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35 results on '"K. S. Khaw"'

1. muCool: a next step towards efficient muon beam compression

Author

I. Belosevic, A. Antognini, Y. Bao, A. Eggenberger, M. Hildebrandt, R. Iwai, D. M. Kaplan, K. S. Khaw, K. Kirch, A. Knecht, A. Papa, C. Petitjean, T. J. Phillips, F. M. Piegsa, N. Ritjoho, A. Stoykov, D. Taqqu, and G. Wichmann

Subjects
Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract A novel device to compress the phase space of a muon beam by a factor of $$10^{10}$$ 1010 with a $$10^{-3}$$ 10-3 efficiency is under development. A surface muon beam is stopped in a helium gas target consisting of several compression stages, wherein strong electric and magnetic fields are applied. The spatial extent of the stopped muon swarm is decreased by means of these fields until muons with eV energy are extracted into vacuum through a small orifice. It was observed that a 20 cm long muon stop distribution can be compressed in the longitudinal direction to a sub-mm extent within $$2~\upmu \hbox {s}$$ 2μs . Additionally, a drift perpendicular to the magnetic field of the compressed low-energy muon swarm was successfully demonstrated, paving the way towards extraction from the gas and re-acceleration of the muons.

Published
2019
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2. Muon spinning its way to new physics

Author

Jing Shu, K. S. Khaw, and Liang Li

Subjects
Physics, Nuclear physics, Muon, Physics and Astronomy (miscellaneous), Physics beyond the Standard Model, Spinning
Published
2021

3. Measurement of the anomalous precession frequency of the muon in the Fermilab Muon <math><mi>g</mi><mo>−</mo><mn>2</mn></math> Experiment

Author

P. Bloom, P. Kammel, Timothy Chupp, C. Schlesier, P. Girotti, M. J. Lee, A. Nath, Frederick Gray, C. Gabbanini, D. Shemyakin, C. C. Polly, L. Cotrozzi, V. N. Duginov, G. Venanzoni, T. Stuttard, G. Lukicov, M. Iacovacci, H. E. Swanson, T. P. Gorringe, B. C.K. Casey, J. Grange, N. H. Tran, K. W. Hong, K. T. Pitts, R. T. Chislett, Fabrizio Marignetti, A. Lucà, Martin Fertl, E. Barlas-Yucel, J. George, A. Kuchibhotla, Dariush Hampai, T. Walton, D. Cauz, G. Sweetmore, J. Bono, I. R. Bailey, Dinko Pocanic, J. L. Holzbauer, Gavin Grant Hesketh, J. L. Ritchie, Alexander Keshavarzi, H. P. Binney, A. García, Manolis Kargiantoulakis, A. Basti, Barry King, B. MacCoy, M. Kiburg, David Rubin, Alexey Anisenkov, V. Tishchenko, Marin Karuza, H. Nguyen, P. Di Meo, Claudio Ferrari, N. Kinnaird, Liang Li, L. K. Gibbons, N. Raha, R. Chakraborty, D. Flay, R. N. Pilato, M. Incagli, M. Lancaster, Michael Syphers, S. Baeßler, T. J. V. Bowcock, J. LaBounty, G. M. Piacentino, D. Vasilkova, S. Park, A. Lusiani, T. Albahri, R. Madrak, Z. Hodge, Dominik Stöckinger, A. Chapelain, Brad Plaster, R. M. Carey, Dongdong Li, J. D. Crnkovic, D. W. Hertzog, Selcuk Haciomeroglu, J. P. Miller, Andrzej Wolski, Tabitha Halewood-leagas, Franco Bedeschi, B. L. Roberts, S. Grant, J. Fry, Kyoko Makino, J.B. Hempstead, S. Di Falco, K. S. Khaw, W. Turner, Z. Chu, A. T. Herrod, J. D. Price, T. Barrett, N. V. Khomutov, M. Farooq, P. Winter, J. Stapleton, R. Fatemi, D. Kawall, S. Charity, L. Santi, A. Schreckenberger, E. Valetov, B. Quinn, Yannis K. Semertzidis, B. Li, K. L. Giovanetti, A. E. Tewsley-Booth, S. Lee, Ran Hong, S. Leo, M. D. Galati, A.T. Fienberg, Sultan B. Dabagov, S. P. Chang, L. Kelton, G. Pauletta, Rachel Osofsky, G. Di Sciascio, S. Ganguly, D.A. Sweigart, Meghna Bhattacharya, Thomas Teubner, A. Gioiosa, S. Miozzi, B. Kiburg, J. Esquivel, A. Lorente Campos, David Kessler, E. Bottalico, M. Sorbara, Christopher Stoughton, J. Mott, Kayleigh Anne Thomson, Giovanni Cantatore, A. Fioretti, A. Anastasi, Wanwei Wu, Karie Badgley, S. Mastroianni, O. Kim, William Morse, L. Welty-Rieger, A. L. Lyon, A. Hibbert, A. Weisskopf, P. T. Debevec, W. Gohn, E. J. Ramberg, R. Di Stefano, E. Kraegeloh, Martin Berz, Z. Khechadoorian, S. Ramachandran, D. Stratakis, S. Corrodi, D. A. Tarazona, V. A. Baranov, J. Choi, F. Han, Nicholas A. Pohlman, M. Eads, I. Logashenko, N. A. Kuchinskiy, M. W. Smith, Y. I. Kim, A. Driutti, J. Kaspar, K. R. Labe, N. S. Froemming, E. Frlež, Albahri, T., Anastasi, A., Anisenkov, A., Badgley, K., Baeßler, S., Bailey, I., Baranov, V. A., Barlas-Yucel, E., Barrett, T., Basti, A., Bedeschi, F., Berz, M., Bhattacharya, M., Binney, H. P., Bloom, P., Bono, J., Bottalico, E., Bowcock, T., Cantatore, G., Carey, R. M., Casey, B. C. K., Cauz, D., Chakraborty, R., Chang, S. P., Chapelain, A., Charity, S., Chislett, R., Choi, J., Chu, Z., Chupp, T. E., Corrodi, S., Cotrozzi, L., Crnkovic, J. D., Dabagov, S., Debevec, P. T., Di Falco, S., Di Meo, P., Di Sciascio, G., Di Stefano, R., Driutti, A., Duginov, V. N., Eads, M., Esquivel, J., Farooq, M., Fatemi, R., Ferrari, C., Fertl, M., Fienberg, A. T., Fioretti, A., Flay, D., Frlež, E., Froemming, N. S., Fry, J., Gabbanini, C., Galati, M. D., Ganguly, S., Garcia, A., George, J., Gibbons, L. K., Gioiosa, A., Giovanetti, K. L., Girotti, P., Gohn, W., Gorringe, T., Grange, J., Grant, S., Gray, F., Haciomeroglu, S., Halewood-Leagas, T., Hampai, D., Han, F., Hempstead, J., Herrod, A. T., Hertzog, D. W., Hesketh, G., Hibbert, A., Hodge, Z., Holzbauer, J. L., Hong, K. W., Hong, R., Iacovacci, M., Incagli, M., Kammel, P., Kargiantoulakis, M., Karuza, M., Kaspar, J., Kawall, D., Kelton, L., Keshavarzi, A., Kessler, D., Khaw, K. S., Khechadoorian, Z., Khomutov, N. V., Kiburg, B., Kiburg, M., Kim, O., Kim, Y. I., King, B., Kinnaird, N., Kraegeloh, E., Kuchibhotla, A., Kuchinskiy, N. A., Labe, K. R., Labounty, J., Lancaster, M., Lee, M. J., Lee, S., Leo, S., Li, B., Li, D., Li, L., Logashenko, I., Lorente Campos, A., Lucà, A., Lukicov, G., Lusiani, A., Lyon, A. L., Maccoy, B., Madrak, R., Makino, K., Marignetti, F., Mastroianni, S., Miller, J. P., Miozzi, S., Morse, W. M., Mott, J., Nath, A., Nguyen, H., Osofsky, R., Park, S., Pauletta, G., Piacentino, G. M., Pilato, R. N., Pitts, K. T., Plaster, B., Počanić, D., Pohlman, N., Polly, C. C., Price, J., Quinn, B., Raha, N., Ramachandran, S., Ramberg, E., Ritchie, J. L., Roberts, B. L., Rubin, D. L., Santi, L., Schlesier, C., Schreckenberger, A., Semertzidis, Y. K., Shemyakin, D., Smith, M. W., Sorbara, M., Stöckinger, D., Stapleton, J., Stoughton, C., Stratakis, D., Stuttard, T., Swanson, H. E., Sweetmore, G., Sweigart, D. A., Syphers, M. J., Tarazona, D. A., Teubner, T., Tewsley-Booth, A. E., Thomson, K., Tishchenko, V., Tran, N. H., Turner, W., Valetov, E., Vasilkova, D., Venanzoni, G., Walton, T., Weisskopf, A., Welty-Rieger, L., Winter, P., Wolski, A., and Wu, W.

Subjects
Physics::Instrumentation and Detectors, Measure (physics), FOS: Physical sciences, 7. Clean energy, 01 natural sciences, Omega, High Energy Physics - Experiment, Nuclear physics, Nuclear Experiment, High Energy Physics - Experiment (hep-ex), muon, 0103 physical sciences, Fermilab, Nuclear Experiment (nucl-ex), 010306 general physics, Larmor precession, Physics, Muon, 010308 nuclear & particles physics, Settore FIS/01 - Fisica Sperimentale, anomalous magnetic moment, 3. Good health, Magnetic field, Physics::Accelerator Physics, High Energy Physics::Experiment, Storage ring, Fermi Gamma-ray Space Telescope
Abstract

The Muon g-2 Experiment at Fermi National Accelerator Laboratory (FNAL) has measured the muon anomalous precession frequency $\omega_a$ to an uncertainty of 434 parts per billion (ppb), statistical, and 56 ppb, systematic, with data collected in four storage ring configurations during its first physics run in 2018. When combined with a precision measurement of the magnetic field of the experiment's muon storage ring, the precession frequency measurement determines a muon magnetic anomaly of $a_{\mu}({\rm FNAL}) = 116\,592\,040(54) \times 10^{-11}$ (0.46 ppm). This article describes the multiple techniques employed in the reconstruction, analysis and fitting of the data to measure the precession frequency. It also presents the averaging of the results from the eleven separate determinations of \omega_a, and the systematic uncertainties on the result., Comment: 29 pages, 19 figures. Published in Physical Review D

