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Title: Analysis of the southern pre-contact W UMa binary ZZ Eridani: A 34 year period study yields a possible low-mass companion

Abstract

Complete Bessel BVRI light curves of ZZ Eridani [2MASS J04130109-1044545, HV 6280, NSVS 14888164 α(2000) = 04{sup h}13{sup m}1{sub ·}{sup s}10, δ(2000) = −10°44′54{sub ·}{sup ″}5 (ICRS), V = 13.9-14.4-15.0] are observed and analyzed. The system is a southern pre-contact W UMa binary. Its light curve has the appearance of an Algol (EA) light curve, however, it is made up of dwarf solar-type components with a period of only 0.4521 days. Our 34 year period study yields a sinusoidal fit or an increasing quadratic fit. The sinusoid may indicate that a third body is orbiting the close binary. The lower-limit mass of the third body is near that of the brown dwarf limit (0.095 M α). Also included is an improved ephemeris, a mass ratio search, and a simultaneous BVRI Wilson–Devinney solution.

Authors:
 [1];  [2];  [3];  [4]
  1. Faculty Research Associate, Pisgah Astronomical Research Institute, One Pari Drive, Rosman, NC 28772 (United States)
  2. Astronomy Group, Physics and Engineering Department, Bob Jones University, 1700 Wade Hampton Boulevard, Greenville, SC 29614 (United States)
  3. Physics Department, Florida International University, 11200 SW 8th Street, Miami, FL 33199 (United States)
  4. University of South Carolina, Lancaster, 476 Hubbard Drive Lancaster, SC 29720 (United States)
Publication Date:
OSTI Identifier:
22342129
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 149; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DIAGRAMS; ECLIPSE; ION CYCLOTRON-RESONANCE; MASS; STAR EVOLUTION; STARS; VISIBLE RADIATION

Citation Formats

Samec, R. G., Clark, J. D., Hamme, W. Van, and Faulkner, D. R. Analysis of the southern pre-contact W UMa binary ZZ Eridani: A 34 year period study yields a possible low-mass companion. United States: N. p., 2015. Web. doi:10.1088/0004-6256/149/2/48.
Samec, R. G., Clark, J. D., Hamme, W. Van, & Faulkner, D. R. Analysis of the southern pre-contact W UMa binary ZZ Eridani: A 34 year period study yields a possible low-mass companion. United States. doi:10.1088/0004-6256/149/2/48.
Samec, R. G., Clark, J. D., Hamme, W. Van, and Faulkner, D. R. 2015. "Analysis of the southern pre-contact W UMa binary ZZ Eridani: A 34 year period study yields a possible low-mass companion". United States. doi:10.1088/0004-6256/149/2/48.
@article{osti_22342129,
title = {Analysis of the southern pre-contact W UMa binary ZZ Eridani: A 34 year period study yields a possible low-mass companion},
author = {Samec, R. G. and Clark, J. D. and Hamme, W. Van and Faulkner, D. R.},
abstractNote = {Complete Bessel BVRI light curves of ZZ Eridani [2MASS J04130109-1044545, HV 6280, NSVS 14888164 α(2000) = 04{sup h}13{sup m}1{sub ·}{sup s}10, δ(2000) = −10°44′54{sub ·}{sup ″}5 (ICRS), V = 13.9-14.4-15.0] are observed and analyzed. The system is a southern pre-contact W UMa binary. Its light curve has the appearance of an Algol (EA) light curve, however, it is made up of dwarf solar-type components with a period of only 0.4521 days. Our 34 year period study yields a sinusoidal fit or an increasing quadratic fit. The sinusoid may indicate that a third body is orbiting the close binary. The lower-limit mass of the third body is near that of the brown dwarf limit (0.095 M α). Also included is an improved ephemeris, a mass ratio search, and a simultaneous BVRI Wilson–Devinney solution.},
doi = {10.1088/0004-6256/149/2/48},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 2,
volume = 149,
place = {United States},
year = 2015,
month = 2
}
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