. Di Scala 3,4 1 Buenos Aires, Argentina 2 American

More information

Extraction of Point Source Spectra from STIS Long Slit Data

Extraction of Point Source Spectra from STIS Long Slit Data 1997 HST Calibration Workshop Space Telescope Science Institute, 1997 S. Casertano, et al., eds. Extraction of Point Source Spectra from STIS Long Slit Data J. R. Walsh Spect Telescope European Coordinating

More information

arxiv: v2 [astro-ph.sr] 16 May 2013

arxiv: v2 [astro-ph.sr] 16 May 2013 Pulsation Analysis of the High Amplitude δ Scuti Star CW Serpentis J. S. Niu arxiv:1304.3770v2 [astro-ph.sr] 16 May 2013 Astronomy Department, Beijing Normal University, Beijing 100875, China J. N. Fu

More information

BRITE and Ground-based Photometry and Spectroscopy of the β Cephei Star ɛ Persei

BRITE and Ground-based Photometry and Spectroscopy of the β Cephei Star ɛ Persei BRITE and Ground-based Photometry and Spectroscopy of the β Cephei Star ɛ Persei Elżbieta Zoc lońska 1 and the BRITE Team 1. Nicolaus Copernicus Astronomical Center Bartycka 18, 00 716 Warszawa, Poland

More information

Sky Brightness at the Hobby-Eberly Telescope

Sky Brightness at the Hobby-Eberly Telescope Sky Brightness at the Hobby-Eberly Telescope D. Austin Belknap August 15, 2008 Abstract The Hobby-Eberly Telescope (HET) at McDonald Observatory has a 9.2 m effective aperture, and has been in operation

More information

Lecture 16 The Measuring the Stars 3/26/2018

Lecture 16 The Measuring the Stars 3/26/2018 Lecture 16 The Measuring the Stars 3/26/2018 Test 2 Results D C B A Questions that I thought were unfair: 13, 18, 25, 76, 77, 80 Curved from 85 to 79 Measuring stars How far away are they? How bright are

More information

Characterizing Stars

Characterizing Stars Characterizing Stars 1 Guiding Questions 1. How far away are the stars? 2. What evidence do astronomers have that the Sun is a typical star? 3. What is meant by a first-magnitude or second magnitude star?

More information

Characterizing Stars. Guiding Questions. Parallax. Careful measurements of the parallaxes of stars reveal their distances

Characterizing Stars. Guiding Questions. Parallax. Careful measurements of the parallaxes of stars reveal their distances Guiding Questions Characterizing Stars 1. How far away are the stars? 2. What evidence do astronomers have that the Sun is a typical star? 3. What is meant by a first-magnitude or second magnitude star?

More information

AG Draconis. A high density plasma laboratory. Dr Peter Young Collaborators A.K. Dupree S.J. Kenyon B. Espey T.B.

AG Draconis. A high density plasma laboratory. Dr Peter Young Collaborators A.K. Dupree S.J. Kenyon B. Espey T.B. AG Draconis A high density plasma laboratory Collaborators A.K. Dupree S.J. Kenyon B. Espey T.B. Ake p.r.young@rl.ac.uk Overview CHIANTI database Symbiotic Stars AG Draconis FUSE FUSE observations of AG

More information

OPTION E, ASTROPHYSICS TEST REVIEW

OPTION E, ASTROPHYSICS TEST REVIEW IB PHYSICS Name: DEVIL PHYSICS Period: Date: # Marks: XX Raw Score: IB Curve: BADDEST CLASS ON CAMPUS OPTION E, ASTROPHYSICS TEST REVIEW S1. This question is about the nature of certain stars on the Hertzsprung-Russell

More information

Comparing the Period-Luminosity relationships in variable stars

Comparing the Period-Luminosity relationships in variable stars Comparing the Period-Luminosity relationships in variable stars Daniela Romero Uppsala Universitet daniela.romero1230@gmail.com June 201 Abstract There are four Period Luminosity relations from three sources,

