| 1. |
- Badelek, B, et al.
(författare)
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The photon collider at TESLA
- 2004
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Ingår i: International Journal of Modern Physics A. - 0217-751X. ; 19:30, s. 5097-5186
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Forskningsöversikt (refereegranskat)abstract
- High energy photon colliders (gammagamma,gammae) are based on e(-)e(-) linear colliders where high energy photons are produced using Compton scattering of laser light on high energy electrons just before the interaction point. This paper is a part of the Technical Design Report of the linear collider TESLA.(1) Physics program, possible parameters and some technical aspects of the photon collider at TESLA are discussed.
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| 2. |
- Ter-Avetisyan, S., et al.
(författare)
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Absolute extreme ultraviolet yield from femtosecond-laser-excited Xe clusters
- 2001
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Ingår i: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - 1063-651X .- 1095-3787. ; 6403:3
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Tidskriftsartikel (refereegranskat)abstract
- Large Xe clusters (10(5)-10(6) atoms per cluster) have been irradiated with ultrashort (50 fs) and high-intensity (similar to2 x 10(18) W/cm(2)) pulses from a Ti:sapphire multi-TW laser at 800 nm wavelength. Scaling and absolute yield measurements of extreme ultraviolet (EUV) emission in a wavelength range between 7 and 15 nm in combination with cluster target characterization have been used for yield optimization. Maximum emission as a function of the backing pressure and a spatial emission anisotropy covering a factor of two at optimized yields is discussed with a simple model of the source geometry and EUV-radiation absorption. Circularly polarized laser light instead of linear polarization results in a factor of 2.5 higher emission in the 11 to 15 nm wavelength range. This indicates the initial influence of optical-field ionization for the interaction parameter range used and contrasts to collisional heating that seems to influence preferentially higher ionization. Absolute emission efficiency at 13.4 nm of up to 0.5% in 2 pi sr and 2.2% bandwidth has been obtained.
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| 3. |
- Legall, H., et al.
(författare)
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Compact X-ray microscope for the water window based on a high brightness laser plasma source
- 2012
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Ingår i: Optics Express. - 1094-4087. ; 20:16, s. 18362-18369
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Tidskriftsartikel (refereegranskat)abstract
- We present a laser plasma based x-ray microscope for the water window employing a high-average power laser system for plasma generation. At 90 W laser power a brightness of 7.4 x 10(11) photons/(s x sr x mu m(2)) was measured for the nitrogen Ly alpha line emission at 2.478 nm. Using a multilayer condenser mirror with 0.3 % reflectivity 10(6) photons/(mu m(2) x s) were obtained in the object plane. Microscopy performed at a laser power of 60 W resolves 40 nm lines with an exposure time of 60 s. The exposure time can be further reduced to 20 s by the use of new multilayer condenser optics and operating the laser at its full power of 130 W.
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| 4. |
- Schnurer, M., et al.
(författare)
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Influence of laser pulse width on absolute EUV-yield from Xe-clusters
- 2001
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Ingår i: European Physical Journal D. - : Springer Science and Business Media LLC. - 1434-6060 .- 1434-6079. ; 14:3, s. 331-335
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Tidskriftsartikel (refereegranskat)abstract
- Using 50 fs (similar to 2 x 10(18) W/cm(2)) and 2 ps (similar to 5 x 10(16) W/cm(2)) pulses from a Ti:Sa multi-TW laser at 800 nm wavelength large Xe-clusters (10(5)...10(6) atoms per cluster) have been excited. Absolute yield measurements of EUV-emission in a wavelength range between 10 nm and 15 nm in combination with cluster target variation were carried out. The ps-laser pulse has resulted in about 30% enhanced and spatially more uniform EUV-emission compared to fs-laser excitation. Circularly polarized laser light instead of linear polarization results in enhanced emission which is probably caused by electrons gaining higher energies by the polarization dependent optical field ionization process. An absolute emission efficiency at 13.4 nm of up to 0.8% in 2 pi sr and 2.2% bandwidth has been obtained.
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| 5. |
- Antel, C., et al.
