Документ взят из кэша поисковой машины. Адрес оригинального документа : http://xmm.vilspa.esa.es/sas/5.4.1/doc/emevents/node4.html
Дата изменения: Fri Jan 10 22:52:58 2003
Дата индексирования: Sat Dec 22 09:04:23 2007
Кодировка:
Поисковые слова: п п п п п п п п

XMM-Newton Science Analysis System


emevents (emevents-6.5.4) [xmmsas_20030110_1802-5.4.1]

Meta Index / Home Page / Description

Patterns

Figure 1: List of EPIC-MOS patterns (IMAGING mode)

The figure should be interpreted as follows:

• each pattern is included in a 5x5 matrix used for proximity analysis.
• a pattern is centered by definition on the pixel with highest charge.
• this central pixel is colored in red (its charge is E$_1$).
• the other pixels above threshold in the pattern are colored in green (the sum of their charges is E$_2$).
• all pixels colored in white must be below threshold.
• the crossed pixels are indifferent (they can be above threshold).
• the patterns are recognized in increasing order (this is important only for pattern 30, which comprises patterns 0 and 26-29).

The philosophy for patterns 0-25 is that a good X-ray pattern must be compact, with the highest charge at the center, and isolated (all pixels around are below threshold).

Patterns 26-29 are the so-called diagonal patterns, not expected from a genuine X-ray, but which can arise in case of Si fluorescence or of pileup of two monopixel events.

The E$_3$ and E$_4$ data in the ODF event lists have nothing to do with the "white" and "crossed" pixels.

• E$_3$ is the sum of charges of pixels below threshold in the 8 pixels of the 3x3 corona (their number is known from the pattern number).
• E$_4$ is the sum of charges of pixels below threshold in the 16 pixels of the 5x5 corona. Their number N4 is known from the PERIPIX column in the event list, which stores the number of pixels above threshold in the 5x5 corona. Thus N4 = 16 - PERIPIX.