diff -u -r1.5 -r1.6
--- HPSEcalCluster.java	8 May 2012 15:49:32 -0000	1.5
+++ HPSEcalCluster.java	4 Jun 2012 23:03:58 -0000	1.6
@@ -11,7 +11,7 @@

  * Cluster with position defined by seed hit (for 1-bit trigger)
  *
  * @author Sho Uemura <[log in to unmask]>

- * @version $Id: HPSEcalCluster.java,v 1.5 2012/05/08 15:49:32 meeg Exp $

+ * @version $Id: HPSEcalCluster.java,v 1.6 2012/06/04 23:03:58 meeg Exp $

  */
 public class HPSEcalCluster extends BasicCluster {
 

@@ -25,7 +25,6 @@

     public HPSEcalCluster(CalorimeterHit seedHit) {
         this.seedHit = seedHit;
         this.cellID = seedHit.getCellID();

-        this.addHit(seedHit);

     }
 
     public CalorimeterHit getSeedHit() {

diff -u -r1.20 -r1.21
--- HPSEcalClusterer.java	4 May 2012 20:29:02 -0000	1.20
+++ HPSEcalClusterer.java	4 Jun 2012 23:03:58 -0000	1.21
@@ -23,11 +23,10 @@

  * @author Jeremy McCormick <[log in to unmask]>
  * @author Tim Nelson <[log in to unmask]>
  *

- * @version $Id: HPSEcalClusterer.java,v 1.20 2012/05/04 20:29:02 meeg Exp $

+ * @version $Id: HPSEcalClusterer.java,v 1.21 2012/06/04 23:03:58 meeg Exp $

  */
 public class HPSEcalClusterer extends Driver {
 

-

     HPSEcal3 ecal;
     String ecalCollectionName;
     String ecalName;

@@ -158,6 +157,7 @@

             if (isSeed) {
                 // Make a cluster from the hit list.
                 HPSEcalCluster cluster = new HPSEcalCluster(hit);

+                cluster.addHit(hit);

                 for (CalorimeterHit clusHit : neighborHits) {
                     cluster.addHit(clusHit);
                 }

diff -u -r1.3 -r1.4
--- HPSEcalCTPClusterer.java	8 May 2012 15:49:32 -0000	1.3
+++ HPSEcalCTPClusterer.java	4 Jun 2012 23:03:58 -0000	1.4
@@ -1,19 +1,23 @@

 package org.lcsim.hps.recon.ecal;
 
 import java.util.ArrayList;

+import java.util.Collection;
+import java.util.Comparator;

 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;

+import java.util.PriorityQueue;

 import java.util.Set;
 
 import org.lcsim.event.CalorimeterHit;

-import org.lcsim.event.Cluster;

+//import org.lcsim.event.Cluster;

 import org.lcsim.event.EventHeader;
 import org.lcsim.geometry.Detector;
 import org.lcsim.geometry.IDDecoder;
 import org.lcsim.geometry.subdetector.HPSEcal3.NeighborMap;
 import org.lcsim.geometry.subdetector.HPSEcal3;

+import org.lcsim.hps.recon.ecal.HPSEcalCTPClusterer.TimeComparator;

 import org.lcsim.util.Driver;
 import org.lcsim.util.lcio.LCIOConstants;
 

@@ -25,220 +29,268 @@

  * @author Jeremy McCormick <[log in to unmask]>
  * @author Tim Nelson <[log in to unmask]>
  * @author Sho Uemura <[log in to unmask]>

- * @version $Id: HPSEcalCTPClusterer.java,v 1.3 2012/05/08 15:49:32 meeg Exp $

+ * @version $Id: HPSEcalCTPClusterer.java,v 1.4 2012/06/04 23:03:58 meeg Exp $

  */
 public class HPSEcalCTPClusterer extends Driver {
 

-	HPSEcal3 ecal;
-	IDDecoder dec;
-	String ecalName;
-	String ecalCollectionName;
-	String clusterCollectionName = "EcalClusters";
-	Set<Long> clusterCenters = null;
-	Map<Long, Double> hitSums = null;
-	Map<Long, CalorimeterHit> hitMap = null;
-	// Map of crystals to their neighbors.
-	NeighborMap neighborMap = null;
-
-	public HPSEcalCTPClusterer() {
-	}
-
-	public void setClusterCollectionName(String clusterCollectionName) {
-		this.clusterCollectionName = clusterCollectionName;
-	}
-
-	public void setEcalCollectionName(String ecalCollectionName) {
-		this.ecalCollectionName = ecalCollectionName;
-	}
-
-	public void setEcalName(String ecalName) {
-		this.ecalName = ecalName;
-	}
-
-	public void startOfData() {
-		if (ecalCollectionName == null) {
-			throw new RuntimeException("The parameter ecalCollectionName was not set!");
-		}
-
-		if (ecalName == null) {
-			throw new RuntimeException("The parameter ecalName was not set!");
-		}
-	}
-
-	public void detectorChanged(Detector detector) {
-		// Get the Subdetector.
-		ecal = (HPSEcal3) detector.getSubdetector(ecalName);
-
-		// Get the decoder for the ECal IDs.
-		dec = ecal.getIDDecoder();
-
-		// Cache ref to neighbor map.
-		neighborMap = ecal.getNeighborMap();
-
-		clusterCenters = new HashSet<Long>();
-		//Make set of valid cluster centers.
-		for (Long cellID : neighborMap.keySet()) {
-			boolean isValidCenter = true;
-			Set<Long> neighbors = neighborMap.get(cellID);
-			for (Long neighborID : neighbors) {
-				Set<Long> neighborneighbors = new HashSet<Long>();
-				neighborneighbors.addAll(neighborMap.get(neighborID));
-				neighborneighbors.add(neighborID);
-
-				if (neighborneighbors.containsAll(neighbors)) {
-					isValidCenter = false;
-					break;
-				}
-			}
-			if (isValidCenter) {
-				clusterCenters.add(cellID);
-			}
-		}
-
-		//System.out.println(ecal.getName());
-		//System.out.println("  nx="+ecal.nx());
-		//System.out.println("  ny="+ecal.ny());
-		//System.out.println("  beamgap="+ecal.beamGap());
-		//System.out.println("  dface="+ecal.distanceToFace());
-
-		//System.out.println(neighborMap.toString());
-	}
-
-	public void process(EventHeader event) {
-		//System.out.println(this.getClass().getCanonicalName() + " - process");
-
-		// Get the list of raw ECal hits.
-		List<CalorimeterHit> hits = event.get(CalorimeterHit.class, ecalCollectionName);
-		if (hits == null) {
-			throw new RuntimeException("Event is missing ECal raw hits collection!");
-		}
-
-		// Get the list of raw ECal hits.
-
-		sumHits(hits);
-
-		// Put Cluster collection into event.
-		int flag = 1 << LCIOConstants.CLBIT_HITS;
-		event.put(clusterCollectionName, createClusters(), HPSEcalCluster.class, flag);
-	}
-
-	public void sumHits(List<CalorimeterHit> hits) {
-		// Hit map.
-		hitMap = new HashMap<Long, CalorimeterHit>();
-
-		hitSums = new HashMap<Long, Double>();
-		// Loop over ECal hits to compute energy sums
-		for (CalorimeterHit hit : hits) {
-			// Make a hit map for quick lookup by ID.
-			hitMap.put(hit.getCellID(), hit);
-
-			// Get neighbor crystal IDs. 
-			Set<Long> neighbors = neighborMap.get(hit.getCellID());
-
-			if (neighbors == null) {
-				throw new RuntimeException("Oops!  Set of neighbors is null!");
-			}
-
-			Double hitSum;
-
-			if (clusterCenters.contains(hit.getCellID())) {
-				hitSum = hitSums.get(hit.getCellID());
-				if (hitSum == null) {
-					hitSums.put(hit.getCellID(), hit.getRawEnergy());
-				} else {
-					hitSums.put(hit.getCellID(), hitSum + hit.getRawEnergy());
-				}
-			}
-
-			// Loop over neighbors to make hit list for cluster.
-			for (Long neighborId : neighbors) {
-				if (!clusterCenters.contains(neighborId)) {
-					continue;
-				}
-				hitSum = hitSums.get(neighborId);
-				if (hitSum == null) {
-					hitSums.put(neighborId, hit.getRawEnergy());
-				} else {
-					hitSums.put(neighborId, hitSum + hit.getRawEnergy());
-				}
-			}
-		}
-	}