Published
2021

4. Measurement of the anomalous precession frequency of the muon in the Fermilab Muon Experiment

Author

T. Albahri, A. Anastasi, A. Anisenkov, K. Badgley, S. Bae??ler, I. Bailey, V. ???A. Baranov, E. Barlas-Yucel, T. Barrett, A. Basti, F. Bedeschi, M. Berz, M. Bhattacharya, H. ???P. Binney, P. Bloom, J. Bono, E. Bottalico, T. Bowcock, G. Cantatore, R. ???M. Carey, B. ???C. ???K. Casey, D. Cauz, R. Chakraborty, S. ???P. Chang, A. Chapelain, S. Charity, R. Chislett, J. Choi, Z. Chu, T. ???E. Chupp, S. Corrodi, L. Cotrozzi, J. ???D. Crnkovic, S. Dabagov, P. ???T. Debevec, S. Di Falco, P. Di Meo, G. Di Sciascio, R. Di Stefano, A. Driutti, V. ???N. Duginov, M. Eads, J. Esquivel, M. Farooq, R. Fatemi, C. Ferrari, M. Fertl, A. ???T. Fienberg, A. Fioretti, D. Flay, E. Frle??, N. ???S. Froemming, J. Fry, C. Gabbanini, M. ???D. Galati, S. Ganguly, A. Garcia, J. George, L. ???K. Gibbons, A. Gioiosa, K. ???L. Giovanetti, P. Girotti, W. Gohn, T. Gorringe, J. Grange, S. Grant, F. Gray, S. Haciomeroglu, T. Halewood-Leagas, D. Hampai, F. Han, J. Hempstead, A. ???T. Herrod, D. ???W. Hertzog, G. Hesketh, A. Hibbert, Z. Hodge, J. ???L. Holzbauer, K. ???W. Hong, R. Hong, M. Iacovacci, M. Incagli, P. Kammel, M. Kargiantoulakis, M. Karuza, J. Kaspar, D. Kawall, L. Kelton, A. Keshavarzi, D. Kessler, K. ???S. Khaw, Z. Khechadoorian, N. ???V. Khomutov, B. Kiburg, M. Kiburg, O. Kim, Y. ???I. Kim, B. King, N. Kinnaird, E. Kraegeloh, A. Kuchibhotla, N. ???A. Kuchinskiy, K. ???R. Labe, J. LaBounty, M. Lancaster, M. ???J. Lee, S. Lee, S. Leo, B. Li, D. Li, L. Li, I. Logashenko, A. Lorente Campos, A. Luc??, G. Lukicov, A. Lusiani, A. ???L. Lyon, B. MacCoy, R. Madrak, K. Makino, F. Marignetti, S. Mastroianni, J. ???P. Miller, S. Miozzi, W. ???M. Morse, J. Mott, A. Nath, H. Nguyen, R. Osofsky, S. Park, G. Pauletta, G. ???M. Piacentino, R. ???N. Pilato, K. ???T. Pitts, B. Plaster, D. Po??ani??, N. Pohlman, C. ???C. Polly, J. Price, B. Quinn, N. Raha, S. Ramachandran, E. Ramberg, J. ???L. Ritchie, B. ???L. Roberts, D. ???L. Rubin, L. Santi, C. Schlesier, A. Schreckenberger, Y. ???K. Semertzidis, D. Shemyakin, M. ???W. Smith, M. Sorbara, D. St??ckinger, J. Stapleton, C. Stoughton, D. Stratakis, T. Stuttard, H. ???E. Swanson, G. Sweetmore, D. ???A. Sweigart, M. ???J. Syphers, D. ???A. Tarazona, T. Teubner, A. ???E. Tewsley-Booth, K. Thomson, V. Tishchenko, N. ???H. Tran, W. Turner, E. Valetov, D. Vasilkova, G. Venanzoni, T. Walton, A. Weisskopf, L. Welty-Rieger, P. Winter, A. Wolski, W. Wu, Albahri, T., Anastasi, A., Anisenkov, A., Badgley, K., Bae??ler, S., Bailey, I., Baranov, V. ???A., Barlas-Yucel, E., Barrett, T., Basti, A., Bedeschi, F., Berz, M., Bhattacharya, M., Binney, H. ???P., Bloom, P., Bono, J., Bottalico, E., Bowcock, T., Cantatore, G., Carey, R. ???M., Casey, B. ???C. ???K., Cauz, D., Chakraborty, R., Chang, S. ???P., Chapelain, A., Charity, S., Chislett, R., Choi, J., Chu, Z., Chupp, T. ???E., Corrodi, S., Cotrozzi, L., Crnkovic, J. ???D., Dabagov, S., Debevec, P. ???T., Di Falco, S., Di Meo, P., Di Sciascio, G., Di Stefano, R., Driutti, A., Duginov, V. ???N., Eads, M., Esquivel, J., Farooq, M., Fatemi, R., Ferrari, C., Fertl, M., Fienberg, A. ???T., Fioretti, A., Flay, D., Frle??, E., Froemming, N. ???S., Fry, J., Gabbanini, C., Galati, M. ???D., Ganguly, S., Garcia, A., George, J., Gibbons, L. ???K., Gioiosa, A., Giovanetti, K. ???L., Girotti, P., Gohn, W., Gorringe, T., Grange, J., Grant, S., Gray, F., Haciomeroglu, S., Halewood-Leagas, T., Hampai, D., Han, F., Hempstead, J., Herrod, A. ???T., Hertzog, D. ???W., Hesketh, G., Hibbert, A., Hodge, Z., Holzbauer, J. ???L., Hong, K. ???W., Hong, R., Iacovacci, M., Incagli, M., Kammel, P., Kargiantoulakis, M., Karuza, M., Kaspar, J., Kawall, D., Kelton, L., Keshavarzi, A., Kessler, D., Khaw, K. ???S., Khechadoorian, Z., Khomutov, N. ???V., Kiburg, B., Kiburg, M., Kim, O., Kim, Y. ???I., King, B., Kinnaird, N., Kraegeloh, E., Kuchibhotla, A., Kuchinskiy, N. ???A., Labe, K. ???R., Labounty, J., Lancaster, M., Lee, M. ???J., Lee, S., Leo, S., Li, B., Li, D., Li, L., Logashenko, I., Lorente Campos, A., Luc??, A., Lukicov, G., Lusiani, A., Lyon, A. ???L., Maccoy, B., Madrak, R., Makino, K., Marignetti, F., Mastroianni, S., Miller, J. ???P., Miozzi, S., Morse, W. ???M., Mott, J., Nath, A., Nguyen, H., Osofsky, R., Park, S., Pauletta, G., Piacentino, G. ???M., Pilato, R. ???N., Pitts, K. ???T., Plaster, B., Po??ani??, D., Pohlman, N., Polly, C. ???C., Price, J., Quinn, B., Raha, N., Ramachandran, S., Ramberg, E., Ritchie, J. ???L., Roberts, B. ???L., Rubin, D. ???L., Santi, L., Schlesier, C., Schreckenberger, A., Semertzidis, Y. ???K., Shemyakin, D., Smith, M. ???W., Sorbara, M., St??ckinger, D., Stapleton, J., Stoughton, C., Stratakis, D., Stuttard, T., Swanson, H. ???E., Sweetmore, G., Sweigart, D. ???A., Syphers, M. ???J., Tarazona, D. ???A., Teubner, T., Tewsley-Booth, A. ???E., Thomson, K., Tishchenko, V., Tran, N. ???H., Turner, W., Valetov, E., Vasilkova, D., Venanzoni, G., Walton, T., Weisskopf, A., Welty-Rieger, L., Winter, P., Wolski, A., and Wu, W.

Abstract

The Muon g−2 Experiment at Fermi National Accelerator Laboratory (FNAL) has measured the muon anomalous precession frequency ωma to an uncertainty of 434 parts per billion (ppb), statistical, and 56 ppb, systematic, with data collected in four storage ring configurations during its first physics run in 2018. When combined with a precision measurement of the magnetic field of the experiment’s muon storage ring, the precession frequency measurement determines a muon magnetic anomaly of aμ(FNAL)=116592040(54)×10−11 (0.46 ppm). This article describes the multiple techniques employed in the reconstruction, analysis, and fitting of the data to measure the precession frequency. It also presents the averaging of the results from the 11 separate determinations of ωma, and the systematic uncertainties on the result.

