Hi Ruta,

Did you recalibrate the jump?  It is not clear from your message.  After a cleaning we usually refocus the plates and commonly do a new mass calibration at the same time.  The condition of your source will be in a new state, so an electrical tune up also may be in order.

Good luck, Ben

 
Benjamin Harlow
Manager, Stable Isotope Core Laboratory
Washington State University
School of Biological Sciences
367 Eastlick
Pullman, WA  99164-4236
 
Office:  509-335-6161
Lab:     509-335-6154
Fax:     509-335-3184
 
Laboratory for Biotechnology and Bioanalysis (LBB2) Stable Isotope Core
http://www.isotopes.wsu.edu
 
 

-----Original Message-----
From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Ruta Bariseviciute
Sent: Wednesday, September 18, 2013 2:50 AM
To: [log in to unmask]
Subject: [ISOGEOCHEM] Jum Calibration problems in IRMS

Dear colleges,
We have Delta V Advantage IRMS. We have cleaned the ion source. After cleaning we have problems with Jump calibration (N2 to CO2). Separate N2 and CO2 measurements are good. Has anybody had such a problem? It appeared just after ion source cleaning.