Cross section of the process $e^+e^-\to n\bar{n}$ near the threshold

Autor: Achasov, M. N., Barnyakov, A. Yu., Bedarev, E. V., Beloborodov, K. I., Berdyugin, A. V., Bogdanchikov, A. G., Botov, A. A., Dimova, T. V., Druzhinin, V. P., Zhabin, V. N., Zharinov, Yu. M., Kardapoltsev, L. V., Kasaev, A. S., Kattsin, A. A., Kovrizhin, D. P., Korol, A. A., Kupich, A. S., Kryukov, A. P., Lysenko, A. P., Melnikova, N. A., Muchnoi, N. Yu., Obrazovsky, A. E., Pakhtusova, E. V., Pugachev, K. V., Rastigeev, S. A., Rogovsky, Yu. A., Senchenko, A. I., Serednyakov, S. I., Silagadze, Z. K., Surin, I. K., Usov, Yu. V., Kharlamov, A. G., Chistyakov, D. E., Shatunov, Yu. M., Sherstyuk, S. P., Shtol, D. A.

The $e^+e^-\to n\bar{n}$ cross section was measured at center of mass (c.m.) energies from the threshold to 1908 MeV. The experiment to measure the cross section has been carried out at the VEPP-2000 $e^+e^-$ collider in 13 energy points. The SND det

Externí odkaz: http://arxiv.org/abs/2407.15308

First measurement using elliptically polarized photons of the double-polarization observable $E$ for $\gamma p \to p \pi^0$ and $\gamma p \to n \pi^+$

Autor: A2 Collaboration, Afzal, F., Spieker, K., Hurck, P., Abt, S., Achenbach, P., Adlarson, P., Ahmed, Z., Akondi, C. S., Annand, J. R. M., Arends, H. J., Bashkanov, M., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Briscoe, W. J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Fegan, S., Gardner, S., Ghosal, D., Glazier, D. I., Gorodnov, I., Gradl, W., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Kashevarov, V. L., Kay, S. J. D., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R. G., Manley, D. M., Martel, P. P., Miskimen, R., Mocanu, M., Mornacchi, E., Mullen, C., Neganov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P. B., Paudyal, D., Pedroni, P., Powell, A., Reicherz, G., Rostomyan, T., Sfienti, C., Sokhoyan, V., Steffen, O., Strakovsky, I. I., Strub, T., Supek, I., Thiel, A., Thiel, M., Thomas, A., Usov, Yu. A., Wagner, S., Walford, N. K., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., Zachariou, N.

We report the measurement of the helicity asymmetry $E$ for the $p\pi^0$ and $n\pi^+$ final states using, for the first time, an elliptically polarized photon beam in combination with a longitudinally polarized target at the Crystal Ball experiment a

Externí odkaz: http://arxiv.org/abs/2402.05531

Measurement of the neutron timelike electromagnetic form factor with the SND detector

Autor: SND Collaboration, Achasov, M. N., Barnyakov, A. Yu., Bedarev, E. V., Beloborodov, K. I., Berdyugin, A. V., Berkaev, D. E., Bogdanchikov, A. G., Botov, A. A., Dimova, T. V., Druzhinin, V. P., Zhabin, V. N., Zharinov, Yu. M., Kardapoltsev, E. V., Kasaev, A. S., Kovrizhin, D. P., Koop, I. A., Korol, A. A., Kupich, A. S., Kryukov, A. P., Lysenko, A. P., Melnikova, N. A., Muchnoy, N. Yu., Obrazovsky, A. E., Pakhtusova, E. V., Pugachev, K. V., Rastigeev, S. A., Rogovsky, Yu. A., Serednyakov, S. I., Silagadze, Z. K., Surin, I. K., Usov, Yu. V., Kharlamov, A. G., Shatunov, Yu. M., Shtol, D. A.

