EurekaMag.com logo
+ Site Statistics
References:
52,725,316
Abstracts:
28,411,598
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Bipolar jets launched from accretion disks II Formation of symmetric and asymmetric jets and counter jets


Bipolar jets launched from accretion disks II Formation of symmetric and asymmetric jets and counter jets
We investigate the jet launching process from accretion disks extending ourrecent study (paper I) to a truly bipolar setup. We perform axisymmetric MHDsimulations of the disk-jet interaction on a computational domain covering bothhemispheres, in particular addressing the question of an intrinsicallyasymmetric origin of jet / counter jet systems. Treating both hemispheressimultaneously, we overcome the equatorial plane symmetry boundary conditionused in most previous studies which naturally fosters a symmetric evolution.For the magnetic diffusivity prescription we apply an alpha-parametrisation,considering both, globally models of diffusivity, and local models. We firstapprove the quality of our numerical setup by generating perfectly symmetricjets, lasting over a 1000s of dynamical time scales. We then disturb thehemispheric symmetry in the disk, and investigate the subsequent evolution ofthe outflow. The evolution first leads to a substantial disk warping withelectric currents intersecting the equatorial plane. We investigate two models,i) a disk with (initially) different thermal scale height in both hemispheres,and ii) a symmetric disk into which a local disturbance is injected in onehemisphere. In both cases the disk asymmetry results in asymmetric outflowswith mass fluxes differing by 10-20%. We find up to 30% difference in mass fluxbetween jet and counter jet for this setup, lasting over 1000s of dynamicaltime scales (i.e. lasting for the whole simulation). In summary, our resultssuggest that the jet asymmetries in protostellar and extragalactic jets canindeed be generated intrinsically and maintained over long time by diskasymmetries and the standard jet launching mechanism.


Accession: 036880972



Related references

Black Holes, Accretion Disks and Relativistic Jets in Active Galactic Nucleia. Annals of the New York Academy of Sciences 688: 311-320, 1993

Alignment of magnetized accretion disks and relativistic jets with spinning black holes. Science 339(6115): 49-52, 2012

Heat transfer from impinging slot jets of air. 1. Aerodynamic characteristics of free jets. Wood science and technology2(4): 237-249, 1978

VLBI observations of helical jets hints on the nature of radio-jets. 2013

Surface dilution of round negative buoyant jets a comparison with other jets. Water Science & Technology 14(4-5): 13-20, 1982

Heat transfer from impinging slot jets of air. Part 1: Aerodynamic characteristics of free jets. Wood Science and Technology 12(4): 237-249, 1978

Impinging wall jets are much smaller than free jets an in vitro color doppler study. Circulation 80(4 SUPPL 2): II570, 1989

Shape studies of quark jets versus gluon jets at s=10 GeV. Physical Review. D, Particles and Fields 46(11): 4822-4827, 1992

Quantitation of regurgitant jets with high pulse repetition sampling of proximal jets with color flow imaging. Circulation 78(4 PART 2): II610, 1988

HST/WFC3 Imaging of Protostellar Jets in Carina Fe II Emission Tracing Massive Jets from Intermediate Mass Protostars. 2013