F. Afzal

activity

20152025

η

and

η^{'}

photoproduction at MAMI

55 citations · 687 across the 47 of their papers we have counts for

collaborators

47 papers

hep-ex2025

Search for the $Y (2175)$ in the photoproduction cross section measurement of $γ p \to ϕ π^{+} π^{-} p$ at GlueX

GlueX Collaboration

Based on 334 pb $^{- 1}$ of photoproduction data collected with the GlueX detector at Jefferson Lab, we have measured for the first time the cross section of the exclusive reaction $…

hep-ex2025

New high-statistics measurement of the $π^{0} \to e^{+} e^{-} γ$ Dalitz decay at the Mainz Microtron

S. Prakhov, L. Heijkenskjöld, S. Abt +69

The Dalitz decay $π^{0} \to e^{+} e^{-} γ$ has been measured with the highest statistical accuracy obtained so far in the $γ p \to π^{0} p$ reaction with the A2 tagged-photon facility at the M…

hep-ex2025

Baryon-antibaryon photoproduction cross sections off the proton

GlueX Collaboration, F. Afzal, M. Albrecht +137

The GlueX experiment at Jefferson Lab has observed $p p ˉ$ and, for the first time, $Λ Λ ˉ$ and $p Λ ˉ$ photoproduction from a proton target at photon energies up to 11.6 GeV.…

nucl-ex2025

Measurement of the Total Compton Scattering Cross Section between 6.5 and 11 GeV

GlueX Collaboration, F. Afzal, C. S. Akondi +148

The total cross section for Compton scattering off atomic electrons, $γ + e \to γ^{'} + e^{'}$ , was measured using photons with energies between 6.5 and 11.1 GeV incident on a $^{9}$ Be t…

nucl-ex2024

Measurement of Spin-Density Matrix Elements in $Δ^{++} (1232)$ photoproduction

F. Afzal, C. S. Akondi, M. Albrecht +146

We measure the spin-density matrix elements (SDMEs) of the $Δ^{++} (1232)$ in the photoproduction reaction $γ p \to π^{-} Δ^{++} (1232)$ with the GlueX experiment in Hall D at Jefferson…

nucl-ex2024★ 6 cited

Upper Limit on the Photoproduction Cross Section of the Spin-Exotic $π_{1} (1600)$

GlueX Collaboration, F. Afzal, C. S. Akondi +147

The spin-exotic hybrid meson $π_{1} (1600)$ is predicted to have a large decay rate to the $ω π π$ final state. Using 76.6~pb $^{- 1}$ of data collected with the GlueX detector, we meas…

nucl-ex2024

First measurement using elliptically polarized photons of the double-polarization observable $E$ for $γ p \to p π^{0}$ and $γ p \to n π^{+}$

A2 Collaboration, F. Afzal, K. Spieker +74

We report the measurement of the helicity asymmetry $E$ for the $p π^{0}$ and $n π^{+}$ final states using, for the first time, an elliptically polarized photon beam in combination with…

nucl-ex2023

Evaluation of the E2/M1 ratio in the $N \to Δ (1232)$ transition from the $γ p \to p π^{0}$ reaction

E. Mornacchi, P. Pedroni, F. Afzal +59

A new data set for the helicity-dependent differential cross section of the single-meson photoproduction reaction $γ p \to p π^{0}$ was obtained for the photon energy interval 150-4…

nucl-ex2023★ 2 cited

Helicity dependent cross sections for the photoproduction of $π^{0} π^{\pm}$ pairs from quasi-free nucleons

A2 Collaboration, D. Ghosal, V. Sokhoyan +71

Photoproduction of $π^{0} π^{\pm}$ -pairs from quasifree nucleons bound in the deuteron has been investigated to study the helicity dependence of this reaction. Measurements with a liq…

nucl-ex2023★ 16 cited

Measurement of Spin-Density Matrix Elements in $ρ (770)$ Production with a Linearly Polarized Photon Beam at $E_{γ} = 8.2 - 8.8 GeV$

GlueX Collaboration, S. Adhikari, F. Afzal +150

The GlueX experiment at Jefferson Lab studies photoproduction of mesons using linearly polarized $8.5 GeV$ photons impinging on a hydrogen target which is contained within…

physics.ins-det2023

The new APD-Based Readout of the Crystal Barrel Calorimeter -- An Overview

TAPS Collaboration, C. Honisch, P. Klassen +47

The Crystal Barrel is an electromagnetic calorimeter consisting of 1380 CsI(Tl) scintillators, and is currently installed at the CBELSA/TAPS experiment where it is used to detect d…

nucl-ex2022

Neutron polarisation transfer, $C_{x^{'}}^{n}$ , in $π^{+}$ photoproduction off the proton

