I=nteraction PointEvents and Happenings

in the SLAC CommunityNovember 1996 Vol. 7, No. 8

How It Takes at Least ThreeVillages to Raise a Cavity

Story of the PEP-IIRF Cavity

by Bob Rimmer, Matt Allen andHeinz Schwarz

THIS IS THE STORY of the devel-opment of the radio-frequency (rf)cavity for the B-factory project,also known as PEP-II. The rf cavi-ties are structures that transformmicrowave power (from hugemegawatt klystron amplifiers),into accelerating voltage to main-tain the energy of the electronsand positrons that are collidedtogether in the physics experiments.

It soon became apparent that apowerful and reliable rf systemwould be needed to maintain theextremely high beam power in thenew machine. When a beam goesthrough a cavity it causes it to"ring" electrically much as a largebell rings when struck. A cavitycan ring in many ways or modesand only one of these is useful toaccelerate the beam; all of the oth-ers must be eliminated to allowthe rf system to do its job and tokeep the beams stable. For PEP-IIthis requires a new kind of cavitydesign to suppress these higher-order modes (HOMs) far morestrongly than any machine cur-rently operating, without signifi-cantly reducing the operating effi-ciency, otherwise construction andoperating costs would beincreased.

As the B-factory project gath-ered momentum key personnel(cont'd. on page 6)

by Ilse Vinson

SCS PLANS TO REMOVE the ES9000 mainframe that runs VM by the endof 1997. To do that, we will phase out the remaining services on VM.After March 1, 1997, you will need to justify continued use of VM asdescribed on the Web VM Migration page at http://www.slac.stanford.edu/comp/vm/vmmigr.html. (To access a Web page on VM enter the com-mands: web followed by go page-location, e.g., go http://www.slac.stanford.edu/compv/v/vmmigr.html) Because some business applicationswon't be converted by then, Business Services Division account ($BS)users may continue VM use without prior approval after this date.

Several classes are offered at SLAC to help VM users move over toreplacement applications. Consult the Web page at http://www.slac.stanford.edu/comp/edu/calendar.html for the schedule of the classes BeyondVM and Eudora-Pro, the mail system replacement on the Mac and PC.

If you still use VM, please fill out the VM Migration Questionnaire atthe Web URL http://www.slac.stanford.edu/comp/vm/vmques.html to assistthe VM Migration Committee in making the necessary decisions leadingup to the SLACVM shutdown.

The proposed implementation dates for SLAC Business InformationSystems (BIS) are as follows:

Budget application 2/1/97 Purchasing Pilot 7/1/97HRMS & Payroll 7/1/97 Financials application* 10/1/97Purchasing site-wide 10/1/97

People are responsible for moving their own applications. The WebVM Migration page describes replacement plans for many applications.For example, the SLAC Library data will move to UNIX on March 1,1997, and ELDREQ will be replaced in October 1997 by the PeopleSoftPurchase module. SCS is in the process of contacting all ELDREQ users.If you would like to know the migration plan for an application thatyou do not see on this page or want more information than is given,contact the application owner.

Visit the Web VM Migration page for further information aboutreplacement resources, and look for further updates in future issues ofthe Interaction Point. If you have any questions or concerns that are notaddressed by the VM Migration Web page or our classes, please contactthe Help Desk at help@slac.stanford.edu or x4357. If you wish to have anSCS representative meet with your group to discuss specific require-ments, call the Help Desk to schedule an appointment.

*Includes: Project Costing, Accounts Receivable, Accounts Payable, General Ledger, AssetManagement and Stores Inventory.

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Techpubs to Give Second Poster WorkshopTHE SECOND IN A SERIES of three workshops offered by the TechnicalPublications Department on making posters for scientific conferences isscheduled for November 15, at 3 p.m. in SCS Conference Rooms A&B.This workshop will focus on using Adobe Illustrator (on Mac or PC) tocreate large-scale printouts that can be used as conference posters. Theworkshop will demonstrate how to use an established suite of postertemplates developed especially for SLAC authors and a few basic posi-tioning and sizing commands to create one-piece posters that are visual-ly compelling and easy to read.

The first workshop in the series (held in October) demonstrated basicdesign and paste-up techniques for building posters "the old fashionedway" without using graphics software. Notes from the workshop areavailable on the WWW as part of the TechPubs Help Pages, at htt://www.slac.stanford.edu/grp/techpubs/help/graphics/posters/basics.html. Thethird workshop in the series (not yet scheduled) will demonstrate usingMicrosoft PowerPoint to build posters.

