atomic processes in photoionized gaseous nebulae

北京大学物理学院天文学系北京大学科维理天文与天体物理研究所http://vega.bac.pku.edu.cn/astro/astro.htm http://kiaa.pku.edu.cn/

Atomic processes in photoionized gaseous nebulae

Xiaowei LiuDoA and KIAA-PKU ([email protected])

IAU Symposium No 283, Planetary Nebulae: an Eye to the Future, Puerto de la Cruz, Tenerife, Spain

Thanks: PKU: Xuan Fang, Haibo Yuan, and Ian McNabbHKU: Yong ZhangUCL: Pete J. Storey and M. J. Barlow

http://vega.bac.pku.edu.cn/astro/astro.htm

http://kiaa.pku.edu.cn/


Layout

• Atomic processes, plasma diagnostics and abundance determinations

• New calculations of atomic data since 2006

– Collision strengths

– Photoionization cross-sections and recombination rates

– Radiative data

• New plasma diagnostics based on recombination spectra




PNe: Low density plasmas ionized and heated by diluted UV radiation fields (NLTE)

Cooling

H0 + hν ⇔ H+ + e−

Recombination

Photoionization

Heating

e− e−

ionizationrecombination

hν > 13.6 eV

hνcn

hνnn

line em.

cont. em.

Ionizing photons Ne = 102 – 106 cm−3

Te = 5,000 – 20,000 K

(for cosmic composition)

H+

He+

He++

O3+O++

O+

*T

ex

0163440

29170

62137

86797

012

5007

4931

4959

4363

2321

2331

1661

1666

1D2

1S0

5So2

3P

88µm 52µm

[O III] 2p2,2s2p3

5003500

6.9 105

2.5 107

3.4 1010

Nc

O2+ + e− → O2+* + e− → O2+ + hν + e−

Cooling

Collisional excitation

Strömgren spheres

Ionization and thermal structures determined by micro-physical processes: Photoionization(aν), Radiative and di-electronic recombination (α

R, α

D), CXT, ion-electron collisions (ϒ)




CELsjν ∝ T

e-1/2exp(-T

ex/T

e)

jν ∝ N(X+i)N

e for N

e << N

c

∝ N(X+i) for Ne >> N

c

jν increases as Te increases

H I Recombination lines/continua[O III] Collisionally excited lines

ORLs/Cont.jν ∝ T

e−α where α ∼ 1

jν ∝ N(X+i+1)N

e

jν decreases as Te increases

Weak dependence on Ne

Tex

0163440

29170

62137

86797

012

5007

4931

4959

4363

2321

2331

1661

1666

1D2

1S0

5So2

3P

88µm 52µm

[O III] 2p2,2s2p3

5003500

6.9 105

2.5 107

3.4 1010

Nc

O II 2p2nl ORLs

RecombinationO2+ + e− → O+ + hν

Lyman

3

2

1

Balmer

Paschen

PhotoionizationHeating

RecombinationCooling

Paschen cont.

Balmer cont.

10.2

eV =

11 2

,816

K

2p3

2s2p4

3s

3p3p

3p

3d3d3d4s

4d5s5d 5d 5f

5p4f4p

4d4d 4f

5f 5f

4f

4So 4Po4P 4F4Do 4Fo 4G4D

115125

185

205

225

245

265

Ene

rgy

(103 c

m−1

)

0

M1

M10

M48

M2

M11M12

M19M20

M28

4Go4S

3p 4Do

J = 3/2

J = 7/2

J = 5/2

J = 1/2

464

94

642

463

9

M1

O2+ + e− → O2+* + e− → O2+ + hν + e− H+ + e− → H0* → H0 + hν

Plasma diagnostics:• Te

and Ne

• and stratifications/inhomogeneities

Abundance determinations:• Ionic abundance ratios Xi+/H+

• ICFs• Inhomogeneities




Keenan, F. P., et al., “Ultraviolet and extreme-ultraviolet line ratio diagnostics for O IV”, 2009, A&A, 495, 359

max. O3+

O IV




Tayal, S. S., “Oscillator Strengths and Electron Collision Rates for Fine-Structure Transitions in O II”, 2007, ApJS, 171, 331Tayal, S. S., “Electron impact excitation of forbidden and allowed transitions in O II”, 2006, JPhB, 39, 4393Montenegro, et al., "Relativistic and Correlation Effects in Electron Impact Excitation of Forbidden Transitions of O II", 2006, JPhB, 39, 1863Pradhan, et al., "[O II] Line Ratios", 2006, MNRAS, 366, L6

ϒ(4S3/2

– 2D5/2

)/ϒ(4S3/2

– 2D3/2

) = 1.5Relativistic effects insignificant amongst the 2p3 ground configuration

O II




Tayal, S. S. and Zatsarinny, O., "Breit-Pauli Transition Probabilities and Electron Excitation Collision Strengths for Singly Ionized Sulfur", 2010, ApJS, 188, 32

70 bound levels of S II covering all possible terms of the ground 3s23p3 and singly excited 3s3p4, 3s23p23d, 3s23p24s, and 3s23p24p configurations, involving a total 2415 transitions between fine-structure levels.

