Is it possible in Athena to change the y-axis (energy scale) at two different energy points of an EXAFS scan? I have a Ni foil spectrum as a function of time. The edge can be set at 8333.0 eV, and I want to to assign higher energy to a known feature in the Ni scan. Syed Khalid 725D, National Synchrotron Light Source Brookhaven National Laboratory Upton, NY 11973 Ph: 631-344-7496 FAX: 631-344-3238 e-mail: khalid@bnl.gov
On Monday 08 September 2008 12:20:47 Khalid, Syed wrote:
Is it possible in Athena to change the y-axis (energy scale) at two different energy points of an EXAFS scan?
I have a Ni foil spectrum as a function of time. The edge can be set at 8333.0 eV, and I want to to assign higher energy to a known feature in the Ni scan.
I am not 100% certain I understand the question, but I think the question is about the calibration dialog. That is, you want to assign an energy shift, but not referenced to the edge energy position. Why can't you just set the energy shift by hand on Athena's main page? B -- Bruce Ravel ------------------------------------ bravel@bnl.gov National Institute of Standards and Technology Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2 Building 535A Upton NY, 11973 My homepage: http://xafs.org/BruceRavel EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/
Khalid, what you can do is to note how much the higher energy (at energy E1) feature is shifted from what you think it should be (let's say by the amount of D eV), provided that you fixed the lower energy point to what you wanted (say, E0). Then, you should transfer the data into a spreadsheet and apply linear scaling: E --> E0 + (E-E0)*D It will ensure that in the range between E0 and E1 the data are linearly stretched or compressed, depending on the sign of D. Anatoly = _____ From: Khalid, Syed [mailto:khalid@bnl.gov] Sent: Monday, September 08, 2008 12:21 PM To: ifeffit@millenia.cars.aps.anl.gov Subject: [Ifeffit] enrgy-axis-expansion Is it possible in Athena to change the y-axis (energy scale) at two different energy points of an EXAFS scan? I have a Ni foil spectrum as a function of time. The edge can be set at 8333.0 eV, and I want to to assign higher energy to a known feature in the Ni scan. Syed Khalid 725D, National Synchrotron Light Source Brookhaven National Laboratory Upton, NY 11973 Ph: 631-344-7496 FAX: 631-344-3238 e-mail: khalid@bnl.gov _______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
On Monday 08 September 2008 14:03:05 Carlo Segre wrote:
It sounds to me like the question is a bit more complex than that. I believe that with their continuous scan electronics, they get absorption as a function of time, not energy. If I am not mistaken, he is asking to have a conversion to energy built in somehow.
From this, I finally understand the question.
Athena does not currently provide a mechanism for expanding the energy axis. I could be convinced to code that up, but I would need a clearer statement of what you actually want done and several clear examples of how to process the data correctly. B On Monday 08 September 2008 13:59:42 Anatoly Frenkel wrote:
Khalid, what you can do is to note how much the higher energy (at energy E1) feature is shifted from what you think it should be (let's say by the amount of D eV), provided that you fixed the lower energy point to what you wanted (say, E0). Then, you should transfer the data into a spreadsheet and apply linear scaling:
E --> E0 + (E-E0)*D
It will ensure that in the range between E0 and E1 the data are linearly stretched or compressed, depending on the sign of D.
Anatoly
=
_____
From: Khalid, Syed [mailto:khalid@bnl.gov] Sent: Monday, September 08, 2008 12:21 PM To: ifeffit@millenia.cars.aps.anl.gov Subject: [Ifeffit] enrgy-axis-expansion
Is it possible in Athena to change the y-axis (energy scale) at two different energy points of an EXAFS scan?
I have a Ni foil spectrum as a function of time. The edge can be set at 8333.0 eV, and I want to to assign higher energy to a known feature in the Ni scan.
