J/A+AS/136/395 IRON Project XXXVII. Fe VI collision strengths (Chen+ 1999) ================================================================================ Atomic data from the Iron Project. XXXVII. Electron impact excitation collision strengths and rate coefficients for Fe VI Chen G.X., Pradhan A.K. =1999A&AS..136..395C (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Atomic physics Keywords: electron collision rates - fine structure transitions - hot stellar sources: white dwarfs - H II regions: planetary nebulae Abstract: Collision strengths and Maxwellian-averaged rate coefficients have been calculated for 3,160 non-vanishing transitions among 80 fine structure levels, dominated by configurations 3d^3^, 3d^2^4s, and 3d^2^4p in Fe VI. Collision strengths are calculated using the R-matrix method with a 34-term close-coupling target expansion and for electron energies up to 10 Rydbergs. Detailed comparisons of rate coefficients are presented with the relativistic Breit-Pauli calculations using a 19-level expansion corresponding to the first 8 LS terms dominated by the ground configuration 3d^3^. For the low-lying transitions of practical interest there is excellent agreement, better than 10%, among three sets of rate coefficients calculated using 34 term and 8-term non-relativistic calculations and the 19-level Breit-Pauli calculation, indicating that (i) the relativistic effects are not too significant, and (ii) the numerical uncertainties associated with the resolution of the extensive resonances in the collision strengths are small. Rate coefficients are tabulated in a range of temperatures, 10^4^-10^6^K, where Fe VI is normally abundant in radiatively photoionized or collisionally ionized plasmas sources. The present rates for Fe VI are expected to find applications in UV spectral diagnostics of hot stellar sources and planetary nebulae. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file level4 35 80 Levels for table4 table4 80 8798 Maxwellian-averaged collision strengths Upsilon(i,j) for the 3160 transitions between the 140 levels at T=10000-1000000K in Fe VI prog.f 74 36 Fortran code to read the data file table4 -------------------------------------------------------------------------------- Structure of file table4: -------------------------------------------------------------------------------- Records Format Explanations -------------------------------------------------------------------------------- 1- 4 20A4 Title 5 3I5 Nuclear charge number Z (26), number of electrons per ion N (21) and the number of levels (80) 6- 85 2I4,1X,F8.6,(A8) Level index, twice total angular momentum 2J, and the energy (configuration and term) 86 2I8 Number of transitions NTR (3160=80*79/2) and number of temperatures NTEMP (21) 87- 481 7x,8(3x,i2,i3,1x) Transition keys ((i,j),i=1,j-1),j=2,ntr)), with i and j being the initial and the final levels. 482 F8.0 Temperature T = 2000 K 483- 877 8(1PE9.2) Upsilons for the corresponding transitions specified in Record 87 - 481. 878-8797 F8/8((1PE9.2,1X) Repeating the above for 20 more temperatures: 10000, 20000, 30000, 40000, 50000, 60000, 70000, 80000, 90000, 100000, 150000, 200000, 250000, 300000, 400000, 500000, 600000, 700000, 800000, 900000, 1000000 -------------------------------------------------------------------------------- See also: J/A+AS/103/273 : IRON Project II IR collision strengths of C-like ions J/A+A/283/319 : IRON Project III B-like ions J/A+AS/108/1 : IRON Project V Collision strengths of O-like ions J/A+A/293/953 : IRON Project VI Fe II collision strengths J/A+A/293/967 : IRON Project VII Fe II radiative transitions J/A+AS/109/193 : IRON Project VIII Electron excitation of Ti-like ions J/A+AS/119/509 : IRON Project XVII Radiative transition in Fe III J/A+AS/119/523 : IRON Project XVIII Electron impact for Fe III J/A+AS/120/361 : IRON Project XIX Fe II radiative transitions J/A+AS/123/159 : IRON Project XXII C and O radiative rates J/A+AS/123/575 : IRON Project XXIII Fe XXII excitation rate coefficients