Dense Iron Ejecta and Core-collapse Supernova Explosion in the Young Supernova Remnant G11.2-0.3

Abstract

We present the results of near-infrared spectroscopic observations of dense ($\simgt$ 10${}^3$ cm${}^{-3}$) iron ejecta in the young core-collapse supernova remnant G11.2-0.3. Five ejecta knots projected to be close to its center show a large dispersion in their Doppler shifts: two knots in the east are blueshifted by more than 1,000 \kms, while three western knots have relatively small blueshifts of 20-60 \kms. This velocity discrepancy may indicate that the western knots have been significantly decelerated or that there exists a systematic velocity difference among the knots. One ejecta filament in the northwestern boundary, on the other hand, is redshifted by $\simgt$ 200 \kms, while opposite filament in the southeastern boundary shows a negligible radial motion. Some of the knots and filaments have secondary velocity components, and one knot shows a bow shock-like feature in the velocity structure. The iron ejecta appear to be devoid of strong emission from other heavy elements, such as S, which may attest to the alpha-rich freezeout process in the explosive nucleosynthesis of the core-collapse supernova explosion close to its center. The prominent bipolar distribution of the Fe ejecta in the northwestern and southeastern direction, along with the elongation of the central pulsar wind nebula in the perpendicular direction, is consistent with the interpretation that the supernova exploded primarily along the northwestern and southeastern direction.

To appear in ApJ Letters

References in corpus (4)

• The Expansion Asymmetry and Age of the Cassiopeia A Supernova Remnant
• A non-spherical core in the explosion of supernova SN 2004dj
• [Fe II] and H2 filaments in the Supernova Remnant G11.2-0.3: Supernova Ejecta and Presupernova Circumstellar Wind
• The Shape of Cas A

Cited by in corpus (15)

• Three-dimensional neutrino-driven supernovae: Neutron star kicks, spins, and asymmetric ejection of nucleosynthesis products
• The Mipsgal View of Supernova Remnants in the Galactic Plane
• A Catalogue of Galactic Supernova Remnants in the far-infrared: revealing ejecta dust in pulsar wind nebulae
• G11.2-0.3: The Young Remnant of a Stripped-Envelope Supernova
• The observed mass distribution of Galactic black hole LMXBs is biased against massive black holes
• Near-infrared [Fe II] and H${}_2$ Emission-line Study of Galactic Supernova Remnants in the First Quadrant
• UKIRT Widefield Infrared Survey for Fe${}^{+}$
• AKARI Infrared Observations of the Supernova Remnant G292.0+1.8: Unveiling Circumstellar Medium and Supernova Ejecta
• Near-Infrared Knots and Dense Fe Ejecta in the Cassiopeia A Supernova Remnant
• Far-Infrared Luminous Supernova Remnant Kes 17
• Near-Infrared Spectroscopy of Infrared-Excess Stellar Objects in the Young Supernova Remnant G54.1+0.3
• Near-Infrared Spectroscopy of Young Galactic Supernova Remnants
• Wide Integral-Field Infrared Spectroscopy of the Bright [Fe II] Shell in the Young Supernova Remnant G11.2-0.3
• Extended Ionized Fe Objects in the UWIFE Survey
• Infrared [Fe II] and Dust Emissions from Supernova Remnants