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Re: [Fwd: Re: Hall D collimator cave simulation needed by RadCon]



Thanks a lot Pavel !

It seems that fluxes of all particle types are very small
(I will compare them with the fluxes I've obtained using
our Geant; as expected, they look very similar).

I will post your slides to the GlueX wiki page.

Cheers,
        Sascha




On Thu, 28 May 2009, Pavel Degtiarenko wrote:

> Hi Alex,
> Attached please find the plots for radial flux distribution at the plane 
> z=-90 cm, both incoming and outgoing. Unless something is totally wrong, it 
> seems that the new design of the beam line have killed essentially all 
> background coming from the cave, compared with the backscattering. Neutron 
> statistics is poor, I would need a new MC run with cross sections amplified 
> to see neutrons better. -- After I'm back at JLab in mid-June.
> Regards,
> Pavel
>
>
>
> Alexander Somov wrote:
>> 
>> Hi Pavel,
>> 
>> Thanks a lot for very interesting plots. It  seems that our current design 
>> of the cave reduces the dose rate in the experimental
>> hall.
>> 
>> Would it be a lot of efforts for you to plot doses in front of
>> the GlueX detector (let's say at z=-1m) as a function of the radial 
>> distance from the beamline ?
>> 
>> Thanks,
>>        Alex
>> 
>> 
>> 
>> On Tue, 26 May 2009, Pavel Degtiarenko wrote:
>> 
>>> Hi Dianne,
>>> The revised calculation results for dose rates in the Hall D and inside 
>>> the cave may be found in the attached file "hd2009_v01.pdf", in the same 
>>> format as the previous set of plots made about a year ago (file 
>>> "hd2008_v01.pdf"). The new set is done using the new GEANT geometry files 
>>> that Alexander had sent me recently. The result is that the new geometry 
>>> provides more shielding for the beam line entering the Hall, thus 
>>> decreasing dose rates in the Hall to a minimum, mostly determined by the 
>>> inevitable scattering in the target, and backscattering from the photon 
>>> dump. Change of the average dose rates inside the cave is small.
>>> Regards,
>>> Pavel
>>> 
>>> 
>>> 
>>> Dianne Napier wrote:
>>>> 
>>>> Sincerely,
>>>> 
>>>> Dianne Napier
>>>> dnapier@jlab.org
>>>> 12GeV Integration Engineer
>>>> Ph:   757-269-7475
>>>> Cell: 757-768-8539
>>>> Pgr:  757-584-7475
>>>> Fax:  757-269-7691
>>>> 
>>>> Pavel,
>>>> 
>>>> Please let me know the status of this simulation.  do you plan to have it 
>>>> finished by the end of this month?
>>>> 
>>>> thanks,
>>>> 
>>>> dianne napier
>>>> 12GeV integration engineer
>>>> 
>>>>> 
>>>>> 
>>>>> -------- Original Message --------
>>>>> Subject:     Re: Hall D collimator cave simulation needed by RadCon
>>>>> Date:     Wed, 29 Apr 2009 10:44:01 -0400
>>>>> From:     Pavel Degtiarenko <pavel@jlab.org>
>>>>> To:     welch@jlab.org
>>>>> CC:     Dianne Napier <dnapier@jlab.org>, Vashek Vylet <vylet@jlab.org>
>>>>> References:     <49F846DE.3020106@jlab.org> 
>>>>> <55374.129.57.72.84.1241014949.squirrel@webmail.jlab.org>
>>>>> 
>>>>> 
>>>>> 
>>>>> Hi Keith
>>>>> I believe the redesign mostly relates to shielding arrangements inside 
>>>>> the cave and it will not change dramatically dose rates in the Hall. It 
>>>>> wasn't supposed to affect civil layouts. I will try to run their new 
>>>>> geometry and get some answers by mid-May.
>>>>> Regards,
>>>>> Pavel
>>>>> 
>>>>> 
>>>>> welch@jlab.org wrote:
>>>>>> Pavel,
>>>>>> 
>>>>>> Didn't we (you) explain this to somebody a while back, that the final
>>>>>> design was based on imput based on the  modeling of the precursor 
>>>>>> design?
>>>>>> 
>>>>>> Or is this something new - have they actually done a real "redesign" 
>>>>>> that
>>>>>> we need to have a look at?
>>>>>> 
>>>>>> Keith
>>>>>> 
>>>>>> 
>>>>>>> Pavel/Keith,
>>>>>>> 
>>>>>>> I have been working intensely with Hall D as they are the first up for
>>>>>>> installation.
>>>>>>> 
>>>>>>> There is an open issue concerning the collimator cave redesign.
>>>>>>> 
>>>>>>> Hall D has mentioned that you previously did a simulation on a 
>>>>>>> previous
>>>>>>> design, but a new simulation on the new layout is still needed.
>>>>>>> 
>>>>>>> The current Shield document  doesn't match the new layout/design.
>>>>>>> 
>>>>>>> As well, requirement changes resulting from a new simulation could
>>>>>>> affect materials and additional shielding or relocation of equipment.
>>>>>>> And may also affect outside shielding being done by the Civil portion 
>>>>>>> of
>>>>>>> this project.  At best, there will be minimal to no changes with the 
>>>>>>> new
>>>>>>> layout. But any changes must be know as soon as possible so scope
>>>>>>> changes can be requested and processed in time to meet any new
>>>>>>> requirements.
>>>>>>> 
>>>>>>> Hall D has stated that they have previously sent you the geometry 
>>>>>>> files
>>>>>>> for the simulation of the detector that is needed for this new layout
>>>>>>> radiation simulation.
>>>>>>> 
>>>>>>> Please let me know the status/ where this is at on your list and if
>>>>>>> there is any additional information needed from hall d or myself to 
>>>>>>> help
>>>>>>> push this along.
>>>>>>> 
>>>>>>> 
>>>>>>> -- 
>>>>>>> Sincerely,
>>>>>>> 
>>>>>>> Dianne Napier
>>>>>>> dnapier@jlab.org
>>>>>>> 12GeV Integration Engineer
>>>>>>> Ph:   757-269-7475
>>>>>>> Cell: 757-768-8539
>>>>>>> Pgr:  757-584-7475
>>>>>>> Fax:  757-269-7691
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>> 
>>>>> 
>>>>> -- 
>>>>> Sincerely,
>>>>> 
>>>>> Dianne Napier
>>>>> dnapier@jlab.org
>>>>> 12GeV Integration Engineer
>>>>> Ph:   757-269-7475
>>>>> Cell: 757-768-8539
>>>>> Pgr:  757-584-7475
>>>>> Fax:  757-269-7691
>>> 
>>> 
>
>