The poster workshops are coordinated and led by Terry Anderson(Computer Graphics) and Maria Breaux (Information and DocumentTechnology).

Like It or Not

Personal Info Available Electronicallyby Diana Gregory

ANYONE LISTENING to the radioor reading a newspaper in mid-September probably heard aboutthe Lexis-Nexis database. You alsomay have heard about it from awidely distributed e-mail message.

The available data in the P-Trakdatabase includes current and for-mer addresses, birth dates, andeven maiden names. It is suppliedby Lexis-Nexis to lawyers andlaw-enforcement officials trying totrack down witnesses, debtors, orheirs, but the information isapparently available to anyonewilling to pay a search fee of upto $100. The database service hasbeen operating since June.

Lexis-Nexis officials have saidthat searchers will not be able tofind social security numbers,mothers' maiden names, credit ormedical history, or personal finan-cial data as the anonymous e-mailmessages were accusing. Lexis didsay that the service initially pro-vided social security numbers, butthat feature was dropped in June

after earlier complaints-but alsonoted that social security numbersare "available on the Internet froma number of sources."

To have your name removedfrom P-Trak, write to Lexis-Nexis,PO Box 933, Dayton, OH 45401-0933or FAX to (513) 865-1930. Lexis-Nexis has said it will honor indi-vidual requests to have namesremoved. The deletions, however,may not take place for 60 days,when the database is updated.The number to call for verificationof removal is (513) 865-6800.

Of additional interest to SLAC,home address information isavailable on the Web at http://www.infosource.com. This site callsitself "The Most ComprehensiveDirectory on the Internet," andhas some useful information,including the "people" directory.The problem is that if you listyour home address in the phonebook, it has a link to a map ser-vice, and people can click on thelink and get a map that showsthem exactly where you are living.

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SLAC Represented

DOE Day in OaklandAppeals to Public

THE DEPARTMENT OF ENERGYbecame the focus of attention onOctober 10 when Bay Area labora-tories and the DOE hostedexhibits, entertainment, andprizes for the crowds at CityCenter Plaza in Oakland.

The purpose of the annualevent is to give the general publica glimpse of the many facetswithin the Department of Energy.SLAC was represented by P. A.Moore and Nina Stolar who dis-tributed flyers and advice on sci-ence careers.

"I think DOE Day is a greatway to bring science to the peoplesince several thousand walkedthrough the Plaza during theperiod we were there," said Stolar.

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THE FOLLOWING PEOPLE joinedSLAC in September and earlyOctober: Evgeniy Antokhin, BaBar;Brenton Baugh, ARD-A; Chih-Hsiang Cheng, Exp. Group B; CarolChao, SSRL; Nels Christensen,MFD; Mark Convery, Exp. Group B;Philip Davis, Tech Info Services;Sergey Ganzhur, BaBar; JosephGrandov, PEP-II B Factory; KazumiHasuko, SLD; Heino Henke, ARD-B; Donald Hughes, Klystron; IrwinLee, Exp. Group E; Cecile Limborg,SSRL; Stephan Mikhailov, BaBar;Masahiro Morii, Exp. Group C;Steven Myers, Exp. Group A;Benoit Parise, MFD; Ann Redfield,Tech Info Services; Victor Rey,Klystron; Yue Yang, SSRL

1996 Summer Institute Only a Memoryby Jennifer Chan and Lilian DePorcel

THE END OF SUMMER broughttogether a diverse and interna-tional group of young and seniorphysicists to study how QCD, thetheory of strong interactions, isbeing probed at present-day col-liders. The SLAC SummerInstitute, held from August 19-30,focused on a series of lectures cov-ering in-depth aspects of thestrong interaction.

