Документ взят из кэша поисковой машины. Адрес оригинального документа : http://xmm.vilspa.esa.es/calibration/documentation/epic_cal_meetings/200605/MKirsch_burst.pdf Дата изменения: Wed May 14 13:10:33 2014 Дата индексирования: Wed Apr 13 13:27:28 2016 Кодировка: Поисковые слова: gro j1655-40

EPIC

ESAC

Energy calibration refinement of the EPIC-pn Burst mode
M.G.F. Kirsch1, E. Kendziorra2, G. Sala3, G. Winroth1,4
2

ESA XMM-SOC, ESAC Spain IAAT, University of Tuebingen, Germany 3 MPE, Munich, Germany 4 University LinkЖpings, Sweden

1

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 1


Burst mode ground cal
1,045 1,040

EPIC · ·

ESAC

peakposition_sw/peakposition_burst

1,035 1,030 1,025 1,020 1,015 1,010 1,005 1,000 0,995 0 2000 4000

real data Boltzman fit of Data1_B faked for smoothing reasons y = A2 + (A1-A2)/(1 + exp((x-x0)/dx))

·
6000 8000

energy in eV
SW POS1 SW POS2 FFnc Energy (10 single s/s) (10 single s/s) (10 single s/s) Target in eV Me ssz e it in Me ssz e it in Me ssze it in
O Fe-L Cu-L Mg-K Al-K Si-K Mo-L Ag-L Ti-K Fe-K Cu-K 525 705 930 1254 1487 1740 2293 2984 4511 6404 8048 min 16,7 16,7 16,7 16,7 16,7 16,7 0, 0 0, 0 16,7 16,7 16,7 min 23,3 23,3 23,3 23,3 23,3 23,3 0, 0 0, 0 23,3 23,3 23,3 min 23,3 23,3 23,3 23,3 23,3 23,3 0, 0 0, 0 23,3 23,3 23,3

6 working days measurement CTI/Gain correction was derived by adjusting the burst mode data with a tuning function to SW mode data using ground calibration monochromatic line measurements But that camera was finally not launched
Offset Zeit in min
40,0 40,0 40,0 40,0 40,0 40,0 0, 0 0, 0 40,0 40,0 40,0 Summe in min Summe in h Summe in wday s

faktor
1,8 1,8 7,3 6,0 17,0 17,0 15, 2 15, 4 11,5 2,9 5,0 100,9

SW POS2 Burst POS2 (10*f single s/s) (10*f single s/s) Me ssz e it in Me ssz e it in min min 13,0 308,6 13,0 308,6 3,2 76,1 3,9 92,6 1,4 32,7 1,4 32,7 0, 0 0, 0 0, 0 0, 0 2,0 48,3 8,0 191,6 4,7 111,1

Zeit in min
426, 426, 189, 205, 154, 154, 15, 15, 165, 305, 224, 7 7 9 8 4 4 2 4 2 9 1

Schlitz messungen in Camex-NДhe z ur Untersuchung Amplification & CTE im Burst & SW Mode

2182,8 36,4 6,06

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 2


results with ground tuning function for real data from CRAB observation

EPIC

ESAC

residuals @ edges 2.2 % 2.5 %

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 3


Burst mode CTI correction

EPIC

ESAC

· Orbit data of the Crab have then been used to redefine that tuning function 0 01 e2 c sin trying to reduce the ted n residuals around Si me ple im and Au edges ion t · old Burst tua Si · new Burst · SW · Energy calibration is believed correct within 5 %
Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 4


possible improvement

EPIC

ESAC

· Further improvement can only be achieved using line rich SNR observation · Idea: observe Cas-A in FF/SW and Burst mode and adjust Burst mode according to the different line-positions found · Problem: Lifetime in Burst mode is only 3 % targeting the same number of events as for FF (12 ks) would blow up the exposure time for burst to 400 ks · But we do not need the same number of events, we just need to determine the line positions with an acceptable error (that goes with 1/sqrt(N))
Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 5


error estimate rel. to FF
25
expected error factor

EPIC

ESAC

20 15 10 5 0 0 10 20 30 40 50 exposure time [ksec] assuming a 12 ks FF mode observation

errorBurst errorFF =

N N

FF

Burst

N FF N Burst
3 100

c TFF = c TBurst .

· Error of line determination scales with sqrt(N)

TFF = 5 .7 TBurst

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 6


error simulation

EPIC

ESAC

12 ks FF simulated 30 ks Burst

0.6 0.5

FF 12 ks

Sim_Burst 30 ks

· only CCD4 events · simulated errors for determination of line position for a 30 ks Burst observation · Burst errors: ~ factor of 3 larger · Agrees with estimate

e r ro r in %

0.4 0.3 0.2 0.1 0 1000 3000 5000 7000

FF en ergy [eV]
Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 7


strategy for cal improvement
· recalibrate gain-tuning for Burst

EPIC

ESAC

­ 15 ks: Cas-A FF or FF or SW as reference ­ 40 ks: Cas-A Burst ­ (Perhaps in addition a source with more low energy lines)

· in addition CTE rate calibration

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 8


CTE rate dependence
· · ·

EPIC

ESAC

Effect less than 2 % Results not consistent Need to improve statistics

­ GX339-4 observation in archive (ODF with problems, currently mot available) ­ TOO NRCO on point source with flux > 1 Crab 30 ks ­ In addition accepted AO5 G. Sala Proposal on GRO J1655-40 (will be observed if source is in bright state (> 1, > 2 Crab)

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 9


further proceeding

EPIC

ESAC

1. NRCO for the retuning of the CTI/Gain using Cas-A (if you agree?) 2. rate calibration refining the precursor calibration of the general EPIC-pn CTI correction after 1)

Marcus Kirsch, XMM-Newton European Space Astronomy Center Page 10