(författare)
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Feebly-interacting particles : FIPs 2022 Workshop Report
- 2023
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Ingår i: European Physical Journal C. - : Springer. - 1434-6044 .- 1434-6052. ; 83:12
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Forskningsöversikt (refereegranskat)abstract
- Particle physics today faces the challenge of explaining the mystery of dark matter, the origin of matter over anti-matter in the Universe, the origin of the neutrino masses, the apparent fine-tuning of the electro-weak scale, and many other aspects of fundamental physics. Perhaps the most striking frontier to emerge in the search for answers involves new physics at mass scales comparable to familiar matter, below the GeV-scale, or even radically below, down to sub-eV scales, and with very feeble interaction strength. New theoretical ideas to address dark matter and other fundamental questions predict such feebly interacting particles (FIPs) at these scales, and indeed, existing data provide numerous hints for such possibility. A vibrant experimental program to discover such physics is under way, guided by a systematic theoretical approach firmly grounded on the underlying principles of the Standard Model. This document represents the report of the FIPs 2022 workshop, held at CERN between the 17 and 21 October 2022 and aims to give an overview of these efforts, their motivations, and the decadal goals that animate the community involved in the search for FIPs.
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| 6. |
- Beck, M., et al.
(författare)
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A pulse-train laser driven XUV source for picosecond pump-probe experiments in the water window
- 2001
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Ingår i: Optics Communications. - 0030-4018 .- 1873-0310. ; 190:06-jan, s. 317-326
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Tidskriftsartikel (refereegranskat)abstract
- We describe the development of a table top soft X-ray source based on a laser produced plasma. The plasma is produced by a Nd:YLF pulse-train laser which delivers pulse trains of up to 400 pulses each of about 25 ps duration, Number and energy of the micropulses are fully computer controlled adjustable for an optimum interaction with a rotating solid target. Spectral, spatial and temporal characteristics of the X-ray emission from Mylar and copper targets have been studied. A calibrated back-illuminated CCD camera together with a slit grating spectrograph were utilized for the measurement of the absolute soft X-ray photon fluxes. The temporal measurements were performed using a streak camera while the plasma size was measured with a zone plate. An application of the system in a X-ray absorption experiment is shown, The advantages of the system in view of possible optical pump and soft X-ray probe experiments will be discussed.
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| 7. |
- Busch, S., et al.
(författare)
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Ion acceleration with ultrafast lasers
- 2003
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 82:19, s. 3354-3356
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Tidskriftsartikel (refereegranskat)abstract
- Hot-electron confinement can build up fields capable of accelerating ions up to MeV energies when an ultrashort 35-fs laser pulse at similar to2x10(18) W/cm(2) interacts with a small spherical target. Singly charged ions with different masses have similar energies. A simple phenomenological model describes how ultrashort and less-energy-consumptive pulses drive ions to MeV energies. The energetic and spatial-emission characteristics of protons, deuterons and oxygen ions released from water and heavy-water droplets of similar to15 mum in size was determined for this interaction scenario.
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| 8. |
- Gaudino, Mario, et al.
(författare)
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Outcomes by sex in the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial.
- 2024
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Ingår i: EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology. - 1969-6213.
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Tidskriftsartikel (refereegranskat)abstract
- In the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial, among participants with stable coronary artery disease, the risk of cardiac events was similar between an invasive (INV) strategy of angiography and coronary revascularisation and a conservative (CON) strategy of initial medical therapy alone. Outcomes according to participant sex were not reported.We aimed to analyse the outcomes of ISCHEMIA by participant sex.We evaluated 1) the association between participant sex and the likelihood of undergoing revascularisation for participants randomised to the INV arm; 2) the risk of the ISCHEMIA primary composite outcome (cardiovascular death, any myocardial infarction [MI] or rehospitalisation for unstable angina, heart failure or resuscitated cardiac arrest) by participant sex; and 3) the contribution of the individual primary outcome components to the composite outcome by participant sex.Of 5,179 randomised participants, 1,168 (22.6%) were women. Female sex was independently associated with a lower likelihood of revascularisation when assigned to the INV arm (adjusted odds ratio 0.75, 95% confidence interval [CI]: 0.57-0.99; p=0.04). The INV versus CON effect on the primary composite outcome was similar between sexes (women: hazard ratio [HR] 0.96, 95% CI: 0.70-1.33; men: HR 0.90, 95% CI: 0.76-1.07; pinteraction=0.71). The contribution of the individual components to the composite outcome was similar between sexes except for procedural MI, which was significantly lower in women (9/151 [5.9%]) than men (67/519 [12.9%]; p=0.01).In ISCHEMIA, women assigned to the INV arm were less likely to undergo revascularisation than men. The effect of an INV versus CON strategy was consistent by sex, but women had a significantly lower contribution of procedural MI to the primary outcome.
