BU022

NGC 4151: Where is the nucleus, and how fast is the jet?

Abstract

We propose seven epochs of 3.6-cm VLBA-only imaging of the Seyfert galaxy NGC 4151, with approximately two months between epochs, as well as a single epoch at 2 (mostly) and 6 cm using the VLBA, Y27, GBT, and Effelsberg. Among the Seyfert galaxies resolved by the VLBA at sub-parsec resolution, NGC 4151 is unique in having a resolved, linear radio source that appears to be a small-scale jet. Two previous 6-cm observations were separated by 22 months and had limited (u,v) coverage; they showed structural changes, but it was not possible to identify components or measure speeds between the epochs. The proposed multi-epoch 3.6-cm observations will provide sensitivity to jet speeds from 0.1c to at least 3c. The single epoch of multi-frequency observations using very sensitive telescopes will provide the capability to identify the exact location of the active nucleus among the several radio components which will be used in the kinematic modeling of the jet.

**Investigators**
Name	Other *	Institution	Email	Phone
James Ulvestad	PI	NRAO
Tony Wong	S	Cornell University
Greg Taylor		NRAO - Socorro
Carole Mundell		Astrophysics Research Institut	cgm@astro.livjm.ac.uk	44-151-231-2917

* PI = Principal Investigator; T = Thesis observations; S = Student

Front Ends

Gregorian C(3.95 to 5.85 GHz)
Gregorian X(8.2 to 10.0 GHz)
Gregorian Ku  U(12.4 to 15.4 GHz)

Back Ends

VLBA recorder and DAR

Type of Observing

Very Long Baseline Interferometry

Switching Type

Allocated time: 12.00 hours.

Previous proposal
Next proposal
Return to Trimester list