XMM EPIC MOS Steve Sembay Mallorca 26/10/06 MOS spectral redistribution function has evolved temporarily and spatially whilst in orbit. We do not have an accurate physical description of the effect which can be used to model the observed changes. Problem #1 Observations of astronomical objects with known spectral parameters can be used analytically to adjust the parameters of the rmf for all detector/epoch/region/pattern combinations. Solution #1 Problem #2 Extremely time consuming as this is largely a manual process requiring analysis of potentially hundreds of spectral fits to fully characterise the rmf evolution. Automated Spectral Response Fitting Solution #2

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 function myfunct, p ; p(n) newccf = rmf_param_adjust(p, oldccf) rmf = rmfgen(newccf) chisq = xspec_fit(spectrum, model, rmf) return, chisq end pro rmfmin, p, chimin result = tnmin(‘myfunct’, p, bestmin=chimin, /autoderivative) newccf = rmf_param_adjust(result, oldccf) return end E = 1.49 keV model ga σ = 0.0 N = free σ new (1.49) = p x σ old (1.49) Code development by Jenny

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 ;+ ; NAME: ; TNMIN ; ; AUTHOR: ; Craig B. Markwardt, NASA/GSFC Code 662, Greenbelt, MD ; ; UPDATED VERSIONs can be found on my WEB PAGE: ; ; ; PURPOSE: ; Performs function minimization (Truncated-Newton Method) ; ; MAJOR TOPICS: ; Optimization and Minimization ; ; CALLING SEQUENCE: ; parms = TNMIN(MYFUNCT, X, FUNCTARGS=fcnargs, NFEV=nfev, ; MAXITER=maxiter, ERRMSG=errmsg, NPRINT=nprint, ; QUIET=quiet, XTOL=xtol, STATUS=status, ; FGUESS=fguess, PARINFO=parinfo, BESTMIN=bestmin, ; ITERPROC=iterproc, ITERARGS=iterargs, niter=niter) ; ; DESCRIPTION: ; ; TNMIN uses the Truncated-Newton method to minimize an arbitrary IDL ; function with respect to a given set of free parameters. Blah…….

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 function myfunct, p ; p(n) newccf = rmf_param_adjust(p, oldccf) rmf = rmfgen(newccf) chisq = xspec_fit(spectrum, model, rmf) return, chisq end pro rmfmin, p, chimin result = tnmin(‘myfunct’, p, bestmin=chimin, /autoderivative) newccf = rmf_param_adjust(result, oldccf) return end Slow ~ secs to mins

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Results from 3 sets of tests: 1)Fitting the Al calibration line(s) at epoch Rev )Fitting the low energy continuum of 3C273 at epoch )Fitting the continuum of RXJ1856 at epoch 744+ Mono-pixel spectra used throughout

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #1: Resolution at Al K α

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #1: Resolution at Al K α “Red” wing is due to incomplete charge collection rather than intrinsic broadening Al Kα = K α1 (1.4867) x K α2 (1.4863) In our analytic rmf model we model this by splitting the profile “Red” side = Gaussian(σ) + Gaussian(R x σ) “Blue” side = Gaussian(σ) Normalisations match at join In our automatic fitting we adjust the values of σ (~30) and R (~1.5) at keV by “fudge” factors, p, such that σ new = p 1 x σ old R new = p 2 x R old

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 E = , σ = 0.0, N = 0.01N 0 Spectral Model: (ga + ga + ga)Fit Range: keV Test #1: Resolution at Al K α E = , σ = 0.0, N = 0.5N 0 E = , σ = 0.0, N 0 = free P 1 = 1.0 P 2 = 1.0 Χ 2 ν = 18.4 P 1 = P 2 = Χ 2 ν = 7.74 Proc. Time = 1.72 hrs α1α1 α2α2 β1β1

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #1: Resolution at Al K α MOS1 Mg XI line in Zeta Puppis, Rev 0156, RGS Model

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 MOS1 ratio image Energy Epoch TU Mode Test #2: Low energy continuum of 3C 273 (Rev 0094) Continuum (“hard power law + soft excess”) fits to 3c 273

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #2: Low energy continuum of 3C 273 (Rev 0094) f(d) d f(d) = α + βd d < d 0 = 1.0 d ≥ d 0 d0d0 α E obs (d) = E in (d) x f(d) Integrate over d to get profile α β Surface Loss Function

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #2: Low energy continuum of 3C 273 (Rev 0094) Alpha Parameter v Energy, Epoch Rev Fudge factor defined at 350, 500, 650 eV

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #2: Low energy continuum of 3C 273 (Rev 0094) nH = 1.79 x cm -2 Γ = 1.644, N 0 = Γ = Free, N 0 = Free Spectral Model: phabs * (po + po)Fit Range: keV Rev 0094 Χ 2 ν = 3.01 Χ 2 ν = 1.97 Proc. Time: 3.9 Hrs

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #2: Low energy continuum of 3C 273 (Rev 0094) Alpha Parameter v Energy, Epoch Rev Fudge factor defined at 350, 500, 650 eV

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Fit model to PN and fold through MOS1 (old and new rmf) Test #2: Low energy continuum of 3C 273 (Rev 0094)

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 RGS model (renormalised) fit to MOS1 in keV band Test #2: Low energy continuum of 3C 273 (Rev 0094)

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) MOS1 Core nH = 1.4(0.1)E20 kT = 61.4(0.2) eV MOS1 Wings nH = 1.1(0.2)E20 kT = 60.3(0.4) eV

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) MOS2 Core nH = 0.93(0.1)E20 kT = 62.0(0.3) eV MOS2 Wings nH = 0.98(0.2)E20 kT = 59.7(0.5) eV

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) nH = 0.75 x cm -2 kT = 62 eV, N 0 = Free Spectral Model: phabs * bbFit Range: keV Fudge Factors: alpha surface loss parameters at…..250, 350, 450, 550 eV Parameters reported by Vadim/Frank for pn at previous Cal. meeting

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798)

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) Fit to MOS1 data with new rmf

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) Fit to MOS2 data with new rmf

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) Fit to MOS1 3c 273 data with old/new rmf nH = 2.6(0.2)e20 cm -2 nH = 2.1(0.2)e20 cm -2

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #3: BB fits to RXJ1856 (Rev 0798) Fit to MOS2 3c 273 data with old/new rmf nH = 2.4(0.2)e20 cm -2 nH = 1.9(0.2)e20 cm -2

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Conclusions Algorithm works! Timely results can be gained even using a single CPU, but we intend to port code to the multi(250) processor central computing facility at Leicester Smoothing out the residuals in early MOS 3c 273 data improves cross-calibration with pn and probably rgs Forcing spectral agreement between MOS and pn in RXJ1856 improves residuals in contemporary MOS2 3c 273 data

XMM EPIC MOS Steve Sembay Mallorca 26/10/06 Test #2: Low energy continuum of 3C 273