I'm not aware of any neutrino measurements detecting neutrons in a final
state.
GENIE is based on models and backed with data whenever possible. Other
probes,
protons and pions have results for neutrons in the final state, we
validate with that data.
Steve
On 10/29/2013 11:46 PM, Zhe Wang wrote:
> Hi Steve,
>
> I haven't made my question clear enough.
> I was curious about whether the neutron fraction should be that high?
> 30% chances there is a free neutron produced with a 90-100 MeV
> electron neutrino.
> Is this over-estimated or under-estimated by Genie?
> To what level it will be more realistic?
> Thank you.
>
> --
> Cheers,
> Zhe Wang
>
> On 10/29/2013 9:51 PM, Steven Dytman wrote:
>> Zhe,
>> Genie simulates neutrino nucleus interactions. The neutrino has some
>> interaction
>> in the nuclear volume followed by FSI. It produces particles at the
>> outside of the
>> nucleus. What you do with them is up to you, depends on your
>> application.
>>
>> regards,
>> Steve
>>
>> On 10/28/2013 03:23 AM, Zhe Wang wrote:
>>> Hi Steve,
>>>
>>> I simulated 10000 nu_e (90-100 MeV) with carbon 12 target.
>>> About 7000 are CC events, almost all of them have at least one free
>>> proton.
>>> In them, there are 2200 events with a free neutron in the final
>>> states produced
>>> with the same mechanism. So the fraction is indeed high and raised
>>> my attention.
>>>
>>> So I am wondering what is the best (reasonable) treatment for them?
>>> Shall I just considering the proton kinetic energy and ignore these
>>> neutrons?
>>> Do you have some suggestions? Thank you.
>>>
>>> --
>>> Cheers,
>>> Zhe Wang
>>>
>>>
>>> On 10/27/2013 10:43 PM, Steve Dytman wrote:
>>>> It is the result of a final state interaction (FSI) of type
>>>> 4=inelastic.
>>>> This event shows other problems that we are working on.
>>>>
>>>> Steve
>>>>
>>>> On 10/27/2013 6:55 AM, Zhe Wang wrote:
>>>>> Dear expert,
>>>>>
>>>>> I am trying to understand a snip of the generation log file.
>>>>> I don't quite understand how the track no. 7, neutron is generated.
>>>>> Do you know why? Thank you in advance.
>>>>>
>>>>> --
>>>>> Cheers,
>>>>> Zhe Wang
>>>>>
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> |GENIE GHEP Event Record [print level: 3] |
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> | Idx | Name | Ist | PDG | Mother | Daughter
>>>>> | Px | Py | Pz | E | m |
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> | 0 | nu_e | 0 | 12 | -1 | -1 | 4 | 4 |
>>>>> 0.000 | 0.000 | 0.100 | 0.100 | 0.000 |
>>>>> | 1 | C12 | 0 | 1000060120 | -1 | -1 | 2 | 3 |
>>>>> 0.000 | 0.000 | 0.000 | 11.179 | 11.179 |
>>>>> | 2 | neutron | 11 | 2112 | 1 | -1 | 5 | 5 |
>>>>> -0.046 | 0.148 | 0.072 | 0.934 | **0.940 | M = 0.919
>>>>> | 3 | C11 | 2 | 1000060110 | 1 | -1 | 8 | 8 |
>>>>> 0.046 | -0.148 | -0.072 | 10.245 | 10.243 |
>>>>> | 4 | e- | 1 | 11 | 0 | -1 | -1 | -1 |
>>>>> 0.025 | -0.043 | -0.023 | 0.054 | 0.001 | P =
>>>>> (-0.461,0.783,0.418)
>>>>> | 5 | proton | 14 | 2212 | 2 | -1 | 6 | 7 |
>>>>> -0.071 | 0.190 | 0.194 | 0.979 | 0.938 | FSI = 4
>>>>> | 6 | proton | 1 | 2212 | 5 | -1 | -1 | -1 |
>>>>> -0.000 | 0.000 | -0.000 | 0.938 | 0.938 |
>>>>> | 7 | neutron | 1 | 2112 | 5 | -1 | -1 | -1 |
>>>>> -0.006 | -0.003 | 0.036 | 0.940 | 0.940 |
>>>>> | 8 | HadrBlob | 15 | 2000000002 | 3 | -1 | -1 | -1 |
>>>>> 0.032 | 0.009 | -0.008 | 9.315 | **0.000 | M = 9.315
>>>>> | 9 | NucBindE | 1 | 2000000101 | -1 | -1 | -1 | -1 |
>>>>> -0.019 | 0.053 | -0.087 | 0.025 | **0.000 | M = -0.100
>>>>> | 10 | NucBindE | 1 | 2000000101 | -1 | -1 | -1 | -1 |
>>>>> -0.031 | -0.016 | 0.181 | 0.025 | **0.000 | M = -0.183
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> | Fin-Init: | -0.000 | 0.000 | 0.000 | 0.019 | |
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> | Vertex: nu_e @ (x = 0.00000 m, y = 0.00000
>>>>> m, z = 0.00000 m, t = 0 s) |
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> | Err flag [bits:15->0] : 0000000000000000 | 1st set: none |
>>>>> | Err mask [bits:15->0] : 1111111111111111 | Is unphysical:
>>>>> NO | Accepted: YES |
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>> | sig(Ev) = 1.7352e-39 cm^2 | dsig(Q2;E)/dQ2 = 2.8019e-38
>>>>> cm^2/GeV^2 | Weight = 1 |
>>>>> |------------------------------------------------------------------------------------------------------------------|
>>>>>
>>>>>
>>>>>
>>>>> --------------------------------------------------------------------------------------------------------------
>>>>>
>>>>> GENIE Interaction Summary
>>>>> --------------------------------------------------------------------------------------------------------------
>>>>>
>>>>> [-] [Init-State]
>>>>> |--> probe : PDG-code = 12 (nu_e)
>>>>> |--> nucl. target : Z = 6, A = 12, PDG-Code = 1000060120 (C12)
>>>>> |--> hit nucleon : PDC-Code = 2112 (neutron)
>>>>> |--> hit quark : no set
>>>>> |--> probe 4P : (E = 0.0995661, Px = 0, Py = 0,
>>>>> Pz = 0.0995661)
>>>>> |--> target 4P : (E = 11.179, Px = 0, Py = 0,
>>>>> Pz = 0)
>>>>> |--> nucleon 4P : (E = 0.9342, Px = -0.0456271, Py =
>>>>> 0.147645, Pz = 0.0720215)
>>>>> [-] [Process-Info]
>>>>> |--> Interaction : Weak[CC]
>>>>> |--> Scattering : QES
>>>>> [-] [Kinematics]
>>>>> |--> *Selected* Bjorken x = 0.294936
>>>>> |--> *Selected* Inelasticity y = 0.303082
>>>>> |--> *Selected* Momentum transfer Q2 (>0) = 0.0153471
>>>>> |--> *Selected* Hadronic invariant mass W = 0.93827
>>>>> [-] [Exclusive Process Info]
>>>>> |--> charm prod. : false
>>>>> |--> f/s nucleons : N(p) = 0 N(n) = 0
>>>>> |--> f/s pions : N(pi^0) = 0 N(pi^+) = 0 N(pi^-) = 0
>>>>> |--> resonance : [not set]
>>>>> --------------------------------------------------------------------------------------------------------------
>>>>>
>>
>
>
|