M. Bashkanov, D. P. Watts, S. J. D. Kay +63

We report a first measurement of the double-polarisation observable, $C_{x^{'}}$ , in $π^{+}$ photoproduction off the proton. The $C_{x^{'}}$ double-polarisation observable represents the t…

hep-ex2022

Target and beam-target asymmetries for the $γ p \to π^{0} π^{0} p$ reaction

S. Garni, V. L. Kashevarov, A. Fix +81

Background: Photoproduction of pion pairs allows to study sequential decays of nucleon resonances via excited intermediate states. Such decays are important e.g. for states which i…

nucl-ex2022★ 4 cited

Polarization observables in double neutral pion photoproduction

TAPS Collaboration, T. Seifen, J. Hartmann +73

Measurements of target asymmetries and double-polarization observables for the reaction $γ p \to p π^{0} π^{0}$ are reported. The data were taken with the CBELSA/TAPS experiment at the ELS…

nucl-ex2022★ 1 cited

Measurement of the helicity dependence for single $π^{0}$ photoproduction from the deuteron

The A2 collaboration, F. Cividini, M. Dieterle +72

The helicity-dependent single $π^{0}$ photoproduction cross section on the deuteron and the angular dependence of the double polarisation observable $E$ for the quasi-free single $…

nucl-ex2021★ 11 cited

Observation of a structure in the M $_{p η}$ invariant mass distribution near 1700 MeV/ $c^{2}$ in the $γ p \to p π^{0} η$ reaction

V. Metag, M. Nanova, J. Hartmann +74

The reaction $γ p \to p π^{0} η$ has been studied with the CBELSA/TAPS detector at the electron stretcher accelerator ELSA in Bonn for incident photon energies from threshold…

nucl-ex2021

Measurement of Compton scattering at MAMI for the extraction of the electric and magnetic polarizabilities of the proton

A2 Collaboration, E. Mornacchi, P. P. Martel +65

A precise measurement of the differential cross-sections $d σ / d Ω$ and the linearly polarized photon beam asymmetry $Σ_{3}$ for Compton scattering on the proton below pion threshold ha…

nucl-ex2021★ 2 cited

Single $π^{0}$ Production Off Neutrons Bound in Deuteron with Linearly Polarized Photons

C. Mullen, S. Gardner, D. I. Glazier +79

The quasifree $γ d \to π^{0} n (p)$ photon beam asymmetry, $Σ$ , has been measured at photon energies, $E_{γ}$ , from 390 to 610 MeV, corresponding to center of mass energy fr…

nucl-th2020★ 9 cited

Minimal complete sets for two pseudoscalar meson photoproduction

Philipp Kroenert, Yannick Wunderlich, Farah Afzal +1

For photoproduction reactions with final states consisting of two pseudoscalar mesons and a spin-1/2 baryon, 8 complex amplitudes need to be determined uniquely. A modified version…

nucl-ex2020★ 20 cited

Observation of the $p η^{'}$ Cusp in the New Precise Beam Asymmetry $Σ$ Data for $γ p \to p η$

TAPS Collaboration

Data on the beam asymmetry $Σ$ in the photoproduction of $η$ mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from $W =$ 1748 MeV to $W =$ …

nucl-ex2020★ 9 cited

Helicity-dependent cross sections for the photoproduction of $π^{0}$ pairs from nucleons

M. Dieterle, L. Witthauer, A. Fix +88

The double-polarization observable $E$ and helicity-dependent cross sections $σ_{1/2}$ , $σ_{3/2}$ have been measured for the photoproduction of $π^{0}$ pairs off quasi-free protons a…

nucl-th2020★ 12 cited

Moravcsik's theorem on complete sets of polarization observables reexamined

Y. Wunderlich, P. Kroenert, F. Afzal +1

We revisit Moravcsik's theorem on the unique extraction of amplitudes from polarization observables, which has been originally published in 1985. The proof is (re-) written in a mo…

nucl-ex2019★ 20 cited

Signatures of the $d^{*} (2380)$ hexaquark in d( $γ$ , $p n$ )

M. Bashkanov, D. P. Watts, S. J. D. Kay +74

We report a measurement of the spin polarisation of the recoiling neutron in deuterium photodisintegration, utilising a new large acceptance polarimeter within the Crystal Ball at…

nucl-ex2019★ 26 cited

New data on $γ p \to η p$ with polarized photons and protons and their implications for $N^{*} \to N η$ decays

