Skip to main content

M. Finger

Followers

2

Following

1

Co-author

1

Public Views

Uploads

Papers by M. Finger

Measurement of J/ψ at forward and backward rapidity in p+p , p+Al , p+Au , and He3+Au collisions at sNN=200 GeV

Physical Review C, 2020

Charmonium is a valuable probe in heavy-ion collisions to study the properties of the quark gluon... more Charmonium is a valuable probe in heavy-ion collisions to study the properties of the quark gluon plasma, and is also an interesting probe in small collision systems to study cold nuclear matter effects, which are also present in large collision systems. With the recent observations of collective behavior of produced particles in small system collisions, measurements of the modification of charmonium in small systems have become increasingly relevant. We present the results of J/ψ measurements at forward and backward rapidity in various small collision systems, p+p, p+Al, p+Au and 3 He+Au, at √ s N N =200 GeV. The results are presented in the form of the observable RAB, the nuclear modification factor, a measure of the ratio of the J/ψ invariant yield compared to the scaled yield in p+p collisions. We examine the rapidity, transverse momentum, and collision centrality dependence of nuclear effects on J/ψ production with different projectile sizes p and 3 He, and different target sizes Al and Au. The modification is found to be strongly dependent on the target size, but to be very similar for p+Au and 3 He+Au. However, for 0%-20% central collisions at backward rapidity, the modification for 3 He+Au is found to be smaller than that for p+Au, with a mean fit to the ratio of 0.89 ± 0.03(stat)±0.08(syst), possibly indicating final state effects due to the larger projectile size.

J/ψ and ψ(2S) production at forward rapidity in p+p collisions at s=510 GeV

Physical Review D, 2020

Measurements of directed, elliptic, and triangular flow in Cu + Au collisions at sNN=200 GeV

Physical Review C, 2016

ForwardJ/ψproduction in U + U collisions atsNN=193GeV

Physical Review C, 2016

The invariant yields, dN/dy, for J/ψ production at forward rapidity (1.2 < |y| < 2.2) in U+U coll... more The invariant yields, dN/dy, for J/ψ production at forward rapidity (1.2 < |y| < 2.2) in U+U collisions at √ s N N =193 GeV have been measured as a function of collision centrality. The invariant yields and nuclear-modification factor RAA are presented and compared with those from Au+Au collisions in the same rapidity range. Additionally, the direct ratio of the invariant yields from U+U and Au+Au collisions within the same centrality class is presented, and used to investigate the role of cc coalescence. Two different parameterizations of the deformed Woods-Saxon distribution were used in Glauber calculations to determine the values of the number of nucleon-nucleon collisions in each centrality class, N coll , and these were found to give significantly different N coll values. Results using N coll values from both deformed Woods-Saxon distributions are presented. The measured ratios show that the J/ψ suppression, relative to binary collision scaling, is similar in U+U and Au+Au for peripheral and midcentral collisions, but that J/ψ show less suppression for the most central U+U collisions. The results are consistent with a picture in which, for central collisions, increase in the J/ψ yield due to cc coalescence becomes more important than the decrease in yield due to increased energy density. For midcentral collisions, the conclusions about the balance between cc coalescence and suppression depend on which deformed Woods-Saxon distribution is used to determine N coll .

Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons

Nuclear Physics B, 2014

Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produce... more Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS muon beam at 160 GeV/c and a 6 LiD target. The amplitudes of the three azimuthal modulations cos φ h , cos 2φ h and sin φ h were obtained binning the data separately in each of the relevant kinematic variables x, z or p h T and binning in a three-dimensional grid of these three variables. The amplitudes of the cos φ h and cos 2φ h modulations show strong kinematic dependencies both for positive and negative hadrons.

