Physical Sciences and Mathematics Commons^™

Photoproduction Of Pi(+)Pi(-) Meson Pairs On The Proton, M Battaglieri, R De Vita, Ap Szczepaniak, Kp Adhikari, Mj Amaryan, M Anghinolfi, H Baghdasaryan, I Bedlinskiy, M Bellis, L Bibrzycki, As Biselli, C Bookwalter, D Branford, Wj Briscoe, Vd Burkert, Sl Careccia, Ds Carman, E Clinton, Pl Cole, P Collins, V Crede, D Dale, A D'Angelo, A Daniel, N Dashyan, E De Sanctis, A Deur, S Dhamija, C Djalali, Ge Dodge, D Doughty, V Drozdov, H Egiyan, P Eugenio, G Fedotov, S Fegan, A Fradi, My Gabrielyan, L Gan, M Garcon, A Gasparian, Gp Gilfoyle, Kl Giovanetti, Fx Girod, O Glamazdin, J Goett, Jt Goetz, W Gohn, E Golovatch, Rw Gothe, Ka Griffioen, M Guidal, L Guo, K Hafidi, H Hakobyan, C Hanretty, N Hassall, K Hicks, M Holtrop, Ce Hyde, Y Ilieva, Dg Ireland, El Isupov, Jr Johnstone, K Joo, D Keller, M Khandaker, P Khetarpal, W Kim, A Klein, Fj Klein, M Kossov, A Kubarovsky, V Kubarovsky, Sv Kuleshov, V Kuznetsov, Jm Laget, L Lesniak, K Livingston, Hy Lu, M Mayer, Me Mccracken, B Mckinnon, Ca Meyer, K Mikhailov, T Mineeva, M Mirazita, V Mochalov, V Mokeev, K Moriya, E Munevar, P Nadel-Turonski, I Nakagawa, Cs Nepali, S Niccolai, I Niculescu, Mr Niroula, M Osipenko, Ai Ostrovidov, K Park, S Park, M Paris, E Pasyuk, Sa Pereira, S Pisano, N Pivnyuk, O Pogorelko, S Pozdniakov, Jw Price, Y Prok, D Protopopescu, Ba Raue, G Ricco, M Ripani, Bg Ritchie, G Rosner, P Rossi, F Sabatie, Ms Saini, C Salgado, D Schott, Ra Schumacher, H Seraydaryan, Yg Sharabian, Di Sober, D Sokhan, A Stavinsky, S Stepanyan, Ss Stepanyan, P Stoler, Ii Strakovsky, S Strauch, M Taiuti, Dj Tedeschi, A Teymurazyan, S Tkachenko, M Ungaro, Mf Vineyard, Av Vlassov, Dp Watts, Lb Weinstein, Dp Weygand, M Williams, E Wolin, Mh Wood, L Zana, J Zhang, B Zhao, Zw Zhao

Michael Williams

The cross section for photoproduction of pion pairs from hydrogen has been calculated from the cut-off static theory, assuming the energy is sufficiently low that one of the mesons is produced in an S state, the other in a P state. It is shown that the cross section for this process can be expressed exactly in terms of the P-wave scattering phase shifts, provided the S-wave meson-nucleon interactions and the meson-meson interaction can be neglected. The theoretical predictions obtained here are in general agreement with preliminary experimental results.

Precise Measurement Of The Neutron Magnetic Form Factor G(M)(N) In The Few-Gev2 Region, J Lachniet, A Afanasev, H Arenhovel, Wk Brooks, Gp Gilfoyle, D Higinbotham, S Jeschonnek, B Quinn, Mf Vineyard, G Adams, Kp Adhikari, Mj Amaryan, M Anghinolfi, B Asavapibhop, G Asryan, H Avakian, H Bagdasaryan, N Baillie, Jp Ball, Na Baltzell, S Barrow, V Batourine, M Battaglieri, K Beard, I Bedlinskiy, M Bektasoglu, M Bellis, N Benmouna, Bl Berman, As Biselli, Be Bonner, C Bookwalter, S Bouchigny, S Boiarinov, R Bradford, D Branford, Wj Briscoe, S Bultmann, Vd Burkert, Jr Calarco, Sl Careccia, Ds Carman, L Casey, L Cheng, Pl Cole, A Coleman, P Collins, D Cords, P Corvisiero, D Crabb, V Crede, Jp Cummings, D Dale, A Daniel, N Dashyan, R De Masi, R De Vita, E De Sanctis, Pv Degtyarenko, H Denizli, L Dennis, A Deur, S Dhamija, Kv Dharmawardane, Ks Dhuga, R Dickson, C Djalali, Ge Dodge, D Doughty, P Dragovitsch, M Dugger, S Dytman, Op Dzyubak, H Egiyan, Ks Egiyan, L El Fassi, L Elouadrhiri, A Empl, P Eugenio, R Fatemi, G Fedotov, R Fersch, Rj Feuerbach, Ta Forest, A Fradi, My Gabrielyan, M Garcon, G Gavalian, N Gevorgyan, Kl Giovanetti, Fx Girod, Jt Goetz, W Gohn, E Golovatch, Rw Gothe, L Graham, Ka Griffioen, M Guidal, M Guillo, N Guler, L Guo, V Gyurjyan, C Hadjidakis, K Hafidi, H Hakobyan, C Hanretty, J Hardie, N Hassall, D Heddle, Fw Hersman, K Hicks, I Hleiqawi, M Holtrop, J Hu, M Huertas, Ce Hyde-Wright, Y Ilieva, Dg Ireland, Bs Ishkhanov, El Isupov, Mm Ito, D Jenkins, Hs Jo, Jr Johnstone, K Joo, Hg Juengst, T Kageya, N Kalantarians, D Keller, Jd Kellie, M Khandaker, P Khetarpal, Ky Kim, K Kim, W Kim, A Klein, Fj Klein, M Klusman, P Konczykowski, M Kossov, Lh Kramer, V Kubarovsky, J Kuhn, Se Kuhn, Sv Kuleshov, V Kuznetsov, Jm Laget, J Langheinrich, D Lawrence, Acs Lima, K Livingston, M Lowry, Hy Lu, K Lukashin, M Maccormick, S Malace, Jj Manak, N Markov, P Mattione, S Mcaleer, Me Mccracken, B Mckinnon, Jwc Mcnabb, Ba Mecking, Md Mestayer, Ca Meyer, T Mibe, K Mikhailov, T Mineeva, R Minehart, M Mirazita, R Miskimen, V Mokeev, B Moreno, K Moriya, Sa Morrow, M Moteabbed, J Mueller, E Munevar, Gs Mutchler, P Nadel-Turonski, R Nasseripour, S Niccolai, G Niculescu, I Niculescu, Bb Niczyporuk, Mr Niroula, Ra Niyazov, M Nozar, Gv O'Rielly, M Osipenko, Ai Ostrovidov, K Park, S Park, E Pasyuk, C Paterson, Sa Pereira, Sa Philips, J Pierce, N Pivnyuk, D Pocanic, O Pogorelko, E Polli, I Popa, S Pozdniakov, Bm Preedom, Jw Price, Y Prok, D Protopopescu, Lm Qin, Ba Raue, G Riccardi, G Ricco, M Ripani, Bg Ritchie, G Rosner, P Rossi, D Rowntree, Pd Rubin, F Sabatie, Ms Saini, J Salamanca, C Salgado, A Sandorfi, Jp Santoro, V Sapunenko, D Schott, Ra Schumacher, Vs Serov, Yg Sharabian, D Sharov, J Shaw, Nv Shvedunov, Av Skabelin, Es Smith, Lc Smith, Di Sober, D Sokhan, A Starostin, A Stavinsky, S Stepanyan, Ss Stepanyan, Be Stokes, P Stoler, Ka Stopani, Ii Strakovsky, S Strauch, R Suleiman, M Taiuti, S Taylor, Dj Tedeschi, R Thompson, A Tkabladze, S Tkachenko, M Ungaro, Av Vlassov, Dp Watts, X Wei, Lb Weinstein, Dp Weygand, M Williams, E Wolin, Mh Wood, A Yegneswaran, J Yun, M Yurov, L Zana, J Zhang, B Zhao, Zw Zhao