The results of the measurement of the $e^+e^- \to n \bar{n}$ cross section and effective neutron timelike form factor are presented. The data taking was carried out in 2020-2021 at the VEPP-2000 $e^+e^-$ collider in the center-of-mass energy range fr

Externí odkaz: http://arxiv.org/abs/2309.05241

Helicity dependent cross sections for the photoproduction of $\pi^0\pi^{\pm}$ pairs from quasi-free nucleons

Autor: A2 Collaboration, Ghosal, D., Sokhoyan, V., Fix, A., Lutterer, S., Abt, S., Achenbach, P., Afzal, F., Ahmed, Z., Annand, J. R. M., Bashkanov, M., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Briscoe, W. J., Cividini, F., Collicot, C., Costanza, S., Denig, A., Dieterle, M., Dolzhikov, A. S., Downie, E. J., Drexler, P., Fegan, S., Gardner, S., Glazier, D. I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Jermann, N., Käser, A., Kashevarov, V. L., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., MacGregor, I. J. D., Manley, D. M., Martel, P. P., Meier, Ch., Miskimen, R., Mocanu, M., Mornacchi, E., Mullen, C., Neganov, A., Neiser, A., Ostrick, M., Otte, P., Paudyal, D., Pedroni, P., Powell, A., Reicherz, G., Rostomyan, T., Spieker, K., Steffen, O., Strakovsky, I. I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Wagner, S., Walford, N. K., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., Zachariou, N.

Publikováno v: Physics Letters B, Volume 847, 10 December 2023, 138273

Photoproduction of $\pi^0\pi^{\pm}$-pairs from quasifree nucleons bound in the deuteron has been investigated to study the helicity dependence of this reaction. Measurements with a liquid deuterium target were used to extract the unpolarized cross se

Externí odkaz: http://arxiv.org/abs/2308.15240

Measurement of the branching fraction of $J/\psi\rightarrow\rho\pi$ at KEDR

Autor: Anashin, V. V., Anchugov, O. V., Andrianov, A. V., Astrelina, K. V., Aulchenko, V. M., Baldin, E. M., Baranov, G. N., Barladyan, A. K., Barnyakov, A. Yu., Barnyakov, M. Yu., Basok, I. Yu., Batrakov, A. M., Bekhtenev, E. A., Belikov, O. V., Berkaev, D. E., Blinov, A. E., Blinov, V. E., Blinov, M. F., Bobrov, A. V., Bobrovnikov, V. S., Bogomyagkov, A. V., Bolkhovityanov, D. Yu., Bondar, A. E., Buzykaev, A. R., Cheblakov, P. B., Dorohov, V. L., Emanov, F. A., Gambaryan, V. V., Grigoriev, D. N., Kaminskiy, V. V., Karnaev, S. E., Karpov, G. V., Karpov, S. V., Karukina, K. Yu., Kashtankin, D. P., Kasyanenko, P. V., Katcin, A. A., Kharlamova, T. A., Kiselev, V. A., Kononov, S. A., Krasnov, A. A., Kravchenko, E. A., Kudryavtsev, V. N., Kulikov, V. F., Kuyanov, I. A., Levichev, E. B., Logachev, P. V., Maksimov, D. A., Maltseva, Yu. I., Malyshev, V. M., Maslennikov, A. L., Meshkov, O. I., Mishnev, S. I., Morozov, I. A., Morozov, I. I., Nikiforov, D. A., Nikitin, S. A., Nikolaev, I. B., Okunev, I. N., Oreshkin, S. B., Osipov, A. A., Ovtin, I. V., Pavlenko, A. V., Peleganchuk, S. V., Piminov, P. A., Podgornov, N. A., Prisekin, V. G., Rezanova, O. L., Ruban, A. A., Savinov, G. A., Shamov, A. G., Shekhtman, L. I., Shvedov, D. A., Shwartz, B. A., Simonov, E. A., Sinyatkin, S. V., Skrinsky, A. N., Sokolov, A. V., Starostina, E. V., Sukhanov, D. P., Sukharev, A. M., Talyshev, A. A., Tayursky, V. A., Telnov, V. I., Tikhonov, Yu. A., Todyshev, K. Yu., Tribendis, A. G., Tumaikin, G. M., Usov, Yu. V., Vorobiov, A. I., Zhilich, V. N., Zhukov, A. A., Zhulanov, V. V., Zhuravlev, A. N.

We present the study of the decay $J/\psi \rightarrow \rho\pi$. The results are based on of 5.2~million $J/\psi$ events collected by the KEDR detector at the VEPP-4M collider. The branching fractions are measured to be $\B(J/\psi \rightarrow \rho\pi)

Externí odkaz: http://arxiv.org/abs/2211.13520