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This notebook was generated on \ 07/13-15/01.\ \>", "Text"] }, Open ]], Cell[CellGroupData[{ Cell["Setup notebook enviroment ", "SmallText", PageWidth->Infinity], Cell[BoxData[ \(\(a = 1;\)\)], "Input"], Cell[BoxData[ \(\(\(ClearAll["\"];\)\(\ \)\)\)], "Input", PageWidth->Infinity, Evaluatable->True], Cell[BoxData[ \(\(\(Remove["\"];\)\(\ \)\)\)], "Input", PageWidth->Infinity, Evaluatable->True], Cell[BoxData[ \(\(startclock\ = \ SessionTime[];\)\)], "Input", PageWidth->Infinity, Evaluatable->True], Cell[BoxData[ \(\(Off[General::spell];\)\)], "Input", PageWidth->Infinity, Evaluatable->True], Cell[BoxData[ \(\(Off[General::spell1];\)\)], "Input", PageWidth->Infinity, Evaluatable->True], Cell[BoxData[ \(Needs["\"]\)], "Input", PageWidth->Infinity, Evaluatable->True], Cell[BoxData[ \(Needs["\"]\)], "Input"], Cell[BoxData[ \(now\ := \ StringForm["\<``/``/`` ``:``:``\>", \(Date[]\)[\([2]\)], \ \(Date[]\)[\([3]\)], \(Date[]\)[\([1]\)], \(Date[]\)[\([4]\)], \ \(Date[]\)[\([5]\)], \(Date[]\)[\([6]\)]]\)], "Input"] }, Closed]], Cell[BoxData[ \(now\)], "Input"], Cell[BoxData[ \(SetDirectory["\"]\)], "Input"], Cell[BoxData[ \(\(\(\ \)\(plotColors\ = \ {\[IndentingNewLine] (*1 - red*) \ {Hue[ 0.0], Thickness[0.007], Dashing[{}]}, \[IndentingNewLine] (*2 - orange*) \ {Hue[0.1], Thickness[0.007], Dashing[{}]}, \[IndentingNewLine] (*3 - green*) \ {Hue[0.3], Thickness[0.007], Dashing[{}]}, \[IndentingNewLine] (*4 - cyan*) \ {Hue[0.5], Thickness[0.007], Dashing[{}]}, \[IndentingNewLine] (*5 - dk\ blue*) \ {Hue[0.7], Thickness[0.007], Dashing[{}]}, \[IndentingNewLine] (*6 - purple*) {Hue[0.8], Thickness[0.007], Dashing[{}]}, \[IndentingNewLine] (*7 - black*) {Thickness[ 0.007], Dashing[{}]}, \[IndentingNewLine] (*8 - dash\ red*) {Hue[0.0], Thickness[0.007], Dashing[{0.05, 0.05}]}, \[IndentingNewLine] (*9 - dash\ orange*) {Hue[0.1], Thickness[0.007], Dashing[{0.05, 0.05}]}, (*10 - dash\ green*) {Hue[0.3], Thickness[0.007], Dashing[{0.05, 0.05}]}, \[IndentingNewLine] (*11 - dash\ cyan*) {Hue[0.5], Thickness[0.007], Dashing[{0.05, 0.05}]}, \[IndentingNewLine] (*12 - dash\ dk\ blue*) {Hue[0.7], Thickness[0.007], Dashing[{0.05, 0.05}]}, \[IndentingNewLine] (*13 - dash\ purple*) {Hue[0.8], Thickness[0.007], Dashing[{0.05, 0.05}]}, \[IndentingNewLine] (*14 - dash\ black*) {Thickness[0.007], Dashing[{0.02, 0.02}]}};\)\)\)], "Input"], Cell[BoxData[ \(Clear[enrel]\)], "Input"], Cell["Cross sections", "Section"], Cell["\<\ Here the cross sections are in units of 10E-20 m^2 and energies are in eV.