DIAGNOSIS FROM JET OBSERVATIONS: KINEMATICS (v field: velocity components of the jet knots)

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DIAGNOSIS FROM JET OBSERVATIONS: KINEMATICS (v field: velocity components of the jet knots) a1) RADIAL VELOCITY line shifts: spectroscopy a2) TANG. VELOCITY “proper motions”: imaging - PowerPoint PPT Presentation

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DIAGNOSIS FROM JET OBSERVATIONS:

A) KINEMATICS (v field: velocity components of the jet knots) a1) RADIAL VELOCITY line shifts: spectroscopy a2) TANG. VELOCITY “proper motions”: imaging

B) PHYSICAL CONDITIONS : excitation, density, ionization fraction…. Appropriate flux line ratios: spectroscopy (quite rough estimation from imaging in different filters, however)

A+B) “simultaneously: 3D spectroscopy:

IMAGING: WHAT CAN BE DERIVED FROM?IMAGING: WHAT CAN BE DERIVED FROM?

Obtain images through “narrow-band” ( FWHM ~ 50 A) filters of the HHs field:

HHs emission is mainly “pure line emission” (except near the source) use filters centered on brighter characteristic jet emission lines, eg, Optical: H, [SII] red doublet, [OIII] (less used: extinction and excitation conditions..)

Infrared: [FeII], H2

Morphology: “history” of the mass-ejection

jet/environment interaction

(indirect) evidence on the nature of the jet source and ejection

mechanisms

spatial distribution of the physical conditions through the jet…

Kinematics: VT, from “proper motions”

NARROW-BAND (OPTICAL) FILTERSNARROW-BAND (OPTICAL) FILTERS

Commonly used for HHs (from NOT webpage):

“H” filter [SII] “red” filter

(6563+part of [NII] 6584 A) ([SII] 6717, 6731 A)

Narrow-band (NIR) filtersNarrow-band (NIR) filters

Commonly used for HHs imaging (from ING webpage)

[FeII] 1.64 m (H band)H2 2.12 m (K band)

KINEMATICS:KINEMATICS: TANGENTIAL VELOCITY OF THE KNOTS (VT)

Knots of the jets appear “displaced” relative to the field stars when images obtained at different epochs are compared. By measuring these “displacements” between two epochs, the VT can be obtained (for a knwon distance).

HST high-spatial resolution images have shown the “displacement”of the knot structures with time, with high degree of detai,l in several wellknown HH jets.

HH 111HH 111

HST images from (Hartigan et al..)

Bally et al. (2002), Bally et al. (2002), AJ,123,2627.AJ,123,2627.

HST (1997)HST (1997)

NN

CS *CS *

HH 1HH 1

HH 2HH 2

Bally et al. (2002), AJ,123,2627.

HST (1994); proper HST (1994); proper motions after 5 yrs.motions after 5 yrs.

Bally et al. (2002), AJ,123,2627.

HST (1994); HST (1994); proper motions proper motions in 5 yrs.in 5 yrs.

Arrow:: displacement in 30 yrsArrow:: displacement in 30 yrs

HH 47HH 47HH 47

Proper Proper motionsmotions

Arrows: Arrows: displacement in displacement in 30 yrs30 yrs

Arrows: Arrows: displacemdisplacement in 10 ent in 10 yrsyrs

Proper-motions from ground-based images: two examplesProper-motions from ground-based images: two examples

Summary:1) Obtain several images of the jet field, with appropriate time spacing, through narrow-band filters covering emission from [SII] or H(strong emission lines at visible wavelengths).2) Convert all the images on to a common reference system, using positions of field stars. . Highly recommended: reference stars, well distributed around jet (not always possible, extinction!) . Different images from different instruments: care with their spatial scale!3) Identify each of the knots of the jet in all the images Care! Some structures may have changed with time4) Evaluate the (spatial) displacement of each of the knots, with respect to the (fixed) reference star system, during the time elapsed between two images n pixel/yr n pixel/yr n arcsec/yr : PROPER MOTION (+ distance) n arcsec/yr : PROPER MOTION (+ distance) VVTT (kms (kms-1-1))

Ex. 1: HH 110Ex. 1: HH 110

Reipurt & Bally (90 ´s)

. In Orion B cloud complex (d~450pc). It shows “peculiarities, eg, : rather chaotic morphology exciting source, unknown originated by deflection of HH 270 that collides with a high-density clump (see later)

HH 110

HH 270

Sepúlveda et al., 2011, AA, 527, 41[SII] image, 2.5m INT- 1993

HH 110HH 110

NN ~4 ARCMIN

[SII] image, 2.6m NOT, 2002

HH 110HH 110

Knot identification

10/2002

12/1993

12/1987

HH 110 knot AHH 110 knot A

López et al. 2005, A&A, López et al. 2005, A&A, 432,567432,567

Displacement of knot A from 1987 to 2002(after convert all images on to a common reference system).

Displacement obtained for the HH 110 knot, using images from three epochs

Knot M

2002

1993

1987

HH 110: Proper motions obtained HH 110: Proper motions obtained from a time baseline ~ 15 yr; for a from a time baseline ~ 15 yr; for a distance ~ 450pc distance ~ 450pc VVTT

Ex 2 HH 30Ex 2 HH 30

Mundt et al. A&A, 232, 37 (1990) HST archive

In L1551, TMC (d~140pc)Prototypical jet/disk system. Jet/counterjet structure. “wiggling morphology”. Exciting source, “hidden” (invisible at optical/ir wavelengths)

Anglada et al.,AJ,133,2799

HH 30:[SII] image, 2.6m NOT, 1998

Displacements of the jet knots of HH 30Displacements of the jet knots of HH 30

Anglada et al. 2007, AJ,133,2799

Proper motions of the jet knots of HH 30Proper motions of the jet knots of HH 30

Anglada et al. 2007, AJ,133,2799

HH 30[SII] image, 4.2m WHT, 2010

Displacements of the knots of the HH 30 jet/counterjet system Displacements of the knots of the HH 30 jet/counterjet system

Estalella et al, 2012,AJ,144,61

with a longer time baseline:

Appreciable differentkinematic behaviourjet/counterjet

jet counterjet

HH 30 jet/counterjet proper motionsHH 30 jet/counterjet proper motions

Estalella et al, 2012,AJ,144,61