The 8 second optical quasi-periodic oscillations in GX 339 - 4

Journal Article · Sat Dec 01 00:00:00 EST 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/169484· OSTI ID:6105506

Imamura, J N; Kristian, J; Middleditch, J; Steiman-Cameron, T Y ^[1]

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1. Oregon Univ., Eugene (USA) Observatories of the Carnegie Institution, Pasadena, CA (USA) Los Alamos National Lab., NM (USA) NASA, Ames Research Center, Moffett Field, CA (USA)

Submillisecond optical photometry of the black hole candidate GX 339 - 4 was obtained on August 1, 1989, (UT) using the 1.5 m telescope of the Cerro Tololo Inter-American Observatory. Eight second quasi-periodic oscillations of width 0.02-0.04 Hz and root mean square amplitude 4-6 percent are found. The visual magnitude of GX 339 - 4 at the beginning of the observation was m(v) = 17.7. Motch et al. (1985) have previously reported 7 s optical quasi-periodic oscillations when GX 339 - 4 was also m(v) = 17.7 and in an X-ray off-state. No X-ray observations were made during the present optical observations and so the X-ray state of GX 339 - 4 cannot be ascertained. In addition, Motch et al. have also reported 20 s optical quasi-periodic oscillations with 30-40 percent full amplitude but when GX 339 - 4 was much brighter, m(v) = 15.4, and in a hard X-ray state. 16 refs.

• OSTI ID: 6105506
• Journal Information: Astrophysical Journal; (USA), Vol. 365; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BLACK HOLES
PHOTOMETRY
VISIBLE RADIATION
ACCRETION DISKS
BINARY STARS
COSMIC X-RAY SOURCES
EMISSION SPECTRA
OSCILLATIONS
X RADIATION
COSMIC RAY SOURCES
ELECTROMAGNETIC RADIATION
IONIZING RADIATIONS
RADIATIONS
SPECTRA
STARS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources