Preparation and characterization of micro-nano engineered targets for high-power laser experiments

[EN] The continuous development of ultra-fast high-power lasers (HPL) technology with the ability of working at unprecedented repetition rates, between 1 and 10 Hz, is raising the target needs for experiments in the different areas of interest to the HPL community. Many target designs can be conceived according to specific scientific issues, however to guarantee manufacturing abilities that enable large number production and still allow for versatility in the design is the main barrier in the exploitation of these high repetition rate facilities. Here, we have applied MEMS based manufacturing processes for this purpose. In particular, we have focused on the fabrication and characterization of submicrometric conductive membranes embedded in a silicon frame. These kinds of solid targets are used for laser-driven particle acceleration through the so-called Target Normal Sheath Acceleration mechanism (TNSA). They were obtained by top-down fabrication alternating pattern transfer, atomic layer deposition, and selective material etching. The adaptability of the approach is then analyzed and discussed by evaluating different properties of targets for use in laser-driven particle acceleration experiments. These characteristics include the surface properties of membranes after fabrication and the high density of the target array. Finally, we were able to show their efficiency for laser-driven proton acceleration in a series of experiments with a 3 TW table-top laser facility, achieving stable proton acceleration up to 2 MeV.The authors highly appreciate the collaboration of Radosys (Budapest) which provided CR-39 detector material, etching bath, and readout equipment. This project has been financed by the Spanish Ministry for Economy and Competitiveness within the Retos-Colaboracion 2015 initiative, ref. RTC-2015-3278-1. P. Mur has received a grant of the Garantia Juvenil 2015 program. This work has made use of the Spanish ICTS Network MICRONANOFABS partially supported by MEINCOM.Zaffino, R.; Seimetz, M.; Quirión, D.; Ruiz-De La Cruz, A.; Sánchez, I.; Mur, P.; Benlliure, J.... (2018). Preparation and characterization of micro-nano engineered targets for high-power laser experiments. Microelectronic Engineering. 194:67-70. https://doi.org/10.1016/j.mee.2018.03.011S677019

Efficient proton acceleration from a 3 TW table-top laser interacting with submicrometric mass-produced solid targets

