iván agudo with the collaboration of: s.n. molina, j. l. gómez (iaa-csic) t. p. krichbaum, a. roy,...

Iván AgudoIván Agudo

with the collaboration of:with the collaboration of:S.N. Molina, J. L. Gómez S.N. Molina, J. L. Gómez (IAA-CSIC)(IAA-CSIC)

T. P. Krichbaum, A. Roy, U. Bach T. P. Krichbaum, A. Roy, U. Bach (MPIfR)(MPIfR)I. Martí Vidal I. Martí Vidal (Chalmers)(Chalmers)

B. Campbell B. Campbell (JIVE)(JIVE)

Signs of internal rotation and helical Signs of internal rotation and helical magnetic field in the inner jet of NRAO 150magnetic field in the inner jet of NRAO 150

Introduction: NRAO 150

Agudo et al. (2007)

• Intense radio-mm source (~6Jy @86 GHz)

• Quasar at redshift z = 1.52 (Acosta-Pulido et al. 2010)

• Acompact + bright core plus a one-sided je up to 80 mas

• Misalignment by >100◦

• Suggests a bent structure of the inner jet oriented within a tiny angle to the line of sight

Signs of internal rotation and helical magnetic field in the inner jet of NRAO 150 Iván Agudo (JIVE), EVN Symposium 2014, Signs of internal rotation and helical magnetic field in the inner jet of NRAO 150 Iván Agudo (JIVE), EVN Symposium 2014, Cagliari (Italy), 07-10-2014Cagliari (Italy), 07-10-2014

Introduction New Data New Kinematic Scenario Toroidal-Like Magnetic Field Internal Jet Rotation 43 GHz Astrometry

Q2

• Jet expansion & fast counter-clock-wise rotation of the jet on the plane of the sky

• ~60º in 7yr ==> ~10º/yr

• Non radial superluminal speeds up to ~2.7c

Introduction: Jet wobbling in NRAO150

Agudo et al. (2007)

Total intensity VLBA NRAO150 images from 1997 to 2007 at 43 GHz.

Agudo et al. (2007)



Introduction: Jet wobbling in Other Blazars

Lister et al. (2013)

Agudo et al. (2012)



• “Jet wobbling”, is observed ONLY in the innermost regions of the jets.

• Causes must be related to properties of inner jet, accretion system, and SMBH

• Makes jet wobbling studies an interesting tool for jet formation/launching studies.

Introduction: Jet wobbling


• However, here is still no general paradigm to explain the phenomenon

Agudo (2009)

• Jet wobbling be triggered “in principle” by:• a) disk precession, b) erratic jet instabilities in rotating jets, c) orbital

motion


• “Jet wobbling”, is observed ONLY in the innermost regions of the jets.

• Causes must be related to properties of inner jet, accretion system, and SMBH

• Makes jet wobbling studies an interesting tool for jet formation/launching studies.

Introduction: Jet wobbling


• However, here is still no general paradigm to explain the phenomenon

Agudo (2009)

• Jet wobbling be triggered “in principle” by:• a) disk precession, b) erratic jet instabilities in rotating jets, c) orbital

motion


McKinney & Blandford (2009)


8 GHz 22 GHz 43 GHz15 GHz

NRAO150: New Data

Mol

ina

et a

l. (2

014)


NRAO150 - 86 GHz Global mm VLBI Array Data

2006-05-07 2008-05-08

2009-05-08 2010-05-06


43 GHz

NRAO150: New Data

Molina et al. (2014)Introduction New Data New Kinematic Scenario Toroidal-Like Magnetic Field Internal Jet Rotation 43 GHz Astrometry

• We confirm the counter clock-wise rotation of jet

• No sign of reversal of the sense of rotation

• Not possible to compute a period of jet wobbling, if anySigns of internal rotation and helical magnetic field in the inner jet of NRAO 150 Iván Agudo (JIVE), EVN Symposium 2014, Signs of internal rotation and helical magnetic field in the inner jet of NRAO 150 Iván Agudo (JIVE), EVN Symposium 2014,

Cagliari (Italy), 07-10-2014Cagliari (Italy), 07-10-2014

NRAO150: New Data • In Agudo et al. (2007), the

brighter jet feature (Q0) was assumed the stationary core

• New 22-43 spectral index maps do not support this (but do not rule out)

• Explore other kinematic scenarios not based on the assumption that a particular jet feature is stationary

Spectral index

22-43 GHz

Molina et al. (2014)


NRAO150: New Kinematic Scenario• New scenario based on internal rotation of the jet around an “a

priory” undetermined axis (removed assumption that Q0 is stationary)

• Jet feature trajectories assumed to be helical

• Assumption: we observe the cross section of the jet seen face-on when it rotates


Observer

Fitting Model

We solve for: ri

ini, ωi, vir, ϕi

ini

Chi square fitting

Molina et al. (2014)Introduction New Data New Kinematic Scenario Toroidal-Like Magnetic Field Internal Jet Rotation 43 GHz Astrometry

• Kinematic center not located at position of any particular jet emission feature


Modeled trajectories (r of all comps free)

Best fit parameters

NRAO150: New Kinematic Scenario

Compatible with previous kinematic scenario

Best Fit of Data Referenced back to Q0

Rotation of the jet features with regard to an undetermined jet point is a likely possibility

(absolute position was lost on self-calibration)



NRAO150: Signs of Toroidal Magnetic Field Configuration


Sticks: EVPA+90°


Linear polarization angle compatible with circular shape

Polarization compatible with toroidal magnetic field configuration


Linear polarization angle compatible with circular shape


Sticks: EVPA+90°



Polarization compatible with toroidal magnetic field configuration

NRAO150: Signs of Toroidal Magnetic Field Configuration


• No strong evidence of the present of a “classical” core

• New kinematic scenario compatible with jet features rotating around a fiducial point (not related to any jet feature)

• Polarization distribution compatible with toroidal magnetic field configuration

NRAO150: Internal Rotation of Jet Flow



McKinney & Blandford (2009)

3D GRMHD Simulations of jet formation

• No strong evidence of the present of a “classical” core

• New kinematic scenario compatible with jet features rotating around a fiducial point (not related to any jet feature)

• Polarization distribution compatible with toroidal magnetic field configuration

Porth et al. (2013)

3D RMHD Simulations of jet stabilityIf internal jet rotation and toroidal field really happen in NRAO150,

May be first time that are observed

NRAO150: Internal Rotation of Jet Flow


• Half of the new 43 GHz observations in phase-ref mode

• But did not provide conclusive results within accuracies ~ 50 μas

• Tracked emission feature (Q0) clusters

• Expected Q0 motion ~ 10 μas/yr

• Global (EVN + VLBA) 43 GHz phase-ref program approved to solve the ambiguity: (1)much longer time baseline > 10yr

(1)a factor ~4 more sensitive observations

Thanks for your attention!


NRAO150: 43 GHz Astrometric Study


iván agudo with the collaboration of: s.n. molina, j. l. gómez (iaa-csic) t. p. krichbaum, a. roy,...

Documents

inner jet of nrao

properties of inner

jet wobbling studies

helical magnetic field

jet formationlaunching

ivn agudo jive

period of jet wobbling

evn symposium