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Full-Text Articles in Physical Sciences and Mathematics

Sun In The Spectroscopic Binary Im Pegasi, The Guide Star For The Gravity Probe B Mission, Stephen C. Marsden, Svetlana Berdyugina, Jean-Francois Donati, Joel A. Eaton, Michael H. Williamson, Ilya Ilyin, Debra A. Fischer, Melesio Muñoz, Howard Isaacson, M. I. Ratner, Meïr Semel, Pascal Petit, Brad D. Carter Nov 2005

Sun In The Spectroscopic Binary Im Pegasi, The Guide Star For The Gravity Probe B Mission, Stephen C. Marsden, Svetlana Berdyugina, Jean-Francois Donati, Joel A. Eaton, Michael H. Williamson, Ilya Ilyin, Debra A. Fischer, Melesio Muñoz, Howard Isaacson, M. I. Ratner, Meïr Semel, Pascal Petit, Brad D. Carter

Information Systems and Engineering Management Research Publications

We present the first detection of the secondary of the spectroscopic binary system IM Pegasi (HR 8703), the guide star for the NASA-Stanford relativity gyroscope mission Gravity Probe B. In support of this mission, high-resolution echelle spectra of IM Peg have been obtained on an almost nightly basis. Applying the technique of least-squares deconvolution, we achieve very high signal-to-noise ratio line profiles and detect the orbit of the secondary of the system. Combining almost 700 new radial velocity measurements of both the primary and secondary of the system with previous measurements, we derive improved orbital parameters of the IM Peg …


The N2k Consortium. Ii. A Transiting Hot Saturn Around Hd 149026 With A Large Dense Core, Bun'ei Sato, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, R. Paul Butler, Geoffrey W. Marcy, Steve Vogt, Peter Bodenheimer, Shigeru Ida, Eri Toyota, Aaron S. Wolf, Jeff A. Valenti, Louis J. Boyd, John A. Johnson, Jason T. Wright, Mark Ammons, Sarah E. Robinson, Jay Strader, Chris Mccarthy, Kok Leong Tah, Dante Minniti Nov 2005

The N2k Consortium. Ii. A Transiting Hot Saturn Around Hd 149026 With A Large Dense Core, Bun'ei Sato, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, R. Paul Butler, Geoffrey W. Marcy, Steve Vogt, Peter Bodenheimer, Shigeru Ida, Eri Toyota, Aaron S. Wolf, Jeff A. Valenti, Louis J. Boyd, John A. Johnson, Jason T. Wright, Mark Ammons, Sarah E. Robinson, Jay Strader, Chris Mccarthy, Kok Leong Tah, Dante Minniti

Information Systems and Engineering Management Research Publications

Doppler measurements from Subaru and Keck have revealed radial velocity variations in the V = 8.15, G0 IV star HD 149026 consistent with a Saturn-mass planet in a 2.8766 day orbit. Photometric observations at Fairborn Observatory have detected three complete transit events with depths of 0.003 mag at the predicted times of conjunction. HD 149026 is now the second-brightest star with a transiting extrasolar planet. The mass of the star, based on interpolation of stellar evolutionary models, is 1.3 ± 0.1 M☉; together with the Doppler amplitude K1 = 43.3 m s-1, we derive a planet mass M sin i …


System Parameters Of The Transiting Extrasolar Planet Hd 209458b, Robert A. Wittenmyer, William F. Welsh, Jerome A. Orosz, A. B. Schultz, Wayne Kinzel, M. Kochte, Frederick Bruhweiler, David Bennum, Gregory W. Henry, Geoffrey W. Marcy, Debra A. Fischer, R. Paul Butler, Steve Vogt Oct 2005

System Parameters Of The Transiting Extrasolar Planet Hd 209458b, Robert A. Wittenmyer, William F. Welsh, Jerome A. Orosz, A. B. Schultz, Wayne Kinzel, M. Kochte, Frederick Bruhweiler, David Bennum, Gregory W. Henry, Geoffrey W. Marcy, Debra A. Fischer, R. Paul Butler, Steve Vogt

