Excitation and decay of low-lying nuclear states in a dense plasma produced by a subpicosecond laser pulse

Андреев, А. В.; Volkov, R. V.; Gordienko, Vyacheslav M; Дыхне, А. М.; Kalashnikov, M. P.; Mikheev, P. M.; Nikles, P. V.; Savel’ev, A. B.; Tkalya, E. V.; Chalykh, R. A.; Chutko, O. V.

doi:10.1134/1.1342882

Cited by 35 publications

(16 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ultra-strong optical laser systems with up to few petawatt power [4][5][6][7][8] are very efficient in generating plasma environments [9], which host complex interactions between photons, electrons, ions and the atomic nucleus. Nuclear excitation in laser-generated hot plasmas involving optical lasers [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], or cold high-density plasmas [27] at the XFEL [28,29] have been under investigation. Special attention has been attracted by nuclear transitions starting from long-lived excited states.…”

mentioning

confidence: 99%

Tailoring Laser-Generated Plasmas for Efficient Nuclear Excitation by Electron Capture

Gunst

Keitel

et al. 2018

Phys. Rev. Lett.

View full text Add to dashboard Cite

The optimal parameters for nuclear excitation by electron capture in plasma environments generated by the interaction of ultra-strong optical lasers with solid matter are investigated theoretically. As a case study we consider a 4.85 keV nuclear transition starting from the long-lived 93m Mo isomer that can lead to the release of the stored 2.4 MeV excitation energy. We find that due to the complex plasma dynamics, the nuclear excitation rate and the actual number of excited nuclei do not reach their maximum at the same laser parameters. The nuclear excitation achievable with a high-power optical laser is up to twelve and up to six orders of magnitude larger than the values predicted for direct resonant and secondary plasma-mediated excitation at the x-ray free electron laser, respectively. Our results show that the experimental observation of the nuclear excitation of 93m Mo and the subsequent release of stored energy should be possible at laser facilities available today.Novel coherent light sources open unprecedented possibilities for the field of laser-matter interactions [1]. The X-ray Free Electron Laser (XFEL) [2,3] for instance can drive low-energy electromagnetic transitions in nuclei. Ultra-strong optical laser systems with up to few petawatt power [4][5][6][7][8] are very efficient in generating plasma environments [9], which host complex interactions between photons, electrons, ions and the atomic nucleus. Nuclear excitation in laser-generated hot plasmas involving optical lasers [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], or cold high-density plasmas [27] at the XFEL [28,29] have been under investigation. Special attention has been attracted by nuclear transitions starting from long-lived excited states. Such states are also known as nuclear isomers and are particularly interesting due to their potential to store large amounts of energy over long periods of time [30][31][32][33][34][35][36][37]. A typical example is 93m Mo at 2.4 MeV, for which an additional excitation of only 4.85 keV could lead to the depletion of the isomer and release on demand of the stored energy.For both optical-and x-ray laser-generated plasmas, the process of nuclear excitation by electron capture (NEEC) [38,39] into the atomic shell has proven to have a significant contribution. As secondary process in the cold plasma environment generated by the interaction of the XFEL with solid-state targets, NEEC can exceed the direct nuclear photoexcitation by six orders of magnitude [28,29] for the 4.85 keV excitation starting from the 93m Mo isomeric state. In this Letter, we show that by tailoring optical-laser-generated plasmas to harness maximum nuclear excitation via NEEC, a further six orders of magnitude increase in the nuclear excitation and subsequent isomer depletion compared to the case of cold XFEL-generated plasmas can be reached. As an interesting point, we find that due to the complexity of the processes involved, the plasma and correspondingly laser parameters for reaching the maximal NEEC ra...

show abstract

mentioning

confidence: 99%

Tailoring Laser-Generated Plasmas for Efficient Nuclear Excitation by Electron Capture

Gunst

Keitel

et al. 2018

Phys. Rev. Lett.