\ \>", "Text"], Cell["H+ Collisions with Ar.", "Subsection"], Cell["\<\ Momentum transfer cross section is based on Krstic and Schulz (2001). There \ appears to be no mobility data for H+ in Ar. One could estimate it from the \ Langevin mobility formula in McDaniel (1964) or McDaniel and Mason (1973). \ \>", "Text"], Cell[BoxData[ \(qmHpArLangevin\ := 21.6*\((41/40*enlab)\)^\((\(-0.5\))\)*\ \((1 + enlab/56)\)^\((\(-1.5\))\) + 1. *10^\(-30\)\ //. \ enlab\ -> \ 41/40*enrel\)], "Input"], Cell["\<\ Krstic and Schulz (2001) calculated of elastic scattering for H+ + Ar as \ listed below with cross sections in a.u. versus collision energy (in CM) in \ eV:\ \>", "Text"], Cell[BoxData[ \(\(krsticTable\ = \ Transpose[ Drop[Import["\", "\"], 4]];\)\)], "Input"], Cell[BoxData[ \(\(qmHpArKrsticTable\ = \ Transpose[{krsticTable[\([1]\)], \((0.529)\)^2* krsticTable[\([3]\)]}];\)\)], "Input"], Cell[BoxData[ \(\(qmHpArKrsticPlot\ = \ LogLogListPlot[qmHpArKrsticTable, \ PlotRange -> {{0.01, 1000. }, {0.01, 1000}}, PlotStyle -> PointSize[0.02], GridLines\ -> \ True, ImageSize\ -> 432, \ DisplayFunction\ -> \ Identity];\)\)], "Input"], Cell["\<\ A fit to the theoretical results of Krsitc and Schultz (2001) from the Web \ is:\ \>", "Text"], Cell[BoxData[ \(qmHpAr := 21.6*\((enrel)\)^\((\(-0.5\))\)*\ \((1 + \((enrel/ 0.7)\)^1.2)\)^\((0.5)\)/\((1 + \((enrel/ 2.2)\)^4.2)\)^0.4*\((1 + \((enrel/ 9. )\)^2.3)\)^0.45/\((1 + \((enrel/ 300. )\)^2. )\)^0.5 + 1. *10^\(\(-30\)\(\ \)\)\)], "Input"], Cell["\<\ H+ + Ar -> Ar+ + H This charge transfer has been measured by a number of people; Stedeford and \ Hasted (1954), Williams et al (1966), Koopman (1967), Maier (1978), and \ Johnson (1989). The threshold in CM is 15.75 - 13.6 = 2.15 eV. Charge \ transfer in collisions like this often take place at large enough radii so \ the there is no change in particle velocities during charge transfer. A \ smooth curve through their data is:\ \>", "Text"], Cell[BoxData[ \(qctHpAr\ := \ UnitStep[enlab - 41/40*2.15]*\(+1.7\)*10^\(-14\)*\((enlab - 2.15)\)^8.5/\((1 + 0.6*\((enlab/50)\)^0.5 + \((enlab/105)\))\)^9.5\ + \ 1. *10^\(-30\)\ //. \ enlab\ -> \ 41/40*enrel\)], "Input"], Cell["\<\ H+ + Ar -> Ar+ + H+ + e Ionization has is given by Rudd et al (1985). The threshold in CM is 15.75 \ eV. A smooth curve through their data for energies up to 10 keV is:\ \>", "Text"], Cell[BoxData[ \(qiHpAr\ := \ UnitStep[enlab - 41/40*15.75]*1.06*10^\(-3\)*\((enlab - 41/40*15.75)\)^ .85\ + \ 1. *10^\(-30\)\ //. \[IndentingNewLine]\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ enlab\ -> \ 41/40*enrel\)], "Input"], Cell["\<\ H+ + Ar -> Ar+ + Halpha H alpha production has been measured by Andreev (1967), Hughes (19??), Hess \ (1974), and Dawson and Loyd (1974). The results differ greatly at energies \ over 1000 eV.The threshold in CM is 15.75-13.6+12.09 = 14.24 eV. A smooth \ curve through their