Information Systems and Engineering Management Research Publications

We derive improved system parameters for the HD 209458 system using a model that simultaneously fits both photometric transit and radial velocity observations. The photometry consists of previous Hubble Space Telescope STIS and FGS observations, 12 I-band transits observed between 2001 and 2003 with the Mount Laguna Observatory 1 m telescope, and six Strömgren b + y transits observed between 2001 and 2004 with two of the Automatic Photometric Telescopes at Fairborn Observatory. The radial velocities were derived from Keck HIRES observations. The model properly treats the orbital dynamics of the system and thus yields robust and physically self-consistent solutions. …


A ~7.5 M⊕ Planet Orbiting The Nearby Star, Gj 876*, Eugenio Rivera, Jack J. Lissauer, R. Paul Butler, Geoffrey W. Marcy, Steve Vogt, Debra A. Fischer, Timothy M. Brown, Gregory Laughlin, Gregory W. Henry Oct 2005

A ~7.5 M⊕ Planet Orbiting The Nearby Star, Gj 876*, Eugenio Rivera, Jack J. Lissauer, R. Paul Butler, Geoffrey W. Marcy, Steve Vogt, Debra A. Fischer, Timothy M. Brown, Gregory Laughlin, Gregory W. Henry

Information Systems and Engineering Management Research Publications

High-precision, high-cadence radial velocity monitoring over the past 8 yr at the W. M. Keck Observatory reveals evidence for a third planet orbiting the nearby (4.69 pc) dM4 star GJ 876. The residuals of three-body Newtonian fits, which include GJ 876 and Jupiter-mass companions b and c, show significant power at a periodicity of 1.9379 days. Self-consistently fitting the radial velocity data with a model that includes an additional body with this period significantly improves the quality of the fit. These four-body (three-planet) Newtonian fits find that the minimum mass of companion "d" is m sin i = 5.89 ± …


Five New Multicomponent Planetary Systems, Steve Vogt, R. Paul Butler, Geoffrey W. Marcy, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson Oct 2005

Five New Multicomponent Planetary Systems, Steve Vogt, R. Paul Butler, Geoffrey W. Marcy, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson

Information Systems and Engineering Management Research Publications

We report Doppler measurements for six nearby G- and K-type main-sequence stars that show multiple low-mass companions, at least one of which has planetary mass. One system has three planets, the fourth triple-planet system known around a normal star, and another has an extremely low minimum mass of 18 M⊕. HD 128311 (K0 V) has two planets (one previously known) with minimum masses (M sin i) of 2.18MJ and 3.21MJ and orbital periods of 1.26 and 2.54 yr, suggesting a possible 2 : 1 resonance. For HD 108874 (G5 V), the velocities reveal two planets (one previously known) having minimum …


Chromospherically Active Stars. Xxv. Hd 144110=Ev Draconis, A Double-Lined Dwarf Binary, Francis C. Fekel, Gregory W. Henry, Ceteka Lewis Aug 2005

Chromospherically Active Stars. Xxv. Hd 144110=Ev Draconis, A Double-Lined Dwarf Binary, Francis C. Fekel, Gregory W. Henry, Ceteka Lewis

Information Systems and Engineering Management Research Publications

New spectroscopic and photometric observations of HD 144110 have been used to obtain an improved orbital element solution and determine some basic properties of the system. This chromospherically active, double-lined spectroscopic binary has an orbital period of 1.6714012 days and a circular orbit. We classify the components as G5 V and K0 V and suggest that they are slightly metal-rich. The photometric observations indicate that the rotation of HD 144110 is synchronous with the orbital period. Despite the short orbital period, no evidence of eclipses is seen in our photometry.