The KASCADE-grande experiment

AIP Conference Proceedings, 2009

Observation of Direct-Photon Collective Flow inAu+AuCollisions atsNN=200 GeV

Physical Review Letters, 2012

First Measurement of Chiral Dynamics inπ−γ→π−π−π+

Physical Review Letters, 2012

The COMPASS Collaboration at CERN has investigated the À ! À À þ reaction at center-ofmomentum en... more The COMPASS Collaboration at CERN has investigated the À ! À À þ reaction at center-ofmomentum energy below five pion masses, ffiffi ffi s p < 5m , embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t 0 < 0:001 GeV 2 =c 2 . Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3-invariant mass m 3 ¼ ffiffi ffi s p were extracted. The absolute cross section was determined in seven bins of ffiffi ffi s p with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.

Search for Three-Jet Resonances inppCollisions ats=7 TeV

Physical Review Letters, 2011

A model-independent search for three-jet hadronic resonance production in pp collisions at a cent... more A model-independent search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 pb -1 . Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed. The number of expected standard model background events is found to be in good agreement with the observed events. Limits are set on a model describing the production of R-parity-violating supersymmetric gluino pairs, and gluino masses in the range of 200 to 280 GeV/c 2 are excluded at a 95% confidence level for the first time.

Leading and next-to-leading order gluon polarization in the nucleon and longitudinal double spin asymmetries from open charm muoproduction

Physical Review D, 2013

The gluon polarization in the nucleon was measured using open charm production by scattering 160 ... more The gluon polarization in the nucleon was measured using open charm production by scattering 160 GeV=c polarized muons off longitudinally polarized protons or deuterons. The data were taken by the COMPASS Collaboration between 2002 and 2007. A detailed account is given of the analysis method that includes the application of neural networks. Several decay channels of D 0 mesons are investigated. Longitudinal spin asymmetries of the D meson production cross sections are extracted in bins of D 0 transverse momentum and energy. At leading order QCD accuracy, the average gluon polarization is determined as hÁg=gi LO ¼ À0:06 AE 0:21ðstat:Þ AE 0:08ðsyst:Þ at the scale h 2 i % 13 ðGeV=cÞ 2 and an average gluon momentum fraction hxi % 0:11. The average gluon polarization is also obtained at next-to-leading order QCD accuracy as hÁg=gi NLO ¼ À0:13 AE 0:15ðstat:Þ AE 0:15ðsyst:Þ at the scale h 2 i % 13 ðGeV=cÞ 2 and hxi % 0:20.

Results from KASCADE–Grande

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012

The KASCADE-Grande experiment, located at Karlsruhe Institute of Technology (Germany) is a multic... more The KASCADE-Grande experiment, located at Karlsruhe Institute of Technology (Germany) is a multicomponent extensive air-shower experiment devoted to the study of cosmic rays and their interactions at primary energies 10 14 -10 18 eV. Main goals of the experiment are the measurement of the all-particle energy spectrum and mass composition in the 10 16 -10 18 eV range by sampling charged (N ch ) and muon (N m ) components of the air shower. The method to derive the energy spectrum and its uncertainties, as well as the implications of the obtained result, is discussed. An overview of the analyses performed by KASCADE-Grande to derive the mass composition of the measured high-energy comic rays is presented as well.

Investigation of the properties of galactic cosmic rays with the KASCADE-Grande experiment

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2011

The properties of galactic cosmic rays are investigated with the KASCADE-Grande experiment in the... more

First performances of COMPASS RICH-1

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

COMPASS RICH-1, designed in 1996 for hadron identification at high momenta in the COMPASS large a... more COMPASS RICH-1, designed in 1996 for hadron identification at high momenta in the COMPASS large angle spectrometer, is based on the use of MWPCs with large size CsI photon detectors. This choice, dictated by technical and economical considerations, has imposed VUV requirements for mirror reflectance and radiator transparency. The detector is now fully operative and its preliminary performances are presented.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2003

RICH-1 is a large acceptance gaseous RICH using 3 m of C 4 F 10 as radiator and MWPCs with CsI ph... more RICH-1 is a large acceptance gaseous RICH using 3 m of C 4 F 10 as radiator and MWPCs with CsI photo-cathodes as VUV photon detectors. The main characteristics of this RICH are the large acceptance and the use of far UV photon detectors, which implies large dimensions, UV transparencies of the elements up to the photo-cathode, and good UV mirror reflectance. We give a description of the detector, first results about its performances and a report about various technological achievements required by this challenging project.

