ATOMIC PHYSICS AT ACCELERATORS: MASS SPECTROMETRY

Proceedings of the APAC 2000,

held in Cargese, France, 19-23 September 2000

Edited by

DAVID LUNNEY

CSNSM-IN2P3-Universite de Paris Sud, Orsay, France

GEORGES AUDI

CSNSM-IN2P3-Unil'ersite de Paris Sud, Orsay, France

and

H.-JURGEN KLUGE

GSI, Darmstadt, Germany

Reprinted from Hyperfine Interactions Volume 132, Nos, 1-4 (2001)

KLUWER ACADEMIC PUBLISHERS DORDRECHTI BOSTON I LONDON

A c.I.P. Catalogue record for this book is available from the Library of Congress.

ISBN 978-90-481-5825-6 ISBN 978-94-015-1270-1 (eBook) DOI 10.1007/978-94-015-1270-1

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TABLE OF CONTENTS

D. LUNNEY / Foreword - Organizing APAC2000

Tutorial on aspects of atomic masses (in honor of the 78th birthday of Aaldert Wapstra)

G. AUDI / The Evaluation of Atomic Masses

A. LEPINE-SZILY / Experimental Overview of Mass Measurements

J. M. PEARSON / The Quest for a Microscopic Nuclear Mass Formula

G. SOFF, I. BEDNYAKOV, T. BEIER, F. ERLER, I. A. GOIDENKO, U. D. JENTSCHURA, L. N. LABZOWSKY, A. V. NEFIODOV, G. PLUNIEN, R. SCHUTZHOLD and S. ZSCHOCKE / Etfects of

1-6

7-34

35-57

59-74

QED and Beyond from the Atomic Binding Energy 75-103

S. GORIELY / Nuclear Masses and the r- and p-Processes of Nucleosynthesis 105-114

J. C. HARDY and I. S. TOWNER / Standard-Model Tests with Superal-lowed ,B-Decay: An Important Application of Very Precise Mass Measurements

A. H. WAPSTRA / Memories of Mass Determinations

Mass measurements and nuclear structure

C. N. DAVIDS, P. J. WOODS, J. C. BATCHELDER, C. R. BINGHAM, D. J. BLUMENTHAL, L. T. BROWN, B. C. BUSSE, M. P. CAR­PENTER, L. F. CONTICCHIO, T. DAVINSON, J. DEBOER, S. J. FREEMAN, S. HAMADA, D. J. HENDERSON, R. J. IRVINE, R. V. F. JANSSENS, H. J. MAIER, L. MULLER, R. D. PAGE, H. T. PENTTILA, G. L. POLl, D. SEWERYNIAK, F. SORAMEL, K. S. TOTH, W. B. WALTERS and B. E. ZIMMERMAN / Masses and Proton Separation Energies Obtained from Qa and Qp Measure­ments

M. HUYSE, A. ANDREYEV, K. VAN DE VEL, P. VAN DUPPEN and R. WYSS / Anomalies in the a-Decay Energies and Half-Lives of

115-126

127-131

133-139

Neutron -Deficient Po Isotopes 141-146

F. SARAZIN, H. SAVAJOLS, W. MITTIG, F. NOWACKI, N. A. ORR, Z. REN, P. ROUSSEL-CHOMAZ, G. AUGER, D. BAIBORODIN, A. V. BELOZYOROV, C. BORCEA, E. CAURIER, Z. DLOUHY, A. GILLIBERT, A. S. LALLEMAN, M. LEWITOWICZ, S. M. LUKYANOV, F. DE OLIVEIRA, Y. E. PENIONZHKEVICH, D. RIDIKAS, O. TARASOV, H. SAKURAI and A. DE VISMES / Shape Coexistence and the N = 28 Shell Closure Far from Stability 147-152