Eleven New Γ Doradus Stars, Gregory W. Henry, Francis C. Fekel, Stephen M. Henry Jun 2005

Eleven New Γ Doradus Stars, Gregory W. Henry, Francis C. Fekel, Stephen M. Henry

Information Systems and Engineering Management Research Publications

We present new high-dispersion spectroscopic and precise photometric observations to identify 11 new γ Doradus variables. Seven of these new γ Doradus stars appear to be single, three are primaries of single-lined binaries, and one has two distant visual companions; none are double-lined or close visual binaries. Several of the stars show spectroscopic line-profile and low-amplitude radial velocity variability indicative of pulsation. All 11 stars are photometrically variable with amplitudes between 8 and 93 mmag in Johnson B and periods between 0.398 and 2.454 days. One star is monoperiodic; the rest have between two and five independent periods. The variability …


Hd 8801: A Unique Single Am Star With Γ Doradus And Δ Scuti Pulsations, Gregory W. Henry, Francis C. Fekel Apr 2005

Hd 8801: A Unique Single Am Star With Γ Doradus And Δ Scuti Pulsations, Gregory W. Henry, Francis C. Fekel

Information Systems and Engineering Management Research Publications

We have discovered the first example of a star pulsating intrinsically with both γ Doradus and δ Scuti frequencies. The star, HD 8801, is an Am metallic-line star that appears to be single. Since the vast majority of Am stars are members of binary systems with periods less than 1000 days and also do not pulsate, HD 8801 possesses a very unusual, if not unique, combination of physical properties. Our photometry, acquired with an automatic telescope at Fairborn Observatory, resolves six independent pulsation periods between 0.048 and 0.404 days. The two longest periods lie within the range of γ Dor …


Chromospherically Active Stars. Xxiv. The Giant, Single-Lined Binaries Hd 37824, Hd 181809, And Hd 217188, Francis C. Fekel, Gregory W. Henry Mar 2005

Chromospherically Active Stars. Xxiv. The Giant, Single-Lined Binaries Hd 37824, Hd 181809, And Hd 217188, Francis C. Fekel, Gregory W. Henry

Information Systems and Engineering Management Research Publications

We have obtained spectroscopy and photometry of three chromospherically active, single-lined spectroscopic binaries, HD 37824 (V1149 Ori), HD 181809 (V4138 Sgr), and HD 217188 (AZ Psc). HD 37824 has a circular orbit with a period of 53.57 days. Its primary is a K0 III star, while the secondary is likely a G or K dwarf. HD 181809 has an orbit with a period of 13.04667 days and a low eccentricity of 0.040. The primary has a spectral type of K0 III-IV, and its secondary is probably an M dwarf. The orbit of HD 217188 has a period of 47.1209 days …


Long Period Variables In The Globular Cluster 47 Tuc: Radial Velocity Variations, Thomas Lebzelter, Peter R. Wood, Kenneth H. Hinkle, Richard R. Joyce, Francis C. Fekel Feb 2005

Long Period Variables In The Globular Cluster 47 Tuc: Radial Velocity Variations, Thomas Lebzelter, Peter R. Wood, Kenneth H. Hinkle, Richard R. Joyce, Francis C. Fekel

Information Systems and Engineering Management Research Publications

We present near infrared velocity curves for 12 long period variables (LPVs) in the globular cluster 47 Tuc (NGC 104). New light curves are also presented for these variables. Results are compared with the period-luminosity sequences occupied by the LPVs in the LMC. Sequence C variables (fundamental mode pulsators) have larger velocity amplitudes than sequence B variables (first overtone pulsators). We show that, at similar luminosities, higher mass loss rates are associated with larger pulsation amplitudes. One variable (V18) does not fit the normal period luminosity sequences and it has an unusually large amount of circumstellar dust, suggesting that it …


The N2k Consortium. I. A Hot Saturn Planet Orbiting Hd 88133, Debra A. Fischer, Gregory Laughlin, Paul Butler, Geoff W. Marcy, John Johnson, Greg Henry, Jeff Valenti, Steve Vogt, Mark Ammons, Sarah Robinson, Greg Spear, Jay Strader, Peter Driscoll, Abby Fuller, Teresa Johnson, Elizabeth Manrao, Chris Mccarthy, Melesio Muñoz, Kok Leong Tah, Jason Wright, Shigeru Ida, Bun'ei Sato, Eri Toyota, Dante Minniti Feb 2005