Michael Williams

The neutron elastic magnetic form factor GMn has been extracted from quasielastic electron scattering data on deuterium with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic coverage of the measurement is continuous from Q2=1 GeV2 to 4.8 GeV2. High precision was achieved by employing a ratio technique in which many uncertainties cancel, and by a simultaneous in-situ calibration of the neutron detection efficiency, the largest correction to the data. Neutrons were detected using the CLAS electromagnetic calorimeters and the time-of-flight scintillators. Data were taken at two different electron beam energies, allowing up to four semi-independent measurements of …

Beam Spin Asymmetries In Deeply Virtual Compton Scattering (Dvcs) With Clas At 4.8 Gev, G Gavalian, Vd Burkert, L Elouadrhiri, M Holtrop, S Stepanyan, D Abrahamyan, G Adams, Mj Amaryan, P Ambrozewicz, M Anghinolfi, B Asavapibhop, G Asryan, H Avakian, H Bagdasaryan, N Baillie, Jp Ball, Na Baltzell, S Barrow, V Batourine, M Battaglieri, K Beard, I Bedlinskiy, M Bektasoglu, M Bellis, N Benmouna, Bl Berman, As Biselli, Be Bonner, S Bouchigny, S Boiarinov, R Bradford, D Branford, Wj Briscoe, Wk Brooks, S Bultmann, C Butuceanu, Jr Calarco, Sl Careccia, Ds Carman, B Carnahan, S Chen, Pl Cole, A Coleman, P Collins, P Coltharp, D Cords, P Corvisiero, D Crabb, H Crannell, V Crede, Jp Cummings, N Dashyan, R De Masi, R De Vita, E De Sanctis, Pv Degtyarenko, H Denizli, L Dennis, A Deur, Kv Dharmawardane, Ks Dhuga, R Dickson, C Djalali, Ge Dodge, J Donnelly, D Doughty, P Dragovitsch, M Dugger, S Dytman, Op Dzyubak, H Egiyan, Ks Egiyan, L El Fassi, A Empl, P Eugenio, R Fatemi, G Fedotov, G Feldman, Rj Feuerbach, Ta Forest, H Funsten, M Garcon, Gp Gilfoyle, Kl Giovanetti, Fx Girod, Jt Goetz, E Golovatch, A Gonenc, Rw Gothe, Ka Griffioen, M Guidal, M Guillo, N Guler, L Guo, V Gyurjyan, C Hadjidakis, K Hafidi, H Hakobyan, Rs Hakobyan, J Hardie, N Hassall, D Heddle, Fw Hersman, K Hicks, I Hleiqawi, J Hu, M Huertas, Ce Hyde, Y Ilieva, Dg Ireland, Bs Ishkhanov, El Isupov, Mm Ito, D Jenkins, Hs Jo, K Joo, Hg Juengst, N Kalantarians, Jd Kellie, M Khandaker, Ky Kim, K Kim, W Kim, A Klein, Fj Klein, M Klusman, M Kossov, Lh Kramer, V Kubarovsky, J Kuhn, Se Kuhn, Sv Kuleshov, M Kuznetsov, J Lachniet, Jm Laget, J Langheinrich, D Lawrence, Acs Lima, K Livingston, Hy Lu, K Lukashin, M Maccormick, Jj Manak, N Markov, S Mcaleer, B Mckinnon, Jwc Mcnabb, Ba Mecking, Md Mestayer, Ca Meyer, T Mibe, K Mikhailov, R Minehart, M Mirazita, R Miskimen, V Mokeev, K Moriya, Sa Morrow, M Moteabbed, J Mueller, Gs Mutchler, P Nadel-Turonski, J Napolitano, R Nasseripour, S Niccolai, G Niculescu, I Niculescu, Bb Niczyporuk, Mr Niroula, Ra Niyazov, M Nozar, Gv O'Rielly, M Osipenko, Ai Ostrovidov, K Park, E Pasyuk, C Paterson, Sa Philips, J Pierce, N Pivnyuk, D Pocanic, O Pogorelko, E Polli, I Popa, S Pozdniakov, Bm Preedom, Jw Price, Y Prok, D Protopopescu, Lm Qin, Ba Raue, G Riccardi, G Ricco, M Ripani, Bg Ritchie, F Ronchetti, G Rosner, P Rossi, D Rowntree, Pd Rubin, F Sabatie, J Salamanca, C Salgado, Jp Santoro, V Sapunenko, Ra Schumacher, Vs Serov, Yg Sharabian, J Shaw, Nv Shvedunov, Av Skabelin, Es Smith, Lc Smith, Di Sober, D Sokhan, A Stavinsky, Ss Stepanyan, Be Stokes, P Stoler, Ii Strakovsky, S Strauch, R Suleiman, M Taiuti, S Taylor, Dj Tedeschi, U Thoma, R Thompson, A Tkabladze, S Tkachenko, C Tur, M Ungaro, Mf Vineyard, Av Vlassov, Dp Watts, Lb Weinstein, Dp Weygand, M Williams, E Wolin, Mh Wood, A Yegneswaran, J Yun, M Yurov, L Zana, J Zhang, B Zhao, Zw Zhao

