Report from the MoEDAL Software Group Janusz Chwastowski, Dominik Derendarz, Pawel Malecki, Rafal Staszewski, Maciej Trzebinski (Cracow) Akshay Katre, Philippe Mermod (Geneva) Matthew King, Vasiliki A. Mitsou, Vicente Vento (Valencia) Jim Pinfold, Richard Soluk (Alberta)
2 MoEDAL Meeting V.A. Mitsou MoEDAL Software Group • Coordinator: Philippe Mermod & Jim Pinfold • Groups ▫ Alberta ▫ Cracow ▫ Geneva ▫ Valencia • Meetings: every two weeks; Thursday 16:00 • Mailing list: MoEDAL-Software@cern.ch • Web page: under construction
3 MoEDAL Meeting V.A. Mitsou Action plan 2014 • Material description (short term) ▫ component implementation into the LHCb geometry ▫ gathering info from picture database and CERN Drawing Database (CDD) • Model-independent simulations (short term) ▫ single-particle generator ▫ Geant4 propagation • Model-specific simulations (long term) ▫ Drell-Yan monopole production ▫ other monopole models with different kinematics ▫ Long-lived sparticle (sleptons, R-hadrons) production identify optimum model for MoEDAL reach
4 MoEDAL Meeting V.A. Mitsou LHCb software • LHCb software is organised into: Packages: Sets of classes for a particular purpose (tools, algorithms, etc) Groups: Sets of packages that perform similar operations or work in a particular processing step (Generation, Simulation, etc) Projects: Complete Gaudi software packages consisting of several groups • LHCb contact: Gloria Corti • Relevant for MoEDAL ▫ Panoramix: Interactive Data Visualisation project ▫ Gauss: The LHCb Simulation Program ▫ GiGa (Geant4 in Gauss): interface package between Gauss and Geant4
5 MoEDAL Meeting V.A. Mitsou Material description • MoEDAL placed around the LHCb interaction point on the backward side of the detector • Estimating the amount of material on the back of LHCb provides the trapping potential of MoEDAL
6 MoEDAL Meeting V.A. Mitsou Vacuum vessel I Fluka CDD drawing https://edms.cern.ch/cdd/plsql/c4w.get_in photo
7 MoEDAL Meeting V.A. Mitsou Vacuum vessel II • Combining previous information in Panoramix Project from LHCb existing description after including actual material
8 MoEDAL Meeting V.A. Mitsou Magnetic Monopole Trapper (MMT) • Aluminium absorber • Induction technique for signature of magnetic monopole • 2012 deployment ▫ array placed 1.8 m away from the interaction point, covers 1.3 % of the total solid angle ▫ search for monopoles performed in SQUID magnetometer in ETH Zurich ▫ Bendtz, Katre, Lacarrère, Mermod, Milstead, Pinfold, Soluk “Search in 8 TeV proton-proton collisions with the MoEDAL monopole-trapping test array”, arXiv:1311.6940 [physics.ins-det]
9 MoEDAL Meeting V.A. Mitsou MMT geometry in simulation Rods of aluminium absorber Boxes
10 MoEDAL Meeting V.A. Mitsou MoEDAL simulation • GiGa provides a set of base classes for: Physics lists, Field setups, etc ▫ New physics is implemented in an inheriting class and added to the Gauss algorithm • Monopole physics is added to Gauss by adding G i Ga Ph ysContruc t or M o n op o l e (MonopolePhysics) to the algorithm’s Physics List • Simulation with single monopole production ▫ momentum 1 – 100 GeV ▫ monopole mass set to 100 GeV ▫ magnetic field set off in transportation code ▫ MMT geometry is included – yet not seen → under investigation
11 MoEDAL Meeting V.A. Mitsou Geometry profile • MoEDAL is in negative z y [mm] r [mm] x [mm] z [mm]
12 MoEDAL Meeting V.A. Mitsou 1 GeV Monopole range vs. φ Range [mm] • Flat range in φ save for variations due to known material φ [rad] 10 GeV 100 GeV Range [mm] Range [mm] φ [rad] φ [rad]
13 MoEDAL Meeting V.A. Mitsou 1 GeV Monopole range vs. θ Range [mm] • MoEDAL is in θ > π /2 • Cavern wall at high- θ , high-range region (“curve”) θ [rad] 10 GeV 100 GeV Range [mm] Range [mm] θ [rad] θ [rad]
14 MoEDAL Meeting V.A. Mitsou 1 GeV Monopole range vs. θ and φ Range [mm] φ [rad] • MoEDAL is in θ > π /2 θ [rad] 10 GeV 100 GeV φ [rad] φ [rad] Range [mm] Range [mm] θ [rad] θ [rad]
15 MoEDAL Meeting V.A. Mitsou Simulation ntuple contents • Currently include ▫ initial vertex position ▫ initial momentum ▫ particle PDG code ▫ particle mass ▫ final vertex position • Desired content to be decided
Simulation of monopole production Ι • 1 st monopole revolution: Dirac Theory monopole coupling Dirac quantisation condition : e g = N/2 g 2 ~ 34 i. monopole mass parameter ii. iii. spin unknown iv. Dirac string No well-defined field theory exists Schwinger-Zwanziger not useful for calculations • Naive calculations: Drell-Yan production at LHC included in MADGRAPH e g β Modifications leading to a smaller effective coupling i) Ginzburg et al. loop effects g g E/m ii) Milton et al . for real monopoles beta coupling g g p/E Both effects reduce the coupling close to threshold
17 MoEDAL Meeting V.A. Mitsou Simulation of monopole production ΙΙ • 2 nd monopole revolution: ‘t Hooft-Polyakov soliton i. GUT mass scale ii. the monopole has structure • We would like to go beyond the naive calculations guided by the solitonic picture! • Assumptions i. there is a monopole at the TeV scale ii. it is (solitonic) not elementary iii. its mass is unknown iv. its spin is unknown
18 MoEDAL Meeting V.A. Mitsou Simulation of monopole production ΙΙΙ • Future plan: We are resuscitating old ideas by Schiff and Goebel (before soliton) giving the monopole a structure, larger than its classical radius, with the magnetic charge distributed in it. This structure leads in the calculations to a form-factor which allows reasonable calculations like in the pi-N interaction where the coupling is also large. • Moreover, it allows the description of Monopolium , a monopole- anti-monopole bound state, which might lead to other observable effects in MoEDAL • We are analysing different density distributions and sizes studying model dependence • The approach can also be extended to cosmological scenarios • Caveat: It is important to realise, that once the monopole is formed, the DETECTION in MoEDAL occurs via a classical process, and therefore well determined, by the corresponding Maxwell equations. This implies that once a production rate is calculated (or assumed) the detection rate is easy to calculate depending on the geometry and efficiency of MoEDAL.
19 MoEDAL Meeting V.A. Mitsou ICHEP2014 • Abstract on MoEDAL software results accepted for poster presentation: “ Simulation of the MoEDAL experiment” • Presenter: Matt King (Valencia)
20 MoEDAL Meeting V.A. Mitsou Summary • Experience acquired with LHCb software ▫ framework to which MoEDAL simulation is implemented • MMT material already implemented in MoEDAL geometry description ▫ priority item in view of the MMT results from 2012 deployment • First tests done with single-monopole production and propagation are positive • Different monopole production mechanisms under study
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