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Available in 19 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-19" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">19 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Fotoionitzaci%C3%B3" title="Fotoionització – Catalan" lang="ca" hreflang="ca" data-title="Fotoionització" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Fotoionizace" title="Fotoionizace – Czech" lang="cs" hreflang="cs" data-title="Fotoionizace" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Fotoionisatsioon" title="Fotoionisatsioon – Estonian" lang="et" hreflang="et" data-title="Fotoionisatsioon" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%81%D9%88%D8%AA%D9%88%DB%8C%D9%88%D9%86%DB%8C%D8%B2%D8%A7%D8%B3%DB%8C%D9%88%D9%86" title="فوتویونیزاسیون – Persian" lang="fa" hreflang="fa" data-title="فوتویونیزاسیون" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/F%C3%B3ta-ian%C3%BAch%C3%A1n" title="Fóta-ianúchán – Irish" lang="ga" hreflang="ga" data-title="Fóta-ianúchán" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EA%B4%91%EC%9D%B4%EC%98%A8%ED%99%94" title="광이온화 – Korean" lang="ko" hreflang="ko" data-title="광이온화" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%AB%E0%A5%8B%E0%A4%9F%E0%A5%8B-%E0%A4%86%E0%A4%AF%E0%A4%A8%E0%A5%80%E0%A4%95%E0%A4%B0%E0%A4%A3" title="फोटो-आयनीकरण – Hindi" lang="hi" hreflang="hi" data-title="फोटो-आयनीकरण" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Fotoionizzazione" title="Fotoionizzazione – Italian" lang="it" hreflang="it" data-title="Fotoionizzazione" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E5%85%89%E3%82%A4%E3%82%AA%E3%83%B3%E5%8C%96" title="光イオン化 – Japanese" lang="ja" hreflang="ja" data-title="光イオン化" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Fotoionisering" title="Fotoionisering – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Fotoionisering" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Fotoionisasjon" title="Fotoionisasjon – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Fotoionisasjon" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Fotoionlashtirish" title="Fotoionlashtirish – Uzbek" lang="uz" hreflang="uz" data-title="Fotoionlashtirish" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Fotoioniza%C3%A7%C3%A3o" title="Fotoionização – Portuguese" lang="pt" hreflang="pt" data-title="Fotoionização" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Fotoionizare" title="Fotoionizare – Romanian" lang="ro" hreflang="ro" data-title="Fotoionizare" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%A4%D0%BE%D1%82%D0%BE%D1%98%D0%BE%D0%BD%D0%B8%D0%B7%D0%B0%D1%86%D0%B8%D1%98%D0%B0" title="Фотојонизација – Serbian" lang="sr" hreflang="sr" data-title="Фотојонизација" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%92%E0%AE%B3%E0%AE%BF_%E0%AE%85%E0%AE%AF%E0%AE%A9%E0%AE%BF%E0%AE%AF%E0%AE%BE%E0%AE%95%E0%AF%8D%E0%AE%95%E0%AE%AE%E0%AF%8D" title="ஒளி அயனியாக்கம் – Tamil" lang="ta" hreflang="ta" data-title="ஒளி அயனியாக்கம்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Fotoiyonizasyon" title="Fotoiyonizasyon – Turkish" lang="tr" hreflang="tr" data-title="Fotoiyonizasyon" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A4%D0%BE%D1%82%D0%BE%D1%96%D0%BE%D0%BD%D1%96%D0%B7%D0%B0%D1%86%D1%96%D1%8F" title="Фотоіонізація – Ukrainian" lang="uk" hreflang="uk" data-title="Фотоіонізація" data-language-autonym="Українська" 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data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Ion formation via a photon interacting with a molecule or atom</div> <p class="mw-empty-elt"> </p> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Hubble_green_filaments_20150402.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/76/Hubble_green_filaments_20150402.jpg/300px-Hubble_green_filaments_20150402.jpg" decoding="async" width="300" height="142" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/76/Hubble_green_filaments_20150402.jpg/450px-Hubble_green_filaments_20150402.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/76/Hubble_green_filaments_20150402.jpg/600px-Hubble_green_filaments_20150402.jpg 2x" data-file-width="4932" data-file-height="2338" /></a><figcaption>Photoionization is the process that makes once-invisible filaments in deep space glow.