MOJAVE
(
Monitoring
Of
Jets
in
Active galactic nuclei with
VLBA
Experiments)
is a long-term
program to monitor radio brightness and polarization variations in jets
associated with active galaxies visible in the northern sky.
Approximately 2/3 of these were observed from 1994-2002 as part of
the
VLBA 2 cm Survey.
These jets are powered by the accretion of material onto
billion-solar-mass black holes located in the nuclei of active
galaxies. Their
rapid brightness variations and
apparent
superluminal motions indicate
that they contain highly energetic plasma moving nearly directly at us
at speeds approaching that of light. Our observations
are made with the world's highest resolution telescope: the
Very Long
Baseline
Array (VLBA) at a wavelength of 2 cm, which enables us to make full
polarization images with an angular resolution
better than 1
milliarcsecond (the apparent separation of your car's headlights parked
on the Moon, as seen from Earth). We are using these data to better
understand the
complex evolution and magnetic field structures of these jets on
light-year
scales, close to where they originate in the active nucleus.
For astronomers:
All calibrated (u,v) visibility and FITS data for the MOJAVE and 2 cm
Survey programs are available via html links on the
source pages. If you are interested in
Stokes Q,U,V (linear and circular polarization) FITS images, please
contact us.
If
you intend to use these data in a
publication, we ask that you please contact us so we can add a link to
our external publications page, and that you include the following
acknowledgment: "This research has made use of data from the MOJAVE
database that is maintained by the MOJAVE team (Lister et al., 2009,
AJ, 137, 3718)"
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WHAT'S NEW:
New composite Fermi-VLBA Image:

We have released a
new composite image showing
the gamma-ray sky based on the first 3 months of Fermi data, with
zoomed-in VLBA images of bright extragalactic jets from the MOJAVE
program. Three papers on joint Fermi-MOJAVE VLBA results have
been accepted for publication:
Lister et al. 2009,
Kovalev et al. 2009, and
Abdo et al. 2009.
Image paper in AJ: A
paper containing all 2 cm VLBA images of the MOJAVE flux-limited AGN
sample from our program and the VLBA archive is now published in the
Astronomical Journal. This paper also contains
'stacked' naturally weighted and uniformly weighted images, which are
the average of all the available 2 cm VLBA images on that
particular source.
Addition of 2 AGN to
complete MOJAVE sample: In processing archival VLBA data, we
have found two additional AGN that satisfied the flux-limited MOJAVE
sample criteria during the period 1994-2003. These two sources
(0838+133 and 1807+698) have been added to the flux-limited sample,
bringing the total up to 135 sources.
MOJAVE in the Fermi
Era: Regular VLBA observations of the MOJAVE sample
have been approved by NRAO to continue through June 2010. These are
being
carried out at the approximate rate of 30 AGN every 3 weeks at 2 cm
wavelength. Each AGN is observed every 1 to 24 months,
depending on its rate of angular evolution on the sky and jet activity level. The
current list of sources being monitored can be found in our
information table.
Up to 100 additional Fermi LAT-detected
gamma-ray AGN that have correlated 2 cm VLBA flux exceeding ~100 mJy
are being added to the sample. The current sample includes:
- all currently known EGRET gamma-ray AGN above
declination -20°
- 33 low-luminosity AGN (15 GHz luminosity < 1026
W/Hz)
- 6 gigahertz-peaked spectrum sources
- 11 AGN from the previous 2cm Survey that have
unusual kinematics.
Movies: On
our
movies page you can click
on the name of an active galaxy and get a MPEG movie showing its total
intensity and linearly polarized jet evolution over the several years.
Clicking
on a thumbnail image will display a movie showing the total intensity
evolution in the jet over the last twelve years (or a shorter time
interval, depending on available data). Note that some movies contain
blank frames due to missing temporal coverage - if you have published 2
cm VLBA data on any AGN
listed on this web site and wish to contribute them to our online
archive,
please let us know!
Kinematics Plots: Plots
are now available for selected
jets in
the MOJAVE survey showing the separation of individual jet
features with respect to the (presumed stationary) core feature as a
function of time. These are subject to change as we add new epochs.
MOJAVE Multifrequency Observations:
During 2006 (BL137), a single multi-frequency VLBA epoch at 8.1, 8.4, 12.1
and 15.3 GHz was obtained for all sources in the MOJAVE sample. These
are currently being reduced, and are being used to explore the
properties
of
intervening gas responsible for modifying the observed polarization of
the jet emission.
Superluminal Motion Demonstration Applet: REU student Quinn Looker and Prof. Matthew Lister of Purdue University have developed a
Flash software applet to
demonstrate the principle of superluminal motion.