Detector noise & Vela observations

VILSPA/Spain, 2004 March 23-24Detector noise & Vela observationsEPIC Calibration Meeting, K. Dennerl

Detector noise & Vela observations

application to Vela observations

EPIC pn detector noise suppressionand


adu

Quadrant 0

50.7 ks closed FF (rev 059)

EPIC-pn detector noise


EPIC-pn detector noise (FF)

PHA < 50 adu (~250 eV)

PHA > 50 adu (~250 eV)

0 80 0 4


Detector noise in FF and eFF mode

closed eFF exposure, rev 537, 16.3 ks, 20-30 adu

original image .. after spatial offset correction



closed FF exposure, rev 532, 21.0 ks, 20-30 adu


scaled to eFF exp [ks]



closed FF exposure, rev 532, 21.0 ks, 20-30 adu


scaled to eFF exp [ks]

scaled to eFF frame

number



closed eFF exposure, rev 537, 16.3 ks, 20-30 adu



2.16 : 12.16 : 1


FF

eFF

detector noise per per secsec is ~2.16 times

higher in FF than in eFF

[adu]


EPIC-pn detector noise properties (FF)


raw_y

20-65 adu

nois

e



SAS CCF:



reference image for the 20 adu intensities per pixel, normalized to 1 ks

obtained by accumulating images at 20 adu from long FF exposures with no bright X-ray source in the field, and computing the median value for each pixel

20 adu reference image for FF

SAS CCF:


closed FF rev 462 23.2 ks

original 20 adu image


patches identified in the original 20 adu image







original 20 adu image, after offset shift correction

(scale: 0 – 50)



original 20 adu image, after offset shift correction and noise suppression

(scale: 0 – 3)


closed FF revs 129 - 532






















Detector noise & Vela observations

application to Vela observations

EPIC pn detector noise suppressionand


Previous Vela observations (FF)

Rev Duration

Date RA Dec PA

367 33.9 ks 10.12.2001

08:48:55.7 -45:38:07 132.7

448 58.5 ks 21.05.2002

08:48:55.7 -45:41:33 294.9

533 31.2 ks 06.11.2002

08:48:48.8 -45:38:29 101.0

534 38.8 ks 08.11.2002

08:48:49.1 -45:38:26 102.8


Vela SNR FF rev 367

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 448

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 533

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 534

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 718a

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 718b

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 740

E = 0.25 – 1.0 keV

E > 10 keV


Vela SNR FF rev 367



Vela SNR FF rev 367

areas with negative offset shifts applied


Vela SNR FF rev 367



Vela SNR FF rev 367

areas with positive offset shifts applied


Vela SNR FF rev 367



Vela SNR FF rev 367

original 20 adu image, after offset shift correction

(scale: 0 – 50)


Vela SNR FF rev 367

default epreject

parameters


(scale: 0 – 5)


Vela SNR FF rev 367

epreject noise

parameters adjusted


(scale: 0 – 5)


Vela SNR FF rev 367 33.9 ks

20 adu images after eprejectdefault noiseparameters

adjusted




adjusted


Vela SNR FF rev 718a 40.7 ks


adjusted


Vela SNR FF rev 718b 36.7 ks


adjusted




adjusted




adjusted


Vela SNR FF rev 367 120-200 eV

PHA > 20 and 120 < PI <

200

scale: 0-40

without epreject


PHA > 20 and 120 < PI <

200

scale: 0-20

with epreject

Vela SNR FF rev 367 120-200 eV



without epreject



with epreject



without/with epreject



without epreject



with epreject



without/with epreject

with

without

withoutwith



450 – 700 eV sky coordinates

















Vela SNR FF rev 740a (18.3 ks)



Vela SNR FF rev 740b (29.4 ks)



Vela SNR FF rev 367 (33.9 ks)

450-700 eV

detector coordinates

scale: 0 - 15



450-700 eV


scale: 0 - 15



450-700 eV


scale: 0 - 15



450-700 eV


scale: 0 - 15



450-700 eV


scale: 0 - 15



450-700 eV


scale: 0 - 15



450-700 eV


scale: 0 - 15



450-700 eV


scale: 0 - 15


Vela SNR FF revs 367 - 740b

450-700 eV


scale: 0 - 15



450-700 eV


exposure map





preliminary



preliminary


Printed circuit board


Vela SNR FF O-K revs 367-534

Documents

Detector noise & Vela observations