E. ROECKL / Decay Experiments on N rv Z nuclei: The role of Masses, Q Values and Separation Energies 153-161

Mass measurements for metrology

R. S. VAN DYCK, JR., S. L. ZAFONTE and P. B. SCHWINBERG / Ultra­Precise Mass Measurements Using the UW-PTMS

S. RAINVILLE, M. P. BRADLEY, I. V. PORTO, J. K. THOMPSON and D. E. PRITCHARD / Precise Measurements of the Masses of Cs, Rb

163-175

and Na - A New Route to the Fine Structure Constant 177-187

A. PAUL, S. ROTTGER, A. ZIMBAL and U. KEYSER / Prompt (n,y) Mass Measurements for the AVOGADRO Project 189-194

G. L. BORCHERT, B. MANIL, D. ANAGNOSTOPOULOS, J. P. EGGER, D. GOTTA, M. HENNEBACH, P. INDELICATO, Y. W. LIU, N. NELMS and L. M. SIMONS / Precision Measurement of the Charged Pion Mass by High Resolution X-Ray Spectroscopy

G. WERTH, H. HAFFNER, H.-J. KLUGE, W. QUINT, T. VALENZUELA and J. VERDU / A Possible New Value for the Electron Mass from g-Factor Measurements on Hydrogen-Like Ions

On-line ion trap mass measurement programs

G. BOLLEN, F. AMES, G. AUm, D. BECK, J. DILLING, O. ENGELS, S. HENRY, F. HERFURTH, A. KELLERBAUER, H.-I. KLUGE, A. KOHL, E. LAMOUR, D. LUNNEY, R. B. MOORE, M. OINO­NEN, C. SCHEIDENBERGER, S. SCHWARZ, G. SIKLER, J. SZE­RYPO, C. WEBER and the ISOLDE Collaboration / Mass Measure-

195-207

209-213

ments on Short-Lived Nuclides with ISOLTRAP 215-222

G. SAVARD, R. C. BARBER, C. BOUDREAU, F. BUCHINGER, J. CAG­GIANO, J. CLARK, J. E. CRAWFORD, H. FUKUTANI, S. GULICK, J. C. HARDY, A. HEINZ, J. K. P. LEE, R. B. MOORE, K. S. SHARMA, J. SCHWARTZ, D. SEWERYNIAK, G. D. SPROUSE and J. VAZ / The Canadian Penning Trap Spectrometer at Argonne

T. FRITIOFF, C. CARLBERG, G. DOUYSSET, R. SCHUCH and I. BERGS­TROM / Recent Progress with the SMILETRAP Penning Mass

223-230

Spectrometer 231-244

On-line mass programs

H. SAVAJOLS / The SPEG Mass Measurement Program at GANIL 245-254

D. S. BRENNER / Mass Measurements at the Wright Nuclear Structure Laboratory 255-263

YU. E. PENIONZHKEVICH / Mass Measurements in Nuclear Reactions 265-273

On-line mass programs using circulating ions

M. CHARTIER, W. MITTIG, G. AUGER, B. BLANK, J. M. CAS AND­HAN, M. CHABERT, J. FERME, L. K. FIFIELD, A. GILLIBERT, A. S. LALLEMAN, A. LEPINE-SZILY, M. LEWITOWICZ, M. MAC CORMICK, M. H. MOSCATELLO, F. DE OLIVEIRA, N. A. ORR, G. POLITI, F. SARAZIN, H. SAVAJOLS, C. SPITAELS, P. VAN ISACKER, A. C. C. VILLARI and M. WIESCHER / The Mass Programme at GANIL Using the CSS2 and CIME Cyclotrons 275-281

YU. A. LITVINOV, F. ATTALLAH, K. BECKERT, F. BOSCH, M. FALCH, B. FRANZKE, H. GEISSEL, M. HAUSMANN, TH. KERSCHER, O. KLEPPER, H.-J. KLUGE, C. KOZHUHAROV, K. E. G. LOBNER, G. MUNZENBERG, F. NOLDEN, YU. N. NOVIKOV, Z. PATYK, W. QUINT, T. RADON, C. SCHEIDENBERGER, M. STECK, L. VERMEEREN and H. WOLLNIK / Schottky Mass Measurements of Cooled Exotic Nuclei 283-289

