Up to top level
AO15   AO16   AO17   AO18   AO19   Backgrounds   Calibration   Conference   Data   Docs   EPICMOS   EPICpn   Feedback   Gallery   Misc   OM   Pending   PhD_Theses   Publications   RGS   RadMonitor   SAS_Hardware   SAS_WS   SASv16.0   SASv16.0_Installation   SASv16.1   SASv16.1_Installation   SASv17.0   SASv17.0_Installation   SASv18.0   SASv18.0_Installation   SciSim   Simulators_other   Suggestions   Trash   Visibility   XMM-bouncing   XMM-news   XRPS   XSA   esas   incoming  

Logged in as guest

Viewing Backgrounds/19184
Full headers

From: Hermine Landt <hlandt@head.cfa.harvard.edu>
Subject: subtract background
Compose reply
Download message
Move To:
2 replies: 1 2
1 followups: 1

Private message: yes  no

Notes:

Notification:


Date: Tue, 23 Aug 2005 14:37:47 -0400 (EDT)
From: Hermine Landt <hlandt@head.cfa.harvard.edu>
Subject: subtract background
To: xmmhelp@xmm.vilspa.esa.es
 hi,

is there an option in SAS to subtract the background from the spectrum,
and so to obtain a background subtracted spectral file for variability
studies?

    thanks,   Hermine




 ----------------------------------------------------------------
   Hermine Landt
   Harvard-Smithsonian           E-mail: hlandt@cfa.harvard.edu
     Center for Astrophysics     Phone:  +1-617-496-7824
   60 Garden Street, MS-70       Fax:    +1-617-495-7356
   Cambridge, MA 02138, USA

                http://hea-www.harvard.edu/~hlandt/
 ----------------------------------------------------------------


Reply 1

Resend
From: Matteo Guainazzi <xmmhelp@xmm.vilspa.esa.es>
To: hlandt@head.cfa.harvard.edu
Subject: Re: subtract background (PR#19184)
Date: Wed Aug 24 06:53:38 2005
Dear Hermine,

 it depends which instrument your are referring to. For RGS, it is enough to
properly define the parameter "bkgcorrect" in "rgsproc" (cf.
http://xmm.vilspa.esa.es/sas/6.5.0/doc/rgsproc/node25.html). For the EPIC
camera, there is no option in SAS to directly produce background-subtracted
spectra. However, one can safely use standard FTOOLS (such as "mathpha") to
generate them, as XMM-Newton spectra adhere to the OGIP standards.

 Regards,

 Matteo Guainazzi
 XMM-Newton Science Operations Center
 User Support Group


Followup 1

Compose reply
Download message
Date: Wed, 24 Aug 2005 10:36:17 -0400 (EDT)
From: Hermine Landt <hlandt@head.cfa.harvard.edu>
Subject: Re: subtract background (PR#19184)
To: Matteo Guainazzi <xmmhelp@xmm.vilspa.esa.es>
 hi Matteo,

it seems that the task "lccorr" does the job I need, i.e., to obtain a
background subtracted lightcurve. However, I cannot get it to work on my
EPIC datasets (lightcurves counts vs. time). I get the error message:

** lccorr: error (attributableNotFound) Could not find attribute with
qualified name temp_output_ts.ds:RATE%TIMEZERO in attributable set RATE


  thank you for your help,

    Hermine




 ----------------------------------------------------------------
   Hermine Landt
   Harvard-Smithsonian           E-mail: hlandt@cfa.harvard.edu
     Center for Astrophysics     Phone:  +1-617-496-7824
   60 Garden Street, MS-70       Fax:    +1-617-495-7356
   Cambridge, MA 02138, USA

                http://hea-www.harvard.edu/~hlandt/
 ----------------------------------------------------------------

On Wed, 24 Aug 2005, Matteo Guainazzi wrote:

> Dear Hermine,
>
>  it depends which instrument your are referring to. For RGS, it is enough
to
> properly define the parameter "bkgcorrect" in "rgsproc" (cf.
> http://xmm.vilspa.esa.es/sas/6.5.0/doc/rgsproc/node25.html). For the EPIC
> camera, there is no option in SAS to directly produce background-subtracted
> spectra. However, one can safely use standard FTOOLS (such as "mathpha") to
> generate them, as XMM-Newton spectra adhere to the OGIP standards.
>
>  Regards,
>
>  Matteo Guainazzi
>  XMM-Newton Science Operations Center
>  User Support Group
>



Reply 2

Resend
From: Matteo Guainazzi <xmmhelp@xmm.vilspa.esa.es>
To: hlandt@head.cfa.harvard.edu
Subject: Re: subtract background (PR#19184)
Date: Wed Aug 24 14:46:57 2005
Dear Hermine,

 it seems that you are running an old version of SAS, aren't you?

 Anyway, it does not matter. "lccorr" has been momentarily removed from the SAS
distribution (http://xmm.vilspa.esa.es/sas/new/documentation/releasenotes/xmmsas_6.5.0.shtml),
due to a few bugs affecting it, which have bee recently discovered. I recommend
you to use the FTOOLS "lcmath" instead (which does basically the same thing).

 Regards, Matteo

Up to top level
AO15   AO16   AO17   AO18   AO19   Backgrounds   Calibration   Conference   Data   Docs   EPICMOS   EPICpn   Feedback   Gallery   Misc   OM   Pending   PhD_Theses   Publications   RGS   RadMonitor   SAS_Hardware   SAS_WS   SASv16.0   SASv16.0_Installation   SASv16.1   SASv16.1_Installation   SASv17.0   SASv17.0_Installation   SASv18.0   SASv18.0_Installation   SciSim   Simulators_other   Suggestions   Trash   Visibility   XMM-bouncing   XMM-news   XRPS   XSA   esas   incoming  

Logged in as guest


Please make your (short) question the subject of your request!


Web interface using JitterBug ... back to the XMM home page