Gathered in the auditorium,approximately 240 participantsfrom 16 countries displayed deepattention as James D. (Bj) Bjorkenopened the school with a lectureaddressing QCD questions, chal-lenges, and dilemmas. DavisonSoper (Oregon) followed with aseries on QCD perturbation theory.Adam Falk, an ex-SLAC theoristnow at Johns Hopkins University,lectured on "Heavy QuarkExpansion of QCD." The series onQCD studies in hadron-hadroncollisions was given by MichaelAlbrow from Fermilab. Returningfor an encore after a three-yearabsence, TomDeGrand eloquentlyaddressed lattice gauge theory.Phil Burrows, from MIT and awell-known face in the SLD/SLACcommunity, captured the stu-dents' interest with his livelyseries on precision tests of QCD ine+e- annihilations. The lectures onthe "Search for Glueballs" weregiven by Walter Toki, also an ex-SLACer, currently at ColoradoState University. The second weekof the school began with WesleySmith's (Wisconsin) lectures onQCD Studies in electron-protoncollisions, followed by Al Mueller(Columbia University) on "Low xPhenomena." The school closedwith Jim Wiss' (Illinois) talking onQCD in heavy quark productionand decay.

During the School, stimulatingafternoon discussion sessions,spirited by our local provocateurs,

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took place in the Orange Roomgiving students an opportunity toprobe topics that most interestedthem. The Institute concludedwith a three-day topical confer-ence on recent developments intheory and experiment.

The Institute was not onlyabout physics, but also was anopportunity to tour experimentalfacilities and to learn about on-going research projects. This yearmore participants than eversigned up for the annual tour ofthe Lick Observatory, sparked bycuriosity and interest in the recentdiscovery of new planets beyondthe solar system. Besides gazing atthe stars, the moon, and Jupiter,participants were treated to aninformal symposium covering theinstrumentation and spectrographused for the planet discoveries.

The Summer Institute was astrong attraction for young physi-cists from around the world whoeagerly learned how QCD isexplored at current colliders. TheInstitute was not all hard work,however, as the participantsenjoyed dinners in the Cafeteriapicnic grounds, a popular week-end outing, and an exciting soccergame with the unbeatable SLACteam.

Photographs that capture theessence of the 1996 SummerInstitute are displayed in theCentral Lab outside room 240.

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Visitor Center, Klystron Exhibits StrAN OPEN HOUSE for campus representa-tives, local business leaders, and mayorsand city managers was held at the newSLAC Visitor Center on Wednesdayevening October 2. The purpose of thesocial event was to introduce our neigh-bors to the SLAC klystron exhibit, devel-oped by George Caryotakis, and theVisitor Center, developed by Helen Quinn.

Director Burton Richter welcomed thegroup of approximately 150 guests with ashort talk in the auditorium, followed bycomments from Associate Director ArthurBienenstock. Staff from the DOE OaklandOperations Office also visited, as well as Glenn Tenney recently reired from Plantreporters from the Palo Alto Weekly and Engineering, congratulates Adelethe Menlo Park Almanac. Panofsky on her display of the

Lauren Friedman, at SLAC with her Paleoparadoxia.parents, enjoyed the talks. "They helped

. . . . . . . ·.1

me to see where physics is heading in thenext few years." William Friedman,Chairman and CEO of Allergene, wasinterested in details of experimentsexplained by Stanley Brodsky. Other sci-entists who provided explanations aboutthe exhibits were Michael Peskin, MattAllen, and Karl Brown. Guests lingeredover the displays until closing time.

Above: In the Visitor Center a group cters around SLAC theorist Michael Pe,as he creates a particle collision withbare hands. (L to R) Lauren FriedmarWilliam Friedman, Kathryn Henniss (7Pubs), David Knight, and Eleanor Kni

Theoretical physicist Stan Brodsky.

Anatoly Krasnykh, left, and Greg Loeenjoy the Visitor Center exhibits.

Bertha and Max Dresden, visiting Right: Pief Panofsky, SLAC Directorer'hnklr rhft wA/ith ,lin .qtnlqr frnm P ihlin' Fmpriti /c nod a/lrvi/in nhnlnrnw/ .Stfl

V// IUI/ /o IIL VVILI I I VI/ 11 VLVLI I lll I I vilv III I VILA, I-VV tvl v LI

Perry Wilson, accelerator physicist, views the Affairs. Stolar coordinated the activities Physics Department, in discussion w,nrlipCt kls/trnn fnr the Onon Hnl .se Ted Moreno views exhibits.

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Igthen Community Links

Ed Ginzton, left, SLAC and VarianEmeritus, and Richard Taylor, SLACNobel Laureate, deep in conversation.

Jim Turner, DOE Oakland OperationsOffice, views the klystron exhibits withphysicist Matt Allen on his left.

