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Attached is Moller events with both e- in the ECal.  I increased the ECal acceptance by 1/2 crystal width in the removed crystal region; Ycut = 3.3 - 0.65 = 2.65 cm. The energy distribution in solid red is for those Mollers with both e- detected in ECal.  Moller acceptance is sensitive to the positions and shower development in crystals # -8 and -9. 

Takashi

-----Original Message-----
From: Valery Kubarovsky [mailto:[log in to unmask]] 
Sent: Saturday, May 14, 2016 11:43 AM
To: Maruyama, Takashi
Cc: Uemura, Sho; Bradley T Yale; Maurik Holtrop; [log in to unmask]; hps-software; Graf, Norman A.; Stepan Stepanyan
Subject: Re: [Hps-analysis] Moller Generator Fixed! (again)

Hi Takashi,
We don't need shower simulation and real EC response to understand do we have dip in the Moller energy distribution or bump.  We cannot resolve this question for months. You have flat distribution but without geometrical cut on both electrons. One more step and you will get something similar to our data I guess.
Regards,
Valery

----- Original Message -----
> From: "Takashi Maruyama" <[log in to unmask]>
> To: "Valery Kubarovsky" <[log in to unmask]>
> Cc: "Sho Uemura" <[log in to unmask]>, "Bradley T Yale" <[log in to unmask]>, "Maurik Holtrop"
> <[log in to unmask]>, [log in to unmask], "hps-software" <[log in to unmask]>, "Norman A. Graf"
> <[log in to unmask]>, "Stepan Stepanyan" <[log in to unmask]>
> Sent: Saturday, May 14, 2016 1:45:01 PM
> Subject: Re: [Hps-analysis] Moller Generator Fixed! (again)

