Author: "Grabmüller S" / Publication Type: Reports - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Grabmüller S"' showing total 34 results

Start Over Author "Grabmüller S" Publication Type Reports

34 results on '"Grabmüller S"'

1. First measurement of the Sivers asymmetry for gluons from SIDIS data

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Roskot, M., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. It was extracted from measurements of the azimuthal asymmetry of hadrons produced in semi-inclusive deep inelastic scattering of leptons off transversely polarised nucleon targets, and it turned out to be non-zero for quarks. In this letter the evaluation of the Sivers asymmetry for gluons in the same process is presented. The analysis method is based on a Monte Carlo simulation that includes three hard processes: photon-gluon fusion, QCD Compton scattering and leading-order virtual-photon absorption process. The Sivers asymmetries of the three processes are simultaneously extracted using the LEPTO event generator and a neural network approach. The method is applied to samples of events containing at least two hadrons with large transverse momentum from the COMPASS data taken with a 160 GeV/$c$ muon beam scattered off transversely polarised deuterons and protons. With a significance of more than two standard deviations a negative value is obtained for the gluon Sivers asymmetry. The result of a similar analysis for a Collins-like asymmetry for gluons is consistent with zero., Comment: 18 pages, 8 figures
Published: 2017
Full Text: View/download PDF

2. Final COMPASS results on the deuteron spin-dependent structure function $g_1^{\rm d}$ and the Bjorken sum rule

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., Windmolders, R., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment
Abstract: Final results are presented from the inclusive measurement of deep-inelastic polarised-muon scattering on longitudinally polarised deuterons using a $^6$LiD target. The data were taken at $160~{\rm GeV}$ beam energy and the results are shown for the kinematic range $1~({\rm GeV}/c)^2 < Q^2 < 100~({\rm GeV}/c)^2$ in photon virtuality, $0.004 4~{\rm GeV}/c^2$ in the mass of the hadronic final state. The deuteron double-spin asymmetry $A_1^{\rm d}$ and the deuteron longitudinal-spin structure function $g_1^{\rm d}$ are presented in bins of $x$ and $Q^2$. Towards lowest accessible values of $x$, $g_1^{\rm d}$ decreases and becomes consistent with zero within uncertainties. The presented final $g_1^{\rm d}$ values together with the recently published final $g_1^{\rm p}$ values of COMPASS are used to again evaluate the Bjorken sum rule and perform the QCD fit to the $g_1$ world data at next-to-leading order of the strong coupling constant. In both cases, changes in central values of the resulting numbers are well within statistical uncertainties. The flavour-singlet axial charge $a_0$, {which is identified in the $\overline{\rm MS}$ renormalisation scheme with the total contribution of quark helicities to the nucleon spin}, is extracted from only the COMPASS deuteron data with negligible extrapolation uncertainty: $a_0 (Q^2 = 3~({\rm GeV}/c)^2) = 0.32 \pm 0.02_{\rm stat} \pm0.04_{\rm syst} \pm 0.05_{\rm evol}$. Together with the recent results on the proton spin structure function $g_1^{\rm p}$, the results on $g_1^{\rm d}$ constitute the COMPASS legacy on the measurements of $g_1$ through inclusive spin-dependent deep inelastic scattering., Comment: 16 pages, 6 figures
Published: 2016
Full Text: View/download PDF

3. Sivers asymmetry extracted in SIDIS at the hard scale of the Drell-Yan process at COMPASS

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Proton transverse-spin azimuthal asymmetries are extracted from the COMPASS 2010 semi-inclusive hadron measurements in deep inelastic muon-nucleon scattering in those four regions of the photon virtuality $Q^2$, which correspond to the four regions of the di-muon mass $\sqrt{Q^2}$ used in the ongoing analysis of the COMPASS Drell-Yan measurements. This allows for a future direct comparison of the nucleon transverse-momentum-dependent parton distribution functions extracted from these two alternative measurements. Various two-dimensional kinematic dependences are presented for the azimuthal asymmetries induced by the Sivers transverse-momentum-dependent parton distribution function. The integrated Sivers asymmetries are found to be positive with an accuracy that appears to be sufficient to test the sign change of the Sivers function predicted by Quantum Chromodynamics., Comment: 13 pages, 6 figures
Published: 2016
Full Text: View/download PDF

4. Azimuthal asymmetries of charged hadrons produced in high-energy muon scattering off longitudinally polarised deuterons

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Single hadron azimuthal asymmetries of positive and negative hadrons produced in muon semi-inclusive deep inelastic scattering off longitudinally polarised deuterons are determined using the 2006 COMPASS data and also combined all deuteron COMPASS data. For each hadron charge, the dependence of the azimuthal asymmetry on the hadron azimuthal angle $\phi$ is obtained by means of a five-parameter fitting function that besides a $\phi$-independent term includes four modulations predicted by theory: $\sin\phi$, $\sin 2 \phi$, $\sin 3\phi$ and $\cos\phi$. The amplitudes of the five terms have been extracted, first, for the hadrons in the whole available kinematic region. In further fits, performed for hadrons from a restricted kinematic region, the $\phi$-dependence is determined as a function of one of three variables (Bjorken-$x$, fractional energy of virtual photon taken by the outgoing hadron and hadron transverse momentum), while disregarding the others. Except the $\phi$-independent term, all the modulation amplitudes are very small, and no clear kinematic dependence could be observed within experimental uncertainties., Comment: 15 pages, 5 figures
Published: 2016
Full Text: View/download PDF

5. Multiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target

Author: Adolph, C., Agarwala, J., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Capozza, L., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joeorg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., Windmolders, R., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Precise measurements of charged-kaon multiplicities in deep inelastic scattering were performed. The results are presented in three-dimensional bins of the Bjorken scaling variable x, the relative virtual-photon energy y, and the fraction z of the virtual-photon energy carried by the produced hadron. The data were obtained by the COMPASS Collaboration by scattering 160 GeV muons off an isoscalar 6 LiD target. They cover the kinematic domain 1 (GeV/c)2 < Q2 < 60 (GeV/c)^2 in the photon virtuality, 0.004 < x < 0.4, 0.1 < y < 0.7, 0.20 < z < 0.85, and W > 5 GeV/c^2 in the invariant mass of the hadronic system. The results from the sum of the z-integrated K+ and K- multiplicities at high x point to a value of the non-strange quark fragmentation function larger than obtained by the earlier DSS fit., Comment: 10 pages, 9 figures
Published: 2016
Full Text: View/download PDF

