JKJ NewsLetter #3
Masatoshi ARAI
masatoshi.arai at kek.jp
Mon Jan 29 14:51:23 CST 2001
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JAERI-KEK Joint Project Newsletter No. 3 Jan., 2001
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High Intensity Proton Accelerator Project proposed jointly
by the Japan Atomic Energy Research Institute (JAERI)
and the High Energy Accelerator Research Organization (KEK)
http://jkj.tokai.jaeri.go.jp/
Editorial Board:
Masatoshi ARAI (chair): masatoshi.arai at kek.jp
Tomokazu FUKUDA: tomokazu.fukuda at kek.jp
Yujiro IKEDA: ikeda at fnshp.tokai.jaeri.go.jp
Hideaki YOKOMIZO: yokomizo at linac.tokai.jaeri.go.jp
Shinya SAWADA: shinya.sawada at kek.jp
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TOPICS
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1. The Project was approved for construction by the Government on 24
December, 2000.
2. Call for proposals for the project nickname until 15 February.
Please send a nickname and the brief description to
aisyo at linac.tokai.jaeri.go.jp
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CONTENTS
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0. Editorial Note
1. Recent Progress of the Joint Project between JAERI and KEK on High-
Intensity Proton Accelerators (Shoji NAGAMIYA)
2. Activities of the Accelerator Development Group (Yoshishige YAMAZAKI)
3. Recent Activities of Facilities Construction Group (Yo-ichi AKUTSU)
4. Report from the Accelerator Driven Transmutation (ADS)
Experimental Facility Group (Yujiro IKEDA)
5. Report from the Safety Analysis Group (Nobuo SASAMOTO)
6. Report on the Nuclear and Particle Physics Facility (Jun IMAZATO)
7. Report from the Muon Science Group (Yasuhiro MIYAKE)
8. Recent Activity of Neutoron Science Group. (Susumu IKEDA)
9. Conferences and Symposium
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0. Editorial Note
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This is the Joint Project Newsletter, which will be issued every 3months.
In case you do not wish to receive this Newsletter in the future, please
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You can get a help with a sentence of
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Information on the project can be also obtained at the Web site:
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1. Recent Progress of the Joint Project between JAERI and KEK on High-
Intensity Proton Accelerators
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by Shoji Nagamiya
This is the third volume of the Newsletter for the Joint Project
between JAERI and KEK on high-intensity proton accelerators. In the
special issue of the Newsletter distributed at the end of December,
I announced the exciting news that this project has been approved for
construction. Because this issue of the Newsletter is a regular one,
I would like to describe the progress for the three-month period since
October, 2000.
First, I would like to repeat the December announcement with budgetary
information in detail. The approval was for Phase 1 of 1,335 Oku Yen of
the total project cost of 1,890 Oku Yen. The JFY2001 budget includes
a first-year purchase commitment of 195.94 Oku Yen while the actual
cash to be spent before the end of JFY2001 is 76.72 Oku Yen. In Japan,
the construction budget does not include personal salaries of the people
involved at JAERI or KEK. Note that Oku = 100 millions.
In early January our two funding agencies, STA and Monbu-sho, merged
together to form one agency, called Monka-sho (I do not know an official
English name of this new agency at this point). Before this merger, KEK
and all national universities were in one Division at Monbu-sho. Now,
KEK and JAERI are in one Division, whereas the universities are in a
separate Division. For our project, thus, a new system is advantageous.
Local governments, both Ibaraki Prefecture and Tokai Village, have
been working actively for our project. The Ibaraki Prefecture, which
includes both the areas of JAERI and KEK, appealed the importance of our
project to the Prime Minister and other important ministers in the fall of
2000. In addition, interactions between the project team and the local
governmentshave been very strong these days. The Tokai Village formed a
special committee to discuss our project. In addition, local inhabitants
in Tokaivisited KEK to study accelerators (five tours to KEK in November,
for example).
