Scientific Commons: A. Airapetian

The momentum and helicity density distributions of the strange quark sea in the nucleon are obtained in leading order from charged-kaon production in deep-inelastic scattering on the deuteron. The...

Evidence for a transverse single-spin asymmetry in leptoproduction of pi(+)pi(-) pairs (2008)

Airapetian, A, Akopov, N, Akopov, Z, Elschenbroich, U, Hommez, B, Maiheu, B, ...

A single-spin asymmetry was measured in the azimuthal distribution of pi(+)pi(-) pairs produced in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target. For the first...

Measurement of azimuthal asymmetries with respect to both beam charge and transverse target polarization in exclusive electroproduction of real photons (2008)

Airapetian, A, Akopov, N, Akopov, Z, Elschenbroich, U, Joosten, S, Maiheu, B, ...

Azimuthal asymmetries in exclusive electroproduction of real photons are measured for the first time with respect to transverse target polarisation, providing new constraints on Generalized Parton...

Measurement of azimuthal asymmetries with respect to both beam charge and transverse target polarization in exclusive electroproduction of real photons (2008)

Airapetian, A., Akopov, N., Akopov, Z., Andrus, A., Aschenauer, E.C., ...

"Azimuthal asymmetries in exclusive electroproduction of real photons are measured for the first time with respect to transverse target polarisation, providing new constraints on Generalized Parton...

Performance of the Electromagnetic Calorimeter of the HERMES Experiment (2007)

Avakian Bianchi, N. Bianchi, G. P. Capitani, E. De Sanctis, P. Di Nezza, A. Fantoni, ...

The performance of the electromagnetic calorimeter of the HERMES experiment is described. The calorimeter consists of 840 radiation resistant F101 lead-glass counters. The response to positrons up to...

The HERMES Spectrometer (2007)

K. Ackerstaff, A. Airapetian, N. Akopov, H. Avakian, V. Andreev, ...

The HERMES experiment is collecting data on inclusive and semi-inclusive deep inelastic scattering of polarised positrons from polarised targets of H, D, and 3 He. These data give information on the...

Beam-Spin Asymmetries in the Azimuthal Distribution of Pion Electroproduction. (2007)

A. Airapetian, DESY Forschung Hochenergiephysik, Z. Akopov, M. Amarian, A. Andrus, E.C. Aschenauer, ...

Journal article

Beam-charge azimuthal asymmetry and deeply virtual Compton scattering (2007)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

Precise determination of the spin structure function g(1) of the proton, deuteron, and neutron (2007)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

Beam-spin asymmetries in the azimuthal distribution of pion electroproduction (2007)

AIRAPETIAN, A, AKOPOV, Z, AMARIAN, M

Hadronization in semi-inclusive deep-inelastic scattering on nuclei (2007)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, ASCHENAUER, EC, AUGUSTYNIAK, W, AVAKIAN, R, ...

Transverse polarization of Lambda and (Lambda)over-bar hyperons in quasireal photoproduction (2007)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Double-hadron leptoproduction in the nuclear medium (2006)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, ANDRUS, A, ASCHENAUER, EC, ...

Longitudinal spin transfer to the Lambda hyperon in semiinclusive deep-inelastic scattering (2006)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

The HERMES polarized hydrogen and deuterium gas target in the HERA electron storage ring (2005)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, ANDRUS, A, ASCHENAUER, EC, ...

Measurement of the tensor structure function b(1) of the deuteron (2005)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Subleading-twist effects in single-spin asymmetries in semi-inclusive deep-inelastic scattering on a longitudinally polarized hydrogen target (2005)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, ANDRUS, A, ASCHENAUER, EC, ...

Single-spin asymmetries in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target (2005)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, ANDRUS, A, ASCHENAUER, EC, ...

Quark helicity distributions in the nucleon for up, down, and strange quarks from semi-inclusive deep-inelastic scattering (2005)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Search for an exotic S =-2, Q =-2 baryon resonance at a mass near 1862 MeV in quasireal photoproduction (2005)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, ANDRUS, A, ASCHENAUER, EC, ...

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering (2004)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized...