ϒ(4S3/2

– 2D5/2

)/ϒ(4S3/2

– 2D3/2

) = 1.5

S II




Péquignot, D., “Heating of blue compact dwarf galaxies: gas distribution and photoionization by stars in IZw 18”, 2008, A&A, 478, 371

O III

∼ 4% for 3P −1D

∼ 10% for 1D− 1S (6% in I Zw18 conditions)




3P0 – 3P

13P

1 – 3P

2

Tayal, S. S., “Electron Excitation Collision Strengths for Singly Ionized Nitrogen”, 2011, ApJS, 195, 11

N II




Storey, P. J., Zeippen, C. J., “Atomic data from the IRON project. LXVII. Electron impact excitation of Fe XIII”, A&A, 511, 78

Fe XI

Fe XIII

Del Zanna, G., Storey, P. J., Mason, H. E., “Atomic data from the IRON project. LXVIII. Electron impact excitation of Fe XI”, A&A, 514, 40




(Blue-shifted) shock component: Ne = 2890 cm−3

(Red-shifted) nebular component: Ne = 17,430 cm−3

Te = 9000 K

Mesa-Delgado A., et al., 2009, MN, 395, 855

Bautista, M. A., Ballance, C. P., Quinet, P., “Atomic Data and Spectral Model For Fe III”, 2010, ApJL, 718, L189

[Fe III]

See also Poster by Zhang et al.




PI cross-sections and recombination rates for n-capture elements

Sterling, N. C., “Atomic data for neutron-capture elements II. Photoionization and recombination properties of low-charge krypton ions”, arXiv:1107.3843Sterling, N. C., Witthoeft, M. C., “Atomic data for neutron-capture elements. I. Photoionization and recombination properties of low charge selenium ions”, 2011, A&A, 529A, 147




Bruhns, H., et al., “Low-energy charge transfer for collisions of Si3+ with atomic hydrogen”, 2008, PhRvA, 77, 4702

Cross-section measures at energies 44 – 2500 eV/uSi3+ + H0(1s) → Si2+ + H+

Multicharged Ion Research Facility

Molecular orbital Close coupling

Classical trajectoryMonte Carlo




Liu, J. R., Mao, S. D., Wang Q. D., “Charge-exchange X-ray emission of M82: Kα triplets of O VII, Ne IX and Mg XI”, 2011, MN, 415, 64

The flux contribution of the CXE is 90, 50 and 30 per cent to the O VII, Ne IX and Mg XI triplets, respectively.

Lisse et al., “Discovery of X-ray and Extreme Ultraviolet Emission from Comet C/Hyakutake 1996 B2”, 1996, Sci., 274, 205

Dennerl, K., “Charge transfer reactions”, 2010, Space Sci. Rev., 157, 57

Important in PNe?See Posters byGuerrero et al.

O VI abs/em detected




Good agreement between T

e's deduced from the two

line ratios, except thatT

e(λ7281/λ5876) may have

been underestimated due to self-absorption effects from the 2s 3S metastable level.

Te(He I) < T

e (H I)

Consistent with the expectations of the two-abundance model

Zhang et al., 2005, MNRAS, 358, 457

But see Poster by A. Peimbert & M. PeimbertHe I temperatures in planetary nebulae




Zhang et al., 2009, ApJ, 695, 488

He I λ3421 discontinuity

He I line ratios

H I λ3646 Balmer discontinuity

Single abundance model

2-abundance model

He I F(J3421)/F(λ3634)

H I

F(J

3646

)/F

(H11

)




NGC 6153

2p 3Po – nd 3D series OK

2p 3Po – ns 3S series Strengthened

2s 3So – np 3Po series Weakened

2p 1Po – nd 1D series OK

2p 1Po – ns 1S series Weakened by 40%

2s 1So – np 1Po series Weakened by factors 2 – 3

Self absorption from the 2s 3S metastable level

Departure from pure case B to Case A?

Destruction of He I Lyman line photons by photoionization of H0 and/or by dust grains?

Liu et al. 2000, MNRAS, 312, 585Liu et al. 2001, MNRAS, 327, 141




86 PNe

solar

1) T eORLs/Cont.T eCELs 2) X i+

H +ORLsX i+

H +CELs

Plasma diagnostics and heavy elemental abundance determinationsCollisionally excited lines versus recombination lines/continua

Conclusions: The nebulae contain another component of plasma of vastly different physical conditions (T

e ∼ 1000 K) and chemical composition (CNONe enhanced by a factor of ∼100)

in the form of H-deficient inclusions. Origins?

Need of new atomic data valid at such low Te's and (ORL-based) diagnostic tools to probe

the physical conditions (Ne – mass, T

e), chemical composition, sizes and spatial distribution.

