REVIEW 6 cited by
Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
read the original abstract
The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds the critical value, known as the Eddington limit. Discovery of ultraluminous X-ray sources has shown that accretion can proceed even when the apparent luminosity significantly exceeds this limit. High apparent luminosity might be produced thanks to geometric beaming of the radiation by an outflow. The outflow half-opening angle, which determines the amplification due to beaming, has never been robustly constrained. Using the Imaging X-ray Polarimetry Explorer, we made the measurement of X-ray polarization in the Galactic X-ray binary Cyg X-3. We find high, over 20%, nearly energy-independent linear polarization, orthogonal to the direction of the radio ejections. These properties unambiguously indicate the presence of a collimating outflow in the X-ray binary Cyg~X-3 and constrain its half-opening angle, <15 degrees. Thus, the source can be used as a laboratory for studying the super-critical accretion regime. This finding underscores the importance of X-ray polarimetry in advancing our understanding of accreting sources.
Forward citations
Cited by 6 Pith papers
-
Cygnus X-3: A variable petaelectronvolt gamma-ray source
Cygnus X-3 produces variable gamma rays up to 3.7 PeV, consistent with photomeson production in its relativistic jet requiring protons accelerated to tens of PeV.
-
Peering through the dip: IXPE unveils the extended scattering environment of GX 13+1
During the periodic dip of GX 13+1, X-ray polarization rises to 9.1%±1.1% and rotates by ~60° relative to the off-dip state, consistent with scattering in an oblate corona or disk wind.
-
Unchanged X-Ray Polarization During Accretion Dips in the Low Hard State of Cygnus X-1
During Cygnus X-1 accretion dips the 2–8 keV polarization is unchanged within errors, indicating the absorbed disk does not contribute and supporting an extended oblate corona.
-
Proof of Concept Measurements of Laterally Graded Multilayers for Soft X-ray Spectropolarimetry
Cr/Sc and W/B4C laterally graded multilayer mirrors modulate soft X-ray reflection with polarization angle, showing ~100% modulation at Brewster angle and ~80% at 30° incidence.
-
Astrophysical X-Ray Polarization
Reviews mechanisms generating polarized X-rays in high-energy astrophysics and the detectors for measuring polarization fraction and angle.
-
Imaging X-ray Polarimetry Explorer
IXPE, launched in December 2021, is the first dedicated imaging X-ray polarimetry observatory and has measured X-ray polarization for about 110 cosmic sources.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.