> Hi Valery,
> 
> My cut is simple geometrical cut: the crystal edge is 2 cm from the 
> beam, and the removed crystal edge is 2+1.3 = 3.3 cm. No shower 
> simulation is made. What I can conclude with my fast tracking is that 
> I don’t see any problem in the Moller events that Brad generated at 
> the stdhep level. Real ECal response and trigger should be answered by SLIC. These are beyond my fast tracking.
> 
>  Takashi
>> On May 14, 2016, at 10:05 AM, Valery Kubarovsky <[log in to unmask]> wrote:
>> 
>> Hi Takashi,
>> Thanks for the prompt reply. So you are saying that the we have no 
>> acceptance for Moller electrons at all.
>> Your conclusion is in contradiction with Geant MC and our data, I believe.
>> It will be interesting to understand the reason.
>> - Did you really apply the geometrical cut or made your conclusion 
>> based on your first picture by eye? Picture N2 shows that 1.15 GeV 
>> electrons has X=(-10,-15)cm spread.
>> - The solid line is just the edge of the crystals at the face of the 
>> calorimeter, correct?
>> - What if we will apply the crystal's edge cut at the back of the 
>> calorimeter, not at the front face?
>> - We have 30 mrad angle for beam particles on our target. Do you have 
>> it in your fast MC?
>> - Can you make your plots for the electrons that have hit in the calorimeter?
>> 
>> Thanks again,
>> Valery
>> 
>> 
>> 
>> ----- Original Message -----
>>> From: "Takashi Maruyama" <[log in to unmask]>
>>> To: "Valery Kubarovsky" <[log in to unmask]>
>>> Cc: "Sho Uemura" <[log in to unmask]>, "Bradley T Yale"
>>> <[log in to unmask]>, "Maurik Holtrop"
>>> <[log in to unmask]>, [log in to unmask], "hps-software"
>>> <[log in to unmask]>, "Norman A. Graf"
>>> <[log in to unmask]>
>>> Sent: Friday, May 13, 2016 6:13:31 PM
>>> Subject: RE: [Hps-analysis] Moller Generator Fixed! (again)
>> 
>>> Hi Valery,
>>> 
>>> Attached is the distributions you requested. These are Brad's EGS5 
>>> generated Mollers. If I use the solid lines to represent the crystal 
>>> edges, one of the Moller electrons always falls in this removed 
>>> crystal area; ie both e-'s cannot be detected by ECal.
>>> 
>>> Takashi
>>> 
>>> -----Original Message-----
>>> From: Valery Kubarovsky [mailto:[log in to unmask]]
>>> Sent: Friday, May 13, 2016 12:08 PM
>>> To: Maruyama, Takashi
>>> Cc: Uemura, Sho; Bradley T Yale; Maurik Holtrop; 
>>> [log in to unmask]; hps-software; Graf, Norman A.
>>> Subject: Re: [Hps-analysis] Moller Generator Fixed! (again)
>>> 
>>> Hi Takashi,
>>> 
>>> Can you make a several plots from your fast MC:
>>> 
>>> 1. Y vs X of the tracks at the face-off the calorimeter:
>>> 2. The same plot when both of tracks are detected by Ecal 3. The 
>>> energy distribution of the electrons for the events when both tracks detected by Ecal.
>>> 
>>> I think that it is not very difficult for you.
>>> The main question to resolve will get the dip in the energy 
>>> distribution or bump at the E=Ebeam/2.
>>> 
>>> Thanks in advance,
>>> Valery
>>> 
>>> 
>>> 
>>> ----- Original Message -----
>>>> From: "Takashi Maruyama" <[log in to unmask]>
>>>> To: "Sho Uemura" <[log in to unmask]>, "Bradley T Yale"
>>>> <[log in to unmask]>
>>>> Cc: "Maurik Holtrop" <[log in to unmask]>, 
>>>> [log in to unmask], "hps-software" <[log in to unmask]>, "Valery Kubarovsky"
>>>> <[log in to unmask]>, "Norman A. Graf" <[log in to unmask]>
>>>> Sent: Friday, May 13, 2016 1:28:29 PM
>>>> Subject: RE: [Hps-analysis] Moller Generator Fixed! (again)
>>> 
>>>> Thanks, Sho. I was going to say exactly the same thing. Attached is 
>>>> Moller distribution at layer 6 in my fast tracking using Brad's 
>>>> Moller events. Moller problem is somewhere else.
>>>>  Takashi
>>>> 
>>>> -----Original Message-----
>>>> From: [log in to unmask] 
>>>> [mailto:[log in to unmask]] On Behalf Of Sho Uemura
>>>> Sent: Friday, May 13, 2016 9:00 AM
>>>> To: Bradley T Yale
>>>> Cc: Maurik Holtrop; [log in to unmask]; hps-software; Valeri 
>>>> Koubarovski; Graf, Norman A.
>>>> Subject: Re: [Hps-analysis] Moller Generator Fixed! (again)
>>>> 