More information

The Galactic O-Star Spectral Survey (GOSSS) Project status and first results

The Galactic O-Star Spectral Survey (GOSSS) Project status and first results The Galactic O-Star Spectral Survey (GOSSS) Project status and first results Alfredo Sota 1, Jesús Maíz Apellániz 1, Rodolfo H. Barbá 2, Nolan R. Walborn 3, Emilio J. Alfaro 1, Roberto C. Gamen 4, Nidia

More information

PENNSYLVANIA SCIENCE OLYMPIAD STATE FINALS 2012 ASTRONOMY C DIVISION EXAM APRIL 27, 2012

PENNSYLVANIA SCIENCE OLYMPIAD STATE FINALS 2012 ASTRONOMY C DIVISION EXAM APRIL 27, 2012 PENNSYLVANIA SCIENCE OLYMPIAD STATE FINALS 2012 ASTRONOMY C DIVISION EXAM APRIL 27, 2012 TEAM NUMBER SCHOOL NAME INSTRUCTIONS: 1. Turn in all exam materials at the end of this event. Missing exam materials

More information

The Pulsation Properties of the Double-Mode RR Lyrae Variable V79 in Messier 3

The Pulsation Properties of the Double-Mode RR Lyrae Variable V79 in Messier 3 336 The Pulsation Properties of the Double-Mode RR Lyrae Variable V79 in Messier 3 Christine M. Clement Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON, M5S 3H8, Canada Mike

More information

The null result of a search for pulsational variations of the surface magnetic field in the roap star γ Equulei

The null result of a search for pulsational variations of the surface magnetic field in the roap star γ Equulei Mon. Not. R. Astron. Soc. 351, L34 L38 (2004) doi:10.1111/j.1365-2966.2004.07946.x The null result of a search for pulsational variations of the surface magnetic field in the roap star γ Equulei O. Kochukhov,

More information

Differential abundances in the HAT-P-4 binary system

Differential abundances in the HAT-P-4 binary system Differential abundances in the HAT-P-4 binary system Carlos Saffe 1,4, Emiliano Jofré 2,4, Eder Martioli 3 Matías Flores 1,4, Romina Petrucci 2,4 & Marcelo Jaque 1,4 (1) Instituto de Ciencias Astronómicas,

More information

23 New Variable Stars

23 New Variable Stars 350 23 New Variable Stars Clark, JAAVSO Volume 42, 2014 Maurice Clark Texas Tech University, Physics Department, P.O. Box 41051, Lubbock, TX 79409; maurice.clark@ttu.edu Received May 20, 2014, accepted

More information

Studies of diffuse UV radiation

Studies of diffuse UV radiation Bull. Astr. Soc. India (2007) 35, 295 300 Studies of diffuse UV radiation N. V. Sujatha and Jayant Murthy Indian Institute of Astrophysics, Bangalore 560 034, India Abstract. The upcoming TAUVEX mission

More information

High-dispersion Spectroscopic Observations of the T Tauri-type Stars with Weak Emission Lines

High-dispersion Spectroscopic Observations of the T Tauri-type Stars with Weak Emission Lines ELSEVIER Chinese Astronomy and Astrophysics 37 (2013) 418 427 CHINESE ASTRONOMY AND ASTROPHYSICS High-dispersion Spectroscopic Observations of the T Tauri-type Stars with Weak Emission Lines XING Li-feng

More information

A Fast Algorithm for Cosmic Rays Removal from Single Images

A Fast Algorithm for Cosmic Rays Removal from Single Images A Fast Algorithm for Cosmic Rays Removal from Single Images Wojtek Pych David Dunlap Observatory, University of Toronto P.O. Box 360, Richmond Hill, Ontario, Canada L4C 4Y6 and Copernicus Astronomical