Michael Williams

We report measurements of the beam spin asymmetry in deeply virtual Compton scattering (DVCS) at an electron beam energy of 4.8 GeV using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The DVCS beam spin asymmetry has been measured in a wide range of kinematics, 1.0

Measurement Of Semi-Inclusive Pi(+) Electroproduction Off The Proton, M Osipenko, M Ripani, G Ricco, H Avakian, R De Vita, G Adams, Mj Amaryan, P Ambrozewicz, M Anghinolfi, G Asryan, H Bagdasaryan, N Baillie, Jp Ball, Na Baltzell, S Barrow, M Battaglieri, I Bedlinskiy, M Bektasoglu, M Bellis, N Benmouna, Bl Berman, As Biselli, L Blaszczyk, Be Bonner, S Bouchigny, S Boiarinov, R Bradford, D Branford, Wj Briscoe, Wk Brooks, S Bultmann, Vd Burkert, C Butuceanu, Jr Calarco, Sl Careccia, Ds Carman, A Cazes, F Ceccopieri, S Chen, Pl Cole, P Collins, P Coltharp, P Corvisiero, D Crabb, V Crede, Jp Cummings, N Dashyan, R De Masi, E De Sanctis, Pv Degtyarenko, H Denizli, L Dennis, A Deur, Kv Dharmawardane, Ks Dhuga, R Dickson, C Djalali, Ge Dodge, J Donnelly, D Doughty, V Drozdov, M Dugger, S Dytman, Op Dzyubak, H Egiyan, Ks Egiyan, L El Fassi, L Elouadrhiri, P Eugenio, R Fatemi, G Fedotov, G Feldman, Rj Feuerbach, H Funsten, M Garcon, G Gavalian, Gp Gilfoyle, Kl Giovanetti, Fx Girod, Jt Goetz, E Golovach, A Gonenc, Cio Gordon, Rw Gothe, Ka Griffioen, M Guidal, M Guillo, N Guler, L Guo, V Gyurjyan, C Hadjidakis, K Hafidi, H Hakobyan, Rs Hakobyan, C Hanretty, J Hardie, N Hassall, D Heddle, Fw Hersman, K Hicks, I Hleiqawi, M Holtrop, Ce Hyde-Wright, Y Ilieva, A Ilyichev, Dg Ireland, Bs Ishkhanov, El Isupov, Mm Ito, D Jenkins, Hs Jo, K Joo, Hg Juengst, N Kalantarians, Jd Kellie, M Khandaker, W Kim, A Klein, Fj Klein, Av Klimenko, M Kossov, Z Krahn, Lh Kramer, V Kubarovsky, J Kuhn, Se Kuhn, Sv Kuleshov, J Lachniet, Jm Laget, J Langheinrich, D Lawrence, J Li, K Livingston, Hy Lu, M Maccormick, N Markov, P Mattione, S Mcaleer, M Mccracken, B Mckinnon, Jwc Mcnabb, Ba Mecking, S Mehrabyan, Jj Melone, Md Mestayer, Ca Meyer, T Mibe, K Mikhailov, R Minehart, M Mirazita, R Miskimen, V Mokeev, K Moriya, Sa Morrow, M Moteabbed, J Mueller, E Munevar, Gs Mutchler, P Nadel-Turonski, J Napolitano, R Nasseripour, S Niccolai, G Niculescu, I Niculescu, Bb Niczyporuk, Mr Niroula, Ra Niyazov, M Nozar, Gv O'Rielly, Ai Ostrovidov, K Park, E Pasyuk, C Paterson, Sa Pereira, Sa Philips, J Pierce, N Pivnyuk, D Pocanic, O Pogorelko, E Polli, I Popa, S Pozdniakov, Bm Preedom, Jw Price, Y Prok, D Protopopescu, Lm Qin, Ba Raue, G Riccardi, Bg Ritchie, G Rosner, P Rossi, Pd Rubin, F Sabatie, J Salamanca, C Salgado, Jp Santoro, V Sapunenko, Ra Schumacher, Vs Serov, Yg Sharabian, Nv Shvedunov, Av Skabelin, Es Smith, Lc Smith, Di Sober, D Sokhan, A Stavinsky, Ss Stepanyan, S Stepanyan, Be Stokes, P Stoler, Ii Strakovsky, S Strauch, M Taiuti, Dj Tedeschi, U Thoma, A Tkabladze, S Tkachenko, L Todor, L Trentadue, C Tur, M Ungaro, Mf Vineyard, Av Vlassov, Dp Watts, Lb Weinstein, Dp Weygand, M Williams, E Wolin, Mh Wood, A Yegneswaran, L Zana, J Zhang, B Zhao, Zw Zhao

Michael Williams

Semi-inclusive π+ [pi superscript +] electroproduction on protons has been measured with the CLAS detector at Jefferson Lab. The measurement was performed on a liquid-hydrogen target using a 5.75 GeV electron beam. The complete five-fold differential cross sections were measured over a wide kinematic range including the complete range of azimuthal angles between hadronic and leptonic planes, ϕ [phi], enabling us to separate the ϕ-dependent [phi-dependent] terms. Our measurements of the ϕ-independent [phi-independent] term of the cross section at low Bjorken x were found to be in fairly good agreement with pQCD calculations. Indeed, the conventional current fragmentation calculation can …