M. HAUSMANN, J. STADLMANN, F. ATTALLAH, K. BECKERT, P. BEL­LER, F. BOSCH, H. EICKHOFF, M. FALCH, B. FRANCZAK, B. FRANZKE, H. GEISSEL, TH. KERSCHER, O. KLEPPER, H.-J. KLUGE, C. KOZHUHAROV, YU. A. LITVINOV, K. E. G. LOBNER, G. MUNZENBERG, N. NANKOV, F. NOLDEN, yu. N. NOVIKOV, T. OHTSUBO, T. RADON, H. SCHATZ, C. SCHEI­DENBERGER, M. STECK, Z. SUN, H. WEICK and H. WOLLNIK / Isochronous Mass Measurements of Hot Exotic Nuclei

D. LUNNEY, C. MONSANGLANT, G. AUDI, G. BOLLEN, C. BORCEA, H. DOUBRE, C. GAULARD, S. HENRY, M. DE SAINT SIMON, C. THIBAULT, C. TOADER, N. VIEIRA and the ISOLDE Collab­oration / Recent Results on Ne and Mg from the MISTRAL Mass

291-297

Measurement Program at ISOLDE 299-307

Recent mass measurements for nuclear physics

F. HERFURTH, J. DILLING, A. KELLERBAUER, G. AUDI, D. BECK, G. BOLLEN, S. HENRY, H.-J. KLUGE, D. LUNNEY, R. B. MOORE, C. SCHEIDENBERGER, S. SCHWARZ, G. SIKLER, J. SZERYPO and the ISOLDE Collaboration / Towards Shorter-Lived Nuclides in ISOLTRAP Mass Measurements

A. S. LALLEMAN, G. AUGER, W. MITTIG, M. CHABERT, M. CHARTIER, J. FERME, A. GILLIBERT, A. LEPINE-SZILY, M. LEWITOWICZ, M. H. MOSCATELLO, N. A. ORR, G. POLITI, F. SARAZIN, H. SAVAJOLS, P. VAN ISACKER and A. C. C. VILLARI/Mass Measurements of Exotic Nuclei around N = Z = 40 with CSS2

C. WAGEMANS, J. WAGEMANS and G. GOEMINNE / Determination of Atomic Masses and Nuclear Binding Energies via Neutron Induced

309-314

315-322

Reactions 323-329

J. DILLING, G. AUDI, D. BECK, G. BOLLEN, F. HERFURTH, A. KELLER­BAUER, H.-J. KLUGE, D. LUNNEY, R. B. MOORE, C. SCHEI­DENBERGER, S. SCHWARZ, G. SIKLER, J. SZERYPO and the ISOLDE Collaboration / Mass Measurements of 114-124.130Xe with the ISOLTRAP Penning Trap Spectrometer 331-335

S. SCHWARZ, F. AMES, G. AUDI, D. BECK, G. BOLLEN, 1. DILLING, F. HERFURTH, H.-J. KLUGE, A. KELLERBAUER, A. KOHL, D. LUNNEY, R. B. MOORE, H. RAIMBAULT-HARTMANN, C. SCHEIDENBERGER, G. SIKLER and J. SZERYPO / Accurate Mass Determination of Neutron-Deficient Nuclides Close to Z = 82 with ISOLTRAP 337-340

Atomic theory

V. M. SHABAEV, V. A. YEROKHIN, O. M. ZHEREBTSOV, A. N. ARTEM­YEV, M. M. SYSAK and G. SOFF / QED Effects in Heavy Few­Electron Ions

P. INDELICATO, E. LINDROTH, T. BEIER. J. BIERON, A. M. COSTA, I. LINDGREN, 1. P. MARQUES, A.-M. MARTENSON-PENDRILL, M. C. MARTINS, M. A. OURDANE, F. PARENTE, P. PATTE, G. c. RODRIGUES, S. SALOMONSON and J. P. SANTOS / Relativistic Calculations for Trapped Ions

