[Halld-cal] BCAL objects in DANA
Eugene Chudakov
gen at jlab.org
Fri Feb 12 09:55:55 EST 2010
An off topic comment on combining the photodetectors:
radial summing seems reasonable for the inner 6 layers
of the detectors, but is not obvious for the outer 4 layers.
I would try to combine the outer layers in groups 2x2.
It may happen that the shower will spread to fewer
readout channels.
We should simulate the energy resolution for these two options,
taking into account the noise in SiPMs.
Eugene
On Fri, 12 Feb 2010, Fernando J. Barbosa wrote:
> Hi Beni,
>
> The present plan is to get sums of three inner SiPMs and sums of four outer
> SiPMs, all radially. This is not fixed yet but budgets don't allow for finer
> granularity.
>
> Best regards,
> Fernando
>
>
>
> Beni Zihlmann wrote:
>> Hi All,
>> there is one more point to consider. Since we decided to go for SiPM we
>> also want to sum up signals from the SiPMs before
>> digitization. As a consequence there will be no direct relation between the
>> "True Hit" in a cell (single SiPM) from geant and
>> the digitization which has to be done after summing several SiPM first. I
>> am not sure if the exact number of SiPM that need
>> to be summed is already fixed or not.
>>
>> cheers,
>> Beni
>>
>> Hi David,
>>
>>> Sure there are "two levels" of truth information, I don't much see the
>>> point in having cell-level truth information though other than its one
>>> time use for doing digitization. Practically, if I want to know anything
>>> about resolution then I need the DBCALTruthShower, which *is* well named
>>> to correspond with DBCALShower. Comparing these two objects will tell me
>>> interesting things like my shower resolution and efficiency (this is why
>>> we have truth information for the user).
>>>
>>> I'm not sure what your suggestion is... if you want to get rid of HDDM in
>>> the name then simply renaming the class DHDDMBCALHit to DBCALTruthHit can
>>> be done. I think don't see any problem with the name and organization of
>>> the other classes though, with the exception that eventually the source of
>>> DBCALHit should come from mcsmear and not the DBCALMCResponse_factory.
>>>
>>> -Matt
>>>
>>>
>>> On Feb 11, 2010, at 5:10 PM, David Lawrence wrote:
>>>
>>>
>>>> Hi Matt,
>>>>
>>>> I'm invoking the 3-e-mail exchange rule and cc-ing this to the
>>>> halld-cal list....
>>>>
>>>>
>>>> Perhaps it's just semantics. I see 2 levels of "truth" information.
>>>> The first is the energy of the photon incident on the calorimeter and the
>>>> second is the energies deposited in the individual detectors. The
>>>> pre-smeared energy in the individual detector represents the "true energy
>>>> deposited", but does not represent the "measured energy". Since it is
>>>> unrealistically good, we should tag it as such. The string "HDDM" is
>>>> really unrelated to whether the data is "truth" or "digitized" so doesn't
>>>> serve that purpose very well.
>>>> We currently have the incident photon energy in DBCALTruthShower
>>>> (which is not particularly well named either since it contains only
>>>> information that exists prior to the shower occurring). Nonetheless,
>>>> DBCALTruthHit doesn't overlap with that name and would seem, at least to
>>>> me to be fairly descriptive of the information it contains.
>>>>
>>>> The FCAL actually ends up having 3 objects:
>>>>
>>>> DFCALTruthShower
>>>> DFCALHit:TRUTH
>>>> DFCALHit
>>>>
>>>> The DFCALHit object is used for both "truth" hits (DFCALHit:TRUTH) and
>>>> "digitized" hits (DFCALHit). This is possible since there is a 1-to-1
>>>> correspondence between the information coming from hdgeant and the
>>>> digitzed values used in the reconstruction. The BCAL, as you say, has a
>>>> single hit coming from hdgeant that must be turned into 2 hits before
>>>> starting the reconstruction. This means you can't really recycle classes
>>>> in the same way. The point being, however, that there are effectively 3
>>>> objects in the FCAL as well. The DBCALTruthHit would then just correspond
>>>> to DFCALHit:TRUTH.
>>>>
>>>> Regards,
>>>> -David
>>>>
>>>>
>>>>
>>>> Matthew Shepherd wrote:
>>>>
>>>>> Hi David,
>>>>>
>>>>> I"m not sure 1 is possible. The truth hit and hddm hit are
>>>>> fundamentally different things. Truth hit is the location of a true
>>>>> photon that struck the BCAL, more like a truth _shower_, while HDDM hit
>>>>> is the energy deposition from GEANT in a single cell. This then energy
>>>>> deposition then has to be turned into two hits, one for upstream and one
>>>>> for downstream sensors. I agree this would be better done in 1.