The project team is presently discussing a new organization of the team
in order to proceed into the construction phase. I will report the result
of these discussions in the next issue of the Newsletter. Many issues exist
but one that I would like to consider this time is how to include
international voices/opinions/proposals effectively into this project.
A new user group was formed recently. It is an industry-based neutron
scattering group. Over 100 people signed as members of this new user group.
Now, we would like to give a NICKNAME to this project. We are thus
calling for your submissions. The winner will receive a gift from us.
The deadline is February 15. Suggestions from abroad are very welcome.
Send your idea on the nickname together with a brief description of the
reason behind it to aisyo at linac.tokai.jaeri.go.jp
As reported before, construction of the initial part of the Linac is
already in progress. The project team is moving toward construction of both
Linac and synchrotron. To remind you, the components that are included in
the approved Phase 1 are: 1) 400 MeV Linac (normal conducting), 2) 3 GeV
Proton Synchrotron (PS) at 1 MW, 3) 50 GeV PS at 0.75 MW, 4) major part of
the 3 GeV neutron/meson facility, and 5) a portion of the 50 GeV experimental
facility.
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2. Activities of the Accelerator Development Group
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by Yoshishige YAMAZAKI
The 60-MeV linac, which will be the front end of the Joint Project
linac, is under construction at KEK. Although this is mainly funded by the
1998 supplementary budget for KEK, the present effort for this linac is a
joint project between JAERI and KEK. The 60-MeV linac comprises a volume
production negative hydrogen ion source, a low-energy beam transport
(LEBT), a 3-MeV RFQ linac, a medium-energy beam transport (MEBT), a 50-
MeV drift-tube linac (DTL), and a 60-MeV separated DTL. The RFQ linac is
field-stabilized by pi-mode stabilizing loops (PISL) invented for the Joint
Project linac. This has already been installed and aligned and is ready
for the beam commissioning. Since PISL will be also used for the SNS, the
results of the commissioning, which will start in March, should be very
informative for the world-wide high intensity proton accelerator community.
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3. Recent Activities of Facilities Construction Group
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by Yo-ichi AKUTSU
The cost of the major part of the facilities (Linac, 3 GeV Synchrotron,
L3BT(Linac-to-3GeV ring Beam Transport line), 3NBT(3GeV ring-to-Neutron
facility Beam Transport line), and Materials and Science facility
(Neutron-Meson facility)) has been approximately estimated based on the
latest requested specifications. There is a large discrepancy between the
estimated cost and the planned budget. Cost reduction is necessary in each
facility and we will plan to complete the total scheme design by the end of
March 2001. The size of the site for this project is approximately 1/3 of
that of all existing JAERI facilities at the Tokai site and it is recognized
that construction of new facilities will have a large effect on the existing
facilities. Therefore, not only the accelerator arrangement that gives higher
performance to this new project, but also the ideal planning of the whole
site is being studied in consideration of the existing buildings and
facilities such as utilities.
We also studied the temporary facilities necessary to construct the
facilities, such as a temporary road in the site, a temporary bridge
across the Shin River and a dirt dump, and so on.
The construction process of the Linac, which is the first stage of
this project, has been discussed. We determined that three tasks should be
completed prior to commencement of the first construction. These are to
remove obstacles such as the Second boiler building, to fell trees in the
reserved forest, and to construct a temporary bridge across the Shin River
that will be a transport route for excavated dirt. The design for rebuilding
the Second boiler building has been started. To compensate for felling trees
in the reserved forest, we have developed a basic policy to replant in the
developed area after completion of the construction, and will consult the
authorities, who are specialists of conservation of nature recommended by
the Ibaraki prefecture, about the basic policy.
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4. Report from the Accelerator Driven Transmutation (ADS)
Experimental Facility Group
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by Yujiro IKEDA
The initial loading of Pb-Bi into the loop was made and the
circulation of Pb-Bi in the loop under 350oC was realized at the factory
test. The loop has been installed at JAERI and various tests of the
fundamental interaction of the Pb-Bi flow with structural materials in
terms of compatibility, i.e., corrosion, erosion, etc., has been scheduled.
