cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.17182/hepdata.132013.v1/t79
title: "E_25" of "Helicity-dependent cross sections and double-polarization observable E in eta photoproduction from quasi-free protons and neutrons"

description: Beam-target asymmetry E at W= 1.847 GeV
description: A2 Collaboration at MAMI.
Precise helicity-dependent cross sections and the
double-polarization observable E were measured for $\eta$
photoproduction from quasifree protons and neutrons bound in the
deuteron. The $2\gamma$ and $3\pi^0$ decay modes were used to optimize
the statistical quality of the data and to estimate systematic
uncertainties. The measurement used the A2 detector setup at the
tagged photon beam of the electron accelerator MAMI in Mainz.
A longitudinally polarized deuterated butanol target was used in
combination with a circularly polarized photon beam from
bremsstrahlung of a longitudinally polarized electron beam. The
reaction products were detected with the electromagnetic
calorimeters Crystal Ball and TAPS, which covered 98% of the full
solid angle. The main systematic uncertainty of the E asymmetry
is related to the measurement of the beam and target
polarizations. The uncertainty of the photon polarization degree
was determined to be ±2.7%. The uncertainty of the target
polarization was estimated as ±10%.
DOI: 10.17182/hepdata.132013.v1/t80
title: "E_26" of "Helicity-dependent cross sections and double-polarization observable E in eta photoproduction from quasi-free protons and neutrons"

description: Beam-target asymmetry E at W= 1.863 GeV
description: A2 Collaboration at MAMI.
Precise helicity-dependent cross sections and the
double-polarization observable E were measured for $\eta$
photoproduction from quasifree protons and neutrons bound in the
deuteron. The $2\gamma$ and $3\pi^0$ decay modes were used to optimize
the statistical quality of the data and to estimate systematic
uncertainties. The measurement used the A2 detector setup at the
tagged photon beam of the electron accelerator MAMI in Mainz.
A longitudinally polarized deuterated butanol target was used in
combination with a circularly polarized photon beam from
bremsstrahlung of a longitudinally polarized electron beam. The
reaction products were detected with the electromagnetic
calorimeters Crystal Ball and TAPS, which covered 98% of the full
solid angle. The main systematic uncertainty of the E asymmetry
is related to the measurement of the beam and target
polarizations. The uncertainty of the photon polarization degree
was determined to be ±2.7%. The uncertainty of the target
polarization was estimated as ±10%.
DOI: 10.17182/hepdata.132013.v1/t81
title: "E_27" of "Helicity-dependent cross sections and double-polarization observable E in eta photoproduction from quasi-free protons and neutrons"

description: Beam-target asymmetry E at W= 1.883 GeV
description: A2 Collaboration at MAMI.
Precise helicity-dependent cross sections and the
double-polarization observable E were measured for $\eta$
photoproduction from quasifree protons and neutrons bound in the
deuteron. The $2\gamma$ and $3\pi^0$ decay modes were used to optimize
the statistical quality of the data and to estimate systematic
uncertainties. The measurement used the A2 detector setup at the
tagged photon beam of the electron accelerator MAMI in Mainz.
A longitudinally polarized deuterated butanol target was used in
combination with a circularly polarized photon beam from
bremsstrahlung of a longitudinally polarized electron beam. The
reaction products were detected with the electromagnetic
calorimeters Crystal Ball and TAPS, which covered 98% of the full
solid angle. The main systematic uncertainty of the E asymmetry
is related to the measurement of the beam and target
polarizations. The uncertainty of the photon polarization degree
was determined to be ±2.7%. The uncertainty of the target
polarization was estimated as ±10%.
DOI: 10.25549/vercoutere-ouc110637109
title: Reclining elephant molded in clay

description: Glazed clay sculpture of a black elephant reclining with trunk up
DOI: 10.17182/hepdata.132014.v1/t1
title: "tcs" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Inclusive polarized total cross section as a function of photon beam energy.
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t2
title: "dcs_01" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 161. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t3
title: "dcs_02" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 178. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t4
title: "dcs_03" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 196. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t5
title: "dcs_04" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 213. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t6
title: "dcs_05" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 230. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t7
title: "dcs_06" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 247. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t10
title: "dcs_09" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 299. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t11
title: "dcs_10" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 316. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t12
title: "dcs_11" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 333. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t13
title: "dcs_12" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 351. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).
DOI: 10.17182/hepdata.132014.v1/t14
title: "dcs_13" of "Measurement of the helicity dependence for single $\pi^{0}$ photoproduction from the deuteron"

description: Helicity-dependent differential cross section on deuteron at Egamma= 368. MeV
description: A2 Collaboration at MAMI.
The helicity-dependent single $\pi^0$ photoproduction cross section
on the deuteron and the angular dependence of the double
polarisation observable E for the quasi-free single $\pi^0$
production off the proton and the neutron have been measured,
for the first time, from the threshold region up to the photon
energy 1.4 GeV. The experiment was performed at the tagged
photon facility of the MAMI accelerator and used a circularly
polarised photon beam and longitudinally polarised deuteron target.
The reaction products were detected using the large acceptance
Crystal Ball/TAPS calorimeter, which covered 97% of the full solid
angle. Comparing the cross section from the deuteron with the sum
of free nucleon cross sections provides a quantitative estimate of
the effects of the nuclear medium on pion production. In contrast,
comparison of the E helicity asymmetry data from quasi-free
protons off deuterium with data from a free proton target
indicates that nuclear effects do not significantly affect this
observable. As a consequence, it is deduced that the helicity
asymmetry E on a free neutron can be reliably extracted from
measurements on a deuteron in quasi-free kinematics.
Main sources of systematic uncertainties come from the target
polarisation (10%) and from the unpolarised background
subtraction (from 2% up to 10%).