Karl Brown, left, Research Division,and Tom Sege, Varian, catch up onnews.

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PEP-II RF Cavity(cont'd. from page 1)

were drafted from each of theparticipating labs, SLAC, Berkeley(LBNL), and Livermore (LLNL).The team assembled to concen-trate on the rf system drew peoplefrom all three labs and has been aprime example of how this projecthas benefited by close collabora-tion at all levels.

The Berkeley rf contingent,including Glen Lambertson, BobRimmer, and Ferd Voelker, setabout developing a concept forthe B-factory cavity. They addedextra openings or "waveguides"to the body of the cavity, placed toafford the maximum suppressionof the worst unwanted modewhile simultaneously damping allothers to acceptable levels. Theidea was further developed usingcomputer models built at SLAC byKwok Ko, Cho Ng, and RandPendleton, with analytical helpfrom Norman Kroll, and was vali-dated by measurements on a full-size model cavity at Berkeley byBob Rimmer and David Goldberg.

This rf design was so successfulat the first attempt that theemphasis moved on to designinga high-power test model anddeveloping the manufacturingtechnology to be used for the pro-duction run of cavities. JohnHodgson at SLAC performeddetailed 3D finite-element thermaland stress analysis to optimize thecooling scheme and achieve thelowest overall stress in the cavitybody. Long-time SLAC engineerKnut Skarpaas developed the fab-rication plan for the high-powercavities, in which brazed portassemblies are electron-beamwelded into fabricated and elec-troformed bodies. First TomMcCarville and then Curt Belser

and Mark Franks played key rolesin coordinating the R&D at Liver-more. LLNL's Doug Berger devel-oped the deep-penetration e-beamwelding parameters, while ChrisStephanie, also at Livermore,developed a plating process toform thick jackets over the bodywater channels. SLAC's Joe Steiberand Hank Antilles and LLNL'sLarry Cadapan designed the cavi-ty raft assembly while mechanicalengineer Joe Saba and designer AlConstable finished the design ofthe high-power cavity and pro-duced a detailed drawing package.

The high-power tests of a pro-totype cavity were a completesuccess, meeting all of our designgoals and validating both the rfdesign and the production tech-nologies. On this basis and analy-sis of costs the project manage-ment decided to build the cavities

within the three-lab collaboration,under system manager MattAllen, system engineer HeinzSchwarz, and LBNL physicist BobRimmer, with subcontracts to BayArea machine shops and selectindustrial partners.

Once the go-ahead was givento begin production the fun reallystarted. Large materials ordersand service contracts were placedby Ron Antrim from SLAC's pur-chasing department; Livermorebegan producing cavity bodies,and Carl Rago of MFD keptSLAC's shops filled to capacitywith other parts. Port assembliesmachined in industry and brazedat SLAC fitted perfectly into bod-ies prepared at Livermore, thanksto rigorous quality control, over-seen by SLAC's Darren Marsh.Mike Neubauer stepped up

(cont'd. on page 7)

The Interaction Point © 1996, is published by Stanford Linear Accelerator Center. Editor-in-chief, P. A. Moore; Production Editor, VickeeFlynn. Deadline for articles is the first of every month. Items are published on a space-available basis and are subject to edit. Informationon how to write for The Interaction Point is available on the World Wide Web at http://www.slac.stanford.edu/ pubs/slaconly/tip/tip.html.Submissions may be sent electronically to tip@slac.stanford.edu or by SLAC ID mail to TIP, MS 20.Phone 926-4208.

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The first PEP-II rf cavity assembly (photo courtesy Bob Rimmer).

(cont'd. from page 6)to manage production of rfcomponents built at SLAC whileLLNL's Mark Franks continued tooversee the Livermore fabricationand industry contracts for the e-beam welding.

SLAC's Jim Judkins and BobRimmer from Berkeley performedthe final frequency tuning atLivermore and in July this yearthe first production cavity wasflow-balanced by LLNL's EdThomas and delivered to SLAC.Mark Hoyt and Jeff Jones fittedwindow and coupler componentsand HOM loads provided by engi-neers Karen Fant and MikeNeubauer and designer TimMontagne. A new tuner was fittedcourtesy of Heinz Schwarz anddesigner Ed Evans. The cavitywas baked in an oven provided

by Mike Zurawel and Jay Venti ofMFD and installed in the testbunker by Jim Judkins, Alan Hill,Alden Owens and MarcusGorgees. The cavity processedquickly up to full power using acomputer control system puttogether by Alan Hill, and onSeptember 26 satisfied the criteriaof a major project milestone,tracked by the DOE, for a "full rfcavity system integration test,"once again showing that the pro-ject is right on track.