>>>> By the usual definition of theta_y (angle of elevation from the xz 
>>>> plane), the direction cosine cos(b) (where b is the angle of 
>>>> inclination from the
>>>> y-axis) exactly equals sin(theta_y).
>>>> 
>>>> What I meant to say is that in small angle, sin(theta_y)~=theta_y. 
>>>> The relation
>>>> sin(theta)sin(phi)=sin(theta_y) is exact.
>>>> 
>>>> On Fri, 13 May 2016, Bradley T Yale wrote:
>>>> 
>>>>> Even if theta is a small angle, it is multiplied by sin(phi), where phi is not.
>>>>> ________________________________________
>>>>> From: [log in to unmask] 
>>>>> <[log in to unmask]> on behalf of Sho Uemura 
>>>>> <[log in to unmask]>
>>>>> Sent: Friday, May 13, 2016 11:00:46 AM
>>>>> To: Maurik Holtrop
>>>>> Cc: Bradley T Yale; [log in to unmask]; HPS Software; Valeri 
>>>>> Koubarovski; Norman A. Graf
>>>>> Subject: Re: [Hps-analysis] Moller Generator Fixed! (again)
>>>>> 
>>>>> I don't understand - I thought this cut was intended as a theta_y 
>>>>> cut
>>>>> (>10 mrad above or below the beam plane,so we only keep particles 
>>>>> that might hit a detector), and does v(np) not correctly describe theta_y?
>>>>> 
>>>>> So I buy that this explains the difference in the envelope of your 
>>>>> MC truth distribution from theory (the U shape) but not that this 
>>>>> has anything to do with the gap, or any data-MC discrepancy seen 
>>>>> after readout.
>>>>> 
>>>>> On Fri, 13 May 2016, Maurik Holtrop wrote:
>>>>> 
>>>>>> Hi Bradley,
>>>>>> 
>>>>>> That is great investigative work. You should now indeed check the 
>>>>>> other EGS5 generators for similar issues. As we discussed 
>>>>>> yesterday, there may be an issue with the background events for tridents.
>>>>>> 
>>>>>> Can you please mention (advertise) this new result at the 
>>>>>> analysis meeting today?
>>>>>> 
>>>>>> Best,
>>>>>>      Maurik
>>>>>> 
>>>>>> 
>>>>>>> On May 13, 2016, at 3:25 AM, Bradley T Yale <[log in to unmask]> wrote:
>>>>>>> 
>>>>>>> I think I found the real problem with how the Moller generator 
>>>>>>> was initially set up.
>>>>>>> This one affects the generated distribution a LOT more than the 
>>>>>>> RNG precision probably did, and explains the remaining 
>>>>>>> strangeness in the generated distribution.
>>>>>>> 
>>>>>>> Looking at the egs5 Moller procedure, the angular cut was defined as:
>>>>>>> 
>>>>>>> abs(v(np)) > 0.010 radians
>>>>>>> 
>>>>>>> where v(np) is supposed to be theta.
>>>>>>> However, the variables u, v, and w in egs are actually 
>>>>>>> directional cosines, p_x = p*u,   p_y = p*v,   and   p_z = p*w.
>>>>>>> 
>>>>>>> So this means that in reality, the generator was saving Moller 
>>>>>>> events such that abs [ sin(theta)*sin(phi) ] > 0.010
>>>>>>> 
>>>>>>> which has a periodic nature to it. Plot this equation for some 
>>>>>>> value of phi (or just think about it) and you'll see what was 
>>>>>>> likely making these strange hills and gaps in the energy 
>>>>>>> distribution - full-wave rectified Mollers!
>>>>>>> 
>>>>>>> The scattered beam simulation does correctly define theta though:
>>>>>>> sqrt[ u^2 + v^2 ]
>>>>>>> 
>>>>>>> I made a moller_v3 procedure with this correction (still with a 
>>>>>>> >10 mrad cut), and the comparison between before and after is shown.
>>>>>>> The generated events now agree with the calculated cross section 
>>>>>>> (XS curve is shown on the 'bad' plot), and no apparent missing events.
>>>>>>> 
>>>>>>> These will be run through recon to see if we can finally get 
>>>>>>> good Moller agreement with data.
>>>>>>> I'm also going to try changing the scattered beam energy cut 
>>>>>>> shown in the software meeting to see if it fixes Tim's phi vs. energy discrepancy.
>>>>>>> -Brad
>>>>>>> <BadMollers.png><2pt3_mol_v3_moller_E.png>______________________
>>>>>>> ___
>>>>>>> _
>>>>>>> _____________________
>>>>>>> Hps-analysis mailing list
>>>>>>> [log in to unmask] <mailto:[log in to unmask]> 
>>>>>>> https://mailman.jlab.org/mailman/listinfo/hps-analysis
>>>>>>> <https://mailman.jlab.org/mailman/listinfo/hps-analysis>
>>>>>> 
>>>>> 
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