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107 results on '"Lichter, S"'

1. The Design, Construction, and Commissioning of the KATRIN Experiment

Author

Aker, M., Altenmüller, K., Amsbaugh, J. F., Arenz, M., Babutzka, M., Bast, J., Bauer, S., Bechtler, H., Beck, M., Beglarian, A., Behrens, J., Bender, B., Berendes, R., Berlev, A., Besserer, U., Bettin, C., Bieringer, B., Blaum, K., Block, F., Bobien, S., Bohn, J., Bokeloh, K., Bolz, H., Bornschein, B., Bornschein, L., Böttcher, M., Bouquet, H., Boyd, N. M., Brunst, T., Burritt, T. H., Caldwell, T. S., Chaoui, Z., Chilingaryan, S., Choi, W., Corona, T. J., Cox, G. A., Debowski, K., Deffert, M., Descher, M., Barrero, D. Díaz, Doe, P. J., Dragoun, O., Drexlin, G., Dunmore, J. A., Dyba, S., Edzards, F., Eichelhardt, F., Eitel, K., Ellinger, E., Engel, R., Enomoto, S., Erhard, M., Eversheim, D., Fedkevych, M., Felden, A., Fischer, S., Formaggio, J. A., Fränkle, F. M., Franklin, G. B., Frenzel, H., Friedel, F., Fulst, A., Gauda, K., Gehring, R., Gil, W., Glück, F., Görhardt, S., Grimm, J., Grohmann, S., Groh, S., Grössle, R., Gumbsheimer, R., Hackenjos, M., Häßler, D., Hannen, V., Harms, F., Harper, G. C., Hartmann, J., Haußmann, N., Heizmann, F., Helbing, K., Held, M., Hickford, S., Hilk, D., Hillen, B., Hiller, R., Hillesheimer, D., Hinz, D., Höhn, T., Holzmann, S., Horn, S., Hötzel, M., Houdy, T., Howe, M. A., Huber, A., James, T., Jansen, A., Kaiser, M., Karl, C., Kazachenko, O., Kellerer, J., Kippenbrock, L., Kleesiek, M., Kleifges, M., Kleinfeller, J., Klein, M., Köllenberger, L., Kopmann, A., Korzeczek, M., Kosmider, A., Kovalík, A., Krasch, B., Krause, H., Kraus, M., Kuckert, L., Kumb, A., Kunka, N., Lasserre, T., La Cascio, L., Lebeda, O., Leber, M. L., Lehnert, B., Leiber, B., Letnev, J., Lewis, R. J., Le, T. L., Lichter, S., Lokhov, A., Poyato, J. M. Lopez, Machatschek, M., Malcherek, E., Mark, M., Marsteller, A., Martin, E. L., Mehret, K., Meloni, M., Melzer, C., Menshikov, A., Mertens, S., Minter, L. I., Monreal, B., Mostafa, J., Müller, K., Myers, A. W., Naumann, U., Neumann, H., Niemes, S., Oelpmann, P., Off, A., Ortjohann, H. -W., Osipowicz, A., Ostrick, B., Parno, D. S., Peterson, D. A., Plischke, P., Poon, A. W. P., Prall, M., Priester, F., Ranitzsch, P. C. -O., Reich, J., Renschler, P., Rest, O., Rinderspacher, R., Robertson, R. G. H., Rodejohann, W., Rodenbeck, C., Rohr, P., Röllig, M., Röttele, C., Rupp, S., Ryšavý, M., Sack, R., Saenz, A., Sagawe, M., Schäfer, P., Schaller, A., Schimpf, L., Schlösser, K., Schlösser, M., Schlüter, L., Schneidewind, S., Schön, H., Schönung, K., Schrank, M., Schulz, B., Schwarz, J., Šefčík, M., Seitz-Moskaliuk, H., Seller, W., Sibille, V., Siegmann, D., Slezák, M., Spanier, F., Steidl, M., Sturm, M., Sun, M., Tcherniakhovski, D., Telle, H. H., Thorne, L. A., Thümmler, T., Titov, N., Tkachev, I., Trost, N., Valerius, K., VanDevender, B. A., Van Wechel, T. D., Vénos, D., Verbeek, A., Vianden, R., Hernández, A. P. Vizcaya, Vogt, K., Wall, B. L., Wandkowsky, N., Weber, M., Weingardt, H., Weinheimer, C., Weiss, C., Welte, S., Wendel, J., Wierman, K. J., Wilkerson, J. F., Wolf, J., Wüstling, S., Xu, W., Yen, Y. -R., Zacher, M., Zadoroghny, S., Zboril, M., and Zeller, G.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

The KArlsruhe TRItium Neutrino (KATRIN) experiment, which aims to make a direct and model-independent determination of the absolute neutrino mass scale, is a complex experiment with many components. More than 15 years ago, we published a technical design report (TDR) [https://publikationen.bibliothek.kit.edu/270060419] to describe the hardware design and requirements to achieve our sensitivity goal of 0.2 eV at 90% C.L. on the neutrino mass. Since then there has been considerable progress, culminating in the publication of first neutrino mass results with the entire beamline operating [arXiv:1909.06048]. In this paper, we document the current state of all completed beamline components (as of the first neutrino mass measurement campaign), demonstrate our ability to reliably and stably control them over long times, and present details on their respective commissioning campaigns., Comment: Added missing acknowledgement, corrected performance statement in chapter 4.2.5, updated author list and references

Published
2021
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2. Suppression of Penning discharges between the KATRIN spectrometers