+    HPSEcal3 ecal;
+    IDDecoder dec;
+    String ecalName;
+    String ecalCollectionName;
+    String clusterCollectionName = "EcalClusters";
+    Set<Long> clusterCenters = null;
+    Map<Long, Double> hitSums = null;
+    Map<Long, CalorimeterHit> hitMap = null;
+    // Map of crystals to their neighbors.
+    NeighborMap neighborMap = null;
+    double clusterWindow = -1;
+
+    public HPSEcalCTPClusterer() {
+    }
+
+    public void setClusterWindow(double clusterWindow) {
+        this.clusterWindow = clusterWindow;
+    }
+
+    public void setClusterCollectionName(String clusterCollectionName) {
+        this.clusterCollectionName = clusterCollectionName;
+    }
+
+    public void setEcalCollectionName(String ecalCollectionName) {
+        this.ecalCollectionName = ecalCollectionName;
+    }
+
+    public void setEcalName(String ecalName) {
+        this.ecalName = ecalName;
+    }
+
+    public void startOfData() {
+        if (ecalCollectionName == null) {
+            throw new RuntimeException("The parameter ecalCollectionName was not set!");
+        }
+
+        if (ecalName == null) {
+            throw new RuntimeException("The parameter ecalName was not set!");
+        }
+    }
+
+    public void detectorChanged(Detector detector) {
+        // Get the Subdetector.
+        ecal = (HPSEcal3) detector.getSubdetector(ecalName);
+
+        // Get the decoder for the ECal IDs.
+        dec = ecal.getIDDecoder();
+
+        // Cache ref to neighbor map.
+        neighborMap = ecal.getNeighborMap();
+
+        clusterCenters = new HashSet<Long>();
+        //Make set of valid cluster centers.
+        for (Long cellID : neighborMap.keySet()) {
+            boolean isValidCenter = true;
+            Set<Long> neighbors = neighborMap.get(cellID);
+            for (Long neighborID : neighbors) {
+                Set<Long> neighborneighbors = new HashSet<Long>();
+                neighborneighbors.addAll(neighborMap.get(neighborID));
+                neighborneighbors.add(neighborID);
+
+                if (neighborneighbors.containsAll(neighbors)) {
+                    isValidCenter = false;
+                    break;
+                }
+            }
+            if (isValidCenter) {
+                clusterCenters.add(cellID);
+            }
+        }
+
+        //System.out.println(ecal.getName());
+        //System.out.println("  nx="+ecal.nx());
+        //System.out.println("  ny="+ecal.ny());
+        //System.out.println("  beamgap="+ecal.beamGap());
+        //System.out.println("  dface="+ecal.distanceToFace());
+
+        //System.out.println(neighborMap.toString());
+    }
+
+    public void process(EventHeader event) {
+        //System.out.println(this.getClass().getCanonicalName() + " - process");
+
+        // Get the list of raw ECal hits.
+        List<CalorimeterHit> hits = event.get(CalorimeterHit.class, ecalCollectionName);
+        if (hits == null) {
+            throw new RuntimeException("Event is missing ECal raw hits collection!");
+        }
+
+        List<HPSEcalCluster> clusters;
+
+        if (clusterWindow >= 0) {
+            PriorityQueue<CalorimeterHit> futureHits = new PriorityQueue<CalorimeterHit>(10, new TimeComparator());
+            PriorityQueue<CalorimeterHit> pastHits = new PriorityQueue<CalorimeterHit>(10, new TimeComparator());
+            clusters = new ArrayList<HPSEcalCluster>();
+
+            for (CalorimeterHit hit : hits) {
+                futureHits.add(hit);
+            }
+
+            while (!futureHits.isEmpty()) {
+                CalorimeterHit nextHit = futureHits.poll();
+                pastHits.add(nextHit);
+                while (!futureHits.isEmpty() && futureHits.peek().getTime() == nextHit.getTime()) {
+                    pastHits.add(futureHits.poll());
+                }
+                while (pastHits.peek().getTime() < nextHit.getTime() - clusterWindow) {
+                    pastHits.poll();
+                }
+                sumHits(pastHits);
+                clusters.addAll(createClusters());
+            }
+        } else {
+            sumHits(hits);
+            clusters = createClusters();
+        }
+
+        // Put Cluster collection into event.
+        int flag = 1 << LCIOConstants.CLBIT_HITS;
+        event.put(clusterCollectionName, clusters, HPSEcalCluster.class, flag);
+    }
+
+    public void sumHits(Collection<CalorimeterHit> hits) {
+        // Hit map.
+        hitMap = new HashMap<Long, CalorimeterHit>();
+
+        hitSums = new HashMap<Long, Double>();
+        // Loop over ECal hits to compute energy sums
+        for (CalorimeterHit hit : hits) {
+            // Make a hit map for quick lookup by ID.
+            hitMap.put(hit.getCellID(), hit);
+
+            // Get neighbor crystal IDs. 
+            Set<Long> neighbors = neighborMap.get(hit.getCellID());
+
+            if (neighbors == null) {
+                throw new RuntimeException("Oops!  Set of neighbors is null!");
+            }
+
+            Double hitSum;
+
+            if (clusterCenters.contains(hit.getCellID())) {
+                hitSum = hitSums.get(hit.getCellID());
+                if (hitSum == null) {
+                    hitSums.put(hit.getCellID(), hit.getRawEnergy());
+                } else {
+                    hitSums.put(hit.getCellID(), hitSum + hit.getRawEnergy());
+                }
+            }
+
+            // Loop over neighbors to make hit list for cluster.
+            for (Long neighborId : neighbors) {
+                if (!clusterCenters.contains(neighborId)) {
+                    continue;
+                }
+                hitSum = hitSums.get(neighborId);
+                if (hitSum == null) {
+                    hitSums.put(neighborId, hit.getRawEnergy());
+                } else {
+                    hitSums.put(neighborId, hitSum + hit.getRawEnergy());
+                }
+            }
+        }
+    }

