everall_1987
============

N\. J\. Everall, J\. P\. Partanen, J\. R\. M\. Barr and M\. J\. Shaw, "Threshold measurements of stimulated Raman scattering in gases using picosecond KrF laser pulses", Opt\. Commun\. 64, 393 \(1987\)

`Source record <https://github.com/LupoLab/optmat/blob/main/src/optmat/data/sources/everall_1987.toml>`__ · :doc:`Catalogue </the-data/sources>` · :doc:`Review register </register>`

DOI: `10\.1016/0030\-4018\(87\)90258\-6 <https://doi.org/10.1016/0030-4018%2887%2990258-6>`__

**Source kind:** measurement

**Recorded technique:** Stimulated Raman scattering thresholds with 20 ps KrF laser pulses at 248 nm \(a synchronously pumped dye oscillator at 746 nm, fibre\-transported, dye\-amplified, frequency\-tripled and amplified in a KrF amplifier to up to 200 uJ\), focused by a 2\.5 m lens into a 3 m Raman cell at up to 5 atm; threshold taken as about 10 % pump\-to\-Stokes conversion, pulse energies to \+\-25 % \(pp\. 394\-395\)\. Thresholds compared with the transient plane\-wave estimate, Eqs\. \(2\) and \(7\), using literature cross sections and linewidths \(pp\. 393\-394\)\.

**Materials in structured entries:** CH4, H2, N2, O2, SF6

**Dataset quantities:** dephasing\_time, raman\_cross\_section, raman\_linewidth

**Contents:** 15 datasets; 0 formulas.

Curation notes
--------------

Journal pages 393\-397 = PDF pages 1\-5 \(page n of the PDF is p\. 392 \+ n\)\. Identity checked on the first page\.

THE TABLE \(p\. 396; the library's unlabelled tbl\_4397977c2c69, caption 'Comparison of calculated \(eq\. \(7\)\) and measured thresholds at 5 atm\. An asterisk indicates that threshold was not reached with the available pump energy'\)\. Per gas\: dsigma/dOmega \(10^\-29 cm^2 sr^\-1\), Delta nu\_R \(cm^\-1\), T2 \(ps\), threshold calculated and measured \(uJ\)\. Table note\: 'Cross sections for CH4, H2, N2 and O2\: ref\. \[15\] \(Bischel and Black\)\. Cross sections for SF6 and NH3 were extrapolated from data in ref\. \[16\] \(Schrotter and Klockner\) assuming nu^4 scaling\. Linewidth data\: CH4 \[17\] \(Taira et al\.\), H2 \[9\] \(Owyoung\), SF6 \[18\] \(Esherick and Owyoung\), NH3 \[19\], N2, O2 \[1\] \(Murray et al\.\)'\. So\: \- dsigma/dOmega and Delta nu\_R are taken from others \(use = "reproduced"\); nothing in the table but the measured thresholds is this paper's measurement; \- T2 is calculated from Delta nu\_R\: 'The dephasing time T2 of a Raman scattering medium is defined as the inverse of the scattering bandwidth \(T2 = 1/pi Delta nu\_R, fwhm\)' \(p\. 393\) \(use = "check"\); 1/\(pi c Delta nu\_R\) reproduces the printed T2 for CH4 \(27\.94\), SF6 \(6\.64\), O2 \(5\.90\) and N2 \(7\.08\), and for H2 the printed 1008 ps implies 0\.0105 cm^\-1 where the table rounds to 0\.01; \- the linewidths are FWHM at 5 atm \(the table's pressure; not restated per value; temperature not stated\)\. For H2 \(0\.01 cm^\-1 = 300 MHz at 5 atm\) the Dicke\-narrowed regime applies; the paper gives no law\. CH4's 0\.38 cm\-1 equals Taira et al\.'s 0\.32 \+ 0\.012 p cm\-1 \(hanna\_1986\) at 5 atm\. The transitions are not named \(the vibrational Q branches used for SRS\: CH4 nu1, SF6 nu1, H2 Q\(1\) presumably, O2 and N2 v = 0\-1\)\.