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| 9. |
- Ludewig, Kristin, et al.
(författare)
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Phenology and morphology of the invasive legume Lupinus polyphyllus along a latitudinal gradient in Europe
- 2022
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Ingår i: NeoBiota. - : Pensoft Publishers. - 1619-0033 .- 1314-2488. ; 78
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Tidskriftsartikel (refereegranskat)abstract
- Plant phenology, i. e. the timing of life cycle events, is related to individual fitness and species distributionranges. Temperature is one of the most important drivers of plant phenology together with day length.The adaptation of their phenology may be important for the success of invasive plant species. The presentstudy aims at understanding how the performance and the phenology of the invasive legume Lupinuspolyphyllus vary with latitude. We sampled data across a >2000 km latitudinal gradient from Centralto Northern Europe. We quantified variation in phenology of flowering and fruiting of L. polyphyllususing >1600 digital photos of inflorescences from 220 individual plants observed weekly at 22 sites. Theday of the year at which different phenological phases were reached, increased 1.3–1.8 days per degreelatitude, whereas the growing degree days (gdd) required for these phenological phases decreased 5–16 gddper degree latitude. However, this difference disappeared, when the day length of each day included inthe calculation of gdd was considered. The day of the year of the earliest and the latest climatic zone toreach any of the three studied phenological phases differed by 23–30 days and temperature requirementsto reach these stages differed between 62 and 236 gdd. Probably, the invasion of this species will furtherincrease in the northern part of Europe over the next decades due to climate warming. For invasive speciescontrol, our results suggest that in countries with a large latitudinal extent, the mowing date should shiftby ca. one week per 500 km at sites with similar elevations.
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| 10. |
- Ludewig, Kristin, et al.
(författare)
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Phenology of Lupinus polyphyllus from Central to Northern Europe
- 2022
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Annan publikationabstract
- Plant phenology, i. e. the timing of life cycle events, is related to individual fitness and species distribution ranges. Among the environmental factors, phenology is mostly driven by temperature and day length. Rapid adaptation of their phenology may also be important for the success of invasive plant species. Our main aim was to understand how the performance, timing, and temperature dependence of the phenology of the invasive legume Lupinus polyphyllus varies with latitude. L. polyphyllus is one of the most frequent invasive species in Europe, and the gained information may help to make management more effective by adjustments to latitude and phenology.Methods:We quantified variation in phenology across a >2000 km latitudinal gradient from Central to Northern Europe. We sampled data of flowering and fruiting of L. polyphyllus using >1600 digital photos of inflorescences from 220 individual plants observed weekly at 22 locations. We calculated the accumulated growing degree days for each observation date at each site from the temperature data of the meteorological stations, which are listed in the metadata of the dataset.
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| 11. |
- Redfors, Björn, et al.
(författare)
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Outcomes According to Coronary Revascularization Modality in the ISCHEMIA Trial.
