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1. Shock compression experiments using the DiPOLE 100-X laser on the high energy density instrument at the European x-ray free electron laser: Quantitative structural analysis of liquid Sn

Author: Gorman, M, Mcgonegle, D, Smith, R, Singh, S, Jenkins, T, Mcwilliams, R, Albertazzi, B, Ali, S, Antonelli, L, Armstrong, M, Baehtz, C, Ball, O, Banerjee, S, Belonoshko, A, Benuzzi-Mounaix, A, Bolme, C, Bouffetier, V, Briggs, R, Buakor, K, Butcher, T, Di Dio Cafiso, S, Cerantola, V, Chantel, J, Di Cicco, A, Clarke, S, Coleman, A, Collier, J, Collins, G, Comley, A, Coppari, F, Cowan, T, Cristoforetti, G, Cynn, H, Descamps, A, Dorchies, F, Duff, M, Dwivedi, A, Edwards, C, Eggert, J, Errandonea, D, Fiquet, G, Galtier, E, Laso Garcia, A, Ginestet, H, Gizzi, L, Gleason, A, Goede, S, Gonzalez, J, Harmand, M, Hartley, N, Heighway, P, Hernandez-Gomez, C, Higginbotham, A, Höppner, H, Husband, R, Hutchinson, T, Hwang, H, Lazicki, A, Keen, D, Kim, J, Koester, P, Konopkova, Z, Kraus, D, Krygier, A, Labate, L, Lee, Y, Liermann, H, Mason, P, Masruri, M, Massani, B, Mcbride, E, Mcguire, C, Mchardy, J, Merkel, S, Morard, G, Nagler, B, Nakatsutsumi, M, Nguyen-Cong, K, Norton, A, Oleynik, I, Otzen, C, Ozaki, N, Pandolfi, S, Peake, D, Pelka, A, Pereira, K, Phillips, J, Prescher, C, Preston, T, Randolph, L, Ranjan, D, Ravasio, A, Redmer, R, Rips, J, Santamaria-Perez, D, Savage, D, Schoelmerich, M, Schwinkendorf, J, Smith, J, Sollier, A, Spear, J, Spindloe, C, Stevenson, M, Strohm, C, Suer, T, Tang, M, Toncian, M, Toncian, T, Tracy, S, Trapananti, A, Tschentscher, T, Tyldesley, M, Vennari, C, Vinci, T, Vogel, S, Volz, T, Vorberger, J, Walsh, J, Wark, J, Willman, J, Wollenweber, L, Zastrau, U, Brambrink, E, Appel, K, Mcmahon, M, Gorman, M. G., McGonegle, D., Smith, R. F., Singh, S., Jenkins, T., McWilliams, R. S., Albertazzi, B., Ali, S. J., Antonelli, L., Armstrong, M. R., Baehtz, C., Ball, O. B., Banerjee, S., Belonoshko, A. B., Benuzzi-Mounaix, A., Bolme, C. A., Bouffetier, V., Briggs, R., Buakor, K., Butcher, T., Di Dio Cafiso, S., Cerantola, V., Chantel, J., Di Cicco, A., Clarke, S., Coleman, A. L., Collier, J., Collins, G. W., Comley, A. J., Coppari, F., Cowan, T. E., Cristoforetti, G., Cynn, H., Descamps, A., Dorchies, F., Duff, M. J., Dwivedi, A., Edwards, C., Eggert, J. H., Errandonea, D., Fiquet, G., Galtier, E., Laso Garcia, A., Ginestet, H., Gizzi, L., Gleason, A., Goede, S., Gonzalez, J. M., Harmand, M., Hartley, N. J., Heighway, P. G., Hernandez-Gomez, C., Higginbotham, A., Höppner, H., Husband, R. J., Hutchinson, T. M., Hwang, H., Lazicki, A. E., Keen, D. A., Kim, J., Koester, P., Konopkova, Z., Kraus, D., Krygier, A., Labate, L., Lee, Y., Liermann, H. -P., Mason, P., Masruri, M., Massani, B., McBride, E. E., McGuire, C., McHardy, J. D., Merkel, S., Morard, G., Nagler, B., Nakatsutsumi, M., Nguyen-Cong, K., Norton, A. -M., Oleynik, I. I., Otzen, C., Ozaki, N., Pandolfi, S., Peake, D. J., Pelka, A., Pereira, K. A., Phillips, J. P., Prescher, C., Preston, T. R., Randolph, L., Ranjan, D., Ravasio, A., Redmer, R., Rips, J., Santamaria-Perez, D., Savage, D. J., Schoelmerich, M., Schwinkendorf, J. -P., Smith, J., Sollier, A., Spear, J., Spindloe, C., Stevenson, M., Strohm, C., Suer, T. -A., Tang, M., Toncian, M., Toncian, T., Tracy, S. J., Trapananti, A., Tschentscher, T., Tyldesley, M., Vennari, C. E., Vinci, T., Vogel, S. C., Volz, T. J., Vorberger, J., Walsh, J. P. S., Wark, J. S., Willman, J. T., Wollenweber, L., Zastrau, U., Brambrink, E., Appel, K., McMahon, M. I., Gorman, M, Mcgonegle, D, Smith, R, Singh, S, Jenkins, T, Mcwilliams, R, Albertazzi, B, Ali, S, Antonelli, L, Armstrong, M, Baehtz, C, Ball, O, Banerjee, S, Belonoshko, A, Benuzzi-Mounaix, A, Bolme, C, Bouffetier, V, Briggs, R, Buakor, K, Butcher, T, Di Dio Cafiso, S, Cerantola, V, Chantel, J, Di Cicco, A, Clarke, S, Coleman, A, Collier, J, Collins, G, Comley, A, Coppari, F, Cowan, T, Cristoforetti, G, Cynn, H, Descamps, A, Dorchies, F, Duff, M, Dwivedi, A, Edwards, C, Eggert, J, Errandonea, D, Fiquet, G, Galtier, E, Laso Garcia, A, Ginestet, H, Gizzi, L, Gleason, A, Goede, S, Gonzalez, J, Harmand, M, Hartley, N, Heighway, P, Hernandez-Gomez, C, Higginbotham, A, Höppner, H, Husband, R, Hutchinson, T, Hwang, H, Lazicki, A, Keen, D, Kim, J, Koester, P, Konopkova, Z, Kraus, D, Krygier, A, Labate, L, Lee, Y, Liermann, H, Mason, P, Masruri, M, Massani, B, Mcbride, E, Mcguire, C, Mchardy, J, Merkel, S, Morard, G, Nagler, B, Nakatsutsumi, M, Nguyen-Cong, K, Norton, A, Oleynik, I, Otzen, C, Ozaki, N, Pandolfi, S, Peake, D, Pelka, A, Pereira, K, Phillips, J, Prescher, C, Preston, T, Randolph, L, Ranjan, D, Ravasio, A, Redmer, R, Rips, J, Santamaria-Perez, D, Savage, D, Schoelmerich, M, Schwinkendorf, J, Smith, J, Sollier, A, Spear, J, Spindloe, C, Stevenson, M, Strohm, C, Suer, T, Tang, M, Toncian, M, Toncian, T, Tracy, S, Trapananti, A, Tschentscher, T, Tyldesley, M, Vennari, C, Vinci, T, Vogel, S, Volz, T, Vorberger, J, Walsh, J, Wark, J, Willman, J, Wollenweber, L, Zastrau, U, Brambrink, E, Appel, K, Mcmahon, M, Gorman, M. G., McGonegle, D., Smith, R. F., Singh, S., Jenkins, T., McWilliams, R. S., Albertazzi, B., Ali, S. J., Antonelli, L., Armstrong, M. R., Baehtz, C., Ball, O. B., Banerjee, S., Belonoshko, A. B., Benuzzi-Mounaix, A., Bolme, C. A., Bouffetier, V., Briggs, R., Buakor, K., Butcher, T., Di Dio Cafiso, S., Cerantola, V., Chantel, J., Di Cicco, A., Clarke, S., Coleman, A. L., Collier, J., Collins, G. W., Comley, A. J., Coppari, F., Cowan, T. E., Cristoforetti, G., Cynn, H., Descamps, A., Dorchies, F., Duff, M. J., Dwivedi, A., Edwards, C., Eggert, J. H., Errandonea, D., Fiquet, G., Galtier, E., Laso Garcia, A., Ginestet, H., Gizzi, L., Gleason, A., Goede, S., Gonzalez, J. M., Harmand, M., Hartley, N. J., Heighway, P. G., Hernandez-Gomez, C., Higginbotham, A., Höppner, H., Husband, R. J., Hutchinson, T. M., Hwang, H., Lazicki, A. E., Keen, D. A., Kim, J., Koester, P., Konopkova, Z., Kraus, D., Krygier, A., Labate, L., Lee, Y., Liermann, H. -P., Mason, P., Masruri, M., Massani, B., McBride, E. E., McGuire, C., McHardy, J. D., Merkel, S., Morard, G., Nagler, B., Nakatsutsumi, M., Nguyen-Cong, K., Norton, A. -M., Oleynik, I. I., Otzen, C., Ozaki, N., Pandolfi, S., Peake, D. J., Pelka, A., Pereira, K. A., Phillips, J. P., Prescher, C., Preston, T. R., Randolph, L., Ranjan, D., Ravasio, A., Redmer, R., Rips, J., Santamaria-Perez, D., Savage, D. J., Schoelmerich, M., Schwinkendorf, J. -P., Smith, J., Sollier, A., Spear, J., Spindloe, C., Stevenson, M., Strohm, C., Suer, T. -A., Tang, M., Toncian, M., Toncian, T., Tracy, S. J., Trapananti, A., Tschentscher, T., Tyldesley, M., Vennari, C. E., Vinci, T., Vogel, S. C., Volz, T. J., Vorberger, J., Walsh, J. P. S., Wark, J. S., Willman, J. T., Wollenweber, L., Zastrau, U., Brambrink, E., Appel, K., and McMahon, M. I.
Abstract: X-ray free electron laser (XFEL) sources coupled to high-power laser systems offer an avenue to study the structural dynamics of materials at extreme pressures and temperatures. The recent commissioning of the DiPOLE 100-X laser on the high energy density (HED) instrument at the European XFEL represents the state-of-the-art in combining x-ray diffraction with laser compression, allowing for compressed materials to be probed in unprecedented detail. Here, we report quantitative structural measurements of molten Sn compressed to 85(5) GPa and ∼ 3500 K. The capabilities of the HED instrument enable liquid density measurements with an uncertainty of ∼ 1 % at conditions which are extremely challenging to reach via static compression methods. We discuss best practices for conducting liquid diffraction dynamic compression experiments and the necessary intensity corrections which allow for accurate quantitative analysis. We also provide a polyimide ablation pressure vs input laser energy for the DiPOLE 100-X drive laser which will serve future users of the HED instrument.
Published: 2024

