====================================================================== A.Zhokin last update: april.2001 ====================================================================== New FNC-2000 in H1SIM --------------------- 1. Introduction 1a. Simulation 1b. Implementation of new FNC into H1SIM 2. Geometry description of FNC 2a. Detailed geometry 2b. Medium/coarse geometry 3. Mapping 4. Continuous numbering 5. Tracking through FNC 5a. Steering 5b. Detailed tracking 5c The FAST tracking 6. Digitization of F N C 7. Summary ====================================================================== ====================================================================== 1. Introduction To remind: First FNC("spacal") installed in 1996 Aim: provide the calorimetry of neutrons in very forward region for En = 100 - 900 GeV In 1998 - upgrade by a preshower to improve energy, space resolution and e/pi separation Several years of working --> significant deterioration of main FNC characteristics Upgrade of 2001 - new FNC("sandwich") fiducial volume: length - 200 cm transversal size - 60 cm2 ====================================================================== 1a. Simulation: Up to now - the simulation of new FNC was provided by program written by Rim Kutuev - in framework of H1SIM the FNC is presented as a piece of dead material only ====================================================================== 1b. Implementation of new FNC into H1SIM - to provide easy access for everybody in H1 to simulation of FNC response - in any sort of event, - versus response of any H1 detector - expecting reasonable cpu time with H1FAST and new "fast" PCs ====================================================================== ====================================================================== 2. Geometry description of FNC Implementation of volumes with FNC can be seen from sketch below, where the hierarchy of volume levels is shown. JFN0 - the main volume, where the other FNC volumes are located, belong to FBL3 from 92 up to 110 m in Z. l e v 1 2 3 4 5 6 7 8 9 10 e l | | | | | | | | | | | | | | | | | | | | V V V V V V V V V V H1EX LUMI IRON FWFE FBL3 JDX0 .... JFN1 JFN0 FNM1 FDA1 FNA1 FNM2 FDA2 FNA2 FNN2 FDB2 FNB2 for preshower: FNM3 FNO3 FNR3 FNB3 FNP3 FNA3 The JFN0 mother volume can be easily shifted w.r.t. H1 coordinate system. Detailed description of all FNC sizes can be found in FNC manual located in h1sim.cmz (The FNC itself include 8(=2x4) FNM1, 12(3x4) FNM2 and 12(3x4) FNN2 volumes, preshower - FNM3 volume. FDA..,FDB.. volumes are the steel skin of the modules, FNA1, FNA2, FNB2, FNA3, FNB3 volumes include sensitive volumes of the FNC and preshower.) ====================================================================== 2a. Detailed geometry (scintillator+lead)/ granularity = 1 : ............................................... The volumes FNA1,FNA2/FNB2 and FNA3/FNB3 in detailed description have in addition the next hierarchy: l e v 1 2 3 4 5 6 7 8 9 10 e l | | | | | | | | | | | | | | | | | | | | V V V V V V V V V V FNA1 FNS4 FNT4 FNE4 FNP4 FNA2 FNS5 FNT5 FNE5 FNP5 FNB2 FNS6 FNT6 FNE6 FNP6 for preshower: FNB3 FNS8 FNT8 FNE8 FNP8 FNA3 FNS7 FNT7 FNE7 FNP7 The volumes FNS... - scintillator, FNT... - tyvec, FNE... - st.steel, FNP... - lead. The volumes FNA2 and FNB2 are filled by the same materials with the same sizes, but location of them for each layers is different. The volumes FNA3 and FNB3 are related to elm. and hadronic part of the preshower. ====================================================================== 2b. Medium/coarse geometry / granularity = 2: ................................. The filling of volumes FNA1,FNA2/FNB2 and FNA3 in that case do not have division on layers inside ones. This volumes - just boxes filled with mixture of lead,scintillator,air,tyvec and st.steel. Mixtures: media number 1239 = Average FNC module(volumes FNA1,FNA2,FNB2) media number 1245 = Average elm.compartment of preshower(volume FNA3) media number 1246 = Average had.compartment of preshower(volume FNB3) ====================================================================== ====================================================================== 3. Mapping ------- (software numbering) ............................ The software numbers M,N,L,I,J,K which GENMAP via call of AUFNCA routine returns for point in space have the following meaning: ====================================================================== M = 14 - FNC and preshower ====================================================================== N = -1 - dead material in front of FNC (L=0,I=0,J=0,K=0) ====================================================================== = 0 - em/had PRESHOWER cell(lead/fibers)(L=0-1,I,J=0-9,K=0) dead in cracks (L=0-1,I,J=0-9,K=-1) ============================================== Preshower strips: J ^ Y^ I I I I I I I-----------------------------------I 9 I I I I I I I I I I I-----------------------------------I 8 I I I I I I I I I I I-----------------------------------I 7 I I I I I I I I I I I-----------------------------------I 6 I I I I I I I I I I I-----------------------------------I 5 I I I I I x I I I I I---------->X I-----------------------------------I 4 I I I I I I I I I I I-----------------------------------I 3 I I I I I I I I I I I-----------------------------------I 2 I I I I I I I I I I I-----------------------------------I 1 I I I I I I I I I I I-----------------------------------I----------------->I 1 2 3 4 5 6 7 8 9 X,Y strips combined in Z: I elm. compartment I had. compartment I I I I I.26cm 1.16cm I 2.01cm I I I I I1 + 12*ZSTPRELM I 12*ZSTPRHAD I I I I Ix y x y x y x y x y x y xIy x y x y x y x y x y xI I I I ====================================================================== N = 1 - FNC Z - sections cells (lead/fibers) (L=0-3; I,J=0-2; K= 0) dead in cracks (L=0-3; I,J=0-2; K= -1) ============================================== in Z -----------------------------> Z Preshower F N C 0 1 0 1 2 3 <------ L I--I---I-I----I----I----I----I Ie Ih IgI m I m I m I m I Il Ia IaI o I o I o I o I Im Id IpI d0 I d1 I d2 I d3 I I--I---I-I----I----I----I----I FNC towers: ============================================== in XY: /-\ Z J ^ ^ I.I I YI \-/ I I I-----------------------I I 1 I I 2 I 2 I I x I I--------->X I-----------------------I I 3 I 4 I 5 I 1 I I I I I-----------------------I I 6 I 7 I 8 I 0 I I I I I---------------------------------> 0 1 2 I ====================================================================== = 2 - dead material in barrel (L=0,I=0,J=0,K=0-2 up/down/left-right) ====================================================================== = 3 - dead material beside the calorimeter (L=0,I=0,J=0,K=0) ====================================================================== ====================================================================== 4. Continuous numbering .................... Continuous number (IS) correspond to readout channel of the FNC tower or X,Y strip of preshower and is stored in bank FNCT. Transformation software numbers <--> continuous number: for signal IS = NFNCCONT(N,L,I,J) CALL NFSOFT(IS,N,L,I,J,IFL) Continuous numbering for FNC + Preshower has no gaps: FNC-1st section, 8 towers - IS = 1 - 8 FNC-2nd section, 8 towers - IS = 9 - 16 FNC-3rd section, 8 towers - IS = 17 - 24 FNC-4th section, 8 towers - IS = 25 - 32 Preshower, 9 X strips - IS = 33 - 41 Preshower, 9 Y strips - IS = 42 - 50 channel does not exist - IS = -1 The inverse mapping function ............................. returns x,y,z of the cell center: CALL FMAPI(N,I,J,XYZ) or CALL FNCMAPI(IS,XYZ,IFL) ====================================================================== ====================================================================== 5. Tracking through FNC -------------------- 5a. Steering: For upgrade simulation one should modify some steering banks. Reasonable choices of simulation are steered by 1) OTTO bank: 0 ! =0 means user settings of parameters (OSGO,OSGD and GFCP) 1 ! =1 means GHEISHA or CALOR (depending on the program name) 2) OSGO bank: 10 ! Configuration setup 1 3) OSGD bank: one can do the choice in column 'FWFE': Granularity 1 - fine 2 - medium 3 - coarse (= medium ) Tracking mode 1 - detailed tracking 3 - fast mode (h1fast) For inline event generation the bank 'EVSI' is used to produce Runs with single track events. In this bank one can assign the coordinates of starting point: in front of preshower, in center of preshower : Xv Yv Zv -1.58 -2.6865 +10592.5 between preshower and FNC, in center of tower 4: Xv Yv Zv -1.58 2.3135 +10633.5 ====================================================================== 5b. Detailed tracking .................. Special choice of cuts and physics processes for FNC+Preshower in detailed tracking is provided by text bank FGTP: 'CUTGAM ' 1.E-5 'CUTELE ' 1.E-5 'CUTNEU ' 1.E-5 'CUTHAD ' 1.E-5 'CUTMUO ' 1.E-5 'BCUTE ' 1.E-5 'BCUTM ' 1.E-5 'DCUTE ' 1.E-5 'DCUTM ' 1.E-5 'DRAY ' 1. 'LOSS ' 3. 'HADR ' 3. 'MULS ' 1. 'PFIS ' 1. 'RAYL ' 1. 'ANNI ' 1. 'BREM ' 1. 'COMP ' 1. 'MUNU ' 1. 'PAIR ' 1. 'PHOT ' 1. ====================================================================== 5c The FAST tracking ................. The fast tracking mode implies the parametrization of shower evolution of electromagnetic particles and the complex simulation for hadrons. The shower evolution of electromagnetic particles is fully parametrized if shower is contained in the homogeneous medium. If shower extend over the dead material(cracks) inside the calorimeter, the detailed simulation is kept. For hadrons, the situation is more complex since a lot of processes are involved and in this case the hadrons are tracked by the GEANT program through the calorimeters. Inelastic interactions and their products are determined at each step of the hadronic shower evolution via the GHEISHA interface. Neutral pions decay into two gammas and their energy deposition is parametrized in the same way as for electromagnetic showers. Paratemers needed for fast simulation are given in GFC0 bank. The name GFC0(since upgrade 2001) is new name instead GFC5. Columns 'FNCA','FNPR' foreseen for FNC and Preshower correspondingly. The parameters in column FNCA related to media number 1239, but in column FNPR - to media numbers 1245 and 1246 simultaneously. ====================================================================== ====================================================================== 6. Digitization of F N C ---------------------- All energy depositions for one particle in the tower or preshower strip are summed. Output FNC digi banks: FRCE,FRCX ! BANKname BANKtype !Comments ! TABLE FRCE B16 ! FNC_Response_Calo_Event bank ! (digitization) ! ATTributes: ! ----------- !COL ATT-name FMT Min Max !Comments ! 1 NCHAN I 1 50 ! channel geometric number : ! 1 - 32: PM signals of FNC tower ! 33 - 41: PM signals of X-presh.strips ! 42 - 50: PM signals of Y-presh.strips 2 ESTACK I 0 65535 ! response of stack - visible weighted ! energy (MeV) END TABLE ====================================================================== ====================================================================== 7. Summary FNC is successfully implemented in H1SIM: detailed and medium granularity detailed and fast tracking digitization first results for fast and detailed simulation are obtained cpu time for 900 GeV pi (with PC 600 MHz, medium granularity and fast tracking) < 5" - 1 event 1h ~ 800 --"-- 1d ~ 20.000 --"-- 1w > 100.000 --"-- ======================================================================