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p><b>Photoionization</b> is the physical process in which an ion is formed from the interaction of a <a href="/wiki/Photon" title="Photon">photon</a> with an <a href="/wiki/Atom" title="Atom">atom</a> or <a href="/wiki/Molecule" title="Molecule">molecule</a>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Cross_section">Cross section</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photoionization&action=edit&section=1" title="Edit section: Cross section"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Not every interaction between a photon and an atom, or molecule, will result in photoionization. The probability of photoionization is related to the <a href="/wiki/Photoionisation_cross_section" title="Photoionisation cross section">photoionization cross section</a> of the species – the probability of an ionization event conceptualized as a hypothetical cross-sectional area. This cross section depends on the energy of the photon (proportional to its wavenumber) and the species being considered i.e. it depends on the structure of the molecular species. In the case of molecules, the photoionization cross-section can be estimated by examination of Franck-Condon factors between a ground-state molecule and the target ion. This can be initialized by computing the vibrations of a molecule and associated cation (post ionization) using quantum chemical software e.g. QChem. For photon energies below the ionization threshold, the photoionization cross-section is near zero. But with the development of pulsed lasers it has become possible to create extremely intense, coherent light where multi-photon ionization may occur via sequences of excitations and relaxations. At even higher intensities (around <span class="nowrap">10<sup>15</sup> – 10<sup>16</sup> W/cm<sup>2</sup></span> of infrared or visible light), <a href="/wiki/Non-perturbative" title="Non-perturbative">non-perturbative</a> phenomena such as <i>barrier suppression ionization</i><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> and <i>rescattering ionization</i><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> are observed. </p> <div class="mw-heading mw-heading2"><h2 id="Multi-photon_ionization">Multi-photon ionization</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photoionization&action=edit&section=2" title="Edit section: Multi-photon ionization"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Several photons of energy below the ionization threshold may actually combine their energies to ionize an atom. This probability decreases rapidly with the number of photons required, but the development of very intense, pulsed lasers still makes it possible. In the perturbative regime (below about 10<sup>14</sup> W/cm<sup>2</sup> at optical frequencies), the probability of absorbing <i>N</i> photons depends on the laser-light intensity <i>I</i> as <i>I</i><sup><i>N</i> </sup>.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> For higher intensities, this dependence becomes invalid due to the then occurring AC <a href="/wiki/Stark_effect" title="Stark effect">Stark effect</a>.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Resonance-enhanced_multiphoton_ionization" title="Resonance-enhanced multiphoton ionization">Resonance-enhanced multiphoton ionization</a> (REMPI) is a technique applied to the <a href="/wiki/Spectroscopy" title="Spectroscopy">spectroscopy</a> of <a href="/wiki/Atom" title="Atom">atoms</a> and small <a href="/wiki/Molecule" title="Molecule">molecules</a> in which a <a href="/wiki/Tunable_laser" title="Tunable laser">tunable laser</a> can be used to access an <a href="/wiki/Excited_state" title="Excited state">excited intermediate state</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (November 2023)">citation needed</span></a></i>]</sup> </p><p><a href="/wiki/Above-threshold_ionization" title="Above-threshold ionization">Above-threshold ionization</a> (ATI)<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> is an extension of multi-photon ionization where even more photons are absorbed than actually would be necessary to ionize the atom. The excess energy gives the released electron higher <a href="/wiki/Kinetic_energy" title="Kinetic energy">kinetic energy</a> than the usual case of just-above threshold ionization. More precisely, the system will have multiple peaks in its <a href="/wiki/Photoelectron_spectrum" class="mw-redirect" title="Photoelectron spectrum">photoelectron spectrum</a> which are separated by the photon energies, indicating that the emitted electron has more kinetic energy than in the normal (lowest possible number of photons) ionization case. The electrons released from the target will have approximately an integer number of photon-energies more kinetic energy.