A parseltongue pipeline A parseltongue pipeline for VLA analysis of for VLA analysis of

B1600+434B1600+434

Alicia Berciano Alba (JIVE/Kapteyn Institute)Alicia Berciano Alba (JIVE/Kapteyn Institute)Leon Koopmans (Kapteyn Institute)Leon Koopmans (Kapteyn Institute)

Mike Garrett (JIVE)Mike Garrett (JIVE)Olaf Wucknitz (JIVE) Olaf Wucknitz (JIVE)

Copenhagen, Nov 2006 Copenhagen, Nov 2006

Once upon a time… Strong Once upon a time… Strong LensingLensing

Effects related with anomalies in lens Effects related with anomalies in lens imagesimages

Wrong mass modelWrong mass model

Absorption by dustAbsorption by dust

Free-free absorption in the lens galaxy (e.g. B0218+357, Free-free absorption in the lens galaxy (e.g. B0218+357, Mittal thesis 2006Mittal thesis 2006))

Differential Scattering in the lens galaxy (e.g. 0128+437, Differential Scattering in the lens galaxy (e.g. 0128+437, Biggs et al. 2004Biggs et al. 2004))

Scintillation in our own galaxyScintillation in our own galaxy

Microlensing by starsMicrolensing by stars

CDM SubstructureCDM Substructure

Dwarf satellitesDwarf satellites

Small disks Small disks (M(Mööller et al. 2003)ller et al. 2003)

Clusters in the los Clusters in the los (Fassnach)(Fassnach)

CLASS CLASS B1600+434B1600+434

Lens: edge-on spiral galaxy at z = 0.41Lens: edge-on spiral galaxy at z = 0.41

Background source: QSO at z = 1.59Background source: QSO at z = 1.59 (Fassnacht & Cohen 1998)(Fassnacht & Cohen 1998)

2 images (flat spectrum radio sources)2 images (flat spectrum radio sources) A passes through the DM haloA passes through the DM halo B passes through the disk and bulgeB passes through the disk and bulge

BB

AA

(Koopmans et al 1998) (Koopmans et al 1998)

Why is B1600+434 interesting ?Why is B1600+434 interesting ?

Short-term variability in the difference Short-term variability in the difference lightcurve is bigger than the one expected lightcurve is bigger than the one expected from measurement errors from measurement errors First First unambiguous case of external variability in unambiguous case of external variability in a radio lens!!a radio lens!!

The light curve of image A shows The light curve of image A shows stronger variability than image Bstronger variability than image B

Current explanationCurrent explanation

Counterpart example:Counterpart example:

““Flat spectrum radio sources not affected by microlensing”Flat spectrum radio sources not affected by microlensing”

Neal Jackson, beginning of this sessionNeal Jackson, beginning of this session

static core static core + +

superluminal jetsuperluminal jet

doopler doopler boostingboosting

smaller smaller angular sizesangular sizes

Source =Source =

Why does image B not show microlensing?

(Patnaik & Kemball 2001)

Scatter-broadening in disk?(Koopmans & de Bruyn 2000)

INDEED!

BB

AA

But Microlensing or Scintillation?But Microlensing or Scintillation?

The way to quantitatively The way to quantitatively distinguish between distinguish between microlensing and scintillation microlensing and scintillation is their opposite behaviour is their opposite behaviour with frequencywith frequency

WE NEED MULTI-FREQUENCY OBSERVATIONS!!WE NEED MULTI-FREQUENCY OBSERVATIONS!!

(Koopmans & de Bruyn 2000)(Koopmans & de Bruyn 2000)

The DataThe Data

VLA radio continuum VLA radio continuum 361 epochs361 epochs 1 lens system + 4-5 flux calibrators1 lens system + 4-5 flux calibrators 13 Feb 1998 – 5 Jan 200313 Feb 1998 – 5 Jan 2003 Observed Bands: L, C, X, P, U, K Observed Bands: L, C, X, P, U, K VLA array config: A, B, AD, AB, BC, C, CDVLA array config: A, B, AD, AB, BC, C, CD

Automated data reductionAutomated data reduction

Run Files = classic AIPS scripting toolRun Files = classic AIPS scripting tool

ParselTongue = Python interface to classic AIPSParselTongue = Python interface to classic AIPS

And I have the experts at JIVE!!!And I have the experts at JIVE!!! Mark KettenisMark Kettenis Cormac ReinoldsCormac Reinolds James M. AndersonJames M. Anderson

Block Diagram of the Block Diagram of the pipelinepipeline

Flag phase calibrator

Self calibrationphase calibrator

Flag sources(lens + flux calibrators)

calibrate sources

Phaseself calibration

sources

Source modelfitting

Apply calibrationto Sources

Source Model

Source MapsSource Flux

First Test ResultsFirst Test Results

L-BAND FlaggingL-BAND Flagging

Before FlaggingBefore Flagging

After FlaggingAfter Flagging

L-BAND Preliminary MapsL-BAND Preliminary Maps

C-BAND FlaggingC-BAND Flagging

Before FlaggingBefore Flagging

After FlaggingAfter Flagging

C-BAND Preliminary MapsC-BAND Preliminary Maps

X-BAND Preliminary MapsX-BAND Preliminary Maps

Before FlaggingBefore Flagging

After FlaggingAfter Flagging

X-BAND Preliminary MapsX-BAND Preliminary Maps

Future Work on the pipelineFuture Work on the pipeline

Implement the phase selfcal + model fitting in AIPSImplement the phase selfcal + model fitting in AIPS

Improve the Flagging (understand FLAGR)Improve the Flagging (understand FLAGR)

Adapt the script to produce very good models of the Adapt the script to produce very good models of the flux calibrators and the sourceflux calibrators and the source

Perform tests in each band and array configurationPerform tests in each band and array configuration

Future work on B1600+434Future work on B1600+434

Prepare the lightcurves from the dataPrepare the lightcurves from the data

Determine and improve the time delayDetermine and improve the time delay

Test the different scenarios using the Test the different scenarios using the multifrequency lightcurves multifrequency lightcurves

To stimulate your To stimulate your appetite… appetite…

Scintillation / Scintillation / MicrolensingMicrolensing