A broadband spectral analysis of 4U 1702-429 using XMM-Newton and Beppo SAX data

Tiziana Di Salvo, Rosario Iaria, Simonamichela Mazzola, Del Santo, Burderi, D'Amico, Riggio, Sanna, Segreto, Andrea Santangelo, Mazzola

Risultato della ricerca: Article

1 Citazione (Scopus)

Abstract

Context. Most of the X-ray binary systems containing neutron stars classified as Atoll sources show two different spectral states, referred to as soft and hard. Moreover, a large number of these systems show a reflection component relativistically smeared in their spectra, which provides information on the innermost region of the system. Aims. Our aim is to investigate the poorly studied broadband spectrum of the low-mass X-ray binary system 4U 1702-429, which was recently analysed combining XMM-Newton and INTEGRAL data. The peculiar value of the reflection fraction brought us to analyse further broadband spectra of 4U 1702-429. Methods. We re-analysed the spectrum of the XMM-Newton/INTEGRAL observation of 4U 1702-429 in the 0.3-60 keV energy range and we extracted three 0.1-100 keV spectra of the source analysing three observations collected with the BeppoSAX satellite. Results. We find that the XMM-Newton/INTEGRAL spectrum is well fitted using a model composed of a disc blackbody plus a Comptonised component and a smeared reflection component. We used the same spectral model for the BeppoSAX spectra, finding that the addition of a smeared reflection component is statistically significant. The best-fit values of the parameters are compatible to each other for the BeppoSAX spectra. We find that the reflection fraction is 0.05-0.01+0.3 for the XMM-Newton/INTEGRAL spectrum and between 0.15 and 0.4 for the BeppoSAX ones. Conclusions. The relative reflection fraction and the ionisation parameter are incompatible between the XMM-Newton/INTEGRAL and the BeppoSAX observations and the characteristics of the Comptonising corona suggest that the source was in a soft state in the former observation and in a hard state in the latter.
Lingua originaleEnglish
pagine (da-a)A89-
Numero di pagine10
RivistaASTRONOMY & ASTROPHYSICS
Volume621
Stato di pubblicazionePublished - 2019

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cita questo

A broadband spectral analysis of 4U 1702-429 using XMM-Newton and Beppo SAX data. / Di Salvo, Tiziana; Iaria, Rosario; Mazzola, Simonamichela; Del Santo; Burderi; D'Amico; Riggio; Sanna; Segreto; Santangelo, Andrea; Mazzola.

In: ASTRONOMY & ASTROPHYSICS, Vol. 621, 2019, pag. A89-.

Risultato della ricerca: Article

Di Salvo, T, Iaria, R, Mazzola, S, Del Santo, Burderi, D'Amico, Riggio, Sanna, Segreto, Santangelo, A & Mazzola 2019, 'A broadband spectral analysis of 4U 1702-429 using XMM-Newton and Beppo SAX data' ASTRONOMY & ASTROPHYSICS, vol. 621, pagg. A89-.
Di Salvo, Tiziana ; Iaria, Rosario ; Mazzola, Simonamichela ; Del Santo ; Burderi ; D'Amico ; Riggio ; Sanna ; Segreto ; Santangelo, Andrea ; Mazzola. / A broadband spectral analysis of 4U 1702-429 using XMM-Newton and Beppo SAX data. In: ASTRONOMY & ASTROPHYSICS. 2019 ; Vol. 621. pagg. A89-.
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title = "A broadband spectral analysis of 4U 1702-429 using XMM-Newton and Beppo SAX data",
abstract = "Context. Most of the X-ray binary systems containing neutron stars classified as Atoll sources show two different spectral states, referred to as soft and hard. Moreover, a large number of these systems show a reflection component relativistically smeared in their spectra, which provides information on the innermost region of the system. Aims. Our aim is to investigate the poorly studied broadband spectrum of the low-mass X-ray binary system 4U 1702-429, which was recently analysed combining XMM-Newton and INTEGRAL data. The peculiar value of the reflection fraction brought us to analyse further broadband spectra of 4U 1702-429. Methods. We re-analysed the spectrum of the XMM-Newton/INTEGRAL observation of 4U 1702-429 in the 0.3-60 keV energy range and we extracted three 0.1-100 keV spectra of the source analysing three observations collected with the BeppoSAX satellite. Results. We find that the XMM-Newton/INTEGRAL spectrum is well fitted using a model composed of a disc blackbody plus a Comptonised component and a smeared reflection component. We used the same spectral model for the BeppoSAX spectra, finding that the addition of a smeared reflection component is statistically significant. The best-fit values of the parameters are compatible to each other for the BeppoSAX spectra. We find that the reflection fraction is 0.05-0.01+0.3 for the XMM-Newton/INTEGRAL spectrum and between 0.15 and 0.4 for the BeppoSAX ones. Conclusions. The relative reflection fraction and the ionisation parameter are incompatible between the XMM-Newton/INTEGRAL and the BeppoSAX observations and the characteristics of the Comptonising corona suggest that the source was in a soft state in the former observation and in a hard state in the latter.",
keywords = "Accretion, accretion disks; Stars: Individual: 4U 1702-429; Stars: neutron; X-rays: Binaries; Astronomy and Astrophysics; Space and Planetary Science",
author = "{Di Salvo}, Tiziana and Rosario Iaria and Simonamichela Mazzola",
year = "2019",
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TY - JOUR