-	public List<HPSEcalCluster> createClusters() {

+    public List<HPSEcalCluster> createClusters() {

 //		boolean printClusters;

-		// New Cluster list to be added to event.
-		List<HPSEcalCluster> clusters = new ArrayList<HPSEcalCluster>();
-		//System.out.println("New event");
-		//for each crystal with a nonzero hit count, test for cluster
-		for (Long possibleCluster : hitSums.keySet()) {
-			Double thisSum = hitSums.get(possibleCluster);
-
-			// Get neighbor crystal IDs.
-			Set<Long> neighbors = neighborMap.get(possibleCluster);
-
-			if (neighbors == null) {
-				throw new RuntimeException("Oops!  Set of neighbors is null!");
-			}
-
-			//Apply peak detector scheme.
-			// Set the ID.
-			dec.setID(possibleCluster);
-			int x1 = dec.getValue("ix");
-			int y1 = dec.getValue("iy");

+        // New Cluster list to be added to event.
+        List<HPSEcalCluster> clusters = new ArrayList<HPSEcalCluster>();
+        //System.out.println("New event");
+        //for each crystal with a nonzero hit count, test for cluster
+        for (Long possibleCluster : hitSums.keySet()) {
+            Double thisSum = hitSums.get(possibleCluster);
+
+            // Get neighbor crystal IDs.
+            Set<Long> neighbors = neighborMap.get(possibleCluster);
+
+            if (neighbors == null) {
+                throw new RuntimeException("Oops!  Set of neighbors is null!");
+            }
+
+            //Apply peak detector scheme.
+            // Set the ID.
+            dec.setID(possibleCluster);
+            int x1 = dec.getValue("ix");
+            int y1 = dec.getValue("iy");

 //			System.out.printf("\nThis cluster: E= %f, ID=%d, x=%d, y=%d, neighbors=%d\n", thisSum, possibleCluster, x1, y1, neighbors.size());

-			boolean isCluster = true;
-			for (Long neighborId : neighbors) {
-				// Set the ID.
-				dec.setID(neighborId);
-				int x2 = dec.getValue("ix");
-				int y2 = dec.getValue("iy");
-
-				Double neighborSum = hitSums.get(neighborId);
-				if (neighborSum == null) {
-					continue;
-				}

+            boolean isCluster = true;
+            for (Long neighborId : neighbors) {
+                // Set the ID.
+                dec.setID(neighborId);
+                int x2 = dec.getValue("ix");
+                int y2 = dec.getValue("iy");
+
+                Double neighborSum = hitSums.get(neighborId);
+                if (neighborSum == null) {
+                    continue;
+                }

 
 //				System.out.printf("Neighbor cluster: E= %f, ID=%d, x=%d, y=%d, neighbors=%d\n", neighborSum, neighborId, x2, y2, neighborMap.get(neighborId).size());
 

-				if (neighborSum > thisSum) {

+                if (neighborSum > thisSum) {

 //					System.out.println("Reject cluster: sum cut");

