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I stuck with integral fluxes, for >100 MeV, >300 MeV, >1 GeV, and >3 GeV
energy ranges, with uncertainties included for each flux. This will still be useful for finding unusual spectra.
(Ballet) The advantage I see in band-limited fluxes is that they are approximately independent.
In addition, your scheme introduces a confusion in the user's mind, because the main flux > 100 MeV that we provide (FLUX100) is NOT directly comparable to those integral fluxes. It is NOT obtained by selecting photons above 100 MeV, but is simply a representation of the source flux obtained by fitting the entire spectral range, adjusting the spectral index.
If we adopt your scheme, then we must go all the way, add a FLUX30 column which will be used for the full range, obtain FLUX100 from events > 100 MeV only, and adjust the spectral index (when it is possible) in all 'bands'. Then all the 'bands' will have the same meaning.
5. Flux_History
(Ballet) Did anybody study what was the best energy interval (in particular the lower boundary) to look for variability? Is 100 MeV indeed the best trade-off between number of source photons and number of background photons plus contamination by other sources ?
(Digel) This has not been studied, to my knowledge. Certainly 100 MeV is not the best in terms of being able to distinguish sources. Quoting fluxes for the range >100 MeV, though, is common.
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XTENSION 'BINTABLE' Extension type
BITPIX 8 Bits per pixel - assume single precision floating point
NAXIS 2 # of axes=2
NAXIS1 ### Number of bytes per row
NAXIS2 ### Number of point sources in file (~1e4)
TFIELDS 27 Number of fields per row
CHECKSUM Checksum for entire HDU
DATASUM Checksum for data table
TELESCOP 'GLAST' Name of mission generating data
INSTRUME 'LAT'
EXTNAME 'LAT_Point_Source_Catalog' Name of the extension
TIMESYS 'TT' Time system used in time keywords
MJDREF 51910 MJD date of reference epoch
TIMEUNIT 's' Time unit used in TSTART, TSTOP and TZERO keywords
TSTART ### Time of start of observation offset from TZERO in units of TIMEUNIT
TSTOP ### Time of end of observation offset from TZERO in units of TIMEUNIT
HDUCLASS 'OGIP ' Format conforms to OGIP standard
HDUDOC '?'
HDUVERS '1.0.0 '
HDUCLAS1 'SRCLIST' ?
TTYPE1 'Source_Name' Source name in standard format, e.g., 1GL J123456-012345
TFORM1 '18A ' Character string
TUNIT1 'none' Units of field
TTYPE2 'RA'
TFORM2 '1E ' Floating point
TUNIT2 'deg'
TLMIN2 0.0 Minimum value
TLMAX2 360.0 Maximum value
TTYPE3 'DEC' DEC
TFORM3 'E ' Floating point
TUNIT3 'deg'
TLMIN3 -90.0 Minimum value
TLMAX3 90.0 Maximum value
TTYPE4 'Conf_68_SemiMajor' Semimajor axis, 68% containment confidence region
TFORM4 '1E ' Floating point
TUNIT4 'deg'
TLMIN4 0.0 Minimum value
TLMAX4 360.0 Maximum value
TTYPE5 'Conf_68_SemiMinor' Semiminor, axis, 68% containment confidence region
TFORM5 '1E ' Floating point
TUNIT5 'deg'
TLMIN5 0.0 Minimum value
TLMAX5 360.0 Maximum value
TTYPE6 'Conf_68_PosAng' Position angle, 68% containment confidence region, E of N
TFORM6 '1E ' Floating point
TUNIT6 'deg'
TLMIN6 0.0 Minimum value
TLMAX6 360.0 Maximum value
TTYPE7 'Conf_95_SemiMajor' Semimajor axis, 95% containment confidence region
TFORM7 '1E ' Floating point
TUNIT7 'deg'
TLMIN7 0.0 Minimum value
TLMAX7 360.0 Maximum value
TTYPE8 'Conf_95_SemiMinor' Semiminor, axis, 95% containment confidence region
TFORM8 '1E ' Floating point
TUNIT8 'deg'
TLMIN8 0.0 Minimum value
TLMAX8 360.0 Maximum value
TTYPE9 'Conf_95_PosAng' Position angle, 95% containment confidence region, E of N
TFORM9 '1E ' Floating point
TUNIT9 'deg'
TLMIN9 0.0 Minimum value
TLMAX9 360.0 Maximum value
TTYPE6 'Flux100' Average photon flux >100 MeV
TFORM6 '1E ' Floating point