Nuclear polarization of molecular hydrogen recombined on a non-metallic surface (2004)

Airapetian, A, Borysenko, Artem

Hard exclusive electroproduction of π+π-pairs (2004)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Hard exclusive electroproduction of pi(+) pi(-) pairs off hydrogen and deuterium targets has been studied by the HERMES experiment at DESY Legendre moments (P-1) and (P-3) of the angular...

Evidence for a narrow |S|=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction (2004)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Evidence for a narrow baryon state is found in quasi-real photoproduction on a deuterium target through the decay channel pK(S)(0) → ppi(+)pi(-). A peak is observed in the pK(S)(0) invariant mass...

Nuclear polarization of molecular hydrogen recombined on a non-metallic surface (2004)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Evidence for a narrow vertical bar S vertical bar=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction (2004)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering (2004)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Hard exclusive electroproduction of pi(+)pi(-) pairs (2004)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Nuclear polarization of molecular hydrogen recombined on a non-metallic surface (2004)

Airapetian, A, Borysenko, Artem

Nuclear polarization of molecular hydrogen recombined on a non-metallic surface (2004)

Airapetian, A, Borysenko, Artem

Double-spin asymmetries in the cross section of rho /sup 0/ and phi production at intermediate energies (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Double-spin asymmetries in the cross section of electroproduction of rho /sup 0/ and phi mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in...

Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Single-spin asymmetries have been measured for semi-inclusive electroproduction of pi /sup +/, pi /sup -/, pi /sup 0/ and K/sup +/ mesons in deep-inelastic scattering off a longitudinally polarised...

Evidence for quark-hadron duality in the proton spin asymmetry A1 (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Aschenauer, E.C., ...

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were...

Q2 dependence of nuclear transparency for exclusive rho0 production (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to...

Q2 dependence of nuclear transparency for exclusive rho0 production (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to...

Quark fragmentation to pi(+/-), pi(0), K-+/-, p and (p)over-bar in the nuclear environment (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

The influence of the nuclear medium on lepto-production of hadrons was studied in the HERMES experiment at DESY in semi- inclusive deep-inelastic scattering of 27.6 GeV positrons off deuterium,...

The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the deuteron, proton and neutron (2003)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Aschenauer, E.C., ...

The Gerasimov-Drell-Hearn (GDH) sum rule connects the anomalous contribution to the magnetic moment of the target nucleus with an energy-weighted integral of the difference of the helicity- dependent...

Quark fragmentation to pi(+/-), pi(0), K-+/-, p and (p)over-bar in the nuclear environment (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

Nuclear effects on R = sigma(L)/sigma(T) in deep-inelastic scattering (vol 475, pg 386, 2000) (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ANDRUS, A, ...

The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the deuteron, proton and neutron (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z, AMARIAN, M, AMMOSOV, VV, ASCHENAUER, EC, ...

Evidence for quark-hadron duality in the proton spin asymmetry A(1) (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

Q(2) dependence of nuclear transparency for exclusive rho(0) production (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

Double-spin asymmetries in the cross section of rho(0) and phi production at intermediate energies (2003)

AIRAPETIAN, A, AKOPOV, N, AKOPOV, Z

Single-spin azimuthal asymmetry in exclusive electroproduction of pi /sup +/ mesons (2002)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

A single-spin asymmetry in the distribution of exclusively produced pi /sup +/ mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the...

Single-spin azimuthal asymmetry in exclusive electroproduction of pi(+) mesons (2002)

Airapetian, A, Akopov, N, Akopov, Z, Hommez, B, Ryckbosch, Dirk, Tytgat, Michael, ...

A single-spin asymmetry in the distribution of exclusively produced pi(+) mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the...

Measurement of longitudinal spin transfer to Lambda hyperons in deep-inelastic lepton scattering (2001)

Airapetian, A., Akopov, N., Amarian, M., Aschenauer, E.C., Avakian, H., Avakian, R., ...

Spin transfer in deep-inelastic Lambda electroproduction has been studied with the HERMES detector using the 27.6 GeV polarized positron beam in the DESY HERA storage ring. For an average fractional...

Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering (2001)

Airapetian, A, Akopov, N., Akopov, Z., Amarian, M, Aschenauer, E.C., Avakian, H., ...

A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off...

Double-spin asymmetry in the cross section for exclusive rho0 production in lepton-proton scattering (2001)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Arrington, J., Aschenauer, E.C., ...

