**Trip Report**

### LHC IRQ Collaboration Meeting

March 9 -- 13, 1998

CERN, Geneva Switzerland

Thomas H. Nicol, Engineer (630) 840-3441

Technical Division / Engineering and Fabrication Department

Fermi National Accelerator Laboratory

March 17, 1998

#### Summary

This was the first in what will likely be a series of meetings between
various LHC collaborators. This meeting focused on triplet magnets and
cryostats, near term R&D, and accelerator physics issues. For myself, it
was my first meeting with our counterparts at KEK and with many of our
contacts at CERN.

Initially I was unsure whether we would be able to arrive at agreements
on some of the more pressing decisions facing definition of the baseline
design, but was pleasantly surprised that we did, in fact, define some
baseline parameters. Most notable for me are the following
accomplishments.

-   We agreed that the baseline cryostat design will use the external
    heat exchanger.

-   Q2a and Q2b will be cryostated as one long assembly. This has been
    assumed, but never so clearly stated.

-   All cryostats will be identical, i.e. all Q1s will be alike, all
    Q3s, etc. (Q1s are *not* like Q3s). This is for the sake of
    interchangeability between interaction regions. This includes the
    cold bore tubes.

-   We reached a consensus with the cryogenics group about what will and
    will not be included in the scope of our work on the external heat
    exchanger test unit. Unfortunately the scope increased.

-   We received confirmation of most pertinent parameters of the KEK
    cold mass, most notably the material and diameter. We also agreed on
    a list of items to be provided to KEK for our cryostat effort.

-   We saw at least the initial correction magnet design for the area
    between Q2a and Q2b.

-   We had a very good meeting with the CERN safety department to
    clarify the requirements of our pressure vessel design and
    documentation.

-   Finally, I had my first introduction to CERN's document control
    system. Eventually, all our work will need to be integrated into
    this system so it was good to get at "heads up".

> As time permitted, we were also able to tour some of the LHC
> facilities. A small group of us toured interaction regions 2 and 8. We
> were able to walk through the LHC magnet assembly hall, and finally I
> looked in on the first thermal test of a 10 meter long LHC dipole in
> process to determine the functionality of the 4.5 thermal screen.
>
> I will look back on this trip with many good feelings about the
> progress we made toward a successful collaboration.

**Trip Report**

### LHC IRQ Collaboration Meeting

March 9 -- 13, 1998

CERN, Geneva Switzerland

Thomas H. Nicol, Engineer (630) 840-3441

Technical Division / Engineering and Fabrication Department

Fermi National Accelerator Laboratory

March 17, 1998

#### Introduction

This was the first in what will likely be a series of meetings between
various LHC collaborators. This meeting focused on triplet magnets and
cryostats, near term R&D, and accelerator physics issues. For myself, it
was my first meeting with our counterparts at KEK and with many of our
contacts at CERN.

Initially I was unsure whether we would be able to arrive at agreements
on some of the more pressing decisions facing definition of the baseline
design, but was pleasantly surprised that we did, in fact, define some
baseline parameters. Most notable for me are the following
accomplishments.

-   We agreed that the baseline cryostat design will use the external
    heat exchanger.

-   Q2a and Q2b will be cryostated as one long assembly. This has been
    assumed, but never so clearly stated.

-   All cryostats will be identical, i.e. all Q1s will be alike, all
    Q3s, etc. (Q1s are *not* like Q3s). This is for the sake of
    interchangeability between interaction regions. This includes the
    cold bore tubes.

-   We reached a consensus with the cryogenics group about what will and
    will not be included in the scope of our work on the external heat
    exchanger test unit. Unfortunately the scope increased.

-   We received confirmation of most pertinent parameters of the KEK
    cold mass, most notably the material and diameter. We also agreed on
    a list of items to be provided to KEK for our cryostat effort.

-   We saw at least the initial correction magnet design for the area
    between Q2a and Q2b.

-   We had a very good meeting with the CERN safety department to
    clarify the requirements of our pressure vessel design and
    documentation.

-   Finally, I had my first introduction to CERN's document control
    system. Eventually, all our work will need to be integrated into
    this system so it was good to get at "heads up".

> As time permitted, we were also able to tour some of the LHC
> facilities. A small group of us toured interaction regions 2 and 8. We
> were able to walk through the LHC magnet assembly hall, and finally I
> looked in on the first thermal test of a 10 meter long LHC dipole in
> process to determine the functionality of the 4.5 thermal screen.
>
> I will look back on this trip with many good feelings about the
> progress we made toward a successful collaboration. What follows is a
> collection of my thoughts on the week's work.

# Monday, March 9, 1998

**[9:00 am]{.underline}**

***Initial orientation meeting.***

Present: Ranko Ostojic, Gilbert Trinquart (CERN)

Tom Peterson, Jim Kerby, myself (Fermilab)

Jon Zbasnik (LBL)

This was an initial meeting with Ranko to bring us up to speed on the
general status of interaction region activity, changes, etc. since any
of us had seen him last. A few notes follow.

-   There is no real design for the beam position monitors yet for the
    IR. They are thought to be different than those for the arc.

-   The warm to cold transition at the end of magnets is thought to be
    roughly 400 mm long.

-   The "standard" interconnect is 480 -- 500 mm long (depending on
    where you measure). The 500 mm dimension seems to be between vacuum
    vessel flanges. The 480 mm dimension is to some internal reference.

-   There is a compelling reason (according to Ranko) to make all four
    triplets the same from the standpoint of spares and
    interchangeability. Also, there is some thought being given at CERN
    to possibly swapping high and low luminosity IRs after, say five
    years to essentially double the life expectancy of the systems.

-   The only accommodation to slope is the collection pots at the end of
    either Q1 or Q3. We can probably solve this by installing a
    collection volume at both ends of both types of quads. This way,
    their assembly will not tie them to a specific location.

-   We broached the subject (Kerby, Nicol, and Peterson) of separating
    Q2a and Q2b as a means of shortening the assembly, simplifying
    testing, shipping, installation, etc. It is a question primarily of
    lattice design. We concluded that we need to make a specific
    proposal for the amount of the required separation to add an
    interconnect and have it reviewed.

**[14:30]{.underline}**

***Tour of the magnet string test area, SM18.***

Present: Glyn Kirby, Luca Bottura, Rudiger Schmidt, Luigi Serio (CERN)

Tom Peterson, myself (Fermilab)

Jon Zbasnik (LBL)

This was an informal tour of the magnet string test area and magnet test
areas. We received a broad overview of the string test, which is still
in progress. A leak was being repaired during our visit, but the string
test was basically intact. The only viable magnet test stand is
configured for an older style arc dipole. It will be replaced over the
course of the next few months, initially with four new feed boxes which
accommodate the new 15 m long magnets. I was disappointed to find that
the first feed box, which will likely be used for the heat exchanger
test has not arrived yet.

**[17:00]{.underline}**

***Self-guided tour of Building 181, the LHC magnet assembly
building.***

Present: Jim Kerby, Tom Peterson, myself (Fermilab)

Jon Zbasnik (LBL)

Toward the end of the day we walked to the magnet assembly building on
our own. We were able to look freely at the buss assembly areas, yoking
and skinning press, interconnect models, and the first 15 m long
prototype which recently arrived from E. Zanon in Schio, Italy.

# Tuesday, March 10, 1998

**[9:00 am]{.underline}**

***Tour of interaction points 2 and 8.***

Present: Gilbert Trinquart (CERN)

Tom Peterson, myself (Fermilab)

Jon Zbasnik (LBL)

Gilbert Trinquart gave us a very nice tour of interaction points 2 and
8, which presently house the L3 and Delphi detectors respectively. The
LEP tunnel is clearly ready for operation. It is shut down for winter,
but will restart soon. Decommissioning and dismantling will begin in
2000. Civil construction at both these sites for the LHC will be
minimal. We were able to see approximately where four of eight of the IR
systems will be installed.

