#include <CSCStripHitSim.h>

Public Member Functions
std::vector< CSCDetectorHit > &	simulate (const CSCLayer *layer, const std::vector< CSCDetectorHit > &wireHits)

Private Attributes
std::vector< CSCDetectorHit >	newStripHits

CSCGattiFunction	theGattiFunction

Detailed Description

Class which builds simulated strip hits from wire hits during digitization of Endcap Muon CSCs.

Author: Rick Wilkinson

Definition at line 21 of file CSCStripHitSim.h.

Member Function Documentation

◆ simulate()

std::vector< CSCDetectorHit > & CSCStripHitSim::simulate	(	const CSCLayer *	layer,
		const std::vector< CSCDetectorHit > &	wireHits
	)

Definition at line 10 of file CSCStripHitSim.cc.

References CSCGattiFunction::binValue(), funct::cos(), relativeConstraints::geom, CSCGattiFunction::initChamberSpecs(), nano_mu_digi_cff::layer, SiStripPI::max, SiStripPI::min, newStripHits, CSCChamberSpecs::nNodes(), hltrates_dqm_sourceclient-live_cfg::offset, position, funct::sin(), theGattiFunction, and nano_mu_digi_cff::wire.

Referenced by CSCDigitizer::doAction().

                                                                                                  {
   // make sure the gatti function is initialized
   const CSCChamberSpecs *chamberSpecs = layer->chamber()->specs();
   const CSCLayerGeometry *geom = layer->geometry();
   theGattiFunction.initChamberSpecs(*chamberSpecs);
   const int nNodes = chamberSpecs->nNodes();
 
   // for every wire hit, induce a Gatti-distributed charge on the
   // cathode strips
   newStripHits.clear();
   newStripHits.reserve((2 * nNodes + 1) * wireHits.size());
   std::vector<CSCDetectorHit>::const_iterator wireHitI;
   for (wireHitI = wireHits.begin(); wireHitI != wireHits.end(); ++wireHitI) {
     int wire = (*wireHitI).getElement();
     float wireCharge = (*wireHitI).getCharge();
     float wireHitTime = (*wireHitI).getTime();
     // The wire hit position is _along the wire_, measured from where
     // the wire intersects local y axis, so convert to local x...
     float hitX = (*wireHitI).getPosition() * cos(geom->wireAngle());
     float hitY = geom->yOfWire(wire, hitX);
     const LocalPoint wireHitPos(hitX, hitY);
 
     int centerStrip = geom->nearestStrip(wireHitPos);
     int firstStrip = std::max(centerStrip - nNodes, 1);
     int lastStrip = std::min(centerStrip + nNodes, geom->numberOfStrips());
     for (int istrip = firstStrip; istrip <= lastStrip; istrip++) {
       float offset = hitX - geom->xOfStrip(istrip, hitY);
       float stripWidth = geom->stripPitch(wireHitPos);
       float binValue = theGattiFunction.binValue(offset, stripWidth);
       // we divide by 2 because charge goes on either cathode.
       // if you're following the TDR, we already multiplied the
       // charge by 0.82 in the WireHitSim (well, DriftSim), so that explains
       // their f_ind=0.41.
 
       // this seems to be folded in the Amp response, which peaks
       // around 0.14.  The difference may be because the amp response
       // convolutes in different drift times.
       // float collectionFraction = 0.19;
       const float igain = 1. / 0.9;  // mv/fC
       float stripCharge = wireCharge * binValue * igain * 0.5;
       float stripTime = wireHitTime;
       float position = hitY / sin(geom->stripAngle(istrip));
       CSCDetectorHit newStripHit(istrip, stripCharge, position, stripTime, (*wireHitI).getSimHit());
       newStripHits.push_back(newStripHit);
     }
   }  // loop over wire hits
   return newStripHits;
 }

Member Data Documentation

◆ newStripHits

std::vector<CSCDetectorHit> CSCStripHitSim::newStripHits

private

Definition at line 28 of file CSCStripHitSim.h.

Referenced by simulate().

◆ theGattiFunction

CSCGattiFunction CSCStripHitSim::theGattiFunction