Published
2021

5. Magnetic Field Measurement and Analysis for the Muon g-2 Experiment at Fermilab

Author

Z. Chu, M. Eads, M. Lancaster, T. Halewood-Leagas, D. Flay, I. Logashenko, N. A. Kuchinskiy, M. W. Smith, Y. I. Kim, S.B. Dabagov, B. MacCoy, N. H. Tran, K. W. Hong, Liang Li, L. Santi, A. Chapelain, K. S. Khaw, K. T. Pitts, R. Fatemi, I. R. Bailey, E. Bottalico, Andrzej Wolski, R. N. Pilato, P. Bloom, M. Iacovacci, G. Pauletta, M. Incagli, R. Di Stefano, Timothy Chupp, E. Barlas-Yucel, G. Di Sciascio, G. Sweetmore, D. Cauz, P. Girotti, H. Nguyen, Thomas Teubner, D.A. Sweigart, A. E. Tewsley-Booth, G. Piacentino, D. Stöckinger, Karie Badgley, L. Kelton, P. Winter, Brad Plaster, J. L. Holzbauer, R. Chislett, B. Quinn, R. M. Carey, A. Conway, Kyoko Makino, A. Hibbert, B. C. K. Casey, A. Driutti, J. George, A. Lorente Campos, W. Turner, A. Lucà, S. Ramachandran, W. Wu, G. Hesketh, E. Valetov, E. Kraegeloh, Franco Bedeschi, A. Gioiosa, P. T. Debevec, L. Cotrozzi, V. N. Duginov, S. Corrodi, S. Miozzi, Yannis K. Semertzidis, M. J. Lee, S. Mastroianni, P. Di Meo, Martin Berz, K. L. Giovanetti, D. Stratakis, G. Lukicov, C. Gabbanini, J.B. Hempstead, A. Weisskopf, V. Tishchenko, B. Kiburg, H. E. Swanson, O. Kim, Michael Syphers, R. Osofsky, T. Stuttard, J. Esquivel, Dariush Hampai, T. J. V. Bowcock, Adam L. Lyon, Z. Khechadoorian, Meghna Bhattacharya, T. Barrett, Martin Fertl, D. Shemyakin, V. A. Baranov, Manolis Kargiantoulakis, R. Madrak, Marin Karuza, D. Vasilkova, S. Park, N. Kinnaird, A. Lusiani, T. Albahri, E. Ramberg, Nicholas A. Pohlman, D. Kawall, A. Schreckenberger, J. L. Ritchie, A. T. Herrod, Selcuk Haciomeroglu, L. K. Gibbons, J. Stapleton, Fabrizio Marignetti, K. Thomson, J. LaBounty, W. Gohn, G. Venanzoni, B. Li, Claudio Ferrari, Dinko Pocanic, S. P. Chang, S. Charity, T. Walton, T. P. Gorringe, Benjamin T. King, A. Fioretti, A. Anastasi, Sudeshna Ganguly, S. Lee, Ran Hong, M. D. Galati, A.T. Fienberg, William Morse, L. Welty-Rieger, Alejandro Garcia, J. Grange, J. Choi, Dongdong Li, D. W. Hertzog, A. Keshavarzi, M. Sorbara, F. Han, J. Bono, J. Mott, P. Kammel, C. Schlesier, Giovanni Cantatore, S. Di Falco, R. Chakraborty, C. C. Polly, J. P. Miller, M. Kiburg, J. Kaspar, David Rubin, S. Baeßler, K. R. Labe, N. S. Froemming, H. P. Binney, B. L. Roberts, S. Grant, J. Price, N. Raha, Z. Hodge, N. V. Khomutov, M. Farooq, Jason Crnkovic, D. A. Tarazona, C. Stoughton, A. Nath, Frederick Gray, David Kessler, Albahri, T., Anastasi, A., Badgley, K., Baessler, S., Bailey, I., Baranov, V. A., Barlas-Yucel, E., Barrett, T., Bedeschi, F., Berz, M., Bhattacharya, M., Binney, H. P., Bloom, P., Bono, J., Bottalico, E., Bowcock, T., Cantatore, G., Carey, R. M., Casey, B. C. K., Cauz, D., Chakraborty, R., Chang, S. P., Chapelain, A., Charity, S., Chislett, R., Choi, J., Chu, Z., Chupp, T. E., Conway, A., Corrodi, S., Cotrozzi, L., Crnkovic, J. D., Dabagov, S., Debevec, P. T., Di Falco, S., Di Meo, P., Di Sciascio, G., Di Stefano, R., Driutti, A., Duginov, V. N., Eads, M., Esquivel, J., Farooq, M., Fatemi, R., Ferrari, C., Fertl, M., Fienberg, A. T., Fioretti, A., Flay, D., Froemming, N. S., Gabbanini, C., Galati, M. D., Ganguly, S., Garcia, A., George, J., Gibbons, L. K., Gioiosa, A., Giovanetti, K. L., Girotti, P., Gohn, W., Gorringe, T., Grange, J., Grant, S., Gray, F., Haciomeroglu, S., Halewood-Leagas, T., Hampai, D., Han, F., Hempstead, J., Herrod, A. T., Hertzog, D. W., Hesketh, G., Hibbert, A., Hodge, Z., Holzbauer, J. L., Hong, K. W., Hong, R., Iacovacci, M., Incagli, M., Kammel, P., Kargiantoulakis, M., Karuza, M., Kaspar, J., Kawall, D., Kelton, L., Keshavarzi, A., Kessler, D., Khaw, K. S., Khechadoorian, Z., Khomutov, N. V., Kiburg, B., Kiburg, M., Kim, O., Kim, Y. I., King, B., Kinnaird, N., Kraegeloh, E., Kuchinskiy, N. A., Labe, K. R., Labounty, J., Lancaster, M., Lee, M. J., Lee, S., Li, B., Li, D., Li, L., Logashenko, I., Lorente Campos, A., Luca, A., Lukicov, G., Lusiani, A., Lyon, A. L., Maccoy, B., Madrak, R., Makino, K., Marignetti, F., Mastroianni, S., Miller, J. P., Miozzi, S., Morse, W. M., Mott, J., Nath, A., Nguyen, H., Osofsky, R., Park, S., Pauletta, G., Piacentino, G. M., Pilato, R. N., Pitts, K. T., Plaster, B., Pocanic, D., Pohlman, N., Polly, C. C., Price, J., Quinn, B., Raha, N., Ramachandran, S., Ramberg, E., Ritchie, J. L., Roberts, B. L., Rubin, D. L., Santi, L., Schlesier, C., Schreckenberger, A., Semertzidis, Y. K., Shemyakin, D., Smith, M. W., Sorbara, M., Stockinger, D., Stapleton, J., Stoughton, C., Stratakis, D., Stuttard, T., Swanson, H. E., Sweetmore, G., Sweigart, D. A., Syphers, M. J., Tarazona, D. A., Teubner, T., Tewsley-Booth, A. E., Thomson, K., Tishchenko, V., Tran, N. H., Turner, W., Valetov, E., Vasilkova, D., Venanzoni, G., Walton, T., Weisskopf, A., Welty-Rieger, L., Winter, P., Wolski, A., Wu, W., Baeßler, S., Lucà, A., Počanić, D., and Stöckinger, D.

Subjects
Field (physics), Physics::Instrumentation and Detectors, FOS: Physical sciences, 7. Clean energy, 01 natural sciences, Omega, High Energy Physics - Experiment, 010305 fluids & plasmas, Nuclear physics, High Energy Physics - Experiment (hep-ex), muon, 0103 physical sciences, Proton spin crisis, Fermilab, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Larmor precession, Physics, Muon, Settore FIS/01 - Fisica Sperimentale, VACUUM POLARIZATION CONTRIBUTIONSTEMPERATURE-DEPENDENCEPROTON NMRMOMENTSUSCEPTIBILITYTERMS, anomalous magnetic moment, Muon g-2 Experiment, anomalous precession frequency, Magnetic field, anomalous precession frequency, Muon g-2 Experiment, Fermi Gamma-ray Space Telescope
Abstract

The Fermi National Accelerator Laboratory has measured the anomalous precession frequency $a^{}_\mu = (g^{}_\mu-2)/2$ of the muon to a combined precision of 0.46 parts per million with data collected during its first physics run in 2018. This paper documents the measurement of the magnetic field in the muon storage ring. The magnetic field is monitored by nuclear magnetic resonance systems and calibrated in terms of the equivalent proton spin precession frequency in a spherical water sample at 34.7$^\circ$C. The measured field is weighted by the muon distribution resulting in $\tilde{\omega}'^{}_p$, the denominator in the ratio $\omega^{}_a$/$\tilde{\omega}'^{}_p$ that together with known fundamental constants yields $a^{}_\mu$. The reported uncertainty on $\tilde{\omega}'^{}_p$ for the Run-1 data set is 114 ppb consisting of uncertainty contributions from frequency extraction, calibration, mapping, tracking, and averaging of 56 ppb, and contributions from fast transient fields of 99 ppb., Comment: Added one citation and corrected missing normalization in Eqs (35) and (36)

Published
2021
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6. Beam dynamics corrections to the Run-1 measurement of the muon anomalous magnetic moment at Fermilab

Author

K. S. Khaw, C. Schlesier, Diktys Stratakis, R. Fatemi, S. Corrodi, D. Newton, K. T. Pitts, R. T. Chislett, L. K. Gibbons, Kyoko Makino, E. Bottalico, A. Gioiosa, J. LaBounty, J. Bono, I. R. Bailey, P. Kammel, D. Kawall, T. J. V. Bowcock, H. P. Binney, W. Turner, A. T. Herrod, S. Miozzi, A. Schreckenberger, E. Valetov, N. H. Tran, K. W. Hong, J. Esquivel, M. Sorbara, Christopher Stoughton, Fabrizio Marignetti, A. Lucà, L. Kelton, M. Eads, D. Stöckinger, T. Barrett, G. Piacentino, J. Mott, S. Baeßler, Bck Casey, Kayleigh Anne Thomson, Giovanni Cantatore, Rachel Osofsky, M. Kiburg, E. Barlas-Yucel, Michael Syphers, C. C. Polly, J. Choi, R. Chakraborty, D. Flay, David Rubin, J. Grange, N. A. Kuchinskiy, M. W. Smith, G. Lukicov, M. Iacovacci, G. Pauletta, J. L. Ritchie, B. MacCoy, L. Cotrozzi, V. N. Duginov, A. Lorente Campos, S. Lee, Ran Hong, G. Sweetmore, D.A. Sweigart, M. Korostelev, Dongdong Li, D. W. Hertzog, Alexander Keshavarzi, G. Di Sciascio, Alejandro L. Garcia, Liang Li, F. Han, D. Sathyan, A.T. Fienberg, Sultan B. Dabagov, M. J. Lee, S. P. Chang, Benjamin T. King, Marin Karuza, R. N. Pilato, M. Incagli, J.B. Hempstead, B. Quinn, L. Santi, N. Kinnaird, F. Gray, P. Winter, L. Welty-Rieger, Meghna Bhattacharya, H. Nguyen, P. Di Meo, T. Stuttard, A. L. Lyon, David Kessler, A. Chapelain, J. Kaspar, B. Li, Galati, Sudeshna Ganguly, Andrzej Wolski, A. Driutti, D. A. Tarazona, Brad Plaster, R. M. Carey, D. Cauz, G. Venanzoni, J. Fry, B. Kiburg, J. P. Miller, W. Gohn, B. L. Roberts, S. Grant, V. A. Baranov, Nicholas A. Pohlman, N. V. Khomutov, M. Farooq, Jason Crnkovic, A. Hibbert, K. R. Labe, P. T. Debevec, Thomas Teubner, S. Di Falco, J. D. Price, Yi Kim, I.B. Logashenko, Yannis K. Semertzidis, K. L. Giovanetti, A. E. Tewsley-Booth, E. Frlež, Martin Berz, S. Charity, T. Walton, Z. Khechadoorian, S. Ramachandran, A. Fiedler, T. P. Gorringe, William Morse, A. Fioretti, A. Anastasi, O. Kim, A. Weisskopf, Wanwei Wu, Karie Badgley, S. Mastroianni, J. L. Holzbauer, Manolis Kargiantoulakis, S. Park, A. Lusiani, T. Albahri, R. Madrak, Selcuk Haciomeroglu, Z. Chu, Dariush Hampai, Gavin Grant Hesketh, J. George, Tishchenko, D. Vasilkova, Franco Bedeschi, P. Bloom, Timothy Chupp, P. Girotti, Nathan Froemming, J. Stapleton, Dinko Pocanic, M. Lancaster, C. Gabbanini, N. Raha, H. E. Swanson, Martin Fertl, Z. Hodge, Tabitha Halewood-leagas, E. J. Ramberg, A. Nath, R. Di Stefano, E. Kraegeloh, Claudio Ferrari, Albahri, T., Anastasi, A., Badgley, K., Baessler, S., Bailey, I., Baranov, V. A., Barlas-Yucel, E., Barrett, T., Bedeschi, F., Berz, M., Bhattacharya, M., Binney, H. P., Bloom, P., Bono, J., Bottalico, E., Bowcock, T., Cantatore, G., Carey, R. M., Casey, B. C. K., Cauz, D., Chakraborty, R., Chang, S. P., Chapelain, A., Charity, S., Chislett, R., Choi, J., Chu, Z., Chupp, T. E., Corrodi, S., Cotrozzi, L., Crnkovic, J. D., Dabagov, S., Debevec, P. T., Di Falco, S., Di Meo, P., Di Sciascio, G., Di Stefano, R., Driutti, A., Duginov, V. N., Eads, M., Esquivel, J., Farooq, M., Fatemi, R., Ferrari, C., Fertl, M., Fiedler, A., Fienberg, A. T., Fioretti, A., Flay, D., Frlez, E., Froemming, N. S., Fry, J., Gabbanini, C., Galati, M. D., Ganguly, S., Garcia, A., George, J., Gibbons, L. K., Gioiosa, A., Giovanetti, K. L., Girotti, P., Gohn, W., Gorringe, T., Grange, J., Grant, S., Gray, F., Haciomeroglu, S., Halewood-Leagas, T., Hampai, D., Han, F., Hempstead, J., Herrod, A. T., Hertzog, D. W., Hesketh, G., Hibbert, A., Hodge, Z., Holzbauer, J. L., Hong, K. W., Hong, R., Iacovacci, M., Incagli, M., Kammel, P., Kargiantoulakis, M., Karuza, M., Kaspar, J., Kawall, D., Kelton, L., Keshavarzi, A., Kessler, D., Khaw, K. S., Khechadoorian, Z., Khomutov, N. V., Kiburg, B., Kiburg, M., Kim, O., Kim, Y. I., King, B., Kinnaird, N., Korostelev, M., Kraegeloh, E., Kuchinskiy, N. A., Labe, K. R., Labounty, J., Lancaster, M., Lee, M. J., Lee, S., Li, B., Li, D., Li, L., Logashenko, I., Lorente Campos, A., Luca, A., Lukicov, G., Lusiani, A., Lyon, A. L., Maccoy, B., Madrak, R., Makino, K., Marignetti, F., Mastroianni, S., Miller, J. P., Miozzi, S., Morse, W. M., Mott, J., Nath, A., Newton, D., Nguyen, H., Osofsky, R., Park, S., Pauletta, G., Piacentino, G. M., Pilato, R. N., Pitts, K. T., Plaster, B., Pocanic, D., Pohlman, N., Polly, C. C., Price, J., Quinn, B., Raha, N., Ramachandran, S., Ramberg, E., Ritchie, J. L., Roberts, B. L., Rubin, D. L., Santi, L., Sathyan, D., Schlesier, C., Schreckenberger, A., Semertzidis, Y. K., Smith, M. W., Sorbara, M., Stockinger, D., Stapleton, J., Stoughton, C., Stratakis, D., Stuttard, T., Swanson, H. E., Sweetmore, G., Sweigart, D. A., Syphers, M. J., Tarazona, D. A., Teubner, T., Tewsley-Booth, A. E., Thomson, K., Tishchenko, V., Tran, N. H., Turner, W., Valetov, E., Vasilkova, D., Venanzoni, G., Walton, T., Weisskopf, A., Welty-Rieger, L., Winter, P., Wolski, A., and Wu, W.

