Black Hole Jets
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Black Hole JetsAcceleration of jetsCollimation of jetsSuperluminal motionEvolution of jets
Jets| -- Size of our Galaxy -- |
Acceleration of a jet
Collimation of a jetProduction of jets is not well understood and is a major topic in current research.
What is the lifetime of this jet?| ------------------ | = 150,000 light years
Evolution of JetsJets from active galaxies are large and change slowly.Jets from solar-mass black holes are smaller, by the ratio of the black hole masses, and change more rapidly.It is possible to study the evolution of jets from solar-mass black hole.
Jets of XTE J1550-564Show movie then animation.
Jet decelerationFirst direct observation of gradual deceleration of BH jet. Approaching jet decelerates gradually. Receding jet brightens only after sharp deceleration.
Intermediate Mass Black HolesEddington limitBeamingNebula around a black hole
A black hole is observed at a luminosity of 3,000,000 solar luminosities. The black hole mass must beat least 100 solar massesless than 100 solar massesexactly 100 solar massesimpossible to determine
Black hole massesTwo types of black holesStellar mass black holes are up to 20 solar masses, formed in collapse of starsSupermassive black holes are 106-109 solar masses, found only in the nuclei of galaxies
Is there anything in between?
Starburst galaxy M82
Starburst galaxy M82 in X-raysGreen cross is center of galaxyBright X-ray source is 15,000,000 solar luminositiesFrom Eddington limit, looks like a 500 solar mass black hole
BeamingIs the source really as luminous as it looks or are the X-rays in a beam pointing towards us?
Nebula surrounding a BHX-rays from the BH ionize Helium in the nebula which causes the Helium to emit one particular spectral lineBy counting the number of photons in this spectral line of Helium, we can count the number of X-rays and find the true X-ray luminosity in all directions
Nebula around a black holeImage from slit-less spectrographHorizontal axis shows positionVertical axis shows combination of position and wavelength
Nebula around a black holeBlack hole is at least 750,000 solar luminosities.Mass is at least 25 solar masses.
Review QuestionsHow are jets accelerated?How are jets collimated?Do superluminal jets really move faster than the speed of light?Do the jets of stellar-mass black holes evolve faster or slower than the jets of supermassive black holes?Estimating the mass of a black from its observed flux depends on what assumption?