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (September 2011)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="Tunnel_ionization">Tunnel ionization</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photoionization&action=edit&section=3" title="Edit section: Tunnel ionization"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>When either the laser intensity is further increased or a longer wavelength is applied as compared with the regime in which multi-photon ionization takes place, a quasi-stationary approach can be used and results in the distortion of the atomic potential in such a way that only a relatively low and narrow barrier between a <a href="/wiki/Bound_state" title="Bound state">bound state</a> and the continuum states remains. Then, the electron can <a href="/wiki/Quantum_tunnelling" title="Quantum tunnelling">tunnel through</a> or for larger distortions even overcome this barrier. These phenomena are called <a href="/wiki/Tunnel_ionization" title="Tunnel ionization">tunnel ionization</a> and <a href="/w/index.php?title=Over-the-barrier_ionization&action=edit&redlink=1" class="new" title="Over-the-barrier ionization (page does not exist)">over-the-barrier ionization</a>, respectively.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (November 2023)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photoionization&action=edit&section=4" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Ion_source" title="Ion source">Ion source</a></li> <li><a href="/wiki/Radiolysis" title="Radiolysis">Radiolysis</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photoionization&action=edit&section=5" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation news cs1"><a rel="nofollow" class="external text" href="http://www.spacetelescope.org/news/heic1507/">"Hubble finds ghosts of quasars past"</a>. <i>ESA/Hubble Press Release</i><span class="reference-accessdate">. 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"Tunneling and barrier-suppression ionization of atoms and ions in a laser radiation field". <i><a href="/wiki/Physics-Uspekhi" title="Physics-Uspekhi">Physics-Uspekhi</a></i>. <b>41</b> (5): 469–485. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1998PhyU...41..469D">1998PhyU...41..469D</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1070%2FPU1998v041n05ABEH000393">10.1070/PU1998v041n05ABEH000393</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:94362581">94362581</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Physics-Uspekhi&rft.atitle=Tunneling+and+barrier-suppression+ionization+of+atoms+and+ions+in+a+laser+radiation+field&rft.volume=41&rft.issue=5&rft.pages=469-485&rft.date=1998&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A94362581%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1070%2FPU1998v041n05ABEH000393&rft_id=info%3Abibcode%2F1998PhyU...41..469D&rft.aulast=Delone&rft.aufirst=N.+B.&rft.au=Krainov%2C+V.+P.&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDichiara2005" class="citation conference cs1">Dichiara, A.; et al. 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"Multiphoton absorption above ionization threshold by atoms in strong laser fields". <i><a href="/wiki/Journal_of_the_Optical_Society_of_America_B" class="mw-redirect" title="Journal of the Optical Society of America B">Journal of the Optical Society of America B</a></i>. <b>2</b> (3): 491. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1985JOSAB...2..486D">1985JOSAB...2..486D</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1364%2FJOSAB.2.000486">10.1364/JOSAB.2.000486</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+the+Optical+Society+of+America+B&rft.atitle=Multiphoton+absorption+above+ionization+threshold+by+atoms+in+strong+laser+fields&rft.volume=2&rft.issue=3&rft.pages=491&rft.date=1985&rft_id=info%3Adoi%2F10.1364%2FJOSAB.2.000486&rft_id=info%3Abibcode%2F1985JOSAB...2..486D&rft.aulast=Deng&rft.aufirst=Z.&rft.au=Eberly%2C+J.+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFProtopapasKeitelKnight1997" class="citation journal cs1">Protopapas, M; Keitel, C H; Knight, P L (1 April 1997). "Atomic physics with super-high intensity lasers". <i>Reports on Progress in Physics</i>. <b>60</b> (4): 389–486. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1997RPPh...60..389P">1997RPPh...60..389P</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F0034-4885%2F60%2F4%2F001">10.1088/0034-4885/60/4/001</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:250856994">250856994</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Reports+on+Progress+in+Physics&rft.atitle=Atomic+physics+with+super-high+intensity+lasers&rft.volume=60&rft.issue=4&rft.pages=389-486&rft.date=1997-04-01&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A250856994%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1088%2F0034-4885%2F60%2F4%2F001&rft_id=info%3Abibcode%2F1997RPPh...60..389P&rft.aulast=Protopapas&rft.aufirst=M&rft.au=Keitel%2C+C+H&rft.au=Knight%2C+P+L&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAgostini1979" class="citation journal cs1">Agostini, P.; et al. (1979). <a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRevLett.42.1127">"Free-Free Transitions Following Six-Photon Ionization of Xenon Atoms"</a>. <i><a href="/wiki/Physical_Review_Letters" title="Physical Review Letters">Physical Review Letters</a></i>. <b>42</b> (17): 1127–1130. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1979PhRvL..42.1127A">1979PhRvL..42.1127A</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRevLett.42.1127">10.1103/PhysRevLett.42.1127</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Physical+Review+Letters&rft.atitle=Free-Free+Transitions+Following+Six-Photon+Ionization+of+Xenon+Atoms&rft.volume=42&rft.issue=17&rft.pages=1127-1130&rft.date=1979&rft_id=info%3Adoi%2F10.1103%2FPhysRevLett.42.1127&rft_id=info%3Abibcode%2F1979PhRvL..42.1127A&rft.aulast=Agostini&rft.aufirst=P.&rft_id=https%3A%2F%2Fdoi.org%2F10.1103%252FPhysRevLett.42.1127&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Photoionization&action=edit&section=6" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin" style=""> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFUwe_BeckerDavid_Allen_Shirley1996" class="citation book cs1">Uwe Becker; David Allen Shirley (1 January 1996). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=m9chfY8jtxYC"><i>VUV and Soft X-Ray Photoionization</i></a>. Springer Science & Business Media. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-306-45038-9" title="Special:BookSources/978-0-306-45038-9"><bdi>978-0-306-45038-9</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=VUV+and+Soft+X-Ray+Photoionization&rft.pub=Springer+Science+%26+Business+Media&rft.date=1996-01-01&rft.isbn=978-0-306-45038-9&rft.au=Uwe+Becker&rft.au=David+Allen+Shirley&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Dm9chfY8jtxYC&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCheuk-Yiu_Ng1991" class="citation book cs1">Cheuk-Yiu Ng (1991). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=bbg_Xkbm9BcC"><i>Vacuum Ultraviolet Photoionization and Photodissociation of Molecules and Clusters</i></a>. <a href="/wiki/World_Scientific" title="World Scientific">World Scientific</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-981-02-0430-3" title="Special:BookSources/978-981-02-0430-3"><bdi>978-981-02-0430-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Vacuum+Ultraviolet+Photoionization+and+Photodissociation+of+Molecules+and+Clusters&rft.pub=World+Scientific&rft.date=1991&rft.isbn=978-981-02-0430-3&rft.au=Cheuk-Yiu+Ng&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Dbbg_Xkbm9BcC&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJoseph_Berkowitz1979" class="citation book cs1">Joseph Berkowitz (1979). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=POeHAAAAIAAJ"><i>Photoabsorption, photoionization, and photoelectron spectroscopy</i></a>. <a href="/wiki/Academic_Press" title="Academic Press">Academic Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-12-091650-4" title="Special:BookSources/978-0-12-091650-4"><bdi>978-0-12-091650-4</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Photoabsorption%2C+photoionization%2C+and+photoelectron+spectroscopy&rft.pub=Academic+Press&rft.date=1979&rft.isbn=978-0-12-091650-4&rft.au=Joseph+Berkowitz&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DPOeHAAAAIAAJ&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFV._S._Letokhov1987" class="citation book cs1">V. S. Letokhov (1987). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=dOXvAAAAMAAJ"><i>Laser photoionization spectroscopy</i></a>. Academic Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-12-444320-4" title="Special:BookSources/978-0-12-444320-4"><bdi>978-0-12-444320-4</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Laser+photoionization+spectroscopy&rft.pub=Academic+Press&rft.date=1987&rft.isbn=978-0-12-444320-4&rft.au=V.+S.