Electroproduction Of P Pi(+)Pi(-) Off Protons At 0.2 < Q(2) < 0.6 Gev2 And 1.3 < W < 1.57 Gev With The Clas Detector, Gv Fedotov, Vi Mokeev, Vd Burkert, L Elouadrhiri, En Golovatch, Bs Ishkhanov, El Isupov, Nv Shvedunov, G Adams, Mj Amaryan, P Ambrozewicz, M Anghinolfi, B Asavapibhop, G Asryan, H Avakian, H Baghdasaryan, N Baillie, Jp Ball, Na Baltzell, V Batourine, M Battaglieri, I Bedlinskiy, M Bektasoglu, M Bellis, N Benmouna, As Biselli, Be Bonner, S Bouchigny, S Boiarinov, R Bradford, D Branford, Wk Brooks, S Bultmann, C Butuceanu, Jr Calarco, Sl Careccia, Ds Carman, B Carnahan, S Chen, Pl Cole, P Coltharp, P Corvisiero, D Crabb, H Crannell, V Crede, Jp Cummings, Nb Dashyan, E De Sanctis, R De Vita, Pv Degtyarenko, H Denizli, L Dennis, Kv Dharmawardane, R Dickson, C Djalali, Ge Dodge, J Donnelly, D Doughty, M Dugger, S Dytman, Op Dzyubak, H Egiyan, Ks Egiyan, P Eugenio, R Fatemi, Rj Feuerbach, Ta Forest, H Funsten, G Gavalian, Ng Gevorgyan, Gp Gilfoyle, Kl Giovanetti, Fx Girod, Jt Goetz, Rw Gothe, Ka Griffioen, M Guidal, M Guillo, N Guler, L Guo, V Gyurjyan, C Hadjidakis, J Hardie, N Hassall, Fw Hersman, K Hicks, I Hleiqawi, M Holtrop, J Hu, M Huertas, Ce Hyde, Y Ilieva, Dg Ireland, Mm Ito, D Jenkins, Hs Jo, K Joo, Hg Juengst, Jd Kellie, M Khandaker, Ky Kim, K Kim, W Kim, A Klein, Fj Klein, A Klimenko, M Klusman, Z Krahn, Lh Kramer, V Kubarovsky, J Kuhn, Se Kuhn, S Kuleshov, J Lachniet, Jm Laget, J Langheinrich, D Lawrence, T Lee, K Livingston, N Markov, M Mccracken, B Mckinnon, Jwc Mcnabb, Ba Mecking, Md Mestayer, Ca Meyer, T Mibe, K Mikhailov, T Mineeva, R Minehart, M Mirazita, R Miskimen, K Moriya, Sa Morrow, J Mueller, Gs Mutchler, P Nadel-Turonski, R Nasseripour, S Niccolai, G Niculescu, I Niculescu, Bb Niczyporuk, Ra Niyazov, Gv O'Rielly, M Osipenko, Ai Ostrovidov, K Park, E Pasyuk, C Paterson, J Pierce, N Pivnyuk, D Pocanic, O Pogorelko, S Pozdniakov, Jw Price, Y Prok, D Protopopescu, Ba Raue, G Ricco, M Ripani, Bg Ritchie, G Rosner, P Rossi, D Rowntree, Pd Rubin, F Sabatie, C Salgado, Jp Santoro, V Sapunenko, Ra Schumacher, Vs Serov, Yg Sharabian, D Sharov, J Shaw, Es Smith, Lc Smith, Di Sober, A Stavinsky, S Stepanyan, Be Stokes, P Stoler, K Stopani, S Strauch, M Taiuti, S Taylor, Dj Tedeschi, R Thompson, A Tkabladze, S Tkachenko, L Todor, C Tur, M Ungaro, Mf Vineyard, Av Vlassov, Lb Weinstein, Dp Weygand, M Williams, E Wolin, Mh Wood, A Yegneswaran, L Zana, J Zhang

Michael Williams

This paper reports on the most comprehensive data set obtained on differential and fully integrated cross sections for the process ep→e'pπ+π- [ep→e prime p pi superscript + pi superscript -]. The data were collected with the CLAS detector at Jefferson Laboratory. Measurements were carried out in the as yet unexplored kinematic region of photon virtuality 0.2