Liu 2006, Proc. IAUS 234, p.219




The model predicts: T

e([O III]) = 8800 K >> T

e(H I BJ) = 6080 K >> T

e(He I J3421) = 3300 K >> T

e(O II ORLs) = 800 K

Photoionization models of NGC 6153Yuan et al. 2011, MN, 411, 1035

HST imagesH α [O III] λ5007

Te= 9007 K

NH= 1840 cm−3

ff = 0.998M = 0.243 M

sun

Te= 815 K

NH= 4000 cm−3

ff = 0.002M = 0.0031 M

sunH-deficient knots are cooled by infrared fine-structure lines:[O III] 52μm, [Ne II] 12.8μm and [Ne III] 16μm

Chemically homogeneous model

Normal componentH: 10000 He: 1000 C: 3.20N: 3.80 O: 5.53 Ne: 1.76

H-deficient componentH: 10000 He: 5000 C: 177N: 150 O: 440 Ne: 177

Model with H-deficient inclusions (0.125˝×0.167˝)[Ne II]12.8μm [Ne III]15.5μm




O++ 2p2 3P

J = 0J = 1

J = 2

J = 5/2

O+ 3d 4FJ = 9/2J = 7/2

J = 3/24

076

J = 3/2

O+ 3p 4Do

J = 7/2J = 5/2

J = 1/24

649

J = 5/2

O+ 3d 4FJ = 9/2J = 7/2

J = 3/2407

2

J = 3/2

O+ 3p 2Do

J = 5/2

451

5

Reference lineO+ 4f G[5]o

O++ level population at T

e = 1000 K, N

e = 3000 cm−3

J Actual Thermal 2 0.30 0.56 1 0.43 0.33 0 0.40 0.11

J = 9/2

J = 5/24

089 J = 11/2

J = 7/2

For direct recombinations, the upper levels of the λ4089, λ4076 and λ4649 lines can only be populated by recombinations originated from the O++ 2p2 3P

2 level, but not by those from the

3P1 level, whereas the λ4072 and λ4515 lines can be populated by recombinations from both

the 3P2 and 3P

1 levels. (Liu X-W., IAU Symp. #209, Canberra, 2001 November)

λ4072/λ4089 and λ4515/λ4089 yield apparently higher T

e's than

λ4076/λ4089 and λ4649/λ4089. O++ 2p2 3P

2 is underpopulated

compared to the thermal value.




Peimbert & Peimbert 2005, RMxAC, 23, 9Ruiz et al. 2003, ApJ, 595, 247

(Forbidden line densities)

Bastin & Storey 2005, AIP Conf. Proc., 804, p.63; Bastin & Storey 2006, Proc. IAU Symp. 234, p.369




Ab initio calculations of the O II and N II effective recombination coefficients

Calculations extend to very low electron temperatures (Te ~ 100 K)

Full dependence on the level populations of the ground states of the recombining ion DR via high-n resonances lying between the ground states of the recombining ion

Fang, Storey & Liu, 2011, A&A, 530, 18Storey 2010, private communication

Close coupling R-matrix methodin the intermediate coupling scheme

Close coupling R-matrix methodin the pair coupling scheme




Effective recombination coefficients of selected O II and N II lines as a function of electron temperature and density

McNabb et al., 2011, in preparation.Poster #




Storey 2010, private communication

Fractional intensities of O II 3p 4Do – 3s 4P (V1) as a function of density The ratio of λ4649 (J = 7/2 – 5/2) to λ4662 (J = 3/2 – 3/2) is a sensitive density diagnostic




The ratio of the O II 3p 4D7/2

o – 3s 4P5/2

λ4649 (V1) to 4fG[5]11/2

o – 3d 4F9/2

λ4089 is a sensitive temperature diagnostic

Storey 2010, private communication




Fang, Storey & Liu, 2011, A&A, 530, 18

Fractional intensities of N II 3p 3D – 3s 3Po (V3) as a function of density The ratio of λ5679 (J = 3 – 2) to λ5666 (J = 2 – 1) is a sensitive density diagnostic




Fang, Storey & Liu, 2011, A&A, 530, 18

The ratio of the N II 3p 3D3 – 3s 3P

2o λ5679 (V3) to 4f G[9/2]

5 – 3d 3F

4o λ4041

is a sensitive temperature diagnostic




Te and N

e, and associated

errors from O II linesT

e and N

e, and associated

errors from N II linesNGC 7009adf = 4.7




Te and N

e, and associated


e and N

e, and associated

errors from N II linesHf 2-2

adf = 84




Te and N

e, and associated


e and N

e, and associated

errors from N II linesM 1-42adf = 22




Te and N

e, and associated


e and N

e, and associated

errors from N II linesNGC 6153Adf = 9.2




Te and N

e, and associated


e and N

e, and associated

errors from N II linesM 42

Adf = 1.02




Simulated distributions of N II and O II line intensities in NGC 7009

McNabb et al., 2011, in preparation.Poster #




Conclusions

• New ab initio effective recombination coefficients of N II and O II recombination spectra have been calculated, extending down to temperatures as low as 100 K and taking into account the dependence on electron density of the level populations of the ground states of the recombining ions.