THRESHOLDS \(no quantity; for the record\)\: calculated / measured \(uJ\) at 5 atm\: CH4 15 / 30 \+\- 15; NH3 55 / 95 \+\- 20; H2 60 / 155 \+\- 20; SF6 65 / 120 \+\- 30; O2 100 / not reached; N2 225 / not reached \(asterisks\)\. 'The measured thresholds \.\.\. seem to be systematically higher by about a factor of 2 than the values based on the presented theory' \(p\. 395\)\. Fig\. 2\: the CH4 threshold against pressure, 2\-5 atm \(a figure only\)\. N2 at 5 atm showed 'a large spectral broadening \(of the order of 10 nm\)' of the pump without Raman generation \(pp\. 396\-397\)\.

THEORY \(p\. 393\-394; notes only\)\: Eq\. \(2\), gamma = \(2 lambda\_s^3 N/\(h c pi Delta nu\_R\)\) \(dsigma/dOmega\); the threshold condition Eq\. \(5\), gamma I\_pm l = 25 \+ 131\.5 T2/t\_p \(Gaussian pulse, t\_p FWHM; 'error \< 15%' against the analytical solution\), and Eq\. \(7\), E\_T = \(4\.2 t\_p \+ 22\.3 T2\) lambda\_p/gamma, the focused\-beam threshold energy\. Not recorded as formulas\: threshold models, not material properties\.

NH3 is not a curated species \(dsigma 9\.2e\-29 cm^2/sr, Delta nu\_R ~4\.0 cm^\-1, T2 2\.7 ps, not extracted\)\.

FOR SOLPROP\: the SF6 vibrational linewidth constant 4\.8229e10 Hz is 1/\(pi x 6\.6 ps\), this table's T2 at 5 atm \(itself 1/\(pi c x 1\.6 cm^\-1\) from Esherick and Owyoung's linewidth\)\: a calculated value at one pressure, taken by solprop as density\-independent\. solprop's N2 '6 ps' \(5\.3052e10 Hz = 1/\(pi x 6 ps\)\) is not this paper's N2 value \(7\.1 ps at 5 atm, from Murray et al\.'s approximate 1\.5 cm^\-1\)\.

**Recorded bibliographic identity status:** VALIDATED\_WITH\_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets
--------

everall\_1987/dsigma\_CH4
~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "dsigma_CH4",
     "material": "CH4",
     "file": "CH4/everall_1987__dsigma_CH4.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_cross_section",
     "unit": "cm2/sr",
     "scale": 1e-29,
     "abscissa_unit": "nm",
     "use": "reproduced",
     "reproduced_from": [
       "bischel_1983"
     ],
     "parameters": {
       "transition": "nu1 Q branch (the band is not named in the paper)"
     }
   }

Table \(p\. 396\), dsigma/dOmega at the 248 nm KrF pump, used in Eq\. \(2\); the table note\: 'Cross sections for CH4, H2, N2 and O2\: ref\. \[15\]'\. Polarization and definition not stated\. Ref\. \[15\] is bischel\_1983 \(re\-pointed 2026\-09\-27\), which prints no value at 248 nm\: its single\-resonance fit \(Table 1\) gives 15\.7e\-29 \(248\.0 nm\) and 15\.5e\-29 \(248\.4 nm\), 2\-3 % above this 15\.3\.

everall\_1987/linewidth\_CH4
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "linewidth_CH4",
     "material": "CH4",
     "file": "CH4/everall_1987__linewidth_CH4.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_linewidth",
     "unit": "cm-1",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "reproduced",
     "reproduced_from": [
       "Y. Taira, K. Ide and H. Takuma, Chem. Phys. Lett. 91 (1982) 299"
     ],
     "parameters": {
       "transition": "nu1 Q branch (the band is not named in the paper)",
       "width": "fwhm",
       "perturber": "self"
     }
   }