6. Exclusive $\omega$ meson muoproduction on transversely polarised protons

Author: Adolph, C., Agarwala, J., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Heitz, R., Herrmann, F., Hinterberger, F., Horikawa, N., dHose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Michigami, T., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Montuenga, P., Nagaytsev, A., Nerling, F., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Seder, E., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Steffen, D., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Exclusive production of $\omega$ mesons was studied at the COMPASS experiment by scattering $160~\mathrm{GeV}/\mathit{c}$ muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured in the range of photon virtuality $1~(\mathrm{GeV}/\mathit{c})^2 < Q^2 < 10~(\mathrm{GeV}/\mathit{c})^2$, Bjorken scaling variable $0.003 < x_{\mathit{Bj}} < 0.3$ and transverse momentum squared of the $\omega$ meson $0.05~(\mathrm{GeV}/\mathit{c})^2 < p_{T}^{2} < 0.5~(\mathrm{GeV}/\mathit{c})^2$. The measured asymmetries are sensitive to the nucleon helicity-flip Generalised Parton Distributions (GPD) $E$ that are related to the orbital angular momentum of quarks, the chiral-odd GPDs $H_{T}$ that are related to the transversity Parton Distribution Functions, and the sign of the $\pi\omega$ transition form factor. The results are compared to recent calculations of a GPD-based model., Comment: 23 pages, 9 figures
Published: 2016
Full Text: View/download PDF

7. Multiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target

Author: Adolph, C., Agarwala, J., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Capozza, L., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Heitz, R., Herrmann, F., Hinterberger, F., Horikawa, N., dHose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kuhn, R., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, W., Michigami, T., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Montuenga, P., Nagaytsev, A., Nerling, F., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Seder, E., Selyunin, A., Shevchenko, O. Yu., Steffen, D., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Weisrock, T., Wilfert, M., Windmolders, R., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Multiplicities of charged pions and unidentified hadrons produced in deep-inelastic scattering were measured in bins of the Bjorken scaling variable $x$, the relative virtual-photon energy $y$ and the relative hadron energy $z$. Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam and an isoscalar target ($^6$LiD). They cover the kinematic domain in the photon virtuality $Q^2$ > 1(GeV/c$)^2$, $0.004 < x < 0.4$, $0.2 < z < 0.85$ and $0.1 < y < 0.7$. In addition, a leading-order pQCD analysis was performed using the pion multiplicity results to extract quark fragmentation functions.
Published: 2016
Full Text: View/download PDF

8. Leading-order determination of the gluon polarisation from semi-inclusive deep inelastic scattering data

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Heitz, R., Herrmann, F., Hinterberger, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, W., Michigami, T., Mikhailov, Yu. V., Mikhasenko, M., Miyachi, Y., Montuenga, P., Nagaytsev, A., Nerling, F., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Seder, E., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Using a novel analysis technique, the gluon polarisation in the nucleon is re-evaluated using the longitudinal double-spin asymmetry measured in the cross section of semi-inclusive single-hadron muoproduction with photon virtuality $Q^2>1~({\rm GeV}/c)^2$. The data were obtained by the COMPASS experiment at CERN using a 160 GeV/$c$ polarised muon beam impinging on a polarised $^6$LiD target. By analysing the full range in hadron transverse momentum $p_{\rm T}$, the different $p_{\rm T}$-dependences of the underlying processes are separated using a neural-network approach. In the absence of pQCD calculations at next-to-leading order in the selected kinematic domain, the gluon polarisation $\Delta g/g$ is evaluated at leading order in pQCD at a hard scale of $\mu^2= \langle Q^2 \rangle = 3 ({\rm GeV}/c)^2$. It is determined in three intervals of the nucleon momentum fraction carried by gluons, $x_{\rm g}$, covering the range $0.04 \!<\! x_{ \rm g}\! <\! 0.28$~ and does not exhibit a significant dependence on $x_{\rm g}$. The average over the three intervals, $\langle \Delta g/g \rangle = 0.113 \pm 0.038_{\rm (stat.)}\pm 0.036_{\rm (syst.)}$ at $\langle x_{\rm g} \rangle \approx 0.10$, suggests that the gluon polarisation is positive in the measured $x_{\rm g}$ range., Comment: 14 pages, 6 figures
Published: 2015

9. Longitudinal double spin asymmetries in single hadron quasi-real photoproduction at high $p_T$

Author: COMPASS Collaboration, Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badełek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Büchele, M., Burtin, E., Chang, W. -C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Dünnweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmüller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Joosten, R., Jörg, P., Kabuß, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Krämer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kuchinski, N., Kuhn, R., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matoušek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Montuenga, P., Nagaytsev, A., Nerling, F., Neyret, D., Nikolaenko, V. I., Nový, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pešek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schönning, K., Schopferer, S., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: We measured the longitudinal double spin asymmetries $A_{LL}$ for single hadron muo-production off protons and deuterons at photon virtuality $Q^2$ < 1(GeV/$\it c$)$^2$ for transverse hadron momenta $p_T$ in the range 0.7 GeV/$\it c$ to 4 GeV/$\it c$ . They were determined using COMPASS data taken with a polarised muon beam of 160 GeV/$\it c$ or 200 GeV/$\it c$ impinging on polarised $\mathrm{{}^6LiD}$ or $\mathrm{NH_3}$ targets. The experimental asymmetries are compared to next-to-leading order pQCD calculations, and are sensitive to the gluon polarisation $\Delta G$ inside the nucleon in the range of the nucleon momentum fraction carried by gluons $0.05 < x_g < 0.2$.
Published: 2015

10. Resonance Production and $\pi\pi$ S-wave in $\pi^- + p \rightarrow \pi^- \pi^- \pi^+ + p_{recoil}$ at 190 GeV/c

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badełek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Büchele, M., Burtin, E., Chang, W. -C., Chiosso, M., Choi, I., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Dünnweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmüller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Joosten, R., Jörg, P., Kabuß, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Krämer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matoušek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Montuenga, P., Nagaytsev, A., Nerling, F., Neyret, D., Nikolaenko, V. I., Nový, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pešek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schlüter, T., Schmidt, K., Schmieden, H., Schönning, K., Schopferer, S., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The COMPASS collaboration has collected the currently largest data set on diffractively produced $\pi^-\pi^-\pi^+$ final states using a negative pion beam of 190 GeV/c momentum impinging on a stationary proton target. This data set allows for a systematic partial-wave analysis in 100 bins of three-pion mass, $0.5 < m_{3\pi} < 2.5$ GeV/c$^2$ , and in 11 bins of the reduced four-momentum transfer squared, $0.1 < t < 1.0$ (GeV/c)$^2$ . This two-dimensional analysis offers sensitivity to genuine one-step resonance production, i.e. the production of a state followed by its decay, as well as to more complex dynamical effects in nonresonant $3\pi$ production. In this paper, we present detailed studies on selected $3\pi$ partial waves with $J^{PC} = 0^{-+}$, $1^{++}$, $2^{-+}$, $2^{++}$, and $4^{++}$. In these waves, we observe the well-known ground-state mesons as well as a new narrow axial-vector meson $a_1(1420)$ decaying into $f_0(980) \pi$. In addition, we present the results of a novel method to extract the amplitude of the $\pi^-\pi^+$ subsystem with $I^{G}J^{PC} = 0^+ 0^{++}$ in various partial waves from the $\pi^-\pi^-\pi^+$ data. Evidence is found for correlation of the $f_0(980)$ and $f_0(1500)$ appearing as intermediate $\pi^- \pi^+$ isobars in the decay of the known $\pi(1800)$ and $\pi_2(1880)$., Comment: 96 pages
Published: 2015
Full Text: View/download PDF

