Skip to content
DraconiticResearch
Search Sources API
181,716 studies31 sourcesUpdated 30 min ago
Peer-reviewedCC BY 4.0The Astrophysical Journal Letters

IXPE Observation of the New Magnetar Source EP J223759.5+531421

  • Roberto Taverna1
  • Lorenzo Marra2
  • Roberto Turolla1,3
  • Ruth M. E. Kelly1,3
  • Silvia Zane3
  • Alice Borghese4
  • Francesco Coti Zelati5,6
  • Paolo Esposito7
  • Gian Luca Israel8
  • Nanda Rea5,6
  • Haonan Yang9
  • Yilong Wang5,6
9 affiliations
  1. 1University of Padova
  2. 2INAF—Istituto di Astrofisica e Planetologia Spaziali
  3. 3University College London
  4. 4European Space Agency (ESA)
  5. 5Institute of Space Sciences (ICE)
  6. 6Institut d’Estudis Espacials de Catalunya (IEEC)
  7. 7University School for Advanced Studies IUSS Pavia
  8. 8INAF - Osservatorio Astronomico di Roma
  9. 9Chinese Academy of Sciences
Open at sourcePDFDOICite

Abstract

We report on the detection of polarized X-ray emission from the new Galactic magnetar EP J223759.5+531421, discovered by the Einstein Probe Wide-field X-ray Telescope on 2026 June 28. The Imaging X-ray Polarimetry Explorer (IXPE) follow-up observation started on 2026 July 6 and detected the source at a (absorbed) flux of ≈4.5 × 10 ⁻¹¹ erg cm ⁻² s ⁻¹ (2–7.5 keV range), confirming the presence of two thermally emitting regions on the star surface, with temperatures ≈0.5 and ≈1 keV. A significant (at >4 σ confidence level) phase- and energy-integrated polarization degree of ≈7% was detected with the polarization angle ≈−2 ∘ East of the celestial North. The two thermal components exhibit quite different polarization properties. The difference is larger in the phase-folded data, with the polarization degree reaching ∼63% in the range 4–7.5 keV, in correspondence with the secondary peak of the pulse profile, and never exceeding ∼30% at lower energies. The polarization angle continuously oscillates from −90 ∘ to +90 ∘ over one rotational cycle and is well fit by the rotating vector model, with an inclination of the line of sight and of the magnetic dipole axis relative to the star spin axis of ≈28 ∘ and ≈109 ∘ , respectively. The data point to an emission geometry in which the warm thermal component could originate from two antipodal caps, possibly in a magnetically condensed state, while the hot one could come from a smaller region covered by an atmosphere.

Related

  1. Einstein Probe discovery of the magnetar EP J223759.5+531421
    N Rea, F Coti Zelati, A Borghese +44
    HALPreprintCC BY 4.0Full textHigh-energy astrophysicsGeneral physicsHALarXiv
  2. The Disk Awakens: IXPE's Sequel Observation of GS 1354-64 Suggests Changing-Look Behavior in the Steep-Power-Law State
    Swati Ravi, James F. Steiner, Megan Masterson +20
    arXivPreprintCC BY 4.0Full textHigh-energy astrophysicsarXiv
  3. The first IXPE view of the eclipsing ADC source 4U 1822-37
    A. Anitra, A. Gnarini, T. Di Salvo +16
    arXivPreprintarXiv licenceFull textHigh-energy astrophysicsarXiv
  4. SS 433 Eastern Jet Turbulence Revealed by Spatially-Resolved IXPE Data Analysis
    Ningyue Fan, Jack T. Dinsmore, Roger W. Romani
    arXivPreprintCC BY 4.0Full textHigh-energy astrophysicsarXiv
  5. In-orbit anomaly and recovery of IXPE detector 2
    Fabio Muleri, Luca Baldini, Sudip Chakraborty +18
    arXivPreprintCC BY-NC-ND 4.0Full textHigh-energy astrophysicsInstrumentation & methodsarXiv

Cite

BibTeXRIS
BibTeX
@article{taverna2026ixpe,
  title = {{IXPE Observation of the New Magnetar Source EP J223759.5+531421}},
  author = {Roberto Taverna and Lorenzo Marra and Roberto Turolla and Ruth M. E. Kelly and Silvia Zane and Alice Borghese and Francesco Coti Zelati and Paolo Esposito and Gian Luca Israel and Nanda Rea and Haonan Yang and Yilong Wang},
  journal = {The Astrophysical Journal Letters},
  year = {2026},
  month = nov,
  doi = {10.3847/2041-8213/aeb4aa},
  url = {https://iopscience.iop.org/article/10.3847/2041-8213/aeb4aa},
  note = {CC BY 4.0},
}
RIS
TY  - JOUR
TI  - IXPE Observation of the New Magnetar Source EP J223759.5+531421
AU  - Roberto Taverna
AU  - Lorenzo Marra
AU  - Roberto Turolla
AU  - Ruth M. E. Kelly
AU  - Silvia Zane
AU  - Alice Borghese
AU  - Francesco Coti Zelati
AU  - Paolo Esposito
AU  - Gian Luca Israel
AU  - Nanda Rea
AU  - Haonan Yang
AU  - Yilong Wang
PY  - 2026
DA  - 2026/11/02
JO  - The Astrophysical Journal Letters
DO  - 10.3847/2041-8213/aeb4aa
UR  - https://iopscience.iop.org/article/10.3847/2041-8213/aeb4aa
AB  - We report on the detection of polarized X-ray emission from the new Galactic magnetar EP J223759.5+531421, discovered by the Einstein Probe Wide-field X-ray Telescope on 2026 June 28. The Imaging X-ray Polarimetry Explorer (IXPE) follow-up observation started on 2026 July 6 and detected the source at a (absorbed) flux of ≈4.5 × 10 ⁻¹¹ erg cm ⁻² s ⁻¹ (2–7.5 keV range), confirming the presence of two thermally emitting regions on the star surface, with temperatures ≈0.5 and ≈1 keV. A significant (at >4 σ confidence level) phase- and energy-integrated polarization degree of ≈7% was detected with the polarization angle ≈−2 ∘ East of the celestial North. The two thermal components exhibit quite different polarization properties. The difference is larger in the phase-folded data, with the polarization degree reaching ∼63% in the range 4–7.5 keV, in correspondence with the secondary peak of the pulse profile, and never exceeding ∼30% at lower energies. The polarization angle continuously oscillates from −90 ∘ to +90 ∘ over one rotational cycle and is well fit by the rotating vector model, with an inclination of the line of sight and of the magnetic dipole axis relative to the star spin axis of ≈28 ∘ and ≈109 ∘ , respectively. The data point to an emission geometry in which the warm thermal component could originate from two antipodal caps, possibly in a magnetically condensed state, while the hot one could come from a smaller region covered by an atmosphere.
SN  - 2041-8213
SN  - 2041-8205
ER  -