# COMPASS Conference Proceedings

Derniers ajouts:
2017-02-25
07:55
 The $t$-dependence of the pure DVCS cross section at COMPASS / Joerg, Philipp (Freiburg U.) /COMPASS Collaboration The key reactions to study the Generalised Parton Distributions are Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP). At COMPASS, these processes are investigated using a high intensity muon beam with a momentum of 160\,GeV/c and a 2.5\,m-long liquid hydrogen target. [...] arXiv:1702.06315.- SISSA, 2016-10-10 - 7 p. - Published in : PoS: DIS2016 (2016) , pp. 235 Fulltext: PDF; Preprint: PDF; External links: PoS server; 00007 COMPASS results for the t-slope parameter (\textbf{left}) and the extracted transverse size of the partonic distribution of the nucleon (\textbf{right}), compared with previous HERA measurements.; 00003 Exclusivity variables: The whole Monte Carlo estimate is shown in red while in grey only the $\pi^0$ contamination is shown. The variables $\Delta \varphi$, $\Delta p_{\bot}$ and $M_X^2$ are defined in equation \ref{eq_phi}-\ref{eq_m} while $\Delta z_{A}$ encodes a reverse vertex pointing. The blue dotted lines indicate the applied cuts.; 00006 COMPASS results for the t-slope parameter (\textbf{left}) and the extracted transverse size of the partonic distribution of the nucleon (\textbf{right}), compared with previous HERA measurements.; 00001 Exclusivity variables: The whole Monte Carlo estimate is shown in red while in grey only the $\pi^0$ contamination is shown. The variables $\Delta \varphi$, $\Delta p_{\bot}$ and $M_X^2$ are defined in equation \ref{eq_phi}-\ref{eq_m} while $\Delta z_{A}$ encodes a reverse vertex pointing. The blue dotted lines indicate the applied cuts.; 00002 Exclusivity variables: The whole Monte Carlo estimate is shown in red while in grey only the $\pi^0$ contamination is shown. The variables $\Delta \varphi$, $\Delta p_{\bot}$ and $M_X^2$ are defined in equation \ref{eq_phi}-\ref{eq_m} while $\Delta z_{A}$ encodes a reverse vertex pointing. The blue dotted lines indicate the applied cuts.; 00000 Exclusivity variables: The whole Monte Carlo estimate is shown in red while in grey only the $\pi^0$ contamination is shown. The variables $\Delta \varphi$, $\Delta p_{\bot}$ and $M_X^2$ are defined in equation \ref{eq_phi}-\ref{eq_m} while $\Delta z_{A}$ encodes a reverse vertex pointing. The blue dotted lines indicate the applied cuts.; 00005 The $t$-differential DVCS cross section as a function of $t$; 00004 Acceptance correction factors as a function of $t$, $Q^2$ and $\nu$.; Fulltext In : 24th International Workshop on Deep Inelastic Scattering and related subjects, Hamburg, Germany, 11 - 15 Apr 2016, pp.235

2017-02-25
07:55
 Measurement of the exclusive ${\pi}^0$ muoproduction cross section at COMPASS / Gorzellik, Matthias (Freiburg U.) At COMPASS DVCS and DVMP processes are studied in order to probe the partonic structure of the nucleon by constraining GPD models. [...] arXiv:1702.06293. - 4 p. Preprint

2017-02-10
07:37
 COMPASS measurement of the $P_T$ weighted Sivers asymmetry / Bradamante, Franco (INFN, Trieste) The SIDIS transverse spin asymmetries weighted with powers of $P_T$, the hadron transverse momentum in the $\gamma N$ reference system,have been introduced already twenty years ago and are considered quite interesting. [...] arXiv:1702.00621. - 4 p. Preprint