Subjects
Larmor precession, Physics, Accelerator Physics (physics.acc-ph), Nuclear and High Energy Physics, Muon, Physics and Astronomy (miscellaneous), Anomalous magnetic dipole moment, 010308 nuclear & particles physics, FOS: Physical sciences, Surfaces and Interfaces, 01 natural sciences, High Energy Physics - Experiment, Magnetic field, Nuclear physics, High Energy Physics - Experiment (hep-ex), muon magnetic anomaly, 0103 physical sciences, Physics - Accelerator Physics, Fermilab, Pitch angle, 010306 general physics, G-2 EXPERIMENTFREQUENCY, Storage ring, Beam (structure)
Abstract

This paper presents the beam dynamics systematic corrections and their uncertainties for the Run-1 data set of the Fermilab Muon g-2 Experiment. Two corrections to the measured muon precession frequency $\omega_a^m$ are associated with well-known effects owing to the use of electrostatic quadrupole (ESQ) vertical focusing in the storage ring. An average vertically oriented motional magnetic field is felt by relativistic muons passing transversely through the radial electric field components created by the ESQ system. The correction depends on the stored momentum distribution and the tunes of the ring, which has relatively weak vertical focusing. Vertical betatron motions imply that the muons do not orbit the ring in a plane exactly orthogonal to the vertical magnetic field direction. A correction is necessary to account for an average pitch angle associated with their trajectories. A third small correction is necessary because muons that escape the ring during the storage time are slightly biased in initial spin phase compared to the parent distribution. Finally, because two high-voltage resistors in the ESQ network had longer than designed RC time constants, the vertical and horizontal centroids and envelopes of the stored muon beam drifted slightly, but coherently, during each storage ring fill. This led to the discovery of an important phase-acceptance relationship that requires a correction. The sum of the corrections to $\omega_a^m$ is 0.50 $\pm$ 0.09 ppm; the uncertainty is small compared to the 0.43 ppm statistical precision of $\omega_a^m$., Comment: 35 pages, 29 figures. Accepted by Phys. Rev. Accel. Beams

Published
2021
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7. Demonstration of Muon-Beam Transverse Phase-Space Compression

Author

Andreas Eggenberger, K. S. Khaw, Florian M. Piegsa, Gunther Wichmann, Andreas Knecht, Ryoto Iwai, Narongrit Ritjoho, C. Petitjean, Angela Papa, Thomas J. Phillips, N. J. Ayres, V. Bondar, Klaus Kirch, Aldo Antognini, D. Taqqu, Daniel M. Kaplan, Ivana Belosevic, Alexey Stoykov, and Malte Hildebrandt

Subjects
Physics, Accelerator Physics (physics.acc-ph), Muon, Density gradient, 010308 nuclear & particles physics, Muonium, General Physics and Astronomy, FOS: Physical sciences, 01 natural sciences, Magnetic field, Transverse plane, Compression (functional analysis), Phase space, 0103 physical sciences, Physics::Accelerator Physics, Physics - Accelerator Physics, Atomic physics, 010306 general physics, Beam (structure)
Abstract

We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14 mm was reduced to a 0.25 mm size (rms) within 3.5 μs. The simulation including cross sections for low-energy μ+-He elastic and charge exchange (μ+↔ muonium) collisions describes the measurements well. By combining the transverse compression stage with a previously demonstrated longitudinal compression stage, we can improve the phase space density of a μ+ beam by a factor of 1010 with 10−3 efficiency., Physical Review Letters, 125 (16), ISSN:0031-9007, ISSN:1079-7114

Published
2020

8. muCool: a next step towards efficient muon beam compression

Author

Angela Papa, Alexey Stoykov, Andreas Eggenberger, Thomas J. Phillips, Malte Hildebrandt, Narongrit Ritjoho, Andreas Knecht, Daniel M. Kaplan, Ivana Belosevic, K. S. Khaw, Klaus Kirch, Aldo Antognini, Florian M. Piegsa, Gunther Wichmann, C. Petitjean, Ryoto Iwai, Yu Bao, and D. Taqqu

Subjects
Physics, Accelerator Physics (physics.acc-ph), Muon, Physics and Astronomy (miscellaneous), Physics::Instrumentation and Detectors, FOS: Physical sciences, lcsh:Astrophysics, 01 natural sciences, Magnetic field, Nuclear physics, Phase space, Electric field, lcsh:QB460-466, 0103 physical sciences, Perpendicular, lcsh:QC770-798, Physics::Accelerator Physics, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, High Energy Physics::Experiment, Physics - Accelerator Physics, Beam emittance, 010306 general physics, Engineering (miscellaneous), Energy (signal processing), Beam (structure)
Abstract

A novel device to compress the phase space of a muon beam by a factor of 1010 with a 10−3 efficiency is under development. A surface muon beam is stopped in a helium gas target consisting of several compression stages, wherein strong electric and magnetic fields are applied. The spatial extent of the stopped muon swarm is decreased by means of these fields until muons with eV energy are extracted into vacuum through a small orifice. It was observed that a 20 cm long muon stop distribution can be compressed in the longitudinal direction to a sub-mm extent within 2 μs. Additionally, a drift perpendicular to the magnetic field of the compressed low-energy muon swarm was successfully demonstrated, paving the way towards extraction from the gas and re-acceleration of the muons., The European Physical Journal C, 79 (5), ISSN:1434-6044, ISSN:1434-6052

Published
2019

9. Performance of the Muon g−2 calorimeter and readout systems measured with test beam data

Author

D.A. Peterson, M. Bartolini, K. L. Giovanetti, N.T. Rider, A. Kuchibhotla, A. Gioiosa, S. Ganguly, A.T. Fienberg, A. Chapelain, H. P. Binney, W. Gohn, R. Bjorkquist, J. Kaspar, C. Schlesier, T. P. Gorringe, M. Iacovacci, A. Driutti, A. Lusiani, S. Leo, M. W. Smith, T. Stuttard, D. W. Hertzog, G. Pauletta, S. Mastroianni, L. K. Gibbons, Dinko Pocanic, G. Venanzoni, Claudio Ferrari, D.A. Sweigart, T. D. Van Wechel, K. S. Khaw, J.B. Hempstead, C. Gabbanini, and A. Fioretti

Subjects
Physics, Nuclear and High Energy Physics, Muon, Calorimeter (particle physics), Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, business.industry, Electrical engineering, 7. Clean energy, 01 natural sciences, Silicon photomultiplier, Data acquisition, 0103 physical sciences, Calibration, Waveform, Fermilab, Electronics, 010306 general physics, business, Instrumentation
Abstract

A single calorimeter station for the Muon g − 2 experiment at Fermilab includes the following subsystems: a 54-element array of PbF 2 Cherenkov crystals read out by large-area SiPMs, bias and slow-control electronics, a suite of 800 MSPS waveform digitizers, a clock and control distribution network, a gain calibration and monitoring system, and a GPU-based front-end which is read out through a MIDAS data acquisition environment. The entire system performance was evaluated using 2.5–5 GeV electrons at the End Station Test Beam at SLAC. This paper includes a description of the individual subsystems and the results of measurements of the energy response and resolution, energy-scale stability, timing resolution, and spatial uniformity. All measured performances meet or exceed the g − 2 experimental requirements. Based on the success of the tests, the complete production of the required 24 calorimeter stations has been made and installation into the main experiment is complete. Furthermore, the calorimeter response measurements reported here informed the design of the reconstruction algorithms that are now employed in the running g − 2 experiment.