Measurement Of Direct F(0)(980) Photoproduction On The Proton, R De Vita, Ap Szczepaniak, Kp Adhikari, M Aghasyan, Mj Amaryan, P Ambrozewicz, M Anghinolfi, G Asryan, H Avakian, H Bagdasaryan, N Baillie, Jp Ball, Na Baltzell, V Batourine, I Bedlinskiy, M Bellis, N Benmouna, Bl Berman, L Bibrzycki, As Biselli, C Bookwalter, S Bouchigny, S Boiarinov, R Bradford, D Branford, Wj Briscoe, Wk Brooks, S Bltmann, Vd Burkert, Jr Calarco, Sl Careccia, Ds Carman, L Casey, S Chen, L Cheng, E Clinton, Pl Cole, P Collins, D Crabb, H Crannell, V Crede, Jp Cummings, D Dale, A Daniel, N Dashyan, R De Masi, E De Sanctis, Pv Degtyarenko, A Deur, S Dhamija, Kv Dharmawardane, R Dickson, C Djalali, Ge Dodge, J Donnelly, D Doughty, M Dugger, Op Dzyubak, H Egiyan, Ks Egiyan, L El Fassi, L Elouadrhiri, P Eugenio, G Fedotov, R Fersch, Ta Forest, A Fradi, My Gabrielyan, L Gan, M Garoon, A Gasparian, G Gavalian, N Gevorgyan, Gp Gilfoyle, Kl Giovanetti, Fx Girod, O Glamazdin, J Goett, Jt Goetz, W Gohn, E Golovatch, Cio Gordon, Rw Gothe, L Graham, Ka Griffioen, M Guidal, N Guler, L Guo, V Gyurjyan, C Hadjidakis, K Hafidi, H Hakobyan, Rs Hakobyan, C Hanretty, J Hardie, N Hassall, D Heddle, Fw Hersman, K Hicks, I Hleiqawi, M Holtrop, Ce Hyde, Y Ilieva, Dg Ireland, Bs Ishkhanov, El Isupov, Mm Ito, D Jenkins, Hs Jo, Jr Johnstone, K Joo, Hg Juengst, T Kageya, N Kalantarians, D Keller, Jd Kellie, M Khandaker, P Khetarpal, W Kim, A Klein, Fj Klein, Av Klimenko, P Konczykowski, M Kossov, Z Krahn, Lh Kramer, V Kubarovsky, J Kuhn, Se Kuhn, Sv Kuleshov, V Kuznetsov, J Lachniet, Jm Laget, J Langheinrich, D Lawrence, T Lee, L Lesniak, J Li, K Livingston, M Lowry, Hy Lu, M Maccormick, S Malace, N Markov, P Mattione, Me Mccracken, B Mckinnon, Ba Mecking, Jj Melone, Md Mestayer, Ca Meyer, T Mibe, K Mikhailov, T Mineeva, R Minehart, M Mirazita, R Miskimen, V Mochalov, V Mokeev, B Moreno, K Moriya, Sa Morrow, M Moteabbed, E Munevar, Gs Mutchler, P Nadel-Turonski, I Nakagawa, R Nasseripour, S Niccolai, G Niculescu, I Niculescu, Bb Niczyporuk, Mr Niroula, Ra Niyazov, M Nozar, M Osipenko, Ai Ostrovidov, K Park, S Park, E Pasyuk, M Paris, C Paterson, Sa Pereira, J Pierce, N Pivnyuk, D Pocanic, O Pogorelko, S Pozdniakov, Jw Price, Y Prok, D Protopopescu, Ba Raue, G Riccardi, G Ricco, M Ripani, Bg Ritchie, G Rosner, P Rossi, F Sabati, Ms Saini, J Salamanca, C Salgado, A Sandorfi, Jp Santoro, V Sapunenko, D Schott, Ra Schumacher, Vs Serov, Yg Sharabian, D Sharov, Nv Shvedunov, Es Smith, Lc Smith, Di Sober, D Sokhan, A Starostin, A Stavinsky, S Stepanyan, Ss Stepanyan, Be Stokes, P Stoler, Ka Stopani, Ii Strakovsky, S Strauch, M Taiuti, Dj Tedeschi, A Teymurazyan, A Tkabladze, S Tkachenko, L Todor, C Tur, M Ungaro, Mf Vineyard, Av Vlassov, Dp Watts, X Wei, Lb Weinstein, Dp Weygand, M Williams, E Wolin, Mh Wood, A Yegneswaran, M Yurov, L Zana, J Zhang, B Zhao, M Battaglieri

Michael Williams

We report on the results of the first measurement of exclusive f_{0}(980) meson photoproduction on protons for E_{gamma}=3.0-3.8 GeV and -t=0.4-1.0 GeV2. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the pi;{+}pi;{-} channel by performing a partial wave analysis of the reaction gammap-->ppi;{+}pi;{-}. Clear evidence of the f_{0}(980) meson was found in the interference between P and S waves at M_{pi;{+}pi;{-}} approximately 1 GeV. The S-wave differential cross section integrated in the mass range of the f_{0}(980) was found to be a factor of about …

Search For The Photoexcitation Of Exotic Mesons In The Pi(+)Pi(+)Pi(-) System, M Nozar, C Salgado, Dp Weygand, L Guo, G Adams, J Li, P Eugenio, Mj Amaryan, M Anghinolfi, G Asryan, H Avakian, H Bagdasaryan, N Baillie, Jp Ball, Na Baltzell, S Barrow, M Battaglieri, I Bedlinskiy, M Bektasoglu, M Bellis, N Benmouna, Bl Berman, As Biselli, L Blaszczyk, Be Bonner, S Bouchigny, S Boiarinov, R Bradford, D Branford, Wj Briscoe, Wk Brooks, S Bultmann, Vd Burkert, C Butuceanu, Jr Calarco, Sl Careccia, Ds Carman, B Carnahan, L Casey, A Cazes, S Chen, L Cheng, Pl Cole, P Collins, P Coltharp, D Cords, P Corvisiero, D Crabb, H Crannell, V Crede, Jp Cummings, D Dale, N Dashyan, R De Masi, R De Vita, E De Sanctis, Pv Degtyarenko, H Denizli, L Dennis, A Deur, Kv Dharmawardane, Ks Dhuga, R Dickson, C Djalali, Ge Dodge, D Doughty, M Dugger, S Dytman, Op Dzyubak, H Egiyan, Ks Egiyan, L El Fassi, L Elouadrhiri, R Fatemi, G Fedotov, Rj Feuerbach, Ta Forest, A Fradi, H Funsten, M Garcon, G Gavalian, N Gevorgyan, Gp Gilfoyle, Kl Giovanetti, Fx Girod, Jt Goetz, Rw Gothe, Ka Griffioen, M Guidal, M Guillo, N Guler, V Gyurjyan, C Hadjidakis, K Hafidi, H Hakobyan, C Hanretty, J Hardie, N Hassall, D Heddle, Fw Hersman, K Hicks, I Hleiqawi, M Holtrop, Ce Hyde-Wright, Y Ilieva, Dg Ireland, Bs Ishkhanov, El Isupov, Mm Ito, D Jenkins, Hs Jo, Jr Johnstone, K Joo, Hg Juengst, N Kalantarians, Jd Kellie, M Khandaker, W Kim, A Klein, Fj Klein, M Kossov, Z Krahn, Lh Kramer, V Kubarovsky, J Kuhn, Se Kuhn, Sv Kuleshov, V Kuznetsov, J Lachniet, Jm Laget, J Langheinrich, D Lawrence, K Livingston, Hy Lu, M Maccormick, N Markov, P Mattione, S Mcaleer, B Mckinnon, Jwc Mcnabb, Ba Mecking, S Mehrabyan, Md Mestayer, Ca Meyer, T Mibe, K Mikhailov, M Mirazita, R Miskimen, V Mokeev, B Moreno, K Moriya, Sa Morrow, M Moteabbed, J Mueller, E Munevar, Gs Mutchler, P Nadel-Turonski, R Nasseripour, S Niccolai, G Niculescu, I Niculescu, Bb Niczyporuk, Mr Niroula, Ra Niyazov, Gv O'Rielly, M Osipenko, Ai Ostrovidov, K Park, E Pasyuk, C Paterson, Sa Pereira, Sa Philips, J Pierce, N Pivnyuk, D Pocanic, O Pogorelko, E Polli, I Popa, S Pozdniakov, Bm Preedom, Jw Price, Y Prok, D Protopopescu, Lm Qin, Ba Raue, G Riccardi, G Ricco, M Ripani, Bg Ritchie, F Ronchetti, G Rosner, P Rossi, Pd Rubin, F Sabatie, J Salamanca, Jp Santoro, V Sapunenko, Ra Schumacher, Vs Serov, Yg Sharabian, D Sharov, Nv Shvedunov, Av Skabelin, Es Smith, Lc Smith, Di Sober, D Sokhan, A Stavinsky, Ss Stepanyan, S Stepanyan, Be Stokes, P Stoler, Ii Strakovsky, S Strauch, M Taiuti, Dj Tedeschi, U Thoma, A Tkabladze, S Tkachenko, L Todor, M Ungaro, Mf Vineyard, Av Vlassov, Dp Watts, Lb Weinstein, M Williams, E Wolin, Mh Wood, A Yegneswaran, L Zana, J Zhang, B Zhao, Zw Zhao