• Suits of temperature- and density-diagnostics based on those heavy element recombination lines have been developed.

• Applications of the above tools to PNe show that heavy element recombination lines arise from plasmas of temperatures of ∼1000 K, consistent with the expectations of the two-abundance model for high adf nebulae.




Collision strengths

H-like ionsHe+ to Zn29+: Hamada, K., et al., “Effective collision strengths for optically allowed transitions among degenerate levels of hydrogenic ions with 2⩽Z⩽30”, 2010, ADNDT, 96, 481N6+ to Na10+: Aggarwal, K. M., Keenan, F. P., Heeter, R. F., “Energy levels, radiative rates and electron impact excitation rates for transitions in H-like N VII, O VIII, F IX, Ne X and Na XI”, 2010, PhysScr, 82, 5006

He-like ionsLi+, Be2+, B3+, C4+: Aggarwal, K. M., Kato, T., Keenan, F. P., Murakami, I., “Energy Levels, Radiative Rates and Electron Impact Excitation Rates for Transitions in He-like Li II, Be III, B IV and C V”, 2011, PhysScr, 83, 5302N5+, F7+, Na9+: Aggarwal, K. M., Keenan, F. P., Heeter, R. F., “Energy levels, radiative rates and electron impact excitation rates for transitions in He-like N VI, F VIII and Na X”, 2009, PhysScr, 80, 5301N5+, Ne6+, Mg10+, Al11+, Si12+, S14+, Ca18+: Delahaye, F., Pradhan, A. K., Zeippen, C. J., "Electron Impact Excitation of Helium-like Ions up to n = 4 Levels Including Radiation Damping", 2006, JPhB, 39, 3465

Li-like ionsBe+ to Kr33+: Liang, G. Y., Badnell, N. R., "R-Matrix Electron-Impact Excitation Data for the Li-like Iso-Electronic Sequence Including Auger and Radiation Damping", 2011, A&A, 528, A69N4+, F6+, Ne7+, Na8+: Aggarwal, K. M., Keenan, F. P., Heeter, R. F., “Energy Levels, Radiative Rates and Electron Impact Excitation Rates for Transitions in Li-like N V, F VII, Ne VIII and Na IX”, 2010, PhysScr, 81, 5303

Be-like ionsMg8+: Hudson, C. E., "Breit-Pauli R-Matrix Calculation for Fine Structure Effective Collision Strengths from Electron Impact Excitation of Mg IX”, 2009, A&A, 493, 697C2+, N3+, O4+: Fogle, M., et al.,“Electron-Impact Ionization of Be-like C III, N IV, and O V”, 2008, ApJS, 175, 543Ar14+: Bhatia, A. K., Landi, E., “Atomic data and spectral line intensities for Ar XV”, 2008, ADNDT, 94, 223

B-like ionsC+: Tayal, S. S., "Electron Impact Excitation Collision Strength for Transitions in C II", 2008, A&A, 486, 629; Tayal, S. S., "Electron Impact Excitation Collision Strength for Transitions in C II", 2009, A&A, 501, 381O3+: Keenan, F. P., et al., “Ultraviolet and extreme-ultraviolet line ratio diagnostics for O IV”, 2009, A&A, 495, 359

Dirac Atomic R-matrix Code (DARC)Flexible Atomic Code (FAC): Non-resonanceMost important at low Te's




Collision strengths

C-like ionsN+: Tayal, S. S., “Electron Excitation Collision Strengths for Singly Ionized Nitrogen”, 2011, ApJS, 195, 11

N-like ionsN0: Tayal, S. S., "New Accurate Oscillator Strengths and Electron Excitation Collision Strengths for N I", 2006, ApJS, 163, 207O+: Tayal, S. S., “Oscillator Strengths and Electron Collision Rates for Fine-Structure Transitions in O II”, 2007, ApJS, 171, 331; Tayal, S. S., “Electron impact excitation of forbidden and allowed transitions in O II”, 2006, J.Phys.B, 39, 4393; Montenegro, M., Eissner, W., Nahar, S. N., Pradhan, A. K., "Relativistic and Correlation Effects in Electron Impact Excitation of Forbidden Transitions of O II", 2006, JPhB, 39, 1863; Pradhan, A. K., Montenegro, M., Nahar, S. N., Eissner, W., "[O II] Line Ratios", 2006, MNRAS, 366, L6

O-like ionsMg4+: Hudson, C. E., Ramsbottom, C. A., Norrington, P. H., Scott, M. P., "Breit-Pauli R-Matrix Calculation of Fine Structure Effective Collision Strengths for the Electron Impact Excitation of Mg V", 2009, A&A, 494, 729

