Observation of Beam Spin Asymmetries in the Process $e p \rightarrow e \pi^{+}\pi^{-}X$ with CLAS12
Abstract
The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function , which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function . A clear sign change is observed around the mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark.
Keywords
Cite
@article{arxiv.2101.04842,
title = {Observation of Beam Spin Asymmetries in the Process $e p \rightarrow e \pi^{+}\pi^{-}X$ with CLAS12},
author = {T. B. Hayward and C. Dilks and A. Vossen and H. Avakian and S. Adhikari and G. Angelini and M. Arratia and H. Atac and C. Ayerbe Gayoso and N. A. Baltzell and L. Barion and M. Battaglieri and I. Bedlinskiy and F. Benmokhtar and A. Bianconi and A. S. Biselli and M. Bondì and F. Bossù and S. Boiarinov and W. J. Briscoe and W. K. Brooks and D. Bulumulla and V. D. Burkert and D. S. Carman and J. C. Carvajal and A. Celentano and P. Chatagnon and T. Chetry and G. Ciullo and B. A. Clary and P. L. Cole and M. Contalbrigo and G. Costantini and V. Crede and A. D'Angelo and N. Dashyan and R. De Vita and M. Defurne and A. Deur and S. Diehl and C. Djalali and R. Dupre and M. Dugger and H. Egiyan and M. Ehrhart and A. El Alaoui and L. El Fassi and L. Elouadrhiri and S. Fegan and A. Filippi and T. A. Forest and G. Gavalian and G. P. Gilfoyle and F. X. Girod and D. I. Glazier and A. A. Golubenko and R. W. Gothe and Y. Gotra and K. A. Griffioen and M. Guidal and K. Hafidi and H. Hakobyan and M. Hattawy and F. Hauenstein and K. Hicks and A. Hobart and M. Holtrop and D. G. Ireland and E. L. Isupov and H. S. Jo and K. Joo and S. Joosten and D. Keller and M. Khachatryan and A. Khanal and A. Kim and W. Kim and A. Kripko and V. Kubarovsky and S. E. Kuhn and L. Lanza and M. Leali and S. Lee and P. Lenisa and K. Livingston and I. J. D. MacGregor and D. Marchand and N. Markov and L. Marsicano and V. Mascagna and B. McKinnon and Z. E. Meziani and M. Mirazita and V. Mokeev and A Movsisyan and C. Munoz Camacho and P. Nadel-Turonski and P. Naidoo and S. Nanda and K. Neupane and S. Niccolai and G. Niculescu and T. R. O'Connell and M. Osipenko and M. Paolone and L. L. Pappalardo and R. Paremuzyan and E. Pasyuk and W. Phelps and O. Pogorelko and Y. Prok and B. A. Raue and M. Ripani and J. Ritman and A. Rizzo and P. Rossi and J. Rowley and F. Sabatié and C. Salgado and A. Schmidt and E. P. Segarra and Y. G. Sharabian and U. Shrestha and D. Sokhan and O. Soto and N. Sparveris and S. Stepanyan and I. I. Strakovsky and S. Strauch and A. Thornton and N. Tyler and R. Tyson and M. Ungaro and L. Venturelli and H. Voskanyan and E. Voutier and D. P. Watts and K. Wei and X. Wei and M. H. Wood and B. Yale and N. Zachariou and J. Zhang},
journal= {arXiv preprint arXiv:2101.04842},
year = {2021}
}
Comments
6 pages, 5 figures