data for energies up to 10 keV is:\ \>", "Text"], Cell[BoxData[ \(qHalphaHpAr\ := \ UnitStep[enlab - 41/40*14.24]*1.2*10^\(-6\)*\((enlab - 41/40*14.24)\)^1.2\ + \ 1. *10^\(-30\)\ //. \[IndentingNewLine]\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ enlab\ -> \ 41/40*enrel\)], "Input"], Cell["\<\ H+ + Ar -> Ar+ + HLyalpha Ly alpha production has been measured by Van Zyl et al, but I have not \ attempted to fit it as I have no need for it.\ \>", "Text"], Cell[BoxData[ \(\(hpArFitPlot\ = \ LogLogPlot[ Evaluate[{qmHpAr, qctHpAr, qiHpAr, qHalphaHpAr, qmHpArLangevin}], \[IndentingNewLine]{enrel, 0.01, 1000. }, PlotRange -> {{0.01, 1000. }, {0.01, 1000}}, PlotStyle -> plotColors, \ PlotPoints\ -> \ 10000, GridLines\ -> \ True, ImageSize\ -> 432, \ DisplayFunction\ -> \ Identity];\)\)], "Input"], Cell[BoxData[ \(\(Show[qmHpArKrsticPlot, hpArFitPlot, PlotLabel\ -> \ "\", \ ImageSize\ -> 432, \ DisplayFunction\ -> \ $DisplayFunction];\)\)], "Input"], Cell["\<\ Note that extrapolation of Krstic and Schulz (orange curve) from 100 to 1500 \ eV would seem to lead to much larger values of Qm than I got from the \ differential cross section data of Abignoli et al (1972) and shown by the red \ curve. This suggests that inelastic collisions are important at above ~ 50 \ eV.\ \>", "Subsubtitle"], Cell["H2+ Collisions with Ar.", "Subsection"], Cell["\<\ H2+ + Ar -> H2+ + Ar - elastic scattering. Apparently one does not observe elastic scattering for H2+ + Ar collisions. \ For example, there appears to be no mobility data for H2+ in Ar, presumably \ because of rapid ArH+ formation. Similarly, at energies above about 10 eV \ H2+ reacts too rapidly with Ar to form Ar+ to allow significant elastic \ scattering.\ \>", "Text"], Cell["\<\ H2+ + Ar -> ArH+ + H At energies from thermal to ~ 10 eV this reaction appears to be significantly \ larger than elastic scattering. Measurements by Smith et al (1976) and by \ Liao et al (1990) lie above and below Langevin. Smith et al (1976) claim that \ the sum of the ArH+ and Ar+ (actually ArD+ and Ar+) formation equals \ Langevin. The two measurements differ greatly on the ArH+ formation above 10 \ eV. Reactions like this that are close to Langevin at low energies are \ generally assumed to lead to isotropic scattering of the reactants.\ \>", "Text"], Cell[BoxData[ \(qmH2pAr\ := 0.85*21.6*enrel^\((\(-0.5\))\)*\ \((1 + enrel/50)\)^\((\(-1.5\))\) + 1. *10^\(-30\)\)], "Input"], Cell["\<\ H2+ + Ar -> Ar+ + H2 The threshold for ground state species from McDaniel (1964) is 15.75-15.6 = \ 0.15(?) eV, but is only 16 mV for H2+(v=2) and Ar(P1/2). Therefore these \ results are somewhat sensitive to the vibrational state of the H2+, with a \ maximum low energy cross section for H2+(v=2).