Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
KVN
Sept. 22, 2011
Se-Hyung Cho
Observational Studies from AGB to Post-AGB
Stars Using the KVN Telescope
KVN
◆ Key Issues ◆ KVN Single Dish Survey and Monitoring Obs.: Overview and Some Results
○ Two Color Diagram of SiO/H2O Observed Stars etc. ◆ VLBI Observations for Dynamical Evolutionary Studies from AGB to Post-AGB Stars/PPN ○ Asymmetry at AGB Stage ◆ Related VLBI Case Studies of AGB Stars ◆ VLBI Study of Known Water Fountain Sources ◆ Candidate Sources for KVN+VERA Obs.
Coworkers: Jaeheon Kim (Sang-Jun Kim, Kyunghee Univ.), Dong-Hwan Yun (Yong-Sun Park, SNU), Chi-Young Cho (Seong-En Kim, Sejong Univ.), & Youngjoo Yun (KASI)
Contents
KVN
Observational Studies from AGB to Post-AGB Stars Using the KVN : Key Issues
◈ How appears an dynamical evolutionary process from AGB to post-AGB stars/PPN in both maser emission ?
■ Dynamical effect from SiO to H2O maser regions due to stellar pulsation with relations of mass loss mechanism ~ Propagation of pulsation : photosphere – molecular layer – SiO maser
region – dust formation region – 22 GHz H2O maser region ● Kinematics of maser spots ~ inward/outward motion, rotation, proper motion etc.
■ Dynamical evolution from AGB stars to post-AGB/PN : Aspherical morphology, development of bipolarity, jets
■ Spatial structure and mutual relation of SiO and H2O maser emission
KVN
Energy Level Diagrams of H2O and SiO Molecules
KVN : H2O 616-523 22 GHz SiO J=1-0 43 GHz J=2-1 86 GHZ J=3-2 129 GHz
SiO Energy Levels
KVN
KVN Single Dish Survey: Simultaneous Observations of SiO/H2O
H2O 616-523 (22 GHz ) SiO28 v=1, J=1-0 (43 GHz) v=2, J=1-0 SiO29 v=0, J=1-0 ■ AGB stars (2009-2010)
○ Known both SiO and H2O maser sources (166) : Obs. in 2009 (KVN_Yonsei Tel) ▶ J. Kim et al. (2010 ApJS) ○ Known SiO-only maser sources (83) : Obs. in 2009-2010 (KVN_Yonsei & Tamna) ▶ S.-H. Cho et al. (2011 ApJS, in prep.) ○ Known H2O-only maser sources (152) : Obs. in 2009-2010 (KVN_Yonsei & Tamna) ▶ J. Kim et al. (2011 ApJS, in prep.) ○ Statistical analyses ▶ J. Kim et al. (2011, in prep.) ■ Post-AGB stars (2010-2011) (KVN_Yonsei & Tamna) ▶ D.-H. Yun ○ Spectroscopic post-AGB (Suarez et al. 2008): 50/66 sources ▶ 2 detected ○ IRAS, OH/IR post-AGB candidates: 18/168 sources ▶ 3 detected (Ramos-Larios et al. 2009, Sevenster 2002, Nyman et al. 1998 etc.) ■ AKARI/FIS sources (1st 111): post-AGB or proto-stars ? – SiO/H2O (KVN) ▶ 36/111 H2O-only detected – CO (TRAO) ▶ 36/36 detected → Proto-stars, Star Forming Regions
KVN
Time Monitoring Observations Using KVN Single Dish: Relatively Strong SiO/H2O Maser Sources (2009-2011)
■ AGB stars (SRs, Miras, OH/IR stars: about 30-50 sources) ○ Known both SiO and H2O maser sources (~30) ○ Known SiO-only/H2O-only maser sources ○ New interesting SiO/H2O maser sources ■ Bipolar outflow or multiple H2O sources (about 30 sources) ○ WX Psc, BW Cam, V2108 Oph, V1366 Aql, NML Cyg, NV Aur, OH358.23+0.11, IRAS 19069+0916 et al. ■ Water fountain sources (about 10 sources) ■ Post-AGB stars/PPN (about 5 candidate sources) ■ Symbiotic stars (about 6 sources) ◈ Monitoring time intervals : Irregular, 1-3 months etc. ▶ Single dish studies and basic data for VLBI observations ◈ Maser models based on KVN SD and VLBI data (KVN+VERA) ▶ Y. Yun
KVN
● Regions IV&V : PPNs, No 45 : QX Pup (PPN) IIIb : young PPN can be distributed ● LI&RI : associated with post-AGB stars ● Bipolar structure can start already in AGB stage
(Zijlstra 2001)
W43A ◈
W43A
124
117
QX Pup (PPN)
27
113
45
Jaeheon Kim, Se-Hyung Cho, Chung Sik Oh, & Do-Young Byun ApJS, 188, 209, 2010 (KVN_Yonsei Tel)
● SiO/H2O det. ● SiO-only det. ▲ H2O-only det.
Two Color Diagram of both SiO/H2O Maser Sources (166) : Dynamical Evolution & Maser Chronology from AGB to Post-AGB Stars
KVN
Two Color Diagram of SiO-only & H2O-only Maser Sources: Dynamical Evolution & Maser Chronology from AGB to Post-AGB Stars
83 observed stars for SiO-only sources 152 observed stars for H2O-only
KVN
Survey: Post-AGB Stars and AKARI/FIS Sources Dong-Hwan Yun et al.