11. Interplay among transversity induced asymmetries in hadron leptoproduction

Author: Compass Collaboration, Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Büchele, M., Burtin, E., Chang, W. -C., Chiosso, M., Choi, I., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., d'Hose, N., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmüller, S., Grasso, A., Grosse-Perdekamp, M., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Horikawa, N., Hsieh, C. -Yu, Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jörg, P., Joosten, R., Kabuß, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Krämer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Montuenga, P., Nagaytsev, A., Nerling, F., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesaro, G., Pesek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schönning, K., Schopferer, S., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Weisrock, T., Wilfert, M., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows to establish quantitative relationships among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process., Comment: 6 figures
Published: 2015
Full Text: View/download PDF

12. The Spin Structure Function $g_1^{\rm p}$ of the Proton and a Test of the Bjorken Sum Rule

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Azevedo, C., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, G. R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chang, W. -C., Chiosso, M., Choi, I., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmüller, S., Grasso, A., Grosse-Perdekamp, M., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Horikawa, N., d'Hose, N., Hsieh, C. -Yu, Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jörg, P., Joosten, R., Kabuß, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Weisrock, T., Wilfert, M., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: New results for the double spin asymmetry $A_1^{\rm p}$ and the proton longitudinal spin structure function $g_1^{\rm p}$ are presented. They were obtained by the COMPASS collaboration using polarised 200 GeV muons scattered off a longitudinally polarised NH$_3$ target. The data were collected in 2011 and complement those recorded in 2007 at 160\,GeV, in particular at lower values of $x$. They improve the statistical precision of $g_1^{\rm p}(x)$ by about a factor of two in the region $x\lesssim 0.02$. A next-to-leading order QCD fit to the $g_1$ world data is performed. It leads to a new determination of the quark spin contribution to the nucleon spin, $\Delta \Sigma$ ranging from 0.26 to 0.36, and to a re-evaluation of the first moment of $g_1^{\rm p}$. The uncertainty of $\Delta \Sigma$ is mostly due to the large uncertainty in the present determinations of the gluon helicity distribution. A new evaluation of the Bjorken sum rule based on the COMPASS results for the non-singlet structure function $g_1^{\rm NS}(x,Q^2)$ yields as ratio of the axial and vector coupling constants $|g_{\rm A}/g_{\rm V}| = 1.22 \pm 0.05~({\rm stat.}) \pm 0.10~({\rm syst.})$, which validates the sum rule to an accuracy of about 9\%., Comment: 19 pages, 8 figures and tables
Published: 2015
Full Text: View/download PDF

13. Observation of a new narrow axial-vector meson $a_1(1420)$

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Azevedo, C., Badelek, B., Balestra, F., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Chang, W. -C., Chiosso, M., Choi, I., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duennweber, W, Duic, V., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Grosse-Perdekamp, M., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., von Harrach, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Horikawa, N., d'Hose, N., Hsieh, C. -Yu, Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schlueter, T., Selyunin, A., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Wallner, S., Weisrock, T., Wilfert, M., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment
Abstract: The COMPASS collaboration at CERN has measured diffractive dissociation of 190 GeV/$c$ pions into the $\pi^-\pi^-\pi^+$ final state using a stationary hydrogen target. A partial-wave analysis (PWA) was performed in bins of $3\pi$ mass and four-momentum transfer using the isobar model and the so far largest PWA model consisting of 88 waves. A narrow $J^{PC} = 1^{++}$ signal is observed in the $f_0(980)\,\pi$ channel. We present a resonance-model study of a subset of the spin-density matrix selecting $3\pi$ states with $J^{PC} = 2^{++}$ and $4^{++}$ decaying into $\rho(770)\,\pi$ and with $J^{PC} = 1^{++}$ decaying into $f_0(980)\,\pi$. We identify a new $a_1$ meson with mass $(1414^{+15}_{-13})$ MeV/$c^2$ and width $(153^{+8}_{-23})$ MeV/$c^2$. Within the final states investigated in our analysis, we observe the new $a_1(1420)$ decaying only into $f_0(980)\,\pi$, suggesting its exotic nature., Comment: 8 pages, 1 figure
Published: 2015
Full Text: View/download PDF

14. The COMPASS Setup for Physics with Hadron Beams

Author: Abbon, Ph., Adolph, C., Akhunzyanov, R., Alexandrov, Yu., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bielert, E. R., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Ciliberti, P., Chiosso, M., Chung, S. U., Cicuttin, A., Colantoni, M., Cotte, D., Crespo, M. L., Curiel, Q., Dafni, T., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Desforge, D., Dinkelbach, A. M., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Durand, D., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gatignon, L., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giganon, A., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Gregori, M., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kuhn, R., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Marroncle, J., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Menon, G., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Moinester, M. A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Pesaro, G., Pesaro, V., Peshekhonov, D. V., Pires, C., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Reymond, J-M., Rocco, E., Rossiyskaya, N. S., Rousse, J. -Y., Ryabchikov, D. I., Rychter, A., Samartsev, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Tskhay, V., Uhl, S., Uman, I., Virius, M., Wang, L., Weisrock, T., Weitzel, Q., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract: The main characteristics of the COMPASS experimental setup for physics with hadron beams are described. This setup was designed to perform exclusive measurements of processes with several charged and/or neutral particles in the final state. Making use of a large part of the apparatus that was previously built for spin structure studies with a muon beam, it also features a new target system as well as new or upgraded detectors. The hadron setup is able to operate at the high incident hadron flux available at CERN. It is characterised by large angular and momentum coverages, large and nearly flat acceptances, and good two and three-particle mass resolutions. In 2008 and 2009 it was successfully used with positive and negative hadron beams and with liquid hydrogen and solid nuclear targets. This article describes the new and upgraded detectors and auxiliary equipment, outlines the reconstruction procedures used, and summarises the general performance of the setup., Comment: 91 pages, 101 figures and 7 tables
Published: 2014
Full Text: View/download PDF

15. Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised proton

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bielert, E. R., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment
Abstract: Measurements of the Collins and Sivers asymmetries for charged pions and charged and neutral kaons produced in semi-inclusive deep-inelastic scattering of high energy muons off transversely polarised protons are presented. The results were obtained using all the available COMPASS proton data, which were taken in the years 2007 and 2010. The Collins asymmetries exhibit in the valence region a non-zero signal for pions and there are hints of non-zero signal also for kaons. The Sivers asymmetries are found to be positive for positive pions and kaons and compatible with zero otherwise., Comment: 15 pages, 13 figures and 1 table
Published: 2014
Full Text: View/download PDF

16. Odd and Even Partial Waves of $\eta\pi^-$ and $\eta'\pi^-$ in $\pi^-p\to\eta^{(\prime)}\pi^-p$ at $191\,\textrm{GeV}/c$

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bielert, E. R., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Exclusive production of $\eta\pi^-$ and $\eta'\pi^-$ has been studied with a $191\,\textrm{GeV}/c$ $\pi^-$ beam impinging on a hydrogen target at COMPASS (CERN). Partial-wave analyses reveal different odd/even angular momentum ($L$) characteristics in the inspected invariant mass range up to $3\,\textrm{GeV}/c^2$. A striking similarity between the two systems is observed for the $L=2,4,6$ intensities (scaled by kinematical factors) and the relative phases. The known resonances $a_2(1320)$ and $a_4(2040)$ are in line with this similarity. In contrast, a strong enhancement of $\eta'\pi^-$ over $\eta\pi^-$ is found for the $L=1,3,5$ waves, which carry non-$q\bar q$ quantum numbers. The $L=1$ intensity peaks at $1.7\,\textrm{GeV}/c^2$ in $\eta'\pi^-$ and at $1.4\,\textrm{GeV}/c^2$ in $\eta\pi^-$, the corresponding phase motions with respect to $L=2$ are different., Comment: 16 pages, 5 figures and 1 table
Published: 2014
Full Text: View/download PDF

17. Search for exclusive photoproduction of Z$_c^{\pm}$(3900) at COMPASS

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bielert, E. R., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Peshekhonov, D. V., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment
Abstract: A search for the exclusive production of the $Z_c^{\pm}(3900)$ hadron by virtual photons has been performed in the channel $Z_c^{\pm}(3900)\rightarrow J/\psi \pi^{\pm}$. The data cover the range from 7 GeV to 19 GeV in the centre-of-mass energy of the photon-nucleon system. The full set of the COMPASS data set collected with a muon beam between 2002 and 2011 has been used. An upper limit for the ratio $BR(Z_c^{\pm}(3900)\rightarrow J/\psi \pi^{\pm} )\times \sigma_{ \gamma~N \rightarrow Z_c^{\pm}(3900)~ N} /\sigma_{\gamma~N \rightarrow J/\psi~ N}$ of $3.7\times10^{-3}$ has been established at the confidence level of 90%., Comment: 8 pages, 3 figures, 1 table
Published: 2014
Full Text: View/download PDF

18. Spin alignment and violation of the OZI rule in exclusive $\omega$ and $\phi$ production in pp collisions

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger, r. M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Grussenmeyer, T., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, h., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, u., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, u. A., Kisselev, u., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, u. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Peshekhonov, D., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Exclusive production of the isoscalar vector mesons $\omega$ and $\phi$ is measured with a 190 GeV$/c$ proton beam impinging on a liquid hydrogen target. Cross section ratios are determined in three intervals of the Feynman variable $x_{F}$ of the fast proton. A significant violation of the OZI rule is found, confirming earlier findings. Its kinematic dependence on $x_{F}$ and on the invariant mass $M_{p\mathrm{V}}$ of the system formed by fast proton $p_\mathrm{fast}$ and vector meson $V$ is discussed in terms of diffractive production of $p_\mathrm{fast}V$ resonances in competition with central production. The measurement of the spin density matrix element $\rho_{00}$ of the vector mesons in different selected reference frames provides another handle to distinguish the contributions of these two major reaction types. Again, dependences of the alignment on $x_{F}$ and on $M_{p\mathrm{V}}$ are found. Most of the observations can be traced back to the existence of several excited baryon states contributing to $\omega$ production which are absent in the case of the $\phi$ meson. Removing the low-mass $M_{p\mathrm{V}}$ resonant region, the OZI rule is found to be violated by a factor of eight, independently of $x_\mathrm{F}$., Comment: 23 pages, 13 figures and 5 tables
Published: 2014
Full Text: View/download PDF

19. Measurement of the charged-pion polarisability

Author: Adolph, C., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Colantoni, M., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dinkelbach, A. M., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger, M. jr., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Grussenmeyer, T., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kuhn, R., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Moinester, M. A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Peshekhonov, D., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Rocco, E., Rossiyskaya, N. S., Ryabchikov, D. I., Rychter, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: The COMPASS collaboration at CERN has investigated pion Compton scattering, $\pi^-\gamma\rightarrow \pi^-\gamma$, at centre-of-mass energy below 3.5 pion masses. The process is embedded in the reaction $\pi^-\mathrm{Ni}\rightarrow\pi^-\gamma\;\mathrm{Ni}$, which is initiated by 190\,GeV pions impinging on a nickel target. The exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, $Q^2<0.0015$\,(GeV/$c$)$^2$. From a sample of 63\,000 events the pion electric polarisability is determined to be $\alpha_\pi\ =\ (\,2.0\ \pm\ 0.6_{\mbox{\scriptsize stat}}\ \pm\ 0.7_{\mbox{\scriptsize syst}}\,) \times 10^{-4}\,\mbox{fm}^3$ under the assumption $\alpha_\pi=-\beta_\pi$, which relates the electric and magnetic dipole polarisabilities. It is the most precise measurement of this fundamental low-energy parameter of strong interaction, that has been addressed since long by various methods with conflicting outcomes. While this result is in tension with previous dedicated measurements, it is found in agreement with the expectation from chiral perturbation theory. An additional measurement replacing pions by muons, for which the cross-section behavior is unambigiously known, was performed for an independent estimate of the systematic uncertainty., Comment: Published version: 9 pages, 3 figures, 1 table
Published: 2014
Full Text: View/download PDF

