CODIF Calibration Status Lynn Kistler Space Science Center UNH Mar 25-27, 2009 Cambridge, UK

CODIF Efficiencies Overall Change in H+ Efficiency Changes. l For SC4 (FM7) use “monitor rate” data to track the start efficiency (SFR/SR), stop efficiency (SFR/SF) and the fraction of coincidences that also have a single position signal (SEV/SFR). The product of these values gives the total efficiency. l For SC3 (FM6) (for which the Stop rate, SR, does not work well) use comparison spectra with FM7 for time periods when the two spacecraft are close. Overall Change in O+ l We used to use times when the count rate was dominated by O+ (mainly times with O+ “beams” in the lobe). l Because these do not now give a sufficiently high count rate, we instead use comparison O+ spectra between SC3 and SC4, and assume that SC3 is constant Relative efficiency change at different positions for SC 3 and SC4, H+ and O+ l Use pitch angle spectra during gyrotropic time periods to normalize the different positions within each instrument. This is done separately for H+ and O+

Temporal Changes There have been no MCP increases since July-Oct 2004

SC4/FM7 Efficiencies start stop Single event 1-yearWhole mission 2007/1/1 2008/5/12001/1/12008/1/1

Total H+ Efficiency for SC4 SC4-linear scaleSC4-log scale

Total H+ Efficiency for SC3 SC3-linear scaleSC3-log scale

Total O+ Efficiency for SC4 SC4-linear scaleSC4-log scale

SC4 H+ Anode Efficiencies

SC3 H+ Anode Efficiencies

Calibration Files New Calibration files have been made that cover 2006 and This includes l updates to HS H+ total and position efficiencies l updates to HS O+ total and position efficiencies We have done the following checks l Comparison of moments in plasma sheet - spot checks and statistical averages (average velocities, densities) l Checks on LS at times when instrument switches from LS to HS l Absolute Calibration Tests –Comparisons with Whisper (not for recent data) –Pressure balance tests in the plasma sheet

Density comparison over 3 orbits (SC3: Blue - SC4-Black)

Checks on H+ Calibrations GSE - Whole instrument Main point is that the average SC4 Vz is zero, as would be expected. This shows that the anodes are well calibrated for this period. SC3 cannot measure Vz one half of the “high side” does not work. [So ignore SC3 in these plots]

Checks on H+ Calibrations GSE - Whole instrument Main point is that the average SC4 Vz is zero, as would be expected. This shows that the anodes are well calibrated for this period. SC3 cannot measure Vz one half of the “high side” does not work. [So ignore SC3 in these plots]

Checks on H+ Calibrations Instr. Coord. - Half instrument Using the half- instrument from SC3 and SC4, densities and all components of the velocity agree well. Note Vx and Vy (spin plane) average to zero, but Vz is anomalously high because only 1/2 the anodes are used.

Checks on H+ Calibrations Instr. Coord. - Half instrument

LS Calibration Checks at LS/HS transition

LS Calibration Checks at LS/HS transition

Absolute Calibration Comparisons with Whisper (for high density times) Pressure Balance across the plasma sheet

SC4 Low Side in the magnetosheathCODIF/Whisper Comparisons

SC1 High Side in the cusp CODIF/Whisper Comparisons

SC4 High Side in the cusp CODIF/Whisper Comparisons

Masson et al., 2008 SC4 High Side in dense plasma sheetCODIF/Whisper Comparisons

SC1 High Side in more normal plasma sheet CODIF/Whisper Comparisons 30-jul-2002

2002 Plasma sheet Pressure Balance Tests Black - SC4 CODIF, Blue+Red SC1/3 HIA Particle Magnetic Total P

Plasma sheet Pressure Balance Tests Black - SC4 CODIF, Blue+Red SC1/3 HIA Particle Magnetic Total P

Plasma sheet Pressure Balance Tests Black - SC4 CODIF, Blue+Red SC1/3 HIA Particle Magnetic Total P

Plasma sheet Pressure Balance Tests Black - SC4 CODIF, Blue+Red SC1/3 HIA Particle Magnetic Total P 2007

Efficiency Summary Efficiencies have been checked through Jan SC4 shows a significant decline at the end of We need to increase MCP voltage. Calibrated data in CAA (goes through 2005) is good, both in relative and absolute efficiency (from both Whisper comparisons and pressure tests) For l Anode efficiencies are good (Vz looks nominal) l HS/LS comparison looks good l SC3/SC4 comparisons look good. l The Absolute efficiency still looks too high (pressure coming out too low). This needs to be adjusted before release.

The End