2. Visualizing plasmons and ultrafast kinetic instabilities in laser-driven solids using X-ray scattering

Author: (0009-0007-5067-7326) Ordyna, P., Bähtz, C., (0009-0004-2404-9412) Brambrink, E., (0000-0002-8258-3881) Bussmann, M., (0000-0002-7671-0901) Laso García, A., (0000-0001-6994-2475) Garten, M., (0000-0002-6914-4083) Gaus, L., Göde, S., Grenzer, J., (0000-0002-0051-8542) Gutt, C., Höppner, H., (0000-0003-1184-2097) Huang, L., Hübner, U., (0000-0001-6748-0422) Humphries, O. S., (0009-0005-6873-8292) Edward Marré, B., (0000-0002-9556-0662) Metzkes-Ng, J., (0000-0002-9933-3248) Miethlinger, T., (0000-0003-0868-4745) Nakatsutsumi, M., Öztürk, Ö., (0000-0002-3882-510X) Pan, X., (0009-0001-0047-1051) Paschke-Brühl, F.-L., (0009-0001-3308-5376) Pelka, A., (0000-0003-0931-1350) Prencipe, I., (0000-0003-1228-2263) Preston, T. R., (0000-0001-9587-404X) Randolph, L., (0000-0003-4400-1315) Schlenvoigt, H.-P., Schwinkendorf, J.-P., (0000-0002-7162-7500) Šmíd, M., (0000-0001-5007-1868) Starke, S., (0000-0002-4195-2038) Štefaníková, R., Thiessenhusen, E., (0000-0001-7986-3631) Toncian, T., (0000-0003-3926-409X) Zeil, K., (0000-0003-0390-7671) Schramm, U., (0000-0002-5845-000X) Cowan, T., (0000-0003-4861-5584) Kluge, T., (0009-0007-5067-7326) Ordyna, P., Bähtz, C., (0009-0004-2404-9412) Brambrink, E., (0000-0002-8258-3881) Bussmann, M., (0000-0002-7671-0901) Laso García, A., (0000-0001-6994-2475) Garten, M., (0000-0002-6914-4083) Gaus, L., Göde, S., Grenzer, J., (0000-0002-0051-8542) Gutt, C., Höppner, H., (0000-0003-1184-2097) Huang, L., Hübner, U., (0000-0001-6748-0422) Humphries, O. S., (0009-0005-6873-8292) Edward Marré, B., (0000-0002-9556-0662) Metzkes-Ng, J., (0000-0002-9933-3248) Miethlinger, T., (0000-0003-0868-4745) Nakatsutsumi, M., Öztürk, Ö., (0000-0002-3882-510X) Pan, X., (0009-0001-0047-1051) Paschke-Brühl, F.-L., (0009-0001-3308-5376) Pelka, A., (0000-0003-0931-1350) Prencipe, I., (0000-0003-1228-2263) Preston, T. R., (0000-0001-9587-404X) Randolph, L., (0000-0003-4400-1315) Schlenvoigt, H.-P., Schwinkendorf, J.-P., (0000-0002-7162-7500) Šmíd, M., (0000-0001-5007-1868) Starke, S., (0000-0002-4195-2038) Štefaníková, R., Thiessenhusen, E., (0000-0001-7986-3631) Toncian, T., (0000-0003-3926-409X) Zeil, K., (0000-0003-0390-7671) Schramm, U., (0000-0002-5845-000X) Cowan, T., and (0000-0003-4861-5584) Kluge, T.
Abstract: Ultra-intense lasers that ionize atoms and accelerate electrons in solids to near the speed of light can lead to kinetic instabilities that alter the laser absorption and subsequent electron transport, isochoric heating, and ion acceleration. These instabilities can be difficult to characterize, but X-ray scattering at keV photon energies allows for their visualization with femtosecond temporal resolution on the few nanometer mesoscale. Here, we perform such experiment on laser-driven flat silicon membranes that shows the development of structure with a dominant scale of 60 nm in the plane of the laser axis and laser polarization, and 95 nm in the vertical direction with a growth rate faster than 0.1 fs−1 . Combining the XFEL experiments with simulations provides a complete picture of the structural evolution of ultra-fast laser-induced plasma density development, indicating the excita- tion of plasmons and a filamentation instability. Particle-in-cell simulations confirm that these signals are due to an oblique two-stream filamentation instability. These findings provide new insight into ultra-fast instability and heating processes in solids under extreme conditions at the nanometer level with possible implications for laser particle acceleration, inertial confinement fusion, and laboratory astrophysics.
Published: 2024

3. Visualizing Ultrafast Kinetic Instabilities in Laser-Driven Solids using X-ray Scattering

Author: Ordyna, P., (0000-0002-8258-3881) Bussmann, M., (0000-0002-6914-4083) Gaus, L., Grenzer, J., Gutt, C., (0000-0003-1184-2097) Huang, L., (0000-0002-7671-0901) Laso García, A., (0000-0001-6994-2475) Garten, M., Höppner, H., Humpries, O., (0009-0005-6873-8292) Marre, B. E., (0000-0002-9556-0662) Metzkes-Ng, J., Nakatsutsumi, M., Öztürk, Ö., (0000-0002-3882-510X) Pan, X., (0009-0001-0047-1051) Paschke-Brühl, F.-L., Pelka, A., (0000-0003-0931-1350) Prencipe, I., Randolph, L., (0000-0003-4400-1315) Schlenvoigt, H.-P., (0000-0002-7162-7500) Smid, M., (0000-0002-4195-2038) Stefanikova, R., Thiessenhusen, E., (0000-0001-7986-3631) Toncian, T., (0000-0003-3926-409X) Zeil, K., (0000-0003-0390-7671) Schramm, U., (0000-0002-5845-000X) Cowan, T., (0000-0003-4861-5584) Kluge, T., Ordyna, P., (0000-0002-8258-3881) Bussmann, M., (0000-0002-6914-4083) Gaus, L., Grenzer, J., Gutt, C., (0000-0003-1184-2097) Huang, L., (0000-0002-7671-0901) Laso García, A., (0000-0001-6994-2475) Garten, M., Höppner, H., Humpries, O., (0009-0005-6873-8292) Marre, B. E., (0000-0002-9556-0662) Metzkes-Ng, J., Nakatsutsumi, M., Öztürk, Ö., (0000-0002-3882-510X) Pan, X., (0009-0001-0047-1051) Paschke-Brühl, F.-L., Pelka, A., (0000-0003-0931-1350) Prencipe, I., Randolph, L., (0000-0003-4400-1315) Schlenvoigt, H.-P., (0000-0002-7162-7500) Smid, M., (0000-0002-4195-2038) Stefanikova, R., Thiessenhusen, E., (0000-0001-7986-3631) Toncian, T., (0000-0003-3926-409X) Zeil, K., (0000-0003-0390-7671) Schramm, U., (0000-0002-5845-000X) Cowan, T., and (0000-0003-4861-5584) Kluge, T.
Abstract: Ultra-intense lasers that ionize and accelerate electrons in solids to near the speed of light can lead to kinetic instabilities that alter the laser absorption and subsequent electron transport, isochoric heating, and ion acceleration. These instabilities can be difficult to characterize, but a novel approach using X-ray scattering at keV energies allows for their visualization with femtosecond temporal resolution on the few nanometer mesoscale. Our experiments on laser-driven flat silicon membranes show the development of structure with a dominant scale of $~60\unit{nm}$ in the plane of the laser axis and laser polarization, and $~95\unit{nm}$ in the vertical direction with a growth rate faster than $0.1/\mathrm{fs}$. Combining the XFEL experiments with simulations provides a complete picture of the structural evolution of ultra-fast laser-induced instability development, indicating the excitation of surface plasmons and the growth of a new type of filamentation instability. These findings provide new insight into the ultra-fast instability processes in solids under extreme conditions at the nanometer level with important implications for inertial confinement fusion and laboratory astrophysics.
Published: 2023

4. Commissioning and First User Experiments with ReLaX and XFEL Beam

Author: (0000-0002-7671-0901) Laso García, A., Arefiev, A., Kemp, A., Allen, C. H., Bähtz, C., Nagler, B., Palmer, C. A. J., Murphy, C. D., Spindloe, C., Brown, C. R. D., Neely, D., (0000-0002-6350-4180) Kraus, D., Marley, E., Hartouni, E. P., Fiuza, F., Grim, G. P., Cochran, G. E., (0000-0003-4400-1315) Schlenvoigt, H.-P., (0000-0003-0931-1350) Prencipe, I., Williams, J., Green, J., Eggert, J. H., (0000-0003-3926-409X) Zeil, K., Lancaster, K. L., Divol, L., (0000-0002-6914-4083) Gaus, L., (0000-0003-1184-2097) Huang, L., Schoelmerich, M., (0000-0001-6200-6406) Rehwald, M., Oliver, M., Rödel, M., Macdonald, M., (0000-0002-7162-7500) Smid, M., Makita, M., Nakatsutsumi, M., (0000-0001-6748-0422) Humphries, O. S., Neumayer, P. B., Mabey, P., Shepherd, R. L., Gray, R., Wilks, S. C., Le Pape, S., Kerr, S. M., Glenzer, S. H., Funk, S., Gales, S. G., (0000-0002-5845-000X) Cowan, T., White, T. G., (0000-0003-4861-5584) Kluge, T., Doeppner, T., (0000-0001-7986-3631) Toncian, T., Zastrau, U., (0000-0003-0390-7671) Schramm, U., Ping, Y., He, Z., Höppner, H., Pelka, A., (0000-0002-7671-0901) Laso García, A., Arefiev, A., Kemp, A., Allen, C. H., Bähtz, C., Nagler, B., Palmer, C. A. J., Murphy, C. D., Spindloe, C., Brown, C. R. D., Neely, D., (0000-0002-6350-4180) Kraus, D., Marley, E., Hartouni, E. P., Fiuza, F., Grim, G. P., Cochran, G. E., (0000-0003-4400-1315) Schlenvoigt, H.-P., (0000-0003-0931-1350) Prencipe, I., Williams, J., Green, J., Eggert, J. H., (0000-0003-3926-409X) Zeil, K., Lancaster, K. L., Divol, L., (0000-0002-6914-4083) Gaus, L., (0000-0003-1184-2097) Huang, L., Schoelmerich, M., (0000-0001-6200-6406) Rehwald, M., Oliver, M., Rödel, M., Macdonald, M., (0000-0002-7162-7500) Smid, M., Makita, M., Nakatsutsumi, M., (0000-0001-6748-0422) Humphries, O. S., Neumayer, P. B., Mabey, P., Shepherd, R. L., Gray, R., Wilks, S. C., Le Pape, S., Kerr, S. M., Glenzer, S. H., Funk, S., Gales, S. G., (0000-0002-5845-000X) Cowan, T., White, T. G., (0000-0003-4861-5584) Kluge, T., Doeppner, T., (0000-0001-7986-3631) Toncian, T., Zastrau, U., (0000-0003-0390-7671) Schramm, U., Ping, Y., He, Z., Höppner, H., and Pelka, A.
Abstract: In this presentation we provide an overview of the commissioning and first user experiment of ReLaX in combination with the XFEL beam. We will introduce the setup and laser parameters. We will show the established standard setup combining small-angle x-ray scattering (SAXS), phase-contrast imaging (PCI) and spectroscopy techniques. Finally we will show examples of the data obtained in the interaction of the ReLaX laser with targets of interested for the short-pulse laser community.
Published: 2022

5. Combined Phase Contrast Imaging and Small-Angle X-Ray Scattering Diagnostic of Relativistic Plasmas at the High Energy Density Instrument at European XFEL