Safety analysis for accidents was carried out for the ADS physics
experimental facility. Also, a preliminary analysis was performed on
responses of reactor power monitor during the pulsed mode operation.
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5. Report from the Safety Analysis Group
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by Nobuo SASAMOTO
Most of our efforts were focused on shielding design calculations for
the linac and the 3 GeV ring, such as radiation streaming through labyrinths,
determination of the local shield at the scraper region, and effectiveness
of the sub-tunnel to protect accelerator equipment from radiation damage.
In order to investigate scenarios of drainage of activated cooling
water and of ventilation of activated air, we made activation calculations for
water and air. For the activation calculations, a hadron transport code was
used to obtain the flux of secondary neutrons and protons. Then the flux
was multiplied by the activation cross sections of the nuclides composing
water and air, to obtain each total radioactivity and radioactivity
concentration. Detailed examination is now in progress to compare the
calculated values with the regulation values. Based on the calculated
radioactivity of air, investigations were made for ventilation frequency,
time to be required for permission of entering the accelerator tunnels, and
location and height of stacks. Also, the calculated radioactivity of cooling
water was used for investigation of capacities of disposal tanks and dilution
tanks.
The effective dose to the public was estimated due to soil and ground
water activated by radiation from the facility through thick shield walls.
At present, because detailed information on ground water behaviour is not
available, overly conservative assumptions on irradiation conditions and
ground water route to the site boundary had to be employed. The estimation
reveals that the annual dose is well below regulation value for uncontrolled
ground water of 10 uSv/y.
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6. Report on the Nuclear and Particle Physics Facility
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by Jun IMAZATO
An experimental hall for the 50 GeV slowly extracted beam is now being
designed. The full size of the hall shall accommodate three primary proton
beam lines : two high intensity lines, A and B, for secondary beam production
and one low intensity line, C for primary beam experiment. There will be two
production target stations on Line A and one station on Line B providing
secondary kaon and pion beams to several experimental areas. However,
because of very limited budget foreseen for the moment for the 50 GeV
facilities, we will be forced to start with the first phase construction
of about half-size of the experimental hall . In the beginning it is very
probable that there will be only one primary line, one target station and a
few secondary channels. The construction of the building shall start in 2004
and be completed in 2006. The fabrication and installation of beam line
elements will be in 2005 and 2006.
In designing the hall we keep the original full building width and
crane span of 60m, so that the elongation of the hall is very easy. Under
the given boundary condition of floor area we will keep the possibility to
layout as many beam lines as possible, although the main part of radiation
shielding surrounding the beam lines should be cast concrete wall and it
limits flexibility of channel layout to a large extent. The details of
secondary channel design and installation priority will be determined based
on concrete experimental proposals or letters of intent, which will be called
for soon. Active participation of users not only in experiments but also
contribution to facility (beam line) design and construction are welcome.
The information on current channel layout etc. will be posted on the web at
http://psux1.kek.jp/~kekpsbcg/jhf/k-arena/k-hall-a.pdf
The neutrino beams emitted toward Super Kamiokande by means of a
fast extracted proton beam will be also a major purpose of our 50 GeV
facility. A beam line system which will be able to provide a wide band,
narrow band as well as an off-axis beam is now being designed.
The construction of the facility will be conducted by Physics Division
III of the Institute of Particle and Nuclear Studies, KEK, which is now
running experiments at the KEK 12 GeV synchrotron. Several subgroups of the
division are now working on R&D of high-intensity beam elements such as a
production target and beam monitors. In these areas also, international
co-operation will become important.