+Letokhov&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DdOXvAAAAMAAJ&rfr_id=info%3Asid%2Fen.wikipedia.org%3APhotoionization" class="Z3988"></span></li></ul> </div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline 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title="Fourier-transform infrared spectroscopy">FT-IR</a></li> <li><a href="/wiki/Raman_spectroscopy" title="Raman spectroscopy">Raman</a></li> <li><a href="/wiki/Resonance_Raman_spectroscopy" title="Resonance Raman spectroscopy">Resonance Raman</a></li> <li><a href="/wiki/Rotational_spectroscopy" title="Rotational spectroscopy">Rotational</a></li> <li><a href="/wiki/Rotational%E2%80%93vibrational_spectroscopy" title="Rotational–vibrational spectroscopy">Rotational–vibrational</a></li> <li><a href="/wiki/Molecular_vibration" title="Molecular vibration">Vibrational</a></li> <li><a href="/wiki/Vibrational_circular_dichroism" title="Vibrational circular dichroism">Vibrational circular dichroism</a></li> <li><a href="/wiki/Nuclear_resonance_vibrational_spectroscopy" title="Nuclear resonance vibrational spectroscopy">Nuclear resonance vibrational spectroscopy</a></li> <li><a href="/wiki/Vibrational_spectroscopy_of_linear_molecules" title="Vibrational spectroscopy of linear molecules">Vibrational spectroscopy of linear molecules</a></li> <li><a href="/wiki/Thermal_infrared_spectroscopy" title="Thermal infrared spectroscopy">Thermal infrared spectroscopy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">UV–Vis–NIR "Optical"</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ultraviolet%E2%80%93visible_spectroscopy" title="Ultraviolet–visible spectroscopy">Ultraviolet–visible</a></li> <li><a href="/wiki/Fluorescence_spectroscopy" title="Fluorescence spectroscopy">Fluorescence</a> <ul><li><a href="/wiki/Cold_vapour_atomic_fluorescence_spectroscopy" title="Cold vapour atomic fluorescence spectroscopy">Cold vapour atomic</a></li></ul></li> <li><a href="/wiki/Vibronic_spectroscopy" title="Vibronic spectroscopy">Vibronic</a></li> <li><a href="/wiki/Near-infrared_spectroscopy" title="Near-infrared spectroscopy">Near-infrared</a></li> <li><a href="/wiki/Resonance-enhanced_multiphoton_ionization" title="Resonance-enhanced multiphoton ionization">Resonance-enhanced multiphoton ionization</a> (REMPI)</li> <li><a href="/wiki/Raman_spectroscopy" title="Raman spectroscopy">Raman</a> <ul><li><a href="/wiki/Coherent_anti-Stokes_Raman_spectroscopy" title="Coherent anti-Stokes Raman spectroscopy">Coherent anti-Stokes</a></li></ul></li> <li><a href="/wiki/Raman_optical_activity" title="Raman optical activity">Raman optical activity</a></li> <li><a href="/wiki/Laser-induced_breakdown_spectroscopy" title="Laser-induced breakdown spectroscopy">Laser-induced breakdown</a></li> <li><a href="/wiki/Atomic_spectroscopy" title="Atomic spectroscopy">Atomic</a> <ul><li><a href="/wiki/Atomic_emission_spectroscopy" title="Atomic emission spectroscopy">emission</a> <ul><li><a href="/wiki/Glow-discharge_optical_emission_spectroscopy" title="Glow-discharge optical emission spectroscopy">Glow-discharge optical</a></li></ul></li> <li><a href="/wiki/Atomic_absorption_spectroscopy" title="Atomic absorption spectroscopy">absorption</a></li></ul></li> <li><a href="/wiki/Cavity_ring-down_spectroscopy" title="Cavity ring-down spectroscopy">Cavity ring-down spectroscopy</a></li> <li><a href="/wiki/Saturated_absorption_spectroscopy" title="Saturated absorption spectroscopy">Saturated absorption spectroscopy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">X-ray and Gamma ray</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray_spectroscopy" title="X-ray spectroscopy">X-ray</a> <ul><li><a href="/wiki/Energy-dispersive_X-ray_spectroscopy" title="Energy-dispersive X-ray spectroscopy">Energy-dispersive</a></li> <li><a href="/wiki/X-ray_emission_spectroscopy" title="X-ray emission spectroscopy">Emission</a></li> <li><a href="/wiki/Extended_X-ray_absorption_fine_structure" title="Extended X-ray absorption fine structure">Extended X-ray absorption fine structure</a></li></ul></li> <li><a href="/wiki/Gamma_spectroscopy" title="Gamma spectroscopy">Gamma</a></li> <li><a href="/wiki/M%C3%B6ssbauer_spectroscopy" title="Mössbauer spectroscopy">Mössbauer</a> <ul><li><a href="/wiki/Conversion_electron_M%C3%B6ssbauer_spectroscopy" title="Conversion electron Mössbauer spectroscopy">Conversion electron</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Electron</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Photoemission_spectroscopy" title="Photoemission spectroscopy">Photoelectron/photoemission</a> <ul><li><a href="/wiki/X-ray_photoelectron_spectroscopy" title="X-ray photoelectron