Table \(p\. 396\), the Raman linewidth Delta nu\_R at 5 atm \(the caption\: thresholds 'at 5 atm'\), FWHM\: 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\. Taken from the table note's linewidth reference; temperature not stated \(room\)\.

everall\_1987/T2\_CH4
~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "T2_CH4",
     "material": "CH4",
     "file": "CH4/everall_1987__T2_CH4.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "dephasing_time",
     "unit": "ps",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "check",
     "parameters": {
       "transition": "nu1 Q branch (the band is not named in the paper)"
     }
   }

Table \(p\. 396\), T2 at 5 atm, calculated from the linewidth by 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\: 1/\(pi c Delta nu\_R\) gives 27\.94 ps \(checked 2026\-09\-26\)\. Not a measurement\.

everall\_1987/dsigma\_H2
~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "dsigma_H2",
     "material": "H2",
     "file": "H2/everall_1987__dsigma_H2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_cross_section",
     "unit": "cm2/sr",
     "scale": 1e-29,
     "abscissa_unit": "nm",
     "use": "reproduced",
     "reproduced_from": [
       "bischel_1983"
     ],
     "parameters": {
       "transition": "vibrational Q branch (the line is not named in the paper)"
     }
   }

Table \(p\. 396\), dsigma/dOmega at the 248 nm KrF pump, used in Eq\. \(2\); the table note\: 'Cross sections for CH4, H2, N2 and O2\: ref\. \[15\]'\. Polarization and definition not stated\. Ref\. \[15\] is bischel\_1983 \(re\-pointed 2026\-09\-27\), which prints no value at 248 nm\: its single\-resonance fit \(Table 1\) gives 4\.83e\-29 \(248\.0 nm\) and 4\.79e\-29 \(248\.4 nm\), as this 4\.8\.

everall\_1987/linewidth\_H2
~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "linewidth_H2",
     "material": "H2",
     "file": "H2/everall_1987__linewidth_H2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_linewidth",
     "unit": "cm-1",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "reproduced",
     "reproduced_from": [
       "A. Owyoung, Optics Lett. 2 (1978) 91"
     ],
     "parameters": {
       "transition": "vibrational Q branch (the line is not named in the paper)",
       "width": "fwhm",
       "perturber": "self"
     }
   }

Table \(p\. 396\), the Raman linewidth Delta nu\_R at 5 atm \(the caption\: thresholds 'at 5 atm'\), FWHM\: 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\. Taken from the table note's linewidth reference; temperature not stated \(room\)\.

everall\_1987/T2\_H2
~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "T2_H2",
     "material": "H2",
     "file": "H2/everall_1987__T2_H2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "dephasing_time",
     "unit": "ps",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "check",
     "parameters": {
       "transition": "vibrational Q branch (the line is not named in the paper)"
     }
   }

Table \(p\. 396\), T2 at 5 atm, calculated from the linewidth by 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\: 1/\(pi c Delta nu\_R\) gives 1062 \(the printed 1008 corresponds to 0\.0105 cm\-1, so the 0\.01 is rounded\) ps \(checked 2026\-09\-26\)\. Not a measurement\.

everall\_1987/dsigma\_SF6
~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "dsigma_SF6",
     "material": "SF6",
     "file": "SF6/everall_1987__dsigma_SF6.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_cross_section",
     "unit": "cm2/sr",
     "scale": 1e-29,
     "abscissa_unit": "nm",
     "use": "reproduced",
     "reproduced_from": [
       "schrotter_1979"
     ],
     "parameters": {
       "transition": "nu1 (the band is not named in the paper)"
     }
   }

