H. F-W. Sadrozinski

Research summary

Contributions span silicon detector instrumentation and charmonium spectroscopy from the Crystal Ball detector at SPEAR. A conceptual design for proton computed tomography (pCT) combines a silicon-based particle-tracking system with a crystal calorimeter to measure individual-proton energy loss, with the goal of improving dose calculation for proton therapy and enabling pre-treatment verification of patient positioning [1]. Ultra-Fast Silicon Detector (UFSD) work, based on the Low-Gain Avalanche Detector design with n-on-p silicon and an internal thin low-resistivity multiplication layer, established 4D tracking with simultaneous spatial and ~10s of picoseconds timing resolution [3]; beam-test measurements with 180 GeV/c pions on 45-µm UFSDs reported gains from 5 to 70 (bias-dependent) and a 16 ps timing resolution measured against a quartz/SiPM reference [4]. Earlier Crystal Ball work measured charmed-D-meson absolute branching fractions at the psi(3770) by full DDbar event reconstruction, with later reanalysis addressing Cabibbo-suppressed and multi-pi0 backgrounds and reducing prior branching fractions by 21–24 percent while leaving ratios largely unchanged [2][5]. Charmonium spectroscopy from the Crystal Ball yielded measurements of psi' -> gamma gamma J/psi radiative cascades and the chi_2,1,0 states [6], evidence for a 2++ eta-eta resonance theta(1640) in J/psi -> gamma eta eta with Gamma ≈ 220 MeV [7], and observation of a narrow xi(2230) state in J/psi -> gamma K-Kbar [8]. Inclusive photon spectra from 1.8 × 10^6 psi' and 2.2 × 10^6 J/psi decays provided systematic measurements of radiative transition energies and branching ratios in the charmonium system [9].

Recent publications

1. Conceptual design of a proton computed tomography system for applications in proton radiation therapy2004 · IEEE Transactions on Nuclear Science · 216 citationsDOI
2. Reanalysis of Charmed-D-Meson Branching Fractions1988 · Physical Review Letters · 214 citationsDOI
3. 4D tracking with ultra-fast silicon detectors2017 · Reports on Progress in Physics · 214 citationsDOI
4. Beam test results of a 16 ps timing system based on ultra-fast silicon detectors2017 · Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment · 174 citationsDOI
5. Direct Measurements of Charmed-D-Meson Hadronic Branching Fractions1986 · Physical Review Letters · 173 citationsDOI
6. Design optimization of ultra-fast silicon detectors2015 · Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment · 157 citationsDOI
7. Study of the reactionψ′→γγJψ1982 · Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields · 143 citationsDOI
8. Evidence for anηηResonance inJψRadiative Decays1982 · Physical Review Letters · 139 citationsDOI
9. Observation of a narrowKK¯state inJ/ψradiative decays1986 · Physical Review Letters · 134 citationsDOI
10. Charmonium spectroscopy from inclusive ψ’ andJ/ψradiative decays1986 · Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields · 129 citationsDOI

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External profiles

• ORCID: https://orcid.org/0000-0003-0019-5410
• OpenAlex: openalex.org

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