Detectors of charged particles and ions 1) Gas filled detectors a) Ionization chambers b) Proportional counters c) Multiwire chambers d) Time projection chambers 2) Scintillation detectors 3) Semiconductor detectors Mostly high efficiency (ionization will start immediately), big enough detector – absorption of whole energy Silicon detectors of alpha particles produced by CAMBERA company Hadron calorimeter of NA49 experiment Calorimeter of ATLAS experiment

Scintillation detectors A – absolute scintillation efficiency, kB – parameter which joins density of ionization centers with ionization Semiempirical Birks equation: Response on heavy charged particles: Non-linearity for L = f(E) starts to manifest Response of fast plastic scintillator on heavy ions Limited number of scintillation centers → saturation – part of energy is not converted (mainly for organic scintillator) saturation: Many other variants of semiempirical equations Dependency of light output on ionization losses Dependency of light output on kB Total light output L:

Differentiation of different ions by means of analysis of puls shape: Short and long components of de-excitation – de-excitation of different excited states (ratio of their excitation probability depends on ionization losses) Possibility to use two types of scintillator with different de-excitation time Differentiation by means of comparison of light outputs with different time window: BaF 2 spectrometer TAPS (right) and CsI(Tl) (left) L(short) L(long) Dependency of response on energy for plastic scintillator NE102A ΔE-E telescopes 2 mm plastic and CsI scintillator

Compensation calorimeter: Hadron calorimeters Transversal energy flow and longitudinal energy flow – escape from detector Bigger response to particles of elmg component L e /L h = 1,1 – 1.35 Suitable active and passive calorimeter parts: L e /L h ≈ 1 Possibility of correction during later analysis – usage of information about course of shower 238 U – absorption of slow neutrons, shielding from soft photons by layers of materials with small Z Absorption of photons from neutron captures by means of atoms with large Z End of hadron shower E ~ E THR (π) ~ 100 MeV – threshold of π mesons production Detection of large amount of created neutrons (5 neutrons/GeV), their energies ~ 8 MeV Uncertainty consists of three components: 1) statistical fluctuations: 2) detector – noise, pedestals: 3) calibration – photomultiplier nonlinearity, in homogeneities: Forward calorimeter of ALICE experiment