[EN] Thin layer membranes with controllable features and material arrangements are often used as target materials for laser driven particle accelerators. Reduced cost, large scale fabrication of such membranes with high reproducibility, and good stability are central for the efficient production of proton beams. These characteristics are of growing importance in the context of advanced laser light sources where increased repetition rates boost the need for consumable targets with design and properties adjusted to study the different phenomena arising in ultra-intense laser-plasma interaction. Wepresent the fabrication of sub-micrometric thin-layer gold or aluminum membranes in a silicon wafer frame by using nano/micro-electro-mechanical-system (N/MEMS) processing which are suitable for rapid patterning and machining of many samples at the same time and allowing for high-throughput production of targets for laser-driven acceleration. Obtained targets were tested for laserproton acceleration through the Target Normal Sheath Acceleration mechanism (TNSA) in a series of experiments carried out on a purpose-made table-top Ti:Sa running at 3 TW peak power and 10 Hz diode pump rate with a contrast over ASE of 10(8)The authors highly appreciate the collaboration of Radosys (Budapest) which provided CR-39 detector material, etching bath, and readout equipment. This project has been financed by the Spanish Ministry for Economy and Competitiveness within the Retos-Colaboracion 2015 initiative, ref. RTC-2015-3278-1. P Mur has received a grant of the Garantia Juvenil 2015 program. This work has made use of the Spanish ICTS Network MICRONANOFABS partially supported by MEINCOM.Zaffino, R.; Seimetz, M.; Ruiz-De La Cruz, A.; Sánchez, I.; Mur, P.; Quirión, D.; Bellido-Millán, PJ.... (2018). Efficient proton acceleration from a 3 TW table-top laser interacting with submicrometric mass-produced solid targets. Journal of Physics Communications. 2(4):1-6. https://doi.org/10.1088/2399-6528/aabc25S1624Borghesi, M., Campbell, D. H., Schiavi, A., Haines, M. G., Willi, O., MacKinnon, A. J., … Bulanov, S. (2002). Electric field detection in laser-plasma interaction experiments via the proton imaging technique. Physics of Plasmas, 9(5), 2214-2220. doi:10.1063/1.1459457Ledingham, K., Bolton, P., Shikazono, N., & Ma, C.-M. (2014). Towards Laser Driven Hadron Cancer Radiotherapy: A Review of Progress. Applied Sciences, 4(3), 402-443. doi:10.3390/app4030402Spindloe, C., Arthur, G., Hall, F., Tomlinson, S., Potter, R., Kar, S., … Tolley, M. K. (2016). High volume fabrication of laser targets using MEMS techniques. Journal of Physics: Conference Series, 713, 012002. doi:10.1088/1742-6596/713/1/012002Schomburg, W. K. (2011). Thin Films. RWTHedition, 9-20. doi:10.1007/978-3-642-19489-4_4Bellido, P., Lera, R., Seimetz, M., Cruz, A. R. la, Torres-Peirò, S., Galán, M., … Benlloch, J. M. (2017). Characterization of protons accelerated from a 3 TW table-top laser system. Journal of Instrumentation, 12(05), T05001-T05001. doi:10.1088/1748-0221/12/05/t05001Mayer, M. (1999). SIMNRA, a simulation program for the analysis of NRA, RBS and ERDA. AIP Conference Proceedings. doi:10.1063/1.59188Ceccotti, T., Lévy, A., Popescu, H., Réau, F., D’Oliveira, P., Monot, P., … Martin, P. (2007). Proton Acceleration with High-Intensity Ultrahigh-Contrast Laser Pulses. Physical Review Letters, 99(18). doi:10.1103/physrevlett.99.185002Dollar, F., Reed, S. A., Matsuoka, T., Bulanov, S. S., Chvykov, V., Kalintchenko, G., … Maksimchuk, A. (2013). High-intensity laser-driven proton acceleration enhancement from hydrogen containing ultrathin targets. Applied Physics Letters, 103(14), 141117. doi:10.1063/1.4824361Neely, D., Foster, P., Robinson, A., Lindau, F., Lundh, O., Persson, A., … McKenna, P. (2006). Enhanced proton beams from ultrathin targets driven by high contrast laser pulses. Applied Physics Letters, 89(2), 021502. doi:10.1063/1.2220011Green, J. S., Carroll, D. C., Brenner, C., Dromey, B., Foster, P. S., Kar, S., … Zepf, M. (2010). Enhanced proton flux in the MeV range by defocused laser irradiation. New Journal of Physics, 12(8), 085012. doi:10.1088/1367-2630/12/8/085012Giuffrida, L., Svensson, K., Psikal, J., Dalui, M., Ekerfelt, H., Gallardo Gonzalez, I., … Margarone, D. (2017). Manipulation of laser-accelerated proton beam profiles by nanostructured and microstructured targets. Physical Review Accelerators and Beams, 20(8). doi:10.1103/physrevaccelbeams.20.08130

Wafer-scale fabrication of target arrays for stable generation of proton beams by laser-plasma interaction