Known water fountain sources: IRAS 16552-3050
Newly detected post-AGB ?
CO J=1-0, TRAO 14m
KVN
SiO J=2-1 & J=3-2 obs. with 14m tel. (Cho et al. 1998, 2009, Kang et al. 2006)
Time Monitoring Observations: AGB Stars
Semi-regular pulsating star
KVN
Mira variable star
Time Monitoring Observations: AGB Stars
KVN
Time Monitoring Observations: Water fountain sources (Stellar H2O maser jets)
KVN
■ AGB stars ○ SRs, Miras, IRAS sources etc. ○ OH/IR stars ■ Post-AGB stars ○ IRAS, OH/IR, AKARI etc. post-AGB candidates ▶ Expanded SiO/H2O maser survey, monitoring interesting sources ■ AKARI/FIS sources (1st 111) – Specified sources: CH3OH, SiO (v=0) survey
Single Dish Survey: 2011 Oct. -2012 June
Time Monitoring Observations: 2011 Oct. -2012 June
■ AGB stars (SRs, Miras, OH/IR stars) ■ Bipolar or multiple H2O sources ■ Water fountain sources ■ Post-AGB stars/PPN ■ Symbiotic stars ▶ Continue monitoring
KVN
Bipolar outflow source
Asymmetry starts from Mira variable stars
VLBI Observations for Dynamical Evolutionary Studies from AGB to Post-AGB Stars/PPN
KVN
W Hya Semi regular variable: P~360d Distance ~90 pc Bright maser source: OH, H2O, SiO Elongation of the radio Photosphere
Radio photosphere and SiO maser emission
Green filled ellipses: 43 GHz radio continuum, yellow contour: SiO maser, grey scale: H2O maser, using VLA (Reid & Menten 2007)
Green filled ellipses: radio continuum, contour and grey scale: SiO maser, red filled circles: stellar size
KVN
Multi-epoch Obs. of SiO/H2O Masers:
Related Case Studies
0.3″
■ Annual parallax → distance 1.15 kpc ► Proper motion ► Modeling for the kinematics of 3 dimensional circumstellar envelope
Red Supergiant VY CMa with VERA (Choi et al. 2008, PhD thesis)
◈ We expect to trace the development of outward motion from spherical symmetry in SiO maser regions to asymmetric morphology in H2O regions using KVN+VERA
■ Model of molecular outflow superimposed on HST IR image (Ziurys et al. 2007)
SiO
H2O
KVN
SiO Maser Asymmetric Miras : IK Tauri using VLBA, Cotton et al. 2010
SiO v=2 (left), v=1 (right), J=1-0 2004 Nov. 8 (stellar phase 0.53) 2005 Oct. 23 (stellar phase 1.27) 2006 Feb. 3 (stellar phase 1.49)
KVN Monitoring
KVN
Multi-epoch Obs. of SiO/H2O Masers: Bipolar Outflow from the WX Pisces
NIR 1.24 µm (J band), Hofmann et al. 2001
Ring-like distributions of SiO v=1, 2, J=1-0 by VLBA, Soria-Ruiz et al. 2005
By KVN
◈ Bipolar outflow triggered at a late stage of AGB winds ● Symmetry breaking in the evolution from AGB to planetary nebula ? ● Precursor of water fountain ? Vinkovic et al. 2004
Biconically expanding flow model based on H2O maser by JVN, Inomata et al. 2007
KVN
Time Monitoring Observations Using KVN SD:
water fountain sources
KVN
Parameters of Known Water Fountain Sources
Imai 2007
KVN
Vinkovic et al. 2004
(WX Psc)
MSX Color-Color Diagram of Known Water Fountain Sources & IRAS 19069+0916
KVN
JVN, Imai et al. 2008
NRO 45m, Deguchi et al. 2007
VLBI Observations of Water Fountain Sources
OH 12.8-0.9, Boboltz 2005
KVN
Double-jet model based on VLBA obs. Yung et al. 2011
IRAS 18286-0959
KVN
KVN
IRAS 19134+2131, VLBA (Imai 2007)
IRAS 16552-3050, VLA (Suarez 2008)
-23 ~ -10 km s-1 -121~ -117 km s-1
HST image by R. Sahai : Optically visible ▶ Pre-Planetary Nebulae phase Dynamical age ~ 50 yrs
VLBI Observations of Water Fountain Sources
KVN
IRAS 16342-3814, Claussen et al. 2009
VLBI Observations of Water Fountain Sources
VLBA
VLA
HST F814W
KVN
Post-AGB Star, W43A : The H2O masers exist in a precessing jet
SiO v=1, J=1-0 Imai et al. 2005,
VLBA, Imai et al. 2002
Vlemmings et al. 2006
KVN
Candidate Sources for KVN (+VERA) Obs. of SiO & H2O Masers
Based on KVN single dish survey and monitoring observations ■ SR, Mira, SG: RT Vir, IK Tau, W Hya, RR Aql, R UMa, V1111 Oph, NV Aur (O), WX Psc (D: BO), NML Cyg (D: BO), V438 Sct (D), V4201 Sgr (M), V2108 Oph (D/M), OH358.23+0.11 (M) et al. * According to H2O line profiles; O ► One-way, D: BO ► Double peaks: Bipolar Outflow, M ► broad Multiple H2O sources ■ Symbiotic stars: V407 Cyg, V627 Cas ■ Water fountain sources/PPN: IRAS 19069+0916, OH9.1-0.4, W43A ?