F-like ionsNe+ to Kr27+: Witthoeft, M. C., Whiteford, A. D., Badnell, N. R., "R-Matrix Electron-Impact Excitation Calculations along the F-like Iso-Electronic Sequence", 2007, JPhB, 40, 2969Kr27+: Aggarwal, K. M., Keenan, F. P., Lawson, K. D., “Electron impact excitation of Kr XXVIII”, 2011, ADNDT, 97, 225

Ne-like ionsNi18+: Aggarwal, K. M., Keenan, F. P., "Effective Collision Strengths for Transitions in Ni XIX", 2008, A&A, 488, 365Na+ to Kr26+: Liang, G. Y., Badnell, N. R., “R-Matrix Electron-Impact Excitation Data for the Ne-like Iso-Electronic Sequence”, 2010, A&A, 518, A64




Collision strengths

Na-like ionsMg+ to Kr25+: Liang, G. Y., Whiteford, A. D., Badnell, N. R., "R-Matrix Electron-Impact Excitation Data for the Na-like Iso-Electronic Sequence", 2009, A&A, 500, 1263

Mg-like ionsFe14+: Norrington, P. H., Hudson, C. E., “Effective Collision Strengths for Mg-like Iron Peak Ions”, 2009, JPhCS, 163, 2033

Al-like ionsSi+: Bautista, M. A., et al., "Radiative Transfer Rates and Collision Strengths for Si II", 2009, A&A, 508, 1527

P-like ionsS+: Tayal, S. S. and Zatsarinny, O., "Breit-Pauli Transition Probabilities and Electron Excitation Collision Strengths for Singly Ionized Sulfur", 2010, ApJS, 188, 32

S-like ionsAr2+: Munoz Burgos, J. M., Loch, S. D., Ballance, C. P., Boivin, R. F., "Electron-Impact Excitation of Ar2+", 2009, A&A, 500, 1253

Ar-like ionsK+: Tayal, S. S., Zatsarinny, O., "Electron Excitation Collision Strengths for Transitions in K II", 2010, A&A, 510, A79Ni10+: Verma, N., Jha, A. K. S., Mohan, M., “Electron Collisional Excitation of Argon-like Ni XI using the Breit-Pauli R-Matrix Method”, 2007, EurPhysJ, 42, 235

K-like ions Ca+: Meléndez, M., Bautista, M. A., Badnell, N. R., “Atomic data from the IRON project⋆ LXIV. Radiative transition rates and collision strengths for Ca II”, 2007, A&A, 469, 1203




Collision strengths

Iron-peak ionsCr+: Wasson, I. R., Ramsbottom, C. A., Norrington, P. H., "Electron-Impact Excitation of Cr II A Theoretical Calculation of Collision and Effective Collision Strengths for Forbidden Transitions", 2010, A&A, 524, A35Ni+: Cassidy, C. M., Ramsbottom, C. A., Scott, M. P., Burke, P. G., "Electron-Impact Excitation of Ni II Collision Strengths and Effective Collision Strengths for Low-Lying Fine-Structure Forbidden Transitions", 2010, A&A, 513, A55Fe0, Fe1+, Fe15+, Fe16+: Montenegro, M., et al., “The Iron Project And The RMAX Project: Radiative and Collisional Processes of Iron Ions - Fe I, Fe II, Fe XVI, Fe XVII”, 2008, APS DMP, L2056Fe2+: Bautista, M. A., Balance, C. P., Quinet, P., "Atomic Data and Spectral Model for Fe III", 2010, ApJL, 718, L189Fe6+: Witthoeft, M. C., Badnell, N. R., "Atomic data from the IRON Project. LXV. Electron-impact excitation of Fe6+", 2008, A&A, 481, 543Fe10+: Del Zanna, G., Storey, P. J., Mason, H. E., “Atomic data from the IRON project. LXVIII. Electron impact excitation of Fe xi”, 2010, A&A, 514, A40Fe12+: Storey, P. J., Zeippen, C. J., “Atomic data from the IRON project. LXVII. Electron impact excitation of Fe XIII”, 2010, A&A, 511, A78Fe14+, Fe15+: Montenegro, M., et al., “The Iron Project and the RMAX Project: Transitions in Fe XV, Fe XVI, and Astrophysical Applications”, 2007, APS DMP, D1060Fe17+: Nahar, S. N., “Atomic data from the Iron Project. LXII. Allowed and forbidden transitions in Fe XVIII in relativistic Breit-Pauli approximation”, 2006, A&A, 457, 721; Witthoeft, M. C., et al., “Atomic data from the IRON project. LX. Electron-impact excitation of n = 3, 4 levels of Fe17+”, 2006, A&A, 446, 361Fe18+: Butler, K., Badnell, N. R., “Atomic data from the IRON project. LXVI. Electron impact excitation of Fe18+”, 2008, A&A, 489, 1369Fe19+: Witthoeft, M. C., Del Zanna, G., Badnell, N. R., “Atomic data from the IRON project. LXIII. Electron-impact excitation of Fe19+ up to n = 4”, 2007, A&A, 466, 763Fe16+ to Fe22+: Landi, E., and Gu, M. F., “Atomic Data For High-Energy Configurations In Fe xvii–xxiii”, 2006, ApJ, 640, 1171