[EN] Large-scale fabrication of targets for laser-driven acceleration of ion beams is a prerequisite to establish suitable applications, and to keep up with the challenge of increasing repetition rate of currently available high-power lasers. Here we present manufacturing and test results of large arrays of solid targets for TNSA laser-driven ion acceleration. By applying micro-electro-mechanical-system (MEMS) based methods allowing for parallel processing of thousands of targets on a single Si wafer, sub-micrometric, thin-layer metallic membranes were fabricated by combining photolithography, physical and chemical vapor deposition, selective etching, and Si micromachining. These structures were characterized by using optical and atomic force microscopy. Their performance for the production of laser-driven proton beams was tested on a purpose-made table-top Ti:Sapphire laser system running at 3 TW peak power with a contrast over ASE of 108. We have performed several test series achieving maximum proton energy values around 2 MeV.This work has made use of the Spanish ICTS Network MICRONANOFABS partially supported by MEINCOM. This project has been financed by the Spanish Ministry for Economy and Competitiveness within the Retos- Colaboración 2015 initiative, ref. RTC-2015-3278-1. P. Mur has received a grant of the Garantía Juvenil 2015 program.Zaffino, R.; Seimetz, M.; Ruiz-De La Cruz, A.; Sánchez, I.; Mur, P.; Bellido-Millán, PJ.; Lera, R.... (2018). Wafer-scale fabrication of target arrays for stable generation of proton beams by laser-plasma interaction. Journal of Physics: Conference Series (Online). 1079. https://doi.org/10.1088/1742-6596/1079/1/012007S0120071079Abedi, S., Dorranian, D., Abari, M. E., & Shokri, B. (2011). Relativistic effects in the interaction of high intensity ultra-short laser pulse with collisional underdense plasma. Physics of Plasmas, 18(9), 093108. doi:10.1063/1.3633529Antici, P., Fuchs, J., d’ Humières, E., Lefebvre, E., Borghesi, M., Brambrink, E., … Pépin, H. (2007). Energetic protons generated by ultrahigh contrast laser pulses interacting with ultrathin targets. Physics of Plasmas, 14(3), 030701. doi:10.1063/1.2480610Ceccotti, T., Lévy, A., Popescu, H., Réau, F., D’Oliveira, P., Monot, P., … Martin, P. (2007). Proton Acceleration with High-Intensity Ultrahigh-Contrast Laser Pulses. Physical Review Letters, 99(18). doi:10.1103/physrevlett.99.18500

Coulomb dissociation of N 20,21

Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N20,21 are reported. Relativistic N20,21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N19(n,γ)N20 and N20(n,γ)N21 excitation functions and thermonuclear reaction rates have been determined. The N19(n,γ)N20 rate is up to a factor of 5 higher at

Coulomb dissociation of O-16 into He-4 and C-12

We measured the Coulomb dissociation of O-16 into He-4 and C-12 within the FAIR Phase-0 program at GSI Helmholtzzentrum fur Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section O-16(alpha,gamma)C-12, which is the time reversed reaction to C-12(alpha,gamma)O-16. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the (RB)-B-3 setup were necessary to cope with the high-intensity O-16 beam. All tracking detectors were designed to let the unreacted O-16 ions pass, while detecting the C-12 and He-4

Coulomb dissociation of 16O into 4He and 12C

We measured the Coulomb dissociation of 16O into 4He and 12C at the R3B setup in a first campaign within FAIR Phase 0 at GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt. The goal was to improve the accuracy of the experimental data for the 12C(a,?)16O fusion reaction and to reach lower center-ofmass energies than measured so far. The experiment required beam intensities of 109 16O ions per second at an energy of 500 MeV/nucleon. The rare case of Coulomb breakup into 12C and 4He posed another challenge: The magnetic rigidities of the particles are so close because of the same mass-To-charge-number ratio A/Z = 2 for 16O, 12C and 4He. Hence, radical changes of the R3B setup were necessary. All detectors had slits to allow the passage of the unreacted 16O ions, while 4He and 12C would hit the detectors' active areas depending on the scattering angle and their relative energies. We developed and built detectors based on organic scintillators to track and identify the reaction products with sufficient precision

The child creativity test (TCI): Assessing creativity through a problem finding task

Reconocimiento-No comercial-SinObraDerivadaLos tests de pensamiento divergente no atienden generalmente a la naturaleza compleja de la creatividad y se centran en el producto final o solución del problema, obviando fases previas del proceso creativo como la búsqueda y formulación del problema. El presente estudio adopta el modelo de problem-finding y plantea una nueva medida de la creatividad para ninos ˜ de educación primaria (6-12 anos). ˜ Se expone la fundamentación teórica así como el proceso de diseno, ˜ construcción y validación de la prueba a través de diferentes estudios. El Test de Creatividad Infantil (TCI) evalúa el proceso creativo a partir de una tarea estructurada en dos fases: formulación y solución del problema. El test considera no sólo el resultado final (un dibujo) sino las fases previas que llevan a alcanzarlo. Los resultados muestran una fiabilidad y validez satisfactorias de las puntuaciones de la prueba. Se concluye que el TCI tiene unas propiedades psicométricas robustas y puede ser una herramienta útil para predecir el comportamiento creativo de los ninos ˜ en educación primariaDivergent thinking tests do not generally address the complex nature of creativity but rather focus on the final product or solution of a problem, overlooking the previous stages of the creative process such as the discovery and formulation of a problem. The present study adopts the lrsquo;problem finding’ model and presents a new measure of creativity in children in primary education (6-12 years old). This paper presents the theoretical foundations as well as the process of designing, developing, and validating the test through different studies. The Child Creativity Test (TCI in Spanish) evaluates the creative process through a task structured in two stages: formulation and solution of a problem. The test considers not only the final output (a drawing), but also the previous phases that lead to it. Results show satisfactory validity and reliability of the test scores. It is concluded that the TCI has robust psychometric properties and can be a useful tool to predict creative behavior in primary school childre