Evidence for a positive longitudinal double-spin asymmetry (A/sub 1//sup rho /)=0.24+or-0.11/sub stat/+or-0.02/sub syst/ in the cross section for exclusive diffractive rho /sup 0/(770) vector-meson...

Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering (2001)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

Hadron formation in deep-inelastic positron scattering in a nuclear environment (2001)

Airapetian, A., Akopov, N., Akopov, Z., Akushevich, I., Amarian, T., Arrington, J., ...

The influence of the nuclear medium on the production of charged hadrons in semi-inclusive deep-inelastic scattering has been studied by the HERMES experiment at DESY using a 27.5 GeV positron beam....

Measurement of the beam-spin azimuthal asymmetry associated with deeply-virtual compton scattering (2001)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

The beam spin asymmetry in hard electroproduction of photons was measured in the missing-mass (Mx) range upto 7 GeV. A nonzero asymmetry was observed in the exclusive domain for Mx [less-than or...

Multiplicity of charged and neutral pions in deep-inelastic scattering of 27.5 GeV positrons on hydrogen (2001)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Arrington, J., Aschenauer, E.C., ...

Measurements of the individual multiplicities of pi /sup +/, pi /sup -/ and pi /sup 0/ produced in the deep-inelastic scattering of 27.5 GeV positrons on hydrogen are presented. The average charged...

Multiplicity of charged and neutral pions in deep-inelastic scattering of 27.5 GeV positrons on hydrogen. (2001)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Hadron formation in deep-inelastic positron scattering in a nuclear environment. (2001)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Double-spin asymmetry in the cross section for exclusive rho(0) production in lepton-proton scattering. (2001)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering - art. no. 097101. (2001)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Measurement of longitudinal spin transfer to Lambda hyperons in deep-inelastic lepton scattering - art. no. 112005. (2001)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Measurement of the Beam-Spin Azimuthal Asymmetry Associated with Deeply-Virtual Compton Scattering (2001)

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E. C.

The Q^2-dependence of the Generalised Gerasimov-Drell-Hearn Integral for the Proton (2000)

Airapetian, A.

The dependence on Q^2 (the negative square of the 4-momentum of the exchanged virtual photon) of the generalised Gerasimov-Drell-Hearn integral for the proton has been measured in the range 1.2 GeV^2...

Measurement of the spin asymmetry in the photoproduction of pairs of high-p(T) hadrons at HERMES. (2000)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

The Q2-dependence of the Generalised Gerasimov-Drell-Hearn Integral for the Proton. (2000)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Evidence for a single-spin azimuthal asymmetry in semi-inclusive pion electroproduction. (2000)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Erratum to K. Ackerstaff et al. (2000)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, HOMMEZ, B

Exclusive leptoproduction of p(0) mesons from hydrogen at intermediate virtual photon energies. (2000)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the proton. (2000)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, HOMMEZ, B

Exclusive Leptoproduction of (2000)

Mesons From Hydrogen, A. Airapetian, N. Akopov, I. Akushevich, M. Amarian, J. Arrington, ...

. Measurements of the cross section for exclusive virtual-photoproduction of ae 0 mesons from hydrogen are reported. The data were collected by the HERMES experiment using 27.5 GeV positrons incident...

Measurement of Angular Distributions and (2000)

In Diractive Electroproduction, A. Airapetian, N. Akopov, M. Amarian, H. Avakian

. Production and decay angular distributions were extracted from measurements of exclusive electroproduction of the # 0 (770) meson over a range in the virtual photon negative four-momentum squared...

Observation of a Single-Spin Azimuthal Asymmetry in Semi-Inclusive Pion Electro-Production (1999)

Airapetian, A.

Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal...

Measurement of the Spin Asymmetry in the Photoproduction of Pairs of High-pT Hadrons at HERMES (1999)

Airapetian, A.

We present a measurement of the longitudinal spin asymmetry A_|| in photoproduction of pairs of hadrons with high transverse momentum p_T. Data were accumulated by the HERMES experiment using a 27.5...

Observation of a coherence length effect in exclusive ρ(0) electroproduction (1999)

Ackerstaff, K., Airapetian, A., Akopov, N., Akushevich, I., Amarian, M., Aschenauer, E. C., ...