Author: (0000-0002-7671-0901) Laso García, A., Arefiev, A., Kemp, A., Allen, C. H., Bähtz, C., Nagler, B., Palmer, C. A. J., Murphy, C. D., Spindloe, C., Brown, C. R. D., Neely, D., (0000-0002-6350-4180) Kraus, D., Marley, E., Hartouni, E. P., Fiuza, F., Grim, G. P., Cochran, G. E., (0000-0003-4400-1315) Schlenvoigt, H.-P., (0000-0003-0931-1350) Prencipe, I., Williams, J., Green, J., Eggert, J. H., (0000-0003-3926-409X) Zeil, K., Lancaster, K. L., Divol, L., (0000-0002-6914-4083) Gaus, L., (0000-0003-1184-2097) Huang, L., Schoelmerich, M., (0000-0001-6200-6406) Rehwald, M., Oliver, M., Rödel, M., Macdonald, M., (0000-0002-7162-7500) Smid, M., Makita, M., Nakatsutsumi, M., (0000-0001-6748-0422) Humphries, O. S., Neumayer, P. B., Mabey, P., Shepherd, R. L., Gray, R., Wilks, S. C., Le Pape, S., Kerr, S. M., Glenzer, S. H., Funk, S., Gales, S. G., (0000-0002-5845-000X) Cowan, T., White, T. G., (0000-0003-4861-5584) Kluge, T., Doeppner, T., (0000-0001-7986-3631) Toncian, T., Zastrau, U., (0000-0003-0390-7671) Schramm, U., Ping, Y., He, Z., Höppner, H., Pelka, A., (0000-0002-7671-0901) Laso García, A., Arefiev, A., Kemp, A., Allen, C. H., Bähtz, C., Nagler, B., Palmer, C. A. J., Murphy, C. D., Spindloe, C., Brown, C. R. D., Neely, D., (0000-0002-6350-4180) Kraus, D., Marley, E., Hartouni, E. P., Fiuza, F., Grim, G. P., Cochran, G. E., (0000-0003-4400-1315) Schlenvoigt, H.-P., (0000-0003-0931-1350) Prencipe, I., Williams, J., Green, J., Eggert, J. H., (0000-0003-3926-409X) Zeil, K., Lancaster, K. L., Divol, L., (0000-0002-6914-4083) Gaus, L., (0000-0003-1184-2097) Huang, L., Schoelmerich, M., (0000-0001-6200-6406) Rehwald, M., Oliver, M., Rödel, M., Macdonald, M., (0000-0002-7162-7500) Smid, M., Makita, M., Nakatsutsumi, M., (0000-0001-6748-0422) Humphries, O. S., Neumayer, P. B., Mabey, P., Shepherd, R. L., Gray, R., Wilks, S. C., Le Pape, S., Kerr, S. M., Glenzer, S. H., Funk, S., Gales, S. G., (0000-0002-5845-000X) Cowan, T., White, T. G., (0000-0003-4861-5584) Kluge, T., Doeppner, T., (0000-0001-7986-3631) Toncian, T., Zastrau, U., (0000-0003-0390-7671) Schramm, U., Ping, Y., He, Z., Höppner, H., and Pelka, A.
Abstract: The High Energy Density (HED) instrument at the European XFEL provides a platform to study hot and warm dense matter. The Helmholtz International Beamline for Extreme Fields (HiBEF) is a User Consortium supplying HED with two laser systems (the high-intensity ReLaX laser, by Amplitude Technologies, and the high-energy Dipole-100X laser, by STFC), Diamond Anvil Cells setup and high-pulsed magnetic fields. These tools in combination with the XFEL beam enable the investigation of relativistic laser plasmas, strong-field QED phenomena, high-pressure astro- and planetary physics as well as magnetic phenomena in condensed matter. The successful commissioning of the ultra-short pulse high-intensity ReLaX laser, provides new unique opportunities in the plasma and high-field physics fields [1]. ReLaX is a double CPA Ti:Sa laser capable of delivering up to 300 TW pulses on target. In the first commissioning phase, 100 TW pulses were used, reaching intensities up to 1020 W/cm2. Small-Angle X-Ray Scattering (SAXS) without the need of a beamstop was first commissioned at HED in September 2019. Two highly annealed pyrolytic graphite (HAPG) crystals were used to reflect the SAXS photons onto a detector while allowing the main XFEL beam to go through [2]. In April and May 2021, Small Angle X-Ray Scattering and Phase Contrast Imaging (PCI) were simultaneously demonstrated in pump-probe experiments at HED in a community experiment involving 15 institutions from all over the world. In this talk we will present the preliminary results of this community experiment probing ultrafast phenomena in a wide array of target configurations: hole boring in wires, shockwave generation in CH blocks, buried heating of a wire inside a CH medium, foam ionization and collective effects in heated foils. [1] A. Laso Garcia, H. Hoeppner, A. Pelka et al., “ReLaX: the HiBEF high-intensity short-pulse laser driver for relativistic laser-matter interaction and strong-field science at the HED instrument at Eu
Published: 2022

6. The High Energy Density Scientific Instrument at the European XFEL

Author: Zastrau, U., Appel, K., Bähtz, C., Bähr, O., Batchelor, L., Berghäuser, A., Banjafar, M., Brambrink, E., Cerantola, V., (0000-0002-5845-000X) Cowan, T., Damker, H., Dittrich, S., Di Dio Cafiso, S. D., Dreyer, J., Engel, H.-O., Feldmann, T., Findeisen, S., Foese, M., Fulla-Marsa, D., Göde, S., Hassan, M. K. Y., Hauser, J., (0000-0001-6706-4541) Herrmannsdörfer, T., Höppner, H., Kaa, J., Kaever, P., Knöfel, K., Konopkova, Z., (0000-0002-7671-0901) Laso García, A., Liermann, H.-P., Mainberger, J., Makita, M., Martens, E.-C., McBride, E. E., Möller, D., Nakatsutsumi, M., Pelka, A., Plueckthun, C., Prescher, C., Preston, T. R., Röper, M., Schmidt, A., Seidel, W., Schwinkendorf, J.-P., Schoelmerich, M. O., (0000-0003-0390-7671) Schramm, U., Schropp, A., Strohm, C., Sukharnikov, K., Talkovski, P., Thorpe, I., Toncian, M., (0000-0001-7986-3631) Toncian, T., Wollenweber, L., (0000-0001-5819-2867) Yamamoto, S., Tschentscher, T., Zastrau, U., Appel, K., Bähtz, C., Bähr, O., Batchelor, L., Berghäuser, A., Banjafar, M., Brambrink, E., Cerantola, V., (0000-0002-5845-000X) Cowan, T., Damker, H., Dittrich, S., Di Dio Cafiso, S. D., Dreyer, J., Engel, H.-O., Feldmann, T., Findeisen, S., Foese, M., Fulla-Marsa, D., Göde, S., Hassan, M. K. Y., Hauser, J., (0000-0001-6706-4541) Herrmannsdörfer, T., Höppner, H., Kaa, J., Kaever, P., Knöfel, K., Konopkova, Z., (0000-0002-7671-0901) Laso García, A., Liermann, H.-P., Mainberger, J., Makita, M., Martens, E.-C., McBride, E. E., Möller, D., Nakatsutsumi, M., Pelka, A., Plueckthun, C., Prescher, C., Preston, T. R., Röper, M., Schmidt, A., Seidel, W., Schwinkendorf, J.-P., Schoelmerich, M. O., (0000-0003-0390-7671) Schramm, U., Schropp, A., Strohm, C., Sukharnikov, K., Talkovski, P., Thorpe, I., Toncian, M., (0000-0001-7986-3631) Toncian, T., Wollenweber, L., (0000-0001-5819-2867) Yamamoto, S., and Tschentscher, T.
Abstract: The European XFEL delivers up to 27000 intense (>1012 photons) pulses per second, of ultrashort (≤50 fs) and transversely coherent X-ray radiation, at a maximum repetition rate of 4.5 MHz. Its unique X-ray beam parameters enable groundbreaking experiments in matter at extreme conditions at the High Energy Density (HED) scientific instrument. The performance of the HED instrument during its first two years of operation, its scientific remit, as well as ongoing installations towards full operation are presented. Scientific goals of HED include the investigation of extreme states of matter created by intense laser pulses, diamond anvil cells, or pulsed magnets, and ultrafast X-ray methods that allow their diagnosis using self-amplified spontaneous emission between 5 and 25 keV, coupled with X-ray monochromators and optional seeded beam operation. The HED instrument provides two target chambers, X-ray spectrometers for emission and scattering, X-ray detectors, and a timing tool to correct for residual timing jitter between laser and X-ray pulses.
Published: 2021

7. ReLaX: the Helmholtz International Beamline for Extreme Fields high-intensity short-pulse laser driver for relativistic laser–matter interaction and strong-field science using the high energy density instrument at the European X-ray free electron laser facility

Author: (0000-0002-7671-0901) Laso García, A., Höppner, H., Pelka, A., Bähtz, C., Brambrink, E., Di Dio Cafiso, S. D., Dreyer, J., Göde, S., Hassan, M. K. Y., (0000-0003-4861-5584) Kluge, T., Liu, J., Makita, M., Möller, D., (0000-0003-0868-4745) Nakatsutsumi, M., (0000-0003-1228-2263) Preston, T. R., Priebe, G., (0000-0003-4400-1315) Schlenvoigt, H.-P., Schwinkendorf, J.-P., (0000-0002-7162-7500) Smid, M., Talposi, A.-M., Toncian, M., (0000-0002-3575-4449) Zastrau, U., (0000-0003-0390-7671) Schramm, U., (0000-0002-5845-000X) Cowan, T., (0000-0001-7986-3631) Toncian, T., (0000-0002-7671-0901) Laso García, A., Höppner, H., Pelka, A., Bähtz, C., Brambrink, E., Di Dio Cafiso, S. D., Dreyer, J., Göde, S., Hassan, M. K. Y., (0000-0003-4861-5584) Kluge, T., Liu, J., Makita, M., Möller, D., (0000-0003-0868-4745) Nakatsutsumi, M., (0000-0003-1228-2263) Preston, T. R., Priebe, G., (0000-0003-4400-1315) Schlenvoigt, H.-P., Schwinkendorf, J.-P., (0000-0002-7162-7500) Smid, M., Talposi, A.-M., Toncian, M., (0000-0002-3575-4449) Zastrau, U., (0000-0003-0390-7671) Schramm, U., (0000-0002-5845-000X) Cowan, T., and (0000-0001-7986-3631) Toncian, T.
Abstract: High-energy and high-intensity lasers are essential for pushing the boundaries of science. Their development has allowed leaps forward in basic research areas, including laser–plasma interaction, high-energy density science, metrology, biology and medical technology. The Helmholtz International Beamline for Extreme Fields user consortium contributes and operates two high-peak-power optical lasers using the high energy density instrument at the European X-ray free electron laser (EuXFEL) facility. These lasers will be used to generate transient extreme states of density and temperature to be probed by the X-ray beam. This paper introduces the ReLaX laser, a short-pulse high-intensity Ti:Sa laser system, and discusses its characteristics as available for user experiments. It will also present the first experimental commissioning results validating its successful integration into the EuXFEL infrastructure and viability as a relativistic-intensity laser driver.
Published: 2021