\ \>", "Text"], Cell[BoxData[ \(qctH2pAr\ := 0.15*21.6*enrel^\((\(-0.5\))\)*\ \((1 + enrel/50)\)^\((\(-1.5\))\) + 10/\((1 + \((20/enrel)\))\)\ + 1. *10^\(-30\)\)], "Input"], Cell["\<\ H2+ + Ar -> H+ + Ar + H Threshold is 2.64 eV in CM = 42/40*2.64 in LAB. There is a great deal of \ uncertainty in this cross sevtion in the important energy range fro 7 to 700 \ eV. The near threshold results of Liao et al (1990) and the high energy \ results of Williams and Dunbar (1961) suggest, but do not show, a relatively \ constant cross section from 10 eV to to 2 keV, while Smith et al (1976) show \ the Q rising to 40 eV. There is also alarge difference in experimental \ results of Moran and Roberts (1968) and Liao et al (1990) near threshold.\ \>", "Text"], Cell[BoxData[ \(qDisH2pAr\ := UnitStep[enrel - 2.64]*0.6/\((1 + \((1/\((enrel - 5.4)\))\))\)*\((1 + enrel/4000)\) + 1. *10^\(-30\)\)], "Input", Evaluatable->False], Cell[BoxData[ \(qDisH2pAr\ := UnitStep[enrel - 2.64]*\(6. /\((1 + \((3/\((enrel - 2.64)\))\))\)^\((4. )\)\)/\((1 + \((enrel/ 130)\))\)*\((1 + \((enrel/1500)\)^2)\) + 1. *10^\(-30\)\)], "Input"], Cell["\<\ H2+ + Ar -> Ar+ + H2+ + e Ionization has is given by Gordeev and Panov (1964). The threshold in CM is \ 15.75 eV. A smooth curve through their data for energies up to 10 keV is:\ \>", "Text"], Cell[BoxData[ \(qiH2pAr\ := \ UnitStep[enlab - 41/40*15.75]*2.2*10^\(-4\)*\((enlab - 41/40*15.75)\)^1.1 + \ 1. *10^\(-30\)\ //. \[IndentingNewLine]\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ enlab\ -> \ 42/40*enrel\)], "Input"], Cell[BoxData[ \(\(LogLogPlot[ Evaluate[{qmH2pAr, qctH2pAr, qiH2pAr, (*\(qLyalphaH2pAr\)\(,\)*) qDisH2pAr}], \[IndentingNewLine]{enrel, 0.01, 10000}, PlotRange -> {{0.01, 10000. }, {0.01, 1000}}, PlotLabel\ -> \ "\", PlotStyle -> plotColors, PlotPoints\ -> \ 500, GridLines\ -> \ True, ImageSize\ -> 432];\)\)], "Input"], Cell["H3+ Collisions with Ar.", "Subsection"], Cell["\<\ Momentum transfer cross section is taken equal to Langevin spiraling because \ the lack of other data. The mobility of H3+ for low concentrations of H2 in \ Ar was measured by McAfee et al, Phys. Rev. 160, 130 (1967). Their limiting \ mobility at E/N < ~15 Td is assigned to the ion they find dominant, i.e., \ the H3+ ion in Ar, and is 5.7 cm^2/V at NTP or about 90% of Langevin. We \ therefore take the momentum trnasfer cross section as 1/0.9 of Langevin. We \ really should try to understand the reason for the discrepancy.