Results from COMPASS RICH-1

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

COMPASS RICH-1, designed in 1996 for hadron identification at high momenta in the COMPASS large a... more COMPASS RICH-1, designed in 1996 for hadron identification at high momenta in the COMPASS large angle spectrometer, is a large acceptance gaseous RICH with a 3m thick C4F10 radiator. MWPCs with CsI photocathodes are used as VUV photon detectors and the image focalization is provided by a large UV mirror wall. π/K are separated in the several 10GeV/c domain.The main

CMS Physics Technical Design Report: Addendum on High Density QCD with Heavy Ions

Journal of Physics G: Nuclear and Particle Physics, 2007

This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics... more This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies √ s N N = 5.5 TeV, will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction -Quantum Chromodynamics (QCD) -in extreme conditions of temperature, density and parton momentum fraction (low-x). This report covers in detail the potential of CMS to carry out a series of representative Pb-Pb measurements. These include "bulk" observables, (charged hadron multiplicity, low p T inclusive hadron identified spectra and elliptic flow) which provide information on the collective properties of the system, as well as perturbative probes such as quarkonia, heavy-quarks, jets and high p T hadrons which yield "tomographic" information of the hottest and densest phases of the reaction.

Nuclear orientation study of the decay of208At (T 1/2=1.63 h) and209At (T 1/2=5.41 h) implanted in iron host

Hyperfine Interactions, 1987

We have measured the angular distribution of gamma-rays in 208,209Po following the decay of the m... more We have measured the angular distribution of gamma-rays in 208,209Po following the decay of the mass-separated isotopes 208,209At polarized at low temperatures in an iron host. Multipole mixing ratios were deduced for 14 and 9 gamma-ray transitions in 208Po and 209Po, respectively, and unambiguous spin-assignments were made for several levels in both nuclei.

Nuclear orientation study of low temperature magnetization of54Mn impurity in ferromagnetic PtFe alloys

Hyperfine Interactions, 1990

Low-temperature nuclear orientation of54Mn in ferromagnetic Pt95Fe5 and Pt90Fe10 hosts has been i... more Low-temperature nuclear orientation of54Mn in ferromagnetic Pt95Fe5 and Pt90Fe10 hosts has been investigated in 12–50 mK temperature range at external magnetic fields up to 1.2 T. Temperature dependence of the effective magnetic field Beff on Mn has been observed and interpreted as an effect of misalignment of Mn magnetic moments with respect to the macroscopic magnetization direction at host magnetic saturation.

Linear polarization and directional distribution of gamma-rays from oriented172Lu

Czechoslovak Journal of Physics, 1983

ConclusionsThe gamma-ray linear polarization data in combination with the results of the directio... more ConclusionsThe gamma-ray linear polarization data in combination with the results of the directional distribution measurements were used to determine precise values of the multipole mixing ratios of the gamma-transitions in the172Yb nucleus. A detailed analysis of the deduced mixing ratios, supplemented by previous data, lends support to the following description of the two-quasiparticle excitations of192Yb (see also tab. 6): 2073 keVKπ = (4+) {p 4041 ↓ + p 411 ↓} + {n 514↓ − n 521↓} 1663 keVKπ = (3+) {n 514↓ − n 521↓} + {n 512↑ − n 521↓} 1172 keVKπ = 3+ {n 512↑ + n 521↓} + {p404↓ − P 411↓} A supporting evidence has also been given to the spin-parity assignments of the 1640 keV (Iπ = 4−) and 1706 keV (Iπ = 5−) members of theKπ = 4− band.

$Research paper thumbnail of Search for the $\phi1860$ Pentaquark at COMPASS$

Search for the $\phi1860$ Pentaquark at COMPASS

The European Physical Journal C, 2005