Published
2019

10. Expression of Interest for Evolution of the Mu2e Experiment

Author

R. Bonventre, G. Lukicov, R. Culbertson, P. Q. Hung, Brian Pollack, R. Tschirhart, A. Lucà, S. Giovannella, A. Mazzacane, Michael Schmitt, S. Donati, L. Xia, S. Boi, Y. Wang, K. S. Khaw, P. Murat, F. C. Porter, V. Lombardo, S. Mueller, Z. Usubov, Mayda Velasco, J. Whitmore, Gianantonio Pezzullo, B. Kiburg, Y. Oksuzian, J. P. Miller, Rashid M. Djilkibaev, M. Röhrken, David Neuffer, V. Giusti, J. Bono, R. Hooper, L. Harkness-Brennan, P. Fabbricatore, C. Gatto, G. Drake, D. Ambrose, M. Jones, M. Jenkins, Manolis Kargiantoulakis, J. F. Caron, S. Denisov, K. Heller, G. Horton-Smith, D. Glenzinski, F. Abusalma, S. Demers, C. Bloise, Dmitri Denisov, R. Coleman, K. L. Byrum, Ren-Yuan Zhu, A. Gaponenko, Markus Frank, Y. I. Davydov, Aji Daniel, R. Ciolini, V. Evdokimov, S. Miscetti, B. Echenard, D. Pasciuto, E. Diociaiuti, R. Zwaska, Steven Werkema, A. Artikov, D. Cronin-Hennessy, V. Zutshi, M. Ricci, D. Lin, Henry Glass, Richard L. Talaga, M. A. Cummings, Vitaly Pronskikh, A. Popov, P. Winter, D. Stratakis, Anna Pla-Dalmau, A. Edmonds, James L. Popp, N. H. Tran, L. Goodenough, E. Pedreschi, Luca Morescalchi, G. C. Blazey, D. G. Hitlin, John Quirk, D. Chokheli, F. Spinella, E. Prebys, K. R. Lynch, D. Pushka, A. Saputi, J. Mott, V. Nagaslaev, F. Happacher, S. Di Falco, M. Campbell, F. Cervelli, D. N. Brown, R. H. Bernstein, C. Hu, D. Hedin, Robert K. Kutschke, A. Hocker, J. Kozminski, M. Martini, A. Ferrari, R. Ehrlich, Thomas Strauss, Yu.G. Kolomensky, T. A. Bolton, I. Logashenko, Ed V. Hungerford, R. L. Wagner, D. Bowring, Z. Giorgio, E. C. Dukes, R. Donghia, K. Ciampa, V. Tereshchenko, L. Zhang, V. Rusu, M. Lancaster, Gregory Rakness, R. E. Ray, and I. Sarra

Subjects
Particle physics, Upgrade, Leverage (negotiation), Physics::Instrumentation and Detectors, Computer science, Mu2e, Detector, Physics::Accelerator Physics, High Energy Physics::Experiment, Fermilab, Sensitivity (control systems), Order of magnitude, Lepton
Abstract

We propose an evolution of the Mu2e experiment, called Mu2e-II, that would leverage advances in detector technology and utilize the increased proton intensity provided by the Fermilab PIP-II upgrade to improve the sensitivity for neutrinoless muon-to-electron conversion by one order of magnitude beyond the Mu2e experiment, providing the deepest probe of charged lepton flavor violation in the foreseeable future. Mu2e-II will use as much of the Mu2e infrastructure as possible, providing, where required, improvements to the Mu2e apparatus to accommodate the increased beam intensity and cope with the accompanying increase in backgrounds.

Published
2018

11. Muon g-2 reconstruction and analysis framework for the muon anomalous precession frequency

Author

K. S. Khaw

Subjects
Physics, Larmor precession, History, Measure (data warehouse), Muon, Physics - Instrumentation and Detectors, Anomalous magnetic dipole moment, Physics::Instrumentation and Detectors, Detector, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), Computer Science Applications, Education, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), Data quality, Physics::Accelerator Physics, High Energy Physics::Experiment, Fermilab, Beam (structure)
Abstract

The Muon g-2 experiment at Fermilab, with the aim to measure the muon anomalous magnetic moment to an unprecedented level of 140~ppb, has started beam and detector commissioning in Summer 2017. To deal with incoming data projected to be around tens of petabytes, a robust data reconstruction and analysis chain based on Fermilab's \textit{art} event-processing framework is developed. Herein, I report the current status of the framework, together with its novel features such as multi-threaded algorithms for online data quality monitor (DQM) and fast-turnaround operation (nearline). Performance of the framework during the commissioning run is also discussed., Comment: 6 pages, 6 figures, the 18th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2017)

Published
2017
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12. Spatial confinement of muonium atoms

Author

Zaher Salman, Laszlo Liszkay, K. S. Khaw, Paolo Crivelli, Thomas Prokscha, Klaus Kirch, Aldo Antognini, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), and Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay

Subjects
Atomic Physics (physics.atom-ph), measurement methods, Muonium, FOS: Physical sciences, Electron, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, Physics - Atomic Physics, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), [ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex], 0103 physical sciences, Bound state, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], [ PHYS.PHYS.PHYS-GEN-PH ] Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Physics::Atomic Physics, 010306 general physics, Spectroscopy, [ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Physics, muonium, Muon, Mesoporous silica, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], laser, Reflection (mathematics), confinement, spectrometer, silicon: oxygen, atom: excited state, Atomic physics, Law of cosines
Abstract

We report the achievement of spatial confinement of muonium atoms (the bound state of a positive muon and an electron). Muonium emitted into vacuum from mesoporous silica reflects between two SiO$_2$ confining surfaces separated by 1 mm. From the data, one can extract that the reflection probability on the confining surfaces kept at 100 K is about 90% and the reflection process is well described by a cosine law. This technique enables new experiments with this exotic atomic system and is a very important step towards a measurement of the 1S-2S transition frequency using continuous wave laser spectroscopy., 5 pages, 6 figures

Published
2016

13. Geant4 simulation of the PSI LEM beam line: energy loss and muonium formation in thin foils and the impact of unmoderated muons on the $\mu$SR spectrometer

Author

K. S. Khaw, Klaus Kirch, Aldo Antognini, Elvezio Morenzoni, Zaher Salman, Thomas Prokscha, Andreas Suter, and Paolo Crivelli

Subjects
Materials science, Muon, Physics - Instrumentation and Detectors, Spectrometer, 010308 nuclear & particles physics, Physics::Instrumentation and Detectors, Cyclotron, Muonium, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), Muon spin spectroscopy, Kinetic energy, 01 natural sciences, law.invention, Nuclear physics, law, 0103 physical sciences, Physics::Accelerator Physics, High Energy Physics::Experiment, 010306 general physics, Instrumentation, Mathematical Physics, Beam (structure), Lepton
Abstract

The PSI low-energy $��$SR spectrometer is an instrument dedicated to muon spin rotation and relaxation measurements. Knowledge of the muon beam parameters such as spatial, kinetic energy and arrival-time distributions at the sample position are important ingredients to analyze the $��$SR spectra. We present here the measured energy losses in the thin carbon foil of the muon start detector deduced from time-of-flight measurements. Muonium formation in the thin carbon foil (10 nm thickness) of the muon start detector also affect the measurable decay asymmetry and therefore need to be accounted for. Muonium formation and energy losses in the start detector, whose relevance increase with decreasing muon implantation energy ($, Paper submitted to JINST for review on 15th Jun 2015