\ \>", "Text"], Cell[BoxData[ \(qmH3pAr\ := 21.6/0.9\ *enrel^\((\(-0.5\))\)*\((1 + enrel/50)\)^\((\(-1.5\))\) + 1. *10^\(-30\)\)], "Input"], Cell["\<\ H3+ + Ar -> Ar+ + H2 + H Peko, Champion, and Wang (1996) and (1997) are the only results in my files \ for 15 to 400 eV LAB. The results of Gordeev and Panovl (1977) at above 3 \ keV do not extrapolate well the Peko et al. (1996). One of the Japanese \ compilations on charge transfer is Tawara, Atomic Data Nuclear Data Tables \ 22, 491 (1978) and references therein. I have only a few of the more \ relevant pages. From Peko et al (1997) this cross section dominates above 200 \ eV, but drops rapidly below 150 eV CM. The threshold in CM is 6.6 eV. A \ smooth curve is:\ \>", "Text"], Cell[BoxData[ \(qH3pArArp\ := \ UnitStep[enrel - 6.6]*20. * enrel^\((\(-0.5\))\)/\((1 + \((150/\((enrel - 6.6)\))\))\)\ + \ 1. *10^\(-30\)\)], "Input"], Cell["\<\ H3+ + Ar -> ArH+ + H2 Peko, Champion, and Wang (1996) and (1997) are the only results in my files \ for 15 to 400 eV LAB. In 1988 I tried to use the equilibrium constants and \ rate coefficients for the inverse reaction of Villinger et al (1982) to \ derive this cross section. I got values about 25% of Langevin for 0.7 to 2 \ eV. From Peko et al (1997) this cross section is a small fraction of the \ total until the energy is below about 10 eV CM, i.e., the results are \ consistent with Villinger et al. The threshold in CM is 0.41 eV from Peko et \ al.. We draw a smooth curve that drops rapidly above 10 eV as is typical of \ ion transfer: This curve is essentially the same as that I published in \ 1992.\ \>", "Text"], Cell[BoxData[ \(qH3pArArHp\ := \ UnitStep[enrel - 0.41]*5. *\(enrel^\((\(-0.5\))\)/\((1 + \((0.42/\((enrel - 0.41)\))\)^4)\)\)/\((1 + \((enrel/ 10)\)^3)\)\ \ + \ 1. *10^\(-30\)\)], "Input"], Cell["\<\ H3+ + Ar -> Ar + H+ + H2 Peko, Champion, and Wang (1996) are the only results in my files for 15 to \ 400 eV LAB. From Peko et al (1997) this cross section dominates from 15 to \ 150 eV CM. Similar results had been obtained by Prokof'ev at al (1978) for 1 \ to 40 eV. The results of Williams and Dunbar at above 3 keV do not \ extrapolate well the Peko et al.. The threshold in CM is 4.4 eV. A smooth \ curve through Peko et al and extended to 10 keV is:\ \>", "Text"], Cell[BoxData[ \(qDisH3pArHp\ := \ UnitStep[enrel - 4.4]*50. * enrel^\((\(-0.5\))\)/\((1 + \((3. /\((enrel - 4.4)\))\))\)*\((1 + \((enrel/800)\) 0.7)\)\ + \ 1. *10^\(-30\)\)], "Input"], Cell["\<\ H3+ + Ar -> Ar + H2+ + H Peko, Champion, and Wang (1996) are the only results in my files for 15 to \ 400 eV LAB. The results of Williams and Dunbar at above 3 keV do not \ extrapolate well the Peko et al.. The threshold in CM is 6.2 eV. A smooth \ curve through Peko et al and extended to 10 keV is:\ \>", "Text"], Cell[BoxData[ \(qDisH3pArH2p\ := \ UnitStep[enrel - 6.2]*0.8/\((1 + \((6.21/\((enrel - 6.2)\))\)^8)\)\ + \ 1. *10^\(-30\)\)], "Input"], Cell["\<\ H3+ + Ar -> Ar+ + H3+ + e Ionization has is given by Gordeev and Panov (1964) for energies above 1 keV. \ The threshold in CM is 15.75 eV. A smooth curve through their data for \ energies up to 10 keV is:\ \>", "Text"], Cell[BoxData[ \(qiH3pAr\ := \ UnitStep[enlab - 43/40*15.75]*1.8*10^\(-2\)*\((enlab - 43/40*15.75)\)^0.6 + \ 1. *10^\(-30\)\ //. \[IndentingNewLine]\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ enlab\ -> \ 43/40*enrel\)], "Input"], Cell[BoxData[ \(\(LogLogPlot[ Evaluate[{qmH3pAr, qH3pArArp, qDisH3pArHp, qH3pArArHp, qDisH3pArH2p, qiH3pAr}], \[IndentingNewLine]{enrel, 0.01, 10000}, PlotRange -> {{0.01, 10000. }, {0.01, 1000}}, PlotLabel\ -> \ "\", PlotStyle -> plotColors, PlotPoints\ -> \ 5000, GridLines\ -> \ True, ImageSize\ -> 432];\)\)], "Input"], Cell["ArH+ Collisions with Ar.", "Subsection"], Cell["\<\ ArH+ + Ar -> ArH+ + Ar Momentum transfer cross section is taken equal to Langevin spiraling because \ the lack of other data. The mobility of ArH+ for low concentrations of H2 in \ Ar was measured by McAfee et al, Phys. Rev. 160, 130 (1967). As E/N \ increases and the H2 fraction decreases the mobility drops to values said to \ approach 1.7 cm^2/V or about 70% of Langevin.and is attributed to ArH+. We \ therefore take the momentum transfer cross section as 1/0.7 of Langevin. \ Does the cross section approached Langevin at lower energies?\ \>", "Text"], Cell[BoxData[ \(qmArHpAr\ := 21.6/0.7\ \ *enrel^\((\(-0.5\))\)*\((1 + enrel/50)\)^\((\(-1.5\))\) + 1. *10^\(-30\)\)], "Input"], Cell["\<\ ArH+ + Ar -> H+ + 2Ar The energy required is 6.55 - 0.41 - 15.76 + 13.6 = 3.98 from Peko et al \ (1996). I do not know where the following cross section came from, so it \ is just an uneducated guess and only serves as a marker in models..\ \>", "Text"], Cell[BoxData[ \(qDisArHpHp\ := UnitStep[enrel - 3.98]*\(1.4/\((\((40/\((enrel - 3.98)\))\)^2.5 + 1)\)\)/\((\((enrel/30)\)^2 + 1)\)^0.22 + \ 1. *10^\(-30\)\)], "Input"], Cell["\<\ ArH+ + Ar -> Ar+ + H + Ar The energy required is 6.55 - 0.41 = 6.14 from Peko et al (1996). I do not \ know where the following cross section came from, so it is just an uneducated \ guess and only servers as a marker in models.\ \>", "Text"], Cell[BoxData[ \(qDisArHpArp\ := UnitStep[enrel - 6.14]*\(1.4/\((\((40/\((enrel - 6.14)\))\)^2.5 + 1)\)\)/\((\((enrel/30)\)^2 + 1)\)^0.22 + \ 1. *10^\(-30\)\)], "Input"], Cell[BoxData[ \(\(LogLogPlot[ Evaluate[{qmArHpAr, qDisArHpHp, qDisArHpArp}], \[IndentingNewLine]{enrel, 0.01, 10000}, PlotRange -> {{0.01, 10000. }, {0.01, 1000}}, PlotLabel\ -> \ "\", PlotStyle -> plotColors, PlotPoints\ -> \ 5000, GridLines\ -> \ True, ImageSize\ -> 432];\)\)], "Input"], Cell["H- Collisions with Ar.", "Subsection"], Cell["\<\ Because of the low cross sections for e + H2 -> H- + H, the H- density in \ most H2-Ar discharges is expected to be very low.