More information

Mass transfer in Binary-System VV Cep

Mass transfer in Binary-System VV Cep Mass transfer in Binary-System VV Cep Fig: 1 Two of the best known and largest stars in space, which can be found hidden and close together within a dark interstellar cloud of dust in the constellation

More information

Variable Stars Advanced Lab

Variable Stars Advanced Lab Variable Stars Advanced Lab Introduction In this lab, you will be observing several variable stars to determine the period and classification of the star. A variable star is considered any star which goes

More information

Types of Stars and the HR diagram

Types of Stars and the HR diagram Types of Stars and the HR diagram Full window version (looks a little nicer). Click button to get back to small framed version with content indexes. This material (and images) is copyrighted! See

More information

Astronomical Techniques

Astronomical Techniques Astronomical Techniques Spectrographs & Spectroscopy Spectroscopy What is spectroscopy? A little history. What can we learn from spectroscopy? Play with simple spectrographs. Basic optics of a spectrograph.

More information

Abundance of Elements. Relative abundance of elements in the Solar System

Abundance of Elements. Relative abundance of elements in the Solar System Abundance of Elements Relative abundance of elements in the Solar System What is the origin of elements in the universe? Three elements formed in the first minutes after the big bang (hydrogen, helium

More information

Physics and Chemistry of the Interstellar Medium

Physics and Chemistry of the Interstellar Medium Physics and Chemistry of the Interstellar Medium Sun Kwok The University of Hong Kong UNIVERSITY SCIENCE BOOKS Sausalito, California * Preface xi The Interstellar Medium.1.1 States of Matter in the ISM

More information

Astronomical Spectroscopy Introduction PMO David Haworth Copyright 2014

Astronomical Spectroscopy Introduction PMO David Haworth  Copyright 2014 Astronomical Spectroscopy Introduction PMO 2014 David Haworth www.stargazing.net/david Copyright 2014 Astronomical Spectroscopy Astrophysics Quantum Mechanics Electromagnetic spectrum provides insight

More information

Spectroscopic observations of new Oort cloud comet 2006 VZ13 and four other comets

Spectroscopic observations of new Oort cloud comet 2006 VZ13 and four other comets Mon. Not. R. Astron. Soc. 401, 2399 2405 (2010) doi:10.1111/j.1365-2966.2009.15822.x Spectroscopic observations of new Oort cloud comet 2006 VZ13 and four other comets A. M. Gilbert, 1 P. A. Wiegert, 1

More information

ASTROPHYSICS. K D Abhyankar. Universities Press S T A R S A ND G A L A X I E S

ASTROPHYSICS. K D Abhyankar. Universities Press S T A R S A ND G A L A X I E S ASTROPHYSICS S T A R S A ND G A L A X I E S K D Abhyankar Universities Press Contents Foreword vii Preface ix 1 Introduction 1 1.1 ' Astronomy and astrophysics 1 1.2 Importance of astronomy 2 1.3 Methods

More information

The Challenge of AZ Cas-Part 1. John Menke Barnesville, MD Abstract

The Challenge of AZ Cas-Part 1. John Menke Barnesville, MD Abstract The Challenge of AZ Cas-Part 1 John Menke Barnesville, MD 20838 john@menkescientific.com www.menkescientific.com Abstract This is an interim report on observations of the spectrum of AZCas taken during

More information

Discovery of Pulsating Components in the Southern Eclipsing Binary Systems AW Velorum, HM Puppis, and TT Horologii

Discovery of Pulsating Components in the Southern Eclipsing Binary Systems AW Velorum, HM Puppis, and TT Horologii 182 Discovery of Pulsating Components in the Southern Eclipsing Binary Systems AW Velorum, HM Puppis, and TT Horologii David J. W. Moriarty 315 Main Road, Wellington Point, Queensland 4160, Australia;

More information

Galac%c Unprecedented Precision (0.01 dex)

