J/MNRAS/406/307 Radio variations of Cygnus X-3 (Koljonen+, 2010)
The hardness-intensity diagram of Cygnus X-3: revisiting the radio/X-ray states.
Koljonen K.I.I., Hannikainen D.C., McCollough M.L., Pooley G.G.,
Trushkin S.A.
<Mon. Not. R. Astron. Soc., 406, 307-319 (2010)>
=2010MNRAS.406..307K 2010MNRAS.406..307K
ADC_Keywords: Binaries, X-ray ; Radio sources
Keywords: accretion, accretion discs - binaries: close - X-rays: binaries -
X-rays: individual: Cygnus X-3 - X-rays: stars
Abstract:
Cygnus X-3 is one of the brightest X-ray and radio sources in the
Galaxy and is well known for its erratic behaviour in X-rays as well
as in the radio, occasionally producing major radio flares associated
with relativistic ejections. However, even after many years of
observations in various wavelength bands Cyg X-3 still eludes
clear physical understanding. Studying different emission bands
simultaneously in microquasars has proved to be a fruitful approach
towards understanding these systems, especially by shedding light
on the accretion disc/jet connection. We continue this legacy by
constructing a hardness-intensity diagram (HID) from archival Rossi
X-ray Timing Explorer data and linking simultaneous radio observations
to it. We find that surprisingly Cyg X-3 sketches a similar shape in
the HID to that seen in other transient black hole X-ray binaries
during outburst but with distinct differences.
Description:
We have analysed, following standard procedures using FTOOLS v6.5, 135
archive RXTE observations for the HID. The observations are listed in
Table A1 together with exposure times of the Proportional Counter
Array (PCA) and High Energy X-ray Timing Experiment (HEXTE) as well as
corresponding radio/X-ray states and radio flux during or near the
observation in question (maximum of half a day offset).
Objects:
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RA (2000) DE Designation(s)
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20 32 25.8 +40 57 28 Cyg X-3 = V* V1521 Cyg
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 79 135 The hardness-intensity diagram (HID) of Cyg X-3
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See also:
J/MNRAS/308/473 : Cygnus X-3 IR spectra (Fender+, 1999)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Sequential number of observation
5- 19 A15 --- ObsID ObsID
21- 30 A10 "YYYY/MM/DD" Date Observation date
32- 40 F9.3 d MJD1 MJD interval
41 A1 --- --- [-]
42- 50 F9.3 d MJD2 MJD interval
52- 55 F4.1 ks tPCA RXTE/PCA exposure time
57- 59 F3.1 ks tHEXTE RXTE/HEXTE exposure time
61- 70 A10 --- State X-ray/Radio state (1)
72- 76 F5.3 Jy Srad ?=- Mean radio flux (during or near the
RXTE observations) at8.3, 11.2 or 15GHz
78- 79 A2 --- n_Srad Frequency used (2)
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Note (1): Codes as follows:
Q = quiescent state
T = transition
FHXR = flaring/hard X-ray
FIM = flaring/intermediate
FSXR = flaring/soft X-ray
HYS = hypersoft state
Note (2): Notes as follows:
Ry = Ryle 15GHz
G = GBI 8.3GHz
RA = RATAN-600 11.2GHz
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 23-Dec-2010