OthersSi11+, Si12+, Si13+: Aggarwal, K. M., Keenan, F. P., “Energy levels, radiative rates and electron impact excitation rates for transitions in Si XII, Si XIII and Si XIV”, 2010, PhysScr, 82, 5302




He-like (recombined) ionsNe IX: Nahar, S. N., Pradhan, A. K.,“Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. X. Ne VIII and Ne IX for ultraviolet and X-ray modeling”, ApJS, 2006, 162, 417N VI, F VIII: Nahar, S. N., “Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. XI. N V–VI and F VII–VIII for ultraviolet and X-ray modeling”, 2006, ApJS, 164, 280Na X, Mg XI: Nahar, S. N., “Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. XII. Na IX, Na X, Mg X, and Mg XI for ultraviolet and X-ray modeling”, 2006, ApJS, 167, 315Total 32 ions, from He I to Zn XXIX, plus Kr XXXV, Mo XXXXI and Xe XXXXXIII: Badnell, N. R., “Dielectronic recombination data for dynamic finite-density plasmas X. The hydrogen isoelectronic sequence”, 2006, A&A, 447, 389

Li-like (recombined) ionsNe VIII: Nahar, S. N., Pradhan, A. K.,“Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. X. Ne VIII and Ne IX for ultraviolet and X-ray modeling”, ApJS, 2006, 162, 417N V, F VII: Nahar, S. N., “Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. XI. N V–VI and F VII–VIII for ultraviolet and X-ray modeling”, 2006, ApJS, 164, 280Na IX, Mg X: Nahar, S. N., “Electron-ion recombination rate coefficients and photoionization cross sections for astrophysically abundant elements. XII. Na IX, Na X, Mg X, and Mg XI for ultraviolet and X-ray modeling”, 2006, ApJS, 167, 315Li – Ni, Zn, Kr, Mo, and Xe: Bautista, M. A., Badnell, N. R., “Dielectronic recombination data for dynamic finite-density plasmas XII. The helium isoelectronic sequence”, 2007, A&A, 466, 755

Radiative and di-electronic recombination rates




Ne-like (recombined) ionsFrom Ne I to Zn XXI, as well as for Kr XXVII, Mo XXXIII, and Xe XXXXV: Zatsarinny, O., et al., “Dielectronic recombination data for dynamic finite-density plasmas IX. The fluorine isoelectronic sequence”, 2006, A&A, 447, 379

Mg-like (recombined) ionsTotal 22 ions, from Mg I to Zn XIX, as well as Kr XXV, Mo XXXI, and Xe XXXXIII: Altun, Z., et al. “Dielectronic recombination data for dynamic finite-density plasmas XI. The sodium isoelectronic sequence”, 2007, A&A, 447, 1165Ca IX to Zn XIX: Kwon, D. H., Savin, D. W., “Effects of Configuration Interaction for Dielectronic Recombination of Na-like Ions Forming Mg-like Ions”, 2011, ApJ, 734, 2

Al-like (recombined) ionsFe XIV: Lukic D. V., et al., “Dielectronic recombination of Fe XV forming Fe XIV: Laboratory measurements and theoretical calculations”, 2007, ApJ, 664, 1244

K-like (recombined) ionsFrom KI to Zn XII: Nikolic, D., et al, “Dielectronic recombination of argon-like ions”, 2010, A&A, 516, 97

Iron (recombined) ionsFe VIII – Fe XII: Badnell, N. R., “Dielectronic recombination of Fe 3pq ions: A key ingredient for describing X-ray absorption in active galactic nuclei”, 2006, ApJ, 651, L73Fe XIII: Badnell, N. R., “Dielectronic recombination of Fe13+: benchmarking the M-shell”, 2006, JphB, 39, 4825Fe XXII: Savin, D. W., et al, “Dielectronic recombination of Fe XXIII forming Fe XXII: Laboratory measurements and theoretical calculations”, 2006, ApJ, 642, 1275

Neutron-capture (recombined) ionsSe I – Se VI: Sterling, N. C., Witthoeft, M. C., “Atomic data for neutron-capture elements. I. Photoionization and recombination properties of low charge selenium ions”, 2011, A&A, 529A, 147Kr I – Kr VI: Sterling, N. C., “Atomic data for neutron-capture elements II. Photoionization and recombination properties of low-charge krypton ions”, arXiv:1107.3843

Di-electronic recombination rates




Radiative rates

H-like ionsN6+ to Na10+: Aggarwal, K. M., Keenan, F. P., Heeter, R. F., “Energy levels, radiative rates and electron impact excitation rates for transitions in H-like N VII, O VIII, F IX, Ne X and Na XI”, 2010, PhysScr, 82, 5006Si13+: Aggarwal, K. M., Keenan, F. P., “Energy levels, radiative rates and electron impact excitation rates for transitions in Si XII, Si XIII and Si XIV”, 2010, PhysScr, 82, 5302