>>>>>
>>>>> I don't think the FCAL code behaves as you say. Note there are two
>>>>> classes in FCAL also: DFCALTruthShower and DFCALHit. This again, is
>>>>> the fundamental difference between energy deposition in a cell and
>>>>> clustered hits, which represent actual photons (which can then be
>>>>> compared to truth information).
>>>>>
>>>>> Moving code to mcsmear is a good idea. I think I volunteered to do
>>>>> that, once we had an agreement on how MC smear would handle the fact
>>>>> that the class it read in DBCALHDDMHit (1 instance per cell) has a
>>>>> different structure than the class it writes out DBCALHit (2 instances
>>>>> per cell).
>>>>>
>>>>> -Matt
>>>>>
>>>>> On Feb 11, 2010, at 1:54 PM, David Lawrence wrote:
>>>>>
>>>>>
>>>>>
>>>>>> Hi All,
>>>>>>
>>>>>> IMHO the "HDDM" was intended to indicate some type of low-level
>>>>>> information that is contained directly in the HDDM file. I would
>>>>>> suggest that to be more consistent with our current naming conventions
>>>>>> that we do one of the following:
>>>>>>
>>>>>> 1. Rename "DHDDMBCALHit" to "DBCALTruthHit". This follows our agreed
>>>>>> upon (and often not followed) convention to include the word "truth" in
>>>>>> the names of objects that carry information that will not be available
>>>>>> in the real data.
>>>>>>
>>>>>> 2. Re-tool things to follow the scheme used for the FCAL where there is
>>>>>> only one class, DFCALHit, but the un-smeared objects have the tag
>>>>>> "TRUTH" and the smeared ones have no tag. This may not be as easy (or
>>>>>> even desirable) for the BCAL due to the double ended readout.
>>>>>>
>>>>>> I would volunteer to implement 1. if there was general agreement.
>>>>>> Implementing 2 would be better done while moving the smearing code from
>>>>>> the reconstruction into mcsmear since it involves a little more
>>>>>> manipulation so I'm not quite volunteering for that yet.
>>>>>>
>>>>>> Again, just my opinion.
>>>>>>
>>>>>> Regards,
>>>>>> -David
>>>>>>
>>>>>> Zisis Papandreou wrote:
>>>>>>
>>>>>>
>>>>>>> Hello Matt: thanks for clarifying this. Cheers, Zisis...
>>>>>>>
>>>>>>> On 2010-02-10, at 8:11 PM, Matthew Shepherd wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> DBCALHit is the thing that most clearly resembles raw data. as this
>>>>>>>> is effectively the signal coming out of a photosensor. However,
>>>>>>>> DHDDMBCALHit cannot be dropped since it is needed to deliver the
>>>>>>>> energy deposition in a cell (what Geant actually tracks) to the
>>>>>>>> framework. In the framework, the "digitization" process is completed
>>>>>>>> and the DBCALHit objects are produced.
>>>>>>>>
>>>>>>>> -Matt
>>>>>>>>
>>>>>>>> On Feb 10, 2010, at 6:21 PM, Zisis Papandreou wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>> David, Matt: Any idea?
>>>>>>>>>
>>>>>>>>> Thanks, Zisis...
>>>>>>>>>
>>>>>>>>> Begin forwarded message:
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> From: Blake Leverington <leverinb at uregina.ca>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Date: February 10, 2010 5:15:54 PM GMT-06:00
>>>>>>>>>> To: Zisis Papandreou
>>>>>>>>>> <zisis at uregina.ca>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Cc: Matt Shepherd
>>>>>>>>>> <mashephe at indiana.edu>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Subject: Re: Fwd: BCAL objects in DANA
>>>>>>>>>>
>>>>>>>>>> I'm not the one to answer this. I've never looked at that file
>>>>>>>>>> before.
>>>>>>>>>>
>>>>>>>>>> -Blake
>>>>>>>>>>
>>>>>>>>>> On 10/02/10 04:57 PM, Zisis Papandreou wrote:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>> Hi guys:
>>>>>>>>>>>
>>>>>>>>>>> can one of you answer Elliott and cc: me?
>>>>>>>>>>>
>>>>>>>>>>> Thanks, Zisis...
