English
Related papers

Related papers: Spin-Density Matrix Elements for Vector Meson Phot…

200 papers

We use gauge/gravity duality to study vector meson (J/{\Psi}, {\rho}_0, {\Omega}, {\Phi}) production in electron-proton scattering, in the limit of high center of mass energy at fixed momentum transfer, corresponding to the limit of low…

High Energy Physics - Phenomenology · Physics 2015-06-16 Miguel S. Costa , Marko Djurić , Nick Evans

The purpose of the ALICE experiment at the LHC is the study of the Quark Gluon Plasma (QGP) formed in ultra-relativistic heavy-ion collisions, a state of matter in which quarks and gluons are deconfined. The properties of this state of…

High Energy Physics - Experiment · Physics 2019-08-13 L. Massacrier

In this paper, we explore the possibility of measuring the complete polarizations of cosmic photons $\gamma$ and the polarizations of cosmic electrons $e^{-}$ and positrons $e^{+}$. Our innovative Vector Meson Photo-production induced…

High Energy Physics - Phenomenology · Physics 2023-07-04 Dart-yin A. Soh , Zhaoyi Qu

Exclusive electroproduction of rho^0 mesons has been measured using the ZEUS detector at HERA in two Q^2 ranges, 0.25<Q^2<0.85 GeV^2 and 3<Q^2<30 GeV^2. The low-Q^2 data span the range 20<W<90 GeV; the high-Q^2 data cover the 40<W<120 GeV…

High Energy Physics - Experiment · Physics 2012-08-27 ZEUS Collaboration

We report on the concept of an innovative source to produce polarized proton/deuteron beams of a kinetic energy up to several GeV from a laser-driven plasma accelerator. Spin effects have been implemented into the PIC simulation code VLPL…

The STAR Collaboration has reported a significant $\phi$-meson global spin alignment ($\rho_{00}$) signal in Au+Au collisions at $\sqrt{s_{NN}}\leq62$ GeV by measuring the polar angle distribution of $\phi$-meson daughters with respect to…

Nuclear Experiment · Physics 2025-10-23 Gavin Wilks , Xu Sun , Zhenyu Ye

Baryon - anti-baryon photoproduction off a proton target is being studied in detail at Jefferson Lab with the GlueX Experiment. We observe $p\bar{p}$ and, for the first time, $\Lambda\bar{\Lambda}$ photoproduction (with $\Lambda \rightarrow…

Nuclear Experiment · Physics 2020-08-26 Hao Li , Reinhard A. Schumacher

Hall D at Jefferson lab is an ideal place to install a polarized deuteron target which can be ''tensor polarized", allowing the separation of the spin states $m=0,\pm1$ or the measurement of tensor asymmetries. The bremsstrahlung photon…

Nuclear Experiment · Physics 2025-05-01 Mark M. Dalton , Alexandre Deur , Chris Keith

Spin observables may reveal much deeper properties of non perturbative hadronic physics than unpolarized quantities. We discuss the polarization of hadrons produced in $e^+e^-$ annihilation at LEP. We show how final state $q \bar q$…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mauro Anselmino

Exclusive production of $\phi$ mesons on hydrogen and deuterium targets is studied in the HERMES kinematic region $1 < Q^{2} < 7$ GeV$^2$ and $3.0 < W < 6.3$ GeV. Spin density matrix elements and their $Q^{2}$ and $t$ dependences are…

High Energy Physics - Experiment · Physics 2008-10-14 HERMES Collaboration , W. Augustyniak , A. Borissov , S. Manayenkov

One of the key objectives of the COMPASS experiment at CERN is the determination of the gluon contribution to the nucleon spin. The gluon polarization is measured via photon-gluon fusion in deep-inelastic scattering of 160 GeV/c polarized…

High Energy Physics - Experiment · Physics 2017-08-23 C. Schill

A frozen spin polarized target, constructed at Jefferson Lab for use inside a large acceptance spectrometer, is described. The target has been utilized for photoproduction measurements with polarized tagged photons of both longitudinal and…

Instrumentation and Detectors · Physics 2015-06-04 C. D. Keith , J. Brock , C. Carlin , S. A. Comer , D. Kashy , J. McAndrew , D. G. Meekins , E. Pasyuk , J. J Pierce , M. L. Seely

We study the coherent photoproduction of light vector mesons in Pb-Pb collisions in the framework of color dipole approach. We employ the Glauber--Gribov formalism supplemented by an effective suppression factor $R_G$ accounting for the…

High Energy Physics - Phenomenology · Physics 2026-05-15 Cheryl Henkels , Emmanuel G. de Oliveira , Roman Pasechnik , Haimon Trebien

