IGR J11014-6103: Runaway Pulsar Firing an Extraordinary
Jet
An extraordinary jet trailing behind a runaway pulsar is seen in
this composite image that contains data from NASA's Chandra X-ray Observatory
(purple), radio
data from the Australia Compact Telescope Array (green), and optical data
from the 2MASS survey (red, green, and blue). The pulsar - a spinning neutron star -
and its tail are found in the lower right of this image. The tail stretches for
37 light years , making it the longest jet ever seen from an object in the Milky
Way galaxy, as described in our press
release.
The pulsar, originally discovered by ESA's INTEGRAL satellite, is called IGR
J1104-6103 and is moving away from the center of the supernova
remnant where it was born at a speed between 2.5 million and 5 million miles
per hour. This supersonic pace makes IGR J1104-6103 one of the fastest moving
pulsars ever observed.
A massive star ran out of fuel and collapsed to form the pulsar along with
the supernova remnant, the debris field seen as the large purple structure in
the upper left of the image. The supernova remnant (known as SNR MSH 11-61A) is
elongated along the top-right to bottom left direction, roughly in line with the
tail's direction. These features and the high speed of the pulsar suggest that
jets could have played an important role in the supernova explosion that formed
IGR J1104-6103.
In addition to its exceptional length, the tail behind IGR J1104-6103 has
other interesting characteristics. For example, there is a distinct corkscrew
pattern in the jet. This pattern suggests that the pulsar is wobbling like a top
as it spins, while shooting off the jet of particles.
Another interesting feature of this image is a structure called a pulsar wind
nebula (PWN), a cocoon of high-energy particles that enshrouds the pulsar and
produces a comet-like tail behind it. Astronomers had seen the PWN in
previous observations, but the new Chandra and ATCA data show that the PWN is
almost perpendicular to the direction of the jet. This is intriguing because
usually the pulsar's direction of motion, its jet, and its PWN are aligned with
one another.
One possibility requires an extremely fast rotation speed for the iron core
of the star that exploded as the supernova. A problem with this scenario is that
such fast speeds are not commonly expected to be achievable.
A paper, led by Lucia Pavan of the University of Geneva in Switzerland,
describing these results appears in the February 18th issue of the journal
Astronomy & Astrophysics and is also available online. Other
authors include Pol Bordas (University of Tuebingen in Germany), Gerd Puehlhofer
(Univ. of Tuebingen), Miroslav Filipovic (University of Western Sydney in
Australia), A. De Horta (Univ. of Western Sydney), A. O'Brien (Univ. of Western
Sydney), M. Balbo (Univ. of Geneva), R. Walter (Univ. of Geneva), E. Bozzo
(Univ. of Geneva), C. Ferrigno (Univ. of Geneva), E. Crawford (Univ. of Western
Sydney), and L. Stella (INAF).
Image credit: X-ray: NASA/CXC/ISDC/L.Pavan et al, Radio: CSIRO/ATNF/ATCA
Optical: 2MASS/UMass/IPAC-Caltech/NASA/NSF
NASA
Guillermo Gonzalo Sánchez Achutegui
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