I. BEDNYAKOV, L. LABZOWSKY, G. PLUNIEN, G. SOFF and V. KARA­SIEV / Parity Nonconserving ePNC) Electroweak Radiative Correc-

341-348

349-363

tions for Highly Charged Ions (HCI) 365-368

T. BEIER, A. N. ARTEMYEV, G. PLUNIEN, V. M. SHABAEV, G. SOFF and V. A. YEROKHIN / Vacuum-Polarization Screening Corrections to the Low-Lying Energy Levels of Heliumlike Ions 369-374

U. D. JENTSCHURA, P. J. MOHR and G. SOFF / Calculation of QED Effects in Hydrogen 375-377

V. G. PAL'CHIKOV / Testing of QED-Theory and Precise Measurements of the Rydberg Series for the He-Like Multicharged Ions 379-383

M. TOKMAN, P. GLANS, E. LINDROTH, Z. PESlC, R. SCHUCH and G. VIKOR / Accurate Calculations on Dielectronic Recombination Resonances in Cu-like Pb

V. A. YEROKHIN, V. M. SHABAEV, T. BEIER and 1. EICHLER / Cal­culation of the Interelectronic-Interaction Correction to Radiative Recombination of an Electron with a Heavy He-Like Ion

I. GOIDENKO, L. LABZOWSKY, A. NEFIODOV, G. PLUNIEN, G. SOFF and S. ZSCHOCKE / Evaluation of the Two-Photon Self-Energy

385-391

393-396

Correction for Hydrogenlike Ions 397-400

Nucle(/r the()n' and mass models

P. H. HEENEN / Mass Predictions from Mean-Field Calculations 401-407

T. OTSUKA / Monte Carlo Shell Model Mass Predictions

A. APRAHAMIAN, A. TEYMURAZYAN, A. SUSALLA and N. CUKA / From Exploding Stars to the Laboratory: Nucleosynthesis in the

409-416

rp-Process 417-424

S. LIRAN, A. MARINOV and N. ZELDES / Semiempirical Shell Model Masses with Magic Proton Number Z = 126 for Translead Elements 425-432

M. SAMYN, S. GORIELY and P.-H. HEENEN / Towards a Skyrme-Hartree-Fock-Bogolyubov Mass Formula 433-437

New mass measurement techniques, instrumentation and projects

H. WOLLNIK and A. CASARES / The Use of Multi-Pass Time-of-Flight Mass Analyzers for Nuclear-Decay Spectroscopy of Mass Identified Nuclei 439-442

N. I. TARANTIN / A Proposed Storage Ion Trap of an 'In-Flight Capture' Type for Precise Mass Measurement of Radioactive Nuclear Reaction Products and Fission Fragments 443-450

O. S. KOZLOV and S. I. KOZLOV / A Small Isochronous Storage Ring for Spectrometry 451-456

W. QUINT, J. DILLING, S. DJEKIC, H. HAFFNER, N. HERMANSPAHN, H.-J. KLUGE, G. MARX, R. MOORE, D. RODRIGUEZ, J. SCHON­FELDER, G. SIKLER, T. VALENZUELA, J. VERDU, C. WEBER and G. WERTH / HITRAP: A Facility for Experiments with Trapped Highly Charged Ions 457-461

G. MARX, D. ACKERMANN, J. DILLING, F. P. HESSBERGER, S. HOFF­MANN, H.-J. KLUGE, R. MANN, G. MONZENBERG, Z. QAM­HIEH, W. QUINT, D. RODRIGUEZ, M. SCHADEL, J. SCHON­FELDER, G. SIKLER, C. TOADER, C. WEBER, O. ENGELS, D. HABS, P. THIROLF, H. BACKE, A. DRETZKE, W. LAUTH, W. LUDOLPHS, M. SEWTZ and the SHIPTRAP Collaboration / Status of the SHIPTRAP Project: A Capture and Storage Facility for Heavy Radionuclides from SHIP 463-468

