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View article: Investigating the mysterious nature of 1LHAASO J1740+0948u through deep <i>XMM-Newton</i> observations
Investigating the mysterious nature of 1LHAASO J1740+0948u through deep <i>XMM-Newton</i> observations Open
Context. 1LHAASO J1740+0948u is a very-high-energy (VHE) source initially reported in the first catalogue by the LHAASO Collaboration, with no previous identifications and no counterpart at other wavelengths. It is detected by the KM2A ins…
View article: Recasting the nature of INTEGRAL hard X-ray transients previously classified as active galactic nuclei
Recasting the nature of INTEGRAL hard X-ray transients previously classified as active galactic nuclei Open
We present new broad-band X-ray results aimed at the identification and characterization of four poorly studied hard X-ray transients discovered by INTEGRAL: IGR J16426+6536, IGR J09446-2636, IGR J21268+6203, and IGR J02447+7046. The key p…
View article: Low-frequency spectra of neutron star + OB supergiant binaries: Does wind density drive persistent and flaring modes of accretion?
Low-frequency spectra of neutron star + OB supergiant binaries: Does wind density drive persistent and flaring modes of accretion? Open
Neutron star high-mass X-ray binaries are well studied in wavebands between the infrared and hard X-rays. Their low-frequency millimeter and radio properties, on the other hand, remain poorly understood. We present observations of the mill…
View article: Unveiling the short and faint X-ray transient nature of IGR J17419–2802
Unveiling the short and faint X-ray transient nature of IGR J17419–2802 Open
We report new X-ray results from the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), Swift , Chandra , and XMM–Newton observations of the hitherto poorly studied unidentified X-ray transient IGR J17419−2802. We studied in detai…
View article: Unveiling the short and faint X-ray transient nature of IGR J17419-2802
Unveiling the short and faint X-ray transient nature of IGR J17419-2802 Open
We report new X-ray results from the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), Swift, Chandra, and XMM-Newton observations of the hitherto poorly studied unidentified X-ray transient IGR J17419-2802. We studied in detail …
View article: Probing the nature of the X-ray source IGR J16327-4940 with Chandra
Probing the nature of the X-ray source IGR J16327-4940 with Chandra Open
We report on the results of a Chandra observation of the source IGRJ16327-4940, suggested to be a high mass X-ray binary hosting a luminous blue variable star (LBV). The source field was imaged by ACIS-I in 2023 to search for X-ray emissio…
View article: XTE J1906+090: a persistent low-luminosity Be X-ray binary
XTE J1906+090: a persistent low-luminosity Be X-ray binary Open
We present new results from INTEGRAL and Swift observations of the hitherto poorly studied and unidentified X-ray source XTE J1906+090. A bright hard X-ray outburst (luminosity of ∼1036 erg s−1 above 20 keV) has been discovered with INTEGR…
View article: XTE J1906+090: a persistent low luminosity Be X-ray Binary
XTE J1906+090: a persistent low luminosity Be X-ray Binary Open
We present new results from INTEGRAL and Swift observations of the hitherto poorly studied and unidentified X-ray source XTE J1906+090. A bright hard X-ray outburst (luminosity of $\sim$10$^{36}$ erg s$^{-1}$ above 20 keV) has been discove…
View article: Capturing the lowest luminosity state of the supergiant fast X-ray transient XTE J1739−302
Capturing the lowest luminosity state of the supergiant fast X-ray transient XTE J1739−302 Open
Here, we report the results of our analysis of recent Chandra , XMM-Newton , and NuSTAR observations of the supergiant fast X-ray transient XTE J1739−302. The source was caught in a low X-ray luminosity state, from a few 10 31 –10 34 erg s…
View article: Capturing the lowest luminosity state of the Supergiant Fast X-ray Transient XTE J1739-302
Capturing the lowest luminosity state of the Supergiant Fast X-ray Transient XTE J1739-302 Open
We report here on the results of the analysis of Chandra, XMM-Newton and NuSTAR recent observations of the Supergiant Fast X-ray Transient XTEJ1739-302. The source was caught in a low X-ray luminosity state, from a few $10^{31}$ to $10^{34…
View article: <i>XMM</i>–<i>Newton</i> discovery of very high obscuration in the candidate supergiant fast X-ray transient AX J1714.1−3912
