EPIC-pn background in deep fields – taking a deep breath

before diving

Finoguenov Alexis

HDFS

LH

COSMOSCOSMOS

COSMOS 9.5-12 keV

0.5-2 keV

COSMOS Andy Read

2-4.5 keV

COSMOS Andy Read

OOTE

Singles vs doubles

Spectral Spectral comparicompari

sonson

After Renormalization

Clean Andy

Detector Outskirts: the golden Mile

.. and renormalized

The effect of OOTE

Is there some sky background Is there some sky background in there?in there?

A msg from Andy Fabian

Strategy for background Strategy for background subtractionsubtraction

• Observation is filtered for flaresObservation is filtered for flares• We use the Filter wheel closed accumulation of We use the Filter wheel closed accumulation of

Michael Freyberg for pnMichael Freyberg for pn• The above is similar to De Luca & MolendiThe above is similar to De Luca & Molendi• We remove the sources identified by both We remove the sources identified by both

Chandra and XMM (5-10% residual Chandra and XMM (5-10% residual contamination)contamination)

• Two regions are used to test the in-field Two regions are used to test the in-field backgroundbackground

Components of the residual Components of the residual spectrumspectrum

• Hard X-ray background: 0.9-1.0 slopeHard X-ray background: 0.9-1.0 slope

• Galactic emission of 0.1 and 0.2 keVGalactic emission of 0.1 and 0.2 keV

• Intrumental background: quiescent soft Intrumental background: quiescent soft protonsprotons

background slope 3background slope 3

Flux is similar to total CXBFlux is similar to total CXB

ConclusionsConclusions

• Background in deep fields appears to be similarBackground in deep fields appears to be similar• Initial problems with use of Andy Read‘s or Initial problems with use of Andy Read‘s or

David Lumb‘s background seems to resolve in David Lumb‘s background seems to resolve in difference in the cleaningdifference in the cleaning

• A consistent answer to 2-10 keV Cosmoc A consistent answer to 2-10 keV Cosmoc background with De Luca&Molendibackground with De Luca&Molendi

• Quiescent soft proton flux is not evolving Quiescent soft proton flux is not evolving during 2002-2004during 2002-2004