We report preliminary results on the analysis of the three-body Υ( 10860) → B Bπ, Υ(10860) → [B B * + c.c.]π and Υ(10860) → B * B * π decays including an observation of the Υ(10860) → Z ± b (10610)π ∓ → [B B * + c.c.] ± π ∓ and Υ(10860) → Z ± b (10650)π ∓ → [B * B * ] ± π ∓ decays as intermediate channels. We measure branching fractions of the three-body decays to be B(Υ(10860) → [B B * + c.c.] ± π ∓ ) = (28.3 ± 2.9 ± 4.6) × 10 −3 and B(Υ(10860) → [B * B * ] ± π ∓ ) = (14.1 ± 1.9 ± 2.4) × 10 −3 and set 90% C.L. upper limit B(Υ(10860) → [B B] ± π ∓ ) < 4.0 × 10 −3 . We also report results on the amplitude analysis of the three-body Υ(10860) → Υ(nS)π + π − , n = 1, 2, 3 decays and the analysis of the internal structure of the three-body Υ(10860) → h b (mP )π + π − , m = 1, 2 decays. The results are based on a 121.4 fb −1 data sample collected with the Belle detector at a center-of-mass energy near the Υ(10860).

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An analog hadron calorimeter (AHCAL) prototype of 5.3 nuclear interaction lengths thickness has been constructed by members of the CALICE Collaboration. The AHCAL prototype consists of a 38-layer sandwich structure of steel plates and highly-segmented scintillator tiles that are read out by wavelength-shifting fibers coupled to SiPMs. The signal is amplified and shaped with a custom-designed ASIC. A calibration/monitoring system based on LED light was developed to monitor the SiPM gain and to measure the full SiPM response curve in order to correct for non-linearity. Ultimately, the physics goals are the study of hadron shower shapes and testing the concept of particle flow. The technical goal consists of measuring the performance and reliability of 7608 SiPMs. The AHCAL was commissioned in test beams at DESY and CERN. The entire prototype was completed in 2007 and recorded hadron showers, electron showers and muons at different energies and incident angles in test beams at CERN and Fermilab.

A prototype Silicon-Tungsten electromagnetic calorimeter (ECAL) for an International Linear Collider (ILC) detector was installed and tested during summer and autumn 2006 at CERN. The detector had 6480 silicon pads of dimension 1×1 cm 2 . Data were collected with electron beams in the energy range 6 to 45 GeV. The analysis described in this paper focuses on electromagnetic shower reconstruction and characterises the ECAL response to electrons in terms of energy resolution and linearity. The detector is linear to within approximately the 1% level and has a relative energy resolution of (16.6 ± 0.1)/ E(GeV) ⊕ 1.1 ± 0.1 (%). The spatial uniformity and the time stability of the ECAL are also addressed.

The CALICE collaboration is studying the design of high performance electromagnetic and hadronic calorimeters for future International Linear Collider detectors. For the hadronic calorimeter, one option is a highly granular sampling calorimeter with steel as absorber and scintillator layers as active material. High granularity is obtained by segmenting the scintillator into small tiles individually read out via silicon photo-multipliers (SiPM). A prototype has been built, consisting of thirty-eight sensitive layers, segmented into about eight thousand channels. In 2007 the prototype was exposed to positrons and hadrons using the CERN SPS beam, covering a wide range of beam energies and angles of incidence. The challenge of cell equalization and calibration of such a large number of channels is best validated using electromagnetic processes. The response of the prototype steel-scintillator calorimeter, including linearity and uniformity, to electrons is investigated and described.