Exclusive incoherent electroproduction of the ρ0(770) meson from 1H, 2H, 3He, and 14N targets has been studied by the HERMES experiment at squared four-momentum transfer Q^2>0.4 GeV^2 and positron...

Beam-induced nuclear depolarization in a gaseous polarized-hydrogen target (1999)

Ackerstaff, K., Airapetian, A., Akopov, N., Amarian, M., Aschenauer, E. C., Avakian, H., ...

Spin-polarized atomic hydrogen is used as a gaseous polarized-proton target in high-energy and nuclear-physics experiments operating with internal beams in storage rings. When such beams are intense...

ATLAS detector and physics performance technical design report (1999)

ATLAS Collaboration, Airapetian, A, Apsimon, RJ, Baines, JT, Baynham, DE, Botterill, DR, ...

Physics Performance Technical Design Report, CERN-LHCC-98-13

Flavor asymmetry of the light quark sea from semi-inclusive deep-inelastic scattering (1998)

Ackerstaff, K., Airapetian, A., Akopov, N., Akushevich, I., Amarian, M., Ashenauer, E. C., ...

The flavor asymmetry of the light quark sea of the nucleon is determined in the kinematic range 0.02 < x < 0.3 and 1 < Q(2) < 10 GeV2 for the first time from semi-inclusive deep-inelastic scattering....

Measurement of the Proton Spin Structure Function g1p with a Pure Hydrogen Target (1998)

Airapetian, A.

A measurement of the proton spin structure function g1p(x,Q^2) in deep-inelastic scattering is presented. The data were taken with the 27.6 GeV longitudinally polarised positron beam at HERA incident...

ATLAS Pixel Detector Technical Design Report (1998)

ATLAS Collaboration, Airapetian, A, Apsimon, R J, Baines, J T, Baynham, D E, Botterill, D R, ...

CERN-LHCC-98-13

Measurement of the proton spin structure function g(1)(p) with a pure hydrogen target. (1998)

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

The HERMES Spectrometer (1998)

Ackerstaff Airapetian Akopov, K. Ackerstaff, A. Airapetian, N. Akopov, M. Amarian, V. Andreev, ...

The HERMES experiment is collecting data on inclusive and semi-inclusive deep inelastic scattering of polarised positrons from polarised targets of H, D, and 3 He. These data give information on the...

ATLAS Inner Detector Technical Design Report (1997)

ATLAS Collaboration, Airapetian, A, Apsimon, R J, Baines, J T, Baynham, D E, Botterill, D R, ...

CERN-LHCC-97-16

ATLAS calorimeter performance (1996)

ATLAS Collaboration, Airapetian, A, Grabsky, V, Hakopian, H, Vartapetian, A, Fares, F, ...

ATLAS computing technical proposal (1996)

ATLAS Collaboration, Airapetian, A, Grabsky, V, Hakopian, H, Vartapetian, A, Fares, F, ...

ATLAS computing technical proposal (1996)

Airapetian, A., Grabsky, V., Hakopian, H., Vartapetian, A., Fares, F., Moorhead, G.F., ...

ATLAS calorimeter performance (1996)

Airapetian, A., Grabsky, V., Hakopian, H., Vartapetian, A., Fares, F., Moorhead, G.F., ...

ATLAS computing technical proposal (1996)

Airapetian, A., Grabsky, V., Hakopian, H., Vartapetian, A., Fares, F., Moorhead, G.F., ...

ATLAS calorimeter performance (1996)

Airapetian, A., Grabsky, V., Hakopian, H., Vartapetian, A., Fares, F., Moorhead, G.F., ...

Double-spin asymmetries in the cross section of rho /sup 0/ and phi production at intermediate energies

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Double-spin asymmetries in the cross section of electroproduction of rho /sup 0/ and phi mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in...

Double-spin asymmetry in the cross section for exclusive rho0 production in lepton-proton scattering

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Arrington, J., Aschenauer, E.C., ...

Evidence for a positive longitudinal double-spin asymmetry (A/sub 1//sup rho /)=0.24+or-0.11/sub stat/+or-0.02/sub syst/ in the cross section for exclusive diffractive rho /sup 0/(770) vector-meson...