spectroscopy">X-ray</a></li> <li><a href="/wiki/Ultraviolet_photoelectron_spectroscopy" title="Ultraviolet photoelectron spectroscopy">UV</a></li> <li><a href="/wiki/Angle-resolved_photoemission_spectroscopy" title="Angle-resolved photoemission spectroscopy">Angle-resolved</a></li> <li><a href="/wiki/Two-photon_photoelectron_spectroscopy" title="Two-photon photoelectron spectroscopy">Two-photon</a></li></ul></li> <li><a href="/wiki/Auger_electron_spectroscopy" title="Auger electron spectroscopy">Auger</a></li> <li><a href="/wiki/Electron_phenomenological_spectroscopy" title="Electron phenomenological spectroscopy">phenomenological</a></li> <li><a href="/wiki/Electron_paramagnetic_resonance" title="Electron paramagnetic resonance">paramagnetic</a></li> <li><a href="/wiki/Beta_spectroscopy" class="mw-redirect" title="Beta spectroscopy">Beta spectroscopy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Nucleon</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alpha-particle_spectroscopy" title="Alpha-particle spectroscopy">Alpha</a></li> <li><a href="/wiki/Inelastic_neutron_scattering" class="mw-redirect" title="Inelastic neutron scattering">Inelastic neutron scattering</a> <ul><li><a href="/wiki/Neutron_spin_echo" title="Neutron spin echo">Neutron spin echo</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Radiowave</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nuclear_magnetic_resonance_spectroscopy" title="Nuclear magnetic resonance spectroscopy">NMR</a> <ul><li><a href="/wiki/Two-dimensional_nuclear_magnetic_resonance_spectroscopy" title="Two-dimensional nuclear magnetic resonance spectroscopy">2D</a></li></ul></li> <li><a href="/wiki/Terahertz_spectroscopy_and_technology" title="Terahertz spectroscopy and technology">Terahertz</a></li> <li><a href="/wiki/Electron_paramagnetic_resonance" title="Electron paramagnetic resonance">ESR/EPR</a></li> <li><a href="/wiki/Ferromagnetic_resonance" title="Ferromagnetic resonance">Ferromagnetic resonance</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Others</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks hlist navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Data collection, processing</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fourier-transform_spectroscopy" title="Fourier-transform spectroscopy">Fourier-transform spectroscopy</a></li> <li><a href="/wiki/Hyperspectral_imaging" title="Hyperspectral imaging">Hyperspectral imaging</a></li> <li><a href="/wiki/Spectrophotometry" title="Spectrophotometry">Spectrophotometry</a></li> <li><a href="/wiki/Time_stretch_analog-to-digital_converter" class="mw-redirect" title="Time stretch analog-to-digital converter">Time-stretch</a></li> <li><a href="/wiki/Time-resolved_spectroscopy" title="Time-resolved spectroscopy">Time-resolved spectroscopy</a></li> <li><a href="/wiki/Video_spectroscopy" title="Video spectroscopy">Video spectroscopy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Measured phenomena</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acoustic_resonance_spectroscopy" title="Acoustic resonance spectroscopy">Acoustic resonance spectroscopy</a></li> <li><a href="/wiki/Circular_dichroism" title="Circular dichroism">Circular dichroism spectroscopy</a></li> <li><a href="/wiki/Deep-level_transient_spectroscopy" title="Deep-level transient spectroscopy">Deep-level transient spectroscopy</a></li> <li><a href="/wiki/Dual-polarization_interferometry" title="Dual-polarization interferometry">Dual-polarization interferometry</a></li> <li><a href="/wiki/Hadron_spectroscopy" title="Hadron spectroscopy">Hadron spectroscopy</a></li> <li><a href="/wiki/Inelastic_electron_tunneling_spectroscopy" title="Inelastic electron tunneling spectroscopy">Inelastic electron tunneling spectroscopy</a> <ul><li><a href="/wiki/Scanning_tunneling_spectroscopy" title="Scanning tunneling spectroscopy">Scanning tunneling spectroscopy</a></li></ul></li> <li><a href="/wiki/Photoacoustic_spectroscopy" title="Photoacoustic spectroscopy">Photoacoustic spectroscopy</a></li> <li><a href="/wiki/Photothermal_spectroscopy" title="Photothermal spectroscopy">Photothermal spectroscopy</a></li> <li><a href="/wiki/Pump%E2%80%93probe_spectroscopy" class="mw-redirect" title="Pump–probe spectroscopy">Pump–probe spectroscopy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Applications</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Astronomical_spectroscopy" title="Astronomical spectroscopy">Astronomical spectroscopy</a></li> <li><a href="/wiki/Force_spectroscopy" title="Force