Upload
clinton-gomez
View
26
Download
1
Embed Size (px)
DESCRIPTION
What does Ammonia trace in Egg Nebula. Pao-Jan Chiu With Jeremy Lim 2003 8.27. Outline. Optical Structure of the Egg Nebula 12 CO Molecular Outflows Structure of NH 3 (1,1) Observations with VLA Results and Discussion Summary. CRL2688 - Egg Nebula. Proto-Planetary nebula (PPN) - PowerPoint PPT Presentation
Citation preview
What does AmmoniaWhat does Ammonia trace in Egg Nebulatrace in Egg Nebula
Pao-Jan ChiuPao-Jan ChiuWith With Jeremy LimJeremy Lim
2003 8.272003 8.27
OutlineOutline
Optical Structure of the Egg Nebula 12CO Molecular Outflows Structure of NH3(1,1) Observations with VLA Results and Discussion Summary
CRL2688 - Egg CRL2688 - Egg NebulaNebula
Proto-Planetary nebula (PPN) Distance ~ 1 kpc Optical features
• bipolar lobes• twin searchlight beams• quasi-spherical AGB wind• shocked molecular hydrogen• “dust lane”
Multiple Outflows in Egg Multiple Outflows in Egg nebulanebula
12CO trace multiple outflows. Shocked molecular hydrogen traces lobes of
polar outflow, tips of “equatorial” outflows.
Arrow – axis of Arrow – axis of 1212CO outflows contour – CO outflows contour – 1212CO CO color – optical image + shocked Hcolor – optical image + shocked H2 2
NHNH33(1,1) in Egg nebula(1,1) in Egg nebulaEquatorial disk or central toru?Equatorial disk or central toru?
Nguyen-Q-Rieu, A. Winnberg, V. Bujarrabal ,1986Nguyen-Q-Rieu, A. Winnberg, V. Bujarrabal ,1986VLA D array, beamsize 4”.3 × 3”.4VLA D array, beamsize 4”.3 × 3”.4Redial velocites from -63.5 to -23.9 km/sRedial velocites from -63.5 to -23.9 km/s
NH3(1,1) aligned with the dust lane Kinematics suggest expansion: Expanding Disk Spur to north?
Bipolar lobes
NH3(1,1)
-75~ 5km/s
-63.5~-23.9km/s
ObservationsObservations
observerobserver VLA D-arrayVLA D-array
objectiveobjective NHNH33(3,3) in Egg(3,3) in Egg
frequencyfrequency 23.874 GHz23.874 GHz
wavelengthwavelength 1.3 cm1.3 cm
bandwidthbandwidth 12.5 MHz12.5 MHz
velocity rangevelocity range -110.4 -110.4 ~ ~ 46.4 46.4 km/skm/s
bandwidth pre bandwidth pre channelchannel
195.3 Hz195.3 Hz
( 2.454 km/s )( 2.454 km/s )
beam size beam size 3.19”×2.51”3.19”×2.51”
Results and Results and DiscussionDiscussion
•At higher angular resolution, structure of NH3(3,3) does not resemble disk
Beamsize 4”.3 Beamsize 4”.3 ×× 3”.4 3”.4 Beamsize 3”.19 × 2”.51Beamsize 3”.19 × 2”.51
NH3(1,1)
Comparison of NH3(3,3) andNH3(1,1)
NH3(3,3)
Compare with optical lobes Compare with optical lobes and shocked Hand shocked H22
•NH3(3,3) traces higher density (~105-106) and higher temperature (~120K) than 12CO (2-1)
•The four NH3(3,3) peaks are at/close to tips of 12CO outflows.
•NH3(3,3) traces shocked molecular gas behind the shock front (traced by shocked molecular hydrogen) color – optical image + shocked H2 color – optical image + shocked H2
contour – NHcontour – NH33(3,3) contour – (3,3) contour – 1212COCO
outflowsoutflows
1212CO CO
1212CO CO
Shock Shock regionregion
Shock Shock regionregion
Shock Shock regionregion
cooling regioncooling region
ShockShocked ed HH22
NHNH33(3,(3,3) 3)
1212CO CO
1212CO CO
1212CO CO
1212CO CO
1212CO CO
1212CO CO
cooling regioncooling region
ShockShocked ed HH22
NHNH33(3,(3,3) 3)
ShockShocked ed HH22
Compare with optical lobes Compare with optical lobes and shocked Hand shocked H22
•NH3(3,3) traces higher density (~105-106) and higher temperature (~120K) than 12CO (2-1)
•The four NH3(3,3) peaks are at/close to tips of 12CO outflows.
•NH3(3,3) traces shocked molecular gas behind the shock front (traced by shocked molecular hydrogen) color – optical image + shocked H2 color – optical image + shocked H2
contour – NHcontour – NH33(3,3) contour – (3,3) contour – 1212COCO
Velocity distribution in NHVelocity distribution in NH3 3
•North and east NH3(3,3) peaks are blueshifted•South and west NH3(3,3) peaks are redshifted •Kinematics of NH3(3,3) similar to 12CO outflow
NHNH33(3,3)(3,3)
Contour -Contour - 12 12COCOColor arrow - Color arrow - 1212CO outflowsCO outflows
SummarySummary Observed NH3(3,3) in Egg Nebula with VLA NHObserved NH3(3,3) in Egg Nebula with VLA NH33(3,3) trac(3,3) trac
e the higher density and temperature e the higher density and temperature moleculemolecule gas gas NHNH33(3,3) (3,3) not consistentnot consistent with expanding disk with expanding disk NHNH33(3,3) located at/close to tips of (3,3) located at/close to tips of 1212CO outflows and behiCO outflows and behi
nd the shocked molecular hydrogen gas nd the shocked molecular hydrogen gas Kinematics of NH3(3,3) similar to Kinematics of NH3(3,3) similar to 1212CO outflowsCO outflows NH3(3,3) traces NH3(3,3) traces shocked molecular gasshocked molecular gas behind the shoc behind the shoc
k front (traced by shocked molecular hydrogen)k front (traced by shocked molecular hydrogen) Does the “equatorial” outflows lie in the same plane; i.e., dDoes the “equatorial” outflows lie in the same plane; i.e., d
isk that is aligned with the dust laneisk that is aligned with the dust lane
Orientation of the Multiple Orientation of the Multiple “Equatorial” Outflows“Equatorial” Outflows
Two models: Model 1. Oriented in different directions, with no
common plane
Model 2. “Equatorial” Outflows lie in the plane of a “disk” aligned with the dust lane
Orientation of the Multiple Orientation of the Multiple “Equatorial” Outflows“Equatorial” Outflows
Two models: Model 1. Oriented in different directions, with no
common plane
Model 2. “Equatorial” Outflows lie in the plane of a “disk” aligned with the dust lane
Model 2 requires the “disk” to be (rapidly)
rotating
Thank Thank you !!you !!