2016-10-08
07:48
 The spectrum of light isovector mesons with $C=+1$ from the COMPASS experiment / Paul, Stephan (Munich, Tech. U.) Based on the largest event sample of diffractively produced $\pi^-\pi^-\pi^+$, obtained by a pion beam of $190~\rm{GeV/c}$ momentum, the COMPASS collaboration has performed the most advanced partial wave analysis on multi-body final states, using the isobar model. The large number of waves included in the analysis reduces truncation effects. [...] arXiv:1610.01231.- 2016 - 9 p. - Published in : JPS Conf. Proc. 13 (2017) 010018 Fulltext: PDF; External link: Preprint In : Meson-Nucleon Physics and the Structure of the Nucleon, Kyoto, Japan, 25 - 30 Jul 2016, pp.010018

2016-09-29
01:12
 Photons interacting with Hadrons at COMPASS / Friedrich, Jan Michael (Technische Universitaet Muenchen (DE)) /COMPASS NA58 Collaboration COMPASS is a multi-purpose experiment operated at CERN for investigations of the strong interaction from low to medium energy scales. At low energies, photon-pion interactions provide input for understanding the effective dynamics of strongly bound states of quarks and gluons, most prominently the recent measurement of the polarisability of the charged pion. [...] COMPASS-PROC-2016-001.- Geneva : CERN, 2015 - 8. Fulltext: PDF;

2016-09-28
07:58
 Extraction of the $\pi^+\pi^-$ Subsystem in Diffractively Produced $\pi^-\pi^+\pi^-$ at COMPASS / Krinner, Fabian (Munich, Tech. U.) /for the COMPASS collaboration The COMPASS experiment at CERN has collected a large data sample of 50 million diffractively produced $\pi^-\pi^+\pi^-$ events using a $190\,$GeV$/c$ negatively charged hadron beam. The partial-wave analysis (PWA) of these high-precision data reveals previously unseen details. [...] arXiv:1609.08514.- 2017 - 5 p. - Published in : JPS Conf.Proc. 13 (2017) 020028 Preprint: PDF; External link: Preprint In : Meson-Nucleon Physics and the Structure of the Nucleon, Kyoto, Japan, 25 - 30 Jul 2016, pp.020028

2016-07-27
06:00
 Tests of Chiral perturbation theory with COMPASS / Friedrich, Jan M (CERN) /COMPASS Collaboration The COMPASS experiment at CERN accesses pion-photon reactions via the Primakoff effect., where high-energetic pions react with the quasi-real photon field surrounding the target nuclei. When a single real photon is produced, pion Compton scattering is accessed and from the measured cross-section shape, the pion polarisability is determined. [...] 2014 - 4 p. - Published in : EPJ Web Conf. 73 (2014) 05011 Fulltext: PDF; In : 13th International Conference on Meson-Nucleon Physics and the Structure of the Nucleon, Rome, Italy, 30 Sep - 4 Oct 2013, pp.05011

2016-06-08
06:45
 New results from COMPASS / Kabuß, Eva-Maria (Mainz U.) /COMPASS Collaboration An overview on recent COMPASS results is given, including the extraction of the longitudinal spin structure functions interpreted with a NLO QCD fit, new results on the gluon polarisation and a measurement of pion and kaon multiplicities with a LO extraction of quark-to-hadron fragmentation functions SISSA, 2015 - 6 p. - Published in : PoS: EPS-HEP2015 (2015) , pp. 502 Fulltext: PDF; External link: Published version from PoS In : European Physical Society Conference on High Energy Physics 2015, Vienna, Austria, 22 - 29 Jul 2015, pp.502

2016-06-08
06:45
 Generalized Parton Distributions program at COMPASS / Fuchey, Eric (Saclay) /COMPASS Collaboration SISSA, 2015 - Published in : PoS: QCDEV2015 (2015) , pp. 048 Fulltext: PDF; External link: Published version from PoS In : QCD Evolution Workshop, Newport News, VA, USA, 26-30 May 2015, pp.048

2016-06-08
06:45
 Precision Hadron Spectroscopy at COMPASS - The Scalar Isoscalar Meson Spectrum - / Austregesilo, Alexander (Munich, Tech. U.) /COMPASS Collaboration SISSA, 2015 - Published in : PoS: Bormio2015 (2015) , pp. 022 Fulltext: PDF; External link: Published version from PoS In : 53rd International Winter Meeting on Nuclear Physics, Bormio, Italy, 26 - 30 Jan 2015, pp.022