Excited vector mesons, some of which are predicted to include gluonic excitation in their wavefunctions, and certain classes of axial vector mesons, some of which are implicated in the decay of spin-exotic mesons, decay dominantly to…

Nuclear Experiment · Physics 2023-10-23 Amy M. Schertz

In this letter we study the photoproduction of scalar mesons in the intermediate energies considering distinct mixing scenarios in the description of meson physical states. The differential and integrated total cross section are computed…

High Energy Physics - Phenomenology · Physics 2013-05-30 M. L. L. da Silva , M. V. T. Machado

The exclusive electroproduction of rho-0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements…

High Energy Physics - Experiment · Physics 2009-08-17 The HERMES Collaboration , A. Airapetian

Mathematical ambiguities in partial-wave analysis present a significant challenge to the extraction of resonance properties in hadronic reactions. Recent work has shown that while linear photon polarization can resolve continuous…

High Energy Physics - Phenomenology · Physics 2025-09-24 Derek I. Glazier , Vincent Mathieu

The photoproduction of $\pi^+\pi^-$ meson pairs off the proton has been studied in the reaction $\gamma p\to p\,\pi^+\pi^-$ using the CEBAF Large Acceptance Spectrometer (CLAS) and the frozen-spin target (FROST) in Hall B at the Thomas…

Nuclear Experiment · Physics 2025-05-01 P. Roy , S. Cao , V. Crede , E. Klempt , V. A. Nikonov , A. V. Sarantsev , V. D. Burkert , V. Mokeev , P. Achenbach , J. S. Alvarado , W. R. Armstrong , H. Atac , H. Avakian , N. A. Baltzell , L. Barion , M. Bashkanov , M. Battaglieri , F. Benmokhtar , A. Bianconi , A. S. Biselli , M. Bondi , F. Bossu , S. Boiarinov , K. -T. Brinkmann , W. J. Briscoe , W. K. Brooks , T. Cao , R. Capobianco , D. S. Carman , P. Chatagnon , G. Ciullo , P. L. Cole , M. Contalbrigo , A. D'Angelo , N. Dashyan , R. DeVita , M. Defurne , A. Deur , S. Diehl , C. Djalali , M. Dugger , R. Dupre , H. Egiyan , A. El Alaoui , L. El Fassi , P. Eugenio , S. Fegan , I. P. Fernando , A. Filippi , G. Gavalian , R. W. Gothe , L. Guo , K. Hafidi , H. Hakobyan , M. Hattawy , T. B. Hayward , D. Heddle , A. Hobart , M. Holtrop , Y. Ilieva , D. G. Ireland , E. L. Isupov , D. Jenkins , H. Jiang , H. S. Jo , K. Joo , S. Joosten , D. Keller , M. Khandaker , A. Kim , W. Kim , F. J. Klein , V. Klimenko , A. Kripko , V. Kubarovsky , L. Lanza , P. Lenisa , X. Li , K. Livingston , I. J. D. MacGregor , D. Marchand , D. Martiryan , V. Mascagna , D. Matamoros , M. E. McCracken , B. McKinnon , T. Mineeva , C. Munoz Camacho , P. Nadel-Turonski , K. Neupane , D. Nguyen , G. Niculescu , M. Osipenko , A. I. Ostrovidov , M. Ouillon , P. Pandey , M. Paolone , L. L. Pappalardo , R. Paremuzyan , E. Pasyuk , S. J. Paul , W. Phelps , N. Pilleux , S. Polcher Rafael , J. Price , Y. Prok , D. Protopopescu , J. Richards , M. Ripani , B. Ritchie , J. Ritman , G. Rosner , P. Rossi , A. A. Rusova , C. Salgado , S. Schadmand , A. Schmidt , R. A. Schumacher , Y. G. Sharabian , E. V. Shirokov , S. Shrestha , D. Sokhan , N. Sparveris , M. Spreafico , I. I. Strakovsky , S. Strauch , J. A. Tan , M. Tenorio , N. Trotta , R. Tyson , M. Ungaro , S. Vallarino , L. Venturelli , T. Vittorini , H. Voskanyan , E. Voutier , D. P. Watts , U. Weerasinghe , X. Wei , M. H. Wood , L. Xu , N. Zachariou , Z. W. Zhao , M. Zurek

Continuing our previous study of Deeply Virtual Meson Production (DVMP) at twist-3 accuracy, we derive compact expressions for all helicity amplitudes. We perform a phenomenological analysis of the helicity-amplitude ratio…

High Energy Physics - Phenomenology · Physics 2026-03-27 Renaud Boussarie , Luigi Delle Rose , Michael Fucilla , Alessandro Papa , Lech Szymanowski , Samuel Wallon