20. Measurement of radiative widths of $a_2(1320)$ and $\pi_2(1670)$

Author: Adolph, C., Akhunzyanov, R., Alekseev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger~jr., M., Fischer, H., Franco, C., du~Fresne~von~Hohenesche, N., Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kral, Z., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Orlov, I., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Pesek, M., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Reicherz, G., Rocco, E., Rychter, A., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter~Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vondra, J., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., and Ziembicki., M.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The COMPASS Collaboration at CERN has investigated the reaction $\pi^- \gamma \rightarrow \pi^-\pi^-\pi^+$ embedded in the Primakoff reaction of $190~\textrm{GeV}$ pions scattering in the Coulomb field of a lead target, $\pi^- \text{Pb} \rightarrow \pi^-\pi^-\pi^+ \text{Pb}$. Exchange of quasi-real photons is selected by isolating the sharp Coulomb peak observed at momentum transfer below $0.001~(\text{GeV}/c)^2$. Using a partial-wave analysis the amplitudes and relative phases of the $a_2(1320)$ and $\pi_2(1670)$ mesons have been extracted, and the Coulomb and the diffractive contributions have been disentangled. Measuring absolute production cross sections we have determined the radiative width of the $a_2(1320)$ to be $\Gamma_0(a_2(1320) \rightarrow \pi\gamma) = (358 \pm 6_{\textrm{stat}} \pm 42_{\textrm{syst}})~\textrm{keV}$. As the first measurement, $\Gamma_0(\pi_2(1670) \rightarrow \pi\gamma) = (181 \pm 11_{\textrm{stat}} \pm 27_{\textrm{syst}})~\textrm{keV} \cdot (\textrm{BR}^{\textrm{PDG}}_{f_2 \pi}/\textrm{BR}_{f_2 \pi})$ is obtained for the radiative width of the $\pi_2(1670)$, where in this analysis the branching ratio $\textrm{BR}^{\textrm{PDG}}_{f_2 \pi}=0.56$ has been used. We compare these values to previous measurements and theoretical predictions., Comment: 27 pages, 12 figures and 3 tables
Published: 2014
Full Text: View/download PDF

21. A high-statistics measurement of transverse spin effects in dihadron production from muon-proton semi-inclusive deep-inelastic scattering

Author: Adolph, C., Akhunzyanov, R., Alekseev, M. G., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kral, Z., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Orlov, I., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Pesek, M., Peshekhonov, D., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Reicherz, G., Rocco, E., Rodionov, V., Rondio, E., Rychter, A., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabeleski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vondra, J., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: A measurement of the azimuthal asymmetry in dihadron production in deep-inelastic scattering of muons on transversely polarised proton (NH$_{3}$) targets are presented. They provide independent access to the transversity distribution functions through the measurement of the Collins asymmetry in single hadron production. The data were taken in the year $2010$ with the COMPASS spectrometer using a $160\,\mbox{GeV}/c$ muon beam of the CERN SPS, increasing by a factor of about three the available statistics of the previously published data taken in the year $2007$. The measured sizeable asymmetry is in good agreement with the published data. An approximate equality of the Collins asymmetry and the dihadron asymmetry is observed, suggesting a common physical mechanism in the underlying fragmentation., Comment: 14 pages, 8 figures
Published: 2014
Full Text: View/download PDF

22. Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons

Author: Adolph, C., Akhunzyanov, R., Alekseev, M. G., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Andrieux, V., Anosov, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Beck, R., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bodlak, M., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Gorzellik, M., Grabmueller, S., Grasso, A., Grube, B., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hahne, D., Hashimoto, R., Heinsius, F. H., Herrmann, F., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joerg, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kral, Z., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Orlov, I., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Pesek, M., Peshekhonov, D., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Reicherz, G., Rocco, E., Rodionov, V., Rondio, E., Rychter, A., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Szabeleski, A., Szameitat, T., Sznajder, P., Takekawa, S., ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vondra, J., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., and Ziembicki, M.
Subjects: High Energy Physics - Experiment
Abstract: Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS muon beam at $160$ GeV/c and a $^6$LiD target. The amplitudes of the three azimuthal modulations $\cos\phi_h$, $\cos2\phi_h$ and $\sin\phi_h$ were obtained binning the data separately in each of the relevant kinematic variables $x$, $z$ or $p_T^{\,h}$ and binning in a three-dimensional grid of these three variables. The amplitudes of the $\cos \phi_h$ and $\cos 2\phi_h$ modulations show strong kinematic dependencies both for positive and negative hadrons., Comment: 33 pages, 15 figures and 10 pages
Published: 2014
Full Text: View/download PDF

23. Transverse target spin asymmetries in exclusive $\rho^0$ muoproduction

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Andrieux, V., Austregesilo, A., Badellek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hahne, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Marchand, C., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Morreale, A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Pesek, M., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Reicherz, G., Rocco, E., Rodionov, V., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmitt, L., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vondra, J., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Exclusive production of $\rho^0$ mesons was studied at the COMPASS experiment by scattering 160 GeV/$c$ muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured as a function of $Q^2$, $x_{Bj}$, or $p_{T}^{2}$. The $\sin \phi_S$ asymmetry is found to be $-0.019 \pm 0.008(stat.) \pm 0.003(syst.)$. All other asymmetries are also found to be of small magnitude and consistent with zero within experimental uncertainties. Very recent calculations using a GPD-based model agree well with the present results. The data is interpreted as evidence for the existence of chiral-odd, transverse generalized parton distributions., Comment: 14 pages, two tables, 5 figures, bibliography updated
Published: 2013
Full Text: View/download PDF

24. Hadron Transverse Momentum Distributions in Muon Deep Inelastic Scattering at 160 GeV/$c$

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Andrieux, V., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Morreale, A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Reicherz, G., Rocco, E., Rodionov, V., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmitt, L., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wiślicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Multiplicities of charged hadrons produced in deep inelastic muon scattering off a $^6$LiD target have been measured as a function of the DIS variables $x_{Bj}$, $Q^2$, $W^2$ and the final state hadron variables $p_T$ and $z$. The $p_T^2$ distributions are fitted with a single exponential function at low values of $p_T^2$ to determine the dependence of $\langle p_T^2 \rangle$ on $x_{Bj}$, $Q^2$, $W^2$ and $z$. The $z$-dependence of $\langle p_T^2 \rangle$ is shown to be a potential tool to extract the average intrinsic transverse momentum squared of partons, $\langle k_{\perp}^2 \rangle$, as a function of $x_{Bj}$ and $Q^2$ in a leading order QCD parton model., Comment: 18 pages, 13 figures and 3 tables
Published: 2013
Full Text: View/download PDF

25. Study of \Sigma(1385) and \Xi(1321) hyperon and antihyperon production in deep inelastic muon scattering

Author: Adolph, C., Alekseev, M., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Morreale, A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Reicherz, G., Rocco, E., Rodionov, V., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmitt, L., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Large samples of \Lambda, \Sigma(1385) and \Xi(1321) hyperons produced in deep-inelastic muon scattering off a ^6LiD target were collected with the COMPASS experimental setup at CERN. The relative yields of \Sigma(1385)^+, \Sigma(1385)^-, \bar{\Sigma}(1385)^-, \bar{\Sigma}(1385)^+, \Xi(1321)^-, and \bar{\Xi}(1321)^+ hyperons decaying into \Lambda(\bar{\Lambda})\pi were measured. The heavy hyperon to \Lambda and heavy antihyperon to \bar{\Lambda} yield ratios were found to be in the range 3.8% to 5.6% with a relative uncertainty of about 10%. They were used to tune the parameters relevant for strange particle production of the LEPTO Monte Carlo generator., Comment: 13 pages, 4 figures and 3 tables, 1 Appendix with 3 figures. Version accepted by the Editor
Published: 2013
Full Text: View/download PDF