- 2024
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Ingår i: Journal of the American College of Cardiology. - 1558-3597. ; 83:5, s. 549-558
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Tidskriftsartikel (refereegranskat)abstract
- In the ISCHEMIA trial, the risk of ischemic events was similar in patients with stable coronary artery disease treated with an invasive (INV) strategy of angiography and percutaneous (PCI) or surgical (CABG) coronary revascularization and a conservative (CON) strategy of initial medical therapy.To analyze separately the outcomes of INV patients treated with PCI or CABG.Patients without preceding primary outcome events were categorized as INV-PCI or INV-CABG from the time of revascularization. The ISCHEMIA primary outcome (composite of cardiovascular death, protocol-defined myocardial infarction (MI) or hospitalization for unstable angina, heart failure or resuscitated cardiac arrest) was used.Among INV-CABG patients, primary outcome events occurred in 84/512 (16.4%) at median follow-up of 2.85 years; 48 events (57.1%) occurred within 30 days after CABG, including 40 procedural MIs; among INV-PCI patients, primary outcome events occurred in 147/1500 (9.8%) at median follow-up of 2.94 years; 31 of which (21.1%) within 30 days after PCI, including 23 procedural MIs. In comparison, 352/2591 (13.6%) CON patients had primary outcome events at median follow-up 3.2 years, 22 of which (6.3%) within 30 days of randomization. The adjusted primary outcome risks (HR [95%CI]) were higher after both CABG and PCI within 30 days (16.25 (11.44-23.07) and 2.99 (1.97-4.53)) and lower thereafter (0.63 (0.44-0.89) and 0.66(0.53-0.82)).In ISCHEMIA, early revascularization by PCI and CABG was associated with higher early risks and lower long-term risks of cardiovascular events compared with CON. The early risk was greatest after CABG, due to protocol-defined procedural MIs.
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| 12. |
- Sandner, Sigrid, et al.
(författare)
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Association of Dual Antiplatelet Therapy With Ticagrelor With Vein Graft Failure After Coronary Artery Bypass Graft Surgery: A Systematic Review and Meta-analysis.
- 2022
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Ingår i: JAMA. - 1538-3598. ; 328:6, s. 554-562
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Tidskriftsartikel (refereegranskat)abstract
- The role of ticagrelor with or without aspirin after coronary artery bypass graft surgery remains unclear.To compare the risks of vein graft failure and bleeding associated with ticagrelor dual antiplatelet therapy (DAPT) or ticagrelor monotherapy vs aspirin among patients undergoing coronary artery bypass graft surgery.MEDLINE, Embase, and Cochrane Library databases from inception to June 1, 2022, without language restriction.Randomized clinical trials (RCTs) comparing the effects of ticagrelor DAPT or ticagrelor monotherapy vs aspirin on saphenous vein graft failure.Individual patient data provided by each trial were synthesized into a combined data set for independent analysis. Multilevel logistic regression models were used.The primary analysis assessed the incidence of saphenous vein graft failure per graft (primary outcome) in RCTs comparing ticagrelor DAPT with aspirin. Secondary outcomes were saphenous vein graft failure per patient and Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding events. A supplementary analysis included RCTs comparing ticagrelor monotherapy with aspirin.A total of 4 RCTs were included in the meta-analysis, involving 1316 patients and 1668 saphenous vein grafts. Of the 871 patients in the primary analysis, 435 received ticagrelor DAPT (median age, 67 years [IQR, 60-72 years]; 65 women [14.9%]; 370 men [85.1%]) and 436 received aspirin (median age, 66 years [IQR, 61-73 years]; 63 women [14.5%]; 373 men [85.5%]). Ticagrelor DAPT was associated with a significantly lower incidence of saphenous vein graft failure (11.2%) per graft than was aspirin (20%; difference, -8.7% [95% CI, -13.5% to -3.9%]; OR, 0.51 [95% CI, 0.35 to 0.74]; P < .001) and was associated with a significantly lower incidence of saphenous vein graft failure per patient (13.2% vs 23.0%, difference, -9.7% [95% CI, -14.9% to -4.4%]; OR, 0.51 [95% CI, 0.35 to 0.74]; P < .001). Ticagrelor DAPT (22.1%) was associated with a significantly higher incidence of BARC type 2, 3, or 5 bleeding events than was aspirin (8.7%; difference, 13.3% [95% CI, 8.6% to 18.0%]; OR, 2.98 [95% CI, 1.99 to 4.47]; P < .001), but not BARC type 3 or 5 bleeding events (1.8% vs 1.8%, difference, 0% [95% CI, -1.8% to 1.8%]; OR, 1.00 [95% CI, 0.37 to 2.69]; P = .99). Compared with aspirin, ticagrelor monotherapy was not significantly associated with saphenous vein graft failure (19.3% vs 21.7%, difference, -2.6% [95% CI, -9.1% to 3.9%]; OR, 0.86 [95% CI, 0.58 to 1.27]; P = .44) or BARC type 2, 3, or 5 bleeding events (8.9% vs 7.3%, difference, 1.7% [95% CI, -2.8% to 6.1%]; OR, 1.25 [95% CI, 0.69 to 2.29]; P = .46).Among patients undergoing coronary artery bypass graft surgery, adding ticagrelor to aspirin was associated with a significantly decreased risk of vein graft failure. However, this was accompanied by a significantly increased risk of clinically important bleeding.