Published
2015

14. The New Muon g-2 experiment at Fermilab

Author

B. Abi T. Albahri, S. Al-Kilani, D. Allspach, L. P. Alonzi, A. Anastasi, F. Azfar, D. Babusci, S. Baessler, V. A. Baranov, E. Barzi, R. Bjorkquist, T. Bowcock, G. Cantatore, R. M. Carey, J. Carroll, B. Casey, D. Cauz, A. Chapelain, S. Chappa, S. Chattopadhyay, R. Chislett, T. E. Chupp, M. Convery, G. Corradi, J. Crnkovic, S. Dabagov, P. T. Debevec, G. Di Sciascio, R. Di Stefano, B. Drendel, V. P. Druzhinin, V. N. Duginov, M. Eads, N. Eggert, A. Epps, R. Fatemi, C. Ferrari, M. Fertl, A. T. Fienberg, A. Fioretti, D. Flay, A. S. Frankenthal, H. Friedsam, E. Frlez, N. S. Froemming, C. Fu, C. Gabbanini, M. Gaisser, S. Ganguly, A. Garcia, J. George, L. K. Gibbons, K. L. Giovanetti, S. Goadhouse, W. Gohn, T. Gorringe, J. Grange, F. Gray, S. Haciomeroglu, T. Halewood-Leagas, D. Hampai, E. Hazen, S. Henry, D. W. Hertzog, J. L. Holzbauer, M. Iacovacci, C. Johnstone, J. A. Johnstone, K. Jungmann, H. Kamal Sayed, P. Kammel, M. Karuza, J. Kaspar, D. Kawall, L. Kelton, K. S. Khaw, N. V. Khomutov, B. Kiburg, S. C. Kim, Y. I. Kim, B. King, N. Kinnaird, I. A. Koop, I. Kourbanis, V. A. Krylov, A. Kuchibhotla, N. A. Kuchinskiy, M. Lancaster, M. J. Lee, S. Lee, S. Leo, L. Li, I. Logashenko, G. Luo, K. R. Lynch, A. Lyon, S. Marignetti, S. Mastroianni, S. Maxfield, M. McEvoy, Z. Meadows, W. Merritt, A. A. Mikhailichenko, J. P. Miller, J. P. Morgan, D. Moricciani, W. M. Morse, J. Mott, E. Motuk, H. Nguyen, Y. Orlov, R. Osofsky, J. -F. Ostiguy, A. Palladino, G. Pauletta, K. Pitts, D. Pocanic, N. Pohlman, C. Polly, J. Price, B. Quinn, N. Raha, E. Ramberg, N. T. Rider, J. L. Ritchie, B. L. Roberts, M. Rominsky, D. L. Rubin, L. Santi, C. Schlesier, Y. K. Semertzidis, Y. M. Shatunov, M. Shenk, A. Smith, M. W. Smith, A. Soha, E. Solodov, D. Still, D. Stöckinger, T. Stuttard, H. E. Swanson, D. A. Sweigart, M. J. Syphers, S. Szustkowski, D. Tarazona, T. Teubner, A. E. Tewlsey-Booth, V. Tishchenko, G. Venanzoni, V. P. Volnykh, T. Walton, M. Warren, L. Welty-Rieger, M. Whitley, P. Winter, A. Wolski, E. Won, M. Wormald, W. Wu, H. Yang, C. Yoshikawa, Albahri, B. Abi T., Al-Kilani, S., Allspach, D., Alonzi, L. P., Anastasi, A., Azfar, F., Babusci, D., Baessler, S., Baranov, V. A., Barzi, E., Bjorkquist, R., Bowcock, T., Cantatore, G., Carey, R. M., Carroll, J., Casey, B., Cauz, D., Chapelain, A., Chappa, S., Chattopadhyay, S., Chislett, R., Chupp, T. E., Convery, M., Corradi, G., Crnkovic, J., Dabagov, S., Debevec, P. T., Di Sciascio, G., Di Stefano, R., Drendel, B., Druzhinin, V. P., Duginov, V. N., Eads, M., Eggert, N., Epps, A., Fatemi, R., Ferrari, C., Fertl, M., Fienberg, A. T., Fioretti, A., Flay, D., Frankenthal, A. S., Friedsam, H., Frlez, E., Froemming, N. S., Fu, C., Gabbanini, C., Gaisser, M., Ganguly, S., Garcia, A., George, J., Gibbons, L. K., Giovanetti, K. L., Goadhouse, S., Gohn, W., Gorringe, T., Grange, J., Gray, F., Haciomeroglu, S., Halewood-Leagas, T., Hampai, D., Hazen, E., Henry, S., Hertzog, D. W., Holzbauer, J. L., Iacovacci, M., Johnstone, C., Johnstone, J. A., Jungmann, K., Kamal Sayed, H., Kammel, P., Karuza, M., Kaspar, J., Kawall, D., Kelton, L., Khaw, K. S., Khomutov, N. V., Kiburg, B., Kim, S. C., Kim, Y. I., King, B., Kinnaird, N., Koop, I. A., Kourbanis, I., Krylov, V. A., Kuchibhotla, A., Kuchinskiy, N. A., Lancaster, M., Lee, M. J., Lee, S., Leo, S., Li, L., Logashenko, I., Luo, G., Lynch, K. R., Lyon, A., Marignetti, S., Mastroianni, S., Maxfield, S., Mcevoy, M., Meadows, Z., Merritt, W., Mikhailichenko, A. A., Miller, J. P., Morgan, J. P., Moricciani, D., Morse, W. M., Mott, J., Motuk, E., Nguyen, H., Orlov, Y., Osofsky, R., Ostiguy, J. -F., Palladino, A., Pauletta, G., Pitts, K., Pocanic, D., Pohlman, N., Polly, C., Price, J., Quinn, B., Raha, N., Ramberg, E., Rider, N. T., Ritchie, J. L., Roberts, B. L., Rominsky, M., Rubin, D. L., Santi, L., Schlesier, C., Semertzidis, Y. K., Shatunov, Y. M., Shenk, M., Smith, A., Smith, M. W., Soha, A., Solodov, E., Still, D., Stöckinger, D., Stuttard, T., Swanson, H. E., Sweigart, D. A., Syphers, M. J., Szustkowski, S., Tarazona, D., Teubner, T., Tewlsey-Booth, A. E., Tishchenko, V., Venanzoni, G., Volnykh, V. P., Walton, T., Warren, M., Welty-Rieger, L., Whitley, M., Winter, P., Wolski, A., Won, E., Wormald, M., Wu, W., Yang, H., and Yoshikawa, C.

Subjects
Precision Physics, Muon magnetic anomaly, Muon g-2 experiment
Abstract

There is a long standing discrepancy between the Standard Model prediction for the muon and the value measured by the Brookhaven E821 Experiment. At present the discrepancy stands at about three standard deviations, with a comparable accuracy between experiment and theory. Two new proposals – at Fermilab and J-PARC – plan to improve the experimental uncertainty by a factor of 4, and it is expected that there will be a significant reduction in the uncertainty of the Standard Model prediction. I will review the status of the planned experiment at Fermilab, E989, which will analyse 21 times more muons than the BNL experiment and discuss how the systematic uncertainty will be reduced by a factor of 3 such that a precision of 0.14 ppm can be achieved.

Published
2015

15. Muon cooling: longitudinal compression

Author

Wilhelm Bertl, Klaus Kirch, Yu Bao, Aldo Antognini, Malte Hildebrandt, D. Taqqu, Florian M. Piegsa, Angela Papa, Alexey Stoykov, Kamil Sedlak, C. Petitjean, Stefan Ritt, and K. S. Khaw

Subjects
Accelerator Physics (physics.acc-ph), Physics, Surface (mathematics), Muon, Physics::Instrumentation and Detectors, FOS: Physical sciences, General Physics and Astronomy, Order (ring theory), 7. Clean energy, Magnetic field, Nuclear physics, Microsecond, Compression (functional analysis), Phase space, Physics::Accelerator Physics, Physics - Accelerator Physics, Beam (structure)
Abstract

A 10 MeV/c $\mu^+$ beam was stopped in helium gas of a few mbar in a magnetic field of 5 T. The muon 'swarm' has been efficiently compressed from a length of 16 cm down to a few mm along the magnetic field axis (longitudinal compression) using electrostatic fields. The simulation reproduces the low energy interactions of slow muons in helium gas. Phase space compression occurs on the order of microseconds, compatible with the muon lifetime of 2 $\mu$s. This paves the way for preparation of a high quality muon beam., Comment: 5 pages, 6 figures

Published
2014

16. Testing antimatter gravity with muonium

Author

Klaus Kirch and K. S. Khaw

Subjects
Phase space compression, Gravity (chemistry), Physics::General Physics, Physics - Instrumentation and Detectors, Atomic Physics (physics.atom-ph), Muonium, FOS: Physical sciences, 01 natural sciences, Physics - Atomic Physics, Acceleration, Gravitational potential, General Relativity and Quantum Cosmology, Physics::Popular Physics, Gravitational field, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Annual variation, Physics::Atomic Physics, 010306 general physics, Spectroscopy, Physics, 010308 nuclear & particles physics, Antimatter gravity, Astronomy, Mach-Zehnder interferometer, Muon spin rotation, Superfluid helium, Instrumentation and Detectors (physics.ins-det), Redshift, Antimatter
Abstract

The debate about how antimatter or different antimatter systems behave gravitationally will be ultimately decided by experiments measuring directly the acceleration of various antimatter probes in the gravitational field of the Earth or perhaps redshift effects in antimatter atoms caused by the annual variation of the Sun's gravitational potential at the location of the Earth. Muonium atoms may be used to probe the gravitational interaction of leptonic, second generation antimatter. We discuss the progress of our work towards enabling such experiments with muonium., International Journal of Modern Physics: Conference Series, 30, ISSN:2010-1945

Published
2014
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17. Metaraminol Infusion for Maintenance of Arterial Blood Pressure During Spinal Anesthesia for Cesarean Delivery: The Effect of a Crystalloid Bolus

Author

F F Ng, W.D. Ngan Kee, K S Khaw, M M Wong, and B B Lee

Subjects
Adult, Hemodynamics, Blood Pressure, Anesthesia, Spinal, Bolus (medicine), Pregnancy, Heart rate, Elective Cesarean Delivery, medicine, Anesthesia, Obstetrical, Humans, Vasoconstrictor Agents, Prospective Studies, Infusions, Intravenous, Metaraminol, Cesarean Section, business.industry, Infant, Newborn, Pregnancy Outcome, Anesthesiology and Pain Medicine, Blood pressure, Anesthesia, Female, Complication, business, Perfusion, medicine.drug
Abstract

We randomly allocated women having elective cesarean delivery to receive either no bolus (Control Group, n = 31) or 20 mL/kg lactated Ringer's solution (Bolus Group, n = 35) IV before spinal anesthesia. An infusion of metaraminol started at 0.25 mg/min was titrated to maintain systolic arterial blood pressure in the target range 90%-100% of baseline. The total dose of metaraminol required up to the time of uterine incision was similar between the Control Group and the Bolus Group (3.62 +/- 1.20 vs 3.27 +/- 1.39 mg, P = 0.3). However, the Control Group required more metaraminol in the first 5 min (1.29 +/- 0.60 vs 0.96 +/- 0.58 mg, P = 0.025) and a faster maximum infusion rate (0.45 +/- 0.20 vs 0.32 +/- 0.13 mg/min, P = 0.002) compared with the Bolus Group. There was no difference between groups in regards to changes in systolic arterial blood pressure or heart rate over time, or maternal or neonatal outcome. We conclude that when metaraminol is used to maintain arterial pressure during spinal anesthesia for cesarean delivery, crystalloid bolus is not essential provided that sufficient vasopressor is given in the immediate postspinal period.

Published
2001

18. Ist Noradrenalin Phenylephrin bei der Sectio überlegen?

Author

F F Ng, P E Tan, W D Ngan Kee, K S Khaw, and S W Lee

Abstract

Um Blutdruckabfalle bei der Spinalanasthesie zum Kaiserschnitt zu kupieren, wird insbesondere im angloamerikanischen Sprachraum Phenylephrin eingesetzt. Als kunstliches Katecholamin hat es starke α-adrenerge Wirkungen bei fehlendem β-adrenergen Einfluss, sodass man dosisabhangig einen Abfall der Herzfrequenz und des Herzminutenvolumens beobachten kann. Klinisch hat dies bei gesunder Mutter und Kind keine Bedeutung, allerdings bestehen Bedenken bei kompromittierten Kindern. Daher scheint eine Alternative erforderlich zu sein.

