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. =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: ------------------------------------------------- RA (2000) DE Designation(s) ------------------------------------------------- 20 32 25.8 +40 57 28 Cyg X-3 = V* V1521 Cyg ------------------------------------------------- File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file tablea1.dat 79 135 The hardness-intensity diagram (HID) of Cyg X-3 -------------------------------------------------------------------------------- See also: J/MNRAS/308/473 : Cygnus X-3 IR spectra (Fender+, 1999) Byte-by-byte Description of file: tablea1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 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) -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Patricia Vannier [CDS] 23-Dec-2010