8. The High Energy Density Scientific Instrument at the European XFEL

Author: Zastrau, U, Appel, K, Baehtz, C, Baehr, O, Batchelor, L, Berghäuser, A, Banjafar, M, Brambrink, E, Cerantola, V, Cowan, T, Damker, H, Dietrich, S, Di Dio Cafiso, S, Dreyer, J, Engel, H, Feldmann, T, Findeisen, S, Foese, M, Fulla-Marsa, D, Göde, S, Hassan, M, Hauser, J, Herrmannsdörfer, T, Höppner, H, Kaa, J, Kaever, P, Knöfel, K, Konôpková, Z, Laso García, A, Liermann, H, Mainberger, J, Makita, M, Martens, E, Mcbride, E, Möller, D, Nakatsutsumi, M, Pelka, A, Plueckthun, C, Prescher, C, Preston, T, Röper, M, Schmidt, A, Seidel, W, Schwinkendorf, J, Schoelmerich, M, Schramm, U, Schropp, A, Strohm, C, Sukharnikov, K, Talkovski, P, Thorpe, I, Toncian, M, Toncian, T, Wollenweber, L, Yamamoto, S, Tschentscher, T, Zastrau, Ulf, Appel, Karen, Baehtz, Carsten, Baehr, Oliver, Batchelor, Lewis, Berghäuser, Andreas, Banjafar, Mohammadreza, Brambrink, Erik, Cerantola, Valerio, Cowan, Thomas E, Damker, Horst, Dietrich, Steffen, Di Dio Cafiso, Samuele, Dreyer, Jörn, Engel, Hans Olaf, Feldmann, Thomas, Findeisen, Stefan, Foese, Manon, Fulla-Marsa, Daniel, Göde, Sebastian, Hassan, Mohammed, Hauser, Jens, Herrmannsdörfer, Thomas, Höppner, Hauke, Kaa, Johannes, Kaever, Peter, Knöfel, Klaus, Konôpková, Zuzana, Laso García, Alejandro, Liermann, Hanns Peter, Mainberger, Jona, Makita, Mikako, Martens, Eike Christian, McBride, Emma E, Möller, Dominik, Nakatsutsumi, Motoaki, Pelka, Alexander, Plueckthun, Christian, Prescher, Clemens, Preston, Thomas R, Röper, Michael, Schmidt, Andreas, Seidel, Wolfgang, Schwinkendorf, Jan Patrick, Schoelmerich, Markus O, Schramm, Ulrich, Schropp, Andreas, Strohm, Cornelius, Sukharnikov, Konstantin, Talkovski, Peter, Thorpe, Ian, Toncian, Monika, Toncian, Toma, Wollenweber, Lennart, Yamamoto, Shingo, Tschentscher, Thomas, Zastrau, U, Appel, K, Baehtz, C, Baehr, O, Batchelor, L, Berghäuser, A, Banjafar, M, Brambrink, E, Cerantola, V, Cowan, T, Damker, H, Dietrich, S, Di Dio Cafiso, S, Dreyer, J, Engel, H, Feldmann, T, Findeisen, S, Foese, M, Fulla-Marsa, D, Göde, S, Hassan, M, Hauser, J, Herrmannsdörfer, T, Höppner, H, Kaa, J, Kaever, P, Knöfel, K, Konôpková, Z, Laso García, A, Liermann, H, Mainberger, J, Makita, M, Martens, E, Mcbride, E, Möller, D, Nakatsutsumi, M, Pelka, A, Plueckthun, C, Prescher, C, Preston, T, Röper, M, Schmidt, A, Seidel, W, Schwinkendorf, J, Schoelmerich, M, Schramm, U, Schropp, A, Strohm, C, Sukharnikov, K, Talkovski, P, Thorpe, I, Toncian, M, Toncian, T, Wollenweber, L, Yamamoto, S, Tschentscher, T, Zastrau, Ulf, Appel, Karen, Baehtz, Carsten, Baehr, Oliver, Batchelor, Lewis, Berghäuser, Andreas, Banjafar, Mohammadreza, Brambrink, Erik, Cerantola, Valerio, Cowan, Thomas E, Damker, Horst, Dietrich, Steffen, Di Dio Cafiso, Samuele, Dreyer, Jörn, Engel, Hans Olaf, Feldmann, Thomas, Findeisen, Stefan, Foese, Manon, Fulla-Marsa, Daniel, Göde, Sebastian, Hassan, Mohammed, Hauser, Jens, Herrmannsdörfer, Thomas, Höppner, Hauke, Kaa, Johannes, Kaever, Peter, Knöfel, Klaus, Konôpková, Zuzana, Laso García, Alejandro, Liermann, Hanns Peter, Mainberger, Jona, Makita, Mikako, Martens, Eike Christian, McBride, Emma E, Möller, Dominik, Nakatsutsumi, Motoaki, Pelka, Alexander, Plueckthun, Christian, Prescher, Clemens, Preston, Thomas R, Röper, Michael, Schmidt, Andreas, Seidel, Wolfgang, Schwinkendorf, Jan Patrick, Schoelmerich, Markus O, Schramm, Ulrich, Schropp, Andreas, Strohm, Cornelius, Sukharnikov, Konstantin, Talkovski, Peter, Thorpe, Ian, Toncian, Monika, Toncian, Toma, Wollenweber, Lennart, Yamamoto, Shingo, and Tschentscher, Thomas
Abstract: The European XFEL delivers up to 27000 intense (>1012photons) pulses per second, of ultrashort (≤50 fs) and transversely coherent X-ray radiation, at a maximum repetition rate of 4.5MHz. Its unique X-ray beam parameters enable groundbreaking experiments in matter at extreme conditions at the High Energy Density (HED) scientific instrument. The performance of the HED instrument during its first two years of operation, its scientific remit, as well as ongoing installations towards full operation are presented. Scientific goals of HED include the investigation of extreme states of matter created by intense laser pulses, diamond anvil cells, or pulsed magnets, and ultrafast X-ray methods that allow their diagnosis using self-amplified spontaneous emission between 5 and 25keV, coupled with X-ray monochromators and optional seeded beam operation. The HED instrument provides two target chambers, X-ray spectrometers for emission and scattering, X-ray detectors, and a timing tool to correct for residual timing jitter between laser and X-ray pulses.
Published: 2021

9. ReLaX: the Helmholtz International Beamline for Extreme Fields high-intensity short-pulse laser driver for relativistic laser–matter interaction and strong-field science using the high energy density instrument at the European X-ray free electron laser facility

Author: Laso Garcia, A., primary, Höppner, H., additional, Pelka, A., additional, Bähtz, C., additional, Brambrink, E., additional, Di Dio Cafiso, S., additional, Dreyer, J., additional, Göde, S., additional, Hassan, M., additional, Kluge, T., additional, Liu, J., additional, Makita, M., additional, Möller, D., additional, Nakatsutsumi, M., additional, Preston, T. R., additional, Priebe, G., additional, Schlenvoigt, H.-P., additional, Schwinkendorf, J.-P., additional, Šmíd, M., additional, Talposi, A.-M., additional, Toncian, M., additional, Zastrau, U., additional, Schramm, U., additional, Cowan, T. E., additional, and Toncian, T., additional
Published: 2021
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10. Photodissociation of aligned CH3I and C6H3F2I molecules probed with time-resolved Coulomb explosion imaging by site-selective extreme ultraviolet ionization

Author: Amini, K, Savelyev, E, Brauße, F, Berrah, N, Bomme, C, Brouard, M, Burt, M, Christensen, L, Düsterer, S, Erk, B, Höppner, H, Kierspel, T, Krecinic, F, Lauer, A, Lee, JWL, Müller, M, Müller, E, Mullins, T, Redlin, H, Schirmel, N, Thøgersen, J, Techert, S, Toleikis, S, Treusch, R, Trippel, S, Ulmer, A, Vallance, C, Wiese, J, Johnsson, P, Küpper, J, Rudenko, A, Rouzée, A, Stapelfeldt, H, Rolles, D, and Boll, R
Subjects: ARTICLES, Physics::Atomic and Molecular Clusters, lcsh:QD901-999, lcsh:Crystallography, Physics::Chemical Physics, Experimental Methodologies
Abstract: We explore time-resolved Coulomb explosion induced by intense, extreme ultraviolet (XUV) femtosecond pulses from a free-electron laser as a method to image photo-induced molecular dynamics in two molecules, iodomethane and 2,6-difluoroiodobenzene. At an excitation wavelength of 267 nm, the dominant reaction pathway in both molecules is neutral dissociation via cleavage of the carbon–iodine bond. This allows investigating the influence of the molecular environment on the absorption of an intense, femtosecond XUV pulse and the subsequent Coulomb explosion process. We find that the XUV probe pulse induces local inner-shell ionization of atomic iodine in dissociating iodomethane, in contrast to non-selective ionization of all photofragments in difluoroiodobenzene. The results reveal evidence of electron transfer from methyl and phenyl moieties to a multiply charged iodine ion. In addition, indications for ultrafast charge rearrangement on the phenyl radical are found, suggesting that time-resolved Coulomb explosion imaging is sensitive to the localization of charge in extended molecules.
Published: 2018
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11. Exploring the multiparameter nature of EUV-visible wave mixing at the FERMI FEL

Author: Foglia, L., primary, Capotondi, F., additional, Höppner, H., additional, Gessini, A., additional, Giannessi, L., additional, Kurdi, G., additional, Lopez Quintas, I., additional, Masciovecchio, C., additional, Kiskinova, M., additional, Mincigrucci, R., additional, Naumenko, D., additional, Nikolov, I. P., additional, Pedersoli, E., additional, Rossi, G. M., additional, Simoncig, A., additional, and Bencivenga, F., additional
Published: 2019
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12. Exploring the multiparameter nature of EUV-visible wave mixing at the FERMI FEL

Author: Foglia, L., Capotondi, F., Höppner, H., Gessini, A., Giannessi, L., Kurdi, G., Lopez Quintas, I., Masciovecchio, C., Kiskinova, M., Mincigrucci, R., Naumenko, D., Nikolov, I. P., Pedersoli, E., Rossi, G. M., Simoncig, A., Bencivenga, F., Foglia, L., Capotondi, F., Höppner, H., Gessini, A., Giannessi, L., Kurdi, G., Lopez Quintas, I., Masciovecchio, C., Kiskinova, M., Mincigrucci, R., Naumenko, D., Nikolov, I. P., Pedersoli, E., Rossi, G. M., Simoncig, A., and Bencivenga, F.
Abstract: The rapid development of extreme ultraviolet (EUV) and x-ray ultrafast coherent light sources such as free electron lasers (FELs) has triggered the extension of wave-mixing techniques to short wavelengths. This class of experiments, based on the interaction of matter with multiple light pulses through the Nth order susceptibility, holds the promise of combining intrinsic ultrafast time resolution and background-free signal detection with nanometer spatial resolution and chemical specificity. A successful approach in this direction has been the combination of the unique characteristics of the seeded FEL FERMI with dedicated four-wave-mixing (FWM) setups, which leads to the demonstration of EUV-based transient grating (TG) spectroscopy. In this perspective paper, we discuss how the TG approach can be extended toward more general FWM spectroscopies by exploring the intrinsic multiparameter nature of nonlinear processes, which derives from the ability of controlling the properties of each field independently.
Published: 2019

13. Initial observations of the femtosecond timing jitter at the European XFEL

Author: Kirkwood, H. J., Letrun, R., Tanikawa, T., Liu, J., Nakatsutsumi, M., Emons, M., Jezynski, T., Palmer, G., Lederer, M., Bean, R., Buck, J., Di Dio Cafiso, S. D., Graceffa, R., Grünert, J., Göde, S., Höppner, H., Kim, Y., Konopkova, Z., Mills, G., Makita, M., Pelka, A., Preston, T. R., Sikorski, M., Takem, C. M. S., Giewekemeyer, K., Chollet, M., Vagovic, P., Chapman, H. N., Mancuso, A. P., Sato, T., Kirkwood, H. J., Letrun, R., Tanikawa, T., Liu, J., Nakatsutsumi, M., Emons, M., Jezynski, T., Palmer, G., Lederer, M., Bean, R., Buck, J., Di Dio Cafiso, S. D., Graceffa, R., Grünert, J., Göde, S., Höppner, H., Kim, Y., Konopkova, Z., Mills, G., Makita, M., Pelka, A., Preston, T. R., Sikorski, M., Takem, C. M. S., Giewekemeyer, K., Chollet, M., Vagovic, P., Chapman, H. N., Mancuso, A. P., and Sato, T.
Abstract: Intense, ultrashort, and high-repetition-rate X-ray pulses, combined with a femtosecond optical laser, allow pump-probe experiments with fast data acquisition and femtosecond time resolution. However, the relative timing of the X-ray pulses and the optical laser pulses can be controlled only to a level of the intrinsic error of the instrument which, without characterization, limits the time resolution of experiments. This limitation inevitably calls for a precise determination of the relative arrival time, which can be used after measurement for sorting and tagging the experimental data to a much finer resolution than it can be controlled to. The observed root-mean-square timing jitter between the X-ray and the optical laser at the SPB/SFX instrument at European XFEL was 308\&\#x00A0;fs. This first measurement of timing jitter at the European XFEL provides an important step in realizing ultrafast experiments at this novel X-ray source. A method for determining the change in the complex refractive index of samples is also presented.
Published: 2019