Author

Aker, M., Altenmüller, K., Beglarian, A., Behrens, J., Berlev, A., Besserer, U., Blaum, K., Block, F., Bobien, S., Bornschein, B., Bornschein, L., Bouquet, H., Brunst, T., Caldwell, T. S., Chilingaryan, S., Choi, W., Debowski, K., Deffert, M., Descher, M., Barrero, D. Díaz, Doe, P. J., Dragoun, O., Drexlin, G., Dyba, S., Eitel, K., Ellinger, E., Engel, R., Enomoto, S., Eversheim, D., Fedkevych, M., Felden, A., Formaggio, J. A., Fränkle, F., Franklin, G. B., Frankrone, H., Friedel, F., Fulst, A., Gauda, K., Gil, W., Glück, F., Grohmann, S., Grössle, R., Gumbsheimer, R., Hackenjos, M., Hannen, V., Hartmann, J., Haußmann, N., Heizmann, F., Heizmann, J., Helbing, K., Hickford, S., Hillesheimer, D., Hinz, D., Höhn, T., Holzapfel, B., Holzmann, S., Houdy, T., Jansen, A., Karl, C., Kellerer, J., Kernert, N., Kippenbrock, L., Klein, M., Köhler, C., Köllenberger, L., Kopmann, A., Korzeczek, M., Kovalík, A., Krasch, B., Krause, H., Kuffner, B., Kunka, N., Lasserre, T., La Cascio, L., Lebeda, O., Lehnert, B., Letnev, J., Leven, F., Le, T. L., Lichter, S., Lokhov, A., Machatschek, M., Malcherek, E., Marsteller, A., Martin, E. L., Melzer, C., Menshikov, A., Mertens, S., Monreal, B., Müller, K., Naumann, U., Neumann, H., Niemes, S., Noe, M., Ortjohann, H. -W., Osipowicz, A., Otten, E., Parno, D. S., Pollithy, A., Poon, A. W. P., Poyato, J. M. L., Priester, F., Ranitzsch, P. C. -O., Rest, O., Rinderspacher, R., Robertson, R. G. H., Rodenbeck, C., Rohr, P., Röllig, M., Röttele, C., Ryšavý, M., Sack, R., Saenz, A., Schäfer, P., Schimpf, L., Schlösser, K., Schlösser, M., Schlüter, L., Schrank, M., Schulz, B., Seitz-Moskaliuk, H., Seller, W., Sibille, V., Siegmann, D., Slezák, M., Spanier, F., Steidl, M., Steven, M., Sturm, M., Suesser, M., Sun, M., Tcherniakhovski, D., Telle, H. H., Thorne, L. A., Thümmler, T., Titov, N., Tkachev, I., Trost, N., Valerius, K., Vénos, D., Vianden, R., Hernández, A. P. Vizcaya, Weber, M., Weinheimer, C., Weiss, C., Welte, S., Wendel, J., Wilkerson, J. F., Wolf, J., Wüstling, S., Xu, W., Yen, Y. -R., Zadoroghny, S., and Zeller, G.

Subjects
Physics - Instrumentation and Detectors
Abstract

The KArlsruhe TRItium Neutrino experiment (KATRIN) aims to determine the effective electron (anti)neutrino mass with a sensitivity of $0.2\textrm{ eV/c}^2$ (90$\%$ C.L.) by precisely measuring the endpoint region of the tritium $\beta$-decay spectrum. It uses a tandem of electrostatic spectrometers working as MAC-E (magnetic adiabatic collimation combined with an electrostatic) filters. In the space between the pre-spectrometer and the main spectrometer, an unavoidable Penning trap is created when the superconducting magnet between the two spectrometers, biased at their respective nominal potentials, is energized. The electrons accumulated in this trap can lead to discharges, which create additional background electrons and endanger the spectrometer and detector section downstream. To counteract this problem, "electron catchers" were installed in the beamline inside the magnet bore between the two spectrometers. These catchers can be moved across the magnetic-flux tube and intercept on a sub-ms time scale the stored electrons along their magnetron motion paths. In this paper, we report on the design and the successful commissioning of the electron catchers and present results on their efficiency in reducing the experimental background., Comment: - 12 pages, 14 figures, LaTeX; typos corrected, references added; precised a few arguments, added additional discussions, results unchanged

Published
2019
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3. An improved upper limit on the neutrino mass from a direct kinematic method by KATRIN

Author

Aker, M., Altenmüller, K., Arenz, M., Babutzka, M., Barrett, J., Bauer, S., Beck, M., Beglarian, A., Behrens, J., Bergmann, T., Besserer, U., Blaum, K., Block, F., Bobien, S., Bokeloh, K., Bonn, J., Bornschein, B., Bornschein, L., Bouquet, H., Brunst, T., Caldwell, T. S., La Cascio, L., Chilingaryan, S., Choi, W., Corona, T. J., Debowski, K., Deffert, M., Descher, M., Doe, P. J., Dragoun, O., Drexlin, G., Dunmore, J. A., Dyba, S., Edzards, F., Eisenblätter, L., Eitel, K., Ellinger, E., Engel, R., Enomoto, S., Erhard, M., Eversheim, D., Fedkevych, M., Felden, A., Fischer, S., Flatt, B., Formaggio, J. A., Fränkle, F. M., Franklin, G. B., Frankrone, H., Friedel, F., Fuchs, D., Fulst, A., Furse, D., Gauda, K., Gemmeke, H., Gil, W., Glück, F., Görhardt, S., Groh, S., Grohmann, S., Grössle, R., Gumbsheimer, R., Minh, M. Ha, Hackenjos, M., Hannen, V., Harms, F., Hartmann, J., Haußmann, N., Heizmann, F., Helbing, K., Hickford, S., Hilk, D., Hillen, B., Hillesheimer, D., Hinz, D., Höhn, T., Holzapfel, B., Holzmann, S., Houdy, T., Howe, M. A., Huber, A., Jansen, A., Kaboth, A., Karl, C., Kazachenko, O., Kellerer, J., Kernert, N., Kippenbrock, L., Kleesiek, M., Klein, M., Köhler, C., Köllenberger, L., Kopmann, A., Korzeczek, M., Kosmider, A., Kovalí, A., Krasch, B., Kraus, M., Krause, H., Kuckert, L., Kuffner, B., Kunka, N., Lasserre, T., Le, T. L., Lebeda, O., Leber, M., Lehnert, B., Letnev, J., Leven, F., Lichter, S., Lobashev, V. M., Lokhov, A., Machatschek, M., Malcherek, E., Müller, K., Mark, M., Marsteller, A., Martin, E. L., Melzer, C., Menshikov, A., Mertens, S., Minter, L. I., Mirz, S., Monreal, B., Guzman, P. I. Morales, Naumann, U., Ndeke, W., Neumann, H., Niemes, S., Noe, M., Oblath, N. S., Ortjohann, H. -W., Osipowicz, A., Ostrick, B., Otten, E., Parno, D. S., Phillips II, D. G., Plischke, P., Pollithy, A., Poon, A. W. P., Pouryamout, J., Prall, M., Priester, F., Röllig, M., Röttele, C., Ranitzsch, P. C. -O., Rest, O., Rinderspacher, R., Robertson, R. G. H., Rodenbeck, C., Rohr, P., Roll, Ch., Rupp, S., Rysavy, M., Sack, R., Saenz, A., Schäfer, P., Schimpf, L., Schlösser, K., Schlösser, M., Schlüter, L., Schön, H., Schönung, K., Schrank, M., Schulz, B., Schwarz, J., Seitz-Moskaliuk, H., Seller, W., Sibille, V., Siegmann, D., Skasyrskaya, A., Slezak, M., Spalek, A., Spanier, F., Steidl, M., Steinbrink, N., Sturm, M., Suesser, M., Sun, M., Tcherniakhovski, D., Telle, H. H., Thümmler, T., Thorne, L. A., Titov, N., Tkachev, I., Trost, N., Urban, K., Venos, D., Valerius, K., VanDevender, B. A., Vianden, R., Hernandez, A. P. Vizcaya, Wall, B. L., Wüstling, S., Weber, M., Weinheimer, C., Weiss, C., Welte, S., Wendel, J., Wierman, K. J., Wilkerson, J. F., Wolf, J., Xu, W., Yen, Y. -R., Zacher, M., Zadorozhny, S., Zboril, M., and Zeller, G.