J/A+AS/131/499 : IRON Project XXIX Boron isoelectronic sequence J/A+AS/131/153 : IRON Project XXXI Fe XII electron excitation J/A+AS/126/373 : IRON Project XXVII Fe IV collision strengths J/A+AS/135/347 : IRON Project XXXV Fe XXIV & Fe XXV oscillator strengths J/A+AS/137/165 : IRON Project XXXVIII Fe XV electron excitation J/A+AS/143/483 : IRON Project XLII Fe XXI electron impact excitation J/A+AS/144/141 : IRON Project XLIII Fe V transition probabilities J/A+AS/147/111 : IRON Project XLIV Fe VI trans. prob. & line ratio J/A+AS/147/253 : IRON Project XLV Ar XIII, Fe XXI trans. probabilities J/A+A/365/268 : IRON Project XLVII Ni III electron impact excitation J/A+A/372/1078 : IRON Project XLIX Fe XX electron impact excitation J/A+A/372/1083 : IRON Project L Fe XIX electron impact excitation J/A+A/394/753 : IRON Project LI Fe IX electron impact excitation J/A+A/408/789 : IRON Project LIII Fe XVII transition probabilities J/A+A/413/779 : IRON Project LIV Fe XX transition probabilities J/A+A/420/763 : IRON Project LV Ni II electron impact excitation J/A+A/437/345 : IRON Project LIX Fe IV transition probabiliti J/A+A/448/779 : IRON Project LXI Fe IV radiative transitions J/A+A/457/721 : IRON Project LXII Fe XVIII allowed and forbidden trans. J/A+A/466/763 : IRON Project LXIII Fe^19+^ electron impact excitation Byte-by-byte Description of file: level4 -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 2 I2 --- Index Level index 5- 6 I2 --- 2J Twice total angular momentum 10- 17 F8.6 Ry E Experimental energy 23- 35 A13 --- Term configuration and electronic term -------------------------------------------------------------------------------- History: * 02-Apr-1999: first version * 17-Jun-1999: table4 was updated (new version supplied by the author) * 18-Jul-1999: table4 newly updated (a newer version supplied by the author) Acknowledgements: Guo-xin Chen References: 1993A&A...279..298H : IRON Project I Goal and methods 1994A&AS..107...29S : IRON Project IV Electron excitation of F-like ions 1995A&AS..110..209P : IRON Project IX Electron excitation of Cl-like ion 1995A&AS..111..347G : IRON Project X Si- & S-like ions IR coll. strengths 1996A&AS..115..151S : IRON Project XI Ar VI, K VII & CaVIII fine-structure 1995A&AS..114..367B : IRON Project XII V-like ions electron excitation 1996A&AS..115..551B : IRON Project XIII Ni II & Fe II electron excitation 1996A&A...309..677S : IRON Project XIV Fe XIV fine-structure transition 1996A&AS..118..157K : IRON Project XV He II & Fe XXVI Electron excitation 1996A&AS..119..105B : IRON Project XVI Fe V oscillator strengths 1997A&AS..122..167B : IRON Project XX Fe I oscillator strengths 1997A&AS..122..177P : IRON Project XXI Fe I fine-structure transition 1997A&AS..126..105B : IRON Project XXIV Fe XXIV electron excitation 1998A&AS..127..545B : IRON Project XXV Fe XII electron excitation 1997A&AS..126..365B : IRON Project XXVI Fe IV oscillator strengths 1998A&AS..129..161B : IRON Project XXVIII F-like ions fine-structure trans. 1999A&AS..134..369S : IRON Project XXX P III, S IV & Cl V collision data 1998A&AS..133..245G : IRON Project XXXII Ar III effective collision strength 1999A&AS..135..159M : IRON Project XXXIII Carbon radiative rates 1999A&AS..136..385E : IRON Project XXXIV Fe XVI electron impact excitation 1999A&AS..137..175C : IRON Project XXXVI Fe XXIII electron excitation 1999A&AS..137..529B : IRON Project XXXIX Ni II oscillator strengths 2000A&AS..141..285S : IRON Project XL Fe XIV electron excitation 2000A&AS..142..313B : IRON Project XLI Fe VII electron excitation 2001A&A...365..258P : IRON Project XLVI Fe X electron excitation 2003A&A...401.1177C : IRON Project LII Ni^24^ electron excitation 2005A&A...436.1123M : IRON Project LVII Ni IV radiative transition rates 2005A&A...433..717S : IRON Project LVIII Fe XII electron impact excitation 2006A&A...446..361W : IRON Project LX Fe^17+^ electron impact excitation ================================================================================ (End) Patricia Bauer [CDS] 17-Jun-1999