spectroscopy">Force spectroscopy</a> (a misnomer)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/Category:Spectroscopy" title="Category:Spectroscopy">Category</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="Commons page"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span> <b><a href="https://commons.wikimedia.org/wiki/Category:Spectroscopy" class="extiw" title="commons:Category:Spectroscopy">Commons</a></b></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="X-ray_science" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:X-ray_science" title="Template:X-ray science"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:X-ray_science" title="Template talk:X-ray science"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:X-ray_science" title="Special:EditPage/Template:X-ray science"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="X-ray_science" style="font-size:114%;margin:0 4em"><a href="/wiki/X-ray" title="X-ray">X-ray science</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:#e5e5ff;">Characteristics</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray" title="X-ray">X-ray</a></li> <li><a href="/wiki/Absorption_edge" title="Absorption edge">Absorption edge</a></li> <li><a href="/wiki/Moseley%27s_law" title="Moseley's law">Moseley's law</a></li> <li><a href="/wiki/Synchrotron_radiation" title="Synchrotron radiation">Synchrotron radiation</a></li> <li><a href="/wiki/Water_window" title="Water window">Water window</a></li> <li><a href="/wiki/K-edge" title="K-edge">K-edge</a></li> <li><a href="/wiki/Metal_L-edge" title="Metal L-edge">L-edge</a></li> <li><a href="/wiki/Siegbahn_notation" title="Siegbahn notation">Siegbahn notation</a></li> <li><a href="/wiki/Characteristic_X-ray" title="Characteristic X-ray">Characteristic X-ray</a></li> <li><a href="/wiki/High-energy_X-rays" title="High-energy X-rays">High-energy X-rays</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:#e5e5ff;">Sources and instruments</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray_tube" title="X-ray tube">X-ray tube</a></li> <li><a href="/wiki/Betatron" title="Betatron">Betatron</a></li> <li><a href="/wiki/Synchrotron" title="Synchrotron">Synchrotron</a></li> <li><a href="/wiki/Synchrotron_light_source" title="Synchrotron light source">Synchrotron light source</a></li> <li><a href="/wiki/Free-electron_laser" title="Free-electron laser">Free-electron laser</a></li> <li><a href="/w/index.php?title=X-ray_nanoprobe&action=edit&redlink=1" class="new" title="X-ray nanoprobe (page does not exist)">X-ray nanoprobe</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:#e5e5ff;">Interaction with matter</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Rayleigh_scattering" title="Rayleigh scattering">Rayleigh scattering</a></li> <li><a href="/wiki/Photoelectric_effect" title="Photoelectric effect">Photoelectric effect</a></li> <li><a href="/wiki/Compton_scattering" title="Compton scattering">Compton scattering</a></li> <li><a href="/wiki/Auger_effect" title="Auger effect">Auger effect</a></li> <li><a class="mw-selflink selflink">Photoionization</a></li> <li><a href="/wiki/Photodisintegration" title="Photodisintegration">Photodisintegration</a></li> <li><a href="/wiki/Radiation_damage" title="Radiation damage">Radiation damage</a></li> <li><a href="/wiki/Anomalous_X-ray_scattering" title="Anomalous X-ray scattering">Anomalous X-ray scattering</a></li> <li><a href="/wiki/X-ray_diffraction" title="X-ray diffraction">X-ray diffraction</a></li> <li><a href="/wiki/X-ray_fluorescence" title="X-ray fluorescence">X-ray fluorescence</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:#e5e5ff;">Applications</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Imaging</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray_radiography" class="mw-redirect" title="X-ray radiography">X-ray radiography</a></li> <li><a href="/wiki/Panoramic_radiograph" title="Panoramic radiograph">Panoramic radiography</a></li> <li><a href="/wiki/Tomosynthesis" title="Tomosynthesis">Tomosynthesis</a></li> <li><a href="/wiki/Coherent_diffraction_imaging" title="Coherent diffraction imaging">CDI</a></li> <li><a href="/wiki/CT_scan" title="CT scan">CT</a> <ul><li><a href="/wiki/Helical_CT" class="mw-redirect" title="Helical CT">Helical CT</a></li> <li><a href="/w/index.php?title=X-ray_induced_acoustic_computed_tomography&action=edit&redlink=1" class="new" title="X-ray induced acoustic computed tomography (page does not exist)">XACT</a></li></ul></li> <li><a href="/wiki/Soft_x-ray_microscopy" class="mw-redirect" title="Soft