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7. Report from the Muon Science Group
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by Yasuhiro MIYAKE
Since early in the year 2000, a muon science working group meeting has
been held once a month to discuss how to solve various problems in the muon
facility construction. A design of the vicinity of the production target
is in progress under the following guidelines;
a) In the design of the target containment vessel, a large vacuum box
should be considered. This vacuum vessel should contain the target
itself, upstream beam monitors and downstream beam collimators and
scrapers.
b) It also possibly will contain the first elements of the secondary muon
channels and even perhaps the primary beam elements immediately downstream
of the target. (This design approach allows a possible increase in the
acceptance solid-angle of the secondary channels, and makes the removal
of vacuum seals close to the proton beam and the evacuation of air from
the immediate vicinity of the primary beam easier.)
c) Pillow seals should be adopted as vacuum seals for the close spaces
in the immediate vicinity of the target vacuum chamber.
d) All components in the target area must incorporate a radiation shield up
to a level of 2.5 metres above beam level. All complicated connections
such as power and water will be made at this level, where it is expected
that non radiation hard components such as rubber "O" rings, motors,
conventional cabling etc. may be utilized.
e) Below this level all connections will be hard wired or plumbed and any
mechanical connections rigorously minimized.
The muon science experimental area is planned to be located in the
integrated building of the facility for the materials and life science
study. One muon target will be installed upstream of the neutron target for
the first-phase of the Joint Project. The beam line and facility are
designed to allow the later installation of a 2nd muon target in a more
upstream location. The demand for electricity and cooling water has been
summed up for the first-phase, which includes primary proton beam line,
one muon target and secondary beam lines: a superconducting solenoid decay
muon channel, a dedicated surface muon channel, and an ultra slow muon
channel. The detailed design of the secondary beam channel is underway.
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8. Recent Activity of Neutoron Science Group.
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By Susumu IKEDA
We are developing a cross-flow type mercury target. For several serious
technical problems on this target, R&D works are being carried out under
international collaborations with the Oak Ridge National Laboratory, the
Brook Haven National Laboratory and so on. Three moderators will be
installed at the high luminosity regions above and below the target. Those
are super-critical hydrogen coupled-moderator(s) with an extended
pre-moderator and decoupled hydrogen moderator(s). Detailed neutronics
studies on the moderator with the reflector systems of Pb or Be are carried
out. The final geometry as well as the shape and material for moderators
and reflectors are decided, taking into account the critical requirement
from the neutron spectroscopy.
The Fifteenth Meeting of International Collaboration on Advanced Neutron
Sources (ICANS-XV) was held at Tsukuba International Congress Center,
Epochal Tsukuba, Japan, on Nov. 6-9, 2000. The subtitle of ICANS-XV was
“Neutron Source toward the Next Century”, in order to put emphasis on the
importance of developments for high power accelerators and intense
spallation sources. 92 foreign scientists and 170 Japanese scientists
attended to this meeting and discussed about several important issues of
high intense proton accelerators, MW-class neutron sources, neutron
spectrometers, neutron devices and international collaboration. The neutron
group reported many activities achieved in design works of the Joint project.
The ICANS-XV has provided a good opportunity to exchange information,
knowledge, and experience to the participants, and these exchanges and
discussion will eventually contribute to realize the MW-class spallation
source projects currently planned in the world. After the ICANS-XV, the 2nd
International Workshop on TMR Engineering for Spallation Neutron Source
was held on Nov. 13-15 at Tokai-JAERI, in which engineering issues on Target-
Moderator-Reflector system was discussed in detail on the basis of design
activities for spallation neutron sources.
------------------------------------------------------------------------
9. Conferences and Symposium
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1) Muon Science Symposium 2001
Date/Time: January 26 (Fri.) 13:00 - 27(Sat.) 17:00 , 2001
Place: KEK Seminary Hall in No. 4 Bld. , 1st floor, KEK
Discussion of the current design of the Muon Science Facility and
scientific investigations to be performed in the facility.
2) Seminar on Industrial Application of Neutron,
Date February 23, 2001
Place TBD
This is the first forum for using neutrons for industry use. Neutron
facility of JKJ will put stress on industry use.
3) Meeting on Spallation materials
Date March 21-22, 2001
Place Seminary Hall no.1 in No. 4 Bld., 2nd floor, KEK
---------------------- END of News Letter ------------------------------
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