-					isCluster = false;
-					break;
-				} //								else if (false) { //ctp
-				//								else if (neighborSum.equals(thisSum) && neighborId > possibleCluster) { //id
-				//								else if (neighborSum.equals(thisSum) && (x1<x2 || (x1==x2 && Math.abs(y1)>Math.abs(y2)))) { //right_in
-				//								else if (neighborSum.equals(thisSum) && (x1<x2 || (x1==x2 && Math.abs(y1)<Math.abs(y2)))) { //right_out
-				//								else if (neighborSum.equals(thisSum) && (x1>x2 || (x1==x2 && Math.abs(y1)>Math.abs(y2)))) { //left_in
-				else if (neighborSum.equals(thisSum) && (x1 > x2 || (x1 == x2 && Math.abs(y1) < Math.abs(y2)))) { //left_out

+                    isCluster = false;
+                    break;
+                } //								else if (false) { //ctp
+                //								else if (neighborSum.equals(thisSum) && neighborId > possibleCluster) { //id
+                //								else if (neighborSum.equals(thisSum) && (x1<x2 || (x1==x2 && Math.abs(y1)>Math.abs(y2)))) { //right_in
+                //								else if (neighborSum.equals(thisSum) && (x1<x2 || (x1==x2 && Math.abs(y1)<Math.abs(y2)))) { //right_out
+                //								else if (neighborSum.equals(thisSum) && (x1>x2 || (x1==x2 && Math.abs(y1)>Math.abs(y2)))) { //left_in
+                else if (neighborSum.equals(thisSum) && (x1 > x2 || (x1 == x2 && Math.abs(y1) < Math.abs(y2)))) { //left_out

 //								else if (neighborSum.equals(thisSum) && (x1<x2 || (x1==x2 && y1<y2))) { //right_up
 //								else if (neighborSum.equals(thisSum) && (x1>x2 || (x1==x2 && y1<y2))) { //left_up
 //					System.out.println("Reject cluster: tie-breaker cut");

-					isCluster = false;
-					break;
-				}
-			}
-
-			if (isCluster) {
-//				System.out.println("Accept this cluster");
-				HPSEcalCluster cluster = new HPSEcalCluster(possibleCluster);
-				CalorimeterHit hit = hitMap.get(possibleCluster);
-				if (hit != null /*&& hit.getRawEnergy() > hitEMin && hit.getRawEnergy() < hitEMax*/) {
-//					System.out.printf("Adding hit, E = %f\n", hit.getRawEnergy());
-					cluster.addHit(hit);
-				}
-
-				for (Long neighborId : neighbors) {
-					// Find the neighbor hit in the event if it exists.
-					hit = hitMap.get(neighborId);
-					if (hit != null /*&& hit.getRawEnergy() > hitEMin && hit.getRawEnergy() < hitEMax*/) {
-//						System.out.printf("Adding hit, E = %f\n", hit.getRawEnergy());
-						cluster.addHit(hit);
-					}
-				}
-				clusters.add(cluster);
-			}
-		}
-		return clusters;
-	}

+                    isCluster = false;
+                    break;
+                }
+            }
+
+            if (isCluster) {
+                List<CalorimeterHit> hits = new ArrayList<CalorimeterHit>();
+                double clusterTime = Double.NEGATIVE_INFINITY;
+                CalorimeterHit hit = hitMap.get(possibleCluster);
+                if (hit != null) {
+                    hits.add(hit);
+                    if (hit.getTime() > clusterTime) {
+                        clusterTime = hit.getTime();
+                    }
+                }
+                for (Long neighborId : neighbors) {
+                    hit = hitMap.get(neighborId);
+                    if (hit != null) {
+                        hits.add(hit);
+                        if (hit.getTime() > clusterTime) {
+                            clusterTime = hit.getTime();
+                        }
+                    }
+                }
+                CalorimeterHit seedHit = new HPSRawCalorimeterHit(0.0, null, clusterTime, possibleCluster, hits.get(0).getType());
+                seedHit.setMetaData(hits.get(0).getMetaData());
+                HPSEcalCluster cluster = new HPSEcalCluster(seedHit);
+                for (CalorimeterHit clusterHit : hits) {
+                    cluster.addHit(clusterHit);
+                }
+                clusters.add(cluster);
+            }
+        }
+        return clusters;
+    }
+
+    static class TimeComparator implements Comparator<CalorimeterHit> {
+
+        public int compare(CalorimeterHit o1, CalorimeterHit o2) {
+            if (o1.getTime() == o2.getTime()) {
+                return 0;
+            } else {
+                return (o1.getTime() > o2.getTime()) ? 1 : -1;
+            }
+        }
+    }

 }