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					Binarity & Symbiotics

            Hugo E. Schwarz.
Cerro Tololo Inter-American Observatory,
              NAOA/AURA.
       Asymmetries in PNe.
• Most field stars are unpolarized.
• 3/4 of AGB stars is polarized.
    (Johnson, Jones 1991, AJ 101, 1735)
•   Most PNe are not circular, many are extreme.
•   Some ~50% have binaries.
•   Extreme global asymmetries due to binaries.
•   Point symmetry due to precession.
•   Links to symbiotics & symbiotic nebulae.
•   Different properties of bipolar PNe.
                       Asymmetric PNe 28 Jul - 1 Aug 2003   2
    Bipolar properties
    • Scale height 130pc v. 260pc
   • Nearer pure circular Galactic
                rotation
• Hotter central stars 145kK v. 75kK
  • He, N, & Ne are overabundant
  • Vexp higher 150km/s v.15km/s
     • Large size 0.76pc v. 0.1pc
   • More massive progenitors
           >1.5M
            Asymmetric PNe 28 Jul - 1 Aug 2003   3
Bipolars-Symbiotics-PNe
•   40% of D&D’ symbiotics have nebulae.
•   Post-PN nebulae: BI Crucis (3 nebulae).
•   AS201 fossil PN, ionized nebula, G star.
•   5/14 symbiotic nebulae are bipolar.
•   Binaries explain both phenomena.
•   M2-9 needs faint, hot star  binary.
•   Blue-red shifts in the same lobe (IC4234).
•   Point symmetry explained by precession.
                  Asymmetric PNe 28 Jul - 1 Aug 2003   4
  Symbiotics with optical nebulae
               Corradi et al. 1999 A&A 343, 841
Name               Type        Size[“]           Shape      Vexp [km s-1]

AG Peg   (?)         S            8         irregular

AS 201            yellow          13        elliptical          16
BI Cru              D            150        bipolar+jet      up to 280
CH Cyg               S            32        jet+irregular    >65 (>>?)
H 1-36              D          0.9-1.5
H 2-2    (?)         S           1.4
HBV 475              S           0.4        irregular
He 2-104            D             95        2 bipolar+jet     6 to 240
He 2-147            D             5         ring                 100
HM Sge              D             30        irregular           >65
R Aqr               D            120        bipolar+jet      55 to 500
RX Pup              D             4         bipolar?            >80
V417 Cen          yellow         100        bipolar              10:
V1016 Cyg           D             20        elliptical          >30
                      Asymmetric PNe 28 Jul - 1 Aug 2003                    5
Symbiotic nebulae



  Asymmetric PNe 28 Jul - 1 Aug 2003   6
    Symbiotic nebulae (SyNe)
•   Nearly 4 times more are bipolar cf. PNe.
•   Average Vexp is 140km/s as for BPNe.
•   Average z = 133pc as for BPNe.
•   For BSyNe z = 98pc (only 5 objects)
•   Most have [NII] as strongest lines.
    • SO SYMBIOTIC NEBULAE SHARE
       MANY PROPERTIES WITH BPNe
                & are binaries…
                Asymmetric PNe 28 Jul - 1 Aug 2003   7
                                              BI Cru
                                 Post-PN-Nebula
                                 Schwarz & Corradi 1992, AA 265, 37
                                 Model of Morris 1987, PASP, 95, 1115

                                                         Vexp = 280 km/s
                                                         VH = 3000 km/s
                                                         Central reversal
                                                         2 nebulae: H/L exc.
                                                         D = 1.8kpc
High excitation nebula                                   S = 1.3pc, Age = 3ka
(unresolved)                                             L = 4300L



                         Asymmetric PNe 28 Jul - 1 Aug 2003                     8
            M2-9: PN & symbiotic
 Size = 115“, outer lobes point symmetric,
    Inner nebula has plane symmetry.
        Outer lobes reflecting dust
L=553L; d=640pc; age=1200yrs; s=0.37pc

 Both plane and point symmetries due to
 binary orbit phenomena: rotating                        HST image
 central dustclouds and precession?
 “Symbiotic“ emission lines, prob. disk.
 [OIII] line, so hot, subluminous *:
 WD+MS or RG are present = binary.
         Schwarz et al. 1997 AA 319, 267
                        Asymmetric PNe 1339
         Doyle et al. 2000 AJ 119, 28 Jul - 1 Aug 2003    9
Sa2-237                              Vexp=308km/s
                                     S = 0.37 pc 34”
                                     L = 340 L
                                     D = 2.1kpc
                                     Age = 624 a

               As M2-9: [OIII] present, low L,
               so WD, so binary. Study CS….




Asymmetric PNe 28 Jul - 1 Aug 2003               10
   AS201: P-PN-N in the making?
Schwarz 1991 A&A 243, 469

                                  Low excitation nebula,
                                  old, faint, extended.
                                  High excitation inner nebula.
                                  Symbiotic & PN.

                                  When CS forms disk…
  AS 201                          get an object like BI Cru?
                            Asymmetric PNe 28 Jul - 1 Aug 2003   11
             A79, He2-428, M1-91
Rodriguez, Corradi, Mampaso 2001 AA 377, 1042
Strong mass loss/exchange in unresolved cores.
CaII triplet in emission, high , excretion disk.
Cont. and absorption lines indicate hot star with cool companion.
Equatorial rings and polar lobes.