14. TO THE EDITOR

Author: Hoppner, H. Nicoll
Published: 1971

15. Simultaneous Operation of Two Soft X-Ray Free-Electron Lasers Driven by One Linear Accelerator

Author: Faatz, B., Plönjes, E., Bican, Y., Meissner, D., Mildner, N., Miltchev, V., Molnar, S., Mross, D., Müller, F., Neumann, R., Neumann, P., Nölle, D., Obier, F., Bilani, O., Pelzer, M., Peters, H-B, Petersen, K., Petrosyan, A., Petrosyan, G., Petrosyan, L., Petrosyan, Vahan, Petrov, A., Pfeiffer, S., Piotrowski, A., Bödewadt, J., Pisarov, Z., Plath, T., Pototzki, P., Prandolini, M. J., Prenting, J., Priebe, G., Racky, B., Ramm, T., Rehlich, K., Riedel, R., Böhnert, M., Roggli, M., Röhling, M., Rönsch-Schulenburg, J., Rossbach, J., Rybnikov, V., Schaefer, Juergen, Schaffran, J., Schlarb, H., Schlesselmann, G., Schlösser, M., Böspflug, R., Schmid, P., Schmidt, C., Schmidt-Föhre, F., Schmitz, Michael, Schneidmiller, E., Schöps, A., Scholz, Matthias, Schreiber, Siegfried, Schuett, Katrin, Schütz, U., Bonfigt, S., Schulte-Schrepping, H., Schulz, M., Shabunov, A., Smirnov, P., Sombrowski, E., Sorokin, Andrey, Sparr, B., Spengler, J., Staack, M., Stadler, M., Bolz, H., Stechmann, C., Steffen, Boris, Stojanovic, N., Sychev, V., Syresin, E., Tanikawa, T., Tavella, F., Tesch, N., Tiedtke, K., Tischer, M., Borges, F., Treusch, R., Tripathi, S., Vagin, P., Vetrov, P., Vilcins, S., Vogt, Mathias, Wagner, A de Zubiaurre, Wamsat, T., Weddig, H., Weichert, G., Borkenhagen, O., Weigelt, H., Wentowski, N., Wiebers, Christian, Wilksen, T., Willner, A., Wittenburg, Katrin, Wohlenberg, T., Wortmann, J., Wurth, W., Yurkov, M., Brachmanski, Maciej, Zagorodnov, I., Zemella, J., Ackermann, S., Braune, M., Brinkmann, A., Brovko, Oleg, Bruns, T., Castro, P., Chen, J., Czwalinna, M. K., Damker, Horst-Guenter, Decking, W., Degenhardt, M., Agababyan, A., Delfs, A., Delfs, T., Deng, H., Dressel, M., Duhme, H-T, Düsterer, S., Eckoldt, H., Eislage, A., Felber, M., Feldhaus, J., Asgekar, V., Gessler, P., Gibau, M., Golubeva, N., Golz, T., Gonschior, J., Grebentsov, A., Grecki, M., Grün, C., Grunewald, S., Hacker, K., Ayvazyan, V., Hänisch, L., Hage, A., Hans, T., Hass, E., Hauberg, A., Hensler, O., Hesse, M., Heuck, K., Hidvegi, A., Holz, M., Baark, S., Honkavaara, K., Höppner, H., Ignatenko, A., Jäger, J., Jastrow, U., Kammering, R., Karstensen, S., Kaukher, A., Kay, H., Keil, B., Baboi, N., Klose, K., Kocharyan, V., Köpke, M., Körfer, M., Kook, W., Krause, B., Krebs, O., Kreis, S., Krivan, F., Kuhlmann, J., Balandin, V., Kuhlmann, M., Kube, G., Laarmann, T., Lechner, C., Lederer, S., Leuschner, A., Liebertz, D., Liebing, J., Liedtke, A., Lilje, L., Bargen, N von, Limberg, T., Lipka, D., Liu, B., Lorbeer, B., Ludwig, K., Mahn, H., Marinkovic, G., Martens, C., Marutzky, F., and Maslocv, M.
Subjects: ddc:530
Abstract: Extreme-ultraviolet to x-ray free-electron lasers (FELs) in operation for scientific applications are up to now single-user facilities. While most FELs generate around 100 photon pulses per second, FLASH at DESY can deliver almost two orders of magnitude more pulses in this time span due to its superconducting accelerator technology. This makes the facility a prime candidate to realize the next step in FELs—dividing the electron pulse trains into several FEL lines and delivering photon pulses to several users at the same time. Hence, FLASH has been extended with a second undulator line and self-amplified spontaneous emission (SASE) is demonstrated in both FELs simultaneously. FLASH can now deliverMHzpulse trains to two user experiments in parallel with individually selected photon beam characteristics. First results of the capabilities of this extension are shown with emphasis on independent variation of wavelength, repetition rate, and photon pulse length.
Published: 2016
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16. Studentische Partizipation bei der Entwicklung interprofessioneller Lehre für Gesundheitsstudiengänge

Author: Behrend, R, Maaz, A, Hitzblech, T, Höppner, H, Heinze, C, Peters, H, Behrend, R, Maaz, A, Hitzblech, T, Höppner, H, Heinze, C, and Peters, H
Published: 2016

17. Berlin in Motion: Interprofessional teaching and learning for students in the fields of medicine, occupational therapy, physiotherapy and nursing (INTER-M-E-P-P)

Author: Bohrer, A, Heinze, C, Höppner, H, Behrend, R, Czakert, J, Hitzblech, T, Kaufmann, I, Maaz, A, Räbiger, J, Peters, H, Bohrer, A, Heinze, C, Höppner, H, Behrend, R, Czakert, J, Hitzblech, T, Kaufmann, I, Maaz, A, Räbiger, J, and Peters, H
Abstract: Aim: The Berlin project "Interprofessional teaching and learning in medicine, occupational therapy, physiotherapy and nursing" (INTER-M-E-P-P) pursues the goal of developing and testing interprofessional courses in an exemplary manner, and then implement these into their regular study programs. Method: Under the direction of a steering committee of the participating institutions, professions and status groups, interprofessional courses were designed, carried out and evaluated. Specific to this project are the participation of students in the steering committee, and the accompanying of external supervision. The evaluation integrates the perspectives of all project participants, and combines quantitative and qualitative methods.Results: INTER-M-E-P-P established cooperative structures between the participating universities and programs. Three courses were designed, taught and evaluated in an interprofessional manner. The various curricula, organizational patterns and locations of the study paths led to a great need for resources in regard to planning and implementation. This process can be made difficult by any stereotypes or preconceptions inherent to those doing the planning; however, under external supervision, the individual professional viewpoints can still be broadened and enriched.Conclusion: A sustainable implementation of interprofessional education into the curricula of health science study programs is currently complicated by barriers such as different geographical locations and differing university regulations concerning study and testing. Implementation will require long-term support at the university as well as at political levels., Zielsetzung: Das Berliner Projekt "Interprofessionelles Lehren und Lernen in Medizin, Ergotherapie, Physiotherapie und Pflege" (INTER-M-E-P-P) verfolgt das Ziel, interprofessionelle Lehrveranstaltungen modellhaft zu entwickeln, zu erproben und in die Curricula der Studiengänge zu implementieren. Methodik: Unter der Leitung einer institutions-, professions- und statusübergreifenden Lenkungsgruppe werden interprofessionelle Lehrveranstaltungen konzipiert, durchgeführt und evaluiert. Spezifisch sind die studentische Partizipation in der Lenkungsgruppe und die Begleitung durch externe Supervision. Die Evaluation integriert die Perspektiven aller am Projekt Beteiligten und kombiniert qualitative und quantitative Methoden. Ergebnisse: INTER-M-E-P-P hat Strukturen zur Kooperation der beteiligten Hochschulen und Studiengänge aufgebaut. Drei Lehrveranstaltungen wurden interprofessionell konzipiert, durchgeführt und evaluiert. Die unterschiedliche curriculare, strukturelle und räumliche Verortung der Studiengänge führt zu einem hohen, ressourcenintensiven Planungs- und Umsetzungsaufwand. Stereotype und Rollenbilder der Planenden können den Prozess erschweren; unter externer Supervision jedoch die professionsspezifischen Blickwinkel erweitern und bereichern.Schlussfolgerung: Eine nachhaltige Implementierung von IPL in die Curricula der Gesundheitsstudiengänge ist derzeit durch Barrieren wie die räumliche Trennung und verschiedene Studien- und Prüfungsordnungen erschwert. Sie benötigt dauerhafte Unterstützungsstrukturen auf hochschulischer und politischer Ebene.
Published: 2016

