Recent DHCAL Developments

This talk reports on recent progress concerning the development of a Digital Hadron Calorimeter with Resistive Plate Chambers as active elements. After the successful testing of a Digital Hadron Calorimeter prototype, the DHCAL, in the Fermilab and CERN test beams, the DHCAL group is now tackling some of the remaining technical issues which were not addressed specifically with the prototype. The talk reports on developments related to the RPC chamber design, to improvements in the RPC rate capabilities, the high voltage distribution system, and a gas recirculation system.Comment: Talk presented at the International Workshop on Future Linear Colliders (LCWS13) Tokyo, Japan, 11-15 November 201

Construction of a Digital Hadron Calorimeter

The DHCAL collaboration is assembling a large scale prototype Digital Hadron Calorimeter (DHCAL). The calorimeter utilizes Resistive Plate Chambers (RPCs) as active medium and features of the order of 400,000 1 \times 1 cm2 pads with binary (or digital) electronic readout. The purpose of the prototype is to provide detailed measurements of hadronic showers and to prove the concept of a DHCAL with RPCs as active elements

Hadronic showers in the CALICE calorimeter prototypes

The CALICE collaboration has constructed highly granular electromagnetic and hadronic calorimeter prototypes to evaluate technologies for the use in detector systems at the future International Linear Collider. These calorimeters have been tested extensively in particle beams at CERN and at Fermilab. We present preliminary results of an analysis of hadronic events in the combined system under test at CERN in 2006 and 2007, comprising a SiW ECAL, a scintillator tile HCAL and a scintillator strip tail catcher, the latter two with SiPM readout. The properties of hadronic showers in the HCAL, compared to simulations performed with GEANT4, are discussed. Particular emphasis is placed on the study of the linearity of the detector response and on the single particle energy resolution achievable with simple weighting algorithms based on the local energy density in the hadronic showers.Comment: 3 pages, 4 figures, to appear in the proceedings of TIPP09, Tsukuba, Japan, March 200

Multi-hadron Final States

This summary aims to highlight major results and insights gained from recent studies of hadronic final states in ep, ppbar, e+e-, as well as relevant theoretical developments, presented in the Multi-hadron final states parallel sessions of the DIS2002 workshop held in Krakow, Poland in May 2002.Comment: Contributed to the X International Workshop on Deep Inelastic Scattering (DIS2002), Krakow, Poland, 30 April - 4 May, 200

Analysis of Muon Events in the DHCAL

The Digital Hadron Calorimeter (DHCAL) is a large prototype of an imaging calorimeter using Resistive Plate Chambers (RPCs) as active media. The readout is segmented into 1\times1 cm2 pads, each with a single bit resolution, hence the denomination of digital. The total channel count is close to 500,000. The DHCAL construction and assembly was completed in fall 2010, followed by a series of test beam campaigns in the FTBF test beam at Fermilab. In this paper we report on the analysis of events collected with the broadband muon beam. These events are utilized to geometrically align the layers horizontally and vertically, to establish the response as function of position on a single readout pad, and to measure the performance characteristics of the RPCs, i.e. the efficiency and average pad multiplicity. The latter were measured in both 'clean' regions of the detector, i.e. away from structures such as the rims of the chambers, and as function of position on the entire vertical plane. In addition, the paper reviews the preliminary measurements of the noise rate in the detector

Experimental Tests of Particle Flow Calorimetry

Precision physics at future colliders requires highly granular calorimeters to support the Particle Flow Approach for event reconstruction. This article presents a review of about 10 - 15 years of R\&D, mainly conducted within the CALICE collaboration, for this novel type of detector. The performance of large scale prototypes in beam tests validate the technical concept of particle flow calorimeters. The comparison of test beam data with simulation, of e.g.\ hadronic showers, supports full detector studies and gives deeper insight into the structure of hadronic cascades than was possible previously.Comment: 55 pages, 83 figures, to appear in Reviews of Modern physic

Overview of the DHCAL Project

We review the status and plans of the Digital Hadron Calorimeter with Resistive Plate Chambers project

Resistive Plate Chambers for Imaging Calorimetry - the DHCAL

The DHCAL, the Digital Hadron Calorimeter, is a prototype calorimeter based on Resistive Plate Chambers (RPCs). The design emphasizes the imaging capabilities of the detector in an effort to optimize the calorimeter for the application of Particle Flow Algorithms (PFAs) to the reconstruction of hadronic jet energies in a colliding beam environment. The readout of the chambers is segmented into 1 x 1 cm2 pads, each read out with a 1-bit (single threshold) resolution. The prototype with approximately 500,000 readout channels underwent extensive testing in both the Fermilab and CERN test beams. This talk presents preliminary findings from the analysis of data collected at the test beams

Demining in Urban Centers is a Race Against Time

Identifying and clearing explosive ordnances in formerly embattled areas in Iraq is a matter of priority as refugees and internally displaced persons are returning to their homes. It is a race against time