J/A+A/458/21 INTEGRAL burst observations of 4U 1728-34 (Falanga+, 2006)
The X-ray spectrum of the bursting atoll source 4U 1728-34 observed
with INTEGRAL.
Falanga M., Goetz D., Goldoni P., Farinelli R., Goldwurm A., Mereghetti S.,
Bazzano A., Stella L.
<Astron. Astrophys. 458, 21 (2006)>
=2006A&A...458...21F 2006A&A...458...21F
ADC_Keywords: X-ray sources ; Gamma rays
Keywords: binaries: close - stars: pulsars: individual: 4U 1728-34 -
stars: neutron - X-rays: bursts
Abstract:
We present for the first time a study of the 3-200keV broad band
spectra of the bursting atoll source 4U 1728-34 (GX 354-0) along its
hardness intensity diagram. The analysis was done using the INTEGRAL
public and Galactic Center deep exposure data ranging from February
2003 to October 2004.
Objects:
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RA (2000) DE Designation(s)
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17 31 57.4 -33 50 05 4U 1728-34 = GX 354-00
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 85 36 Log of INTEGRAL burst observations analyzed in
this paper and spectral properties of the bursts
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See also:
J/A+A/411/L59 : INTEGRAL reference catalog (Ebisawa+, 2003)
J/A+A/438/1175 : First INTEGRAL SPI-ACS Gamma-Ray Burst Catalogue (Rau+, 2005)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Burst Burst number
3 A1 --- n_Burst [+] +: bright type I X-ray bursts
6- 15 A10 "YYYY/MM/DD" Date IBIS/JEMX date
17- 24 A8 "h:m:s" Tstart IBIS/JEM-X starting time, in hh:mm:ss
26- 29 F4.1 s DTburst ?=- IBIS time interval of the burst (1)
31- 32 F2.1 s e_DTburst ? rms uncertainty on DTburst
34- 37 F4.2 s tauexp ?=- JEMX burst exponential decay time, in
the 3-20keV energy band
39- 40 F2.1 s e_tauexp ? rms uncertainty on tauexp
42- 45 F4.1 kg/cm2/s dm/dt ?=- Mass accretion rate per unit area of the
persistent emission before the bursts (2)
47- 48 F2.1 kg/cm2/s e_dm/dt ? rms uncertainty on dm/dt
50- 52 F3.1 10-10J/m2 Eb ?=- Net burst fluence, persistent emission
subtracted (in 10-7erg/cm-2)
54- 55 F2.1 10-10J/m2 e_Eb ? rms uncertainty on Eb
57- 59 F3.1 10-11W/m2 Fpeak ?=- Net burst peak flux, persistent emission
subtracted (in 10-8erg/cm2/s)
61- 62 F2.1 10-11W/m2 e_Fpeak ? rms uncertainty on Fpeak
64- 66 F3.1 s tau ?=- Burst parameter tau=Eb/Fpeak
68- 69 F2.1 s e_tau ? rms uncertainty on tau
71- 75 F5.3 --- gamma ?=- Burst parameter gamma=Fpers/Fpeak
77- 80 F4.3 --- e_gamma ? rms uncertainty on gamma
82 A1 --- l_alpha [~] Limit flag on alpha
83- 85 I3 --- alpha ?=- Burst parameter alpha (3)
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Note (1): "---" means not a statistically significant detection in ISGRI.
Note (2): Assuming a canonical neutron star radius of 10km.
Note (3): The quantity alpha is defined as the ratio of the total energy
emitted in the persistent flux to that emitted in bursts,
alpha=Fpers*Δt/Eb,
where Δt is the time interval from the beginning of one
burst to the next. We report only the most confident alpha values,
i.e. without data gap between two bursts.
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Acknowledgements: Maurizio Falanga, mfalanga(at)cea.fr
(End) Patricia Vannier [CDS] 09-Oct-2006