Документ взят из кэша поисковой машины. Адрес оригинального документа : http://xmm.vilspa.esa.es/calibration/documentation/epic_cal_meetings/200704/Plucinsky.pdf Дата изменения: Tue May 13 17:54:46 2014 Дата индексирования: Wed Apr 13 13:20:25 2016 Кодировка: Поисковые слова: molecular cloud

Chandra X-Ray Observatory

CXC

1. ACIS Calibration: Recent Updates, Planned Updates, & Future Issues 2. E0102: Joint Fits with ACIS S3, MOS1/2 & pn

Paul Plucinsky, Joseph DePasquale, & Steve Snowden
Paul Plucinsky 1

EPIC Cal April 2007


Chandra X-Ray Observatory
1. Recent Updates to the ACIS Calibration
CALDB 3.3.0 released on 15 December 2006

CXC

· BI CCD CTI correction for -120 C (S3 & S1), need to have CIAO
3.4 also to apply the correction, BI CTI correction is now part of the standard data processing · Effective area correction around the Si K edge, ~4 % at 1.8 keV · FI CCD ``dead area'' correction to account for the area lost on average in each frame to cosmic rays, 2.5-4.0% as a function of row

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Planned Update: CTI Correction for Graded Mode for FI CCDs · Faint mode CTI correction adjusts the PH of each pixel in the 3x3 event island · In Graded mode, only have x, y position of event, grade, and summed PH · Use grade and summed PH to determine the most likely charge distribution based on ``average'' images · Use this information in an Graded mode CTI correction

CXC

Mn-K flight grade 8 (left split) for S2 Bottom 256 rows Top 256 rows

Vikhlinin (SAO)

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Map of Good and Bad Grades

CXC

Vikhlinin (SAO)
33 of 256 flight grades are included in the ASCA G02346 grades

Create average images for each of these 33 grades for multiple energies

Paul Plucinsky

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EPIC Cal April 2007


CXC Comparison of Graded Mode and Faint Mode CTI Correction

Chandra X-Ray Observatory

PossonBrown (SAO) Graded mode CTI correction provides most of the benefit o f th e F a i n t mode correction Fo r FI CCDs only !
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Paul Plucinsky

EPIC Cal April 2007


Chandra X-Ray Observatory
Continuous Clocking Mode Calibration
External Calibration Source: No CTI correction applied

CXC

Edgar (SAO)
In CC mode: - row-to-row transfer time is different so the effects of CTI are different -- don't know the y position of the events, but for some observations you know the y position of the source

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Update on Contaminant Buildup

CXC

Data: Grant (MIT) Model: O'Dell & Tennant (M S F C )

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Optical Depth Comparison

CXC

C-K Marshall (MIT) inferred optical depth at 700 eV ECS Grant (MIT) Mn L E0102 DePasquale (SAO) OVIII Ly-a

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Future Issues: Focal Plane Operating Temperature

CXC

· current operating temperature is -119.7 C · as the mission has progressed, the frequency and magnitude of deviations from the desired temperature have increased · it might become necessary to operate at a higher temperature, significant impact for the FI CCDs

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
2. E0102: Gratuitous Pretty Pictures of E0102
S3 Summed Data ~100 ks

CXC

RGS Spectrum (Pollock 2006)

Objective: develop a spectral model which can be used by RGS, HETG, EPIC & ACIS, etc.
Paul Plucinsky 10

EPIC Cal April 2007


Chandra X-Ray Observatory
Application of RGS Spectral Model
Dewey (MIT)

CXC

Use RGS spectral model Construct a spatial model Compare simulation to d a ta Bright lines agree well

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
MEG minus 1st order

CXC

MgXI
Simulation

NeX NeIX

OVIII

OVII

Comparison

KS test

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
MEG plus 1st order

CXC

MgXI
Simulation

NeX NeIX

OVIII

OVII

Comparison

KS test

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Joint Fit with Pollock Model to ACIS S3, MOS1/2 & pn

CXC

SAS 7.0, latest CCF Many thanks Steve !! No fit, adopt Pollock RGS model Brems kT = 0.36 keV CCD spectra prefer a harder continuum

NH=5.36e20 Line Es and widths frozen, Norms free

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Joint Fit with Pollock Model to ACIS S3, MOS1/2 & pn

CXC

Fit, Brems kT =0.60 keV NH=5.36e20 Line Es & widths frozen, norms free

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Individual Fit with Pollock Model to ACIS S3

CXC

Fit, Brems kT =0.60 keV NH=5.36e20 Line Es & widths frozen, norms free

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Individual Fit with Pollock Model to MOS1

CXC

Fit, Brems kT =0.60 keV NH=5.36e20 Line Es & widths frozen, norms free

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory

CXC

Individual Fit with Pollock Model to MOS1: Ne lines free
Fit, Brems kT =0.65 keV NH=5.36e20 Ne Line Es free, widths frozen, norms free

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Individual Fit with Pollock Model to pn

CXC

Fit, Brems kT =0.40 keV NH=5.36e20 Line Es frozen, widths frozen, norms free

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Where Do We Go From Here ?

CXC

· Dewey analysis needs to be updated with latest response files for
HRMA/ACIS/HETG · Line-based analysis needs to be updated with the latest response files for HRMA/HETG/ACIS · RGS data need to be re-analyzed with new background model for RGS · RGS and HETG teams agree on a model well before the IACHEC meeting in California · ACIS, MOS, and pn use the new model to fit the CCD spectra

Paul Plucinsky

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EPIC Cal April 2007


Chandra X-Ray Observatory
Let's Agree on a Model !!!!!!!
Purpose: to improve the low-energy response model of ACIS, MOS and pn CCD instruments

CXC

1 2 3 4 5 6

) ) ) ) ) )

RGS and HETG agree on flux of bright lines RGS and HETG compromise on existence of weak lines RGS and HETG agree on widths for the lines Select a continuum model and absorption HETG team must analyze second epoch observations of E0102 Fit ACIS, MOS, and pn with the same model

Paul Plucinsky

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EPIC Cal April 2007