Subjects
High Energy Physics - Experiment, Astrophysics - Cosmology and Nongalactic Astrophysics, Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract

We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic endpoint at 18.57 keV gives an effective neutrino mass square value of $(-1.0^{+0.9}_{-1.1})$ eV$^2$. From this we derive an upper limit of 1.1 eV (90$\%$ confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of two and provides model-independent input to cosmological studies of structure formation.

Published
2019
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4. First operation of the KATRIN experiment with tritium

Author

Aker, M., Altenmüller, K., Arenz, M., Baek, W. -J., Barrett, J., Beglarian, A., Behrens, J., Berlev, A., Besserer, U., Blaum, K., Block, F., Bobien, S., Bornschein, B., Bornschein, L., Bouquet, H., Brunst, T., Caldwell, T. S., Chilingaryan, S., Choi, W., Debowski, K., Deffert, M., Descher, M., Barrero, D. Díaz, Doe, P. J., Dragoun, O., Drexlin, G., Dyba, S., Edzards, F., Eitel, K., Ellinger, E., Engel, R., Enomoto, S., Eversheim, D., Fedkevych, M., Felden, A., Formaggio, J. A., Fränkle, F. M., Franklin, G. B., Frankrone, H., Friedel, F., Fuchs, D., Fulst, A., Gauda, K., Gil, W., Glück, F., Grohmann, S., Grössle, R., Gumbsheimer, R., Hackenjos, M., Hannen, V., Hartmann, J., Haußmann, N., Minh, M. Ha, Heizmann, F., Heizmann, J., Helbing, K., Hickford, S., Hillesheimer, D., Hinz, D., Höhn, T., Holzapfel, B., Holzmann, S., Houdy, T., Howe, M. A., Huber, A., Jansen, A., Karl, C., Kellerer, J., Kernert, N., Kippenbrock, L., Kleesiek, M., Klein, M., Köhler, C., Köllenberger, L., Kopmann, A., Korzeczek, M., Kovalík, A., Krasch, B., Krause, H., Kuffner, B., Kunka, N., Lasserre, T., La Cascio, L., Lebeda, O., Lebert, M., Lehnert, B., Letnev, J., Leven, F., Le, T. L., Lichter, S., Lokhov, A., Machatschek, M., Malcherek, E., Mark, M., Marsteller, A., Martin, E. L., Megas, F., Melzer, C., Menshikov, A., Mertens, S., Meier, M., Mirz, S., Monreal, B., Guzmán, P. I. Morales, Müller, K., Naumann, U., Neumann, H., Niemes, S., Noe, M., Off, A., Ortjohann, H. -W., Osipowicz, A., Otten, E., Parno, D. S., Pollithy, A., Poon, A. W. P., Poyato, J. M. L., Priester, F., Ranitzsch, P. C. -O., Rest, O., Rinderspacher, R., Robertson, R. G. H., Rodenbeck, C., Rohr, P., Röllig, M., Röttele, C., Ryšavý, M., Sack, R., Saenz, A., Schäfer, P., Schimpf, L., Schlösser, K., Schlösser, M., Schlüter, L., Schrank, M., Schulz, B., Seitz-Moskaliuk, H., Seller, W., Sibille, V., Siegmann, D., Slezák, M., Spanier, F., Steidl, M., Steven, M., Sturm, M., Suesser, M., Sun, M., Tcherniakhovski, D., Telle, H. H., Thorne, L. A., Thümmler, T., Titov, N., Tkachev, I., Trost, N., Urban, K., Valerius, K., Vénos, D., Vianden, R., Hernández, A. P. Vizcaya, Weber, M., Weinheimer, C., Weiss, C., Welte, S., Wendel, J., Wilkerson, J. F., Wolf, J., Wüstling, S., Xu, W., Yen, Y. -R., Zadorozhny, S., and Zeller, G.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Experiment, Nuclear Experiment
Abstract

The determination of the neutrino mass is one of the major challenges in astroparticle physics today. Direct neutrino mass experiments, based solely on the kinematics of beta-decay, provide a largely model-independent probe to the neutrino mass scale. The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to directly measure the effective electron antineutrino mass with a sensitivity of 0.2 eV 90% CL. In this work we report on the first operation of KATRIN with tritium which took place in 2018. During this commissioning phase of the tritium circulation system, excellent agreement of the theoretical prediction with the recorded spectra was found and stable conditions over a time period of 13 days could be established. These results are an essential prerequisite for the subsequent neutrino mass measurements with KATRIN in 2019.

Published
2019
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5. Suppression of Penning discharges between the KATRIN spectrometers

Author

Aker, M, Altenmüller, K, Beglarian, A, Behrens, J, Berlev, A, Besserer, U, Blaum, K, Block, F, Bobien, S, Bornschein, B, Bornschein, L, Bouquet, H, Brunst, T, Caldwell, TS, Chilingaryan, S, Choi, W, Debowski, K, Deffert, M, Descher, M, Díaz Barrero, D, Doe, PJ, Dragoun, O, Drexlin, G, Dyba, S, Eitel, K, Ellinger, E, Engel, R, Enomoto, S, Eversheim, D, Fedkevych, M, Felden, A, Formaggio, JA, Fränkle, F, Franklin, GB, Frankrone, H, Friedel, F, Fulst, A, Gauda, K, Gil, W, Glück, F, Grohmann, S, Grössle, R, Gumbsheimer, R, Hackenjos, M, Hannen, V, Hartmann, J, Haußmann, N, Heizmann, F, Heizmann, J, Helbing, K, Hickford, S, Hillesheimer, D, Hinz, D, Höhn, T, Holzapfel, B, Holzmann, S, Houdy, T, Jansen, A, Karl, C, Kellerer, J, Kernert, N, Kippenbrock, L, Klein, M, Köhler, C, Köllenberger, L, Kopmann, A, Korzeczek, M, Kovalík, A, Krasch, B, Krause, H, Kuffner, B, Kunka, N, Lasserre, T, La Cascio, L, Lebeda, O, Lehnert, B, Letnev, J, Leven, F, Le, TL, Lichter, S, Lokhov, A, Machatschek, M, Malcherek, E, Marsteller, A, Martin, EL, Melzer, C, Menshikov, A, Mertens, S, Mirz, S, Monreal, B, Müller, K, Naumann, U, Neumann, H, Niemes, S, Noe, M, Ortjohann, HW, Osipowicz, A, Otten, E, Parno, DS, and Pollithy, A