Table \(p\. 396\), dsigma/dOmega at the 248 nm KrF pump, used in Eq\. \(2\); the table note\: 'extrapolated from data in ref\. \[16\] assuming nu^4 scaling'\. Polarization and definition not stated\. Ref\. \[16\] is Schrotter and Klockner's Chap\. 4 \(curated as schrotter\_1979\)\. NOT REPRODUCED\: with the chapter's own definitions, dsigma/dOmega = Sigma\_j x 5\.05e\-48 cm^6/sr x \(nu\_0 \- 775 cm^\-1\)^4 at 248 nm \(nu\_0 = 40323 cm^\-1\) is 4\.1\-4\.9e\-29 cm^2/sr for SF6's Sigma\_j of 3\.3\-3\.96 \(sigma\_SF6\_\*\); the printed 6\.0e\-29 needs Sigma\_j = 4\.86, 23 % above the largest \(3\.96 at 515 nm, Clark and D'Urso\)\. Scaling an absolute 514\.5 nm value by \(nu\_0/nu\_0'\)^4 instead gives 4\.5e\-29\. Kept as printed\.

everall\_1987/linewidth\_SF6
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "linewidth_SF6",
     "material": "SF6",
     "file": "SF6/everall_1987__linewidth_SF6.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_linewidth",
     "unit": "cm-1",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "reproduced",
     "reproduced_from": [
       "P. Esherick and A. Owyoung, in: Advances in infrared and Raman spectroscopy, Vol. 9, eds. R. J. H. Clark and R. E. Hester (John Wiley and Sons, New York, 1983) ch. 3"
     ],
     "parameters": {
       "transition": "nu1 (the band is not named in the paper)",
       "width": "fwhm",
       "perturber": "self"
     }
   }

Table \(p\. 396\), the Raman linewidth Delta nu\_R at 5 atm \(the caption\: thresholds 'at 5 atm'\), FWHM\: 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\. Taken from the table note's linewidth reference; temperature not stated \(room\)\.

everall\_1987/T2\_SF6
~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "T2_SF6",
     "material": "SF6",
     "file": "SF6/everall_1987__T2_SF6.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "dephasing_time",
     "unit": "ps",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "check",
     "parameters": {
       "transition": "nu1 (the band is not named in the paper)"
     }
   }

Table \(p\. 396\), T2 at 5 atm, calculated from the linewidth by 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\: 1/\(pi c Delta nu\_R\) gives 6\.64 ps \(checked 2026\-09\-26\)\. Not a measurement\. solprop's SF6 vibrational linewidth \(constant 4\.8229e10 Hz = 1/\(pi x 6\.6 ps\), a FWHM\) is this T2, at 5 atm and held constant in density\.

everall\_1987/dsigma\_O2
~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "dsigma_O2",
     "material": "O2",
     "file": "O2/everall_1987__dsigma_O2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_cross_section",
     "unit": "cm2/sr",
     "scale": 1e-29,
     "abscissa_unit": "nm",
     "use": "reproduced",
     "reproduced_from": [
       "bischel_1983"
     ],
     "parameters": {
       "transition": "v=0-1 Q branch (not named in the paper)"
     }
   }

Table \(p\. 396\), dsigma/dOmega at the 248 nm KrF pump, used in Eq\. \(2\); the table note\: 'Cross sections for CH4, H2, N2 and O2\: ref\. \[15\]'\. Polarization and definition not stated\. Ref\. \[15\] is bischel\_1983 \(re\-pointed 2026\-09\-27\), which prints no value at 248 nm\: its single\-resonance fit \(Table 1\) gives 3\.99e\-29 \(248\.0 nm\) and 3\.94e\-29 \(248\.4 nm\), 2\-3 % above this 3\.88\.