26. Leading and Next-to-Leading Order Gluon Polarisation in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger Jr, M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Horikawa, N., Hoeppner, Ch., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Liska, T., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmitt, L., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlev, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: The gluon polarisation in the nucleon was measured using open charm production by scattering 160 GeV/c polarised muons off longitudinally polarised protons or deuterons. The data were taken by the COMPASS collaboration between 2002 and 2007. A detailed account is given of the analysis method that includes the application of neural networks. Several decay channels of D^0 mesons are investigated. Longitudinal spin asymmetries of the D meson production cross-sections are extracted in bins of D^0 transverse momentum and energy. At leading order QCD accuracy the average gluon polarisation is determined as (Delta g/G)^LO=-0.06 +/- 0.21 (stat.) +/- 0.08 (syst.) at the scale ~13 (GeV/c)^2 and an average gluon momentum fraction ~ 0.11. For the first time, the average gluon polarisation is also obtained at next-to-leading order QCD accuracy as (Delta g/G)^NLO = -0.13 +/- 0.15 (stat.) +/- 0.15 (syst.) at the scale ~ 13 (\GeV/c)^2 and ~ 0.20., Comment: 35 pages, 13 figures and 13 tables
Published: 2012
Full Text: View/download PDF

27. D* and D Meson Production in Muon Nucleon Interactions at 160 GeV/c

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger Jr, M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Horikawa, N., Hoeppner, Ch., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Liska, T., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmitt, L., Schmieden, H., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlev, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: The production of D* and D mesons in inelastic scattering of 160 GeV/c muons off a ^6LiD target has been investigated with the COMPASS spectrometer at CERN for 0.003 (GeV/c)^2 < Q^2 < 10 (GeV/c)^2 and 3x10^-5< x_Bj < 0.1. The study is based on 8100 events where a D^0 or anti D^0 is detected subsequently to a D*+ or D*- decay, and on 34000 events, where only a D^0 or anti D^0 is detected. Kinematic distributions of D*, D and K*_2 are given as a function of their energy E, transverse momentum p_T, energy fraction z, and of the virtual photon variables nu, Q^2 and x_Bj. Semi-inclusive differential D* production cross-sections are compared with theoretical predictions for D* production via photon-gluon fusion into open charm. The total observed production cross-section for D*+/- mesons with laboratory energies between 22 and 86 GeV is 1.9 nb. Significant cross-section asymmetries are observed between D*+ and D*- production for nu<40 GeV and z>0.6., Comment: 22 pages, 12 figures and 2 tables
Published: 2012
Full Text: View/download PDF

28. Exclusive rho^0 muoproduction on transversely polarised protons and deuterons

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badełek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Büchele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Dünnweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger Jr, M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmüller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthörl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Heß, C., Hinterberger, F., Horikawa, N., Höppner, Ch., d'Hose, N., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Jegou, G., Joosten, R., Kabuß, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Krämer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Liska, T., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Moinester, M. A., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Negrini, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Richter, A., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlüter, T., Schmidt, K., Schmitt, L., Schönning, K., Schopferer, S., Schott, M., Schröder, W., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Wang, L., Wilfert, M., Windmolders, R., Wiślicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlev, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: The transverse target spin azimuthal asymmetry A_UT in hard exclusive production of rho^0 mesons was measured at COMPASS by scattering 160 GeV/c muons off transversely polarised protons and deuterons. The measured asymmetry is sensitive to the nucleon helicity-flip generalised parton distributions E^q, which are related to the orbital angular momentum of quarks in the nucleon. The Q^2, x_B and p_t^2 dependence of A_UT is presented in a wide kinematic range. Results for deuterons are obtained for the first time. The measured asymmetry is small in the whole kinematic range for both protons and deuterons, which is consistent with the theoretical interpretation that contributions from GPDs E^u and E^d approximately cancel., Comment: 20 pages, 9 figures and 4 tables, updated author list
Published: 2012
Full Text: View/download PDF

29. Measurement of the Cross Section for High-p_T Hadron Production in Scattering of 160 GeV/c Muons off Nucleons

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Andrieux, V., Austregesilo, A., Badellek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Berlin, A., Bernhard, J., Bertini, R., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Boer, M., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Buechele, M., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Hoeppner, Ch., Horikawa, N., d'Hose, N., Huber, S., Ishimoto, S., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kuchinski, N., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, H., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Miyachi, Y., Morreale, A., Nagaytsev, A., Nagel, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Novakova, C., Novy, J., Nowak, W. -D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Pesek, M., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Reicherz, G., Rocco, E., Rodionov, V., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, A., Schmidt, K., Schmieden, H., Schmitt, L., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Thibaud, F., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vondra, J., Wang, L., Weisrock, T., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment
Abstract: The differential cross section for production of charged hadrons with high transverse momenta in scattering of 160\,GeV/$c$ muons off nucleons at low photon virtualities has been measured at the COMPASS experiment at CERN. The results, which cover transverse momenta from 1.1\,GeV/$c$ to 3.6\,GeV/$c$, are compared to a perturbative Quantum Chromodynamics (pQCD) calculation, in order to evaluate the applicability of pQCD to this process in the kinematic domain of the experiment. The shape of the calculated differential cross section as a function of transverse momentum is found to be in good agreement with the experimental data, but the absolute scale is underestimated by next-to-leading order (NLO) pQCD. The inclusion of all-order resummation of large logarithmic threshold corrections reduces the discrepancy from a factor of three to four to a factor of two. The dependence of the cross section on the pseudo-rapidity and on virtual photon energy fraction is investigated. Finally the dependence on the charge of the hadrons is discussed., Comment: 11 pages, 4 figures and 1 table
Published: 2012
Full Text: View/download PDF

30. Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Sivers asymmetries

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Horikawa, N., Hoeppner, Ch., d'Hose, N., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Liska, T., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Moinester, M. A., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Negrini, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Richter, A., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmitt, L., Schoenning, K., Schopferer, S., Schott, M., Schroeder, W., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Wang, L., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlev, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Sivers asymmetry of the proton has been extracted in the Bjorken x range 0.003 0.03. The asymmetry is different from zero and positive also in the low x region, where sea-quarks dominate. The kinematic dependence of the asymmetry has also been investigated and results are given for various intervals of hadron and virtual photon fractional energy. In contrast to the case of the Collins asymmetry, the results on the Sivers asymmetry suggest a strong dependence on the four-momentum transfer to the nucleon, in agreement with the most recent calculations., Comment: 11 pages, 6 figures
Published: 2012
Full Text: View/download PDF

31. Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Burtin, E., Capozza, L., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Horikawa, N., Hoeppner, Ch., d'Hose, N., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jary, V., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Liska, T., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, T., Meshcheryakov, G., Meyer, W., Michigami, T., Mikhailov, Yu. V., Moinester, M. A., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Negrini, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Richter, A., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmitt, L., Schoenning, K., Schopferer, S., Schott, M., Schroeder, W., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Steiger, L., Stolarski, M., Sulc, M., Sulej, R., Suzuki, H., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Wang, L., Wilfert, M., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlev, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Collins asymmetry of the proton was extracted in the Bjorken x range 0.003
Published: 2012
Full Text: View/download PDF

32. Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badellek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Burtin, E., Chaberny, D., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger Jr, M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gazda, R., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Horikawa, N., Hoeppner, Ch., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Massmann, F., Matsuda, T., Meyer, W., Michigami, T., Mielech, A., Mikhailov, Yu. V., Moinester, M. A., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Negrini, T., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pontecorvo, G., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Richter, A., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmitt, L., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Sulej, R., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Vossen, A., Wang, L., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlevd, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: First measurements of azimuthal asymmetries in hadron-pair production in deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron) and NH_3 (proton) targets are presented. The data were taken in the years 2002-2004 and 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c at the CERN SPS. The asymmetries provide access to the transversity distribution functions, without involving the Collins effect as in single hadron production. The sizeable asymmetries measured on the NH_ target indicate non-vanishing u-quark transversity and two-hadron interference fragmentation functions. The small asymmetries measured on the ^6LiD target can be interpreted as indication for a cancellation of u- and d-quark transversities., Comment: 13 pages, 4 figures, updated to the published version
Published: 2012
Full Text: View/download PDF

33. Leading order determination of the gluon polarisation from DIS events with high-p_T hadron pairs

Author: Adolph, C., Alekseev, M. G., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Antonov, A. A., Austregesilo, A., Badelek, B., Balestra, F., Barth, J., Baum, G., Bedfer, Y., Bernhard, J., Bertini, R., Bettinelli, M., Bicker, K., Bieling, J., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Braun, C., Bravar, A., Bressan, A., Burtin, E., Chaberny, D., Chiosso, M., Chung, S. U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Das, S., Dasgupta, S. S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Filin, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gazda, R., Gerassimov, S., Geyer, R., Giorgi, M., Gnesi, I., Gobbo, B., Goertz, S., Grabmueller, S., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Guthoerl, T., Haas, F., von Harrach, D., Hedicke, S., Heinsius, F. H., Herrmann, F., Hess, C., Hinterberger, F., Horikawa, N., Hoeppner, Ch., d'Hose, N., Huber, S., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Jasinski, P., Joosten, R., Kabuss, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Korzenev, A., Kotzinian, A. M., Kouznetsov, O., Kraemer, M., Kroumchtein, Z. V., Kunne, F., Kurek, K., Lauser, L., Goff, J. -M. Le, Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Maggiora, A., Magnon, A., Makke, N., Mallot, G. K., Mann, A., Marchand, C., Martin, A., Marzec, J., Matsuda, T., Meyer, W., Michigami, T., Mikhailov, Yu. V., Moinester, M. A., Morreale, A., Mutter, A., Nagaytsev, A., Nagel, T., Nassalski, J. P., Nerling, F., Neubert, S., Neyret, D., Nikolaenko, V. I., Nowak, W. D., Nunes, A. S., Olshevsky, A. G., Ostrick, M., Padee, A., Panknin, R., Panzieri, D., Parsamyan, B., Paul, S., Perevalova, E., Pesaro, G., Peshekhonov, D. V., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pontecorvo, G., Procureur, S. L., Pretz, J., Quaresma, M., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Richter, A., Rocco, E., Rondio, E., Rossiyskaya, N. S., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Sbrizzai, G., Schiavon, P., Schill, C., Schlueter, T., Schmidt, K., Schmitt, L., Schoenning, K., Schopferer, S., Schott, M., Shevchenko, O. Yu., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Stolarski, M., Sulc, M., Sulej, R., Sznajder, P., Takekawa, S., Ter Wolbeek, J., Tessaro, S., Tessarotto, F., Tkatchev, L. G., Uhl, S., Uman, I., Vandenbroucke, M., Virius, M., Vlassov, N. V., Wang, L., Windmolders, R., Wislicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Ziembicki, M., Zhuravlev, N., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: We present a determination of the gluon polarisation Delta g/g in the nucleon, based on the longitudinal double-spin asymmetry of DIS events with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV/c polarised muon beam scattering off a polarised ^6LiD target. The gluon polarisation is evaluated by a Neural Network approach for three intervals of the gluon momentum fraction x_g covering the range 0.04 < x_g < 0.27. The values obtained at leading order in QCD do not show any significant dependence on x_g. Their average is Delta g/g = 0.125 +/- 0.060 (stat.) +/- 0.063 (syst.) at x_g=0.09 and a scale of mu^2 = 3 (GeV/c)^2., Comment: 13 pages, 6 figures and 3 tables
Published: 2012
Full Text: View/download PDF

34. Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS

Author: The COMPASS Collaboration, Alekseev, M., Alexakhin, V. Yu., Alexandrov, Yu., Alexeev, G. D., Amoroso, A., Arbuzov, A., Badełek, B., Balestra, F., Ball, J., Barth, J., Baum, G., Bedfer, Y., Bernet, C., Bertini, R., Bettinelli, M., Birsa, R., Bisplinghoff, J., Bordalo, P., Bradamante, F., Bravar, A., Bressan, A., Brona, G., Burtin, E., Bussa, M. P., Chapiro, A., Chiosso, M., Cicuttin, A., Colantoni, M., Costa, S., Crespo, M. L., Torre, S. Dalla, Dafni, T., Das, S., Dasgupta, S. S., De Masi, R., Dedek, N., Denisov, O. Yu., Dhara, L., Diaz, V., Dinkelbach, A. M., Donskov, S. V., Dorofeev, V. A., Doshita, N., Duic, V., Dünnweber, W., Eversheim, P. D., Efremov, A. V., Eyrich, W., Faessler, M., Falaleev, V., Ferrero, A., Ferrero, L., Finger, M., Finger Jr., M., Fischer, H., Franco, C., Franz, J., Friedrich, J. M., Frolov, V., Garfagnini, R., Gautheron, F., Gavrichtchouk, O. P., Gazda, R., Gerassimov, S., Geyer, R., Giorgi, M., Gobbo, B., Goertz, S., Gorin, A. M., Grabmüller, S., Grajek, O. A., Grasso, A., Grube, B., Gushterski, R., Guskov, A., Haas, F., Hannappel, J., von Harrach, D., Hasegawa, T., Heckmann, J., Hedicke, S., Heinsius, F. H., Hermann, R., Heß, C., Hinterberger, F., von Hodenberg, M., Horikawa, N., Horikawa, S., d'Hose, N., Ilgner, C., Ioukaev, A. I., Ishimoto, S., Ivanov, O., Ivanshin, Yu., Iwata, T., Jahn, R., Janata, A., Jasinski, P., Joosten, R., Jouravlev, N. I., Kabuß, E., Kang, D., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koblitz, S., Koivuniemi, J. H., Kolosov, V. N., Komissarov, E. V., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V. F., Korentchenko, A. S., Korzenev, A., Kotzinian, A. M., Koutchinski, N. A., Kouznetsov, O., Kral, A., Kravchuk, N. P., Kroumchtein, Z. V., Kuhn, R., Kunne, F., Kurek, K., Ladygin, M. E., Lamanna, M., Goff, J. M. Le, Lednev, A. A., Lehmann, A., Levorato, S., Lichtenstadt, J., Liska, T., Ludwig, I., Maggiora, A., Maggiora, M., Magnon, A., Mallot, G. K., Mann, A., Marchand, C., Marroncle, J., Martin, A., Marzec, J., Massmann, F., Matsuda, T., Maximov, A. N., Meyer, W., Mielech, A., Mikhailov, Yu. V., Moinester, M. A., Mutter, A., Nagaytsev, A., Nagel, T., Nähle, O., Nassalski, J., Neliba, S., Nerling, F., Neubert, S., Neyret, D. P., Nikolaenko, V. I., Nikolaev, K., Olshevsky, A. G., Ostrick, M., Padee, A., Pagano, P., Panebianco, S., Panknin, R., Panzieri, D., Paul, S., Pawlukiewicz-Kaminska, B., Peshekhonov, D. V., Peshekhonov, V. D., Piragino, G., Platchkov, S., Pochodzalla, J., Polak, J., Polyakov, V. A., Pretz, J., Procureur, S., Quintans, C., Rajotte, J. -F., Ramos, S., Rapatsky, V., Reicherz, G., Reggiani, D., Richter, A., Robinet, F., Rocco, E., Rondio, E., Rozhdestvensky, A. M., Ryabchikov, D. I., Samoylenko, V. D., Sandacz, A., Santos, H., Sapozhnikov, M. G., Sarkar, S., Savin, I. A., Schiavon, P., Schill, C., Schmitt, L., Schönmeier, P., Schröder, W., Shevchenko, O. Yu., Siebert, H. -W., Silva, L., Sinha, L., Sissakian, A. N., Slunecka, M., Smirnov, G. I., Sosio, S., Sozzi, F., Srnka, A., Stinzing, F., Stolarski, M., Sugonyaev, V. P., Sulc, M., Sulej, R., Tchalishev, V. V., Tessaro, S., Tessarotto, F., Teufel, A., Tkatchev, L. G., Venugopal, G., Virius, M., Vlassov, N. V., Vossen, A., Webb, R., Weise, E., Weitzel, Q., Windmolders, R., Wirth, S., Wiślicki, W., Wollny, H., Zaremba, K., Zavertyaev, M., Zemlyanichkina, E., Zhao, J., Ziegler, R., and Zvyagin, A.
Subjects: High Energy Physics - Experiment
Abstract: The measurements of the Collins and Sivers asymmetries of identified hadrons produced in deep-inelastic scattering of 160 GeV/c muons on a transversely polarised 6LiD target at COMPASS are presented. The results for charged pions and charged and neutral kaons correspond to all data available, which were collected from 2002 to 2004. For all final state particles both the Collins and Sivers asymmetries turn out to be small, compatible with zero within the statistical errors, in line with the previously published results for not identified charged hadrons, and with the expected cancellation between the u- and d-quark contributions., Comment: 16 pages, 9 figures, added author Efremov, calculated pure kaon asymmetries instead of those for experimental kaon/pion mixture (mainly error affected)
Published: 2008
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources

Refine your results

34 results on '"Grabmüller S"'

1. First measurement of the Sivers asymmetry for gluons from SIDIS data

2. Final COMPASS results on the deuteron spin-dependent structure function $g_1^{\rm d}$ and the Bjorken sum rule

3. Sivers asymmetry extracted in SIDIS at the hard scale of the Drell-Yan process at COMPASS

4. Azimuthal asymmetries of charged hadrons produced in high-energy muon scattering off longitudinally polarised deuterons

5. Multiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target

6. Exclusive $\omega$ meson muoproduction on transversely polarised protons

7. Multiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target

8. Leading-order determination of the gluon polarisation from semi-inclusive deep inelastic scattering data

9. Longitudinal double spin asymmetries in single hadron quasi-real photoproduction at high $p_T$

10. Resonance Production and $\pi\pi$ S-wave in $\pi^- + p \rightarrow \pi^- \pi^- \pi^+ + p_{recoil}$ at 190 GeV/c

11. Interplay among transversity induced asymmetries in hadron leptoproduction

12. The Spin Structure Function $g_1^{\rm p}$ of the Proton and a Test of the Bjorken Sum Rule

13. Observation of a new narrow axial-vector meson $a_1(1420)$

14. The COMPASS Setup for Physics with Hadron Beams

15. Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised proton

16. Odd and Even Partial Waves of $\eta\pi^-$ and $\eta'\pi^-$ in $\pi^-p\to\eta^{(\prime)}\pi^-p$ at $191\,\textrm{GeV}/c$

17. Search for exclusive photoproduction of Z$_c^{\pm}$(3900) at COMPASS

18. Spin alignment and violation of the OZI rule in exclusive $\omega$ and $\phi$ production in pp collisions

19. Measurement of the charged-pion polarisability

20. Measurement of radiative widths of $a_2(1320)$ and $\pi_2(1670)$

21. A high-statistics measurement of transverse spin effects in dihadron production from muon-proton semi-inclusive deep-inelastic scattering

22. Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons

23. Transverse target spin asymmetries in exclusive $\rho^0$ muoproduction

24. Hadron Transverse Momentum Distributions in Muon Deep Inelastic Scattering at 160 GeV/$c$

25. Study of \Sigma(1385) and \Xi(1321) hyperon and antihyperon production in deep inelastic muon scattering

26. Leading and Next-to-Leading Order Gluon Polarisation in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction

27. D* and D Meson Production in Muon Nucleon Interactions at 160 GeV/c

28. Exclusive rho^0 muoproduction on transversely polarised protons and deuterons

29. Measurement of the Cross Section for High-p_T Hadron Production in Scattering of 160 GeV/c Muons off Nucleons

30. Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Sivers asymmetries

31. Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries

32. Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering

33. Leading order determination of the gluon polarisation from DIS events with high-p_T hadron pairs

34. Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS

Catalog

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Publication Type

Database

34 results on '"Grabmüller S"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources