One of my research interests is related to neutrinos from the atmosphere and beyond, and their detection. Neutrinos are of particular interest at the moment because of the recent results of the SuperKamiokande experiment. In this underground experiment, the rates of muon neutrinos arriving at the detector are not matching theoretical calculations, although the electron neutrino rates are. A reasonable solution to this discrepancy is that muon neutrinos are massive and are "disappearing" because they are converting into tau neutrinos during their passage through the earth. Important here are the distance scales (comparable to the earth's diameter) for neutrino energies on the order of 1-10 GeV. The source of the neutrinos for this experiment are "atmospheric neutrinos", neutrinos produced by cosmic ray interactions with air nuclei.
Currently, my work with Stefan Kretzer has been directed to a better theoretical understanding of the deep-inelastic scattering piece of the neutrino nucleon cross section, including target mass and charm mass corrections, as well as lepton mass correction terms relevant to tau neutrino scattering. Our first paper is "Tau neutrino deep inelastic charged current interactions," Physical Review D 66 (2002) 113007
My neutrino research has also been focused on higher energies than those directly relevant to the SuperKamiokande experiment, but which may give us further information about whether the oscillation hypothesis is correct. My research requires particle physics from several different arenas. For the total neutrino-nucleon cross section, HERA extraction of parton distribution functions at low-x have implications for the ultrahigh energy neutrino-nucleon cross section, as discussed in our article published in Astroparticle Physics 5 (1996) 81-110 and updated in Phys. Rev. D58 (1998) 093009.
Together with Lara Pasquali and Ina Sarcevic, I have reevaluated the flux of muons and neutrinos from charmed particles produced in cosmic ray-air collisions. For the evaluation of charmed particle production, we used the next-to-leading order calculation of the charm production cross section. Our work appears in: hep-ph/9710363 (Astropart. Phys. 9 (1998) 193), hep-ph/9711457 (Nucl. Phys. Proc. Suppl. 70 (1999) 361), and Physical Review D59 (1999) 034020. The tau neutrino flux calculation appears in Pasquali and Reno, Physical Review D59 (1999) 093003.
More recently, Ina Sarcevic, Sharada Iyer and I have evaluated numerically the effect of tau neutrino interaction in the earth on the flux of tau neutrinos arriving at underground detectors, and implications for tau neutrino detection. A series of papers appear in Physical Review D61 (2000) 053003, Physical Review D62 (2000) 123001, Physical Review D64 (2001) 093003.
A related topic is nonstandard model contributions to neutrino cross sections and the implications for horizontal air showers. We have considered mini-black hole production.
Off the topic of neutrinos, perturbative QCD corrections in collider experiment processes have been another area of interest, most recently "Next-to-leading order slepton pair production at hadron colliders," with H. Baer and B. W. Harris. This appears in Physical Review D57 (1998) 5871.