**[11:30]{.underline}**

***Tour of the lab doing development on RF fingers.***

Present: Gilbert Trinquart, Patrick Lepeule (CERN)

Myself (Fermilab)

Jon Zbasnik (LBL)

At our request, Gilbert Trinquart arranged for Jon Zbasnik and I to meet
the engineer developing the RF fingers, beam screen, and cold bore
bellows systems. The work to date is very impressive. There is a lot of
mechanical connection work required for the cold bore systems, beam tube
differential expansion bellows, cold bore bellows, beam screen insertion
and connection of cooling lines, and the RF sliding joint. We will
follow this closely, especially the bellows and RF joint development to
see how much we can incorporated into the triplet magnets. The triplets
don't required the beam screen.

**[14:30]{.underline}**

***TIS Seminar presented by the CERN Safety Office.***

Present: Maurizio Bona (presenter) (CERN)

JimKerby, myself (Fermilab)

Jon Zbasnik (LBL)

Audience of approximately 50

This was a safety seminar unrelated to our visit, but of great interest
to us. The official title of Dr. Bona's presentation was:

"Safety requirements for the design, fabrication, testing, and
installation at CERN of the structural components of the LHC machine and
experiments."

We were interested to hear what was to be said since it directly affects
all collaborators building pressure equipment of any kind. At present
CERN uses an internal safety code D2 based in largely on the French code
called CODAP. The presentation today was essentially a forum for
announcement of a revised version of D2 being proposed which will
largely simplify the operational approval process without compromising
safety in any way. Essentially the revision recognizes the safety codes
of member states *and* previously accepted codes, including the ASME.

**[16:30]{.underline}**

***Follow-up pressure vessel meeting.***

Present: Maurizio Bona, Tom Taylor, Andrea Catinaccio (CERN)

Jim Kerby, myself (Fermilab)

In a follow-up meeting immediately after the above seminar, Jim and I
were able to address some things specific to our program. In summary, we
can proceed as we have in the past. For non-magnet pressure vessels and
piping, there are two options. First, if the system can be fabricated as
and ASME coded vessel on the outside, that is probably easiest, but not
essential. Second, for vessels or systems built in-house, we will
continue to design, specify, manufacture, and test to the intent of the
ASME code and obtain a Fermilab "silver sticker". In parallel, we will
keep our CERN collaborators apprised of the ongoing status and provide
them the opportunity to comment, revise, etc. In this way, approval for
operation at CERN will be greatly expedited. This latter scenario is
likely the model we will use in fabricating the external heat exchanger
although we may investigate having it fabricated outside as an ASME
coded system.

For magnets, which are by CERN's recent definition, not pressure
vessels, again we will continue our current practices of design,
specification, material certification, sample testing, weld
documentation, etc. keeping CERN apprised of all steps in the process.

In short, we are relieved by what we learned today about the future
direction of pressure vessel certification at CERN and feel very much
like we can abide by their requirements without significantly altering
our current practices.

# Wednesday, March 11, 1998

**[9:00 am through 18:30]{.underline}**

***Presentations by CERN, Fermilab, KEK.***

Present: (CERN)

(Fermilab)

(BNL)

(LBL)

(KEK)

This was a meeting meant to bring all members of the collaboration (who
were present) up to speed on the status of work in progress, test
results, near term plans, etc. of fellow collaborators. See the attached
agenda. Tom Taylor and Ranko Ostojic delivered an overview on the
present status of work at CERN. This was followed by detailed report by
Mike Lamm (Fermilab/CERN) on the present quadrupole magnets being built
at Oxford. Mr. A. Yamamoto gave overview of the work at KEK, followed by
several detailed reports from others from KEK. Jim Strait and Sasha
Zlobin reported on the status of work at Fermilab followed by detailed
reports by Tom Peterson and myself. Finally, Steve Peggs summarized the
accelerator physics aspects of the collaboration followed by detailed
reports by Fulvia Pilat (BNL) and Jim Holt (Fermilab).

This was a long, but valuable meeting. Of special interest to me were
the reports from KEK. Until this meeting I had really no insight into
their current work or future plans. It concerns Fermilab due to our plan
to cryostat all LHC cold masses fabricated at KEK. There are two more
related meetings tomorrow. One with the CERN feedbox group to discuss
the requirements for our external heat exchanger test and another with
KEK to work out the details of mechanical interfaces relevant to
cryostating and magnet measurements.

