asghar_2020
===========

H\. Asghar, N\. K\. Piracha, R\. Ali and M\. A\. Baig, "Measurements of experimental transition probabilities of 3p5 4p \-\> 3p5 4s arrays in neutral argon", Appl\. Opt\. 59, 4240\-4246 \(2020\)

`Source record <https://github.com/LupoLab/optmat/blob/main/src/optmat/data/sources/asghar_2020.toml>`__ · :doc:`Catalogue </the-data/sources>` · :doc:`Review register </register>`

DOI: `10\.1364/ao\.393053 <https://doi.org/10.1364/ao.393053>`__

**Source kind:** measurement

**Recorded technique:** Emission branching fractions of the Ar I 4p\-4s lines \(650\-1100 nm\) from a commercial argon hollow\-cathode lamp \(Photron; 3 mm cathode, 5\-8 Torr, 1\-10 mA DC\), recorded with an Ocean Optics HR4000 CCD spectrometer \(0\.2 nm FWHM at 600 nm, intensity calibrated by the manufacturer\); absolute A\_ik = BF\_i / tau\_i \(Eq\. 2\) with upper\-level lifetimes quoted from Chang and Setser \(eight levels\) and Erman and Huldt \(4p'\[1/2\]0, 4p\[1/2\]0\)\.

**Materials in structured entries:** Ar

**Dataset quantities:** radiative\_lifetime, transition\_probability

**Contents:** 3 datasets; 0 formulas.

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

Identity\: Applied Optics, volume 59, number 14, 10 May 2020, pp\. 4240\-4246, H\. Asghar, N\. K\. Piracha, R\. Ali, M\. A\. Baig \(Quaid\-i\-Azam University, Islamabad; John Carroll University\), "Measurements of experimental transition probabilities of 3p5 4p \-\> 3p5 4s arrays in neutral argon", received 18 March 2020 \(first page of the vector PDF\)\.

Taken \(TC\-1011's quantities\)\: Table 1's measured A of the 27 lines with a value \(transition\_probability, primary\) and the two sets of upper\-level lifetimes the A are normalised to, quoted from Chang and Setser and from Erman and Huldt \(radiative\_lifetime, reproduced\)\. tools/extract/asghar\_2020\.py\.

NOT TAKEN\: Table 1's comparison columns \(NIST, which is wiese\_1989's set, TC\-1012; Garstang and Van Blerkom's LS, JcK and IC calculations, J\. Opt\. Soc\. Am\. 55, 1054 \(1965\)\)\: other works' values\. Table 2's \(p\. 4245\) line strengths S \(a\.u\.\) and absorption f\: conversions of Table 1's A by Eqs\. \(3\) and \(4\) \(S = 4\.935e\-19 lambda^3 g\_k A, f = 1\.499e\-16 \(g\_k/g\_i\) lambda^2 A, lambda in angstrom\), no new information; the script checks them, and all S and all but three f follow from Table 1's A within 3 % with the printed air wavelengths\: f of 714\.71 nm \(0\.003 printed; 0\.0055 from the paper's A, 0\.0029 from NIST's\), 751\.47 nm \(0\.111; 0\.134 from the paper's A, 0\.113 from NIST's\) and 747\.2 nm \(2\.09E\-4 printed for a line with no A; NIST's A gives 1\.84e\-4\) follow NIST's A rather than the paper's\. Table 3 \(J\-file sum rule\)\: sums of Table 2's S; its 4p\[1/2\]1 row prints S = 0 for 1148\.81 nm, which Tables 1 and 2 leave empty \(the library's cells of Table 3's first block are merged and unusable; read from the image\)\.

Levels\: the paper's JcK labels nl\[K\]\_J \(a prime for the 2P1/2 core\) are NIST's configuration 3s2\.3p5\.\(2P\*\<3/2\>\)\.nl or \(2P\*\<1/2\>\)\.nl, term 2\[K\] and J; Paschen as printed, 1s5, 1s4, 1s3, 1s2 = 4s\[3/2\]2, 4s\[3/2\]1, 4s'\[1/2\]0, 4s'\[1/2\]1 and 2p1\-2p10 = 4p'\[1/2\]0, 4p'\[1/2\]1, 4p'\[3/2\]2, 4p'\[3/2\]1, 4p\[1/2\]0, 4p\[3/2\]2, 4p\[3/2\]1, 4p\[5/2\]2, 4p\[5/2\]3, 4p\[1/2\]1 \(the same mapping as wiese\_1989\)\. Every row's printed wavelength \(air, two decimals\) is NIST's air wavelength of its labelled pair within 0\.006 nm, but 747\.2 nm \(NIST 747\.117 nm\)\. Two lower levels are misprinted, both in rows without a value \(not taken\)\: 747\.2 nm prints 4s'\[3/2\]1 \(no such level; 4s\[3/2\]1, Paschen 1s4 as printed\) and 857\.8 nm prints 4s\[1/2\]1 \(4s'\[1/2\]1, 1s2 as printed\)\.