The development of the cavityfrom its earliest inception to thecurrent production status wouldnot have been possible withoutthe help of many more peoplethan it is possible to mention hereby name, but they can all beproud of their contributions whenthe machine comes on line in 1998.

SLAC First US WWWSite, Not FermilabIN THE AUGUST 16 issue ofFermiNews, the front-page head-line reads "Birthplace of theWeb" which one could interpretas meaning that the first US Website was at Fermilab. Not so,according to SLAC experts LesCottrell, Paul Kunz, and JoanWinters.

SLAC was the first Web site inthe US, with a verified date ofDecember 12, 1991, according toRobert Calliou of CERN. Fermilabjoined in June 1992.

Close reading of FermiNewsshows that the newsletter is cred-iting the field of high energyphysics as the impetus for thespread of the Web to the US andon that point we can agree.

Around the Globe with C++C++ IS AN OBJECT ORIENTED programming lan-guage, first released in 1985. At that time, FORTRANwas the programming package used by the scientificcommunity. In 1989, Paul Kunz (Group B) and BillAtwood (Group EK) were among the few SLAC staffwho started learning object oriented programmingto solve a lot of difficulties in maintaining largecode. FORTRAN is still heavily used by physicistsalthough object oriented programming has a largefollowing in the industrial community.

Then BaBar submitted their Technical Design Reportin March 1995 and announced that their softwarewould be based on object oriented programming.Out of over 500 collaborators, less than a dozenknew how to use C++. So, how do you teach techni-cal information to almost 500 people worldwide? Dothey learn it slowly by actually using it, or take acourse? Hands-on training was too difficult to over-see or to pick up the needed skills. So, then how totrain-textbook or workshops by professionals?

It was decided that the best way was to have acourse taught by a physicist for physicists to get theright flavor. Then examples would be directly fromproblems that they were used to dealing with. SinceKunz had been working with C++ for the past 7years, the BaBar Collaboration invited him to designand teach a course, both to teach C++ and to showthat it was the right programming decision to make.Not surprisingly, there was reluctance to move to

C++ due to familiarity with FORTRAN. The firstclass was held at SLAC in 1995 during May-June andmet once aweek for sixweeks. It tookKunz the rest ofeach week toprepare the lec-tures. It can benoted here thatthe lecturenotes have notchanged signifi-cantly since thispreparationXATnQ 1ACD 0 a nOVVW Cd ULULU. I C Paul Kunzquickly fol-lowed up with lectures at Lawrence BerkeleyNational Laboratory and Lawrence LivermoreNational Laboratory, then back for two more SLAClectures. From May through September, 150 physi-cists attended his classes.

BaBar collaborators are not the only onesinterested in learning C++ in this interactive style;over the past year, laboratories worldwide haveinvited Kunz to their locations. To date, over 750physicists from six countries have attended hisweek-long lecture. Kunz, itinerant physicist, is nowa frequent flying teacher.

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Meet the Mechanics

MEET (1 to r) AL MANUEL (Lead Mechanic), RON ANDERSON (MechanicSpecialist), and MIKE SMITH (Journeyman Mechanic) of the Transporta-tion Department. Al will be commemorating 31 years at SLAC onNovember 1; Ron and Mike have been here for a combined total of 38years (almost as long as some of our vehicles). In addition to maintain-ing the DOE fleet of approximately 600 vehicles (trucks, forklifts, mope-ds, electric carts, etc.), they are quite familiar to SLAC train commuters,since they are also the bus drivers who deliver SLACers to and from thePalo Alto train station four times a day.

The current pick-up schedule to and from the train station is as follows:6:45 a.m. & 7:45 a.m. SLAC bus at Palo Alto train station.3:20 p.m.-3:30 p.m. SLAC bus stops at Gate 17, SSRL, ESA, MCC and the

Fire Station.4:45 p.m.-4:50 p.m. SLAC bus stops at Computer Bldg, Bldg 24, and A&E

Bldg.

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