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You are right Tim, the only argument I had is that it was proposed to have the current AND the scaling factor in conditions DB. In my mind there is no scaling factor. Stepan On 2/3/15 11:48 AM, Nelson, Timothy Knight wrote: > I think everyone is saying the same thing here, no? With that formula, the current IS the scaling factor. > > Tim > >> On Feb 3, 2015, at 8:40 AM, Stepan Stepanyan <[log in to unmask]> wrote: >> >> Hi Norman, >> >> OK, fine, so we do not need a scaling factor in conditions DB. >> What we will need in addition to my list is the parameters >> of functions B_field(G)=a+b*I(A), and I(A)=c+d*B_field(G), >> relation between current and central field. Here are parameters: >> a=-4.298 >> b=-6.506 >> c=-0.6657 >> d=-0.1537 >> >> Regards, Stepan >> >> >> On 2/3/15 10:02 AM, Graf, Norman A. wrote: >>> Hello Stepan, >>> For any particular analyzing dipole magnet setting, we would either use the >>> calculated field map at the next highest calculated point and scale it down, or >>> the next lower calculated point and scale it up. >>> >>> "Any scaling factor will depend on values of central fields of closest simulated >>> field maps and the value of the central field we run with." >>> Exactly. >>> >>> "So, where this independent scaling factor comes into play?" >>> There is no independent scaling factor. It is derived as you mentioned above. >>> >>> Norman >>> ________________________________________ >>> From: Stepan Stepanyan <[log in to unmask]> >>> Sent: Tuesday, February 3, 2015 3:42 AM >>> To: Graf, Norman A.; McCormick, Jeremy I.; Nathan Baltzell >>> Cc: hps-software >>> Subject: Re: Bfield conditions >>> >>> Hi Norman, >>> >>> Thanks for the explanations, but I m not sure I got it. >>> Yes, we have field maps at some discrete values of central >>> fields (or currents) and highly unlikely experiment will run >>> at any of the existing values. The experimental setting will >>> be in between some of two existing maps. Any scaling factor >>> will depend on values of central fields of closest simulated >>> field maps and the value of the central field we run with. >>> >>> So, where this independent scaling factor comes into play? >>> >>> Regards, Stepan >>> >>> On 2/2/15 11:22 PM, Graf, Norman A. wrote: >>>> Hello Stepan, >>>> You provided field maps calculated at discrete values of the central field. >>>> For simulation and reconstruction we will be using the field maps >>>> calculated for the nominal running field and apply an overall scaling >>>> factor to account for deviations in the analyzing dipole magnet current. >>>> Norman >>>> ________________________________________ >>>> From: Stepan Stepanyan <[log in to unmask]> >>>> Sent: Monday, February 2, 2015 7:15 PM >>>> To: McCormick, Jeremy I.; Graf, Norman A.; Nathan Baltzell >>>> Cc: hps-software >>>> Subject: Re: Bfield conditions >>>> >>>> Hello Jeremy, >>>> >>>> My list for magnet settings will be the following: >>>> - beam energy (since magnet setting depends on it) >>>> - analyzing magnet current as measure on power supply >>>> - analyzing field as measured in the homogenous region >>>> - frascati magnet current as measured on the power supply >>>> - frascati magnet field value as measured in the homogenous region >>>> Frascati setting is important since the beam direction on the target >>>> depends on it. >>>> All of these will be injected to data stream as part of EPICS as well as >>>> will be >>>> available through the slow control data base (MYA). >>>> >>>> Of course, in addition to the field values in homogenous region we >>>> should have the full field >>>> maps stored, available somewhere. We should define how we will scale >>>> field maps, e.g. >>>> take the closest available (in current or in central field value) and >>>> scale, or fit point by point. >>>> >>>> By the way, I am not sure what it means scaling factor, may be some one >>>> can explain me. >>>> >>>> Regards, Stepan >>>> >>>> >>>> On 2/2/15 8:55 PM, McCormick, Jeremy I. wrote: >>>>> Hi, Norman. >>>>> >>>>> Thanks for the information. >>>>> >>>>> I basically need to know what the database table(s) should look like.... >>>>> >>>>> e.g. >>>>> >>>>> What columns should it have? What are the units on those columns? >>>>> >>>>> The proposal on the JIRA item currently is.... >>>>> >>>>> field - the measured By (I think?) in Tesla, presumably of the analyzing dipole >>>>> >>>>> scale - scaling factor of the B-field for the run (all components) >>>>> >>>>> So is that enough for what we want to do with this information in recon/analysis? Or do we need more columns with additional information? >>>>> >>>>> If we need more columns, please tell me what they should be. >>>>> >>>>> Also, if there are different conditions measured at different times (multiple magnets?), then we can model them with other classes. >>>>> >>>>> Right now, I'd propose a generic "BfieldConditions" object but we aren't limited to having one type if more classes/tables are needed for this. >>>>> >>>>> Thanks. >>>>> >>>>> --Jeremy >>>>> >>>>> -----Original Message----- >>>>> From: Graf, Norman A. >>>>> Sent: Monday, February 02, 2015 5:47 PM >>>>> To: Nathan Baltzell; McCormick, Jeremy I. >>>>> Cc: hps-software >>>>> Subject: Re: Bfield conditions >>>>> >>>>> Jeremy, et al., >>>>> We will need to monitor the analyzing dipole current. I assume this is an EPICS variable, or should be. We will also be mounting a Hall probe onto the SVT support plate. This will give us a direct measure of the magnetic field strength. Deviations from nominal settings will give us the scaling factor to use for the simulation/reconstruction. I would use the magnet current as the primary and the Hall probe as check, but we can monitor both during early commissioning. >>>>> Norman >>>>> ________________________________________ >>>>> From: [log in to unmask] <[log in to unmask]> on behalf of Nathan Baltzell <[log in to unmask]> >>>>> Sent: Monday, February 2, 2015 5:24 PM >>>>> To: McCormick, Jeremy I. >>>>> Cc: hps-software >>>>> Subject: Re: Bfield conditions >>>>> >>>>> Hi Jeremy, >>>>> >>>>>> current - the beam current in amps >>>>> I think beam current is not related to chicane settings. >>>>> >>>>>> But I'm not sure where this information all comes from... >>>>> Empirical numbers are magnet currents, from which comes a scale factor relative to some defined nominal value. >>>>> >>>>>> current - Will this be in the data stream for the upcoming runs? Or >>>>>> should we access it through the MYA command line tool? (Obviously >>>>>> prefer into the data stream.) >>>>> We will be putting various EPICs variables, including chicane current readbacks, into EVIO every few seconds for the next run. How we will parse it needs to be written and tested. >>>>> >>>>> -Nathan >>>>> >>>>> >>>>> >>>>> On Feb 2, 2015, at 7:44 PM, "McCormick, Jeremy I." <[log in to unmask]> wrote: >>>>> >>>>>> -----Original Message----- >>>>>> From: McCormick, Jeremy I. >>>>>> Sent: Monday, February 02, 2015 4:43 PM >>>>>> To: 'Nathan Baltzell' >>>>>> Cc: Graham, Mathew Thomas; Graf, Norman A. >>>>>> Subject: RE: Bfield conditions >>>>>> >>>>>> Hi, Nathan. >>>>>> >>>>>> I'll CC a couple people who might be interested in this... >>>>>> >>>>>> It was requested that I add B-field information to the conditions system. >>>>>> >>>>>> https://jira.slac.stanford.edu/browse/HPSJAVA-312 >>>>>> >>>>>> So I was planning to just add a single table with... >>>>>> >>>>>> current - the beam current in amps >>>>>> >>>>>> field - measured field value in tesla or kG >>>>>> >>>>>> scale - scaling factor of field map for the run >>>>>> >>>>>> But I'm not sure where this information all comes from... >>>>>> >>>>>> current - Will this be in the data stream for the upcoming runs? Or >>>>>> should we access it through the MYA command line tool? (Obviously >>>>>> prefer into the data stream.) >>>>>> >>>>>> field - Field value at the IP or some other position? When is this measured? How do we get it automatically? Or do we just input this manually? >>>>>> >>>>>> scale - I don't know how we get this number. Is it derived from the current? If it is derived should we even store it separately or just compute on the fly? >>>>>> >>>>>> I can add the API regardless of whether we know how to get the information, but we should discuss how to access/load this information up front. >>>>>> >>>>>> Thanks. >>>>>> >>>>>> --Jeremy >>>>>> >>>>>> -----Original Message----- >>>>>> From: Nathan Baltzell [mailto:[log in to unmask]] >>>>>> Sent: Monday, February 02, 2015 4:33 PM >>>>>> To: McCormick, Jeremy I. >>>>>> Subject: Re: Bfield conditions >>>>>> >>>>>> Chicane setting relative to nominal is in data catalog, done manually from the spreadsheet this time. We also have magnet currents in epics. >>>>>> >>>>>> This will be something that will be in the jlab mysql run db next time (in progress ...). >>>>>> >>>>>> >>>>>> >>>>>> On Feb 2, 2015, at 7:23 PM, "McCormick, Jeremy I." <[log in to unmask]> wrote: >>>>>> >>>>>>> I might have missed this someplace.... >>>>>>> >>>>>>> Do we have any B-field conditions for the runs? >>>>>>> >>>>>>> Like current, scaling, etc. >>>>>> ###################################################################### >>>>>> ## >>>>>> Use REPLY-ALL to reply to list >>>>>> >>>>>> To unsubscribe from the HPS-SOFTWARE list, click the following link: >>>>>> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 >>>>> ######################################################################## >>>>> Use REPLY-ALL to reply to list >>>>> >>>>> To unsubscribe from the HPS-SOFTWARE list, click the following link: >>>>> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 >>>>> >>>>> ######################################################################## >>>>> Use REPLY-ALL to reply to list >>>>> >>>>> To unsubscribe from the HPS-SOFTWARE list, click the following link: >>>>> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 >>> ######################################################################## >>> Use REPLY-ALL to reply to list >>> >>> To unsubscribe from the HPS-SOFTWARE list, click the following link: >>> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 >> ######################################################################## >> Use REPLY-ALL to reply to list >> >> To unsubscribe from the HPS-SOFTWARE list, click the following link: >> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1 ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the HPS-SOFTWARE list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1