Comparison with wiese\_1989 \(Table IV, TC\-1012\) and NIST ASD \(Ar\_I\_lines\_nir\.tsv, TC\-985\), all 27 lines\: ratio paper / Wiese mean 1\.058, median 1\.010, mean \|deviation\| 12\.8 %, from 0\.817 \(922\.45 nm\) to 1\.92 \(714\.71 nm, 1\.20 against 0\.625e6 s\-1\); against NIST mean 1\.058, 0\.822 to 1\.905 \(NIST's 4p\-4s A are Wiese's, rounded\)\. 16 of 27 agree with Wiese within the paper's uncertainty, 22 within twice it; outside twice it\: 772\.42 nm \(17\.68 against 11\.7; the paper blames the unresolved 772\.38 nm\), 727\.29, 706\.72, 714\.71 and 922\.45 nm\. The 12 lines with A \>= 1e7 s\-1\: mean 1\.060, 0\.905 \(912\.30 nm\) to 1\.511 \(772\.42 nm\)\. The column "NIST \[24\]" is NIST's A to the printed digits for all 29 rows that print one\.

Radiative widths\: 1/sum A of the printed A per 4p level is 23\.00 \(2p1\), 23\.00, 29\.40, 30\.82, 21\.00, 27\.01, 29\.31, 32\.80, 30\.10, 42\.18 ns \(2p10\), against wiese\_1989's 22\.35, 28\.39, 28\.93, 30\.17, 24\.88, 29\.04, 29\.70, 31\.01, 30\.21, 39\.22 ns\. The lines the paper lacks are weak \(NIST\: 747\.117 nm 0\.022e6, 1148\.811 nm 0\.19e6 s\-1, 857\.806 nm \< 0\.001e6 s\-1\), so Eq\. \(2\) requires sum A tau = 1\: it holds within 2 % for 2p5\-2p10 \(1\.017 for 2p7, the rest within 0\.1 %\) but is 0\.870, 1\.152, 0\.939 and 1\.077 for 2p1\-2p4 with the printed lifetimes \(20, 26\.5, 27\.6, 33\.2 ns\); 2p1's and 2p2's printed A both sum to 1/\(23\.00 ns\)\. The paper does not say why; for 2p2 the printed 26\.5 ns would give A 13 % lower \(772\.42 nm 15\.3, nearer NIST's 11\.7 but still off\)\. The per\-level widths therefore carry no information of their own\: for 2p5\-2p10 they are the quoted lifetimes, for 2p1\-2p4 an unexplained scale\. Only the branching fractions are the paper's measurement\.

Independence\: the branching fractions are an independent measurement \(own lamp, spectrometer and manufacturer's intensity calibration\) of the quantities Wiese et al\. averaged from Nick and Helbig and from Shumaker and Popenoe\. The normalisation is not Wiese's\: Chang and Setser's lifetimes \(J\. Chem\. Phys\. 69, 3885 \(1978\)\) for eight levels, Erman and Huldt's \(Phys\. Scr\. 17, 473 \(1978\)\) for 2p1 and 2p5, where Wiese et al\. scaled to Quadfasel and Helbig's; but Chang and Setser's eight values are the same as those wiese\_1989 lists in its Table II \(26\.5, 27\.6, 33\.2, 27\.0, 29\.8, 32\.8, 30\.1, 42\.2 ns\), which Wiese et al\. compared and did not adopt\. The A of 2p5\-2p10 are therefore independent of Wiese in their branching and in their scale; 2p1\-2p4 are independent in their branching, with an unstated scale\.

Other data the paper cites, not in the library\: R\. S\. F\. Chang and D\. W\. Setser, J\. Chem\. Phys\. 69, 3885 \(1978\) \(radiative lifetimes and two\-body deactivation rate constants of Ar 4p and 4p' levels\: quenching data relevant to OEP 8\); P\. Erman and S\. Huldt, Phys\. Scr\. 17, 473 \(1978\) \(4p and 5p lifetimes and radiation trapping\); R\. A\. Nodwell, J\. Meyer and T\. Jacobson, JQSRT 10, 335 \(1970\) \(absolute 4p\-4s A\); O\. Zatsarinny and K\. Bartschat, Phys\. Scr\. T134, 014020 \(2009\) \(B\-spline f values\)\. The cells of Table 1 were checked against the table image \(2026\-10\-12\)\.

