# COMPASS Conference Proceedings

2019-11-19
06:00
 The online monitoring API for the DIALOG library of the COMPASS experiment / Šubrt, Ondřej (CERN ; CTU, Prague) ; Bodlák, Martin (Charles U., Prague (main)) ; Frolov, Vladimir (Dubna, JINR) ; Huber, Stefan (Tech. U., Munich (main)) ; Jandek, Matouš (CTU, Prague) ; Jarý, Vladimίr (CTU, Prague) ; Květoň, Antonίn (CTU, Prague) ; Levit, Dmytro (Tech. U., Munich (main)) ; Nový, Josef (CTU, Prague) ; Steffen, Dominik (Tech. U., Munich (main)) et al. Modern experiments demand a powerful and efficient Data Acquisition System (DAQ). The intelligent, FPGA-based Data Acquisition System (iF-DAQ) of the COMPASS experiment at CERN is composed of many processes communicating between each other. [...] 2019 - 8 p. - Published in : EPJ Web Conf. 214 (2019) 01020 Fulltext from publisher: PDF; In : 23rd International Conference on Computing in High Energy and Nuclear Physics, CHEP 2018, Sofia, Bulgaria, 9 - 13 Jul 2018, pp.01020

2019-01-18
08:13
 Measurement of azimuthal asymmetries in SIDIS on unpolarized protons / Moretti, Andrea (INFN, Trieste ; Trieste U.) /COMPASS Collaboration The COMPASS Collaboration is measuring the asymmetries in the azimuthal distributions of positive and negative hadrons produced in Deep Inelastic Scattering (DIS) on unpolarized protons. The data have been collected in 2016 and 2017 with a 160 GeV/$c$ muon beam scattering off a liquid hydrogen target. [...] arXiv:1901.01773.- SISSA, 2019-07-31 - 7 p. - Published in : PoS SPIN2018 (2019) 052 Fulltext: 1901.01773 - PDF; PoS(SPIN2018)052 - PDF; In : 23rd International Spin Symposium, Ferrara, Italy, 10 - 14 Sep 2018, pp.052

2017-12-08
07:26
 Muoproduction of exotic charmonia at COMPASS / Guskov, A. (Dubna, JINR) /COMPASS Collaboration Exotic charmonium-like states have been targeted by various experiments in the last 15 years, but their nature still is unknown. Photo-(muo)production is a new promising instrument to study them. [...] arXiv:1712.01345.- SISSA, 2017-11-27 - 5 p. - Published in : PoS Hadron2017 (2018) 125 Fulltext: PDF; Preprint: PDF; External link: PoS server In : XVII International Conference on Hadron Spectroscopy and Structure, Salamanca, Spain, 25 - 29 Sep 2017, pp.125

2017-12-08
07:26
 First results from an extended freed-isobar analysis at COMPASS / Krinner, Fabian Michael (Munich, Tech. U.) /COMPASS Collaboration One of the goals of the COMPASS experiment is the precision study of light-meson spectroscopy with data for various final states. With $46\times10^6$ exclusive events, the process $\pi^- p\to\pi^-\pi^+\pi^- p$ constitutes the flagship channel. [...] arXiv:1711.10828.- SISSA, 2017-11-30 - 6 p. - Published in : PoS Hadron2017 (2018) 034 Fulltext: PoS(Hadron2017)034 - PDF; 1711.10828 - PDF; Preprint: PDF; External link: PoS server In : XVII International Conference on Hadron Spectroscopy and Structure, Salamanca, Spain, 25 - 29 Sep 2017, pp.034

2017-12-01
07:57
 Recent Results on Light-Meson Spectroscopy from COMPASS / Wallner, Stefan (Munich, Tech. U.) /COMPASS Collaboration The main goal of the spectroscopy program at COMPASS is to explore the light-meson spectrum below about $2\,\text{GeV}/c^2$ in diffractive production. Our flagship channel is the decay into three charged pions: $p + \pi^-\to \pi^-\pi^-\pi^+ + p_\text{recoil}$, for which COMPASS has acquired the so far world's largest dataset of roughly $50\,\text{M}$ exclusive events using an $190\,\text{GeV}/c$ $\pi^-$ beam. [...] arXiv:1711.09782.- SISSA, 2017-11-27 - 7 p. - Published in : PoS Hadron2017 (2018) 032 Fulltext: PDF; Preprint: PDF; External link: PoS server In : XVII International Conference on Hadron Spectroscopy and Structure, Salamanca, Spain, 25 - 29 Sep 2017, pp.032

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. - 2017. - 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. - 2017. - 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.- 2017 - 9 p. - Published in : JPS Conf. Proc. 13 (2017) 010018 Preprint: PDF; External link: Fulltext 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;