Michael Williams

A search for exotic mesons in the pi;{+}pi;{+}pi;{-} system photoproduced by the charge exchange reaction gammap-->pi;{+}pi;{+}pi;{-}(n) was carried out by the CLAS Collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A partial wave analysis was performed on a sample of 83 000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic J;{PC}=1;{-+} resonant state in the 1 …

Lake El’Gygytgyn’S Emerging Ipy Record Of Pliocene To Recent Arctic Change, Julie Brigham_Grette, Martin Melles, Pavel Minyuk, Christian Koberl

Julie Brigham-Grette

Lacustrine sediments representing the last 3 glacial cycles from NE Russia chronicle the magnitude and dynamics of millennial-scale change across the western Arctic. Logistics are now underway in a multi-national effort to collect the complete paleoclimate archive from this region back to 3.6 Myr ago.

Actinorhodopsin Genes Discovered Diverse In Freshwater Habitats And Among Cultivated Actinobacteria, A.K. Sharma, K. Sommerfeld, G.S. Bullerjahn, A.R. Matteson, Steven Wilhelm, J. Jezbera, U. Brandt, W.F. Doolittle, M.W. Hahn

Steven Wilhelm

Microbial rhodopsins are membrane proteins that utilize a retinal chromophore to harvest sunlight for energetic and photosensory functions. Recently, a group of novel rhodopsin sequences named ‘actinorhodopsins’ (ActRs) was hypothesized to exist among uncultured planktonic Actinobacteria. ActRs were discovered by mining metagenomic data obtained during the Venter Institute’s Global Ocean Sampling expedition, from a hypersaline lagoon, two estuaries and a freshwater lake. On the basis of these findings, and many studies that show Actinobacteria are common inhabitants of lakes, we predicted that ActR genes would likely be present in other freshwater habitats and among the genomes of cultivated Actinobacteria …

Identifying The Source Of Unknown Microcystin Genes And Predicting Microcystin Variants By Comparing Genes Within Uncultured Cyanobacterial Cells, C.J. Allender, G.R. Lecleir, J.M. Rinta-Kanto, R.L. Small, M.F. Satchwell, G.L. Boyer, Steven Wilhelm

Steven Wilhelm

While multiple phylogenetic markers have been used in the culture independent study of microcystin producing cyanobacteria, in only a few instances have multiple markers been studied within individual cells, and in all cases these studies have been conducted with cultured isolates. Here, we isolate and evaluate large DNA fragments (> 6 kb) encompassing two genes involved in microcystin biosynthesis (mcyA2 and mcyB1) and use them to identify the source of gene fragments found in water samples. Further investigation of these gene loci from individual cyanobacterial cells allowed for improved analysis of the genetic diversity within microcystin producers as …

Distribution Of Calcifying And Silicifying Phytoplankton In Relation To Environmental And Biogeochemical Parameters During The Late Stages Of The 2005 North East Atlantic Spring Bloom, K. Leblanc, C.E. Hare, Y. Feng, G.M. Berg, G.R. Ditullio, A. Neeley, I. Benner, C. Sprengel, A. Beck, S.A. Sanudo-Wilhemy, U. Passow, K. Klinck, J.M. Rowe, Steven Wilhelm, C.W. Brown, D.A. Hutchins

Steven Wilhelm

The late stage of the North East Atlantic (NEA) spring bloom was investigated during June 2005 along a transect section from 45 to 66° N between 15 and 20° W in order to characterize the contribution of siliceous and calcareous phytoplankton groups and describe their distribution in relation to environmental factors. We measured several biogeochemical parameters such as nutrients, surface trace metals, algal pigments, biogenic silica (BSi), particulate inorganic carbon (PIC) or calcium carbonate, particulate organic carbon, nitrogen and phosphorus (POC, PON and POP, respectively), as well as transparent exopolymer particles (TEP). Results were compared with other studies undertaken in …

The Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom: I. The Phytoplankton Community And Biogeochemical Response, Y. Feng, C.E. Hare, K. Leblanc, J.M. Rose, Y Zhang, G.R. Ditullio, P. Lee, Steven Wilhelm, J.M. Rowe, J. Sun, N. Nemcek, C. Gueguen, U. Passow, I. Benner, C. Brown, D.A. Hutchins

