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Title: Astrometry, radial velocity, and photometry: the HD 128311 system remixed with data from HST, HET, and APT

We have used high-cadence radial velocity measurements from the Hobby-Eberly Telescope with published velocities from the Lick 3 m Shane Telescope, combined with astrometric data from the Hubble Space Telescope (HST) Fine Guidance Sensors to refine the orbital parameters of the HD 128311 system, and determine an inclination of 55.°95 ± 14.°55 and true mass of 3.789 {sub −0.432}{sup +0.924} M {sub JUP} for HD 128311 c. The combined radial velocity data also reveal a short period signal which could indicate a third planet in the system with an Msin i of 0.133 ± 0.005 M {sub JUP} or stellar phenomena. Photometry from the T12 0.8 m automatic photometric telescope at the Fairborn Observatory and HST are used to determine a photometric period close to, but not within the errors of the radial velocity signal. We performed a cross-correlation bisector analysis of the radial velocity data to look for correlations with the photometric period and found none. Dynamical integrations of the proposed system show long-term stability with the new orbital parameters of over 10 million years. Our new orbital elements do not support the claims of HD 128311 b and c being in mean motion resonance.
Authors:
; ;  [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6]
  1. McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States)
  2. Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Blvd., P.O. Box 9501, Nashville, TN 37209 (United States)
  3. Thüringer Landessternwarte, Sternwarte 5, D-07778 Tautenburg (Germany)
  4. Department of Astronomy, New Mexico State, Las Cruces, NM 88003 (United States)
  5. Department of Physics and Astronomy, Rice University, MS-108, 6100 Main Street, Houston, TX 77005 (United States)
  6. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
Publication Date:
OSTI Identifier:
22370323
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 795; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CORRELATIONS; EVOLUTION; INCLINATION; MASS; PHOTOMETRY; PLANETS; RADIAL VELOCITY; SATELLITES; SPACE; STABILITY; STARS; TELESCOPES