Karen Kwitter

Williams College

IAU 283

July 26, 2011 NGC 2818

NASA, ESA, Hubble Heritage Team

PN postage stamp images from HST

1936 T. Page letter in Nature NGC 7027 & NGC 7662: Ar, Ne >> Earth

1939 Bowen & Wyse, Lick Obs. Bulletin

NGC 6572, NGC 7027, NGC 7662: ~solar composition

2006-2011 >300 refereed papers in ADS on PN

abundances: familiar elements,

heavier elements, s-process,

molecules, dust

bpc.edu

Péquignot & Baluteau (1994); Baluteau et al. (1995); Zhang, Dinerstein, Sterling et al. (2001, 2008); Liu et al. (2005, 2007); Sharpee et al. (2007)

* *

reflect progenitor’s ISM

*There is some evidence that nuclear processes can affect

these (Pequignot et al. 2000, Dinerstein et al. 2003; Herwig

2005, Wang & Liu 2008, Milingo et al. 2010 – more later)

bpc.edu

bpc.edu

http://en.wikipedia.org/wiki/en:Creative_Commons

s-process

affected by star’s nucleosynthesis

• get 1-D information @ medium resolution; typically ≲150 lines

down to ~1% x Hb

for brighter objects can get deep

spectra w/high S/N; at right, in NGC 7009 Fang & Liu (2011; poster

here) have identified 1170 features

down to ~0.01% x Hb

but, LSS fails to fully utilize the potential of 2D detectors…

WIYN,NOAO,NSF

Milky Way: Kingsburgh & Barlow

Liu & colleagues

Maciel, Costa & colleagues

Milanova & Koltygin

Perinotto & colleagues

Stasińska & colleagues

Henry, Kwitter & colleagues

Magellanic Clouds:

Boroson & Liebert

Leisy & Dennefeld

Maciel, Costa & colleagues

Dopita & colleagues

Stanghellini, Shaw et al.

Vasiliadis & colleagues.

Juan Carlos Casado (TWAN)

Fred Espenak

exploits 2D detectors with serious multiplexing

Tsamis & collaborators; Sandin & collaborators

NGC 5882 Tsamis et al. 2008

Hb

He II 4686 [O III]

4959

IC 3568

NGC 7662, center

Sandin et al. 2008

c

Te

PMAS, Calar Alto FLAMES/Giraffe Argus, VLT

M1-42 (Pottasch et al. 2007) Spitzer/JPL

• Spitzer IRS provided high-

quality spectra covering

important ions of e.g., Ne,

O, S, Ar (& Fe, Si, Mg)

• Need for ICFs is reduced

• Fine-structure lines have

small T-dependence

Pottasch, Bernard-Salas & collaborators

Stanghellini, Shaw & collaborators

Guzman-Ramirez & collaborators

• prominent ions of He, C, N, O

• avoids usually large ICF(N)

• at right, TS01, the most O-poor PN

known (O/H~1/70 x solar)

• IUE quality superseded by HST COS

& STIS; as yet, small database

HST/STIS Cy19 : Dufour et al. – 10 MW PNe

Guerrero et al. – NGC 6543

STIS [N V]

[C IV] He II

[N IV]

TS-01 Stasińska et al. 2010

HST/STIS

• correct reduced slit fluxes for reddening

• calculate Te, Ne, X+i/H+

N-level atom codes

• calculate ICF’s per some recipe or model*

to derive X/H:

*unless you have all relevant ionization stages

ICF(X) = total X abundance

sum of observable X ions

- Whitford 1958

- Miller & Mathews 1972

- Savage & Mathis 1979

- Seaton 1979

- Howarth 1983

- Fitzpatrick 1999

- Clayton, Cardelli & Mathis 1989

• correct reduced slit fluxes for reddening

fl

An example:

For c=1, the corrected ratio of [O II] I3727/I7323 obtained using CCM vs. SM differs by ~15%, leading to ~1000K difference in the

derived T[O II]…

Il (Xi)

I(Hb) f (Te,Ne ) C

N(X i)

N(H)

Abundance Software Te , Ne ,

N(X+i)/N(H+) Il(X+i)/I(Hb)

• calculate: Te , Ne , X+i/H+

…in NGC 6543, the

systematic uncertainty

introduced by the choice

of atomic data is

comparable to or larger

than the statistical

uncertainties for some

temperatures, densities

and abundances.

R. Wesson (private communication)

on the ground… poster by

Wesson;

talk by

Luridiana

N/H

…not a stationary target

T[S II]

•calculate ionization correction factors (ICFs) per a recipe or model* to derive X/H

*unless you have observed all relevant ionization stages

talk by

Gonçalves

ICFs best determined using photoionization

models; otherwise, exploit IP coincidences

• Kingsburgh & Barlow (1994): developed a good set

still used by many

• Henry & Ferland are currently running sets of

CLOUDY models to evaluate ICFs under a wide

range of stellar T*, Ne, and Z.

… so at each step we have an opportunity for

divergence, independent of measured fluxes!