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

The KArlsruhe TRItium Neutrino experiment (KATRIN) aims to determine the effective electron (anti)-neutrino mass with a sensitivity of 0.2eV/c2 by precisely measuring the endpoint region of the tritium β-decay spectrum. It uses a tandem of electrostatic spectrometers working as magnetic adiabatic collimation combined with an electrostatic (MAC-E) filters. In the space between the pre-spectrometer and the main spectrometer, creating a Penning trap is unavoidable when the superconducting magnet between the two spectrometers, biased at their respective nominal potentials, is energized. The electrons accumulated in this trap can lead to discharges, which create additional background electrons and endanger the spectrometer and detector section downstream. To counteract this problem, “electron catchers” were installed in the beamline inside the magnet bore between the two spectrometers. These catchers can be moved across the magnetic-flux tube and intercept on a sub-ms time scale the stored electrons along their magnetron motion paths. In this paper, we report on the design and the successful commissioning of the electron catchers and present results on their efficiency in reducing the experimental background.

Published
2020

6. First operation of the KATRIN experiment with tritium

Author

Aker, M, Altenmüller, K, Arenz, M, Baek, WJ, Barrett, J, Beglarian, A, Behrens, J, Berlev, A, Besserer, U, Blaum, K, Block, F, Bobien, S, Bornschein, B, Bornschein, L, Bouquet, H, Brunst, T, Caldwell, TS, Chilingaryan, S, Choi, W, Debowski, K, Deffert, M, Descher, M, Díaz Barrero, D, Doe, PJ, Dragoun, O, Drexlin, G, Dyba, S, Edzards, F, Eitel, K, Ellinger, E, Engel, R, Enomoto, S, Eversheim, D, Fedkevych, M, Felden, A, Formaggio, JA, Fränkle, FM, Franklin, GB, Frankrone, H, Friedel, F, Fuchs, D, Fulst, A, Gauda, K, Gil, W, Glück, F, Grohmann, S, Grössle, R, Gumbsheimer, R, Hackenjos, M, Hannen, V, Hartmann, J, Haußmann, N, Ha-Minh, M, Heizmann, F, Heizmann, J, Helbing, K, Hickford, S, Hillesheimer, D, Hinz, D, Höhn, T, Holzapfel, B, Holzmann, S, Houdy, T, Howe, MA, Huber, A, Jansen, A, Karl, C, Kellerer, J, Kernert, N, Kippenbrock, L, Klein, M, Köhler, C, Köllenberger, L, Kopmann, A, Korzeczek, M, Kovalík, A, Krasch, B, Krause, H, Kuffner, B, Kunka, N, Lasserre, T, La Cascio, L, Lebeda, O, Lebert, M, Lehnert, B, Letnev, J, Leven, F, Le, TL, Lichter, S, Lokhov, A, Machatschek, M, Malcherek, E, Mark, M, Marsteller, A, Martin, EL, Megas, F, Melzer, C, Menshikov, A, Mertens, S, and Meier, M

Subjects
Nuclear & Particles Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

The determination of the neutrino mass is one of the major challenges in astroparticle physics today. Direct neutrino mass experiments, based solely on the kinematics of β -decay, provide a largely model-independent probe to the neutrino mass scale. The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to directly measure the effective electron antineutrino mass with a sensitivity of 0.2eV (90 % CL). In this work we report on the first operation of KATRIN with tritium which took place in 2018. During this commissioning phase of the tritium circulation system, excellent agreement of the theoretical prediction with the recorded spectra was found and stable conditions over a time period of 13 days could be established. These results are an essential prerequisite for the subsequent neutrino mass measurements with KATRIN in 2019.

Published
2020

7. Development of a silicon drift detector array to search for keV-scale sterile neutrinos with the KATRIN experiment.

Author

Siegmann, D, Edzards, F, Bruch, C, Biassoni, M, Carminati, M, Descher, M, Fiorini, C, Forstner, C, Gavin, A, Gugiatti, M, Hiller, R, Hinz, D, Houdy, T, Huber, A, King, P, Lechner, P, Lichter, S, Mießner, D, Nava, A, and Onillon, A

Subjects
STERILE neutrinos, SILICON detectors, NEUTRINOS, FOCAL plane arrays sensors, NEUTRINO detectors, NEUTRINO mass, DARK matter
Abstract

Sterile neutrinos in the keV mass range present a viable candidate for dark matter. They can be detected through single β -decay, where they cause small spectral distortions. The Karlsruhe Tritium Neutrino (KATRIN) experiment aims to search for keV-scale sterile neutrinos with high sensitivity. To achieve this, the KATRIN beamline will be equipped with a novel multi-pixel silicon drift detector focal plane array named TRISTAN. In this study, we present the performance of a TRISTAN detector module, a component of the eventual 9-module system. Our investigation encompasses spectroscopic aspects such as noise performance, energy resolution, linearity, and stability. [ABSTRACT FROM AUTHOR]

Published
2024
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8. Howard Beach Youth: A Study of Racial and Ethnic Attitudes.

Author

Center for Media and Public Affairs, Washington, DC., Lichter, Linda S., and Lichter, S. Robert

Abstract

This assessment of the climate of racial and ethnic attitudes in Howard Beach (New York) was conducted at John Adams High School, the public school attended by the greatest number of high school children in the Howard Beach community. The survey of 1,217 students was administered in December, 1986, several weeks before the incident in which a number of Blacks were beaten and one died in Howard Beach. Results of the survey revealed a significant amount of racial and ethnic tolerance as well as tensions. Large majorities of all White groups reported that neither they nor their parents discouraged contacts with non-Whites. While students report a high perception of tolerance in their home environment, in school many students perceived the existence of racial and ethnic problems. The schools' three largest minority groups--Italians, Blacks, and Hispanics--elicited the highest rates of negative stereotyping. Findings demonstrated the complexity of prejudice. There was no consistent pattern of racial cleavage. (PS)

Published
1987

9. Does Hollywood Hate Business or Money?

Author

Lichter, S. Robert

Abstract

Uses content analysis of television characters in all occupations across 30 seasons to test the argument that television entertainment depicts business negatively. Reaffirms that television stigmatizes the occupation of business, independently of economic factors. Notes that these results pose a challenge to mass communications theory that interprets popular culture as a source of social control. (SR)

Published
1997

18. Neutral tritium gas reduction in the KATRIN differential pumping sections

Author

KATRIN Collaboration, Marsteller, A., Bornschein, B., Bornschein, L., Drexlin, G., Friedel, F., Gehring, R., Grohmann, S., Gumbsheimer, R., Hackenjos, M., Jansen, A., Kosmider, A., LaCascio, L., Lichter, S., Müller, K., Priester, F., Rinderspacher, R., Röllig, M., Röttele, C., Sharipov, F., Sturm, M., Welte, S., and Wolf, J.