Steven Wilhelm

ABSTRACT: The North Atlantic spring bloom is one of the largest annual biological events in the ocean, and is characterized by dominance transitions from siliceous (diatoms) to calcareous (coccolithophores) algal groups. To study the effects of future global change on these phytoplankton and the biogeochemical cycles they mediate, a shipboard continuous culture experiment (Ecostat) was conducted in June 2005 during this transition period. Four treatments were examined: (1) 12°C and 390 ppm CO₂ (ambient control), (2) 12°C and 690 ppm CO₂ (high pCO₂), (3) 16°C and 390 ppm CO₂ (high temperature), and (4) 16°C and …

Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom: Iii. Dimethylsulfoniopropionate, P.A. Lee, J.R. Rudisill, A.R. Neeley, D.A. Hutchins, Y. Feng, C.E. Hare, K. Leblanc, J.M. Rose, Steven Wilhelm, J.M. Rowe, G.R. Ditullio

Steven Wilhelm

The CLAW hypothesis argues that a negative feedback mechanism involving phytoplankton-derived dimethylsulfoniopropionate (DMSP) could mitigate increasing sea surface temperatures that result from global warming. DMSP is converted to the climatically active dimethylsulfide (DMS), which is transferred to the atmosphere and photochemically oxidized to sulfate aerosols, leading to increases in planetary albedo and cooling of the Earth’s atmosphere. A shipboard incubation experiment was conducted to investigate the effects of increased temperature and pCO2 on the algal community structure of the North Atlantic spring bloom and their subsequent impact on particulate and dissolved DMSP concentrations (DMSP_p and DMSP_d). Under …

Performance Of A Single-Crystal Diamond-Pixel Telescope, R. Hall-Wilton, V. Ryjov, M. Pernicka, V. Halyo, B. Harrop, A. Hunt, D. Marlow, E. Bartz, J. Doroshenko, D. Hits, S. Schnetzer, R. Stone, W. Bugg, M. Hollingsworth, Stefan Spanier, W. Johns

stefan spanier

We describe the results from a beam test of a telescope consisting of three planes of single-crystal, diamond pixel detectors. This telescope is a prototype for a proposed small-angle luminosity monitor, the Pixel Luminosity Telescope (PLT), for CMS. We recorded the pixel addresses and pulse heights of all pixels over threshold as well as the fast-or signals from all three telescope planes. We present results on the telescope performance including occupancies, pulse heights, fast-or efficiencies and particle tracking. These results show that the PLT design concept is sound and indicate that the project is ready to proceed with the next …

Efficient Methods For Topic Model Inference On Streaming Document Collections, Limin Yao, David Mimno, Andrew Mccallum

Andrew McCallum

Topic models provide a powerful tool for analyzing large text collections by representing high dimensional data in a low dimensional subspace. Fitting a topic model given a set of training documents requires approximate inference techniques that are computationally expensive. With today's large-scale, constantly expanding document collections, it is useful to be able to infer topic distributions for new documents without retraining the model. In this paper, we empirically evaluate the performance of several methods for topic inference in previously unseen documents, including methods based on Gibbs sampling, variational inference, and a new method inspired by text classification. The classification-based inference …

Towards Theoretical Bounds For Resource-Bounded Information Gathering For Correlation Clustering, Pallika Kanani, Andrew Mccallum, Ramesh Sitaraman

Andrew McCallum

Resource-bounded Information Gathering for Correlation Clustering deals with designing efficient methods for obtaining and incorporating information from external sources to improve accuracy of clustering tasks. In this paper, we formulate the problem, and some specific goals and lay the foundation for better theoretical understanding of this framework. We address the challenging problem of analytically quantifying the effect of changing a single edge weight on the partitioning of the entire graph, under some simplifying assumptions, hence demonstrating a method to calculate the expected reduction in error. Our analysis of different query selection criteria provides a formal way of comparing different heuristics. …

Bi-Directional Joint Inference For Entity Resolution And Segmentation Using Imperatively-Defined Factor Graphs, Sameer Singh, Karl Schultz, Andrew Mccallum

Andrew McCallum

There has been growing interest in using joint inference across multiple subtasks as a mechanism for avoiding the cascading accumulation of errors in traditional pipelines. Several recent papers demonstrate joint inference between the segmentation of entity mentions and their de-duplication, however, they have various weaknesses: inference information flows only in one direction, the number of uncertain hypotheses is severely limited, or the subtasks are only loosely coupled. This paper presents a highly-coupled, bi-directional approach to joint inference based on efficient Markov chain Monte Carlo sampling in a relational conditional random field. The model is specified with our new probabilistic programming …

Semi-Supervised Learning Of Dependency Parsers Using Generalized Expectation Criteria, Gregory Druck, Gideon Mann, Andrew Mccallum

Andrew McCallum

In this paper, we propose a novel method for semi-supervised learning of non-projective log-linear dependency parsers using directly expressed linguistic prior knowledge (e.g.~a noun's parent is often a verb). Model parameters are estimated using a generalized expectation (GE) objective function that penalizes the mismatch between model predictions and linguistic expectation constraints. In a comparison with two prominent "unsupervised" learning methods that require indirect biasing toward the correct syntactic structure, we show that GE can attain better accuracy with as few as 20 intuitive constraints. We also present positive experimental results on longer sentences in multiple languages.

Inference And Learning In Large Factor Graphs With Adaptive Proposal Distributions And A Rank-Based Objective, Khashayar Rohanimanesh, Michael Wick, Andrew Mccallum

Andrew McCallum

Large templated factor graphs with complex structure that changes during inference have been shown to provide state-of-the-art experimental results in tasks such as identity uncertainty and information integration. However, inference and learning in these models is notoriously difficult. This paper formalizes, analyzes and proves convergence for the SampleRank algorithm, which learns extremely efficiently by calculating approximate parameter estimation gradients from each proposed MCMC jump. Next we present a parameterized, adaptive proposal distribution, which greatly increases the number of accepted jumps. We combine these methods in experiments on a real-world information extraction problem and demonstrate that the adaptive proposal distribution requires …

An Entity Based Model For Coreference Resolution, Michael Wick, Aron Culotta, Khashayar Rohanimanesh, Andrew Mccallum

