Letter | Published:

# Identification of the central compact object in the young supernova remnant 1E 0102.2–7219

## Abstract

Oxygen-rich young supernova remnants1 are valuable objects for probing the outcome of nucleosynthetic processes in massive stars, as well as the physics of supernova explosions. Observed within a few thousand years after the supernova explosion2, these systems contain fast-moving oxygen-rich and hydrogen-poor filaments visible at optical wavelengths: fragments of the progenitor’s interior expelled at a few thousand kilometres per second during the supernova explosion. Here we report the identification of the compact object in the supernova remnant 1E 0102.2–7219 in reprocessed Chandra X-ray Observatory data, enabled by the discovery of a ring-shaped structure visible primarily in optical recombination lines of Ne i and O i. The optical ring has a radius of (2.10 ± 0.35)″ ≡ (0.63 ± 0.11) pc, and is expanding at a velocity of $90. 5 - 30 + 40$ km s−1. It surrounds an X-ray point source with an intrinsic X-ray luminosity L i (1.2–2.0 keV) = (1.4 ± 0.2) × 1033 erg s−1. The energy distribution of the source indicates that this object is an isolated neutron star: a central compact object akin to those present in the Cas A3,4,5 and Pup A6 supernova remnants, and the first of its kind to be identified outside of our Galaxy.

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## Acknowledgements

We thank E. M. Schlegel for constructive comments. This research has made use of BRUTUS, a Python module to process data cubes from integral field spectrographs hosted at http://fpavogt.github.io/brutus/. For this analysis, BRUTUS relied on STATSMODEL39, MATPLOTLIB40, ASTROPY (a community-developed core Python package for astronomy)41, APLPY (an open-source plotting package for Python)42, and montage, funded by the National Science Foundation under Grant Number ACI-1440620 and previously funded by the National Aeronautics and Space Administration’s Earth Science Technology Office, Computation Technologies Project, under Cooperative Agreement Number NCC5-626 between NASA and the California Institute of Technology.

This research has also made use of DRIZZLEPAC, a product of the Space Telescope Science Institute, which is operated by AURA for NASA, of the ALADIN interactive sky atlas43, of SAOIMAGE DS944 developed by Smithsonian Astrophysical Observatory, of NASA’s Astrophysics Data System, and of the NASA/IPAC Extragalactic Database45, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. Some of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). STScI is operated by the Association of Universities for Research in Astronomy, under NASA contract NAS5-26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NNX09AF08G and by other grants and contracts.

I.R.S. was supported by Australian Research Council Grant FT160100028. P.G. acknowledges support from HST grant HST-GO-14359.011. A.J.R. has been funded by the Australian Research Council grant numbers CE110001020 (CAASTRO) and FT170100243. F.P.A.V. and I.R.S. thank the CAASTRO AI travel grant for generous support. P.G. thanks the Stromlo Distinguished Visitor Program. F.P.A.V. and E.S.B. are European Southern Observatory (ESO) Fellows. A.J.R. was affiliated, in part, with the ARC Centre for All-sky Astrophysics (CAASTRO).

This study is based on observations made with ESO Telescopes at the La Silla Paranal Observatory under program ID 297.D-5058.

## Author information

### Affiliations

1. #### European Southern Observatory, Vitacura, Santiago, Chile

• Frédéric P. A. Vogt
•  & Elizabeth S. Bartlett
2. #### School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Australian Defence Force Academy, Canberra, Australian Capital Territory, Australia

• Ivo R. Seitenzahl
•  & Ashley J. Ruiter
3. #### Research School of Astronomy and Astrophysics, Australian National University, Canberra, Australian Capital Territory, Australia

• Ivo R. Seitenzahl
• , Michael A. Dopita
•  & Ashley J. Ruiter
4. #### Department of Physics, Astronomy and Geosciences, Towson University, Towson, MD, USA

• Parviz Ghavamian
5. #### Department of Physics and Astronomy, University of Georgia, Athens, GA, USA

• Jason P. Terry

### Contributions

F.P.A.V. reduced and lead the analysis of the MUSE datacube. E.S.B. lead the spectral analysis of the Chandra dataset. All authors contributed to the interpretation of the observations, and the writing of the manuscript.

### Competing interests

The authors declare no competing interests.

### Corresponding author

Correspondence to Frédéric P. A. Vogt.

## Supplementary information

1. ### Supplementary Information

Supplementary Figures 1–6, Supplementary Tables 1–5