TUNIT6 'cm**(-2) s**(-1)'
TLMIN6 0.0 Minimum value
TLMAX6 ### Maximum value
TTYPE7 'Unc_Flux100' Uncertainty (1-sigma) in average flux >100 MeV
TFORM7 '1E ' Floating point
TUNIT7 'cm**(-2) s**(-1)'
TLMIN7 0.0 Minimum value
TLMAX7 ### Maximum value
TTYPE8 'Spectral_Index' Photon spectral index, >100 MeV
TFORM8 '1E ' Floating point
TUNIT8 'none' Dimensionless
TLMIN8 -10.0 Minimum value
TLMAX8 10.0 Maximum value
TTYPE8 'Unc_Spectral_Index' 1-sigma uncertainty, photon spectral index
TFORM8 '1E ' Floating point
TUNIT8 'none' Dimensionless
TLMIN8 0.0 Minimum value
TLMAX8 10.0 Maximum value
TTYPE9 'Flux300' Average flux >300 MeV
TFORM9 '1E ' Floating point
TUNIT9 'cm**(-2) s**(-1)'
TLMIN9 0.0 Minimum value
TLMAX9 1.0 Maximum value
TTYPE10 'Unc_Flux300' Uncertainty (1-sigma) in average flux >300 MeV
TFORM10 '1E ' Floating point
TUNIT10 'cm**(-2) s**(-1)'
TLMIN10 0.0 Minimum value
TLMAX10 1.0 Maximum value
TTYPE11 'Flux1000' Average flux >1000 MeV
TFORM11 '1E ' Floating point
TUNIT11 'cm**(-2) s**(-1)'
TLMIN11 0.0 Minimum value
TLMAX11 1.0 Maximum value
TTYPE12 'Unc_Flux1000' Uncertainty (1-sigma) in average flux >1000 MeV
TFORM12 '1E ' Floating point
TUNIT12 'cm**(-2) s**(-1)'
TLMIN12 0.0 Minimum value
TLMAX12 1.0 Maximum value
TTYPE13 'Flux3000' Average flux >3000 MeV
TFORM13 '1E ' Floating point
TUNIT13 'cm**(-2) s**(-1)'
TLMIN13 0.0 Minimum value
TLMAX13 1.0 Maximum value
TTYPE14 'Unc_Flux3000' Uncertainty (1-sigma) in average flux >3000 MeV
TFORM14 '1E ' Floating point
TUNIT14 'cm**(-2) s**(-1)'
TLMIN14 0.0 Minimum value
TLMAX14 1.0 Maximum value
TTYPE15 'Variability_Index' Flux variability index (TBD)
TFORM15 '1E ' Floating point
TUNIT15 'none' Dimensionless
TLMIN15 ### Minimum value
TLMAX15 ### Maximum value
TTYPE16 'Signif_Avg' Detection significance (whole time interval)
TFORM16 '1E ' Floating point
TUNIT16 'none' Dimensionless
TLMIN16 0.0 Minimum value
TLMAX16 1.0E9 Maximum value
TTYPE17 'Signif_Peak' Detection significance (peak)
TFORM17 '1E ' Floating point
TUNIT17 'none' Dimensionless
TLMIN17 0.0 Minimum value
TLMAX17 1.0E9 Maximum value
TTYPE18 'Flux_Peak' Peak flux (>100 MeV) for time interval above
TFORM18 '1E ' Floating point
TUNIT18 'cm**(-2) s**(-1)'
TLMIN18 0.0 Minimum value
TLMAX18 1.0 Maximum value
TTYPE19 'Unc_Peak_Flux' Uncertainty (1-sigma) in peak flux >100 MeV
TFORM19 '1E ' Floating point
TUNIT19 'cm**(-2) s**(-1)'
TLMIN19 0.0 Minimum value
TLMAX19 1.0 Maximum value
TTYPE20 'Time_Peak' Center of time interval of peak significance
TFORM20 '1D ' Double precision
TUNIT20 's'
TLMIN20 0.0 Minimum value
TLMAX20 ### Maximum value
TZERO20 ###
TTYPE21 'Peak_Interval' Duration of time interval of peak significance
TFORM21 '1D ' Double precision
TUNIT21 's'
TLMIN21 0 Minimum value
TLMAX21 ### Maximum value
TTYPE22 'Flux_History' Flux (>100 MeV) history (monthly)
TFORM22 '12E ' Floating point array, 12 months
TUNIT22 'cm**(-2) s**(-1)'
TLMIN22 -1.0 Minimum value
TLMAX22 1.0 Maximum value
TTYPE23 'Flux_Unc_History' Flux uncertainty (1-sigma, >100 MeV) history
TFORM23 '12E ' Floating point array, 12 months
TUNIT23 'cm**(-2) s**(-1)'
TLMIN23 0.0 Minimum value
TLMAX23 1.0 Maximum value
TTYPE24 'Hist_Start' Start of time intervals of flux history
TFORM24 '12E ' Floating point array
TUNIT24 's'
TLMIN24 0.0 Minimum value
TLMAX24 ### Maximum value
TZERO24 ###
TTYPE25 'ID_Counterpart' Source counterpart (if any)
TFORM25 '20A ' Character string
TUNIT25 'none' Dimensionless
TTYPE26 'Conf_Counterpart' Confidence of association of counterpart with source
TFORM26 '1I ' Index, 1 = Figure of Merit, 2 = Correlated variability
TUNIT26 'none' Dimensionless
TLMIN26 0 Minimum value
TLMAX26 2 Maximum value
TTYPE27 'Flags' Flags (TBD) for catalog entry
TFORM27 '1I '
TUNIT27 'none' Dimensionless
END
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