{"@context":"http://schema.org","@id":"https://doi.org/10.17182/hepdata.156806.v1","@reverse":{"isBasedOn":[{"@type":"ScholarlyArticle","identifier":{"@type":"PropertyValue","propertyID":"URL","value":"https://inspirehep.net/literature/2865315"}},{"@id":"https://doi.org/10.1103/jfzb-rfl4","@type":"JournalArticle"}]},"@type":"Dataset","additionalType":"Collection","author":{"@type":"Organization","name":"GlueX Collaboration"},"creator":{"@type":"Organization","name":"GlueX Collaboration"},"datePublished":"2025","description":"We measure for the first time the differential photoproduction cross section $d\\sigma/dt$ of the $a_2(1320)$ meson at an average photon beam energy of 8.5~GeV, using data with an integrated luminosity of 104~pb$^{-1}$ collected by the GlueX experiment. We fully reconstruct the $\\gamma p \\to \\eta\\pi^0 p$ reaction and perform a partial-wave analysis in the $a_2(1320)$ mass region with amplitudes that incorporate the linear polarization of the beam. This allows us to separate for the first time the contributions of natural- and unnatural-parity exchanges. These measurements provide novel information about the photoproduction mechanism, which is critical for the search for spin-exotic states.","hasPart":[{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t1","@type":"Dataset","description":"$a_2(1320)$ parity asymmetry, $P_{\\sigma}$, in bins of four-momentum transfer. The first uncertainty is statistical, the second systematic.","name":"Parity Asymmetry"},{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t2","@type":"Dataset","description":"$a_2(1320)$ differential cross section split into different reflectivity components, $\\frac{d\\sigma^+}{dt}$ and $\\frac{d\\sigma^-}{dt}$, in bins of four-momentum transfer. The first uncertainty...","name":"Differential Cross Section"},{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t3","@type":"Dataset","description":"$a_2(1320)$ differential cross section in the m=-1 projection split into different reflectivity components, $\\frac{d\\sigma^+_{-1}}{dt}$ and $\\frac{d\\sigma^-_{-1}}{dt}$, in bins of four-momentum...","name":"Differential Cross Section for m=-1"},{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t4","@type":"Dataset","description":"$a_2(1320)$ differential cross section in the m=-2 projection split into different reflectivity components, $\\frac{d\\sigma^+_{-2}}{dt}$ and $\\frac{d\\sigma^-_{-2}}{dt}$, in bins of four-momentum...","name":"Differential Cross Section for m=-2"},{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t5","@type":"Dataset","description":"$a_2(1320)$ differential cross section in the m=0 projection split into different reflectivity components, $\\frac{d\\sigma^+_{0}}{dt}$ and $\\frac{d\\sigma^-_{0}}{dt}$, in bins of four-momentum...","name":"Differential Cross Section for m=0"},{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t6","@type":"Dataset","description":"$a_2(1320)$ differential cross section in the m=+1 projection split into different reflectivity components, $\\frac{d\\sigma^+_{+1}}{dt}$ and $\\frac{d\\sigma^-_{+1}}{dt}$, in bins of four-momentum...","name":"Differential Cross Section for m=+1"},{"@id":"https://doi.org/10.17182/hepdata.156806.v1/t7","@type":"Dataset","description":"$a_2(1320)$ differential cross section in the m=+2 projection split into different reflectivity components, $\\frac{d\\sigma^+_{+2}}{dt}$ and $\\frac{d\\sigma^-_{+2}}{dt}$, in bins of four-momentum...","name":"Differential Cross Section for m=+2"}],"identifier":[{"@type":"PropertyValue","propertyID":"HEPDataRecord","value":"https://www.hepdata.net/record/ins2865315?version=1"},{"@type":"PropertyValue","propertyID":"HEPDataRecordAlt","value":"https://www.hepdata.net/record/156806"}],"inLanguage":"en","name":"First Measurement of $a^0_2(1320)$ Polarized Photoproduction Cross Section","provider":{"@type":"Organization","name":"HEPData"},"publisher":{"@type":"Organization","name":"HEPData"},"url":"https://www.hepdata.net/record/ins2865315?version=1","version":1}