Galac%c Unprecedented Precision (0.01 dex) Li Be B Si O Fe Dy Ce Ru Y Pb C a Ti L V b Y Eu Al N Pr d Sr Mo Ba P Ca K Cr S N Sm Gd U Ag Pd Mg Ni Galac%c Archaeology @ Unprecedented Precision (0.01 dex) @DrJorgeMelendez Dep. Astronomia, Univ. São

More information

arxiv:astro-ph/ v1 12 Nov 2003

arxiv:astro-ph/ v1 12 Nov 2003 A Fast Algorithm for Cosmic Rays Removal from Single Images Wojtek Pych arxiv:astro-ph/0311290v1 12 Nov 2003 David Dunlap Observatory, University of Toronto P.O. Box 360, Richmond Hill, Ontario, Canada

More information

NAOYUKI TAMURA Subaru Instrument Astronomer Subaru Telescope, NAOJ

NAOYUKI TAMURA Subaru Instrument Astronomer Subaru Telescope, NAOJ FMOS status tt report Science workshop 2011.02.2802 28-03.0202 NAOYUKI TAMURA Subaru Instrument Astronomer Subaru Telescope, NAOJ * Overview * Recent history & current status t * Schedule & future plan

More information

Astr 5465 Feb. 6, 2018 Today s Topics

Astr 5465 Feb. 6, 2018 Today s Topics Astr 5465 Feb. 6, 2018 Today s Topics Stars: Binary Stars Determination of Stellar Properties via Binary Stars Classification of Binary Stars Visual Binaries Both stars visible Only one star visible Spectroscopic

More information

The Hertzprung-Russell Diagram. The Hertzprung-Russell Diagram. Question

The Hertzprung-Russell Diagram. The Hertzprung-Russell Diagram. Question Key Concepts: Lecture 21: Measuring the properties of stars (cont.) The Hertzsprung-Russell (HR) Diagram (L versus T) The Hertzprung-Russell Diagram The Stefan-Boltzmann Law: flux emitted by a black body

More information

Thorium (Th) Enrichment in the Milky Way Galaxy

Thorium (Th) Enrichment in the Milky Way Galaxy Thorium (Th) Enrichment in the Milky Way Galaxy National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan E-mail: aoki.wako@nao.ac.jp Satoshi Honda Kwasan Observatory, Kyoto

More information

arxiv:astro-ph/ v1 23 Oct 2002

arxiv:astro-ph/ v1 23 Oct 2002 Evolution of the symbiotic nova RX Puppis J. Mikołajewska, E. Brandi, L. Garcia, O. Ferrer, C. Quiroga and G.C. Anupama arxiv:astro-ph/0210505v1 23 Oct 2002 N. Copernicus Astronomical Center, Bartycka

More information

Photometric and spectroscopic observations of the 2014 eclipse of the complex binary EE Cephei

Photometric and spectroscopic observations of the 2014 eclipse of the complex binary EE Cephei Photometric and spectroscopic observations of the 2014 eclipse of the complex binary EE Cephei David Boyd Variable Star Section, British Astronomical Association, [davidboyd@orion.me.uk] Abstract We report

More information

Outline. c.f. Zhao et al. 2006, ChJA&A, 6, 265. Stellar Abundance and Galactic Chemical Evolution through LAMOST Spectroscopic Survey

Outline. c.f. Zhao et al. 2006, ChJA&A, 6, 265. Stellar Abundance and Galactic Chemical Evolution through LAMOST Spectroscopic Survey KIAA-CambridgeJoint Workshop on Near-Field Cosmology and Galactic Archeology ZHAO Gang National Astronomical Observatories, Chinese Academy of Sciences Dec 1-5, 2008 Beijing Outline LAMOST stellar spectroscopic

More information

Open Cluster Photometry: Part II

Open Cluster Photometry: Part II Project 4 Open Cluster Photometry: Part II Observational Astronomy ASTR 310 Fall 2005 1 Introduction The objective of this and the previous project is to learn how to produce color-magnitude diagrams of