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| 13. |
- Sandner, Sigrid, et al.
(författare)
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One-month DAPT with ticagrelor and aspirin for patients undergoing coronary artery bypass grafting: rationale and design of the randomised, multicentre, double-blind, placebo-controlled ODIN trial.
- 2024
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Ingår i: EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology. - 1969-6213. ; 20:5
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Tidskriftsartikel (refereegranskat)abstract
- The optimal antiplatelet strategy after coronary artery bypass graft (CABG) surgery in patients with chronic coronary syndromes (CCS) is unclear. Adding the P2Y12 inhibitor, ticagrelor, to low-dose aspirin for 1 year is associated with a reduction in graft failure, particularly saphenous vein grafts, at the expense of an increased risk of clinically important bleeding. As the risk of thrombotic graft failure and ischaemic events is highest early after CABG surgery, a better risk-to-benefit profile may be attained with short-term dual antiplatelet therapy followed by single antiplatelet therapy. The One Month Dual Antiplatelet Therapy With Ticagrelor in Coronary Artery Bypass Graft Patients (ODIN) trial is a prospective, randomised, double-blind, placebo-controlled, international, multicentre study of 700 subjects that will evaluate the effect of short-term dual antiplatelet therapy with ticagrelor plus low-dose aspirin after CABG in patients with CCS. Patients will be randomised 1:1 to ticagrelor 90 mg twice daily or matching placebo, in addition to aspirin 75-150 mg once daily for 1 month; after the first month, antiplatelet therapy will be continued with aspirin alone. The primary endpoint is a hierarchical composite of all-cause death, stroke, myocardial infarction, revascularisation and graft failure at 1 year. The key secondary endpoint is a hierarchical composite of all-cause death, stroke, myocardial infarction, Bleeding Academic Research Consortium (BARC) type 3 bleeding, revascularisation and graft failure at 1 year (net clinical benefit). ODIN will report whether the addition of ticagrelor to low-dose aspirin for 1 month after CABG reduces ischaemic events and provides a net clinical benefit in patients with CCS. (ClinicalTrials.gov: NCT05997693).
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| 14. |
- Vogt, Ulrich, et al.
(författare)
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Influence of laser intensity and pulse duration on the extreme ultraviolet yield from a water jet target laser plasma
- 2001
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 79:15, s. 2336-2338
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Tidskriftsartikel (refereegranskat)abstract
- Extreme ultraviolet (EUV) emission in the 11-15 nm wavelength range from a thin liquid water jet target under illumination with a high repetition rate, high average power laser (Nd-YLF) has been studied. To find the optimum conversion efficiency of laser light into EUV radiation, different laser parameters were applied. The laser intensity was varied between 10(11) and 10(15) W/cm(2), and pulse duration in the range from 30 ps to 3 ns. A maximum conversion efficiency of 0.12% in 2.2% bandwidth and 4 pi steradian at 13 nm was achieved at a repetion rate of 250 kHz, and a strong dependence of the conversion efficiency on both laser intensity and pulse duration was found.
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