Published
2015

19. Measurements of tissue viability in transplantation

Author

S. Simpkin, Maureen S. Thorniley, C. Shurey, K. S. Khaw, C. J. Green, E. Balogun, and K. Burton

Subjects
Male, medicine.medical_specialty, Spectrophotometry, Infrared, Hemodynamics, Blood volume, Biology, Transplantation, Autologous, Surgical Flaps, General Biochemistry, Genetics and Molecular Biology, Hemoglobins, Hyperaemia, Internal medicine, medicine, Animals, Humans, Cerebral perfusion pressure, Transplantation, Graft Survival, Oxygenation, Pedicled Flap, Anatomy, Liver Transplantation, Rats, Transplantation, Isogeneic, Rats, Inbred Lew, Oxyhemoglobins, Cardiology, medicine.symptom, General Agricultural and Biological Sciences, Perfusion, Research Article, Liver Circulation
Abstract

Near–infrared spectroscopy has primarily been used in monitoring changes in cerebral haemoglobin oxygenatiuon and haemodynamics. However its use as a method for the assessment of tissue viability following transplantation has recently been explored experimentally in our laboratory. The ability to measure changes in oxygenation and perfusion during harvesting and following transplantation of organs or transfer of free and pedicled flaps is potentially important in reconstructive surgery. We have found that near–infrared spectroscopy is extremely useful in detecting vaso–occlusive events and can accurately and reliably distinguish between arterial, venous or total occlusions. Venous congestion indicated by raised levels of deoxygenated haemoglobin with a concomitant increase in blood volume and the presence and magnitude of reactive hyperaemia are both easily recognizable features by near–infrared spectroscopy. We have shown that near–infrared spectroscopy measurements of venous congestion in kidneys (and other tissues) following prolonged storage correlate with medullary vascular congestion confirmed by angiographical and histological analysis of intrarenal perfusion. Clinically we have shown that flap perfusion can be improved by altering fluid replacement regimes and the addition of ionotropes. Cerebral near–infrared spectroscopy measurements in a liver transplant model showed statistically significant differences within minutes after the anhepatic phase in cerebral perfusion and oxygenation, between animals transplanted with ischaemically damaged livers compared to those isografted with minimally stored livers. Similarly we have found that near–infrared spectroscopy can be used as a monitor to assess the adequacy of fluid or blood replacement in haemorrhagic and hypovolaemic models. We believe that near–infrared spectroscopy provides a sensitive and reliable postoperative method for the assessment of tissue viability following the transfer of free and pedicled flaps and organs.

Published
1997

20. Muonium Emission into Vacuum from Mesoporous Thin Films at Cryogenic Temperatures

Author

K. S. Khaw, Bernardo Barbiellini, K. Kwuida, Laszlo Liszkay, Paolo Crivelli, Thomas Prokscha, Zaher Salman, Klaus Kirch, Aldo Antognini, Elvezio Morenzoni, Florian M. Piegsa, and Andreas Suter

Subjects
Physics, Atomic Physics (physics.atom-ph), 010308 nuclear & particles physics, Muonium, FOS: Physical sciences, General Physics and Astronomy, 01 natural sciences, Physics - Atomic Physics, High Energy Physics - Experiment, 3. Good health, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Thin film, Atomic physics, 010306 general physics, Energy (signal processing)
Abstract

We report on Muonium (Mu) emission into vacuum following {\mu}+ implantation in mesoporous thin SiO2 films. We obtain a yield of Mu into vacuum of (38\pm4)% at 250 K temperature and (20\pm4)% at 100 K for 5 keV {\mu}+ implantation energy. From the implantation energy dependence of the Mu vacuum yield we determine the Mu diffusion constants in these films: D250KMu = (1.6 \pm 0.1) \times 10-4 cm2/s and D100KMu = (4.2\pm0.5)\times10-5 cm2/s. Describing the diffusion process as quantum mechanical tunneling from pore-to-pore, we reproduce the measured temperature dependence T^3/2 of the diffusion constant. We extract a potential barrier of (-0.3 \pm 0.1) eV which is consistent with our computed Mu work-function in SiO2 of [-0.3,-0.9] eV. The high Mu vacuum yield even at low temperatures represents an important step towards next generation Mu spectroscopy experiments., Comment: 5 pages, 5 Figures

Published
2012

22. Closed-loop feedback computer-controlled infusion of phenylephrine for maintaining blood pressure during spinal anaesthesia for caesarean section: a preliminary descriptive study

Author

W D, Ngan Kee, Y H, Tam, K S, Khaw, F F, Ng, L A, Critchley, and M K, Karmakar

Subjects
Adult, Cesarean Section, Blood Pressure, Anesthesia, Spinal, Drug Administration Schedule, Drug Therapy, Computer-Assisted, Feedback, Phenylephrine, Drug Delivery Systems, Pregnancy, Anesthesia, Obstetrical, Feasibility Studies, Humans, Vasoconstrictor Agents, Female, Hypotension, Intraoperative Complications, Algorithms
Abstract

We describe the novel use of a closed-loop feedback computer-controlled infusion of phenylephrine for maintaining blood pressure in 53 patients having spinal anaesthesia for elective caesarean section. A simple on-off algorithm was used that activated an intravenous phenylephrine infusion at 100 microg.min(-1) when systolic blood pressure was less than or equal to baseline and stopped the infusion when systolic blood pressure exceeded baseline. Up to uterine incision, 94.6% of all systolic blood pressure measurements were within the range (baseline +/- 20%). Seven patients (13.2%) had one or more episodes of hypotension (systolic blood pressure80% of baseline) and 23 patients (37.7%) had one or more episodes of hypertension (systolic blood pressure120% of baseline). No patient had nausea or vomiting and in no case was umbilical arterial blood pH7.2. Calculated system performance parameters were comparable with those of previously published closed-loop systems and provide a reference for the potential development and comparison of more advanced algorithms.

Published
2007

23. Effects of high inspired oxygen fraction during elective caesarean section under spinal anaesthesia on maternal and fetal oxygenation and lipid peroxidation

Author

K S, Khaw, C C, Wang, W D, Ngan Kee, C P, Pang, and M S, Rogers

Subjects
Adult, Intraoperative Care, Free Radicals, Cesarean Section, Partial Pressure, Oxygen Inhalation Therapy, Carbon Dioxide, Anesthesia, Spinal, Oxygen, Oxygen Consumption, Double-Blind Method, Pregnancy, Apgar Score, Anesthesia, Obstetrical, Humans, Female, Lipid Peroxidation, Prospective Studies, Maternal-Fetal Exchange
Abstract

Oxygen supplementation is given routinely to parturients undergoing Caesarean section under regional anaesthesia. While the aim is to improve fetal oxygenation, inspiring a high oxygen fraction (FIO2) can also increase free radical activity and lipid peroxidation in both the mother and baby. In this prospective, randomized, double-blind study, we investigated the effect of high inspired oxygen fraction (FIO2) on maternal and fetal oxygenation and oxygen free radical activity in parturients having Caesarean section under spinal anaesthesia.Forty-four healthy parturients were randomized to breathe either 21% (air group) or 60% oxygen (oxygen group) intraoperatively via a ventimask. Maternal arterial blood was collected at 5-min intervals from baseline until delivery, and umbilical arterial and venous blood was collected at delivery. We measured blood gases and the products of lipid peroxidation (8-isoprostane, malondialdehyde (MDA), hydroperoxide (OHP)) and purine metabolites.At delivery, the oxygen group had greater maternal arterial PO2 [mean 30.0 (SD 6.3) vs 14.2 (1.9) kPa; mean difference 15.8 kPa, 95% confidence interval 12.9-18.7 kPa, P0.001] and greater umbilical venous PO2 [4.8 (1.0) vs 4.0 (1.4) kPa; mean difference 0.8 kPa, 95% confidence interval 0.0-1.5 kPa, P=0.04] compared with the air group. Maternal and umbilical plasma concentrations of lipid peroxides (8-isoprostane, MDA, OHP) were greater in the oxygen group than in the air group (P0.05).We conclude that breathing high FIO2 modestly increased fetal oxygenation but caused a concomitant increase in oxygen free radical activity in both mother and fetus.

Published
2002

24. Spinal ropivacaine for cesarean section: a dose-finding study

Author

K S, Khaw, W D, Ngan Kee, E L, Wong, J Y, Liu, and R, Chung

Subjects
Adult, Anesthesia, Epidural, Dose-Response Relationship, Drug, Cesarean Section, Amides, Double-Blind Method, Pregnancy, Anesthesia, Obstetrical, Humans, Female, Ropivacaine, Prospective Studies, Anesthetics, Local, Pain Measurement
Abstract

The dose-response relation for spinal ropivacaine is undetermined, and there are few data available for obstetric patients.In a prospective, randomized, double-blind investigation, the authors studied 72 patients undergoing elective cesarean delivery. An epidural catheter was placed at the L2-L3 vertebral interspace. Lumbar puncture was then performed at the L3-L4 vertebral interspace, and patients were randomized to receive a dose of spinal ropivacaine diluted to 3 ml with normal saline: 10 mg (n = 12), 15 mg (n = 20), 20 mg (n = 20), or 25 mg (n = 20). Sensory changes assessed by ice and pin prick and motor changes assessed by modified Bromage score were recorded at timed intervals. A dose was considered effective if an upper sensory level to pin prick of T7 or above was achieved and epidural supplementation was not required intraoperatively.Anesthesia was successful in 8.3, 45, 70, and 90% of the 10-, 15-, 20-, and 25-mg groups, respectively. A sigmoid dose-response curve and a probit log dose-response plot were obtained, and the authors determined the ED50 (95% confidence interval) to be 16.7 (14.1-18.8) mg and the ED95 (95% confidence interval) to be 26.8 (23.6-34.1) mg. Duration of sensory and motor block and degree of motor block, but not onset of anesthesia, were positively related to dose.The ED50 and estimated ED95 for spinal ropivacaine were 16.7 and 26.8 mg, respectively. Ropivacaine is a suitable agent for spinal anesthesia for cesarean delivery.

Published
2001

26. Randomised double-blind comparison of morphine vs. a morphine-alfentanil combination for patient-controlled analgesia

Author

W D, Ngan Kee, K S, Khaw, and E L, Wong

Subjects
Adult, Analgesics, Opioid, Drug Combinations, Pain, Postoperative, Double-Blind Method, Morphine, Humans, Analgesia, Patient-Controlled, Alfentanil, Pain Measurement
Abstract

In a randomised, double-blind study, we compared a combination of morphine and alfentanil with morphine alone for patient-controlled analgesia (PCA) after Caesarean section under spinal anaesthesia. After surgery, patients were randomly allocated to receive PCA with a bolus dose of either morphine 0.75 mg plus alfentanil 0.125 mg (Group MA, n = 40) or morphine 1.5 mg alone (Group M, n = 37) with a lockout interval of 8 min and no hourly dose limit. Clinical assessments were made in the first 24 h, after which patients completed a written questionnaire. There were no differences between groups in PCA usage or visual analogue scale pain scores measured at 2, 4, 6 and 24 h. There was a low incidence of side-effects in both groups. In the questionnaire, patients in Group MA scored higher compared with Group M when asked to grade speed of onset and effectiveness of analgesia after a PCA bolus; there were no differences in grading for duration of analgesia or overall patient satisfaction. Addition of alfentanil to morphine may have advantages for PCA.