F. AMES, P. SCHMIDT, O. FORSTNER, G. BOLLEN, O. ENGELS, D. HABS, G. HUBER and the REX ISOLDE Collaboration / Space-Charge Effects with REXTRAP 469-472

D. BECK, F. AMES, M. BECK, G. BOLLEN, B. DELAURE, P. SCHUUR-MANS, S. SCHWARZ, P. SCHMIDT, N. SEVERIJNS and O. FORSTNER / Space Charge Effects in a Gas Filled Penning Trap 473-478

P. DELAHAYE, G. BAN, D. DURAND, A. M. VINODKUMAR, C. LE BRUN, E. LIENARD, F. MAUGER, O. NAVILIAT, J. SZERYPO and B. TAMAIN / Weak Interaction Studies Using a Paul Trap 479-484

R. BERAUD, G. CANCHEL, A. EMSALLEM, P. DENDOOVEN, I. HUIKA­RI, W. HUANG, Y. WANG, K. PERAJARVI, S. RINTA-ANTILA, A. JOKINEN, V. S. KOLHINEN, A. NIEMINEN, H. PENTTILA, J. SZERYPO, J. AYSTO, B. BRUYNEEL and A. POPOV / Status of HIGISOL, a New Version Equipped with SPIG and Electric Field Guidance 485-490

M. CZANTA, C. STRIETZEL, H. I. BESCH, H. F. BEYER, F. BOSCH, R. DESLATTES, F. FORSTER, A. GUMBERIDZE, G. HOLZER, P. INDELICATO, C. KOZHUHAROV, O. KLEPPER, A. KRAMER, D. LIES EN, T. LUDZIEJEWSKI, X. MA, B. MANIL, G. MEN­ZEL, N. PAVEL, A. SIMIONOVICI, M. STECK, T. STOHLKER, S. TOLEIKIS, I. TSCHISCHGALE, A. H. WALENTA and O. WEHRHAN / Spectroscopy of Ly-a Lines at Storage Rings by Crystal Spectrometry and Absorption Edge Technique 491-494

J. DILLING, D. ACKERMANN, F. P. HEBBERGER, S. HOFMANN, H.-I. KLUGE, G. MARX, G. MUNZENBERG, Z. PATYK, W. QUINT, D. RODRIGUEZ, C. SCHEIDENBERGER, J. SCHON­FELDER, G. SIKLER, A. SOBICZEWSKI, C. TOADER and C. WEBER / A Physics Case for SHIPTRAP: Measuring the Masses of Transuranium Elements 495-499

A. DRETZKE, H. BACKE, G. KUBE, W. LAUTH, W. LUDOLPHS, A. MOR­BACH and M. SEWTZ / Prospects of Ion Chemical Reactions with Heavy Elements in the Gas Phase 501-504

O. ENGELS, L. BECK, G. BOLLEN, D. HABS, G. MARX, J. NEUMAYR, U. SCHRAMM, S. SCHWARZ, P. THIROLF and V. VARENTSOV / First Measurements with the Gas Cell for SHIPTRAP

A. KELLERBAUER, G. BOLLEN, J. DILLING, S. HENRY, F. HERFURTH, H.-J. KLUGE, E. LAMOUR, D. LUNNEY, R. B. MOORE, C. SCHEIDENBERGER, S. SCHWARZ, G. SIKLER and J. SZE­RYPO / Improvement of the Applicability, Efficiency, and Precision

505-509

of the Penning Trap Mass Spectrometer ISOLTRAP 511-515

M. GOCHITASHVILI, B. KIKIANI and R. LOMSADZE / Electron Capture and Dissociative r~citation in Slow Collisions of Na+ and K+ Ions with Hydrogen and Nitrogen Molecules 517-520

M. MAIER, C. BOUDREAU, F. BUCHINGER, J. A. CLARK. J. E. CRAW­FORD, I. DILLING, H. FUKUTANI, S. GULICK, I. K. P. LEE, R. B. MOORE, G. SAVARD, J. SCHWARTZ and K. S. SHARMA / Stopping, Trapping and Cooling of Radioactive Fission Fragments in an Ion Catcher Device 521-525