Design of operating rules in complex water resources systems using historical records, expert criteria and fuzzy logic

<p>Oral presentation performed by Hector Macian-Sorribes on April 16th in the EGU General Assembly 2015.</p

Electromagnetic pulse generation in laser-proton acceleration from conductive and dielectric targets

[EN] Laser-plasma interactions at high intensities are often accompanied by emission of a strong electromagnetic pulse (EMP) interfering with particle detectors or other electronic equipment. We present experimental evidence for significant differences in noise amplitudes in laser-proton acceleration from aluminium as compared to mylar target foils. Such dissimilarities have been consistently observed throughout two series of measurements indicating that, under otherwise identical conditions, the target conductivity is the principal parameter related to EMP generation. In addition, the lateral size of the target foils correlates with the absolute noise levels. A frequency analysis combined with numerical simulations allows for an identification of several sources of radiofrequency emission in the MHz-GHz regime. Further, the temporal evolution of single frequencies on the nanosecond scale provides information on distinct excitation mechanisms.This project has been funded by Ministerio de Economia y Competitividad, reference RTC-2015-3278-1, with further support by Ministerio de Ciencia, Innovacion y Universidades, reference RTI2018-101578-B-C22.Seimetz, M.; Bellido, P.; Mur, P.; Lera, R.; Ruiz-De La Cruz, A.; Sánchez, I.; Zaffino, R.... (2020). Electromagnetic pulse generation in laser-proton acceleration from conductive and dielectric targets. Plasma Physics and Controlled Fusion. 62(11):1-9. https://doi.org/10.1088/1361-6587/abb2e5S196211Daido, H., Nishiuchi, M., & Pirozhkov, A. S. (2012). Review of laser-driven ion sources and their applications. Reports on Progress in Physics, 75(5), 056401. doi:10.1088/0034-4885/75/5/056401Macchi, A., Borghesi, M., & Passoni, M. (2013). Ion acceleration by superintense laser-plasma interaction. Reviews of Modern Physics, 85(2), 751-793. doi:10.1103/revmodphys.85.751Wilks, S. C., Langdon, A. B., Cowan, T. E., Roth, M., Singh, M., Hatchett, S., … Snavely, R. A. (2001). Energetic proton generation in ultra-intense laser–solid interactions. Physics of Plasmas, 8(2), 542-549. doi:10.1063/1.1333697Ledingham, K., Bolton, P., Shikazono, N., & Ma, C.-M. (2014). Towards Laser Driven Hadron Cancer Radiotherapy: A Review of Progress. Applied Sciences, 4(3), 402-443. doi:10.3390/app4030402Remo, J. L., Adams, R. G., & Jones, M. C. (2007). Atmospheric electromagnetic pulse propagation effects from thick targets in a terawatt laser target chamber. Applied Optics, 46(24), 6166. doi:10.1364/ao.46.006166Aspiotis, J. A., Barbieri, N., Bernath, R., Brown, C. G., Richardson, M., & Cooper, B. Y. (2006). Detection and analysis of RF emission generated by laser-matter interactions. Enabling Technologies and Design of Nonlethal Weapons. doi:10.1117/12.663822Yang, J., Li, T., Yi, T., Wang, C., Yang, M., Yang, W., … Ding, Y. (2016). Electromagnetic Pulses Generated From Laser Target Interactions at Shenguang II Laser Facility. Plasma Science and Technology, 18(10), 1044-1048. doi:10.1088/1009-0630/18/10/13Rączka, P., Dubois, J.