Office: Wean Hall 8406
Ph.D., Massaschusetts Institute of Technology
ResearchQuark interaction physics explores sub-atomic particle systems at the boundary between the quark-gluon and meson-baryon descriptions of matter. The field addresses questions that, as a practical matter, do not require the highest beam energies or luminosities, but do call for high-precision measurements using specialized equipment. At Carnegie Mellon we have a large research group doing Quark Interaction Physics.
Currently, my main area of work is in the electromagnetic production of strange particles (kaons and hyperons). The production of strange-quark pairs via the well-known electromagnetic interaction gives us an avenue for refining our knowledge of baryon resonances, coupling constants, and polarization observables; the results are compared with modern quark models and with unitarized chiral perturbation theory. This work is being done at the Thomas Jefferson National Accelerator Facility. More exactly, my experimental work is done using the CEBAF Large Acceptance Spectrometer (CLAS) in Hall B and using the GlueX detector (GlueX) in Hall D at Jefferson Lab.
- R. Dickson, R. A. Schumacher, et al., Photoproduction of the f1(1285) meson (CLAS Collaboration) Physical Review C 93, 065202 (2016)
- K. Moriya et al., Spin and parity measurement of the Λ(1405) baryon, Physical Review Letters 112, 82004 (2014)
- K. Moriya et al., Differential photoproduction cross sections of the Σ0(1385), Λ(1405), and Λ(1520), Phys. Rev. C 88, 45201 (2013)
- K. Moriya et al., Measurement of the Σπ photoproduction line shapes near the Λ(1405), Phys. Rev. C 87, 35206 (2013)
- G Bernero, J Olitsky, R A Schumacher, Atmospheric dependence of the stopping cosmic ray muon rate at ground level, J. Phys. G: Nucl. Part. Phys. 40, 65203 (2013)
- R. A. Schumacher, M. M. Sargsian, Scaling and resonances in elementary K+Λ photoproduction, Physical Review C 83, 025207 (2011)
- R. Schumacher, Polarization in hyperon photo- and electro-production, The European Physical Journal A 35, 299 (2008)
- R. Bradford et al., First measurement of beam-recoil observables Cx and Cz in hyperon photoproduction, Physical Review C 75, 035205 (2007)
- R. Bradford et al., Differential cross sections for γ+p→K++Y for Λ and Σ0 hyperons, Physical Review C 73, 035202 (2006)
- Reinhard Schumacher, The Rise and Fall of Pentaquarks in Experiments, AIP Conf. Proc. 842, 409 (2006).
- J. McNabb et al., Hyperon photoproduction in the nucleon resonance region, Physical Review C 69, 042201 (2004)
- R. A. Schumacher, Strangeness production and other recent results from Hall B at Jefferson Lab, The European Physical Journal A - Hadrons and Nuclei 18, 371 (2003)
- B.A. Mecking et al., The CEBAF large acceptance spectrometer (CLAS), Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 503, 513 (2003)
- Stephan A. Roth, Reinhard A. Schumacher, A computer-controlled tension monitoring system for drift chamber wires, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 369, 215 (1996)
- Reinhard A. Schumacher, Possible violation of the rule in non-mesonic hypernuclear weak decay, Nuclear Physics A 547, 143 (1992)
- Reinhard A. Schumacher, Special relativity and the Michelson–Morley interferometer, American Journal of Physics 62, 609 (1994)