GENEVAC: An Application for Calculating, Viewing and Storing
Gamma-ray Burst Data
Sam StaffordThe Ohio State University
Department of Physics
GRB Temporal Analysis WorkshopLos Alamos, NM
August 29-31, 2011
Overview
• Summary of GENEVAC application• Live Demo• HTML output• Possible extensions
Motivation
• Over 5,000 bursts recorded since 1970’s• Multiple instrument sources; numerous observable
parameters• Need for versatile, modular platform• Common, user-readable format for GRB data to
facilitate multiple analyses:– Lightcurves and spectra (prompt, afterglow)– Neutrino emission– Lags– Variability
• Database of GRB object data• Graphical program for parameter calculation
and plotting:• Light curve• Electromagnetic spectra• Neutrino spectra
• Modular design / extensibility• Lag / variability• Afterglow
GENEVACGamma-ray-burst Electromagnetic and Neutrino
Emission Viewer And Calculator
Graphical User Interface
• Gamma-ray lightcurves – Multiple energy-band display– User-selectable bin size– Background subtraction (polynomial regression)– Drag-and-release zoom– Breakout-window feature on graph displays• Facilitates larger display / easier navigation• Enhanced display controls
Graphical User Interface
• Gamma-ray and neutrino parameters – Parameters can be calculated or entered manually– Up to four simultaneous models– Pre-programmed and User-definable models – Electromagnetic and neutrino energy spectrum
displays– Detector effective area and event rate– Error bars supported in calculations and plots– Graph data can be exported to table
• Read/write to GRB object database
GENEVAC Database
• Stored in user-readable format• Simple keyword structure, can be entered manually
or from the GENEVAC screens.• Designed for multiple instrument data sources
(currently supports BATSE, Swift/BAT, HETE; extensible to Fermi, etc.)
• Currently populated with >70 long bursts from BATSE catalog
• Batch conversion process from native instrument data structure to GENEVAC database
GENEVAC Database
Partial list of valid database keywords:• OBJECT_ID• INSTRUMENT_ID• TRIGGER_NUMBER• RIGHT_ASCENSION• DECLINATION• PEAK_LUMINOSITY• JET_ANGLE• T90_DURATION• BREAK_ENERGY• REDSHIFT• LORENTZ_BOOST
GENEVAC Demo
HTML Output
• Object index page• Individual GRB data page:– Parameter table– Light curves– Electromagnetic and neutrino spectra– Detector effective area– Event counts
Design Considerations• Modular design
– Most functions can be called in batch mode as well as in screen display– Allows separation of components among multiple servers if needed
• Interface-centered design– Allows delegation of computation-intensive tasks– Allows alternate GUI modules (e.g., web client)
• Written in Java™ 6.0, using Java™ Swing GUI utilities (well-known, mature industry standard; short development cycle)
• Object-oriented programming model• Designed to run on any computer with a Java Runtime
Environment (JRE). • Web-based version under consideration
Architecture
GRB Calculation Model
GRB Data Model
Graphical User Interface Lightcurves Parameters Spectra
HTML Utilities
Static web pagesLibraries Data types BG subtraction Utilities
Database Parameter files Temporal data
Externally-defined formalisms(in development)
Web client(proposed)
Future Initiatives
• Afterglow analysis• Additional instruments (e.g. Fermi)• Spectral lag (Cross-correlation function, pulse
fit)• Variability analysis (wavelet, FFT)• Web client• Usability enhancements (e.g., undo stack)
Summary• Database of GRB object data• Graphical program for calculating parameters:
• Lightcurve• Electromagnetic spectra• Neutrino spectra
• HTML output– Object index table– Spectrum, event rate plots
• Modular, extensible design– Web client– Afterglow– Variability analysis