                      Asymmetric PNe 28 Jul - 1 Aug 2003    12
Precession, point symmetry
Red and blue shifts on the
   IC4634
same side of the object.
   Long or Sky cut
Only if LoSslit spectrum.
precession cone.
  V
  E
  L    Observed in IC4634
  O
  C
  I
  T
  Y
                        SPATIAL
               Asymmetric PNe 28 Jul - 1 Aug 2003   13
Random distribution on the sky.
Number of objects at inclination, i,  sin(i).
For a precession cone with opening angle 2 ,
only those objects with

0 < i  or /2  < i /2 where 0 <  /4
               

will show red and blue shifts on the same side of
the central object (RB effect).
Integrating between 0 &  and /2  & /2 we get:
                                      

f( ) = 1   ) + sin( )
           cos(

which is near linear with inclination angle.
So for a typical opening angle of 30o the fraction of
                   the RB effect is about 30%.
objects that showAsymmetric PNe 28 Jul - 1 Aug 2003     14
            Strong links:
       PNe-Symbiotics-Binaries
•   All (extreme) bipolars are binaries
•   All symbiotics are binaries
•   Evolutionary stage is important (P-PN-N)
•   Some equatorial density enhancement
•   Orientation effects should occur
•   Model these, cf. observations.


                Asymmetric PNe 28 Jul - 1 Aug 2003   15
       Inclination effects.
    High inclination objects hide the central
       object behind their equatorial mass
    concentration, and therefore show more
      FIR radiation; low inclination objects
        show the central object and this
     increases the fraction of visible & NIR
                  light we see.

                       So…
Computing the UBV (VIS), JHK (NIR), & IRAS (FIR)
relative fraction of the total flux, we should see an effect.
                   Asymmetric PNe 28 Jul - 1 Aug 2003       16
Crude model of inclined nebulae

•   Donut (BB) around point source (BB)
•   Stellar flux captured is converted to IR
•   Random i orientation in space
•   Plot fractions of BVR, JHK, & IRAS (i)
•   Cf. observations for various BBs:
•   Donut 600K; Star 10, 20, 40, 80kK

                Asymmetric PNe 28 Jul - 1 Aug 2003   17
        Observed sample
• ~30 objects, partial SEDs, some distances
• Estimate inclinations from images (3x)
• Use BVR, JHK, IRAS “bands” relative to
  sum of these bands.
• Do same for simulation data, compare.



             Asymmetric PNe 28 Jul - 1 Aug 2003   18
Observed
 sample                                           FIR




                                                VIS & NIR



           Asymmetric PNe 28 Jul - 1 Aug 2003               19
         Random sample
       • Generate random binaries.
     • i random with sin(i) histogram
  • Donut dust distribution, 15% stellar
• Plot same parameters as observed data.



              Asymmetric PNe 28 Jul - 1 Aug 2003   20
          sample
 Random 1000WD
    1000WD
    200RG
 = FIR    = NIR 200RG
                    = VIS
           200K dust dust
                 400K




             Asymmetric PNe 28 Jul - 1 Aug 2003   21
                 High inclination (>45)
                 LUMINOSITIES
Sa2-237        I=70             2.1kpc              340 Lo
   Another predicted effect0.64kpc inclination objects
M2-9           I=75           is that high          553 Lo
               I=50               1kpc              205 Lo
He2-104have lower apparent luminosities due to the fact
   should
    that only I=70              2.8kpc              440 Lo
He2-111 the equatorial “donut” is seen, while for low
M1-16          I=70            1.8kpc               194 Lo
 inclination the central object plus donut is observed giving
                                                    346 Lo
   an apparent over-luminosity. Over all angles, averaging
                  Low inclination (<45)
  makes sure that no energy conservation laws are broken;
                          Ltot = n.Lave
 R Aqr         I=20          0.2kpc               2800 Lo
 BI Cru        I=40           1.8kpc              4300 Lo
                                                   3550
 Distances being uncertain for all but a few objects, we Lo
 have:
There is some indication of lower luminosities being
           associated with high inclinations.
                   Asymmetric PNe 28 Jul - 1 Aug 2003     22
Luminosity v. inclination
from the same simulation.




      Asymmetric PNe 28 Jul - 1 Aug 2003   23
                          Statistics
 Note that the number of objects increases with inclination as sin(i); this
is expected just from the statistics of randomly orientated objects, and is
strengthened by observational selection of bipolars by their morphology.
  Objects that are (near) pole-on are not recognized as bipolars and are
                        therefore selected against.
                                  We have:


                         0 - 30            3 objects
                         31- 60           11 objects
                         61- 90           14 objects



 This is the expected behavior and is of the right order but there are too
                     few objects to make this harder.
                          Asymmetric PNe 28 Jul - 1 Aug 2003       24
              Conclusions

          • PNe, SyNe are linked.
  • PNe, SyNe are often indistinguishable
• Asymmetrical nebulae         have binaries.
                                      ( nearly always)



    • Orientation effects are important
      in interpreting & constraining
               observations.

               Asymmetric PNe 28 Jul - 1 Aug 2003        25

				
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