18. Simultaneous operation of two soft x-ray free-electron lasers driven by one linear accelerator

Author: Faatz, B, primary, Plönjes, E, additional, Ackermann, S, additional, Agababyan, A, additional, Asgekar, V, additional, Ayvazyan, V, additional, Baark, S, additional, Baboi, N, additional, Balandin, V, additional, Bargen, N von, additional, Bican, Y, additional, Bilani, O, additional, Bödewadt, J, additional, Böhnert, M, additional, Böspflug, R, additional, Bonfigt, S, additional, Bolz, H, additional, Borges, F, additional, Borkenhagen, O, additional, Brachmanski, M, additional, Braune, M, additional, Brinkmann, A, additional, Brovko, O, additional, Bruns, T, additional, Castro, P, additional, Chen, J, additional, Czwalinna, M K, additional, Damker, H, additional, Decking, W, additional, Degenhardt, M, additional, Delfs, A, additional, Delfs, T, additional, Deng, H, additional, Dressel, M, additional, Duhme, H-T, additional, Düsterer, S, additional, Eckoldt, H, additional, Eislage, A, additional, Felber, M, additional, Feldhaus, J, additional, Gessler, P, additional, Gibau, M, additional, Golubeva, N, additional, Golz, T, additional, Gonschior, J, additional, Grebentsov, A, additional, Grecki, M, additional, Grün, C, additional, Grunewald, S, additional, Hacker, K, additional, Hänisch, L, additional, Hage, A, additional, Hans, T, additional, Hass, E, additional, Hauberg, A, additional, Hensler, O, additional, Hesse, M, additional, Heuck, K, additional, Hidvegi, A, additional, Holz, M, additional, Honkavaara, K, additional, Höppner, H, additional, Ignatenko, A, additional, Jäger, J, additional, Jastrow, U, additional, Kammering, R, additional, Karstensen, S, additional, Kaukher, A, additional, Kay, H, additional, Keil, B, additional, Klose, K, additional, Kocharyan, V, additional, Köpke, M, additional, Körfer, M, additional, Kook, W, additional, Krause, B, additional, Krebs, O, additional, Kreis, S, additional, Krivan, F, additional, Kuhlmann, J, additional, Kuhlmann, M, additional, Kube, G, additional, Laarmann, T, additional, Lechner, C, additional, Lederer, S, additional, Leuschner, A, additional, Liebertz, D, additional, Liebing, J, additional, Liedtke, A, additional, Lilje, L, additional, Limberg, T, additional, Lipka, D, additional, Liu, B, additional, Lorbeer, B, additional, Ludwig, K, additional, Mahn, H, additional, Marinkovic, G, additional, Martens, C, additional, Marutzky, F, additional, Maslocv, M, additional, Meissner, D, additional, Mildner, N, additional, Miltchev, V, additional, Molnar, S, additional, Mross, D, additional, Müller, F, additional, Neumann, R, additional, Neumann, P, additional, Nölle, D, additional, Obier, F, additional, Pelzer, M, additional, Peters, H-B, additional, Petersen, K, additional, Petrosyan, A, additional, Petrosyan, G, additional, Petrosyan, L, additional, Petrosyan, V, additional, Petrov, A, additional, Pfeiffer, S, additional, Piotrowski, A, additional, Pisarov, Z, additional, Plath, T, additional, Pototzki, P, additional, Prandolini, M J, additional, Prenting, J, additional, Priebe, G, additional, Racky, B, additional, Ramm, T, additional, Rehlich, K, additional, Riedel, R, additional, Roggli, M, additional, Röhling, M, additional, Rönsch-Schulenburg, J, additional, Rossbach, J, additional, Rybnikov, V, additional, Schäfer, J, additional, Schaffran, J, additional, Schlarb, H, additional, Schlesselmann, G, additional, Schlösser, M, additional, Schmid, P, additional, Schmidt, C, additional, Schmidt-Föhre, F, additional, Schmitz, M, additional, Schneidmiller, E, additional, Schöps, A, additional, Scholz, M, additional, Schreiber, S, additional, Schütt, K, additional, Schütz, U, additional, Schulte-Schrepping, H, additional, Schulz, M, additional, Shabunov, A, additional, Smirnov, P, additional, Sombrowski, E, additional, Sorokin, A, additional, Sparr, B, additional, Spengler, J, additional, Staack, M, additional, Stadler, M, additional, Stechmann, C, additional, Steffen, B, additional, Stojanovic, N, additional, Sychev, V, additional, Syresin, E, additional, Tanikawa, T, additional, Tavella, F, additional, Tesch, N, additional, Tiedtke, K, additional, Tischer, M, additional, Treusch, R, additional, Tripathi, S, additional, Vagin, P, additional, Vetrov, P, additional, Vilcins, S, additional, Vogt, M, additional, Wagner, A de Zubiaurre, additional, Wamsat, T, additional, Weddig, H, additional, Weichert, G, additional, Weigelt, H, additional, Wentowski, N, additional, Wiebers, C, additional, Wilksen, T, additional, Willner, A, additional, Wittenburg, K, additional, Wohlenberg, T, additional, Wortmann, J, additional, Wurth, W, additional, Yurkov, M, additional, Zagorodnov, I, additional, and Zemella, J, additional
Published: 2016
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19. Quasi-phase matching for high-average power high harmonic generation

Author: Höppner, H.
Abstract: The currently running free-electron lasers (FELs) are primarily base on selfamplified spontaneous emission (SASE). Due to its stochastic process the X-ray pulse parameters change from shot to shot. There is a great scientific interest in improving the X-ray pulse parameters, such as the pulse shape and pulse spectrum, delivered by this ultra-intense and ultrashort source. One promising approach is to seed the FEL with high harmonics generated by an external XUV-source. At the „Freie-Elektronen Laser Hamburg II“ (FLASH II) at the „Deutsche-Elektronensynchrotron“ in Hamburg, it is planned to implement an external laser based XUV-seeding source. In order to generate the required seed energy of ~1 nJ in a variable spectral range from 10 nm to 40 nm (XUV - extreme ultraviolet) at 100 kHz repetition rate, a new modular multi-nozzle XUV-source has been developed. The multi-nozzles create successive gas-jets in an open space geometry, enabling the nozzle to be used at high average power without a damage threshold. The multi-jet source enables high harmonic generation (HHG) in an inert gas by successive coherent superposition. In order to obtain coherent superposition, the phase between the fundamental laser frequency and the harmonics has to be adjusted between each single jet. The concept of quasi-phase-matching (QPM) is based on HHG-jets alternating with hydrogen jets, where the hydrogen acts as phase-matching medium to correct the phase acquired in the HHG-jet. Hydrogen is completely ionized at the used driver intensities ≥ 3 · 1014 W/cm² and therefore cannot contribute to the HHG-process. Atomic and plasma dispersion allow the control of the phase relationship between the fundamental and high harmonics by pressure tuning, in order to achieve coherent superposition of the generated harmonics in the multi-jet target. Proof of principle experiments exhibited significant enhancement for low average power driver lasers. In this thesis the macroscopic aspects for QPM are analyzed in a 1-d simulation. The results of the simulation provided the conditions for experimental tests of the dual-gas target at high repetition rates. The experimental part of this work has been accomplished at the „Institut für angewandte Physik” in Jena at a high power fiber amplifiers system with laser parameter: 400 μJ pulse energy, 580 fs pulse duration (FWHM), and 75 kHz repetition rate. For selected harmonics a maximal enhancement of the harmonic yield by a factor of 2 - 3 was achieved. Das wissenschaftliche Interesse an der Verbesserung der Pulsparameter von Freie-Elektronen Lasern (FEL) in Bezug auf Pulsform und Spektrum ist groß. Ein vielversprechender Ansatz ist das direkte "Seeden" des FEL‘s mit höheren Harmonischen durch eine externe XUV-Quelle. Für den Freie-Elektronen Laser Hamburg II (FLASH II) beim Deutsche-Elektronensynchrotron (DESY) in Hamburg ist eine derartige XUV-Quelle in der Planung vorgesehen. Um möglich effizient hohe Harmonische mit variablem Wellenlängenbereich von 10 nm bis 40 nm mit Wiederholrate von 100 kHz zu erzeugen, wurde eine neue HHG-Quelle auf Basis eines modularen multi-Düsen Systems entwickelt. Die Düsen erzeugen sukzessive Gasstrahlen im offenen Raum im Vakuum. Die offene Geometrie ist notwendig, um die durch die hohen Wiederholraten entstehende hohe Durchschnittsleistung ohne Zerstörschwelle nutzen zu können. Die multi-Strahl-Quelle erlaubt die sukzessive Erzeugung von hohen Harmonischen in Edelgas, welche kohärent überlagert werden. Um die konstruktive Überlagerung zu gewährleisten, muss die Phasenbeziehung zwischen Fundamentaler und Harmonischen nach jedem Einzelstrahl angepasst werden (Quasi-Phasen-Anpassung). Dieses Verfahren der Quasi-Phasen-Anpassung wird mit einem dual Gas System realisiert. Zwischen die einzelnen HHG-Gasstrahlen wird jeweils ein Wasserstoff-Gasstrahl eingefügt. Im Wasserstoff lassen sich ab Intensitäten von > 3·1014 W/cm² wegen vollständiger Ionisation keine höheren Harmonischen mehr erzeugen. Durch die Plasma Dispersion lässt sich die Phasenbeziehung zwischen Fundamentaler und Harmonischen wiederherstellen und somit destruktive Interferenz vermeiden. Mit dieser multi-Strahl-Quelle lässt sich die harmonische Ausbeute nachweislich verbessern. Im Rahmen der Masterthesis wurde neben einer eindimensionalen Simulation, die multi-Strahl-Quelle erstmalig bei hohen Wiederholraten getestet. Der experimentelle Teil der Arbeit wurde am Institut für angewandte Physik (IAP) in Jena an einem Hochleistungs-Faserverstärker bei 400 μJ Pulsenergie, 580 fs Pulsdauer (FWHM) bei einer Pulswiederholrate von 75 kHz getestet. Es konnte für vereinzelte Harmonische eine maximale Verbesserung der Photonenausbeute um den Faktor 2-3 erzielt werden.
Published: 2013

20. An optical parametric chirped-pulse amplifier for seeding high repetition rate free-electron lasers

Author: Höppner, H, primary, Hage, A, additional, Tanikawa, T, additional, Schulz, M, additional, Riedel, R, additional, Teubner, U, additional, Prandolini, M J, additional, Faatz, B, additional, and Tavella, F, additional
Published: 2015
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21. Role of Temperature on Flux Trap Behavior in < 100 > Pb Cylindrical Sample: Polarized Neutron Radiography Investigation

Author: Dhiman, Indu, primary, Ebrahimi, O., additional, Karakas, N., additional, Höppner, H., additional, Ziesche, R., additional, and Treimer, Wolfgang, additional
Published: 2015
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22. Thermal properties of borate crystals for high power optical parametric chirped-pulse amplification

Author: Riedel, R., primary, Rothhardt, J., additional, Beil, K., additional, Gronloh, B., additional, Klenke, A., additional, Höppner, H., additional, Schulz, M., additional, Teubner, U., additional, Kränkel, C., additional, Limpert, J., additional, Tünnermann, A., additional, Prandolini, M.J., additional, and Tavella, F., additional
Published: 2014
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23. Umrisse einer neuen Gesundheitsbildungspolitik

Author: Sottas, B, Höppner, H, Kickbusch, I, Pelikan, J, Probst, J, Sottas, B, Höppner, H, Kickbusch, I, Pelikan, J, and Probst, J
Published: 2013

24. Design considerations for a high power, ultrabroadband optical parametric chirped-pulse amplifier

Author: Prandolini, M. J., primary, Riedel, R., additional, Schulz, M., additional, Hage, A., additional, Höppner, H., additional, and Tavella, F., additional
Published: 2014
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25. Long-term stabilization of high power optical parametric chirped-pulse amplifiers

Author: Riedel, R., primary, Schulz, M., additional, Prandolini, M. J., additional, Hage, A., additional, Höppner, H., additional, Gottschall, T., additional, Limpert, J., additional, Drescher, M., additional, and Tavella, F., additional
Published: 2013
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26. Role of Temperature on Flux Trap Behavior in < 100 > Pb Cylindrical Sample: Polarized Neutron Radiography Investigation

Author: Dhiman, Indu, Ebrahimi, O., Karakas, N., Höppner, H., Ziesche, R., and Treimer, Wolfgang
Subjects: Theories and models of superconducting state, Condensed Matter::Superconductivity, Magnetic properties including vortex structures and related phenomena, Neutron imaging and neutron tomography, Physics and Astronomy(all)
Abstract: The evolution of flux trap behavior at low temperature (the intermediate state) in high purity Lead samples, both in single crystal with < 100 > orientation and polycrystalline form, is investigated using field cooled (FC) neutron tomography measurements. Reported measurements are carried out for 0∘ and 90∘ sample axis orientation with respect to the external magnetic field. For both< 100 > Pb single crystal as well as polycrystalline sample development of fringe pattern below T < Tc (at 5K) is observed. This shows magnetic field trapped within the sample. On increasing the temperature to 7.5K for T > Tc, fringe pattern inside the sample disappears, indicating that the sample attains a normal state. Further comparison of mosaic spread values for < 100 > Pb crystal and our previously reported < 110 > Pb crystal indicate the feeble role played by dislocations and / or defects [Phys. Rev. B 85 184522 (2012)]. Interestingly, not only the field cooled superconducting state appears distinct for each sample, dependent on the crystal structure - single crystal or polycrystalline, but also on the applied magnetic field orientation with respect to the crystallographic sample axis.
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27. The High Energy Density Scientific Instrument at the European XFEL

