augst_1989 ========== S\. Augst, D\. Strickland, D\. D\. Meyerhofer, S\. L\. Chin and J\. H\. Eberly, "Tunneling ionization of noble gases in a high\-intensity laser field", Phys\. Rev\. Lett\. 63, 2212 \(1989\) `Source record `__ · :doc:`Catalogue ` · :doc:`Review register ` DOI: `10\.1103/physrevlett\.63\.2212 `__ **Source kind:** measurement **Recorded technique:** Ion yields of He, Ne, Ar, Kr and Xe \(charge states up to Xe12\+\) against peak intensity, mid\-1e13 to mid\-1e16 W/cm^2\: chirped\-pulse\-amplified Nd\:glass laser, 1\.053 um, ~1 ps \(bandwidth 30 A as printed here\), f/6 focusing \(20 cm lens\); intensity from energy, pulse width \(second\- and third\-order correlation, shot\-to\-shot relative width from frequency doubling\) and focal spot \(equivalent target plane\); gas backfilled to ~5e\-6 Torr; time\-of\-flight spectrometer \(800 V/cm, 30 cm drift\), microchannel plate \(pp\. 1\-2\)\. **Materials in structured entries:** None recorded. **Dataset quantities:** None recorded. **Contents:** 0 datasets; 0 formulas. Curation notes -------------- Identity checked against pdf p\. 1\. Pages are pdf pages \(1\-4 = pp\. 2212\-2215\)\. WHY NOTHING IS TAKEN\. The data are figures only\: Fig\. 1 \(p\. 2\), the approximate number of argon ions detected against peak intensity \('Similar graphs have been constructed for He, Ne, Kr, and Xe', not shown\); Fig\. 2 \(p\. 2\), the appearance intensity of every observed charge state of the five gases against the sequential ionisation potential; Fig\. 3 \(p\. 3\), calculated \(barrier\-suppression\) against experimental appearance intensities\. No appearance intensity is printed as a number\. The full data are in the companion paper augst\_1991 \(also figures only\)\. NUMBERS IN THE TEXT\. Appearance intensity\: 'the intensity at which ten ions of that species are detected' \(p\. 2\); 'the ten\-ion level corresponds to an ionization probability of ~5 x 10^\-3 for the lowest charge states' \(p\. 2\)\. Uncertainty\: 'The uncertainty in the absolute value of the intensity is approximately a factor of 2' \(p\. 1\); relative intensities among runs and gases \(mixed\-gas targets\) 'less than 25%' \(p\. 2\)\. The appearance intensities are 'as much as a factor of 10' higher than those with 50 ps pulses at the same wavelength \(L'Huillier et al\., J\. Phys\. B 16, 1363 \(1983\), ref\. 2; p\. 2\)\. ADK \(Ammosov et al\. 1986\)\: 'all of the appearance intensities are matched within the factor of 2 absolute uncertainty in the experimental intensity', but 'the deviation between experimental and predicted intensities systematically increases with decreasing atomic weight' \(p\. 3\); augst\_1991 Table 1 quantifies this as intensity shift factors\. Discrepancies with augst\_1991 \(the same laser\)\: bandwidth 30 A here against ~20 A there, f/6 here against f/5 there\. FORMULAS \(not recorded separately; the same model is augst\_1991's bsi\_threshold, in SI there\)\. Eqs\. \(4\)\-\(6\), p\. 3, Gaussian units\: V\(x\) = \-Z e^2/x \- e epsilon x; critical field epsilon^2 = E\_ion^4/\(16 e^6 Z^2\); appearance intensity I\_app = c E\_ion^4/\(128 pi e^6 Z^2\), 'Using no free parameters, excellent agreement is obtained over almost three decades of intensity for all charge states' \(p\. 3\)\. Eq\. \(2\)\: Phi\_pond \(eV\) = e^2 epsilon^2/\(4 m omega^2\) = 9\.33 x 10^\-14 I lambda^2 \(I in W/cm^2, lambda in um\)\. **Recorded bibliographic identity status:** VALIDATED\_WITH\_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents. Datasets -------- No datasets are recorded. 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 ` for the checks and decisions.