Subjects
Technology, Materials science, Physics - Instrumentation and Detectors, Orders of magnitude (temperature), Physics::Instrumentation and Detectors, FOS: Physical sciences, 02 engineering and technology, Superconducting magnet, Tritium, 01 natural sciences, Nuclear physics, TPMC simulation, 0103 physical sciences, KATRIN experiment, Nuclear Experiment (nucl-ex), Instrumentation and Methods for Astrophysics (astro-ph.IM), Instrumentation, Nuclear Experiment, 010302 applied physics, Tritium illumination, Vacuum measurement, Spectrometer, Pumping speed, Instrumentation and Detectors (physics.ins-det), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Surfaces, Coatings and Films, Gas flow, Beamline, Physics::Accelerator Physics, Neutrino, 0210 nano-technology, Astrophysics - Instrumentation and Methods for Astrophysics, ddc:600, KATRIN
Abstract

The KArlsruhe TRItium Neutrino experiment (KATRIN) aims to measure the effective electron anti-neutrino mass with an unprecedented sensitivity of $0.2\,\mathrm{eV}/\mathrm{c}^2$, using $\beta$-electrons from tritium decay. The electrons are guided magnetically by a system of superconducting magnets through a vacuum beamline from the windowless gaseous tritium source through differential and cryogenic pumping sections to a high resolution spectrometer and a segmented silicon pin detector. At the same time tritium gas has to be prevented from entering the spectrometer. Therefore, the pumping sections have to reduce the tritium flow by more than 14 orders of magnitude. This paper describes the measurement of the reduction factor of the differential pumping section performed with high purity tritium gas during the first measurement campaigns of the KATRIN experiment. The reduction factor results are compared with previously performed simulations, as well as the stringent requirements of the KATRIN experiment., Comment: 19 pages, 4 figures, submitted to Vacuum

Published
2021
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19. Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN

Author

KATRIN Collaboration, Aker, M., Altenmüller, K., Arenz, M., Babutzka, M., Barrett, J., Bauer, S., Beck, M., Beglarian, A., Behrens, J., Bergmann, T., Besserer, U., Blaum, K., Block, F., Bobien, S., Bokeloh, K., Bonn, J., Bornschein, B., Bornschein, L., Bouquet, H., Brunst, T., Caldwell, T. S., La Cascio, L., Chilingaryan, S., Choi, W., Corona, T. J., Debowski, K., Deffert, M., Descher, M., Doe, P. J., Dragoun, O., Drexlin, G., Dunmore, J. A., Dyba, S., Edzards, F., Eisenblätter, L., Eitel, K., Ellinger, E., Engel, R., Enomoto, S., Erhard, M., Eversheim, D., Fedkevych, M., Felden, A., Fischer, S., Flatt, B., Formaggio, J. A., Fränkle, F. M., Franklin, G. B., Frankrone, H., Friedel, F., Fuchs, D., Fulst, A., Furse, D., Gauda, K., Gemmeke, H., Gil, W., Glück, F., Görhardt, S., Groh, S., Grohmann, S., Grössle, R., Gumbsheimer, R., Ha Minh, M., Hackenjos, M., Hannen, V., Harms, F., Hartmann, J., Haußmann, N., Heizmann, F., Helbing, K., Hickford, S., Hilk, D., Hillen, B., Hillesheimer, D., Hinz, D., Höhn, T., Holzapfel, B., Holzmann, S., Houdy, T., Howe, M. A., Huber, A., James, T. M., Jansen, A., Kaboth, A., Karl, C., Kazachenko, O., Kellerer, J., Kernert, N., Kippenbrock, L., Kleesiek, M., Klein, M., Köhler, C., Köllenberger, L., Kopmann, A., Korzeczek, M., Kosmider, A., Kovalík, A., Krasch, B., Kraus, M., Krause, H., Kuckert, L., Kuffner, B., Kunka, N., Lasserre, T., Le, T. L., Lebeda, O., Leber, M., Lehnert, B., Letnev, J., Leven, F., Lichter, S., Lobashev, V. M., Lokhov, A., Machatschek, M., Malcherek, E., Müller, K., Mark, M., Marsteller, A., Martin, E. L., Melzer, C., Menshikov, A., Mertens, S., Minter, L. I., Mirz, S., Monreal, B., Morales Guzmán, P. I., Naumann, U., Ndeke, W., Neumann, H., Niemes, S., Noe, M., Oblath, N. S., Ortjohann, H.-W., Osipowicz, A., Ostrick, B., Otten, E., Parno, D. S., Phillips, D. G., Plischke, P., Pollithy, A., Poon, A. W. P., Pouryamout, J., Prall, M., Priester, F., Röllig, M., Röttele, C., Ranitzsch, P. C.-O., Rest, O., Rinderspacher, R., Robertson, R. G. H., Rodenbeck, C., Rohr, P., Roll, Ch., Rupp, S., Ryšavý, M., Sack, R., Saenz, A., Schäfer, P., Schimpf, L., Schlösser, K., Schlösser, M., Schlüter, L., Schön, H., Schönung, K., Schrank, M., Schulz, B., Schwarz, J., Seitz-Moskaliuk, H., Seller, W., Sibille, V., Siegmann, D., Skasyrskaya, A., Slezák, M., Špalek, A., Spanier, F., Steidl, M., Steinbrink, N., Sturm, M., Suesser, M., Sun, M., Tcherniakhovski, D., Telle, H. H., Thümmler, T., Thorne, L. A., Titov, N., Tkachev, I., Trost, N., Urban, K., Vénos, D., Valerius, K., VanDevender, B. A., Vianden, R., Vizcaya Hernández, A. P., Wall, B. L., Wüstling, S., Weber, M., Weinheimer, C., Weiss, C., Welte, S., Wendel, J., Wierman, K. J., Wilkerson, J. F., Wolf, J., Xu, W., Yen, Y.-R., Zacher, M., Zadorozhny, S., Zbořil, M., Zeller, G., AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, KATRIN, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and KATRIN Collaboration

