From hwarren@cfa.harvard.edu Tue Nov 18 16:42:57 2003
Date: Wed, 05 Aug 1998 13:21:37 -0400
From: Harry Warren <hwarren@cfa.harvard.edu>
Reply-To: sumer-soft@esa.nascom.nasa.gov
To: sumer-soft@esa.nascom.nasa.gov
Subject: Re: SUMER-SOFT: SUMER statistics

Dear Elena,

As I understand it, SUMER's detectors are micro-channel plates with
cross delay line electrons (i.e., photon counting) so that the
statistical errors are predominately poisson (counting statistics). I'm
sure you'll get a better answer from someone on the SUMER team though.

Harry Warren

Elena Perez wrote:
> 
> Hello,
> 
> I'm trying to calculate errors from SUMER data, and I wonder whether anyone
> can help me. I've been looking at the SUMER www page and Wilhelm et al.,97,
> but it's not obvious to me what the sources of potential error are. In CDS
> (NIS) data photon statistics, detector noise (readout noise + bias) and pixel
> cross-talk are important. (see CDS Software Note No. 49)
> What kind of errors have to be considered for SUMER?
> 
> >From Wilhelm et al.'97 I understood that background noise and bias errors
> were very small, almost negligible. Is this right? I haven't found anything
> about readout noise... On the other hand, in the photon statistics for CDS
> what is called "the pulse height distribution" (PHD) is important.
> Is this also important for SUMER?
> 
> Thanks in advance for any help.
> 
> Regards,
> 
> Elena Perez

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