13 3 v 1 6 M ar 2 00 3 The complete Z - diagram of LMC X – 2
نویسندگان
چکیده
We present results from four Rossi X-ray Timing Explorer (RXTE) observations of the bright low mass X-ray binary LMC X–2. During these observations, which span a year and include over 160 hrs of data, the source exhibits clear evolution through three branches on its hardness-intensity and color-color diagrams, consistent with the flaring, normal, and horizontal branches (FB, NB, HB) of a Z-source, and remarkably similar to Z-tracks derived for GX 17+2, Sco X–1 and GX 349+2. LMC X–2 was observed in the FB, NB, and HB for roughly 30%, 40%, and 30% respectively of the total time covered. The source traces out the full extent of the Z in ∼1 day, and the Z-track shows evidence for secular shifts on a timescale in excess of a few days. Although the count rate of LMC X–2 is low compared with the other known Z-sources due to its greater distance, the power density spectra selected by branch show very-low-frequency noise characteristics at least consistent with those from other Z-sources. We thus confirm the identification of LMC X–2 as a Z-source, the first identified outside our Galaxy.
منابع مشابه
ar X iv : h ep - p h / 06 08 16 2 v 1 1 4 A ug 2 00 6 Z ( 3 ) - symmetric effective theory for pure gauge QCD at high temperature
We review the construction and basic properties of a three-dimensional effective field theory for high-temperature SU(3) Yang-Mills theory, which respects its center symmetry and was introduced in Ref. [1]. We explain why the phase diagram of the new theory is expected to closely resemble the one of the full theory and argue that this implies that it is applicable down to considerably lower tem...
متن کاملar X iv : a st ro - p h / 99 07 30 3 v 1 2 2 Ju l 1 99 9 LMC X – 2 : The First Extragalactic Z - Source ? Alan
We present RXTE observations of LMC X–2 obtained during a five-day interval in 1997 December, during which the source was radiating at a mean intensity near the Eddington limit, and strongly variable on timescales of seconds to hours. The shapes of the X-ray color-color and hardness-intensity diagrams during the observations, the presence of VLFN and HFN in the power spectra, and the high intri...
متن کاملar X iv : h ep - l at / 0 40 30 27 v 1 2 7 M ar 2 00 4 A Gauge Theory of Wilson Lines as a Dimensionally Reduced Model of QCD
We investigate numerically and in the one loop approximation a two dimensional SU(3) gauge model of Wilson lines. We propose this model to be a dimensionally reduced model of high temperature QCD 3. In contrast to perturbative dimensional reduction it has an explicit global Z 3 symmetry in the action, and a confinement-deconfinement transition. The phase diagram of the model also shows a new th...
متن کاملar X iv : a st ro - p h / 00 02 21 9 v 1 1 0 Fe b 20 00 Changes in the long term intensity variations in Cyg X - 2 and LMC X - 3
We report the detection of changes in the long term intensity variations in two X-ray binaries Cyg X-2 and LMC X-3. In this work, we have used the long term light curves obtained with the All Sky Monitors (ASM) of the Rossi X-ray Timing Explorer (RXTE), GINGA, ARIEL 5 and VELA 5B and scanning modulation collimator of HEAO 1. It is found that in the light curves of both the sources, obtained wit...
متن کامل32 2 v 1 2 0 M ar 2 00 1 X - ray and UV Orbital Phase Dependence in LMC X – 3 Patricia
The black-hole binary LMC X–3 is known to be variable on time scales of days to years. We investigate X-ray and ultraviolet variability in the system as a function of the 1.7 day binary phase using a 6.4 day observation with the Rossi X-ray Timing Explorer (RXTE) from December 1998. An abrupt 14% flux decrease, lasting nearly an entire orbit, is followed by a return to previous flux levels. Thi...
متن کامل