A. NIEMINEN, I. HUIKARI, A. JOKINEN, J. AYSTO and the EXOTRAPS Collaboration / Time Characteristics of the Ton Beam Cooler-Buncher at JYFL 527-530

C. SCHEIDENBERGER, F. ATTALLAH, A. CASARES, U. CZOK, A. DO­DONOV, S. A. ELISEEV, H. GEISSEL, M. HAUSMANN, A. KHO­LOMEEV, V. KOZLOVSKI, YU. A. LITVINOV, M. MAIER, G. MUNZENBERG, N. NANKOV, yu. N. NOVIKOV, T. RADON, J. STADLMANN, H. WEICK, M. WEIDENMULLER, H. WOLL­NIK and Z. ZHOU / A New Concept for Time-of-Flight Mass Spectrometry with Slowed-down Short-Lived Isotopes 531-534

L. WEISSMAN, F. AMES, J. AYSTO, O. FORSTNER, S. RINTA-ANTILA, P. SCHMIDT and the ISOLDE Collaboration / Feasibility of In-Trap Conversion Electron Spectroscopy 535-539

Key Word Index 541-543

..... , Hvperjine interactiolls 132: 1-6, 200 I. t ..

Foreword - Organizing APAC2000

D. LUNNEY

About three years ago, Juergen Kluge had the idea of proposing a series of con­ferences dedicated to what we loosely call "atomic" physics, but performed at accelerator facilities. Hence the acronym: APAC. Though much of this physics targets the nucleus, the surrounding atomic system is used to access this recalci­trant, quantum, many-bodied system that has defied an exact theoretical description since its discovery, long ago.

Thanks to the inherent precision of lasers, we are able to probe the very sub­tle effects of the nucleus on atomic energy levels as manifested by the hyperfine spectrum. Optical spectroscopy, yielding information on nuclear moments and the charge radius, was the central theme for the first in the series of APAC Euro­conferences*. Held in Budenheim (Germany), the proceedings of APAC99 were published in Hyper.tine Interactions (Volume 127, 2000). This second meeting in the series, held in Cargese (France), was devoted to the field of mass spectrometry but more specifically: atomic mass measurements. With a profound influence not only on nuclear but also on atomic physics, such measurements form the heart of several research programs worldwide, as these proceedings attest. Completing the Euroconference triumvirate will be APAC2001, to be held in Aarhus (Denmark), dedicated to studying the interplay between the nucleus and the various atomic charge states.

The field of mass measurements is as old as nuclear physics itself, even pre­dating the discovery of the neutron. Since that time, measurement precision has constantly improved (roughly at a rate of one order of magnitude per decade), revealing new detail of the mass landscape that guides us in our quest to understand the nuclear interaction. The application of mass measurements using direct tech­niques of mass spectrometry at accelerators was pioneered by the atomic masses group at the Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse (CSNSM) in Orsay. For this reason, Juergen Kluge asked our group to organize APAC2000.

Unlike most other properties in physics, the mass is subject to a special treat­ment known as the Atomic Mass Evaluation. This is necessary due to the very definition of the mass unit (one twelfth the mass of 12C) and due to the myr­iad interconnections of masses via reactions and decays. The Grand Inquisitor of atomic masses, Aaldert Wapstra, has tirelessly devoted himself to this rigorous

* Partly financed by thc EC under contract number ERBFMMACT980469.

2 D.LUNNEY

The village of Cargese with its Greek (left-handed) and Latin (right-handed) churches. Note the symmetry breaking.

Aaldert Wapstra, at the conclusion of the tutorial honoring his seminal contribution to the Atomic Mass Evaluation, recalling some of his memories.

task for decades. On the recommendation of his evaluator-partner Georges Audi, we decided that APAC2000 would be an apt opportunity to acknowledge Aaldert Wapstra's giant contribution, still continuing in this, his 79th year. The occasion was a tutorial session, during which the various fields of physics where masses have their greatest impact were reviewed. We are happy to include his views on the subject (which he has titled "memories") in these proceedings.