Andrew McCallum

Recently, many advanced machine learning approaches have been proposed for coreference resolution; however, all of the discriminatively-trained models reason over mentions, rather than entities. That is, they do not explicitly contain variables indicating the ``canonical'' values for each attribute of an entity (e.g., name, venue, title, etc.). This canonicalization step is typically implemented as a post-processing routine to coreference resolution prior to adding the extracted entity to a database. In this paper, we propose a discriminatively-trained model that jointly performs coreference resolution and canonicalization, enabling features over hypothesized entities. We validate our approach on two different coreference problems: newswire anaphora …

Active Learning By Labeling Features, Gregory Druck, Burr Settles, Andrew Mccallum

Andrew McCallum

Methods that learn from prior information about input features such as generalized expectation (GE) have been used to train accurate models with very little effort. In this paper, we propose an active learning approach in which the machine solicits "labels" on features rather than instances. In both simulated and real user experiments on two sequence labeling tasks we show that our active learning method outperforms passive learning with features as well as traditional active learning with instances. Preliminary experiments suggest that novel interfaces which intelligently solicit labels on multiple features facilitate more efficient annotation.

Pompeiu's Theorem Revisited, Árpád Bényi

Árpád Bényi

Pompeiu's theorem states that if ABC is an equilateral triangle and M a point in its plane, then MA, MB, and MC form a new triangle. In this article, we have a new look at this theorem in the realm of arbitrary triangles. We discover what we call Pompeiu's Area Formula, a neat equality relating areas of triangles determined by the points A, B, C, and M.

Remnants Of Medieval Field Patterns In The Czech Republic: Analysis Of Driving Forces Behind Their Disappearance With Special Attention To The Role Of Hedgerows, Petr Sklenicka, Kristina Molnarova, Elizabeth Brabec, Peter Kumble, Blanka Pittnerova, Katerina Pixova, Miroslav Salek

Elizabeth Brabec

Remnants of medieval field patterns, called “pluzina” in the Czech Republic, are valuable historical landscapes, similar in character to the bocage landscapes typical for some countries in Western Europe. The original historical pattern of fields and meadows has persisted due to the stabilizing network of hedgerows. As in other countries, the development of these medieval fields in recent decades for intensive agriculture or residential purposes has led to their dramatic decline. This study evaluates the dynamics of the development of medieval pluzina hedgerows during the second half of the 20th century in the Plzen Region of the Czech Republic, using …

Umass Libraries 2009, Maxine G. Schmidt

Maxine G Schmidt

No abstract provided.

Periodic Traveling Waves In Sirs Endemic Models, Tong Li, Yi Li, Herbert W. Hethcote

Yi Li

Mathematical models are used to determine if infection wave fronts could occur by traveling geographically in a loop around a region or continent. These infection wave fronts arise by Hopf bifurcation for some spatial models for infectious disease transmission with distributed-contacts. Periodic traveling waves are shown to exist for the spatial analog of the SIRS endemic model, in which the temporary immunity is described by a delay, but they do not exist in a similar spatial SIRS endemic model without a delay. Specifically, we found that the ratio of the delay ω in the recovered class and the average infectious …

A Note On The Positive Solutions Of An Inhomogeneous Elliptic Equation On Rn, Yinbin Deng, Yi Li, Fen Yang

Yi Li

This paper is contributed to the elliptic equation (0.1) Δu+K(|x|)up+μf(|x|)=0,

where p>1, x∈Rn, n⩾3, and μ⩾0 is a constant. We study the structure of positive radial solutions of (0.1) and obtain the uniqueness of solution decaying faster than r−m at ∞ if μ is small enough under some assumptions on K and f, where m is the slow decay rate.

Factorie: Probabilistic Programming Via Imperatively Defined Factor Graphs, Andrew Mccallum, Karl Schultz, Sameer Singh

Andrew McCallum

Discriminatively trained undirected graphical models have had wide empirical success, and there has been increasing interest in toolkits that ease their application to complex relational data. The power in relational models is in their repeated structure and tied parameters; at issue is how to define these structures in a powerful and flexible way. Rather than using a declarative language, such as SQL or first-order logic, we advocate using an imperative language to express various aspects of model structure, inference, and learning. By combining the traditional, declarative, statistical semantics of factor graphs with imperative definitions of their construction and operation, we …

Generalized Expectation Criteria For Bootstrapping Extractors Using Record-Text Alignment, Kedar Bellare, Andrew Mccallum

Andrew McCallum

Traditionally, machine learning approaches for information extraction require human annotated data that can be costly and time-consuming to produce. However, in many cases, there already exists a database (DB) with schema related to the desired output, and records related to the expected input text. We present a conditional random field (CRF) that aligns tokens of a given DB record and its realization in text. The CRF model is trained using only the available DB and unlabeled text with generalized expectation criteria. An annotation of the text induced from inferred alignments is used to train an information extractor. We evaluate our …

Alternating Projections For Learning With Expectation Constraints, Kedar Bellare, Gregory Druck, Andrew Mccallum

Andrew McCallum

We present an objective function for learning with unlabeled data that utilizes auxiliary expectation constraints. We optimize this objective function using a procedure that alternates between information and moment projections. Our method provides an alternate interpretation of the posterior regularization framework (Graca et al., 2008), maintains uncertainty during optimization unlike constraint-driven learning (Chang et al., 2007), and is more efficient than generalized expectation criteria (Mann & McCallum, 2008). Applications of this framework include minimally supervised learning, semisupervised learning, and learning with constraints that are more expressive than the underlying model. In experiments, we demonstrate comparable accuracy to generalized expectation criteria …

Training Factor Graphs With Reinforcement Learning For Efficient Map Inference, Michael Wick, Khashayar Rohanimanesh, Sameer Singh, Andrew Mccallum

Andrew McCallum

Large, relational factor graphs with structure defined by first-order logic or other languages give rise to notoriously difficult inference problems. Because unrolling the structure necessary to represent distributions over all hypotheses has exponential blow-up, solutions are often derived from MCMC. However, because of limitations in the design and parameterization of the jump function, these sampling-based methods suffer from local minima--the system must transition through lower-scoring configurations before arriving at a better MAP solution. This paper presents a new method of explicitly selecting fruitful downward jumps by leveraging reinforcement learning (RL). Rather than setting parameters to maximize the likelihood of the …