everall\_1987/linewidth\_O2
~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "linewidth_O2",
     "material": "O2",
     "file": "O2/everall_1987__linewidth_O2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_linewidth",
     "unit": "cm-1",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "reproduced",
     "reproduced_from": [
       "J. R. Murray, J. Goldhar, D. Eimerl and A. Szöke, IEEE J. Quantum Electron. QE-15 (1979) 324"
     ],
     "parameters": {
       "transition": "v=0-1 Q branch (not named in the paper)",
       "width": "fwhm",
       "perturber": "self"
     }
   }

Table \(p\. 396\), the Raman linewidth Delta nu\_R at 5 atm \(the caption\: thresholds 'at 5 atm'\), FWHM\: 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\. Taken from the table note's linewidth reference; temperature not stated \(room\)\.

everall\_1987/T2\_O2
~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "T2_O2",
     "material": "O2",
     "file": "O2/everall_1987__T2_O2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "dephasing_time",
     "unit": "ps",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "check",
     "parameters": {
       "transition": "v=0-1 Q branch (not named in the paper)"
     }
   }

Table \(p\. 396\), T2 at 5 atm, calculated from the linewidth by 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\: 1/\(pi c Delta nu\_R\) gives 5\.90 ps \(checked 2026\-09\-26\)\. Not a measurement\.

everall\_1987/dsigma\_N2
~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "dsigma_N2",
     "material": "N2",
     "file": "N2/everall_1987__dsigma_N2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_cross_section",
     "unit": "cm2/sr",
     "scale": 1e-29,
     "abscissa_unit": "nm",
     "use": "reproduced",
     "reproduced_from": [
       "bischel_1983"
     ],
     "parameters": {
       "transition": "v=0-1 Q branch (not named in the paper)"
     }
   }

Table \(p\. 396\), dsigma/dOmega at the 248 nm KrF pump, used in Eq\. \(2\); the table note\: 'Cross sections for CH4, H2, N2 and O2\: ref\. \[15\]'\. Polarization and definition not stated\. Ref\. \[15\] is bischel\_1983 \(re\-pointed 2026\-09\-27\), which prints no value at 248 nm\: its single\-resonance fit \(Table 1\) gives 1\.54e\-29 \(248\.0 nm\) and 1\.53e\-29 \(248\.4 nm\), 1 % above this 1\.52\.

everall\_1987/linewidth\_N2
~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "linewidth_N2",
     "material": "N2",
     "file": "N2/everall_1987__linewidth_N2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "raman_linewidth",
     "unit": "cm-1",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "reproduced",
     "reproduced_from": [
       "J. R. Murray, J. Goldhar, D. Eimerl and A. Szöke, IEEE J. Quantum Electron. QE-15 (1979) 324"
     ],
     "parameters": {
       "transition": "v=0-1 Q branch (not named in the paper)",
       "width": "fwhm",
       "perturber": "self"
     }
   }

Table \(p\. 396\), the Raman linewidth Delta nu\_R at 5 atm \(the caption\: thresholds 'at 5 atm'\), FWHM\: 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\. Taken from the table note's linewidth reference; temperature not stated \(room\)\. Printed '≈1\.5' \(approximate\)\.

everall\_1987/T2\_N2
~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "T2_N2",
     "material": "N2",
     "file": "N2/everall_1987__T2_N2.csv",
     "table": "tbl_4397977c2c69",
     "quantity": "dephasing_time",
     "unit": "ps",
     "abscissa": "pressure",
     "abscissa_unit": "atm",
     "use": "check",
     "parameters": {
       "transition": "v=0-1 Q branch (not named in the paper)"
     }
   }

Table \(p\. 396\), T2 at 5 atm, calculated from the linewidth by 'T2 = 1/pi Delta nu\_R, fwhm' \(p\. 393\)\: 1/\(pi c Delta nu\_R\) gives 7\.08 \(from the approximate 1\.5\) ps \(checked 2026\-09\-26\)\. Not a measurement\.

Formulas
--------

No formulas are recorded.

Corrections
-----------

No dataset errata are recorded in this source record.

Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the :doc:`review register </register>` for the checks and decisions.