Subjects
Semileptonic decay, Physics - Instrumentation and Detectors, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Physics::Instrumentation and Detectors, FOS: Physical sciences, General Physics and Astronomy, Kinematics, Electron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], KATRIN, 01 natural sciences, 7. Clean energy, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), mass: scale, neutrino: mass: measured, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], ddc:530, S066MAE, Sensitivity (control systems), Limit (mathematics), structure, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, tritium, formation, S066M2E, Instrumentation and Detectors (physics.ins-det), semileptonic decay, sensitivity, ddc, kinematics, Elementary Particles and Fields, electron: energy spectrum, High Energy Physics::Experiment, Präzisionsexperimente - Abteilung Blaum, Neutrino, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Energy (signal processing), Astrophysics - Cosmology and Nongalactic Astrophysics, experimental results
Abstract

We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (−1.0−1.1+0.9) eV2. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation.

Published
2019

20. Does Hollywood hate business or money?

Author

Lichter, S. Robert, Lichter, Linda S., and Amundson, Daniel

Subjects
Characters and characteristics -- Analysis, Businessmen -- Portrayals, Television programs -- Analysis, Sociology and social work
Abstract

A content analysis of TV characters in all occupations across 30 seasons was conducted to test the argument that TV depicts wealth, rather than business, negatively. Results reaffirm that TV negatively portrays business characters, with the business environment treated as one of greed and corruption. Business characters in primetime fictional series showed significantly more negative behavior than characters in other occupations, independent of economic status. These findings challenge mass communications theory stating that popular culture is a source of social control.

Published
1997

23. Government in and out of the news: a groundbreaking study shows that there is less news about the federal government in the national media than there used to be, and that what news there is tends to be negative and judgmental. How is all this affecting our view of government?

Author

Lichter, S. Robert and McGinnis, Patricia

Subjects
Mass media industry -- Management, Administrative agencies -- Management -- Media coverage, Municipal services -- Management, Government, Company business management, Management, Media coverage
Abstract

The past 20 years have been marked by dramatic changes in the political environment. When Ronald Reagan became president in 1981, American hostages were being released after their lengthy captivity [...]

Published
2003

24. Social science and ideology: a reply to Prindle, Endersby, and Gans

Author

Rothman, Stanley and Lichter, S. Robert

Subjects
Social science research -- Evaluation, Political science, Social sciences, Sociology and social work
Abstract

Criticism of a scholarly work can only be acceptable if it concentrates on arguments and evidence, not on personal beliefs or motivations. Critics of the study on Hollywood liberalism should realize that the proponents did not extol the contributions of Jewish Americans in Hollywood but merely noted the religious backgrounds of respondents as part of their demographic profiles. Moreover, empirical methods are acceptable methods in scientific inquiry and the validity of findings based on such methods cannot be questioned.

Published
1994

25. Scientific Opinion on Climate Change across Two Decades

Author

Stephen J. Farnsworth, Justin Rolfe-Redding, and Robert Lichter S

Subjects
Data collection, Geography, Environmental change, Meteorology, Scientific progress, Global warming, Regional science, Climate change, Climate model, Causation, Sampling frame
Abstract

This study examines a unique dataset of polling results from two comparable surveys, which asked the same questions of US. atmospheric and ocean scientists in 1991 and 2007. Using this measure of change in scientific opinion over time, the data shed light on the evolution of a consensus over a critical and dynamic 16-year period in the history of climate science. In 1991, considerable uncertainty and disagreement existed among climate scientists. With the passage of time and additional research, by 2007 a clear consensus had emerged, along with increased confidence in the opinions expressed. This is the path that scientific progress is expected to take, and it argues against charges that the climate science community rushed to judgment or engaged in groupthink on global warming. The period 1991 to 2007 was a time of considerable expansion in the scientific community’s conclusions about global warming, as reflected in the reports of bodies such as the U.N.’s Intergovernmental Panel on Climate. In 1990, the IPCC issued its First Assessment Report [1,2], expressing confidence that global warming was occurring, but noting uncertainty on the anthropogenic origin of observed warming. By 2007 (just prior to data collection in the survey reported here), the initial sections of the Fourth IPCC assessment2 were released, expressing “very high confidence” that human activity was causing global warming (p. 3), and describing evidence of warming as “unequivocal” (p. 5). In addition to the synthesis reports, results of surveys of scientists can offer another measure of the state of scientific opinion. In 1990, an international sample of “global environmental change” scientists showed strong support for action to address climate change, but lower scientific certainty-65% thought there was a more than 50% chance of 2 degree Celsius warming over the subsequent 100 years [3]. A further survey indicated a divide among scientists over the existence of anthropogenic warming [4]. A 1996 international survey of climate scientists and meteorologists indicated fairly high certainty in long-range warming sufficient to justify policy action [5]. The scientists expressed limited trust, however, in climate models and uncertainty on the specific impacts of climate change. Between 2006 and 2008, three surveys of scientists with different sampling frames all provided a more recent picture of scientific opinion [6–8]. They demonstrated broad confidence in the methods, and consensus on the findings of climate science, in areas that are prerequisites to basic agreement on human causation. For example, 90% of one sample concurred that temperatures have risen over pre-industrial levels [9]. While confidence in scientific understanding of certain elements of the climate system was high (e.g., the role of albedo), lingering uncertainty remained on some of the predictions and other fine points of the workings of the climate system (e.g., the role of cloud cover [6]). These surveys, however, fail to provide a rigorous longitudinal perspective. Each employed its own survey frame, question wording, and sampling and administration methodology. While broad trends may be discernable from examining such disparate datasets, and worthy efforts have been conducted in this regard [10-13], an applesto- apples comparison would provide a far more precise measure of changes in scientific opinion. The current study addresses the need for longitudinal data on scientific opinion about climate change by comparing the results of two surveys of US atmospheric and ocean scientists-one administered in 1991 and one in 2007-designed with similar methodological profiles and virtually identical question wordings, allowing for superior comparison of the survey results from these two points in time. This study also examines a richer array of topics than prior longitudinal analyses.