>>>>>>>>>>>
>>>>>>>>>>> Begin forwarded message:
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>> From: Elliott Wolin <wolin at jlab.org>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Date: February 10, 2010 2:51:18 PM GMT-06:00
>>>>>>>>>>>> To: Zisis Papandreou
>>>>>>>>>>>> <Zisis.Papandreou at uregina.ca>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Cc: Mark Ito
>>>>>>>>>>>> <marki at jlab.org>, David Lawrence <davidl at jlab.org>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Subject: BCAL objects in DANA
>>>>>>>>>>>>
>>>>>>>>>>>> Hi Zisis,
>>>>>>>>>>>>
>>>>>>>>>>>> I see DBCALHit.h and DHDDMBCALHit.h in the repository. They are
>>>>>>>>>>>> very similar. Which one represents the HDDM data the best, i.e.
>>>>>>>>>>>> the one I should dump to EVIO files? Also, can one be eliminated
>>>>>>>>>>>> since they are so similar? And whatever remains should be called
>>>>>>>>>>>> DBCALHit.h (drop HDDM in the name).
>>>>>>>>>>>>
>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>>
>>>>>>>>>>>> Sincerely,
>>>>>>>>>>>> Elliott
>>>>>>>>>>>>
>>>>>>>>>>>> ================================================================================
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Those raised in a morally relative or neutral environment will
>>>>>>>>>>>> hold
>>>>>>>>>>>> no truths to be self-evident.
>>>>>>>>>>>>
>>>>>>>>>>>> Elliott Wolin
>>>>>>>>>>>> Staff Physicist, Jefferson Lab
>>>>>>>>>>>> 12000 Jefferson Ave
>>>>>>>>>>>> Suite 8 MS 12A1
>>>>>>>>>>>> Newport News, VA 23606
>>>>>>>>>>>> 757-269-7365
>>>>>>>>>>>>
>>>>>>>>>>>> ================================================================================
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>> ---
>>>>>>>>>>> Dr. Zisis Papandreou | email:
>>>>>>>>>>> zisis at uregina.ca
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Department of Physics | tel. : (306) 585-5379
>>>>>>>>>>> University of Regina | tel. : (306) 585-4149
>>>>>>>>>>> Regina, SK S4S 0A2 | fax. : (306) 585-5659
>>>>>>>>>>> World Wide Web:
>>>>>>>>>>> http://www.phys.uregina.ca/sparro/zisis/
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>> ---
>>>>>>>>> Dr. Zisis Papandreou | email:
>>>>>>>>> zisis at uregina.ca
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Department of Physics | tel. : (306) 585-5379
>>>>>>>>> University of Regina | tel. : (306) 585-4149
>>>>>>>>> Regina, SK S4S 0A2 | fax. : (306) 585-5659
>>>>>>>>> World Wide Web:
>>>>>>>>> http://www.phys.uregina.ca/sparro/zisis/
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>> ---
>>>>>>> Dr. Zisis Papandreou | email:
>>>>>>> zisis at uregina.ca
>>>>>>>
>>>>>>>
>>>>>>> Department of Physics | tel. : (306) 585-5379
>>>>>>> University of Regina | tel. : (306) 585-4149
>>>>>>> Regina, SK S4S 0A2 | fax. : (306) 585-5659
>>>>>>> World Wide Web:
>>>>>>> http://www.phys.uregina.ca/sparro/zisis/
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>> --
>>>>>>
>>>>>>
>>>>>> ------------------------------------------------------------------------
>>>>>> David Lawrence Ph.D.
>>>>>> Staff Scientist Office: (757)269-5567 [[[ [ [ [
>>>>>> Jefferson Lab Pager: (757)584-5567 [ [ [ [ [ [
>>>>>> http://www.jlab.org/~davidl davidl at jlab.org
>>>>>>
>>>>>> [[[ [[ [[ [[[
>>>>>>
>>>>>> ------------------------------------------------------------------------
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>> --
>>>>
>>>> ------------------------------------------------------------------------
>>>> David Lawrence Ph.D.
>>>> Staff Scientist Office: (757)269-5567 [[[ [ [ [
>>>> Jefferson Lab Pager: (757)584-5567 [ [ [ [ [ [
>>>> http://www.jlab.org/~davidl davidl at jlab.org
>>>> [[[ [[ [[ [[[
>>>> ------------------------------------------------------------------------
>>>>
>>>>
>>>>
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