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HII Regions Library

Introduction

Star formation in galaxies is traced by the presence of emission lines, produced by the ionized gas surrounding young star clusters. In particular, hydrogen (H) recombination lines intensity is a direct measure of the number of massive stars still alive. Thus, emission lines are important tracers of the current star formation rate (SFR). These regions are often embedded into dusty environments, and the effects of dust may be significant. Therefore, it is fundamental to model the nebular emission within a context that takes into account star-light reprocessing by dust. For this reason, during my PhD, I implemented the modelling of nebular emission by HII regions into GRASIL that was originally developed to simulate the spectral energy distribution (SED) of dusty galaxies. The implementation is based on a pre-computed library of HII region emission models.

You can find more details on this work in Panuzzo et al. 2003 and in my PhD Thesis.

Organization of the library

The library of HII region emission models provides the emission line luminosities for a given ionizing stellar population. It can be used in other spectrophotometric codes. You can freely download the library and use it in your code. Please acknowledge if you use this library for a publication, citing Panuzzo et al. 2003.

The library provides the emission line luminosities as a function of:

It is composed by plain ASCII files, one for each value of hydrogen density (in number of ions per cm3) and filling factor. In the following table you can find the library’s files.

densityfilling factornamedensityfilling factorname
101.0hii_d10f10.dat.gz301.0hii_d30f10.dat.gz
100.1hii_d10f01.dat.gz300.1hii_d30f01.dat.gz
100.01hii_d10f001.dat.gz300.01hii_d30f001.dat.gz
1001.0hii_d100f10.dat.gz3001.0hii_d300f10.dat.gz
1000.1hii_d100f01.dat.gz3000.1hii_d300f01.dat.gz
1000.01hii_d100f001.dat.gz3000.01hii_d300f001.dat.gz
10001.0hii_d1000f10.dat.gz30000.1hii_d3000f01.dat.gz
10000.1hii_d1000f01.dat.gz30000.01hii_d3000f001.dat.gz
10000.01hii_d1000f001.dat.gz30000.001hii_d3000f0001.dat.gz
100000.1hii_d10000f01.dat.gz
100000.01hii_d10000f001.dat.gz
100000.001hii_d10000f0001.dat.gz

Parameter space

The HII region models are computed for different values of metallicity, namely: Zgas=0.0008, 0.004, 0.008, 0.015, 0.02, 0.03, 0.04, 0.05, where 0.02 means solar metallicity.

The space of Q parameters is divided into two grids, identified by a grid index. In the first grid, with index number equal 1, QHe/QH is > 0.05; in the second (grid index = 2) QHe/QH is < 0.05.

In grid number 1, QHe/QH=0.05+0.05625*i with i=0,...,8; QO/QHe=0.13+0.1*j with j=0,...,5.

In grid 2, QHe/QH=0.05, 0.025, 0.01, 0.005, 0.0025, 0.0001, 0.; while QO/QHe=0.+0.1*j with j=0,...,4.

In both the grids, QH=1046+0.2*k with k=0,...,30.

Format

The first line is an header; each following line correspond to an HII region model. This is an example of the first two lines of a library file (namely hii_d10f01.dat):

#density=  10.00 filling=  0.100 1)name  2)numgrid  3)zeta  4)lum  5)shi  6)sx  7)shei  8)so  9-135)intfluxline
bZ01H01E01O01 1 .0008 38.622  -2.0000  -2.4590  -3.3010  -4.1871 664505961859289591245900558898587045865964200631....

Description byte by byte

CharactersFormatDescription
1-13A13Name of the model: bytes 1-13 are a string that identify the name of the input file for CLOUDY.
15I1Grid index
17-21F5.4Metallicity
23-28F6.3Log of the luminosity of analytical spectrum in erg/s
30-37F8.4Log(QH/1050 photons/second)
39-46F8.4Log(QX/1050): QX is the number of photons per second with a wavelength shorter than 750 Å
48-55F8.4Log(QHe/1050)
57-64F8.4Log(QO/1050)
66-636114I5Line luminosity

Bytes from 66 to 636 correspond to the flux of 114 emission lines, an integer of 5 digits for each emission line. The line luminosity can be obtained as Luminosity=exp(intLine/1000.-50.) where intLine is the integer read from the library. I wrote a FORTRAN90 module that provide a subroutine to read these libraries.