Published
2015

26. The nightly news nightmare : media coverage of U.S. presidential elections, 1988-2008.

Author

Farnsworth, Stephen J. and Lichter, S. Robert

Subjects
Political campaigns -- United States -- Press coverage -- United States, Presidents -- United States -- Election -- History -- 20th century, Press and politics -- United States, Television broadcasting of news -- United States
Abstract

Summary: The Nightly News Nightmare, Third Edition, examines news coverage of presidential nomination and election campaigns from 1988 to 2008. The book focuses on changes in the amount, tone, and focus of news coverage in these different electoral contexts. In addition to network news, the authors examine online news, cable television, talk radio, candidate campaign discourse in these election years. Farnsworth and Lichter find that the news media, despite the wide variety of outlets, have consistent problems in terms of fairness and focus on substantive matters rather than the horse-race reporting of the latest polls. In addition to the extensive discussion of the 2008 campaign, the third edition offers far more discussion and evidence regarding the use of alternative media, including online content, in the most recent presidential election. The authors conclude that online news had many of the same problems found in mainstream news coverage.

Published
2011

27. How liberal are bureaucrats?

Author

Rothman, Stanley and Lichter, S. Robert

Subjects
Bureaucracy -- Research, Public employees, Business, Government, Law
Published
1983

29. Commentary; The Press Spins Self-Serving Myths

Author

Lichter, S. Robert and Butterworth, Trevor

Subjects
World War II, 1939-1945 -- Media coverage, Korean War, 1950-1953 -- Media coverage, Vietnam War, 1959-1975 -- Media coverage, War -- Media coverage, General interest, News, opinion and commentary
Published
2001

33. What, us biased? Some doubts

Author

Lichter, S. Robert

Subjects
Elections -- Media coverage, Mass media criticism -- Political aspects, Journalism -- Objectivity
Published
1992

35. Good intentions lost in negatives

Author

Lichter, S. Robert

Subjects
Presidential candidates -- Media coverage, Political campaigns -- Media coverage, Press and politics -- Analysis
Published
1992

36. Prime time goes politically correct

Author

Lichter, S. Robert

Subjects
Right and left (Political science) -- Analysis, Television programs -- Political aspects
Published
1991

38. Iraq, 9/11, and the Mediated Presidency of George W. Bush.

Author

Farnsworth, Stephen J. and Lichter, S. Robert

Subjects
MASS media & politics, PRESIDENTIAL administrations, SEPTEMBER 11 Terrorist Attacks, 2001, IRAQ War, 2003-2011
Abstract

The article focuses on the key media management schemes used during the administration of U.S. President George W. Bush. It states that the White House Office enjoyed comparatively positive news coverage in the succeeding months after the September 11, 2001 aftermath and during the combat phase of the Iraq war in 2003. It notes that all the presidents appear to have better press once a military action is afoot and news coverage is negative when the president does not serve as commander in chief.

Published
2008

41. Personality, Ideology and World View: A Comparison of Media and Business Elites.

Author

Rothman, Stanley and Lichter, S. Robert

Subjects
PERSONALITY, IDEOLOGY, ECONOMIC elites, MASS media, CAPITALIST societies, INTELLECTUALS, QUESTIONNAIRES, THEMATIC Apperception Test, JOURNALISTS, BUSINESSMEN
Abstract

From rather different perspectives some conservative and radical intellectuals have argued that new strata (a 'new class') have emerged in advanced industrial capitalist society whose values differ from those more closely tied to the central institutions of such societies. Both conservative and radical intellectuals argue that prominent among these new strata are those individuals associated with the creation and dissemination of culture. To test these hypotheses we administered a questionnaire to a stratified random sample of media personnel from the leading media outlets in the country, and to a stratified random sample of businessmen drawn from major companies on various Fortune lists. Our return rate was 74 per cent and 95 per cent respectively. In addition to questions on background, outlook and ideology, our questionnaire contained a series of Thematic Apperception Test pictures (TAT) scored blind, according to criteria established by David McClelland and associates. We found that media personnel come from more privileged backgrounds than businessmen, and are considerably more liberal and cosmopolitan. We found, too, that the manner in which both journalists and businessmen interpret "reality" is consonant with their expressed ideological views. Finally, we found that businessmen outscore journalists on the Need for Achievement, while journalists outscore businessmen on the Need for Power, Fear of Power and Narcissism. The broader implications of these findings are discussed in the final section of the article. [ABSTRACT FROM AUTHOR]

Published
1985
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43. Influence of vane sweep on rotor-stator interaction noise.

Author

Lichter, S. H., Balsa, T. F., Lamb, G. L., Brendel, K., Envia, Edmane., Lichter, S. H., Balsa, T. F., Lamb, G. L., Brendel, K., and Envia, Edmane.

Abstract

In this dissertation the influence of vane sweep on rotor-stator interaction noise is investigated. In an analytical approach, the interaction of a convected gust, representing the rotor viscous wake, with a cascade of finite span swept airfoils, representing the stator, is analyzed. The analysis is based on the solution of the exact linearized equations of motion. High-frequency convected gusts for which noise generation is concentrated near the leading edge of the airfoils are considered. In a preliminary study, the problem of an isolated finite span swept airfoil interacting with a convected gust is analyzed. Using Fourier transform methods and the Wiener-Hopf technique, an approximate solution for this problem is developed. Closed form expressions for the acoustic farfield are obtained and used in a parametric study to assess the effect of airfoil sweep on noise generation. Results indicate that sweep can substantially reduce the farfield noise levels for a single airfoil. Utilizing the single airfoil model, an approximate solution to the problem of noise radiation from a cascade of finite span swept airfoils interacting with a convected gust is derived. Only upstream radiated noise is considered. Neglecting the weak coupling between the adjacent leading edges at high frequencies, the cascade solution is constructed as a superposition of acoustic farfields emanating from an infinite number of isolated airfoils. A parametric study of noise generated by gust-cascade interaction is then carried out to assess the effectiveness of vane sweep in reducing rotor-stator interaction noise. The results of the parametric study show that, over a fairly wide range of conditions, sweep is beneficial in reducing noise levels. One conclusion of particular importance is that rotor wake twist or circumferential lean substantially influences the effectiveness of vane sweep. The orientation of the vane sweep must be chosen to enhance the natural phase lag caused by wake lean, in whi

Published
1988

44. Viscous cross-waves: Stability and bifurcation.

Author

Lichter, S. H., Sears, W. R., McLaughlin, D. W., Chen, C. F., Kwok, Loong-Piu., Lichter, S. H., Sears, W. R., McLaughlin, D. W., Chen, C. F., and Kwok, Loong-Piu.