-L., Hulin, S., Tikhonchuk, V., Rosiński, M., Zaraś-Szydłowska, A., & Badziak, J. (2017). Strong electromagnetic pulses generated in high-intensity short-pulse laser interactions with thin foil targets. Laser and Particle Beams, 35(4), 677-686. doi:10.1017/s026303461700074xRobinson, T. S., Consoli, F., Giltrap, S., Eardley, S. J., Hicks, G. S., Ditter, E. J., … Smith, R. A. (2017). Low-noise time-resolved optical sensing of electromagnetic pulses from petawatt laser-matter interactions. Scientific Reports, 7(1). doi:10.1038/s41598-017-01063-1Consoli, F., De Angelis, R., Robinson, T. S., Giltrap, S., Hicks, G. S., Ditter, E. J., … Smith, R. A. (2019). Generation of intense quasi-electrostatic fields due to deposition of particles accelerated by petawatt-range laser-matter interactions. Scientific Reports, 9(1). doi:10.1038/s41598-019-44937-2Stoeckl, C., Glebov, V. Y., Jaanimagi, P. A., Knauer, J. P., Meyerhofer, D. D., Sangster, T. C., … Norreys, P. A. (2006). Operation of target diagnostics in a petawatt laser environment (invited). Review of Scientific Instruments, 77(10), 10F506. doi:10.1063/1.2217922Bourgade, J. L., Marmoret, R., Darbon, S., Rosch, R., Troussel, P., Villette, B., … Zuber, C. (2008). Diagnostics hardening for harsh environment in Laser Mégajoule (invited). Review of Scientific Instruments, 79(10), 10F301. doi:10.1063/1.2991161Eder, D., Throop, A., Kimbrough, J., Stowell, M., White, D., … Patel, P. (2009). Mitigation of Electromagnetic Pulse (EMP) Effects from Short-Pulse Lasers and Fusion Neutrons. doi:10.2172/950076Kar, S., Ahmed, H., Prasad, R., Cerchez, M., Brauckmann, S., Aurand, B., … Borghesi, M. (2016). Guided post-acceleration of laser-driven ions by a miniature modular structure. Nature Communications, 7(1). doi:10.1038/ncomms10792Mead, M. J., Neely, D., Gauoin, J., Heathcote, R., & Patel, P. (2004). Electromagnetic pulse generation within a petawatt laser target chamber. Review of Scientific Instruments, 75(10), 4225-4227. doi:10.1063/1.1787606Felber, F. S. (2005). Dipole radio-frequency power from laser plasmas with no dipole moment. Applied Physics Letters, 86(23), 231501. doi:10.1063/1.1947911Dubois, J.-L., Lubrano-Lavaderci, F., Raffestin, D., Ribolzi, J., Gazave, J., Fontaine, A. C. L., … Tikhonchuk, V. T. (2014). Target charging in short-pulse-laser–plasma experiments. Physical Review E, 89(1). doi:10.1103/physreve.89.013102Cikhardt, J., Krása, J., De Marco, M., Pfeifer, M., Velyhan, A., Krouský, E., … Kravárik, J. (2014). Measurement of the target current by inductive probe during laser interaction on terawatt laser system PALS. Review of Scientific Instruments, 85(10), 103507. doi:10.1063/1.4898016Poyé, A., Hulin, S., Bailly-Grandvaux, M., Dubois, J.-L., Ribolzi, J., Raffestin, D., … Tikhonchuk, V. (2015). Physics of giant electromagnetic pulse generation in short-pulse laser experiments. Physical Review E, 91(4). doi:10.1103/physreve.91.043106Sprangle, P., Peñano, J. R., Hafizi, B., & Kapetanakos, C. A. (2004). Ultrashort laser pulses and electromagnetic pulse generation in air and on dielectric surfaces. Physical Review E, 69(6). doi:10.1103/physreve.69.066415Poyé, A., Dubois, J.