The program was an ambitious undertaking with one day devoted to the tutorial and another two days for status reports of the several groups actively pursuing mass measurement programs via a panorama of techniques: reactions, decays, spec­trometers, cyclotrons and notably, Penning traps. Since masses require precision measurements, and since on-line conditions at accelerators present very particular and challenging measurement conditions, a part of the program was dedicated to these related technical developments.

FOREWORD - ORGANIZING APAC2000 3

Annette Paul (PTB, Braunschweig) describing the old kilogram (inset) and its proposed re­placement - a high purity Si ball comprised of a known number of atoms. Annette's talk on the AVOGADRO project was voted the best of the meeting.

Perhaps the most unique aspect of APAC2000 was the interface between nu­clear and atomic physics via their respective binding energies. The accuracy of measurements using trapped, highly charged ions is now such that state-of-the-art QED calculations must be pushed to higher order.

Nuclear theory made up the balance of the program, notably for its necessary and important role in stellar nucleosynthesis modeling.

In constructing the APAC2000 program, I relied chiefly on my perception of how the field of mass measurements ought to be captured for posterity at this moment of what seems to me, a zenith. Of course, I also relied on the council of Juergen Kluge for the atomic physics component and general aspects of Eu­roconference organization. I was in frequent consultation with my colleagues in Orsay: Georges Audi, Michel de Saint Simon, Catherine Thibault, Hubert Doubre and Dominique Guillemaud-Mueller. The International Advisory Committee was solicited for prioritizing the speaker lists and I am grateful to those who responded, especially to Ernst Roeckl, an ex-officio member who made numerous suggestions to help shape the tone of the meeting. I would like the acknowledge the role played by Catherine Thibault in the management of financial matters - an activity that lay dormant up until the meeting at which point it exploded into frenzied activity during the week, causing her a significant loss of sleep. (Not enough however to

4 D.LUNNEY

The "official" conference photo, taken by the organizer during his own talk. Note the surprised look of the audience.

The conference shuttle bus, packed beyond the space-charge limit of passenger density.

deprive us of an apt and charming conference summary.) My thanks go also to Monique Perrin for her secretarial aid before, during and after the meeting, to my colleague Carole Gaulard and to our students Celine Monsanglant, Nelson Vieira and especially, Sylvain Henry for his innumerable shuttle voyages between the conference center and the village of Cargese.

I would like to thank the staff of the Institut d'Etudes Scientifiques in Cargese without whom the logistical part of the meeting would have been beyond my worst nightmare. Brigitte, Nathalie, Pierre-Eric and especially, Chantal Ariano worked with tireless dedication, taking care of the local booking and transportation and even cooking our delicious conference dinner. Thanks to Chantal, we managed to negotiate and subsequently re-schedule the boat cruise to the Scandala nature reserve. The wind-driven Mediterranean high seas were impressive to behold -

FOREWORD - ORGANIZING APAC2000 5

The conference site - and perfect occasion for an ISOLTRAP collaboration meeting.

Girolata - midpoint of our excursion and accessible only by sea. (One of us enjoyed it so much he missed the boat!)

better from the shore than on a boat. Rare in Corsica is rainfall of which we had the dubious pleasure during our stay on the parched (sometimes even burning!) isle. I think we all enjoyed the spectacular Calanques de Pinata and the pays des Quatres Tours.

In summary, my own expectations (not to mention fears) were fulfilled and even, surpassed. But while personal satisfaction is one thing, the greatest pleasure comes from the reactions of the participants, a large number of whom have shared with

6 D.LUNNEY

Rescuing the mechoui from disaster?

me their appreciation of the meeting. Perhaps one regret: while the conference barbecue was excellent, we did not resolve the mysterious prophecy, recalled by Ernst Roeckl, of " ... Charles, nearly rescuing the mechoui from a disaster . .. " But happily, there are still mysteries in our field.