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The division of responsibilities between different institutions in the Whipple Gamma Ray Collaboration are listed below; however these are only guidelines and the divisions are not hard and fast. The observing program is agreed upon by the collaboration in biannual meetings in which all groups are represented. The observing mode and data reduction method to be used is also agreed upon at that time. The ongoing observing program is the prime responsibility of the local Smithsonian group (aided by the resident lSU postdoc, David Bird). This involves the detailed scheduling of observing (sources and observers). Fast-look analysis is performed locally and the data is prepared for distribution to the five other centers. The local group is responsible for routine maintenance of the telescopes and cameras. Observing is shared by all groups with visiting observers sharing shifts with local staff. Responsibility for data reduction on specific sources is assumed by individuals within the collaboration. Usually students are assigned specific sources for dissertation studies. Data on each source is independently reduced by at least two observers. New data reduction methods are developed and distributed for routine analysis. Some centers take responsibility for specific tasks e.g. spectrum analysis (ISU, Leeds), periodicity analysis (Michiga;n, Leeds), etc. Technical aspects of the experiment are the responsibility of the individual groups e.g. 11m electronics (Michigan), 10m electronics (SAO), phototubes (ISU), cabling (Purdue), tracking control, ccd cameras (UCD), data acquisition software (Leeds), CAMAC interface (Purdue), data acquisition upgrades (ISU), 10m optics (SAO), 11m optics (ISU, Michigan), etc. Simulations were originally the responsibility of lSU and Leeds; they are now carried out at all centers. Long-term planning has been the responsibility of Purdue. All groups are involved in the design studies for the Phase I development. Progress Reports: Science The May 1994 Markarian Flare at Whipple and EGRET Energies Since its discovery by us at TeV energies (Punch et al. 1992), we have continued a program of monitoring the emission from Markarian 421, coordinated with observations taken by the EGRET detector. (These coordinated observations are partially supported by NASA Gamma Ray Observatory guest investigator grants.) In May 1994, an outburst was detected in which the intensity of the source increased by nearly an order-of-magnitude over its pre-outburst, "quiescent" level. A paper describing these results has now been accepted for publication in the Astrophysical Journal Letters, and a copy in included in the appendix.

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Cosmic-ray electrons and positrons (CREs) at GeV-TeV energies are a unique probe of our local Galactic neighborhood. CREs lose energy rapidly via synchrotron radiation and inverse-Compton scattering processes while propagating within the Galaxy and these losses limit their propagation distance. For electrons with TeV energies, the limit is on the order of a kiloparsec. Within that distance there are only a few known astrophysical objects capable of accelerating electrons to such high energies. It is also possible that the CREs are the products of the annihilation or decay of heavy dark matter (DM) particles. VERITAS, an array of imaging air Cherenkov telescopes in southern Arizona, USA, is primarily utilized for gamma-ray astronomy, but also simultaneously collects CREs during all observations. We describe our methods of identifying CREs in VERITAS data and present an energy spectrum, extending from 300 GeV to 5 TeV, obtained from approximately 300 hours of observations. A single power-law fit is ruled out in VERITAS data. We find that the spectrum of CREs is consistent with a broken power law, with a break energy at 710 ± 40 stat ± 140 syst GeV.