• Georgiev et al. (2008): NGC 6543

NLTE star and wind model agrees

with ORL values for He, C, O (but

not N)

• García-Rojas et al. (2009): observed

several PNe with WC central stars;

t2 ~0.04; no evidence of cool, C-rich

inclusions, even when the central

stars are H-deficient

recent summary by Peña (2011); Bob Rubin’s talk yesterday

• Yuan et al. (2011): NGC 6153 - 3D bi-

abundance model with 800K

inclusions best reproduces observed

spectrum

• Zhang (2008): NGC 7009 - high

resolution line profiles suggest ORLs,

CELs may originate in kinematically

different regions

• Williams et al. (2008): UV absorption

abundances in 3 PNe agree better

with CEL than ORL abundances

(Liu & colleagues) (Peimbert, Torres-Peimbert & colleagues)

This is becoming testable, and will eventually be sorted out…

ADF=(X/H)ORL/(X/H)CEL

posters by

Peimberts; Fierro et al.;

McNabb et al.; R.-Garcia & Peña

: 1D photoionization code (Stasińska 2005)

: 1D photoionization code (Ferland et al. 1998)

: 1D photoionization/shock code (Kewley 2001)

: 1D photoionization code (Rubin et al. 1994)

: Pseudo-3D photoionization code (Morriset 2005)

: fully 3D Monte Carlo photoionization code

(Ercolano et al. 2003)

: 1-D RHD code (Perinotto et al. 1998) – poster by Jacob

X

X

all abundances are

medians; error bars

show characteristic

uncertainties

different He+

recomb coeff

• good agreement

within uncertainties

• O, Ne, Ar ≈ solar N,C > solar

S < solar

DISK BULGE & HALO

MW Disk Magellanic Clouds

Maciel et al. 2010

+: SMC •: LMC •: MW

models: Karakas & Lattanzio 2007, 1-6

M

similar behavior in all 3 galaxies implies similar origin of N, He

log(N/O) vs. He/H

Karakas (2009): 1-6 M

Marigo (2001): 0.8-5 M

log(N/H) vs. log(He/H)

HKB04 all recalculated,

good T & N determinations

• LMC PNe show

negative trend, HBB

• Type I MWPNe

may also

• SMC PNe do not no HBB

Ne vs. O

• Wang & Liu (2008): Ne, O production only at 12+log(O/H) < 8 (<ZSMC)

• Milingo et al. (2010): some evidence for Ne production, based on on comparison with H II regions; no difference between Type I and Type II PNe

• Peimbert et al. (1992); Peña et al. (this meeting): argue that the ICF for Ne (Ne/O=Ne++/O++) is inadequate at low ionization typically found in H II regions

lower limits, offering an explanation for Milingo et al.’s finding

Maciel et al. 2010

+ SMC LMC MW

Maciel et al.: no correlation between

Ne/O and O over >2 dex in O/H

Ne vs. O

Ar follows H II region

trend, but with larger

scatter than Ne…

Sulfur stinks!

posters by

Henry et al.

Jacob et al.

Karakas: 1-6 M

MW disk PNe – Maciel & Costa (2011) LMC/SMC – Stanghellini et al. (2009)

filled: SMC open: LMC

• Average He and N are higher for asymmetric PNe than for

symmetric PNe

• The opposite is true for C.

• Higher O, Ne, S, Ar in asymmetric PNe younger progenitors

Aasymm,symm - Aall

• SMC PNe tend to be C-rich, implying no HBB

talk by

Karakas;

poster by

Sterling et al.

• Sharpee et al. (2007) detected lines of Br, Kr,

Xe, Rb, Ba, and Pb; Te & I (?); Kr, Xe

enhanced

• Sterling & Dinerstein (2008), detected Kr &/or

Se in 81 of 120 PNe:

- Non-Type I: [Se/(O)]ave= +0.36

[Kr/(O)]ave = +1.02 Kr significantly enhanced

- Type I PNe show little s-process enrichment

- Positive correlation between s-process

enrichments and C/O, as expected in TDU

- No significant difference with central star type

• Future progress relies heavily on knowing

transition rates and collision strengths

Se

Kr

• Delgado Inglada et al. (2009): 33 low-ionization PNe

• median 12+log(Fe/H) = 5.85 (4.27 – 6.49)

• depletion range [Fe/H]: -1.01 to -3.2 (=7.50; Asplund et al. 2009)

- Fe > 90% depleted

- Mdust/Mgas ≥ 1.3 x 10-3

- depletion scales with C/O ratio (poster)

poster by

Delgado

Inglada et al.

See also: Rodriguez & Rubin (2005); Stasińska & Szczerba (1999)

• He, C, N, O, Ne, S, Ar, Fe, s-process abundances have been

determined in 10’s -100’s of PNe in the MW and MC’s.

• IR & UV observations have provided some improved results.

• Significant disparities result from different analysis choices.

• O, Ne, and Ar are positively correlated with each other, as

expected. S is problematic. In general, scatterPNe > scatterH2BCG.

• C, N generally exceed solar, consistent with current LIMS model

predictions including TDU; low-C PNe in the Milky Way & LMC

show evidence of HBB.

• Models cover the parameter space of observed abundances

• s-process elements can be significantly enhanced above solar in

non-Type I PNe.

• Fe is significantly depleted in PNe

.

• atomic data for more atoms, wider regimes

- “normal data” for heavy atoms (Sterling poster)

- low-T parameters for light atoms (Fang poster)

• improved ICFs (metallicity; ionization; geometry)

• more 2D abundance studies/3D modeling

• abundance discrepancy resolution

• coordination/testing among 5-LA programs

• understanding the effect of binarity on observed

abundances in CE scenario

• development of a “strong-line method” when direct

Te measurement not possible

(aside from big ground & space telescopes & good spectrographs)

Students: Funding Sources: Jesse Levitt ’08 NSF

Matt Johnson ’07 NASA

Peter O’Malley ’07 U. Oklahoma

Julie Skinner ’07 Williams College

Anne Jaskot ’08 Emma Lehman ’10

Tim Miller (‘G OU)

Collaborators: Dick Henry

Bruce Balick

Reggie Dufour

Gary Ferland

Jacquelynne Milingo Dick Shaw

THE END EL FINAL