He-like ionsN5+, Ne6+, Mg10+, Al11+, Si12+, S14+, Ca18+: Delahaye, F., Pradhan, A. K., Zeippen, C. J., “Electron Impact Excitation of Helium-like Ions up to n = 4 Levels Including Radiation Damping”, 2006, JPhB, 39, 3465Li+, Be2+, B3+, C4+: Aggarwal, K. M., Kato, T., Keenan, F. P., Murakami, I., “Energy Levels, Radiative Rates and Electron Impact Excitation Rates for Transitions in He-like Li II, Be III, B IV and C V”, 2011, PhysScr, 83, 5302Si12+: Aggarwal, K. M., Keenan, F. P., “Energy levels, radiative rates and electron impact excitation rates for transitions in Si XII, Si XIII and Si XIV”, 2010, PhysScr, 82, 5302

Li-like ionsN4+, F6+, Ne7+, Na8+: Aggarwal, K. M., Keenan, F. P., Heeter, R. F., “Energy Levels, Radiative Rates and Electron Impact Excitation Rates for Transitions in Li-like N V, F VII, Ne VIII and Na IX”, 2010, PhysScr, 81, 5303Be+ to Kr33+: Liang, G. Y., Badnell, N. R., “R-Matrix Electron-Impact Excitation Data for the Li-like Iso-Electronic Sequence Including Auger and Radiation Damping”, 2011, A&A, 528, A69Si11+: Aggarwal, K. M., Keenan, F. P., “Energy levels, radiative rates and electron impact excitation rates for transitions in Si XII, Si XIII and Si XIV”, 2010, PhysScr, 82, 5302

Be-like ionsC2+, N3+, O4+: Fogle, M., et al.,“Electron-Impact Ionization of Be-like C III, N IV, and O V”, 2008, ApJS, 175, 543Ar14+: Bhatia, A. K., Landi, E., “Atomic data and spectral line intensities for Ar XV”, 2008, ADNDT, 94, 223Mg8+: Zanna, G. D., Rozum, I., and Badnell, N. R., “Electron-impact excitation of Be-like Mg”, 2008, A&A, 487, 1023; Hudson, C. E., "Breit-Pauli R-Matrix Calculation for Fine Structure Effective Collision Strengths from Electron Impact Excitation of Mg IX”, 2009, A&A, 493, 697




Radiative rates

B-like ionsC+: Wiese, W. L., Fuhr, J. R., “New Critical Compilations of Atomic Transition Probabilities for Neutral and Singly Ionized Carbon, Nitrogen, and Iron”, 2006, NLA Conf. 278 S., "Electron Impact Excitation Collision Strength for Transitions in C II", 2008, A&A, 486, 629; Tayal, S. S., "Electron Impact Excitation Collision Strength for Transitions in C II", 2009, A&A, 501, 381O3+: Aggarwal, K.M., Keenan, F. P., ”Energy levels, radiative rates, and excitation rates for transitions in O IV”, 2008, A&A, 486, 1053

C-like ionsC0: Wiese, W. L., Fuhr, J. R., “New Critical Compilations of Atomic Transition Probabilities for Neutral and Singly Ionized Carbon, Nitrogen, and Iron”, 2006, NLA Conf. 278N+: Wiese, W. L., Fuhr, J. R., “New Critical Compilations of Atomic Transition Probabilities for Neutral and Singly Ionized Carbon, Nitrogen, and Iron”, 2006, NLA Conf. 278; Fang, X., Storey, P. J., Liu, X. -W., “New effective recombination coefficients for nebular N II lines⋆”, 2011, A&A, 530, A18

N-like ionsN0: Tayal, S. S., "New Accurate Oscillator Strengths and Electron Excitation Collision Strengths for N I", 2006, ApJS, 163, 207; Wiese, W. L., Fuhr, J. R., “New Critical Compilations of Atomic Transition Probabilities for Neutral and Singly Ionized Carbon, Nitrogen, and Iron”, 2006, NLA Conf. 278O+: Montenegro, M., Eissner, W., Nahar, S. N., Pradhan, A. K., "Relativistic and Correlation Effects in Electron Impact Excitation of Forbidden Transitions of O II", 2006, JPhB, 39, 1863; Tayal, S. S., “Oscillator Strengths and Electron Collision Rates for Fine-Structure Transitions in O II”, 2007, ApJS, 171, 331

F-like ionsNe+ to Kr27+: Witthoeft, M. C., Whiteford, A. D., Badnell, N. R., "R-Matrix Electron-Impact Excitation Calculations along the F-like Iso-Electronic Sequence", 2007, JPhB, 40, 2969




Radiative rates

Ne-like ionsNa+ to Kr26+: Liang, G. Y., Badnell, N. R., “R-Matrix Electron-Impact Excitation Data for the Ne-like Iso-Electronic Sequence”, 2010, A&A, 518, A64