\ \>", "Subsubtitle"], Cell["\<\ H- + Ar -> H- + Ar The momentum transfer cross section is taken equal to Langevin spiraling \ because the lack of other data. According to Viehland and Mason (1995) the \ mobility of H- in Ar has not been measured. One could calculate the low E/N \ limit using the Langevin formula and extrapolate it to higher E/N.\ \>", "Text"], Cell[BoxData[ \(qmHnAr\ := 21.6\ *enrel^\((\(-0.5\))\)*\ \((1 + enrel/50)\)^\((\(-1.5\))\) + 1. *10^\(-30\)\)], "Input"], Cell["\<\ H- + Ar -> H + e + Ar Detachment cross section measurements are given by, for example, Champion et \ al (1976) for 5 to 100 eV LAB and Risley and Geballe (1974). A fit to their \ data as compiled in Phelps (1992) is\ \>", "Text"], Cell[BoxData[ \(qDetHnAre\ := UnitStep[enlab - 0.754]*2.45*\(\((enlab - 0.754)\)^0.2/\((1 + \((0.78/\((enlab - 0.754)\))\)^4)\)\)/\((1 + enlab/300)\)*\((1 + \((enlab/500)\)^1.2)\) + 1. *10^\(-30\)\ \ //. \ enlab\ -> \ 41/40*enrel\)], "Input"], Cell["\<\ H- + Ar -> H+ + 2 e + Ar Ionization-detachment cross section measurements are given by Williams \ (1967). A fit to their data as compiled in Phelps (1992) is\ \>", "Text"], Cell[BoxData[ \(qiHnAr\ := \ UnitStep[enlab - 16.6]*0.21*\((\((enlab - 16.6)\)/2000)\)^0.75 + 1. *10^\(-30\)\ \ //. \ enlab\ -> \ 41/40*enrel\)], "Input"], Cell[BoxData[ \(\(LogLogPlot[ Evaluate[{qmHnAr, qDetHnAre, qiHnAr}], \[IndentingNewLine]{enrel, 0.01, 10000}, PlotRange -> {{0.01, 10000. }, {0.01, 1000}}, PlotLabel\ -> \ "\", PlotStyle -> plotColors, PlotPoints\ -> \ 5000, GridLines\ -> \ True, ImageSize\ -> 432];\)\)], "Input"], Cell["\<\ Beware! Nothing checked beyond here. The following are from a 1991 draft \ paper and model program, but I have not found much else.\ \>", "Subtitle", FontColor->RGBColor[1, 0, 0]], Cell["H Collisions with Ar.", "Subsection"], Cell[BoxData[ \(qmHAr\ := 5.4\ *enrel^\((\(-0.5\))\)\ \((1 + enrel/56)\)^\((\(-1.5\))\) + 1. *10^\(-30\)\)], "Input"], Cell[BoxData[ \(qeArp\ := UnitStep[enrel - 40]*1.8*10^\((\(-6\))\)\ *\((enrel - 40)\)^\((1.8)\)/\((1 + enrel/3300)\)^\((1.5)\) + 1. *10^\(-30\)\ // Re\)], "Input"], Cell[BoxData[ \(qeArp2\ := UnitStep[enrel - 15]*\((\((2\ *\ 10^\((\(-7\))\)\ *\((enrel - 15)\)^\ \((3.5)\))\)/\((\((1 + enrel/120)\)^4)\) + \((1.7*\ 10^\((\(-7\))\)\ enrel^2)\)/\((1 + \((enrel/ 1000)\))\)^5 + \((1.3\ *\ 10^\((\(-8\))\)\ \((enrel - 15)\)^3)\)/\((1 + \((enrel/ 1000)\))\)^\ 5)\) + 1. *10^\(-30\)\ // \ Re\)], "Input"], Cell[BoxData[ \(qHnegArp\ := UnitStep[enrel - 23]*\ 0.045*\((1 - Exp[\(-enrel\)/200])\)*\((1 + Exp[\(-enrel\)/100]* Sin[\((1500/enrel)\)^\ \((0.5)\)])\)/\((1 + \((enrel/ 