View full text Add to dashboard Cite

show abstract

“…The same situation characterizes the search for excitation and decay of the first isomeric state of 181 Ta. The only positive results were reported by Andreev et al (2000) who studied the activation of 181 Ta in two experiments with different pico-and femtosecond lasers. The isomer population was estimated through the analysis of the signal detected by a scintillation detector or by a microchannel plate (MCP) coupled to a CCD camera.…”

Section: Experimental Approach To Investigation Of Low-energy Nuclearmentioning

confidence: 70%

“…In most of hitherto published data, the nuclear level corresponding to the E1 transition in 181 Ta is characterized by a moderate excitation energy of about 6.2 keV, lifetime t 07 ms (with complementary level width G T~7 Â 10 211 eV), and high internal electron conversion coefficient a ¼ 70.5. The uncertainty in the value of the resonance energy 6238 eV stated in Nuclear Data Sheets is about +20 eV (Tuli, 2007), reported lifetimes of the excited nuclear state scatter between 6.05 and 9.4 ms (Andreev et al, 2000;Mouchel et al, 1981;Letokhov & Yukov, 1994). The variations in the position, transition energy and lifetime of the excited nuclear level can be attributed to experimental errors, to approximations in theoretical models used, and partly also to the configuration of the atomic electronic shell interlinked with the nucleus level structure.…”

Section: Experimental Approach To Investigation Of Low-energy Nuclearmentioning

confidence: 96%

See 1 more Smart Citation

Low-energy nuclear transitions in subrelativistic laser-generated plasmas

et al. 2008

View full text Add to dashboard Cite

The aim of the reported research is to contribute to investigation of new processes and methods interlinking nuclear and laser-plasma physics. With respect to requirements of nuclear experiments at medium-size high-power lasers, the selection of proper candidates for studying the excitation and decay of low-lying nuclear states is reviewed. An experimental approach to the identification of low-energy nuclear transitions is discussed, simple estimates of the 181 Ta excitation yield in the laser-generated plasma provide a theoretical basis for planning future work. First tests and results of the experiments at the laser facility PALS are presented.

show abstract

“…On this nucleus, the only positive results hitherto published [11] report on X-ray measurements of the 181 Ta decay by using two different pulse-duration lasers; however, recent experiments trying to verify these results [12] were not successful. Therefore, in addition to carrying out feasibility tests of operation of various experimental arrays including active detection systems (see below) in the extreme conditions (detection of weak signals in high electromagnetic and radiation background), the purpose of the present pilot investigation was to estimate upper limits for observation of this controversial phenomenon, thus contributing to discussions concerning the feasibility of experiments directed to nuclear studies at laser intensities producing subrelativistic plasmas.…”

Section: Ta: Experimental Testsmentioning

confidence: 89%

Search for low-energy nuclear transitions in laser-produced plasma

et al. 2006

View full text Add to dashboard Cite

The possibility to excite low-energy nuclear states using laser induced plasma on the Prague Asterix Laser System PALS is investigated. This medium-energy high-power facility yields interaction intensities at the level of 10 16 ÷ 10 17 Wcm −2 thus producing subrelativistic plasmas with electron temperature of the order of 1 ÷ 10 keV. Based on a systematic survey of suitable candidate nuclei, the search for the 6.238 keV excitation and decay in 181 Ta has been initiated. Tests and preliminary operation of detecting systems including active detectors are reported. 29.30.Kv, 42.55.Vc, 1 Sub-relativistic plasma-nuclear interactions Studies of photo-nuclear reactions induced by high-power lasers have become one of the most intensively developing disciplines of contemporary high-energydensity physics [1]. While ultra-intense laser systems generate relativistic electrons (which, primarily after their conversion to high-energy rays, may initiate photonuclear processes) and energetic neutrons, protons, and heavy ions capable of inducing fusion reactions, the laser-matter interactions at intensities up to 10 16 ÷ 10 17 W cm −2 (available at medium-size laser systems such as the Prague Asterix Laser System PALS [2]) produce subrelativistic plasmas with much lower electron temperature, typically 1 ÷ 10 keV. Even these low-energy electrons should be sufficient to excite (either directly or indirectly via bremsstrahlung or characteristic X-ray emission from hot dense plasma) the low-lying nuclear levels. PACS

show abstract

Excitation and decay of low-lying nuclear states in a dense plasma produced by a subpicosecond laser pulse

Cited by 35 publications

References 8 publications

Tailoring Laser-Generated Plasmas for Efficient Nuclear Excitation by Electron Capture

Tailoring Laser-Generated Plasmas for Efficient Nuclear Excitation by Electron Capture

Low-energy nuclear transitions in subrelativistic laser-generated plasmas

Search for low-energy nuclear transitions in laser-produced plasma

Contact Info

Product

Resources

About