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

Datasets
--------

asghar\_2020/A\_4p\_4s
~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "A_4p_4s",
     "material": "Ar",
     "file": "Ar/asghar_2020__A_4p_4s.csv",
     "table": "tbl_8164cd4b15b2",
     "quantity": "transition_probability",
     "unit": "1/s",
     "scale": 1000000.0,
     "abscissa": "label",
     "use": "primary",
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "notation": "racah"
     }
   }

Table 1 \(p\. 4243\), column 'Present Work', A \(1e6 s\-1\)\: the 27 Ar I 4p\-4s lines with a value \(747\.2, 857\.8 and 1148\.81 nm print '\-'\)\. A = BF / tau \(Eq\. 2\), the branching fractions measured in a hollow\-cathode lamp \(5\-8 Torr, 1\-10 mA\), the lifetimes quoted \(datasets lifetime\_chang\_1978, lifetime\_erman\_1978\)\. Each row's uncertainty is the printed absolute \+\- \(738\.40 nm prints '8\.23 0\.68', the \+\- lost\)\: 'The uncertainties in the measured line intensities \[5\-7 %\] and reported lifetimes have been added' \(p\. 4243\), level not stated\. Rows are the printed air wavelengths \(nm\); x is upper\-lower in the paper's Racah notation\. Eq\. \(2\) fails for 2p1\-2p4 with the printed lifetimes \(record notes\); the paper attributes the 51 % excess of 772\.42 nm over NIST to its blend with 772\.38 nm at 0\.2 nm resolution \(p\. 4243\), so 772\.42 and 772\.38 nm are doubtful\.

asghar\_2020/lifetime\_chang\_1978
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "lifetime_chang_1978",
     "material": "Ar",
     "file": "Ar/asghar_2020__lifetime_chang_1978.csv",
     "table": "tbl_8164cd4b15b2",
     "quantity": "radiative_lifetime",
     "unit": "ns",
     "abscissa": "label",
     "use": "reproduced",
     "reproduced_from": [
       "R. S. F. Chang and D. W. Setser, J. Chem. Phys. 69, 3885 (1978)"
     ],
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "method": "measured: time-resolved laser-induced fluorescence (as the citing paper describes Chang and Setser's work)"
     }
   }

Table 1 \(p\. 4243\), column 'Lifetimes tau \(ns\)', footnote b \(Chang and Setser, Ref\. 22\)\: the lifetimes of 4p'\[1/2\]1, 4p'\[3/2\]2, 4p'\[3/2\]1, 4p\[3/2\]2, 4p\[3/2\]1, 4p\[5/2\]2, 4p\[5/2\]3 and 4p\[1/2\]1 \(2p2\-2p4, 2p6\-2p10\), 26\.5\-42\.2 ns, with the printed absolute uncertainties \(the percentage printed in parentheses is their ratio\)\. The same values as wiese\_1989's Table II column 'Chang and Setser' \(not taken there\)\. Rows and x are the levels\.

asghar\_2020/lifetime\_erman\_1978
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. code-block:: text

   {
     "id": "lifetime_erman_1978",
     "material": "Ar",
     "file": "Ar/asghar_2020__lifetime_erman_1978.csv",
     "table": "tbl_8164cd4b15b2",
     "quantity": "radiative_lifetime",
     "unit": "ns",
     "abscissa": "label",
     "use": "reproduced",
     "reproduced_from": [
       "P. Erman and S. Huldt, Phys. Scr. 17, 473 (1978)"
     ],
     "uncertainty": {
       "column": true,
       "level": "not stated"
     },
     "parameters": {
       "method": "measured: high-frequency deflection technique (the citing paper's words, p. 4242, which also say Erman and Huldt 'calculated' them)"
     }
   }

Table 1 \(p\. 4243\), column 'Lifetimes tau \(ns\)', footnote a \(Erman and Huldt, Ref\. 21\), for the two levels Chang and Setser lack\: 4p'\[1/2\]0 \(2p1\) 20 \+\- 2 ns and 4p\[1/2\]0 \(2p5\) 21 \+\- 3 ns\. wiese\_1989's Table II gives 21\.7 and 24\.4 ns \(Quadfasel and Helbig\) for these levels\. Rows and x are the levels\.

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.