Computed lines

In the following table there is the list of the computed lines. The order is the same that you can find in the library files.

  1. Ly α 1216Å

  2. Ly β 1025Å

  3. Ly γ 972Å

  4. Ly δ 949Å

  5. Ly ε 937Å

  6. Ly ζ 930Å

  7. Ly η 926Å

  8. Ly θ 922Å

  9. H α 6563Å

  10. H β 4861Å

  11. H γ 4340Å

  12. H δ 4102Å

  13. H ε 3970Å

  14. H ζ 3889Å

  15. H η 3835Å

  16. H θ 3798Å

  17. Pa α 18752Å

  18. Pa β 12819Å

  19. Pa γ 10939Å

  20. Pa δ 10050Å

  21. Pa ε 9546Å

  22. Pa ζ 9229Å

  23. Pa η 9015Å

  24. Pa θ 8863Å

  25. Br α 40515Å

  26. Br β 26254Å

  27. Br γ 21657Å

  28. Br δ 19447Å

  29. Br ε 18175Å

  30. Br ζ 17363Å

  31. Br η 16808Å

  32. Br θ 16408Å

  33. Pf α 74585Å

  34. Pf β 46529Å

  35. Pf γ 37398Å

  36. Pf δ 32964Å

  37. Pf ε 30386Å

  38. Pf ζ 28724Å

  39. Pf η 27577Å

  40. Pf θ 26746Å

  41. Hu α 12.4µm

  42. Hu β 75011Å

  43. Hu γ 59071Å

  44. Hu δ 51277Å

  45. Hu ε 46716Å

  46. Hu ζ 43756Å

  47. Hu η 41700Å

  48. Hu θ 40201Å

  49. HeI 4472Å

  50. HeI 5877Å

  51. HeI 6680Å

  52. HeI 10833Å

  53. HeI 3889Å

  54. HeI 7065Å

  55. [CI]9850Å

  56. [CI]8727Å

  57. [CI]4621Å

  58. [CI]610µm

  59. [CI]369µm

  60. [CII]157.7µm

  61. CII]2326Å

  62. [NI]5200Å

  63. [NI]3467Å

  64. [NI]10405Å

  65. [NII]6585Å

  66. [NII]6549Å

  67. [NII]5756Å

  68. [NII]122µm

  69. [NII]205µm

  70. NII]2141Å

  71. [NIII]57µm

  72. [OI]6302Å

  73. [OI]6365Å

  74. [OI]5578Å

  75. [OI]63µm

  76. [OI]145µm

  77. [OII]3727Å

  78. [OII]7327Å

  79. [OII]2471Å

  80. OIII]1663Å

  81. [OIII]5007Å

  82. [OIII]4960Å

  83. [OIII]4364Å

  84. [OIII]2321Å

  85. [OIII]88µm

  86. [OIII]52µm

  87. [NeII]12.8µm

  88. [NeIII]15.5µm

  89. [NeIII]36µm

  90. [NeIII]3870Å

  91. [NeIII]3968Å

  92. [NeIII]3343Å

  93. [NeIII]1815Å

  94. MgII 2800Å

  95. [SiII]35µm

  96. [SII]10331Å

  97. [SII]6732Å

  98. [SII]6717Å

  99. [SII]4070Å

  100. [SII]4078Å

  101. [SIII]18.7µm

  102. [SIII]33.5µm

  103. [SIII]9533Å

  104. [SIII]9071Å

  105. [SIII]6314Å

  106. [SIII]3723Å

  107. [SIV]10.5µm

  108. [ArII]7µm

  109. [ArIII]7138Å

  110. [ArIII]7753Å

  111. [ArIII]5193Å

  112. [ArIII]3110Å

  113. [ArIII]22µm

  114. [ArIII]9µm

Problems?!?

Send me an email at pasquale.panuzzo@observatoiredeparis.psl.eu!

References
  1. Panuzzo, P., Bressan, A., Granato, G. L., Silva, L., & Danese, L. (2003). Dust and nebular emission: I. Models for normal galaxies. Astronomy & Astrophysics, 409(1), 99–114. 10.1051/0004-6361:20031094
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