J. Müller, J. Hartmann, M. Grüner +86

The polarization observables $T, E, P, H$ , and $G$ in photoproduction of $η$ mesons off protons are measured for photon energies from threshold to $W = 2400$ MeV ( $T$ ), 2280 MeV ($E…

Search for the Y(2175) in the photoproduction cross section measurement of γp→ϕπ+π−p at GlueX

New high-statistics measurement of the π0→e+e−γ Dalitz decay at the Mainz Microtron

Baryon-antibaryon photoproduction cross sections off the proton

Measurement of the Total Compton Scattering Cross Section between 6.5 and 11 GeV

Measurement of Spin-Density Matrix Elements in Δ++(1232) photoproduction

Upper Limit on the Photoproduction Cross Section of the Spin-Exotic π1​(1600)

First measurement using elliptically polarized photons of the double-polarization observable E for γp→pπ0 and γp→nπ+

Evaluation of the E2/M1 ratio in the N→Δ(1232) transition from the γ​p​→pπ0 reaction

Helicity dependent cross sections for the photoproduction of π0π± pairs from quasi-free nucleons

Measurement of Spin-Density Matrix Elements in ρ(770) Production with a Linearly Polarized Photon Beam at Eγ​=8.2−8.8GeV

The new APD-Based Readout of the Crystal Barrel Calorimeter -- An Overview

Neutron polarisation transfer, Cx′n​, in π+ photoproduction off the proton

Target and beam-target asymmetries for the γp→π0π0p reaction

Polarization observables in double neutral pion photoproduction

Measurement of the helicity dependence for single π0 photoproduction from the deuteron

Observation of a structure in the Mpη​ invariant mass distribution near 1700 MeV/c2 in the γp→pπ0η reaction

Measurement of Compton scattering at MAMI for the extraction of the electric and magnetic polarizabilities of the proton

Single π0 Production Off Neutrons Bound in Deuteron with Linearly Polarized Photons

Minimal complete sets for two pseudoscalar meson photoproduction

Observation of the pη′ Cusp in the New Precise Beam Asymmetry Σ Data for γp→pη

Helicity-dependent cross sections for the photoproduction of π0 pairs from nucleons

Moravcsik's theorem on complete sets of polarization observables reexamined

Signatures of the d∗(2380) hexaquark in d(γ,pn)

New data on γ​p​→ηp with polarized photons and protons and their implications for N∗→Nη decays

Search for the $Y (2175)$ in the photoproduction cross section measurement of $γ p \to ϕ π^{+} π^{-} p$ at GlueX

New high-statistics measurement of the $π^{0} \to e^{+} e^{-} γ$ Dalitz decay at the Mainz Microtron

Measurement of Spin-Density Matrix Elements in $Δ^{++} (1232)$ photoproduction

Upper Limit on the Photoproduction Cross Section of the Spin-Exotic $π_{1} (1600)$

First measurement using elliptically polarized photons of the double-polarization observable $E$ for $γ p \to p π^{0}$ and $γ p \to n π^{+}$

Evaluation of the E2/M1 ratio in the $N \to Δ (1232)$ transition from the $γ p \to p π^{0}$ reaction

Helicity dependent cross sections for the photoproduction of $π^{0} π^{\pm}$ pairs from quasi-free nucleons

Measurement of Spin-Density Matrix Elements in $ρ (770)$ Production with a Linearly Polarized Photon Beam at $E_{γ} = 8.2 - 8.8 GeV$

Neutron polarisation transfer, $C_{x^{'}}^{n}$ , in $π^{+}$ photoproduction off the proton

Target and beam-target asymmetries for the $γ p \to π^{0} π^{0} p$ reaction

Measurement of the helicity dependence for single $π^{0}$ photoproduction from the deuteron

Observation of a structure in the M $_{p η}$ invariant mass distribution near 1700 MeV/ $c^{2}$ in the $γ p \to p π^{0} η$ reaction

Single $π^{0}$ Production Off Neutrons Bound in Deuteron with Linearly Polarized Photons

Observation of the $p η^{'}$ Cusp in the New Precise Beam Asymmetry $Σ$ Data for $γ p \to p η$

Helicity-dependent cross sections for the photoproduction of $π^{0}$ pairs from nucleons

Signatures of the $d^{*} (2380)$ hexaquark in d( $γ$ , $p n$ )

New data on $γ p \to η p$ with polarized photons and protons and their implications for $N^{*} \to N η$ decays