Author: M. Hassan, Lennart Wollenweber, A. Laso Garcia, I. Thorpe, Ulrich Schramm, M. Toncian, Hauke Höppner, Motoaki Nakatsutsumi, Karen Appel, J. Hauser, T. Herrmannsdörfer, Clemens Prescher, T. Feldmann, S. Dietrich, M. Foese, Mohammadreza Banjafar, K. Sukharnikov, Carsten Baehtz, M. Röper, Ulf Zastrau, P. Talkovski, W. Seidel, Lewis Batchelor, S. Findeisen, O. Baehr, T. Toncian, P. Kaever, Erik Brambrink, H.-O. Engel, D. Fulla-Marsa, E.-C. Martens, J. Dreyer, Johannes Kaa, A. Schmidt, Valerio Cerantola, M. Makita, J. P. Schwinkendorf, A. Schropp, C. Strohm, Thomas E. Cowan, A. Pelka, Markus O. Schoelmerich, Hanns-Peter Liermann, H. Damker, Emma McBride, T. R. Preston, D. Möller, Sebastian Göde, S. Di Dio Cafiso, Zuzana Konôpková, J. Mainberger, Thomas Tschentscher, K. Knöfel, Sh. Yamamoto, C. Plueckthun, A. Berghäuser, Zastrau, U, Appel, K, Baehtz, C, Baehr, O, Batchelor, L, Berghäuser, A, Banjafar, M, Brambrink, E, Cerantola, V, Cowan, T, Damker, H, Dietrich, S, Di Dio Cafiso, S, Dreyer, J, Engel, H, Feldmann, T, Findeisen, S, Foese, M, Fulla-Marsa, D, Göde, S, Hassan, M, Hauser, J, Herrmannsdörfer, T, Höppner, H, Kaa, J, Kaever, P, Knöfel, K, Konôpková, Z, Laso García, A, Liermann, H, Mainberger, J, Makita, M, Martens, E, Mcbride, E, Möller, D, Nakatsutsumi, M, Pelka, A, Plueckthun, C, Prescher, C, Preston, T, Röper, M, Schmidt, A, Seidel, W, Schwinkendorf, J, Schoelmerich, M, Schramm, U, Schropp, A, Strohm, C, Sukharnikov, K, Talkovski, P, Thorpe, I, Toncian, M, Toncian, T, Wollenweber, L, Yamamoto, S, and Tschentscher, T
Subjects: Pulse repetition frequency, Nuclear and High Energy Physics, Astrophysics::High Energy Astrophysical Phenomena, law.invention, high-pressure science, Optics, law, ddc:550, relativistic laser-matter interaction, Spontaneous emission, Instrumentation, Scientific instrument, Physics, high energy density, Radiation, Spectrometer, business.industry, relativistic laser–matter interaction, Warm dense matter, Laser, Research Papers, warm dense matter, State of matter, X-ray free-electron laser, X-ray free-electron lasers, business, Ultrashort pulse
Abstract: Journal of synchrotron radiation 28(5), 28 (2021). doi:10.1107/S1600577521007335, The European XFEL delivers up to 27000 intense (>1012 photons) pulses per second, of ultrashort (≤50 fs) and transversely coherent X-ray radiation, at a maximum repetition rate of 4.5 MHz. Its unique X-ray beam parameters enable groundbreaking experiments in matter at extreme conditions at the High Energy Density (HED) scientific instrument. The performance of the HED instrument during its first two years of operation, its scientific remit, as well as ongoing installations towards full operation are presented. Scientific goals of HED include the investigation of extreme states of matter created by intense laser pulses, diamond anvil cells, or pulsed magnets, and ultrafast X-ray methods that allow their diagnosis using self-amplified spontaneous emission between 5 and 25 keV, coupled with X-ray monochromators and optional seeded beam operation. The HED instrument provides two target chambers, X-ray spectrometers for emission and scattering, X-ray detectors, and a timing tool to correct for residual timing jitter between laser and X-ray pulses., Published by Wiley-Blackwell, [S.l.]
Published: 2021
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28. Cylindrical compression of thin wires by irradiation with a Joule-class short-pulse laser.

Author: Laso Garcia A, Yang L, Bouffetier V, Appel K, Baehtz C, Hagemann J, Höppner H, Humphries O, Kluge T, Mishchenko M, Nakatsutsumi M, Pelka A, Preston TR, Randolph L, Zastrau U, Cowan TE, Huang L, and Toncian T
Abstract: Equation of state measurements at Jovian or stellar conditions are currently conducted by dynamic shock compression driven by multi-kilojoule multi-beam nanosecond-duration lasers. These experiments require precise design of the target and specific tailoring of the spatial and temporal laser profiles to reach the highest pressures. At the same time, the studies are limited by the low repetition rate of the lasers. Here, we show that by the irradiation of a thin wire with single-beam Joule-class short-pulse laser, a converging cylindrical shock is generated compressing the wire material to conditions relevant to the above applications. The shockwave was observed using Phase Contrast Imaging employing a hard X-ray Free Electron Laser with unprecedented temporal and spatial sensitivity. The data collected for Cu wires is in agreement with hydrodynamic simulations of an ablative shock launched by highly impulsive and transient resistive heating of the wire surface. The subsequent cylindrical shockwave travels toward the wire axis and is predicted to reach a compression factor of 9 and pressures above 800 Mbar. Simulations for astrophysical relevant materials underline the potential of this compression technique as a new tool for high energy density studies at high repetition rates., (© 2024. The Author(s).)
Published: 2024
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29. Non-thermal structural transformation of diamond driven by x-rays.

Author: Heimann P, Hartley NJ, Inoue I, Tkachenko V, Antoine A, Dorchies F, Falcone R, Gaudin J, Höppner H, Inubushi Y, Kapcia KJ, Lee HJ, Lipp V, Martinez P, Medvedev N, Tavella F, Toleikis S, Yabashi M, Yabuuchi T, Yamada J, and Ziaja B
Abstract: Intense x-ray pulses can cause the non-thermal structural transformation of diamond. At the SACLA XFEL facility, pump x-ray pulses triggered this phase transition, and probe x-ray pulses produced diffraction patterns. Time delays were observed from 0 to 250 fs, and the x-ray dose varied from 0.9 to 8.0 eV/atom. The intensity of the (111), (220), and (311) diffraction peaks decreased with time, indicating a disordering of the crystal lattice. From a Debye-Waller analysis, the rms atomic displacements perpendicular to the (111) planes were observed to be significantly larger than those perpendicular to the (220) or (311) planes. At a long time delay of 33 ms, graphite (002) diffraction indicates that graphitization did occur above a threshold dose of 1.2 eV/atom. These experimental results are in qualitative agreement with XTANT+ simulations using a hybrid model based on density-functional tight-binding molecular dynamics., Competing Interests: The authors have no conflicts to disclose., (© 2023 Author(s).)
Published: 2023
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30. The High Energy Density Scientific Instrument at the European XFEL.

Author: Zastrau U, Appel K, Baehtz C, Baehr O, Batchelor L, Berghäuser A, Banjafar M, Brambrink E, Cerantola V, Cowan TE, Damker H, Dietrich S, Di Dio Cafiso S, Dreyer J, Engel HO, Feldmann T, Findeisen S, Foese M, Fulla-Marsa D, Göde S, Hassan M, Hauser J, Herrmannsdörfer T, Höppner H, Kaa J, Kaever P, Knöfel K, Konôpková Z, Laso García A, Liermann HP, Mainberger J, Makita M, Martens EC, McBride EE, Möller D, Nakatsutsumi M, Pelka A, Plueckthun C, Prescher C, Preston TR, Röper M, Schmidt A, Seidel W, Schwinkendorf JP, Schoelmerich MO, Schramm U, Schropp A, Strohm C, Sukharnikov K, Talkovski P, Thorpe I, Toncian M, Toncian T, Wollenweber L, Yamamoto S, and Tschentscher T
Abstract: The European XFEL delivers up to 27000 intense (>10 12 photons) pulses per second, of ultrashort (≤50 fs) and transversely coherent X-ray radiation, at a maximum repetition rate of 4.5 MHz. Its unique X-ray beam parameters enable groundbreaking experiments in matter at extreme conditions at the High Energy Density (HED) scientific instrument. The performance of the HED instrument during its first two years of operation, its scientific remit, as well as ongoing installations towards full operation are presented. Scientific goals of HED include the investigation of extreme states of matter created by intense laser pulses, diamond anvil cells, or pulsed magnets, and ultrafast X-ray methods that allow their diagnosis using self-amplified spontaneous emission between 5 and 25 keV, coupled with X-ray monochromators and optional seeded beam operation. The HED instrument provides two target chambers, X-ray spectrometers for emission and scattering, X-ray detectors, and a timing tool to correct for residual timing jitter between laser and X-ray pulses., (open access.)
Published: 2021
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31. Effect of Auger recombination on transient optical properties in XUV and soft X-ray irradiated silicon nitride.

Author: Tkachenko V, Lipp V, Büscher M, Capotondi F, Höppner H, Medvedev N, Pedersoli E, Prandolini MJ, Rossi GM, Tavella F, Toleikis S, Windeler M, Ziaja B, and Teubner U
Abstract: Spatially encoded measurements of transient optical transmissivity became a standard tool for temporal diagnostics of free-electron-laser (FEL) pulses, as well as for the arrival time measurements in X-ray pump and optical probe experiments. The modern experimental techniques can measure changes in optical coefficients with a temporal resolution better than 10 fs. This, in an ideal case, would imply a similar resolution for the temporal pulse properties and the arrival time jitter between the FEL and optical laser pulses. However, carrier transport within the material and out of its surface, as well as carrier recombination may, in addition, significantly decrease the number of carriers. This would strongly affect the transient optical properties, making the diagnostic measurement inaccurate. Below we analyze in detail the effects of those processes on the optical properties of XUV and soft X-ray irradiated Si[Formula: see text]N[Formula: see text], on sub-picosecond timescales. Si[Formula: see text]N[Formula: see text] is a wide-gap insulating material widely used for FEL pulse diagnostics. Theoretical predictions are compared with the published results of two experiments at FERMI and LCLS facilities, and with our own recent measurement. The comparison indicates that three body Auger recombination strongly affects the optical response of Si[Formula: see text]N[Formula: see text] after its collisional ionization stops. By deconvolving the contribution of Auger recombination, in future applications one could regain a high temporal resolution for the reconstruction of the FEL pulse properties measured with a Si[Formula: see text]N[Formula: see text]-based diagnostics tool.
Published: 2021
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32. Human-Robotic Variable-Stiffness Grasps of Small-Fruit Containers Are Successful Even Under Severely Impaired Sensory Feedback.

Author: Haas M, Friedl W, Stillfried G, and Höppner H
Abstract: Application areas of robotic grasping extend to delicate objects like groceries. The intrinsic elasticity offered by variable-stiffness actuators (VSA) appears to be promising in terms of being able to adapt to the object shape, to withstand collisions with the environment during the grasp acquisition, and to resist the weight applied to the fingers by a lifted object during the actual grasp. It is hypothesized that these properties are particularly useful in the absence of high-quality sensory feedback, which would otherwise be able to guide the shape adaptation and collision avoidance, and that in this case, VSA hands perform better than hands with fixed stiffness. This hypothesis is tested in an experiment where small-fruit containers are picked and placed using a newly developed variable-stiffness robotic hand. The grasp performance is measured under different sensory feedback conditions: full or impaired visual feedback, full or impaired force feedback. The hand is switched between a variable-stiffness mode and two fixed-stiffness modes. Strategies for modulating the stiffness and exploiting environmental constraints are observed from human operators that control the robotic hand. The results show consistently successful grasps under all stiffness and feedback conditions. However, the performance is affected by the amount of available visual feedback. Different stiffness modes turn out to be beneficial in different feedback conditions and with respect to different performance criteria, but a general advantage of VSA over fixed stiffness cannot be shown for the present task. Guidance of the fingers along cracks and gaps is observed, which may inspire the programming of autonomously grasping robots.
Published: 2018
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33. Human's Capability to Discriminate Spatial Forces at the Big Toe.