More information

Fringe Correction for STIS Near-IR Long-Slit Spectra using Contemporaneous Tungsten Flat Fields

Fringe Correction for STIS Near-IR Long-Slit Spectra using Contemporaneous Tungsten Flat Fields 1997 HST Calibration Workshop Space Telescope Science Institute, 1997 S. Casertano, et al., eds. Fringe Correction for STIS Near-IR Long-Slit Spectra using Contemporaneous Tungsten Flat Fields Paul Goudfrooij

More information

Parallax: Measuring the distance to Stars

Parallax: Measuring the distance to Stars Measuring the Stars Parallax: Measuring the distance to Stars Use Earth s orbit as baseline Parallactic angle = 1/2 angular shift Distance from the Sun required for a star to have a parallactic angle of

More information

Chapter 12 Stellar Evolution

Chapter 12 Stellar Evolution Chapter 12 Stellar Evolution Guidepost This chapter is the heart of any discussion of astronomy. Previous chapters showed how astronomers make observations with telescopes and how they analyze their observations

More information

2019 Astronomy Team Selection Test

2019 Astronomy Team Selection Test 2019 Astronomy Team Selection Test Acton-Boxborough Regional High School Written by Antonio Frigo Do not flip over this page until instructed. Instructions You will have 45 minutes to complete this exam.

More information

Stars. The composition of the star It s temperature It s lifespan

Stars. The composition of the star It s temperature It s lifespan Stars Stars A star is a ball of different elements in the form of gases The elements and gases give off electromagnetic radiation (from nuclear fusion) in the form of light Scientists study the light coming

More information

The Keck Observatory Archive

The Keck Observatory Archive The Keck Observatory Archive http://nexsci.caltech.edu/archives/koa/ index.shtml A collaboration between NExScI and the W. M. Keck Observatory G. Bruce Berriman on behalf of the KOA team June 11, 2010

More information

GOODS/FORS2 Final Data Release: Version 3.0

GOODS/FORS2 Final Data Release: Version 3.0 ESO Phase 3 Data Release Description Data Collection GOODS_FORS2 Release Number 1 Data Provider C. Cesarsky Date 30.10.2007 update 11.07.2014 GOODS/FORS2 Final Data Release: Version 3.0 As part of the

More information

The Doppler Method, or Radial Velocity Detection of Planets: I. Technique

The Doppler Method, or Radial Velocity Detection of Planets: I. Technique ASTs309L The Doppler Method, or Radial Velocity Detection of Planets: I. Technique 1. Keplerian Orbits 2. Spectrographs/Doppler shifts 3. Precise Radial Velocity measurements ASTs309L The Doppler Effect:

More information

Comet Measurement Techniques. Karen Meech Institute for Astronomy Session 27 1/18/05

Comet Measurement Techniques. Karen Meech Institute for Astronomy Session 27 1/18/05 Comet Measurement Techniques Karen Meech Institute for Astronomy Session 27 1/18/05 Image copyright, R. Wainscoat, IfA Image courtesy K. Meech Techniques Summary Imaging & Detectors Photometry Deep Imaging

More information

Today in Astronomy 328: binary stars

Today in Astronomy 328: binary stars Today in Astronomy 38: binary stars Binary-star systems. Direct measurements of stellar mass and radius in eclipsing binary-star systems. At right: two young binary star systems in the Taurus star-forming

More information

The Milky Way Galaxy (ch. 23)

The Milky Way Galaxy (ch. 23) The Milky Way Galaxy (ch. 23) [Exceptions: We won t discuss sec. 23.7 (Galactic Center) much in class, but read it there will probably be a question or a few on it. In following lecture outline, numbers

More information

Southern African Large Telescope

Southern African Large Telescope Southern African Large Telescope Title: Author(s): HRS pipeline for LR red-arm data with MIDAS Alexei Kniazev Doc. number: HRS0000002 Version: 1.0 Date: July 29, 2016 Keywords: HRS, Pipeline Approved:

More information