Chandra X-Ray Observatory CXC Paul Plucinsky EPIC Cal April 2007 1 1.ACIS Calibration: Recent Updates, Planned Updates, & Future Issues 2.E0102: Joint

Chandra X-Ray Observatory CXC

Paul Plucinsky EPIC Cal April 20071

1.1. ACIS Calibration: Recent Updates, ACIS Calibration: Recent Updates, Planned Updates, & Future IssuesPlanned Updates, & Future Issues

2.2. E0102: Joint Fits with ACIS S3, E0102: Joint Fits with ACIS S3, MOS1/2 & pnMOS1/2 & pn

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



1. Recent Updates to the ACIS Calibration 1. Recent Updates to the ACIS Calibration

• 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

CALDB 3.3.0 released on 15 December 2006



Planned Update: CTI Correction for Graded Mode for FI CCDsPlanned 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

Mn-K flight grade 8 (left split) for S2Bottom 256 rows Top 256 rows

Vikhlinin (SAO)



Map of Good and Bad Grades Map of Good and Bad Grades

Vikhlinin (SAO)

33 of 256 flightgrades are included in the ASCAG02346 grades

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



Comparison of Graded Mode and Faint Mode CTI CorrectionComparison of Graded Mode and Faint Mode CTI Correction

Posson-Brown

(SAO)

Graded modeCTI correctionprovides mostof the benefitof the Faintmode correction

For FI CCDs only !



Continuous Clocking Mode Calibration Continuous Clocking Mode Calibration

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

External Calibration Source: No CTI correction applied



Update on Contaminant BuildupUpdate on Contaminant Buildup

Data:Grant (MIT)

Model:O’Dell &Tennant(MSFC)



Optical Depth ComparisonOptical Depth Comparison

C-K Marshall (MIT)inferred optical depth at 700 eV

ECS Grant (MIT)Mn L

E0102 DePasquale (SAO) OVIII Ly-a



Future Issues: Focal Plane Operating TemperatureFuture Issues: Focal Plane Operating Temperature • 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



2. E0102: Gratuitous Pretty Pictures of E0102 2. E0102: Gratuitous Pretty Pictures of E0102

S3 Summed Data ~100 ksS3 Summed Data ~100 ks RGS Spectrum (Pollock 2006)RGS Spectrum (Pollock 2006)

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



Application of RGS Spectral ModelApplication of RGS Spectral Model Dewey (MIT)

Use RGS spectral model

Construct a spatial model

Compare simulation to data

Bright lines agree well



MEG minus 1st order

Simulation

Comparison

KS test

OVIII OVIINeIXNeXMgXI



MEG plus1st order

Simulation

Comparison

KS test

MgXI NeX NeIX OVIII OVII



Joint Fit with Pollock Model to ACIS S3, MOS1/2 & pnJoint Fit with Pollock Model to ACIS S3, MOS1/2 & pn

SAS 7.0, latest CCFMany thanksSteve !!No fit, adopt Pollock RGS modelBrems kT = 0.36 keVCCD spectra prefera harder continuumNH=5.36e20Line Es and widths frozen,Norms free



Joint Fit with Pollock Model to ACIS S3, MOS1/2 & pnJoint Fit with Pollock Model to ACIS S3, MOS1/2 & pn

Fit, Brems kT =0.60 keVNH=5.36e20Line Es & widths frozen, norms free



Individual Fit with Pollock Model to ACIS S3Individual Fit with Pollock Model to ACIS S3




Individual Fit with Pollock Model to MOS1Individual Fit with Pollock Model to MOS1




Individual Fit with Pollock Model to MOS1: Ne lines freeIndividual Fit with Pollock Model to MOS1: Ne lines free

Fit, Brems kT =0.65 keVNH=5.36e20Ne Line Es free, widths frozen, norms free



Individual Fit with Pollock Model to pnIndividual Fit with Pollock Model to pn

Fit, Brems kT =0.40 keVNH=5.36e20Line Es frozen, widths frozen, norms free



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

1) RGS and HETG agree on flux of bright lines2) RGS and HETG compromise on existence of weak lines3) RGS and HETG agree on widths for the lines4) Select a continuum model and absorption5) HETG team must analyze second epoch observations of E01026) Fit ACIS, MOS, and pn with the same model

Documents

Chandra X-Ray Observatory CXC Paul Plucinsky EPIC Cal April 2007 1 1.ACIS Calibration: Recent Updates, Planned Updates, & Future Issues 2.E0102: Joint