-L., Lubrano-Lavaderci, F., D’Humières, E., Bardon, M., Hulin, S., … Tikhonchuk, V. (2015). Dynamic model of target charging by short laser pulse interactions. Physical Review E, 92(4). doi:10.1103/physreve.92.043107Poyé, A., Hulin, S., Ribolzi, J., Bailly-Grandvaux, M., Lubrano-Lavaderci, F., Bardon, M., … Tikhonchuk, V. (2018). Thin target charging in short laser pulse interactions. Physical Review E, 98(3). doi:10.1103/physreve.98.033201De Marco, M., Pfeifer, M., Krousky, E., Krasa, J., Cikhardt, J., Klir, D., & Nassisi, V. (2014). Basic features of electromagnetic pulse generated in a laser-target chamber at 3-TW laser facility PALS. Journal of Physics: Conference Series, 508, 012007. doi:10.1088/1742-6596/508/1/012007Miragliotta, J. A., Brawley, B., Sailor, C., Spicer, J. B., & Spicer, J. W. M. (2011). Detection of microwave emission from solid targets ablated with an ultrashort pulsed laser. Laser Radar Technology and Applications XVI. doi:10.1117/12.884003Varma, S., Spicer, J., Brawley, B., & Miragliotta, J. (2014). Plasma enhancement of femtosecond laser-induced electromagnetic pulses at metal and dielectric surfaces. Optical Engineering, 53(5), 051515. doi:10.1117/1.oe.53.5.051515Krása, J., De Marco, M., Cikhardt, J., Pfeifer, M., Velyhan, A., Klír, D., … Dudžák, R. (2017). Spectral and temporal characteristics of target current and electromagnetic pulse induced by nanosecond laser ablation. Plasma Physics and Controlled Fusion, 59(6), 065007. doi:10.1088/1361-6587/aa6805De Marco, M., Krása, J., Cikhardt, J., Velyhan, A., Pfeifer, M., Dudžák, R., … Margarone, D. (2017). Electromagnetic pulse (EMP) radiation by laser interaction with a solid H2 ribbon. Physics of Plasmas, 24(8), 083103. doi:10.1063/1.4995475Kugland, N. L., Aurand, B., Brown, C. G., Constantin, C. G., Everson, E. T., Glenzer, S. H., … Niemann, C. (2012). Demonstration of a low electromagnetic pulse laser-driven argon gas jet x-ray source. Applied Physics Letters, 101(2), 024102. doi:10.1063/1.4734506Bradford, P., Woolsey, N. C., Scott, G. G., Liao, G., Liu, H., Zhang, Y., … Neely, D. (2018). EMP control and characterization on high-power laser systems. High Power Laser Science and Engineering, 6. doi:10.1017/hpl.2018.21Lera, R., Bellido, P., Sanchez, I., Mur, P., Seimetz, M., Benlloch, J. M., … Ruiz-de-la-Cruz, A. (2018). Development of a few TW Ti:Sa laser system at 100 Hz for proton acceleration. Applied Physics B, 125(1). doi:10.1007/s00340-018-7113-8Bellido, P., Lera, R., Seimetz, M., Cruz, A. R. la, Torres-Peirò, S., Galán, M., … Benlloch, J. M. (2017). Characterization of protons accelerated from a 3 TW table-top laser system. Journal of Instrumentation, 12(05), T05001-T05001. doi:10.1088/1748-0221/12/05/t05001Seimetz, M., Bellido, P., Soriano, A., Garcia Lopez, J., Jimenez-Ramos, M. C., Fernandez, B., … Benlloch, J. M. (2015). Calibration and Performance Tests of Detectors for Laser-Accelerated Protons. IEEE Transactions on Nuclear Science, 62(6), 3216-3224. doi:10.1109/tns.2015.2480682Consoli, F., De Angelis, R., De Marco, M., Krasa, J., Cikhardt, J., Pfeifer, M., … Dudzak, R. (2018). EMP characterization at PALS on solid-target experiments. Plasma Physics and Controlled Fusion, 60(10), 105006. doi:10.1088/1361-6587/aad709Price, C. J., Donnelly, T. D., Giltrap, S., Stuart, N. H., Parker, S., Patankar, S., … Smith, R. A. (2015). An in-vacuo optical levitation trap for high-intensity laser interaction experiments with isolated microtargets. Review of Scientific Instruments, 86(3), 033502. doi:10.1063/1.4908285Brun, R., & Rademakers, F. (1997). ROOT — An object oriented data analysis framework. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 389(1-2), 81-86. doi:10.1016/s0168-9002(97)00048-