Na-like ionsMg+ to Kr25+: Liang, G. Y., Whiteford, A. D., Badnell, N. R., “R-Matrix Electron-Impact Excitation Data for the Na-like Iso-Electronic Sequence”, 2009, A&A, 500, 1263

Al-like ionsSi+: Bautista, M. A., et al., “Radiative Transfer Rates and Collision Strengths for Si II”, 2009, A&A, 508, 1527

P-like ionsS+: Tayal, S. S., Zatsarinny, O., “Breit-Pauli Transition Probabilities and Electron Excitation Collision Strengths for Singly Ionized Sulfur”, 2010, ApJS, 188, 32

Ar-like ionsK+: Tayal, S. S., Zatsarinny, O., “Electron Excitation Collision Strengths for Transitions in K II”, 2010, A&A, 510, A79Ni10+: Verma, N., Jha, A. K. S., Mohan, M., “Electron Collisional Excitation of Argon-like Ni XI using the Breit-Pauli R-Matrix Method”, 2007, EurPhysJ, 42, 235

K-like ions Ca+: Meléndez, M., Bautista, M. A., Badnell, N. R., “Atomic data from the IRON project⋆ LXIV. Radiative transition rates and collision strengths for Ca II”, 2007, A&A, 469, 1203

K-Vacancy Ne, Mg, Si, S, Ar, Ca: Palmeri, P., et al., “Radiative and Auger Decay of K-Vacancy Levels in the Ne, Mg, Si, S, Ar, and Ca Isonuclear Sequences”, 2008, ApJ, 177, 408Be+ to Zn27+: Gorczyca, T.W., et al., “Importance of Configuration Interaction For Accurate Atomic Data: Fluorescence Yields of K-Shell Vacancy, Lithium-Like Ions”, 2006, ApJ, 638, L121




Radiative rates

Iron-peak ionsSc+: Bautista, M. A., et al., “Scandium and chromium in the strontium filament in the Homunculus of η Carinae”, 2009, MNRAS, 1503, 1512Cr+: Bautista, M. A., et al., “Scandium and chromium in the strontium filament in the Homunculus of η Carinae”, 2009, MNRAS, 1503, 1512; Wasson, I. R., Ramsbottom, C. A., Norrington, P. H., "Electron-Impact Excitation of Cr II A Theoretical Calculation of Collision and Effective Collision Strengths for Forbidden Transitions", 2010, A&A, 524, A35Fe0, Fe+: Wiese, W. L., Fuhr, J. R., “New Critical Compilations of Atomic Transition Probabilities for Neutral and Singly Ionized Carbon, Nitrogen, and Iron”, 2006, NLA Conf. 278Fe2+: Bautista, M. A., Ballance, C. P., Quinet, P., “Atomic Data and Spectral Model For Fe III”, 2010, ApJL, 718, L189Fe3+: Nahar, S. N., “Atomic data from the iron project LXI. Radiative E1, E2, E3, and M1 transition probabilities for Fe IV⋆”, 2006, A&A, 448, 779Fe6+: Witthoeft, M. C., Badnell, N. R., “Atomic data from the IRON Project LXV. Electron-impact excitation of Fe6+”, 2008, A&A, 481, 543Fe13+: Liang, G. Y., et al., “R-matrix Electron-Impact Excitation of Fe13+ and its Application To the Soft X-ray and Extreme-Ultraviolet Spectroscopy of Corona-Like Plasmas”, 2010, ApJS, 190, 322Fe15+: Liang, G. Y., Whiteford, A. D., and Badnell, N. R., “R-matrix inner-shell electron-impact excitation of Fe15+ including Auger-plus-radiation damping”, 2008, JPhB, 41, 5203Fe17+: Witthoeft, M. C., et al., “Atomic data from the IRON project LX. Electron-impact excitation of n = 3, 4 levels of Fe17+”, 2006, A&A, 446, 361; Nahar, S. N., “Atomic data from the Iron Project⋆ LXII. Allowed and forbidden transitions in Fe XVIII in relativistic Breit-Pauli approximation”, 2006, A&A, 457, 721Fe18+: Butler, K., Badnell, N. R., “Atomic data from the IRON project LXVI. Electron impact excitation of Fe18+⋆”, 2008, A&A, 489, 1369Fe19+: Witthoeft, M. C., Zanna, G. Del, and Badnell, N. R., “Atomic data from the IRON project⋆ LXIII. Electron-impact excitation of Fe19+ up to n = 4”, 2007, A&A, 466, 763Fe16+ to Fe22+: Landi, E., and Gu, M. F., “Atomic Data For High-Energy Configurations In Fe xvii–xxiii”, 2006, ApJ, 640, 1171Ni+ to Ni27+: Palmeri, P., et al., “Radiative and Auger Decay Data For Modeling Nickel K Lines”, 2008, ApJ, 179, 542



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