Evidence for quark-hadron duality in the proton spin asymmetry A1

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Aschenauer, E.C., ...

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were...

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized...

Hadron formation in deep-inelastic positron scattering in a nuclear environment

Airapetian, A., Akopov, N., Akopov, Z., Akushevich, I., Amarian, T., Arrington, J., ...

The influence of the nuclear medium on the production of charged hadrons in semi-inclusive deep-inelastic scattering has been studied by the HERMES experiment at DESY using a 27.5 GeV positron beam....

Measurement of longitudinal spin transfer to Lambda hyperons in deep-inelastic lepton scattering

Airapetian, A., Akopov, N., Amarian, M., Aschenauer, E.C., Avakian, H., Avakian, R., ...

Spin transfer in deep-inelastic Lambda electroproduction has been studied with the HERMES detector using the 27.6 GeV polarized positron beam in the DESY HERA storage ring. For an average fractional...

Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Single-spin asymmetries have been measured for semi-inclusive electroproduction of pi /sup +/, pi /sup -/, pi /sup 0/ and K/sup +/ mesons in deep-inelastic scattering off a longitudinally polarised...

Measurement of the beam-spin azimuthal asymmetry associated with deeply-virtual compton scattering

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

The beam spin asymmetry in hard electroproduction of photons was measured in the missing-mass (Mx) range upto 7 GeV. A nonzero asymmetry was observed in the exclusive domain for Mx [less-than or...

Multiplicity of charged and neutral pions in deep-inelastic scattering of 27.5 GeV positrons on hydrogen

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Arrington, J., Aschenauer, E.C., ...

Measurements of the individual multiplicities of pi /sup +/, pi /sup -/ and pi /sup 0/ produced in the deep-inelastic scattering of 27.5 GeV positrons on hydrogen are presented. The average charged...

Q2 dependence of nuclear transparency for exclusive rho0 production

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to...

Q2 dependence of nuclear transparency for exclusive rho0 production

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to...

Quark fragmentation to pi(+/-), pi(0), K-+/-, p and (p)over-bar in the nuclear environment

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

The influence of the nuclear medium on lepto-production of hadrons was studied in the HERMES experiment at DESY in semi- inclusive deep-inelastic scattering of 27.6 GeV positrons off deuterium,...

Single-spin azimuthal asymmetry in exclusive electroproduction of pi /sup +/ mesons

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

A single-spin asymmetry in the distribution of exclusively produced pi /sup +/ mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the...

Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering

Airapetian, A, Akopov, N., Akopov, Z., Amarian, M, Aschenauer, E. C., Avakian, H., ...

A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off...

The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the deuteron, proton and neutron

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Aschenauer, E.C., ...

The Gerasimov-Drell-Hearn (GDH) sum rule connects the anomalous contribution to the magnetic moment of the target nucleus with an energy-weighted integral of the difference of the helicity- dependent...

Hard exclusive electroproduction of π+π-pairs

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Hard exclusive electroproduction of pi(+) pi(-) pairs off hydrogen and deuterium targets has been studied by the HERMES experiment at DESY Legendre moments (P-1) and (P-3) of the angular...

Evidence for a narrow |S|=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Evidence for a narrow baryon state is found in quasi-real photoproduction on a deuterium target through the decay channel pK(S)(0) → ppi(+)pi(-). A peak is observed in the pK(S)(0) invariant mass...

Double-spin asymmetries in the cross section of rho /sup 0/ and phi production at intermediate energies

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Double-spin asymmetries in the cross section of electroproduction of rho /sup 0/ and phi mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in...

Double-spin asymmetry in the cross section for exclusive rho0 production in lepton-proton scattering

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Arrington, J., Aschenauer, E.C., ...

Evidence for a positive longitudinal double-spin asymmetry (A/sub 1//sup rho /)=0.24+or-0.11/sub stat/+or-0.02/sub syst/ in the cross section for exclusive diffractive rho /sup 0/(770) vector-meson...

Evidence for quark-hadron duality in the proton spin asymmetry A1

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Aschenauer, E.C., ...

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were...

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized...

Hadron formation in deep-inelastic positron scattering in a nuclear environment

Airapetian, A., Akopov, N., Akopov, Z., Akushevich, I., Amarian, T., Arrington, J., ...