Published
1999

28. Applications of NIRS for Measurements of Tissue Oxygenation and Haemodynamics During Surgery

Author

Cj Green, P. Wall, N. J. Barnett, C. Shurey, S. Simpkin, Maureen S. Thorniley, K. S. Khaw, and J. S. Sinclair

Subjects
medicine.medical_specialty, Cerebral blood volume, Tissue oxygenation, Cerebral oxygenation, business.industry, Internal medicine, Metabolism brain, Cardiology, Respiratory chain, Medicine, Hemodynamics, business
Abstract

Since 1977 when Jobsis described the first use of near infra-red spectroscopy (NIRS) for non-invasive monitoring of changes in cerebral oxyhaemoglobin (O2Hb), deoxyhaemoglobin (HHb) and Caa3 the field has undergone major transformations1,2.

Published
1997

30. Measurement of Cerebral Oxygenation and Haemodynamics During Haemorrhage/Fluid Replacement

Author

Ivan A. Sammut, K. S. Khaw, S. Simpkin, C. Shurey, Maureen S. Thorniley, Cj Green, and E. Balogun

Subjects
medicine.medical_specialty, business.industry, medicine.medical_treatment, Rat model, Hemodynamics, Surgical procedures, Hypoxic cell, Blood loss, Cerebral oxygenation, Internal medicine, medicine, Cardiology, Tissue oxygen, business, Fluid replacement
Abstract

Many major surgical procedures are accompanied by haemorrhage necessitating replacement with either fluid or blood. Despite apparently adequate replacement, tissue oxygen delivery may still be poor, resulting in cellular hypoxia and consequent metabolic dysfunction, which can ultimately lead to multi-organ failure. The overall aim of these investigations was to determine whether near infra-red spectroscopy (NIRS) can be used to measure changes in cerebral oxygenation and haemodynamics in response to controlled blood loss, with and without fluid replacement using a rat model of haemorrhage1-6.

Published
1997

31. Applications of NIRS for measurements of tissue oxygenation and haemodynamics during surgery

Author

M S, Thorniley, S, Simpkin, N J, Barnett, P, Wall, K S, Khaw, C, Shurey, J S, Sinclair, and C J, Green

Subjects
Male, Spectroscopy, Near-Infrared, Swine, Hemodynamics, Brain, Postoperative Hemorrhage, Surgical Flaps, Liver Transplantation, Rats, Oxygen, Disease Models, Animal, Metabolic Diseases, Rats, Inbred Lew, Surgical Procedures, Operative, Animals, Humans, Female, Oximetry, Monitoring, Physiologic
Published
1997

33. Design and performance of SiPM-based readout of PbF 2 crystals for high-rate, precision timing applications

Author

L. K. Gibbons, D.A. Sweigart, K. S. Khaw, P. Kammel, T. D. Van Wechel, G. Venanzoni, W. Gohn, Claudio Ferrari, K. L. Giovanetti, M. W. Smith, A. Fioretti, J. Kaspar, A. Chapelain, M. Iacovacci, T. P. Gorringe, D.A. Peterson, M. A. Huehn, D. W. Hertzog, C. Gabbanini, Dinko Pocanic, S. Mastroianni, A.T. Fienberg, Kaspar, J., Fienberg, A. T., Hertzog, D. W., Huehn, M. A., Kammel, P., Khaw, K. S., Peterson, D. A., Smith, M. W., Van Wechel, T. D., Van Chapelain, D. A., Gibbons, L. K., Sweigart, D. A., Ferrari, C., Fioretti, A., Gabbanini, C., Venanzoni, G., Iacovacci, M., Mastroianni, S., Giovanetti, K., Gohn, W., Gorringe, T., and Pocanic, D.

Subjects
Materials science, Physics - Instrumentation and Detectors, Physics::Instrumentation and Detectors, Photodetector, FOS: Physical sciences, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Optics, Silicon photomultiplier, Front-end electronics for detector readout, 0103 physical sciences, Fermilab, 010306 general physics, Instrumentation, Mathematical Physics, Cherenkov radiation, Calorimeter, 010308 nuclear & particles physics, business.industry, Amplifier, Detector, Instrumentation and Detectors (physics.ins-det), Timing detector, Photon detectors for UV, visible and IR photons (solid-state), business, Storage ring
Abstract

We have developed a custom amplifier board coupled to a large-format 16-channel Hamamatsu silicon photomultiplier device for use as the light sensor for the electromagnetic calorimeters in the Muon g-2 experiment at Fermilab. The calorimeter absorber is an array of lead-fluoride crystals, which produces short-duration Cherenkov light. The detector sits in the high magnetic field of the muon storage ring. The SiPMs selected, and their accompanying custom electronics, must preserve the short pulse shape, have high quantum efficiency, be non-magnetic, exhibit gain stability under varying rate conditions, and cover a fairly large fraction of the crystal exit surface area. We describe an optimized design that employs the new-generation of thru-silicon via devices. The performance is documented in a series of bench and beam tests., In version 2, simplified schematics of the SiPM board was fixed, and high rate test redone

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34. The laser-based gain monitoring system of the calorimeters in the Muon g −2 experiment at Fermilab

Author

S.B. Dabagov, A. Chapelain, S. Di Falco, G. Di Sciascio, M. Incagli, A. Boiano, A. Lusiani, D. Cauz, Dariush Hampai, L. K. Gibbons, J.B. Hempstead, G. M. Piacentino, A. Fioretti, A. Anastasi, E. Bottalico, N. Raha, D. W. Hertzog, G. Venanzoni, A.T. Fienberg, R. Di Stefano, Fabrizio Marignetti, C. Gabbanini, Claudio Ferrari, A. Nath, F. Bedeschi, G. Pauletta, K. S. Khaw, S. Mastroianni, G. Corradi, M. Iacovacci, M. W. Smith, Marin Karuza, A. Gioiosa, S. Donati, S. Miozzi, A. Basti, A. Driutti, M. Sorbara, P. Girotti, D.A. Sweigart, Giovanni Cantatore, P. Di Meo, L. Santi, J. Kaspar, Anastasi, A., Basti, A., Bedeschi, F., Boiano, A., Bottalico, E., Cantatore, G., Cauz, D., Chapelain, A. T., Corradi, G., Dabagov, S., Falco, S. D., Meo, P. D., Sciascio, G. D., Stefano, R. D., Donati, S., Driutti, A., Ferrari, C., Fienberg, A. T., Fioretti, A., Gabbanini, C., Gibbons, L. K., Gioiosa, A., Girotti, P., Hampai, D., Hempstead, J. B., Hertzog, D. W., Iacovacci, M., Incagli, M., Karuza, M., Kaspar, J., Khaw, K. S., Lusiani, A., Marignetti, F., Mastroianni, S., Miozzi, S., Nath, A., Pauletta, G., Piacentino, G. M., Raha, N., Santi, L., Smith, M., Sorbara, M., Sweigart, D. A., Venanzoni, G., Falco, S. Di, Meo, P. Di, Sciascio, G. Di, and Stefano, R. Di

Subjects
sources, Physics - Instrumentation and Detectors, Physics::Instrumentation and Detectors, Detector alignment and calibration methods (lasers, sources, particle-beams), FOS: Physical sciences, 01 natural sciences, 030218 nuclear medicine & medical imaging, law.invention, High Energy Physics - Experiment, Nuclear physics, 03 medical and health sciences, Calorimeters, High Energy Physics - Experiment (hep-ex), 0302 clinical medicine, law, 0103 physical sciences, Calibration, Fermilab, Instrumentation, Mathematical Physics, Physics, Calorimeter, Muon, 010308 nuclear & particles physics, Anomaly (natural sciences), Monitoring system, particle-beams), Instrumentation and Detectors (physics.ins-det), Laser, muon g-2, 3. Good health, Detector alignment and calibration methods (lasers, High Energy Physics::Experiment, Order of magnitude
Abstract

The Muon $g-2$ experiment, E989, is currently taking data at Fermilab with the aim of reducing the experimental error on the muon anomaly by a factor of four and possibly clarifying the current discrepancy with the theoretical prediction. A central component of this four-fold improvement in precision is the laser calibration system of the calorimeters, which has to monitor the gain variations of the photo-sensors with a 0.04\% precision on the short-term ($\sim 1\,$ms). This is about one order of magnitude better than what has ever been achieved for the calibration of a particle physics calorimeter. The system is designed to monitor also long-term gain variations, mostly due to temperature effects, with a precision below the per mille level. This article reviews the design, the implementation and the performance of the Muon $g-2$ laser calibration system, showing how the experimental requirements have been met., 33 pages,24 figures. Matches the published version

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35. Supplementary oxygen for emergency Caesarean section under regional anaesthesia,.

Author

K. S. Khaw, C. C. Wang, W. D. Ngan Kee, W. H. Tam, F. F. Ng, L. A. H. Critchley, and M. S. Rogers

Subjects
*CONDUCTION anesthesia, *CESAREAN section, *EMERGENCY medicine, *HYPERBARIC oxygenation, *RANDOMIZED controlled trials, *PEROXIDATION, *LIPIDS
Abstract

: Background Controversy still exists if the administration of supplementary oxygen to patients having emergency Caesarean section (CS) under regional anaesthesia is beneficial or potentially harmful. Therefore, in a prospective double-blinded study, we randomized patients having emergency CS under regional anaesthesia to receive either air or 60% oxygen until delivery and compared the effects on fetal oxygenation and lipid-peroxidation in the mother and baby. : Methods We recruited 131 women having emergency CS under regional anaesthesia. Either 21% (air group) or 60% oxygen (oxygen group) was administered using a Venturi-type facemask until delivery. We compared the oxygen exposure duration, umbilical arterial (UA) and venous (UV) blood gases and oxygen content, and plasma concentration of 8-isoprostane. Subanalysis was performed according to whether or not fetal compromise was considered present. : Results Data from 125 patients were analysed. For the oxygen group vs the air group, there were greater values for UA Po2 [mean 2.2 (sd 0.5) vs 1.9 (0.6) kPa, P=0.01], UA O2 content [6.6 (2.5) vs 4.9 (2.8) ml dl−1, P=0.006], UV Po2 [3.8 (0.8) vs 3.2 (0.8) kPa, P<0.0001], and UV O2 content [12.9 (3.5) vs 10.4 (3.8) ml dl−1, P=0.001]. There was no difference between the groups in maternal, UA, or UV 8-isoprostane concentration. Apgar scores and UA pH were similar between the groups. Similar changes were observed regardless of whether fetal compromise was considered present (n=37) or not (n=88). : Conclusions Breathing 60% oxygen during emergency CS under regional anaesthesia increased fetal oxygenation with no associated increase in lipid-peroxidation in the mother or fetus. [ABSTRACT FROM AUTHOR]

Published
2009
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