# Thursday, March 12, 1998

**[09:00]{.underline}**

***Heat exchanger test unit connection meeting.***

Present: Vladislav Benda, Bruno Vullierme, Rob van Weelderen (CERN)

Tom Peterson, myself (Fermilab)

This meeting was meant to explore the interface requirements,
responsibilities, system capacities, etc. for us to install the LHC IRQ
cryostat heat exchanger test unit on a test stand at CERN. This is not a
new requirement, but this trip represented our first opportunity to
discuss it first hand with the responsible parties at CERN. Our original
thought was that we build the test hardware at Fermilab and ship it to
CERN for incorporation in one of their LHC test stands and for us to
take advantage of their data acquisition, controls, etc. We need to
install it at CERN due to the high pumping capacity required -- much
higher than we have available at Fermilab. Besides, it exercises our
ability to follow CERN's pressure vessel code requirements and helps
establish a presence at CERN.

It turns out that the test stand will not be complete any time soon.
Rather it will work out best for us to attach our device to supply stubs
which will eventually feed their test units. In order for this to work
we need to supply the following. A heat exchanger required on the supply
side can be borrowed from CERN.

-   Complete heat exchanger test unit (four modules plus turnaround).

-   Complete data acquisition system.

-   Heater supply and controls.

-   Supply valves and phase separator.

-   Turbo pump for the insulating vacuum (roughing pump is available).

-   Connecting piping for the cryogenics and insulating vacuum.

The best guess for a time slot is approximately one year from now --
after the shutdown next year. Only then will the supply header from
which the supplies emerge be compete. Our original goal was to ship the
device and test it this calendar year. The schedule at CERN gives us
little more time, but we have more work to do also.

**[14:00]{.underline}**

***CERN, Fermilab, and KEK structural interface meeting.***

Present: Tom Taylor, Ranko Ostojic, Glyn Kirby, Miko Karppinen,

> Lynn Evans Peter Steivers (CERN)

Mike Lamm, Jim Kerby, Jim Strait, Sasha Zlobin, myself (Fermilab)

Jon Zbasnik (LBL)

All (KEK)

This was a meeting meant to clarify any outstanding issues with respect
to mechanical interfaces between CERN, Fermilab, and KEK. It was lead
primarily by Tom Taylor. The first statement was an establishment of the
external heat exchanger as the baseline design. That opens the
possibility to decrease the diameter of the cooling holes in the iron
yoke for both magnet designs. They are presently 60 mm which was driven
by the need to have the heat exchanger internal to the cold mass. Tom
Peterson estimates that the 4 -- 60 mm holes can be reduced to 45 mm. We
also discussed beam tube sizes, materials, coatings, etc. This is still
unsettled, but we will likely use a stainless steel beam tube, copper
plated. We may want to consider adding features in the collar poles to
facilitate insertion of the beam tube in to the magnet after collaring
such that it remains centered and doesn't scrape the coil during
insertion.

We also discussed the possibility of separating Q2a and Q2b. This is
very controversial from the lattice standpoint and looks to me like it
simply won't happen. We will have to count on making Q2a and Q2b
separately then welding them together as one rigid assembly. As part of
this discussion we heard a brief presentation by Miko Karppinen on the
correction coil pack inserted between Q2a and Q2b. The present design is
350 mm OD, 700 mm long.

As far as communications between Fermilab and KEK, we need to specify to
KEK the desired locations for alignment fiducials on the cold mass.
Their position will be influenced by the details of the suspension
system connection. We also need to let them know the details of the end
plate weld prep for welding of the cold mass end domes at Fermilab.

**[17:00]{.underline}**

***Introductory meeting on CERN's engineering data management system
(EDMS).***

Present: Christoph Eck CERN

Myself (Fermilab)

Christoph Eck coincidentally visited Fermilab last week prior to my
visit to CERN. He is a computing manager in some part responsible for
mechanical engineering CAD and analysis. As such he is also involved in
their new EDMS, old CDD (CERN drawing directory), evaluation and support
of new software, etc. Since our work on LHC will ultimately require us
to interact with their drawing management, I just wanted to make the
connection with Mr. Eck at CERN. What I managed to assimilate was small
other than to learn of the web site for their EDMS (called CEDAR):

(<http://www.cern.ch/cedar/welcome.html>)

At the moment the EDMS which is a database of pointers to document data
is not capable of pointing to sites outside CERN, but this is still a
new product for CERN. More will develop from this contact in the future.

