On the Polar Caps of the Three Musketeers

By A. D. Luca, P. Caraveo, Sandro Mereghetti, M. Negroni, G. Bignami. 2004

139 citations recorded by the source corpus.

XMM-Newton EPIC observations of PSR B0656+14, PSR B1055-52, and Geminga have substantially increased the collection of statistics available for these three isolated neutron stars, so apparently similar to deserve the nickname of the Three Musketeers, given to them by Becker & Trümper. Here we take advantage of the EPIC statistics to perform phase-resolved spectroscopy for all three objects. The phase-averaged spectrum of the Three Musketeers is best described by a three-component model. This includes two blackbody components—a cooler one, possibly originating from the bulk of the star surface, and a hotter one, coming from a smaller portion of the star surface (a "hot spot")—plus a power law. The relative contributions of the three components are seen to vary as a function of phase, as the stars' rotation brings into view different emitting regions. The hot spots, which have very different apparent dimensions (in spite of the similarity of the three neutron stars polar cap radii) are responsible for the bulk of the phase variation. The amplitude of the observed phase modulation is also markedly different for the three sources. Another striking aspect of our phase-resolved phenomenology is the apparent lack of any common phase alignment between the observed modulation patterns for the two blackbody components. They are seen to vary in phase in the case of PSR B1055-52 but in antiphase in the case of PSR B0656+14. These findings do not support standard and simplistic models of neutron star magnetic field configuration and surface temperature distribution.

Subfields: Astronomy and Astrophysics, Geophysics

View Paper: https://www.semanticscholar.org/paper/ebf8cfb0530d252c293b4e4a1e91dfab8fbbe6ed

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. A. Harding
2. D. Lai
3. José A. Pons
4. W. Ho
5. C. Heinke
6. R. Perna
7. A. Beloborodov
8. A. Steiner

In Geophysics

1. José A. Pons
2. A. Beloborodov
3. W. Ho
4. D. Aguilera
5. A. Harding
6. A. Steiner
7. C. Heinke

Citations in the corpus

• Physics of strongly magnetized neutron stars (2006, background): “Phase-resolved spectroscopic observations are becoming possible, revealing the surface magnetic field geometry and emission radius of the pulsar (e.g. Caraveo et al (2004), De Luca et al (2005), Jackson and Halpern (2005)).”
• Unifying the observational diversity of isolated neutron stars via magneto-thermal evolution models. (2013, background): “…candidates since they have spectral information with poor statistics and/or a very uncertain age of the associated SNR. • Eight rotation powered pulsars, including the Vela pulsar and the so-called three Musketeers (PSR B0656, PSR B1055 and the γ-ray-loud, radio-quiet Geminga; De Luca et al. 2005).”
• The glitch-induced identity changes of PSR J1119−6127 (2010, background): “Pulsed X-rays have been observed for both PSR J1119–6127 (Gonzalez et al. 2005) and PSR B0656+14 (Córdova et al. 1989; De Luca et al. 2005).”
• Corona of Magnetars (2006, background): “Observations of X-ray emission from radio pulsars provide evidence for thermally emitting hotspots with an area that is consistent with the surface area of the magnetic poles (De Luca et al 2005).”
• Constraining the mass and radius of neutron stars in globular clusters (2017, background): “Many neutron stars show pulsations, implying the presence of hotter regions on their surface; examples include young pulsars (De Luca et al. 2005), old millisecond pulsars (Bogdanov 2013), young neutron stars without pulsar activity (Gotthelf et al. 2010), and accreting neutron stars (Patruno et…”