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Title: HIGH-ENERGY X-RAYS FROM J174545.5-285829, THE CANNONBALL: A CANDIDATE PULSAR WIND NEBULA ASSOCIATED WITH Sgr A EAST

Abstract

We report the unambiguous detection of non-thermal X-ray emission up to 30 keV from the Cannonball, a few-arcsecond long diffuse X-ray feature near the Galactic Center, using the NuSTAR X-ray observatory. The Cannonball is a high-velocity (v {sub proj} ∼ 500 km s{sup –1}) pulsar candidate with a cometary pulsar wind nebula (PWN) located ∼2' north-east from Sgr A*, just outside the radio shell of the supernova remnant Sagittarius A (Sgr A) East. Its non-thermal X-ray spectrum, measured up to 30 keV, is well characterized by a Γ ∼ 1.6 power law, typical of a PWN, and has an X-ray luminosity of L(3-30 keV) = 1.3 × 10{sup 34} erg s{sup –1}. The spectral and spatial results derived from X-ray and radio data strongly suggest a runaway neutron star born in the Sgr A East supernova event. We do not find any pulsed signal from the Cannonball. The NuSTAR observations allow us to deduce the PWN magnetic field and show that it is consistent with the lower limit obtained from radio observations.

Authors:
; ; ; ;  [1];  [2];  [3]; ;  [4];  [5];  [6];  [7];  [8];  [9];  [10]
  1. Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States)
  2. Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
  3. Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, 306, Santiago 22 (Chile)
  4. Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States)
  5. DTU Space—National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark)
  6. Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States)
  7. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
  8. Columbia University, New York, NY 10027 (United States)
  9. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)
  10. NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
Publication Date:
OSTI Identifier:
22364113
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 778; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; COSMIC PHOTONS; DETECTION; KEV RANGE; LUMINOSITY; MAGNETIC FIELDS; MILKY WAY; NEBULAE; NEUTRON STARS; PULSARS; SUPERNOVA REMNANTS; VELOCITY; X RADIATION; X-RAY SPECTRA

Citation Formats

Nynka, Melania, Hailey, Charles J., Mori, Kaya, Gotthelf, Eric V., Zhang, Shuo, Baganoff, Frederick K., Bauer, Franz E., Boggs, Steven E., Craig, William W., Christensen, Finn E., Harrison, Fiona A., Hong, Jaesub, Perez, Kerstin M., Stern, Daniel, and Zhang, William W. HIGH-ENERGY X-RAYS FROM J174545.5-285829, THE CANNONBALL: A CANDIDATE PULSAR WIND NEBULA ASSOCIATED WITH Sgr A EAST. United States: N. p., 2013. Web. doi:10.1088/2041-8205/778/2/L31.
Nynka, Melania, Hailey, Charles J., Mori, Kaya, Gotthelf, Eric V., Zhang, Shuo, Baganoff, Frederick K., Bauer, Franz E., Boggs, Steven E., Craig, William W., Christensen, Finn E., Harrison, Fiona A., Hong, Jaesub, Perez, Kerstin M., Stern, Daniel, & Zhang, William W. HIGH-ENERGY X-RAYS FROM J174545.5-285829, THE CANNONBALL: A CANDIDATE PULSAR WIND NEBULA ASSOCIATED WITH Sgr A EAST. United States. doi:10.1088/2041-8205/778/2/L31.
Nynka, Melania, Hailey, Charles J., Mori, Kaya, Gotthelf, Eric V., Zhang, Shuo, Baganoff, Frederick K., Bauer, Franz E., Boggs, Steven E., Craig, William W., Christensen, Finn E., Harrison, Fiona A., Hong, Jaesub, Perez, Kerstin M., Stern, Daniel, and Zhang, William W. Sun . "HIGH-ENERGY X-RAYS FROM J174545.5-285829, THE CANNONBALL: A CANDIDATE PULSAR WIND NEBULA ASSOCIATED WITH Sgr A EAST". United States. doi:10.1088/2041-8205/778/2/L31.
@article{osti_22364113,
title = {HIGH-ENERGY X-RAYS FROM J174545.5-285829, THE CANNONBALL: A CANDIDATE PULSAR WIND NEBULA ASSOCIATED WITH Sgr A EAST},
author = {Nynka, Melania and Hailey, Charles J. and Mori, Kaya and Gotthelf, Eric V. and Zhang, Shuo and Baganoff, Frederick K. and Bauer, Franz E. and Boggs, Steven E. and Craig, William W. and Christensen, Finn E. and Harrison, Fiona A. and Hong, Jaesub and Perez, Kerstin M. and Stern, Daniel and Zhang, William W.},
abstractNote = {We report the unambiguous detection of non-thermal X-ray emission up to 30 keV from the Cannonball, a few-arcsecond long diffuse X-ray feature near the Galactic Center, using the NuSTAR X-ray observatory. The Cannonball is a high-velocity (v {sub proj} ∼ 500 km s{sup –1}) pulsar candidate with a cometary pulsar wind nebula (PWN) located ∼2' north-east from Sgr A*, just outside the radio shell of the supernova remnant Sagittarius A (Sgr A) East. Its non-thermal X-ray spectrum, measured up to 30 keV, is well characterized by a Γ ∼ 1.6 power law, typical of a PWN, and has an X-ray luminosity of L(3-30 keV) = 1.3 × 10{sup 34} erg s{sup –1}. The spectral and spatial results derived from X-ray and radio data strongly suggest a runaway neutron star born in the Sgr A East supernova event. We do not find any pulsed signal from the Cannonball. The NuSTAR observations allow us to deduce the PWN magnetic field and show that it is consistent with the lower limit obtained from radio observations.},
doi = {10.1088/2041-8205/778/2/L31},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 778,
place = {United States},
year = {Sun Dec 01 00:00:00 EST 2013},
month = {Sun Dec 01 00:00:00 EST 2013}
}
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