Abstract

In the first part of this thesis, the nonlinear Schrodinger equation for inviscid cross-waves near onset is found to be modified by viscous linear damping and detuning. The accompanying boundary condition at the wavemaker is also modified by damping from the wavemaker meniscus. The relative contributions of the free-surface, sidewalls, bottom, and wavemaker viscous boundary layers are computed. It is shown that viscous dissipation due to the wavemaker meniscus breaks the symmetry of the neutral curve. In the second part, existence and stability of steady solutions to the nonlinear Schrodinger equation are examined numerically. It is found that at forcing frequency above a critical value, f(c), only one solution exists. However, below f(c), multiple steady solutions, the number of which is determined, are possible. This multiplicity leads to hysteresis for f < f(c), in agreement with observation. A Hopf bifurcation of the steady solutions is found. This bifurcation is compared with the transition from unmodulated to periodically modulated cross-waves observed experimentally.

Published
1988

45. Cells in 3D matrices under interstitial flow: Effects of extracellular matrix alignment on cell shear stress and drag forces

Author

Pedersen, J. A., Lichter, S., and Swartz, M. A.

Subjects
Mechanobiology, Perfusion, Collagen, Computational fluid dynamics, Brinkman flow
Abstract

Interstitial flow is an important regulator of various cell behaviors both in vitro and in vivo, yet the forces that fluid flow imposes on cells embedded in a 3D extracellular matrix (ECM), and the effects of matrix architecture on those forces, are not well understood. Here, we demonstrate how fiber alignment can affect the shear and pressure forces on the cell and ECM. Using computational fluid dynamics simulations, we show that while the solutions of the Brinkman equation accurately estimate the average fluid shear stress and the drag forces on a cell within a 3D fibrous medium, the distribution of shear stress on the cellular surface as well as the peak shear stresses remain intimately related to the pericellular fiber architecture and cannot be estimated using bulk-averaged properties. We demonstrate that perpendicular fiber alignment of the ECM yields lower shear stress and pressure forces on the cells and higher stresses on the ECM, leading to decreased permeability, while parallel fiber alignment leads to higher stresses on cells and increased permeability, as compared to a cubic lattice arrangement. The Spielman-Goren permeability relationships for fibrous media agreed well with CFD simulations of flow with explicitly considered fibers. These results suggest that the experimentally observed active remodeling of ECM fibers by fibroblasts under interstitial flow to a perpendicular alignment could serve to decrease the shear and drag forces on the cell. © 2009 Elsevier Ltd. All rights reserved.

46. Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN

Author

Aker, M., Altenmüller, K., Arenz, M., Babutzka, M., Barrett, J., Bauer, S., Beck, M., Beglarian, A., Behrens, J., Bergmann, T., Besserer, U., Blaum, K., Block, F., Bobien, S., Bokeloh, K., Bonn, J., Bornschein, B., Bornschein, L., Bouquet, H., Brunst, T., Caldwell, T. S., La Cascio, L., Chilingaryan, S., Choi, W., Corona, T. J., Debowski, K., Deffert, M., Descher, M., Doe, P. J., Dragoun, O., Drexlin, G., Dunmore, J. A., Dyba, S., Edzards, F., Eisenblätter, L., Eitel, K., Ellinger, E., Engel, R., Enomoto, S., Erhard, M., Eversheim, D., Fedkevych, M., Felden, A., Fischer, S., Flatt, B., Formaggio, J. A., Fränkle, F. M., Franklin, G. B., Frankrone, H., Friedel, F., Fuchs, D., Fulst, A., Furse, D., Gauda, K., Gemmeke, H., Gil, W., Glück, F., Görhardt, S., Groh, S., Grohmann, S., Grössle, R., Gumbsheimer, R., Ha Minh, M., Hackenjos, M., Hannen, V., Harms, F., Hartmann, J., Haußmann, N., Heizmann, F., Helbing, K., Hickford, S., Hilk, D., Hillen, B., Hillesheimer, D., Hinz, D., Höhn, T., Holzapfel, B., Holzmann, S., Houdy, T., Howe, M. A., Huber, A., James, T. M., Jansen, A., Kaboth, A., Karl, C., Kazachenko, O., Kellerer, J., Kernert, N., Kippenbrock, L., Kleesiek, M., Klein, M., Köhler, C., Köllenberger, L., Kopmann, A., Korzeczek, M., Kosmider, A., Kovalík, A., Krasch, B., Kraus, M., Krause, H., Kuckert, L., Kuffner, B., Kunka, N., Lasserre, T., Le, T. L., Lebeda, O., Leber, M., Lehnert, B., Letnev, J., Leven, F., Lichter, S., Lobashev, V. M., Lokhov, A., Machatschek, M., Malcherek, E., Müller, K., Mark, M., Marsteller, A., Martin, E. L., Melzer, C., Menshikov, A., Mertens, S., Minter, L. I., Mirz, S., Monreal, B., Morales Guzmán, P. I., Naumann, U., Ndeke, W., Neumann, H., Niemes, S., Noe, M., Oblath, N. S., Ortjohann, H.-W., Osipowicz, A., Ostrick, B., Otten, E., Parno, D. S., Phillips, D. G., Plischke, P., Pollithy, A., Poon, A. W. P., Pouryamout, J., Prall, M., Priester, F., Röllig, M., Röttele, C., Ranitzsch, P. C.-O., Rest, O., Rinderspacher, R., Robertson, R. G. H., Rodenbeck, C., Rohr, P., Roll, Ch., Rupp, S., Ryšavý, M., Sack, R., Saenz, A., Schäfer, P., Schimpf, L., Schlösser, K., Schlösser, M., Schlüter, L., Schön, H., Schönung, K., Schrank, M., Schulz, B., Schwarz, J., Seitz-Moskaliuk, H., Seller, W., Sibille, V., Siegmann, D., Skasyrskaya, A., Slezák, M., Špalek, A., Spanier, F., Steidl, M., Steinbrink, N., Sturm, M., Suesser, M., Sun, M., Tcherniakhovski, D., Telle, H. H., Thümmler, T., Thorne, L. A., Titov, N., Tkachev, I., Trost, N., Urban, K., Vénos, D., Valerius, K., VanDevender, B. A., Vianden, R., Vizcaya Hernández, A. P., Wall, B. L., Wüstling, S., Weber, M., Weinheimer, C., Weiss, C., Welte, S., Wendel, J., Wierman, K. J., Wilkerson, J. F., Wolf, J., Xu, W., Yen, Y.-R., Zacher, M., Zadorozhny, S., Zbořil, M., and Zeller, G.

Subjects
Physics::Instrumentation and Detectors, High Energy Physics::Experiment, 7. Clean energy
Abstract

We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of $(−1.0^{+0.9}_{−1.1}) eV^2$. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation.

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