Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09
We report three <i>RXTE</i>/PCA observations of the low-mass X-ray binary 4U 0614+09. They show strong (~30% rms) band-limited noise with a cutoff frequency varying between 0.7 and 15 Hz in correlation with the X-ray flux, fₓ. We observe two nonsimultaneous 11%-15% (rms) kHz peaks near 7...
Autores principales: | , , , , , , , |
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Formato: | Articulo |
Lenguaje: | Inglés |
Publicado: |
1997
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Materias: | |
Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/123162 |
Aporte de: |
id |
I19-R120-10915-123162 |
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record_format |
dspace |
institution |
Universidad Nacional de La Plata |
institution_str |
I-19 |
repository_str |
R-120 |
collection |
SEDICI (UNLP) |
language |
Inglés |
topic |
Astronomía accretion, accretion disks stars: individual (4U 06141091) stars: neutron X-rays: stars |
spellingShingle |
Astronomía accretion, accretion disks stars: individual (4U 06141091) stars: neutron X-rays: stars Méndez, Mariano R. Klis, M. van der Paradijs, J. van Lewin, Walter H. G. Lamb, Frederick K. Vaughan, Brian A. Kuulkers, Erik Psaltis, Dimitrios Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09 |
topic_facet |
Astronomía accretion, accretion disks stars: individual (4U 06141091) stars: neutron X-rays: stars |
description |
We report three <i>RXTE</i>/PCA observations of the low-mass X-ray binary 4U 0614+09. They show strong (~30% rms) band-limited noise with a cutoff frequency varying between 0.7 and 15 Hz in correlation with the X-ray flux, fₓ. We observe two nonsimultaneous 11%-15% (rms) kHz peaks near 728 and 629 Hz in the power spectra of two of our observations when fₓ ~ 10<sup>-9</sup> ergs cm⁻² s⁻¹ (2-10 keV) but find no quasi-periodic oscillations (QPOs; <6% rms) when fₓ is half that. We suggest that count rate may not be a good measure for dot Ṁ even in sources as intrinsically weak as 4U 0614+09 and that QPO frequency and noise cutoff frequency track dot Ṁ more closely than count rate. The QPO increases in rms amplitude from 11% ± 1.3% at 3 keV to 37% ± 12% at 23 keV; the fractional amplitude of the band-limited noise is energy independent. This suggests different sites of origin for these two phenomena. The spectrum of the oscillating flux roughly corresponds to a black body with temperature 1.56 ± 0.2 keV and radius 500 ± 200 m (other models fit as well), which might indicate that the oscillations originate at a small region on the neutron star surface. |
format |
Articulo Articulo |
author |
Méndez, Mariano R. Klis, M. van der Paradijs, J. van Lewin, Walter H. G. Lamb, Frederick K. Vaughan, Brian A. Kuulkers, Erik Psaltis, Dimitrios |
author_facet |
Méndez, Mariano R. Klis, M. van der Paradijs, J. van Lewin, Walter H. G. Lamb, Frederick K. Vaughan, Brian A. Kuulkers, Erik Psaltis, Dimitrios |
author_sort |
Méndez, Mariano R. |
title |
Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09 |
title_short |
Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09 |
title_full |
Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09 |
title_fullStr |
Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09 |
title_full_unstemmed |
Kilohertz Quasi-periodic Oscillation and Atoll Source States in 4U 0614+09 |
title_sort |
kilohertz quasi-periodic oscillation and atoll source states in 4u 0614+09 |
publishDate |
1997 |
url |
http://sedici.unlp.edu.ar/handle/10915/123162 |
work_keys_str_mv |
AT mendezmarianor kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT klismvander kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT paradijsjvan kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT lewinwalterhg kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT lambfrederickk kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT vaughanbriana kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT kuulkerserik kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 AT psaltisdimitrios kilohertzquasiperiodicoscillationandatollsourcestatesin4u061409 |
bdutipo_str |
Repositorios |
_version_ |
1764820449874673665 |