# Friday, March 13, 1998

**[09:00]{.underline}**

***Engineering data management system (EDMS) and the LHC.***

Present: Thomas Pettersson, Peter Rohmig (CERN)

Myself (Fermilab)

Mr. Pettersson is the person in CERN's information management division
responsible for implementing engineering document control from the
software standpoint. Peter Rohmig is in the LHC division and is charged
with implementing it in the short straight section (SSS) group. The
generic engineering document management system (EDMS) is implemented in
a framework called project breakdown structure (PBS). As many things at
CERN, PBS is accessed via a web interface. Via this interface, drawings,
specifications, and documentation of nearly any kind associated with
project management can be browsed, printed, copied, etc. It differs
slightly from what I learned earlier from Christoph Eck in the sense
that it seems that the current drawing directory (CDD) isn't actually
being replaced, but rather serves as part of the over PBS. CDD is only
meant to store drawings and as such is not useful for text documents,
spreadsheets, etc. All, however are accessible through the web interface
to PBS.

I received a crash course in navigating PBS, but will need to sit down
with it on my own to learn its finer points. At the moment, only SSS
documents are being handled routinely. Others parts of the LHC project
will follow.

Both Petterson and Rohmig agree that the most difficult aspect of
implementing the EDMS is a cultural one. People are reluctant to accept
this technology, preferring their currently followed practices. This is
as I would have guessed it to be. The benefit of this new this new
culture is not obvious to people at all levels, yet it relies on people
at all levels for it to be successful. It will be interesting to see how
it goes. As an aside, CERN is in the process of evaluating new CAD
modeling software. *Euclid*, the program in use since the early to mid
1980s is being totally rewritten, forcing new file formats. Mr.
Pettersson expects a decision to be made by 2001. They are waiting due
to the desire not to lose the ability to access LEP drawings at least
until it is decommissioned.

**[11:00 and 15:30]{.underline}**

***LHC cryostat support status and the cryostat thermal model (CTM).***

Present: Vittorio Parma, Christine Darve (CERN)

Myself (Fermilab)

I met both Vittorio and Christine at the Cryogenic Engineering
Conference last July in Portland and took this opportunity to see them
both. Vittorio is responsible for development and testing support posts
for all LHC magnets. He showed me around their assembly building where
supports are undergoing fatigue and creep testing. They seem to adopted
a support post design utilizing pre-preg cloth layups. The current
evaluations are meant to test the overall structure and the heat
intercept attachments respectively. Christine is currently testing one
of the latest 10 meter long magnets to evaluate the effectiveness of the
4.5K thermal screen. They are still undecided whether to fully implement
the screen or to rely on multi-layer insulation around the cold mass to
limit heat leak to 1.9K. The test was just started this week. Results
are hoped for in time for presentation at the International Cryogenic
Engineering Conference this summer.

**[14:00]{.underline}**

***Close-out meeting.***

Present: (CERN)

(Fermilab)

(BNL)

(LBL)

(KEK)

Jim Kerby presented a summary of the week's work from notes collected
from each of the sub-groups. My impression was that we had a very
successful week. We made progress toward definition of the baseline,
came to several agreements on may of the integration issues facing CERN,
Fermilab, Brookhaven, LBL, and KEK. There is much to do over the course
of the next few years.