Author: Hagengruber A, Höppner H, and Vogel J
Abstract: A key factor for reliable object manipulation is the tactile information provided by the skin of our hands. As this sensory information is so essential in our daily life it should also be provided during teleoperation of robotic devices or in the control of myoelectric prostheses. It is well-known that feeding back the tactile information to the user can lead to a more natural and intuitive control of robotic devices. However, in some applications it is difficult to use the hands as natural feedback channels since they may already be overloaded with other tasks or, e.g., in case of hand prostheses not accessible at all. Many alternatives for tactile feedback to the human hand have already been investigated. In particular, one approach shows that humans can integrate uni-directional (normal) force feedback at the toe into their sensorimotor-control loop. Extending this work, we investigate the human's capability to discriminate spatial forces at the bare front side of their toe. A state-of-the-art haptic feedback device was used to apply forces with three different amplitudes-2 N, 5 N, and 8 N-to subjects' right big toes. During the experiments, different force stimuli were presented, i.e., direction of the applied force was changed, such that tangential components occured. In total the four directions up (distal), down (proximal), left (medial), and right (lateral) were tested. The proportion of the tangential force was varied corresponding to a directional change of 5° to 25° with respect to the normal force. Given these force stimuli, the subjects' task was to identify the direction of the force change. We found the amplitude of the force as well as the proportion of tangential forces to have a significant influence on the success rate. Furthermore, the direction right showed a significantly different successrate from all other directions. The stimuli with a force amplitude of 8 N achieved success rates over 89% in all directions. The results of the user study provide evidence that the subjects were able to discriminate spatial forces at their toe within defined force amplitudes and tangential proportion.
Published: 2018
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34. Elastic Elements in a Wrist Prosthesis for Drumming Reduce Muscular Effort, but Increase Imprecision and Perceived Stress.

Author: Stillfried G, Stepper J, Neppl H, Vogel J, and Höppner H
Abstract: Recently, progress has been made in the development of mechanical joints with variable intrinsic stiffness, opening up the search for application areas of such variable-stiffness joints. By varying the stiffness of its joints, the resonant frequency of a system can be tuned to perform cyclical tasks most energy-efficiently, making the variable-stiffness joint a candidate element for an advanced prosthetic device specifically designed for the cyclical task of drumming. A prerequisite for a successful variable-stiffness drumming prosthesis is the ability of human drummers to profitably employ different stiffness levels for playing different beats. In this pilot study, 29 able-bodied subjects (20 drumming novices and 9 experts) wear a cuff on the forearm, to which a drumstick is connected using changeable adapters, consisting of several leaf springs with different stiffness and one maximally stiff connection element. The subjects are asked to play simple regular drum beats at different frequencies, one of which is the resonant frequency of the adapter-drumstick system. The subject's performance of each drumming task is rated in terms of accuracy and precision, and the effort is measured using questionnaires for the perceived stress as well as electromyography (EMG) for the muscular activity. The experiments show that using springs instead of the stiff connection leads to lower muscular activity, indicating that humans are able to use the energy-storing capabilities of the springs, or that muscular activity is reduced due to the lower mass of the springs. However, the perceived stress is increased and the novices' performance lowered, possibly due to a higher cerebral load for controlling the elastic system. The hypothesis that "matching the resonant frequency of the spring-drumstick system to the desired frequency leads to better performance and lower effort" is not confirmed. Possible explanations are discussed. In conclusion, a series-elastic element appears to lower the muscular effort of drumming, while a stiff connection appears to minimize the mental load and has a positive effect on the performance of drumming novices.
Published: 2018
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35. Independent Measurement of PEF Values.

Author: Höppner H
Subjects: Female, Humans, Pregnancy, Pregnancy Complications therapy
Published: 2018
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36. Key Insights into Hand Biomechanics: Human Grip Stiffness Can Be Decoupled from Force by Cocontraction and Predicted from Electromyography.

Author: Höppner H, Große-Dunker M, Stillfried G, Bayer J, and van der Smagt P
Abstract: We investigate the relation between grip force and grip stiffness for the human hand with and without voluntary cocontraction. Apart from gaining biomechanical insight, this issue is particularly relevant for variable-stiffness robotic systems, which can independently control the two parameters, but for which no clear methods exist to design or efficiently exploit them. Subjects were asked in one task to produce different levels of force, and stiffness was measured. As expected, this task reveals a linear coupling between force and stiffness. In a second task, subjects were then asked to additionally decouple stiffness from force at these force levels by using cocontraction. We measured the electromyogram from relevant groups of muscles and analyzed the possibility to predict stiffness and force. Optical tracking was used for avoiding wrist movements. We found that subjects were able to decouple grip stiffness from force when using cocontraction on average by about 20% of the maximum measured stiffness over all force levels, while this ability increased with the applied force. This result contradicts the force-stiffness behavior of most variable-stiffness actuators. Moreover, we found the thumb to be on average twice as stiff as the index finger and discovered that intrinsic hand muscles predominate our prediction of stiffness, but not of force. EMG activity and grip force allowed to explain 72 ± 12% of the measured variance in stiffness by simple linear regression, while only 33 ± 18% variance in force. Conclusively the high signal-to-noise ratio and the high correlation to stiffness of these muscles allow for a robust and reliable regression of stiffness, which can be used to continuously teleoperate compliance of modern robotic hands.
Published: 2017
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37. Berlin in Motion: Interprofessional teaching and learning for students in the fields of medicine, occupational therapy, physiotherapy and nursing (INTER-M-E-P-P).

Author: Bohrer A, Heinze C, Höppner H, Behrend R, Czakert J, Hitzblech T, Kaufmann I, Maaz A, Räbiger J, and Peters H
Subjects: Berlin, Humans, Physical Therapy Modalities, Students, Education, Nursing, Interprofessional Relations, Occupational Therapy education
Abstract: Aim: The Berlin project "Interprofessional teaching and learning in medicine, occupational therapy, physiotherapy and nursing" (INTER-M-E-P-P) pursues the goal of developing and testing interprofessional courses in an exemplary manner, and then implement these into their regular study programs., Method: Under the direction of a steering committee of the participating institutions, professions and status groups, interprofessional courses were designed, carried out and evaluated. Specific to this project are the participation of students in the steering committee, and the accompanying of external supervision. The evaluation integrates the perspectives of all project participants, and combines quantitative and qualitative methods., Results: INTER-M-E-P-P established cooperative structures between the participating universities and programs. Three courses were designed, taught and evaluated in an interprofessional manner. The various curricula, organizational patterns and locations of the study paths led to a great need for resources in regard to planning and implementation. This process can be made difficult by any stereotypes or preconceptions inherent to those doing the planning; however, under external supervision, the individual professional viewpoints can still be broadened and enriched., Conclusion: A sustainable implementation of interprofessional education into the curricula of health science study programs is currently complicated by barriers such as different geographical locations and differing university regulations concerning study and testing. Implementation will require long-term support at the university as well as at political levels.
Published: 2016
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38. Task dependency of grip stiffness--a study of human grip force and grip stiffness dependency during two different tasks with same grip forces.

Author: Höppner H, McIntyre J, and van der Smagt P
Subjects: Adult, Fingers physiology, Humans, Male, Middle Aged, Models, Anatomic, Muscles physiology, Tendons physiology, Wrist physiology, Hand Strength physiology, Models, Statistical, Psychomotor Performance physiology
Abstract: It is widely known that the pinch-grip forces of the human hand are linearly related to the weight of the grasped object. Less is known about the relationship between grip force and grip stiffness. We set out to determine variations to these dependencies in different tasks with and without visual feedback. In two different settings, subjects were asked to (a) grasp and hold a stiffness-measuring manipulandum with a predefined grip force, differing from experiment to experiment, or (b) grasp and hold this manipulandum of which we varied the weight between trials in a more natural task. Both situations led to grip forces in comparable ranges. As the measured grip stiffness is the result of muscle and tendon properties, and since muscle/tendon stiffness increases more-or-less linearly as a function of muscle force, we found, as might be predicted, a linear relationship between grip force and grip stiffness. However, the measured stiffness ranges and the increase of stiffness with grip force varied significantly between the two tasks. Furthermore, we found a strong correlation between regression slope and mean stiffness for the force task which we ascribe to a force stiffness curve going through the origin. Based on a biomechanical model, we attributed the difference between both tasks to changes in wrist configuration, rather than to changes in cocontraction. In a new set of experiments where we prevent the wrist from moving by fixing it and resting it on a pedestal, we found subjects exhibiting similar stiffness/force characteristics in both tasks.
Published: 2013
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39. Regulation of HMG-CoA synthase and HMG-CoA reductase by insulin and epidermal growth factor in HaCaT keratinocytes.

Author: Harris IR, Höppner H, Siefken W, Farrell AM, and Wittern KP
Subjects: Binding Sites physiology, Calcimycin pharmacology, Cell Line, Humans, Hydroxymethylglutaryl-CoA Synthase genetics, Ionophores pharmacology, Promoter Regions, Genetic drug effects, Promoter Regions, Genetic physiology, RNA, Messenger metabolism, Transcription Factor AP-1 metabolism, Epidermal Growth Factor pharmacology, Hydroxymethylglutaryl CoA Reductases metabolism, Hydroxymethylglutaryl-CoA Synthase metabolism, Insulin pharmacology, Keratinocytes drug effects, Keratinocytes enzymology
Abstract: Synthesis of cholesterol, via the isoprenoid/mevalonate pathway, is required for keratinocyte growth and differentiation, and maintenance of the stratum corneum lipid lamellae. 3-hydroxy-3-methylglutaryl coenzyme A synthase catalyzes the first step in isoprenoid/mevalonate synthesis and under some conditions controls the flux into the pathway. We have investigated whether selected growth factors and hormones could increase 3-hydroxy-3-methylglutaryl coenzyme A synthase mRNA in keratinocytes. Northern blotting was used to demonstrate that 10 microg per ml insulin and 0.1 microg per ml epidermal growth factor both increased steady-state levels of 3-hydroxy-3-methylglutaryl coenzyme A synthase mRNA by 2.5 and 6-fold, respectively. Epidermal growth factor and insulin also increased 3-hydroxy-3-methylglutaryl coenzyme A reductase enzyme activity. 3-hydroxy-3-methylglutaryl coenzyme A synthase promoter activity in a luciferase reporter construct was increased 2-fold by insulin and 2.9-fold by epidermal growth factor. When a mutation in the sterol regulatory element was introduced into the 3-hydroxy-3-methylglutaryl coenzyme A synthase promoter, activity was not increased by insulin, but was increased by epidermal growth factor. Mutation of an AP-1 site in the 3-hydroxy-3-methylglutaryl coenzyme A synthase promoter did not affect the increase in activity following treatment with insulin or epidermal growth factor. Therefore, 3-hydroxy-3-methylglutaryl coenzyme A synthase expression in keratinocytes is regulated by insulin and epidermal growth factor by different mechanisms. These results suggest a role for hormones and growth factors in the control of epidermal cholesterol synthesis.
Published: 2000
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