The N2k Consortium. I. A Hot Saturn Planet Orbiting Hd 88133, Debra A. Fischer, Gregory Laughlin, Paul Butler, Geoff W. Marcy, John Johnson, Greg Henry, Jeff Valenti, Steve Vogt, Mark Ammons, Sarah Robinson, Greg Spear, Jay Strader, Peter Driscoll, Abby Fuller, Teresa Johnson, Elizabeth Manrao, Chris Mccarthy, Melesio Muñoz, Kok Leong Tah, Jason Wright, Shigeru Ida, Bun'ei Sato, Eri Toyota, Dante Minniti

Information Systems and Engineering Management Research Publications

The N2K ("next 2000") consortium is carrying out a distributed observing campaign with the Keck, Magellan, and Subaru telescopes, as well as the automatic photometric telescopes of Fairborn Observatory, in order to search for short-period gas giant planets around metal-rich stars. We have established a reservoir of more than 14,000 main-sequence and subgiant stars closer than 110 pc, brighter than V = 10.5, and with 0.4 < B - V < 1.2. Because the fraction of stars with planets is a sensitive function of stellar metallicity, a broadband photometric calibration has been developed to identify a subset of 2000 stars with [Fe/H] > 0.1 dex for this survey. We outline the strategy and report the detection of a planet orbiting the metal-rich G5 IV star HD 88133 with a period of 3.41 days, semivelocity amplitude K = …


A Study Of Bright Southern Long Period Variables, Thomas Lebzelter, Kenneth H. Hinkle, Peter R. Wood, Richard R. Joyce, Francis C. Fekel Feb 2005

A Study Of Bright Southern Long Period Variables, Thomas Lebzelter, Kenneth H. Hinkle, Peter R. Wood, Richard R. Joyce, Francis C. Fekel

Information Systems and Engineering Management Research Publications

In this paper we present radial velocity curves of AGB variables that exhibit various kinds of anomalies: semiregular variables (SRVs) with typical mira periods, SRVs exceeding the mira 2.5 mag amplitude limit, miras with secondary maxima in their light curves, and a SRV with a long secondary period. The stars with reliable Hipparcos parallaxes from this and from previous studies are plotted in a -diagram. Our objects nicely follow the -relations determined for the LMC. This allows the pulsation mode to be identified. While all miras fall on the fundamental mode sequence, the SRVs fall on both the first overtone …


Hd 166181 = V815 Herculis, A Single-Lined Spectroscopic Multiple System, Francis C. Fekel, David J. Barlow, Colin D. Scarfe, Sylvie Jancart, Dimitri Pourbaix Feb 2005

Hd 166181 = V815 Herculis, A Single-Lined Spectroscopic Multiple System, Francis C. Fekel, David J. Barlow, Colin D. Scarfe, Sylvie Jancart, Dimitri Pourbaix

Information Systems and Engineering Management Research Publications

We have obtained extensive spectroscopic and velocity spectrometer observations of HD 166181, a previously known single-lined spectroscopic binary. Our improved orbit for the G6 V primary has a period of 1.8098343 days and is circular. Although the lines of additional components have not been detected, radial velocity measurements confirm that the system has additional velocity variations with a period of 2092 days, or 5.73 yr. This long-period orbit has an eccentricity of 0.76. An analysis of the Hipparcos observations produces a well-determined astrometric orbit for the long-period system that has an inclination of 78°. Mass estimates of the components in …


Five New Extrasolar Planets, Geoffrey W. Marcy, R. Paul Butler, Steve Vogt, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson Jan 2005

Five New Extrasolar Planets, Geoffrey W. Marcy, R. Paul Butler, Steve Vogt, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, Jason T. Wright, John A. Johnson

Information Systems and Engineering Management Research Publications

We report multiple Doppler measurements of five nearby FGK main-sequence stars and subgiants obtained during the past 4-6 yr at the Keck Observatory. These stars, namely, HD 183263, HD 117207, HD 188015, HD 45350, and HD 99492, all exhibit coherent variations in their Doppler shifts consistent with a planet in Keplerian motion. The five new planets occupy known realms of planetary parameter space, including a wide range of orbital eccentricities, e = 0-0.78, and semimajor axes, 0.1-3.8 AU, that provide further statistical information about the true distributions of various properties of planetary systems. One of the planets, HD 99492b, has …