SNO Periodicity Analyses


A Search for Periodicities in the 8B Solar Neutrino Flux Measured by the Sudbury Neutrino Observatory (hep-ex/0507079, submitted to Physical Review D)


The following data are available for download:

1) Exact run start times and run lengths for D2O and salt phase runs
The data files are in ASCII format, and the header text of each file explains the format.
WARNING: The start and stop times of SNO's runs, while irregular, do contain periodic structure (for example, a 7-day modulation associated with SNO's weekly work schedule can be extracted from the run boundary times).  Any periodicity analysis that does not take into explicit account the actual start and stop times of each run, and the actual distribution of livetime on each calendar date, may be suspect.  These files indicate the exact time intervals over which the SNO detector was taking solar neutrino data, and should be explicitly included in any periodicity analysis.

2)  Event times for neutrino events, truncated to the day (1-day binning)
For each event, the date on which that event occurred is given.  At present the SNO collaboration is not releasing the time of day for each event, since we are pursuing day-night and other time variability analyses that could be compromised by release of this additional information.  However, the unbinned maximum likelihood analysis used in SNO's periodicity paper did include the exact event times.

Contact person: Scott Oser
August 15, 2005