<i>XMM</i>–<i>Newton</i> discovery of very high obscuration in the candidate supergiant fast X-ray transient AX J1714.1−3912 Open
We have analysed an archival XMM–Newton EPIC observation that serendipitously covered the sky position of a variable X-ray source AX J1714.1−3912, previously suggested to be a supergiant fast X-ray transient (SFXT). During the XMM–Newton o…
View article: INTEGRAL View of TeV Sources: A Legacy for the CTA Project
INTEGRAL View of TeV Sources: A Legacy for the CTA Project Open
Investigations that were carried out over the last two decades with novel and more sensitive instrumentation have dramatically improved our knowledge of the more violent physical processes taking place in galactic and extra-galactic Black-…
View article: INTEGRAL View of TeV Sources: A Legacy for the CTA Project
INTEGRAL View of TeV Sources: A Legacy for the CTA Project Open
Investigations that were carried out over the last two decades with novel and more sensitive instrumentation have dramatically improved our knowledge of the more violent physical processes taking place in galactic and extra-galactic Black-…
View article: Chasing candidate Supergiant Fast X-ray Transients in the 1000 orbits <i>INTEGRAL</i>/IBIS catalogue
Chasing candidate Supergiant Fast X-ray Transients in the 1000 orbits <i>INTEGRAL</i>/IBIS catalogue Open
We report results from an investigation at hard X-rays (above 18 keV) and soft X-rays (below 10 keV) of a sample of X-ray transients located on the Galactic plane and detected with the bursticity method, as reported in the latest 1000 orbi…
View article: <i>XMM–Newton</i> and<i>INTEGRAL</i>analysis of the Supergiant Fast X-ray Transient IGR J17354−3255
<i>XMM–Newton</i> and<i>INTEGRAL</i>analysis of the Supergiant Fast X-ray Transient IGR J17354−3255 Open
We present the results of combined INTEGRAL and XMM-Newton observations of\nthe supergiant fast X-ray transient (SFXT) IGR J17354$-$3255. Three XMM-Newton\nobservations of lengths 33.4 ks, 32.5 ks and 21.9 ks were undertaken, the first\nan…
View article: First hard X-ray detection and broad-band X-ray study of the unidentified transient AX J1949.8+2534
First hard X-ray detection and broad-band X-ray study of the unidentified transient AX J1949.8+2534 Open
We present the results from INTEGRAL and Swift/XRT observations of the\nhitherto poorly studied unidentified X-ray transient AX J1949.8+2534, and on\narchival multiwavelength observations of field objects. Bright hard X-ray\noutbursts have…
View article: Investigating the X-ray counterparts to unidentified sources in the 1000-orbit INTEGRAL/IBIS catalogue
Investigating the X-ray counterparts to unidentified sources in the 1000-orbit INTEGRAL/IBIS catalogue Open
The latest INTEGRAL/IBIS all-sky survey lists 219 hard X-ray sources whose\nnature is still unknown. We report on our ongoing campaign aimed at identifying\nthese high-energy emitters by exploiting the focusing capabilities of the X-ray\nT…
View article: THE XMM-NEWTON AND INTEGRAL OBSERVATIONS OF THE SUPERGIANT FAST X-RAY TRANSIENT IGR J16328-4726<sup>∗</sup>†
THE XMM-NEWTON AND INTEGRAL OBSERVATIONS OF THE SUPERGIANT FAST X-RAY TRANSIENT IGR J16328-4726<sup>∗</sup>† Open
The accretion mechanism producing the short flares observed from the Supergiant Fast X-ray Transients (SFXT) is still highly debated and forms a major part in our attempts to place these X-ray binaries in the wider context of the High Mass…
View article: Discovery of two new fast X-ray transients with<i>INTEGRAL</i>: IGR J03346+4414 and IGR J20344+3913
Discovery of two new fast X-ray transients with<i>INTEGRAL</i>: IGR J03346+4414 and IGR J20344+3913 Open
We report on the discovery of two fast X-ray transients (FXTs) from analysis of archival INTEGRAL data. Both are characterized by a remarkable hard X-ray activity above 20?keV, in terms of duration (?15 and 30 min, respectively), peak flux…
View article: Spectral variation in the supergiant fast X-ray transient SAX J1818.6−1703 observed by<i>XMM–Newton</i>and<i>INTEGRAL</i>
Spectral variation in the supergiant fast X-ray transient SAX J1818.6−1703 observed by<i>XMM–Newton</i>and<i>INTEGRAL</i> Open
We present the results of a 30 ks XMM–Newton observation of the supergiant fast X-ray transient (SFXT) SAX J1818.6−1703 – the first in-depth soft X-ray study of this source around periastron. INTEGRAL observations shortly before and after …