[Isotope-prod] Updated draft narrative

Pavel Degtiarenko pavel at jlab.org
Mon Jun 27 10:09:28 EDT 2016


Dear Hari,

We will see some indirect activation by neutrons from the 
Be-9(gamma,n)Be-8 reaction, where the threshold is low (1.665 MeV). Be-8 
decays to 2 alphas.

There will be no Be-7 production up to ~20 MeV.

B-10(gamma,n)B-9 threshold is 8.437 MeV; B-9 decays immediately to Be-9 
- no long lived isotopes.

N-14(gamma,n)N-13 threshold is just above 10 MeV, so no production 
there. But at higher energy that will produce a lot of short-lived 
activity (~10 min half lifetime).

If we limit the beam energy at 6 MeV the only source of activation will 
be indirect neutrons from the Be-9(gamma,n)Be-8 reaction.  I do not 
expect a problem here, but it should be evaluated before planning the 
tests.

Best regards,
Pavel



On 06/27/2016 08:35 AM, Hari Areti wrote:
> Dear Pavel,
> Thanks for the input.
>
> You are absolutely right abouth hBN, I will add to the narrative,
> we do not know what radiation does to hBN's integrity and its
> properties (thermal conductivity). That is another piece of data
> that will result from this R&D. If hBN fails, we have a fall back
> in ceramic insert.
>
> Two more things that you can shed light on.
>
> We claim that low energy tests at LERF will eliminate or reduce
> local activity. Keeping to around 6 MeV will help with tungsten
> and copper. Is this true for Be and BN?
>
>
> Thanks.
>
> -H
>
>
> ------------------------------------------------------------------------
> *From: *"Pavel Degtiarenko" <pavel at jlab.org>
> *To: *"isotope-prod" <isotope-prod at jlab.org>
> *Sent: *Sunday, June 26, 2016 6:50:08 PM
> *Subject: *Re: [Isotope-prod] Updated draft narrative
>
> Dear Hari,
>
> Several remarks:
> 1. On pages 3 and 4 the subtitle " /Photo-production Principles" /is 
> repeated twice. The second one should probably be " /Photo-production 
> Process"/
>
> 2. On page 5 the typos are is in the reaction description (67 should 
> be superscript, and the reaction should be "gamma,alpha"):
>
> "Similarly, 67Cu can be produced via the ^71 Ga (g, p) ^67 Cu 
> reaction, as in this proposal."
>
>
> 3. Page 8, last line needs the dot at the end:
>
> "including studies of targeted hybrid probes"
>
> 4. Page 16, discussion of the parasitic test at 10 MeV, the statement
>
> "This is not a surprising result because the energy threshold for 
> production is higher."
>
> should be "This is not a surprising result because while the beam 
> energy is above the production threshold, the cross section for the 
> alpha particle emission is suppressed by the nuclear Coulomb barrier."
>
> 5.  Page 17, correct "stay below the ^69 Ga(g, 2n)^67 Ga because " to 
> " stay below the ^69 Ga(g, 2n)^67 Ga reaction threshold because "
>
>
> 6.  I think that at present we don't really have a proof that hBN 
> target holder will perform as we say it will. One of the questions to 
> be answered by the tests is how well this material will withstand the 
> radiation damage. We know that chemical structure of hBN is close to 
> graphite. There are studies on the rad. damage to graphite, causing 
> displacements in the crystal structure and loss of thermal 
> conductivity. I think we should mention somewhere that we know about 
> the issue, will do dedicated testing, and will consider alternatives 
> if hBN won't work.
>
> Best regards,
> Pavel
>
> On 6/26/2016 4:28 PM, Hari Areti wrote:
>
>     I have updated two sections at the end of the narrative.
>     It is in the dropbox folder 24June2016 and later. The name
>     is 26June2016 draft narrative.
>
>     Section on objectives - rearranged the items.
>
>     Elaborated the summary to ensure that the elements mentioned in
>     the FOA
>     are addressed. You may want to elaborate.
>
>     -H
>
>     The elements are:
>
>
>       * clearly describe how the outcome  would support and enhance
>         the production of isotopes used for research and applications
>         in medicine, homeland security, the physical sciences,
>         biological and geological sciences, energy, industry, etc.
>       * incorporate effective ways to train personnel with essential
>         knowledge and skills related to the production, processing,
>         purification, and distribution of enriched stable and
>         radioactive isotopes
>       * Novel or improved capabilities for inducing transmutation of
>         atoms in targets to create radioisotopes;
>       * Optimum selection of the materials and effective design of
>         targets for the production of radioisotopes;
>       * Innovative approaches to model and predict behavior of targets
>         undergoing irradiation in order to optimize yield and minimize
>         target failures during routine isotope production;
>       * Chemical and physical processes to recover and purify
>         radioisotopes from activated targets, legacy materials, or
>         facility components;
>       * Automation of production and processing techniques to enhance
>         efficiency and safety of the production of radioisotopes; and
>       * Mass-separation for enriched stable isotopes and high specific
>         activity radioactive isotopes
>
>     Merit Review Criteria
>
>     `               Scientific and/or Technical Merit of the Project;
>
>       * What is the scientific innovation of proposed research?
>       * What is the likelihood of achieving valuable results?
>       * How might the results of the proposed work impact the
>         direction, progress, and thinking in relevant scientific
>         fields of research?
>       * How does the proposed work compare with other efforts in its
>         field, both in terms of scientific and/or technical merit and
>         originality?
>       * Is the Data Management Plan suitable for the proposed research
>         and to what extent does it support the validation of research
>         results?
>
>     Appropriateness of the Proposed Method or Approach;
>
>       * How logical and feasible are the research approaches?
>       * Does the proposed research employ innovative concepts or methods?
>       * Are the conceptual framework, methods, and analyses well
>         justified, adequately developed, and likely to lead to
>         scientifically valid conclusions?
>       * Does the applicant recognize significant potential problems
>         and consider alternative strategies?
>
>     Competency of Applicant’s Personnel and Adequacy of Proposed Resources
>
>       * What is the past performance and potential of the Principal
>         Investigator (PI)?
>       * How well qualified is the research team to carry out the
>         proposed research?
>       * Are the research environment and facilities adequate for
>         performing the research?
>       * Does the proposed work take advantage of unique facilities and
>         capabilities?
>
>
>
>
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