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Home All issues Volume 496 / No 2 (March III 2009) A&A, 496 2 (2009) 365-374 Full HTML
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Table 2:

Reactions and rate coefficients adopted in the chemical model.
Cosmic rays ionization Rate in s-1, with $\zeta$ the rate of cosmic ray ionization of H2. Ref.
H + CR $\rightarrow$ H+ + e 0.46$\zeta$ c
D + CR $\rightarrow$ H+ + e 0.46$\zeta$ c
H2 + CR $\rightarrow$ H + H 1.5$\zeta$ c
H2 + CR $\rightarrow$ H2+ + e 0.96$\zeta$ c
HD + CR $\rightarrow$ H + D 1.5$\zeta$ c
HD + CR $\rightarrow$ HD+ + e 0.96$\zeta$ c
D2 + CR $\rightarrow$ D + D 1.5$\zeta$ c
Reaction Rate in cm3 s-1 Ref.
H2 + D $\rightarrow$ H + HD dex $(-56.4737+5.88886\times \log({\rm Tg})+7.196292\times \log({\rm Tg})^2+2.25069\times \log({\rm Tg})^3-2.16903\times \log({\rm Tg})^4$ a
  $+0.317887\times \log({\rm Tg})^5$  
HD + H $\rightarrow$ H2 + D $5.25\times 10^{-11}\times \exp(-4430/{\rm Tg})$ if Tg < 200 K  
  $5.25\times 10^{-11}\times \exp((-4430/{\rm Tg})+(173~900/{\rm Tg}^2))$ if Tg >200 K a
D+ + H2 $\rightarrow$ H+ + HD $10^{-9}\times (0.417+0.846\times \log({\rm Tg})-0.137\times \log({\rm Tg})^2$ a
H+ + HD $\rightarrow$ D+ + H2 $1.1\times 10^{-9} \times \exp{-488/{\rm Tg}}$ a
H+ + D $\rightarrow$ D+ + H $2\times 10^{-10}\times {\rm Tg}^{0.402}\times \exp{-37.1/{\rm Tg}}-3.31\times 10^{-17}\times {\rm Tg}^{1.48}$ a
H + D+ $\rightarrow$ H+ + D $2.06\times 10^{-10}\times {\rm Tg}^{0.396} \times \exp{-33/{\rm Tg}}+2.03\times 10^{-9}\times {\rm Tg}^{-0.332}$ a
HD + D+ $\rightarrow$ D2 + H+ $1\times 10^{-9}$ a
H+ + D2 $\rightarrow$ D+ + HD $2.1\times 10^{-9}\times \exp{-491/{\rm Tg}}$ a
H2 + H+ $\rightarrow$ H2+ + H $\exp(-21237.15/{\rm Tg})\times (3.3232183\times 10^{-7}+3.3735382\times 10^{-7}\times \ln({\rm Tg})-1.4491368\times 10^{-7}\times \ln({\rm Tg})^2$  
  $+3.4172805\times 10^{-8}\times \ln({\rm Tg})^3-4.7813720\times 10^{-9}\times \ln({\rm Tg})^4+3.9731542\times 10^{-10}\times \ln({\rm Tg})^5$  
  $-1.8171411\times 10^{-11}\times \ln({\rm Tg})^6+3.5311932\times 10^{-13}\times \ln({\rm Tg})^7$ b
H + H+ $\rightarrow$ H2+ + phot dex $(-19.38-1.523\times \log({\rm Tg})+1.118\times (\log({\rm Tg}))^2-0.1269\times (\log({\rm Tg})^3))$ a
H + H2+ $\rightarrow$ H2 + H+ 6.4 $\times $ 10-10 a
H + HD+ $\rightarrow$ H2 + D+ 1 $\times $ 10-9 a
H+ + e $\rightarrow$ H + phot 2.753  $\times 10^{-14} \times (315614/{\rm Tg})^{1.5}\times (1+(115188/{\rm Tg})^{0.407})^{-2.242}$ b, caseB
D+ + e $\rightarrow$ D+ phot 2.753  $\times 10^{-14} \times (315614/{\rm Tg})^{1.5}\times (1+(115188/{\rm Tg})^{0.407})^{-2.242}$ b, case B
H2+ + e $\rightarrow$ H + H 10-8 if Tg < 617 K  
  1.32 $^{-6}\times {\rm Tg}^{-0.76}$ if Tg > 617 K a
HD+ + e $\rightarrow$H + D 7.2  $\times 10^{-8}\times {\rm Tg}^{-0.5}$ a
H + e $\rightarrow$ H- + phot dex $(-17.845+0.762\times \log({\rm Tg}+0.1523 \times (\log({\rm Tg}))^2-0.03274 \times \log({\rm Tg})^3)$ a
D + e $\rightarrow$ D- + phot dex $(-17.845+0.762 \times \log({\rm Tg})+0.1523 \times (\log({\rm Tg}))^2-0.03274 \times \log({\rm Tg})^3)$ a
H + e $\rightarrow$ H+ + e + e $\exp(-3.271396\times 10+1.3536\times 10\times \ln({\rm Te})-5.7393\times \ln({\rm Te})^2+1.5631\times \ln({\rm Te})^3)$ a
D + e $\rightarrow$ D+ + e + e $\exp(-3.271396\times 10+1.3536\times 10\times \ln({\rm Te})-5.7393\times \ln({\rm Te})^2+1.5631\times \ln({\rm Te})^3)$ a
H- + H $\rightarrow$ H2 + e (higher value) $5\times 10^{-9} $ b
H- + H $\rightarrow$ H2 + e (lower value) $0.65\times 10^{-9}$ b
D- + H $\rightarrow$ HD + e(higher value) $0.5 \times 5\times 10^{-9}$ b
D- + H $\rightarrow$ HD + e(lower value) $0.5 \times 0.65\times 10^{-9}$ b
H- + D $\rightarrow$ HD + e(higher value) $0.5 \times 5\times 10^{-9}$ b
H- + D $\rightarrow$ HD + e(lower value) $0.5 \times 0.65\times 10^{-9}$ b
D- + D $\rightarrow$ D2 + e (higher value) $5\times 10^{-9} $ b
D- + D $\rightarrow$ D2 + e (lower value) $0.65\times 10^{-9}$ b
H+ + D- $\rightarrow$ HD+ + e $1.1\times 10^{9}\times ({\rm Tg}/300)^{-0.4}$ a
D+ + H- $\rightarrow$ HD+ + e $1.1\times 10^{9}\times ({\rm Tg}/300)^{-0.4}$ a

a Glover & Savin (2008); b Abel & Glover (2008); c Walmsley et al. 2004.


Source LaTeX | All tables | In the text

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