Semi-Digital Hadronic Calorimeter


One of the innovative concept to be fully tested by the CALICE collaboration is the one of a semi-digital hadronic calorimetry where the deposits from the hadronic showers are recorded with a fine (1×1 cm² cells, 40-50 layers) granularity with only a coarse energy information (2 - 3 thresholds). Based on gaseous sensor (GRPC or MICROMEGAS chambers) the proposed detector also includes, for the first time memory capable and power pulsed embedded readout chips.

This page present the effort of the groups toward the construction and beam test of a full 1 m³ prototype, including most of the dependancies implied by the running at the ILC, totalling 400000 channels.



One possibility for a gaseous HCAL active medium is the Micro Mesh gaseous structure (MICROMEGAS), a detector based on the micro-pattern detector technology, today widely used by many experiments: COMPASS, CAST, NA48, n-TOF, T2K and the ILC TPC project. First prototypes consist of a commercially available fine mesh which separates the drift gap (3 mm) from the amplification gap (128 μm). This simple structure allows full efficiency for MIPs and thanks to thin pillars, provides a good uniformity over the whole surface. The rate obtained with Micromegas chamber is not constrained, as it is the case for the Glass RPC. Moreover the tiny size of the amplification avalanche, results in fast signals without physical cross talk and leads to low multiplicities. The chosen bulk technology based on industrial PCB processes, offers a robust detector with no working voltages higher than 500 V. MICROMEGAS are therefore a very appealing possibility to equip a DHCAL optimized for the PFA.



Very Front-end Electronics

The readout will be done with embedded HARDROC or DIRAC able to store the hits above 3 thresholds for 64 channels with very low consumption (using power pulsing techniques)

Digital Interface Electronics

  • DIF: Digital InterFace board
  • DCC: Digital Concentrated Card
  • LDA: Link-Data aggregator

Data Acquisition

  • ODR: Off-Detector Receiver

The presentation of the SdHCal can be found here;

Presentation in conference.

ILC dependancies

  • low consumption
  • Zero suppression
  • Differed readout
  • Excellent geometric resolution, suitable for the PFA techniques adopted by the ILD and SiD concepts.

Implied Groups

GroupSorted ascending People
CIEMAT - Madrid  
IHEP - Protvino  
IPNL - Lyon  
LAL - Orsay  
LAPP - Annecy Catherine Adloff
LAPP - Annecy Jan Blaha
LAPP - Annecy Sébastien Cap
LAPP - Annecy Maximilien Chefdeville
LAPP - Annecy Alexandre Dalmaz
LAPP - Annecy Cyril Drancourt
LAPP - Annecy Ambroise Espagilière
LAPP - Annecy Raphael Gallet
LAPP - Annecy Nicolas Geffroy
LAPP - Annecy Claude Girard
LAPP - Annecy Richard Hermel
LAPP - Annecy Jean Jacquemier
LAPP - Annecy Yannis Karyotakis
LAPP - Annecy Inocencio Monteiro
LAPP - Annecy Fabrice Peltier
LAPP - Annecy Julie Prast
LAPP - Annecy Jean Tassan
LAPP - Annecy Guillaume Vouters
LLR - Palaiseau  


Hadronic RPC Detector ReadOut Chip, a very front-end readout chip
DIRAC: DIgital Readout Asic for hadronic Calorimeter, a very front-end readOut chip

-- VincentBoudry - 12 Sep 2008

This topic: CALICE > WebHome > CaliceDetectors > SdHCal
Topic revision: r6 - 2009-09-15 - CatherineAdloff
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