500)\))\) + \n UnitStep[ enrel - 450]\ *6.5\ *10\ ^\((\(-11\))\)*\ \((enrel - 450)\)^3/\((1 + \((enrel/2500)\))\)^4 + 1. *10^\(-30\)\ \ // Re\)], "Input"], Cell[BoxData[ \(qHArHalpha\ := UnitStep[enrel - 12]*\ \(\((1.4)\)/\((1 + \((\ 40/\((enrel - 12)\))\)^\((2.5)\))\)\)/\((1 + \((enrel/ 30)\)^\ 2)\)^\((0.22)\) + 1. *10^\(-30\)\ // Re\)], "Input"], Cell[BoxData[ \(qHArLyalpha\ := UnitStep[enrel - 10.2]*\((\(2/\((1 + \((\ 40/\((enrel - 10.2)\)\ )\)^3)\)\)/\((1 + \((enrel/ 40)\)^\ 2.5)\)^\((0.22)\) + 1.5\ *\((enrel/1000)\)^\ 2/\((1 + \((enrel/1000)\)^\ \((2.6)\))\))\) + 1. *10^\(-30\)\)], "Input"], Cell[BoxData[ \(\(LogLogPlot[ Evaluate[{qmHAr, qeArp, qeArp2, qHnegArp, qHArHalpha, qHArLyalpha}], \[IndentingNewLine]{enrel, 0.01, 10000}, PlotRange -> {{0.01, 10000. }, {0.01, 1000}}, PlotLabel\ -> \ "\", PlotStyle -> plotColors, PlotPoints\ -> \ 5000, GridLines\ -> \ True, ImageSize\ -> 432];\)\)], "Input"], Cell[BoxData[ \(Quit[]\)], "Input"], Cell["H2 Collisions with Ar.", "Subsection"], Cell[BoxData[ \(qmH2Ar\ := 11.7\ *enrel^\((\(-0.3\))\)*\ \((1 + enrel/47.4)\)^\((\(-1.7\))\) + 1. *10^\(-30\)\)], "Input"], Cell[BoxData[ \(qmH2Ar\ /. \ enrel\ -> \ 1000\)], "Input"], Cell["Ar+ Collisions with H2. enrel<0.5 eV", "Subsection"], Cell[" Ar++H2\[Rule]H2+ + Ar", "Text"], Cell[BoxData[ \(A4H2N = 2 E - 19\)], "Input"], Cell["Ar++H2\[Rule]ArH+ +H", "Text"], Cell[BoxData[ \(A4H5N = 5 E - \(19/\((W4^ .5)\)\)/\((\((W4/100)\) ** 3 + 1)\)\)], "Input"], Cell[BoxData[ \(qArpH2\ := 42\ *enrel^\((\(-0.36\))\) + 1. *10^\(-30\)\)], "Input"], Cell[BoxData[ \(qArpH2\ /. \ enrel\ -> \ 1000\)], "Input"], Cell["ArH+ Collisions with H2.", "Subsection"], Cell["\<\ ArH+ + H2 -> ArH+ + H2 Apparently elastic scattering dominates, although I would have expected the \ following reaction cross section to be closer to Langevin.\ \>", "Text"], Cell[BoxData[ \(qmArHpH2H3p = 70/\((enlab)\)^0.5\ \ //. \ enlab\ -> \ 43/2*enrel\)], "Input"], Cell["\<\ ArH+ + H2 -> H3+ + Ar Because this reaction is exothermic by 0.41 eV, I would expect the cross \ section to be closer to the Langevin capture cross section..\ \>", "Text"], Cell[BoxData[ \(qArHpH2H3p = 33. /\((enlab)\)^1.33\ \ //. \ enlab\ -> \ 43/2*enrel\)], "Input"], Cell["Ar* Collisions with H2", "Subsection"], Cell["Excitation Transfer", "Text"], Cell[BoxData[ \(TeXSave["\", "\"]\)], "Input", Evaluatable->False] }, FrontEndVersion->"4.1 for Microsoft Windows", ScreenRectangle->{{0, 1024}, {0, 695}}, CellGrouping->Manual, WindowSize->{830, 638}, WindowMargins->{{0, Automatic}, {Automatic, 0}}, StyleDefinitions -> "AvpStyle.nb" ] (******************************************************************* Cached data follows. 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