x-ray microscopy">Soft x-ray microscopy</a></li> <li><a href="/wiki/Phase-contrast_X-ray_imaging" title="Phase-contrast X-ray imaging">XPCI</a></li> <li><a href="/wiki/Scanning_transmission_X-ray_microscopy" title="Scanning transmission X-ray microscopy">STXM</a></li> <li><a href="/wiki/Ptychography" title="Ptychography">Ptychography</a></li> <li><a href="/wiki/Diffraction_tomography" title="Diffraction tomography">Diffraction tomography</a> <ul><li><a href="/wiki/X-ray_diffraction_computed_tomography" title="X-ray diffraction computed tomography">XDCT</a></li> <li><a href="/w/index.php?title=Diffraction_Contrast_Tomography&action=edit&redlink=1" class="new" title="Diffraction Contrast Tomography (page does not exist)">DCT</a></li> <li><a href="/wiki/Three-dimensional_X-ray_diffraction" title="Three-dimensional X-ray diffraction">3DXRD</a></li></ul></li> <li><a href="/wiki/X-Ray_Fluorescence_Imaging" class="mw-redirect" title="X-Ray Fluorescence Imaging">X-Ray Fluorescence Imaging</a></li> <li><a href="/w/index.php?title=X-ray_holography&action=edit&redlink=1" class="new" title="X-ray holography (page does not exist)">X-ray holography</a></li> <li><a href="/wiki/X-ray_telescope" title="X-ray telescope">X-ray telescope</a></li> <li><a href="/wiki/Dark-field_X-ray_microscopy" title="Dark-field X-ray microscopy">DFXM</a></li> <li><a href="/wiki/Dual-energy_X-ray_absorptiometry" title="Dual-energy X-ray absorptiometry">DXA</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Spectroscopy</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray_absorption_spectroscopy" title="X-ray absorption spectroscopy">XAS</a></li> <li><a href="/wiki/X-ray_photoelectron_spectroscopy" title="X-ray photoelectron spectroscopy">XPS</a></li> <li><a href="/wiki/Angle-resolved_photoemission_spectroscopy" title="Angle-resolved photoemission spectroscopy">ARPES</a></li> <li><a href="/wiki/Auger_electron_spectroscopy" title="Auger electron spectroscopy">AES</a></li> <li><a href="/wiki/Extended_X-ray_absorption_fine_structure" title="Extended X-ray absorption fine structure">EXAFS</a></li> <li><a href="/wiki/X-ray_absorption_near_edge_structure" title="X-ray absorption near edge structure">XANES</a></li> <li><a href="/wiki/Energy-dispersive_X-ray_spectroscopy" title="Energy-dispersive X-ray spectroscopy">EDS</a></li> <li><a href="/wiki/X-ray_fluorescence_holography" title="X-ray fluorescence holography">XFH</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/X-ray_scattering_techniques" title="X-ray scattering techniques">Scattering</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray_crystallography" title="X-ray crystallography">X-ray crystallography</a></li> <li><a href="/wiki/X-ray_diffraction" title="X-ray diffraction">X-ray diffraction</a></li> <li><a href="/wiki/Backscatter_X-ray" title="Backscatter X-ray">Backscatter X-ray</a></li> <li><a href="/wiki/Small-angle_X-ray_scattering" title="Small-angle X-ray scattering">SAXS</a></li> <li><a href="/wiki/Grazing-incidence_small-angle_scattering" title="Grazing-incidence small-angle scattering">GISAXS</a></li> <li><a href="/wiki/Wide-angle_X-ray_scattering" title="Wide-angle X-ray scattering">WAXS</a></li> <li><a href="/wiki/X-ray_reflectivity" title="X-ray reflectivity">X-ray reflectivity</a></li> <li><a href="/wiki/Resonant_inelastic_X-ray_scattering" title="Resonant inelastic X-ray scattering">RIXS</a></li> <li><a href="/wiki/X-ray_Raman_scattering" title="X-ray Raman scattering">XRS</a></li> <li><a href="/wiki/Fluctuation_X-ray_scattering" title="Fluctuation X-ray scattering">XS</a></li> <li><a href="/wiki/Energy-dispersive_X-ray_diffraction" title="Energy-dispersive X-ray diffraction">EDXRD</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Others</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/X-ray_astronomy" title="X-ray astronomy">X-ray astronomy</a> <ul><li><a href="/wiki/History_of_X-ray_astronomy" title="History of X-ray astronomy">History</a></li></ul></li> <li><a href="/wiki/X-ray_lithography" title="X-ray lithography">X-ray lithography</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"><style data-mw-deduplicate="TemplateStyles:r1038841319">.mw-parser-output .tooltip-dotted{border-bottom:1px dotted;cursor:help}</style></div><div role="navigation" class="navbox authority-control" aria-label="Navbox" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control databases</a>: National <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a 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