The influence of the nuclear medium on the production of charged hadrons in semi-inclusive deep-inelastic scattering has been studied by the HERMES experiment at DESY using a 27.5 GeV positron beam....

Measurement of longitudinal spin transfer to Lambda hyperons in deep-inelastic lepton scattering

Airapetian, A., Akopov, N., Amarian, M., Aschenauer, E.C., Avakian, H., Avakian, R., ...

Spin transfer in deep-inelastic Lambda electroproduction has been studied with the HERMES detector using the 27.6 GeV polarized positron beam in the DESY HERA storage ring. For an average fractional...

Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Single-spin asymmetries have been measured for semi-inclusive electroproduction of pi /sup +/, pi /sup -/, pi /sup 0/ and K/sup +/ mesons in deep-inelastic scattering off a longitudinally polarised...

Measurement of the beam-spin azimuthal asymmetry associated with deeply-virtual compton scattering

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

The beam spin asymmetry in hard electroproduction of photons was measured in the missing-mass (Mx) range upto 7 GeV. A nonzero asymmetry was observed in the exclusive domain for Mx [less-than or...

Multiplicity of charged and neutral pions in deep-inelastic scattering of 27.5 GeV positrons on hydrogen

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Arrington, J., Aschenauer, E.C., ...

Measurements of the individual multiplicities of pi /sup +/, pi /sup -/ and pi /sup 0/ produced in the deep-inelastic scattering of 27.5 GeV positrons on hydrogen are presented. The average charged...

Q2 dependence of nuclear transparency for exclusive rho0 production

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to...

Q2 dependence of nuclear transparency for exclusive rho0 production

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to...

Quark fragmentation to pi(+/-), pi(0), K-+/-, p and (p)over-bar in the nuclear environment

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

The influence of the nuclear medium on lepto-production of hadrons was studied in the HERMES experiment at DESY in semi- inclusive deep-inelastic scattering of 27.6 GeV positrons off deuterium,...

Single-spin azimuthal asymmetry in exclusive electroproduction of pi /sup +/ mesons

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E.C., Avakian, H., ...

A single-spin asymmetry in the distribution of exclusively produced pi /sup +/ mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the...

Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering

Airapetian, A, Akopov, N., Akopov, Z., Amarian, M, Aschenauer, E. C., Avakian, H., ...

A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off...

The Q(2)-dependence of the generalised Gerasimov-Drell-Hearn integral for the deuteron, proton and neutron

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Aschenauer, E.C., ...

The Gerasimov-Drell-Hearn (GDH) sum rule connects the anomalous contribution to the magnetic moment of the target nucleus with an energy-weighted integral of the difference of the helicity- dependent...

Hard exclusive electroproduction of π+π-pairs

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Hard exclusive electroproduction of pi(+) pi(-) pairs off hydrogen and deuterium targets has been studied by the HERMES experiment at DESY Legendre moments (P-1) and (P-3) of the angular...

Evidence for a narrow |S|=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., ...

Evidence for a narrow baryon state is found in quasi-real photoproduction on a deuterium target through the decay channel pK(S)(0) → ppi(+)pi(-). A peak is observed in the pK(S)(0) invariant mass...

ρ0 Transverse Target Spin Asymmetry at HERMES 2007-05-21 - 2007-05-24

A. Airapetian, DESY Forschung Hochenergiephysik

Conference presentation

Compton Polarimetery at HERA, more than 10 years of operation 2007-08-23 - 2007-08-24

A. Airapetian, DESY Forschung Hochenergiephysik

Conference presentation

Diffractive Slope Extraction of Exclusive ρ0L and ρ0T at HERMES 2008-10-23 - 2008-10-26

B. Ball, DESY Forschung Hochenergiephysik, A. Airapetian, B. Marianski

Conference presentation

First Observation of a Single-Spin Azimuthal Asymmetry in Semi-Inclusive Pion Electro-Production.

AIRAPETIAN, A, Ryckbosch, Dirk, Tytgat, Michaël, Van De Vyver, Robert, Hommez, Brecht

Measurment of Longitudinal Spin Transfer to Lambda Hyperons in Deep Inelastic Lepton Scattering.