hi beth, thanks for the reminder. i was under the mistaken impression that this had been taken care of at yr end (since there isn't any change in the coordinates). but i realize that i probably failed to have communicated this to you! regards raghvendra ----- Submission 1 (Fri May 19 18:31:35 GMT 2006) ----- Phase II Proposal 10851 (rr) successfully submitted. ----- Submission 2 (Mon Jul 10 17:48:33 GMT 2006) ----- Assigned ID: 565 ----- Submission 1 (Fri Jan 27 23:44:58 GMT 2006) ----- Phase I Proposal 565 (rr) successfully submitted. ----- Submission 2 (Sat Jan 28 00:45:21 GMT 2006) ----- Phase I Proposal 565 (rr) successfully submitted. Solving the Riddle of the Red Rectangle: Proper Motion Study of a Bipolar Nebula around a Binary We propose to use ACS to obtain second-epoch, high spatial-resolution images of the nearest Pre-Planetary nebula, the Red Rectangle (RR). The RR is a Rosetta Stone for testing our understanding of binarity in the evolution of AGB stars to bipolar planetary nebulae, because it is a known binary with well determined orbital and circumbinary disk characteristics, and because of its proximity (330-700 pc). Recent analysis of archival STIS data shows evidence for outflow motion of about 100 km/s. Thus, 2nd epoch observations, in combination with those of 8 years ago, will yield a direct detection of proper motion of sharp nebular structures and the overall expansion rate of this nebula. The observations will therefore detect and characterise for the first time, the outflow motions of a (possibly) disk-collimated outflow from an evolved binary shaping a bipolar nebula. Deep narrow-band imaging of the RR using the HRC and WFC with the F658N filter will be used to trace H-alpha emission in the central and distant parts of RR, as a probe of the shocked gas. We will run numerical simulations of two currently competing models for shaping the RR, using the FLASH MHD code. This code has been implemented on the JPL supercomputer to study interacting wind processes in the formation of pre-planetary and planetary nebulae. The model predictions of the proper motion vectors will be compared to the observed values, and we will investigate whether tuning of the model parameters is adequate to find fits to the data, or these models have to be abandoned in favor of new ones. This study will help to improve our currently very limited understanding of the role of binarity in the tranformation of AGB stars to planetary nebulae.
We will obtain images in the ACS/WFC camera using the F625W filter, and with comparable exposure times, in order to provide close matches to the images obtained with the WFPC2 PC camera. Since the nebula is very bright, we will use a total exposure time of 600 sec, including short exposures to obtain unsaturated images of the bright central parts (for comparison, the WFPC2 images were obtained with one 0.7 sec and three 40 sec exposures). The images through the H$\alpha$+[NII] filter, F658N, will be much longer (about 50 min) - the ground-based H$\alpha$ data reported in CVBG04 was obtained using the 3.5m NTT with a 1200 sec exposure. Hence, we will use 2 orbits to obtain the WFC images in the F625W and F658N filters, with the bulk of the time being devoted to the F658N image. We will allocate 2 orbits to obtain high-quality HRC images in these two filters, with a similar division of the exposure time between the broad-band and narrow-band filter. All images will be dithered and cosmic-ray split. We have verified that the requested exposure times will produce high signal-to-noise images, using the Exposure Time Calculators, and the observed intensities from our WFPC2 and ground-based images (for H$\alpha$). Comparison of the WFPC2 and the WFC images to derive proper motions will not be difficult. First, the overall expansion motions from the center can be derived by simply measuring the separation of identical structures on opposite sides of the center of the nebula for each epoch. Secondly, the plethora of well-defined sharp structures in the nebula make it easy to identify well-defined, localised comparison points in the two images for registration and alignment. Expansion motions of PNs from HST images have been succesfully determined using well-tested techniques by several PN researchers (e.g., Hajian, Terzian, Balick), so we do not anticipate any difficult in doing this for the RR. COOL STARS 12 false 0.0 false false false false false SUPPORTED ISM PLANETARY NEBULA REFLECTION NEBULA J2000 06 19 58.2160 -10 38 14.70 J2000 ACS/HRC Imaging No No F658N ACS/HRC Imaging No No F625W ACS/WFC Imaging No No F625W ACS/WFC Imaging No No F658N POS-TARG DITHER 0.15 LINE 0.098 false true 63.5 4 19.89 ACS-HRC-DITHER-BOX 1 false POS-TARG DITHER 0.198 LINE false true 2 44.28 ACS-HRC-DITHER-LINE 2 false POS-TARG DITHER 3.011 LINE false false 2 85.28 ACS-WFC-DITHER-LINE 3 false /tmp/OPVisit41066.xml (Tic-Visit :proposal-id 10851 :visit-id "01" :proposal-version -1 :trans-version "20060322" :date "10-Jul-2006 10:47:17.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 662464 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10851 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10851 :visit-id "01" :orbit-number 1 :pcs-time 355 :si-vis-utilization 2737 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3137 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10851 :visit-id "01" :orbit-number 2 :pcs-time 355 :si-vis-utilization 2776 :al-overhead-at-end 0 :internal-dur-at-end 300 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3137 :pcs-gap 0 ) true 2 0 /u4/sahai/proposal/cyc15/OP-cache/rr-v01.xml /tmp/OPVisit41067.xml (Tic-Visit :proposal-id 10851 :visit-id "02" :proposal-version -1 :trans-version "20060322" :date "10-Jul-2006 10:47:33.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 2267312 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 10851 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 10851 :visit-id "02" :orbit-number 1 :pcs-time 355 :si-vis-utilization 2776 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3137 :pcs-gap 0 ) (Tic-Orbit :proposal-id 10851 :visit-id "02" :orbit-number 2 :pcs-time 355 :si-vis-utilization 2775 :al-overhead-at-end 0 :internal-dur-at-end 349 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3137 :pcs-gap 0 ) true 2 0 /u4/sahai/proposal/cyc15/OP-cache/rr-v02.xml