Syed Khalid 725D, National Synchrotron Light Source Brookhaven National Laboratory Upton, NY 11973
Ph: 631-344-7496 FAX: 631-344-3238 e-mail: khalid@bnl.gov
_______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
-- Bruce Ravel ------------------------------------ bravel@bnl.gov National Institute of Standards and Technology Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2 Building 535A Upton NY, 11973 My homepage: http://xafs.org/BruceRavel EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/
I do not clearly understood what you mean. could you explain it more precisely? do you want to replace the x scale from energy to time? if you want only set the edge energy use E0 kicaj ________________________________ Od: ifeffit-bounces@millenia.cars.aps.anl.gov w imieniu Khalid, Syed Wysłano: Pn 2008-09-08 18:20 Do: ifeffit@millenia.cars.aps.anl.gov Temat: [Ifeffit] enrgy-axis-expansion Is it possible in Athena to change the y-axis (energy scale) at two different energy points of an EXAFS scan? I have a Ni foil spectrum as a function of time. The edge can be set at 8333.0 eV, and I want to to assign higher energy to a known feature in the Ni scan. Syed Khalid 725D, National Synchrotron Light Source Brookhaven National Laboratory Upton, NY 11973 Ph: 631-344-7496 FAX: 631-344-3238 e-mail: khalid@bnl.gov _______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
On Monday 08 September 2008 16:40:47 Zajac, Dariusz wrote:
I do not clearly understood what you mean. could you explain it more precisely? do you want to replace the x scale from energy to time? if you want only set the edge energy use E0
Apparently (and Khalid or Anatoly should correct me if I am wrong), they are collecting data as a function of time in quick scan mode. They then have the problem of converting time to energy. If the mono speed is recorded somehow incorrectly, then there is an accordian effect throughout the data. I think that Khalid wants to be able to adjust this accordian effect to correct the energy scale of teh data. B -- Bruce Ravel ------------------------------------ bravel@bnl.gov National Institute of Standards and Technology Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2 Building 535A Upton NY, 11973 My homepage: http://xafs.org/BruceRavel EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/
Hi Khalid, I agree with Dariusz: I do not understand the question. I have a hard time believing it is "the beamline cannot provide data as a function of energy, can Athena do this for me automatically?" (if it is, the answer is definitely 'No!'). Could you explain what you're trying to do? --Matt
hi so, I think, in case of converting time scale to energy - this should be supported by beamline (beamline scientist) somehow... if there is any nonlinearity of the converion factor (Anatoly - what whould happened if D parameter is time/energy dependent?) I think only reference spectra can help - do you have it Syed? if you have all needed parameters the calibration can be relatively quickly done in some other programs, also in macro (for many files) but that's my speculations kicaj
-----Original Message----- From: ifeffit-bounces@millenia.cars.aps.anl.gov [mailto:ifeffit-bounces@millenia.cars.aps.anl.gov] On Behalf Of Bruce Ravel Sent: Monday, September 08, 2008 10:59 PM To: XAFS Analysis using Ifeffit Subject: Re: [Ifeffit] ODP: enrgy-axis-expansion
On Monday 08 September 2008 16:40:47 Zajac, Dariusz wrote:
I do not clearly understood what you mean. could you explain it more precisely? do you want to replace the x scale from energy to time? if you want only set the edge energy use E0
Apparently (and Khalid or Anatoly should correct me if I am wrong), they are collecting data as a function of time in quick scan mode. They then have the problem of converting time to energy. If the mono speed is recorded somehow incorrectly, then there is an accordian effect throughout the data. I think that Khalid wants to be able to adjust this accordian effect to correct the energy scale of teh data.
B
-- Bruce Ravel ------------------------------------ bravel@bnl.gov
National Institute of Standards and Technology Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2 Building 535A Upton NY, 11973
My homepage: http://xafs.org/BruceRavel EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/
_______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
participants (5)
-
Anatoly Frenkel -
Bruce Ravel -
Khalid, Syed -
Matt Newville -
Zajac, Dariusz