1 / 8

Outline:

Reaction-plane reconstruction and centrality determination at SIS100. V. Pozdnyakov, Yu. Vertogradova (JINR). Outline:. RP for azimuthal correlation studies “seen” effect, requirements in order to “see” input for study results conclusions. z. Reaction

jolene-joseph
Download Presentation

Outline:

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Reaction-plane reconstruction and centrality determination at SIS100 V. Pozdnyakov, Yu. Vertogradova (JINR) Outline: RP for azimuthal correlation studies “seen” effect, requirements in order to “see” input for study results conclusions

  2. z Reaction plane y x remarks on AC Asymmetry of an mid-central ion collision converts to spatial anisotropy of produced hadrons dN/d(f-fRP) ~ S vn cos [ n (f – fRP) ] v1=<cos[f – fRP]> directed flowv2=<cos[2(f – fRP) ]> elliptic flow - defines R, (direction of the impact parameter) Measurement has to go via: a) selection of events within some centrality (correlated to impact parameter) ; b) Reaction Plane (RP) determination measured with p or protons reaction plane via measurement vn,meas = vn <cos[n(fEP – fRP)]> event plane from MC ‘target’ event plane resolution

  3. “seen” effect, requirements to exp v1 and v2 for 6 GeV/n of Au for pions and protons requirements to experiment are to detect remnant neutrons and protons carrying out an info on both centrality of interaction and RP as well pions protons

  4. Input for study 5 kEvents of AuAu at 6 GeV/n with UrQMD and APR08 release Two samples with reaction planefixed at 0 deg (i.e. in x-z plane) and reaction planerandomly rotated around z PSD is simulated as a piece of the plane at a distance from IP and particles hited the plane are considered as detectable PSD is located at distances of 8 and 15 meters from IP Magnetic field is scaled as 0, 0.1, 0.3 or 1(nominal)

  5. reaction plane determination with PSD red – neutrons, green – protons, bars – both combined 08Field0.0 08Field1.0 zero plane randomly orientated plane RP08Field0.0 RP08Field0.1 RP08Field0.3 RP08Field1.0

  6. reaction plane determination with PSD zero plane 15Field0.0 15Field0.1 15Field0.3 randomly orientated plane RP15Field0.1 RP15Field0.3 RP15Field0.0

  7. results prot8m neu15m prot15m beam15m cm Spread between spectator protons and neutrons at 6 GeV/n beam with 1 Tm of bending power is too wide for single PSD at 15 meters Protons, needed to improve centrality measurement, destroy RP reconstruction. and

  8. results Few numbers/points to a proposal drawn below: - RP resolutions are ~40 deg n(p) and ~30 deg with n+p at 8 m - RP resolutions are ~60 deg n(p) and ~40 deg with n+p at 15 m (less participants) - only upstream PSD left-side is to be used for RP reconstruction, i.e. number of spectators are ~twice smaller AND - for that part should be finer granulation for position/angle accuracy- right-side collects mainly protons MF=0 (0.,0.,X) ZDC P(roton)SD BP - granularity of left-side should care of module transverse-energy 'weight' vs radius - such splitting should provide a freedom to detect spectators at different SIS energies - use protons detected in STS/TOF to improve RP resolution

More Related