Change request #749
Move instrument, ontime, livetime and deadc attributes to GObservation base class
| Status: | New | Start date: | 02/06/2013 | |
|---|---|---|---|---|
| Priority: | Normal | Due date: | ||
| Assigned To: | - | % Done: | 0% | |
| Category: | - | |||
| Target version: | - | |||
| Duration: |
Description
- instrument name
- ontime
- livetime
- deadtime correction factor
It is therefore reasonable to move these attributes in the base class and to add methods for setting and retrieving these attributes. They can then be removed from the instrument specific observation classes.
Recurrence
No recurrence.
History
#1
Updated by Deil Christoph over 10 years ago
While doing this, would it be possible to clarify what deadc is (and maybe choose a more explicit name)?
Is it a time? Or a correction factor?
In HESS we call this the “deadtime correction factor”:
t_live = t_obs * (1 - deadtime_correction_factor)
and this the “deadtime”:
t_dead = deadtime_correction_factor * t_obs
In GCTAObservation I see deadc twice:
virtual double deadc(const GTime& time) const;
void deadc(const double& deadc);
So deadc is used as “deadtime correction factor” and “deadtime” in different places?
#2
Updated by Knödlseder Jürgen over 10 years ago
Deil Christoph wrote:
While doing this, would it be possible to clarify what
deadcis (and maybe choose a more explicit name)?
deadc is the OGIP name, and indeed, it’s the deadtime correction factor.
Is it a time? Or a correction factor?
In HESS we call this the “deadtime correction factor”:
t_live = t_obs * (1 - deadtime_correction_factor)
and this the “deadtime”:
t_dead = deadtime_correction_factor * t_obs
It’s exactly this.
In
GCTAObservationI seedeadctwice:
[...]So
deadcis used as “deadtime correction factor” and “deadtime” in different places?
The first method is to retrieve the value as function of time, the second is to set it as a constant. This is not very consistent, but only the first is imposed by the interface (i.e. in general, deadc may be time dependent) while the second is CTA specific, where deadc is a constant for a given observation (deadc is actually a keyword in Karl’s event list format).