**Trip Report**

### LHC IRQ Collaboration Meeting

March 9 -- 13, 1998

CERN, Geneva Switzerland

Thomas H. Nicol, Engineer (630) 840-3441

Technical Division / Engineering and Fabrication Department

Fermi National Accelerator Laboratory

March 17, 1998

+-----------------------------------+-----------------------------------+
| ## Contacts                       |                                   |
+-----------------------------------+-----------------------------------+
| # Name                            | # Affiliation                     |
+-----------------------------------+-----------------------------------+
| Benda, Vladislav                  | CERN                              |
+-----------------------------------+-----------------------------------+
| Bona, Maurizio                    | CERN                              |
+-----------------------------------+-----------------------------------+
| Bottura, Luca                     | CERN                              |
+-----------------------------------+-----------------------------------+
| Catinnacio, Andrea                | CERN                              |
+-----------------------------------+-----------------------------------+
| Darve, Christine                  | CERN                              |
+-----------------------------------+-----------------------------------+
| Eck, Christoph                    | CERN                              |
+-----------------------------------+-----------------------------------+
| Evans, Lynn                       | CERN                              |
+-----------------------------------+-----------------------------------+
| Karppinen, Miko                   | CERN                              |
+-----------------------------------+-----------------------------------+
| Kirby, Glyn                       | CERN                              |
+-----------------------------------+-----------------------------------+
| Lebrun, Phillipe                  | CERN                              |
+-----------------------------------+-----------------------------------+
| Lepeule, Patrick                  | CERN                              |
+-----------------------------------+-----------------------------------+
| Ostojic, Ranko                    | CERN                              |
+-----------------------------------+-----------------------------------+
| Parma, Vittorio                   | CERN                              |
+-----------------------------------+-----------------------------------+
| Pettersson, Thomas                | CERN                              |
+-----------------------------------+-----------------------------------+
| Rohmig, Peter                     | CERN                              |
+-----------------------------------+-----------------------------------+
| Schmidt, Rudiger                  | CERN                              |
+-----------------------------------+-----------------------------------+
| Serio, Luigi                      | CERN                              |
+-----------------------------------+-----------------------------------+
| Taylor, Tom                       | CERN                              |
+-----------------------------------+-----------------------------------+
| Trinquart, Gilbert                | CERN                              |
+-----------------------------------+-----------------------------------+
| van Weelderen, Rob                | CERN                              |
+-----------------------------------+-----------------------------------+
| Vullierme, Bruno                  | CERN                              |
+-----------------------------------+-----------------------------------+
| Williams, Lloyd                   | CERN                              |
+-----------------------------------+-----------------------------------+
|                                   |                                   |
+-----------------------------------+-----------------------------------+
| Peggs, Steve                      | BNL                               |
+-----------------------------------+-----------------------------------+
| Pilat, Fulvia                     | BNL                               |
+-----------------------------------+-----------------------------------+
|                                   |                                   |
+-----------------------------------+-----------------------------------+
| Lamm, Mike                        | Fermilab at CERN                  |
+-----------------------------------+-----------------------------------+
|                                   |                                   |
+-----------------------------------+-----------------------------------+
| Zbasnik,Jon                       | LBL                               |
+-----------------------------------+-----------------------------------+
|                                   |                                   |
+-----------------------------------+-----------------------------------+
| Kimura, Norihino                  | KEK                               |
+-----------------------------------+-----------------------------------+
| Nakamoto, Tatsushi                | KEK                               |
+-----------------------------------+-----------------------------------+
| Ogitsu, Toru                      | KEK                               |
+-----------------------------------+-----------------------------------+
| Ohhata, Hirokatsu                 | KEK                               |
+-----------------------------------+-----------------------------------+
| Ohuchi, Norihito                  | KEK                               |
+-----------------------------------+-----------------------------------+
| Shitomi, Taka                     | KEK                               |
+-----------------------------------+-----------------------------------+
| Tanaka, Kenichi                   | KEK                               |
+-----------------------------------+-----------------------------------+
| Terashima, Akio                   | KEK                               |
+-----------------------------------+-----------------------------------+
| Tsuchiya, Kiyosumi                | KEK                               |
+-----------------------------------+-----------------------------------+
| Yamamoto, Akira                   | KEK                               |
+-----------------------------------+-----------------------------------+

**Trip Report**

### LHC IRQ Collaboration Meeting

##### Itinerary

Thomas H. Nicol, Engineer (630) 840-3441

Technical Division / Engineering and Fabrication Department

Fermi National Accelerator Laboratory

CERN, Geneva Switzerland, March 9-13, 1998