T1 - A broadband spectral analysis of 4U 1702-429 using XMM-Newton and Beppo SAX data

AU - Di Salvo, Tiziana

AU - Iaria, Rosario

AU - Mazzola, Simonamichela

AU - Del Santo, null

AU - Burderi, null

AU - D'Amico, null

AU - Riggio, null

AU - Sanna, null

AU - Segreto, null

AU - Santangelo, Andrea

AU - Mazzola, null

PY - 2019

Y1 - 2019

N2 - Context. Most of the X-ray binary systems containing neutron stars classified as Atoll sources show two different spectral states, referred to as soft and hard. Moreover, a large number of these systems show a reflection component relativistically smeared in their spectra, which provides information on the innermost region of the system. Aims. Our aim is to investigate the poorly studied broadband spectrum of the low-mass X-ray binary system 4U 1702-429, which was recently analysed combining XMM-Newton and INTEGRAL data. The peculiar value of the reflection fraction brought us to analyse further broadband spectra of 4U 1702-429. Methods. We re-analysed the spectrum of the XMM-Newton/INTEGRAL observation of 4U 1702-429 in the 0.3-60 keV energy range and we extracted three 0.1-100 keV spectra of the source analysing three observations collected with the BeppoSAX satellite. Results. We find that the XMM-Newton/INTEGRAL spectrum is well fitted using a model composed of a disc blackbody plus a Comptonised component and a smeared reflection component. We used the same spectral model for the BeppoSAX spectra, finding that the addition of a smeared reflection component is statistically significant. The best-fit values of the parameters are compatible to each other for the BeppoSAX spectra. We find that the reflection fraction is 0.05-0.01+0.3 for the XMM-Newton/INTEGRAL spectrum and between 0.15 and 0.4 for the BeppoSAX ones. Conclusions. The relative reflection fraction and the ionisation parameter are incompatible between the XMM-Newton/INTEGRAL and the BeppoSAX observations and the characteristics of the Comptonising corona suggest that the source was in a soft state in the former observation and in a hard state in the latter.

AB - Context. Most of the X-ray binary systems containing neutron stars classified as Atoll sources show two different spectral states, referred to as soft and hard. Moreover, a large number of these systems show a reflection component relativistically smeared in their spectra, which provides information on the innermost region of the system. Aims. Our aim is to investigate the poorly studied broadband spectrum of the low-mass X-ray binary system 4U 1702-429, which was recently analysed combining XMM-Newton and INTEGRAL data. The peculiar value of the reflection fraction brought us to analyse further broadband spectra of 4U 1702-429. Methods. We re-analysed the spectrum of the XMM-Newton/INTEGRAL observation of 4U 1702-429 in the 0.3-60 keV energy range and we extracted three 0.1-100 keV spectra of the source analysing three observations collected with the BeppoSAX satellite. Results. We find that the XMM-Newton/INTEGRAL spectrum is well fitted using a model composed of a disc blackbody plus a Comptonised component and a smeared reflection component. We used the same spectral model for the BeppoSAX spectra, finding that the addition of a smeared reflection component is statistically significant. The best-fit values of the parameters are compatible to each other for the BeppoSAX spectra. We find that the reflection fraction is 0.05-0.01+0.3 for the XMM-Newton/INTEGRAL spectrum and between 0.15 and 0.4 for the BeppoSAX ones. Conclusions. The relative reflection fraction and the ionisation parameter are incompatible between the XMM-Newton/INTEGRAL and the BeppoSAX observations and the characteristics of the Comptonising corona suggest that the source was in a soft state in the former observation and in a hard state in the latter.

KW - Accretion, accretion disks; Stars: Individual: 4U 1702-429; Stars: neutron; X-rays: Binaries; Astronomy and Astrophysics; Space and Planetary Science

UR - http://hdl.handle.net/10447/338143

UR - https://www.aanda.org/

M3 - Article

VL - 621

SP - A89-

JO - ASTRONOMY & ASTROPHYSICS

JF - ASTRONOMY & ASTROPHYSICS

SN - 0004-6361

ER -