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Article
Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds a critical value known as the Eddington limit. The discovery of ultraluminous X-ray sources has shown...
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Article
Complex rotational dynamics of the neutron star in Hercules X-1 revealed by X-ray polarization
In an accreting X-ray pulsar, a neutron star accretes matter from a companion star through an accretion disk. The magnetic field of the rotating neutron star disrupts the inner edge of the disk, funnelling the...
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Article
Discovery of X-ray polarization angle rotation in the jet from blazar Mrk 421
The magnetic-field conditions in astrophysical relativistic jets can be probed by multiwavelength polarimetry, which has been recently extended to X-rays. For example, one can track how the magnetic field chan...
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Article
X-ray polarization evidence for a 200-year-old flare of Sgr A*
The centre of the Milky Way Galaxy hosts a black hole with a solar mass of about 4 million (Sagittarius A* (Sgr A)) that is very quiescent at present with a luminosity many orders of magnitude below those of acti...
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Article
Simultaneous space and phase resolved X-ray polarimetry of the Crab pulsar and nebula
The Crab pulsar and its nebula are among the most studied astrophysical systems, and constitute one of the most promising environments where high-energy processes and particle acceleration can be investigated....
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Article
Determination of X-ray pulsar geometry with IXPE polarimetry
Using observations of X-ray pulsar Hercules X-1 by the Imaging X-ray Polarimetry Explorer we report a highly significant (>17σ) detection of the polarization signal from an accreting neutron star. The observed de...
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Article
Vela pulsar wind nebula X-rays are polarized to near the synchrotron limit
Pulsar wind nebulae are formed when outflows of relativistic electrons and positrons hit the surrounding supernova remnant or interstellar medium at a shock front. The Vela pulsar wind nebula is powered by a y...
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Article
Open AccessPolarized blazar X-rays imply particle acceleration in shocks
Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are ...
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Article
Open AccessA polarized view of the hot and violent universe
X-ray polarimetry has long been considered the ‘holy grail’ of X-ray astronomy. Fortunately, after a silence of more than 40 years, the field is now rejuvenating. In fact, an X-ray polarimeter onboard a Cube-s...
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Chapter
Optical Polarimetry: Methods, Instruments and Calibration Techniques
In this chapter we present a brief summary of methods, instruments and calibration techniques used in modern astronomical polarimetry in the optical wavelengths. We describe the properties of various polarisat...
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Article
Dense matter with eXTP
In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cann...
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Chapter
Modelling Spectral and Timing Properties of Accreting Black Holes: The Hybrid Hot Flow Paradigm
The general picture that emerged by the end of 1990s from a large set of optical and X-ray, spectral and timing data was that the X-rays are produced in the innermost hot part of the accretion flow, while the ...
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Article
Modelling Spectral and Timing Properties of Accreting Black Holes: The Hybrid Hot Flow Paradigm
The general picture that emerged by the end of 1990s from a large set of optical and X-ray, spectral and timing data was that the X-rays are produced in the innermost hot part of the accretion flow, while the ...
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Article
XIPE: the X-ray imaging polarimetry explorer
Abstract X-ray polarimetry, sometimes alone, and sometimes coupled to spectral and temporal variability measurements and to imaging, allows a wealth of physical phenomena in astrophysics ...
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Chapter and Conference Paper
Thermal Comptonization in GRS 1915+105
The Rossi X-ray Timing Explorer (RXTE) data of GRS 1915+105 from several observing periods were modelled with a thermal Comptonization model. In the model (Figure 1), seed soft photons from an optically thick coo...
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Article
Thermal Comptonization in GRS 1915+105
The Rossi X-ray Timing Explorer (RXTE) data of GRS 1915+105 from severalobserving periods were modelled with a thermal Comptonization model. Inthe model (Figure 1), seed soft photons from an optically thick co...
