SOURCES OF DATA FOR THERMAL COLLISION STRENGTHS

Where data is not available, the following treatment is used

* Regemorter's formula for allowed transitions (taken as f_osc > 1E-3)

* Axelrod's formula for others (Upsilon = 0.004*g1*g2)

* A few special treatments for l-changing transitions (see below)

HI

Anderson 2000 for n-changing transitions with nmax ⇐ 5. (J11)

Johnson 1972 for n-changing transitions with nmax >= 6. (J11)

Pengelly & Seaton 1964 for l-changing transitions (same n). (reference missing in J11)

He I

Almog & Netzer 1989 (covers all).

He II

Generic formula (just 1 transition).

C I

Pradhan table, first 6 levels (covers all important cooling transitions). Rest generic formula.

C II

Pradhan table, first 5 levels (covers all important cooling transitions). Rest generic formula.

C III

Single transition, Pradhan table.

N I

Pradhan table, first 5 levels (covers all important cooling transitions). Rest generic formula.

N II

Pradhan table, first 6 levels (covers all important cooling transitions). Rest generic formula.

N III

Not included.

O I

Pradhan table, first 7 levels (covers all important cooling transitions). Rest generic formula.

O II

Pradhan table, first 5 levels (covers all important cooling transitions). Rest generic formula.

O III

Not included.

NeI

Generic formula. Energy gaps are too large for thermal cooling.

Ne II

Pradhan table.

Na I

Park 1971, first 13 levels. Ref is J15a

Na II

1 transition, generic formula.

MgI

Mauas 1988 (first 21 levels (to s4d 3D), at 5000 K + power law fits) for n-hanging collisions

For l-changing collisions (same n) Upsilon = 100*g1*g2 is used (up to s4d 3D) (large Upsilon values are indicated in Sundqvist 2008)

Mg II

Pradhan online, 2 transitions (2795 and 2802 A). Value at 5000 K. Rest generic.

Si I

Generic formula.

Si II

Pradhan table, first 5 levels (covers most important cooling transitions).

S I

Generic formula.

S II

Pradhan table, all with GS, at 10,000 K.

Ar I

1 UV transiton, generic formula.

Ar II

1 transition (6.98 mu), Pradhan table 2 at 5000 K.

Ca I

Generic formula.

Ca II

Melendez+2007, first 10 levels, at 3000 K.

Sc-Mn

Generic formula.

Fe I

Pelan & Berrington 1997, first 10 levels, 4000 K. Axelrod for rest.

Fe II

Zhang & Pradhan 1995 (partially covers first 372 levels) (J11). Values are presented at 5000, 10000, 20000 and 50000 K, we use the ones at 5000 K.

Fe III

Zhang & Pradhan 1995b (J15a) data for 6 first multiplets (17 levels). Values are presented at 10000 and 20000 K, we use the ones at 10000 K. In J12 and J14 generic formula used.

Co I

Generic formula.

Co II

Generic formula.

Ni I

Generic formula.

Ni II

Cassidy 2010, 2011 (J12). Covers 74 lowest levels (with some gaps), up to 79923 cm^-1. There are tables over T available, however I have only coded in the values at 5000 K. Inspection of the tables show slow variation for vast majority of transitions within 10^3 - 10^4 K so should be fine.