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scopes. He mentioned the problem ofbiasing, and showed that future large-scale surveys such as that beingplanned on the CFHT will provide easydiscrimination. H. Böhringer providedthe evidence from clusters of galaxies,showing that three independent ap-proaches all give a good fit with theconcordance model.

steps in this analysis, and stressed theimportance of the local calibrators. Inthe future thousands of distant super-novae will be accessible with the largetelescopes. Y. Mellier spoke on the ob-servations of cosmic shear from weakgravitational lensing, stressing the ex-cellent agreement between six differentteams working with six different tele-

Astronomy, cosmology and funda-mental physics have thriving interfacesand modern research topics that bringtogether scientists from these differentdomains. New results and open ques-tions call for meetings covering all ofthese fields. This year saw the firstsuch meeting jointly organized by thethree organizations ESO, CERN andESA. The symposium took place inGarching on 4-7 March with about 200participants. It gave a broad overviewand so consisted largely of invited talks,with some contributed talks and over 50posters on display.

The Director General of ESO, Dr.Catherine Cesarsky, opened the Sym-posium with an overview of the cur-rent state of many of the fields to bediscussed at the Symposium. Shestressed the rapid pace of developmentin all of these areas, ranging from thespectacular convergence of the majorcosmological parameters to the discov-ery of over 80 extrasolar planets.

N. Turok introduced the cosmologypart of the Symposium with a stimulat-ing talk provocatively entitled “TheEarly Universe – Past and Future”. Hechallenged the relation of the remark-able cosmic concordance picture withstandard inflationary models of theUniverse, and described a possible al-ternative involving an infinite recyclingof the Universe through collidingbranes, in which time is eternal.Possible tests could be provided by acorrelation of an all-sky CBR map withX-ray surveys or by CBR polarizationmeasurements.

A series of talks dealt with the evi-dence for and remarkable convergenceof the cosmological parameters. P. deBernardis described the amazing newresults from the current microwavebackground observations. With the im-proved data three accoustic peaks inthe structure of the microwave back-ground are seen. Results will soon becoming from the MAP satellite, whichhas already surveyed 85% of the sky.Polarization measurements will be crit-ical in testing the adiabatic inflationaryscenario. B. Leibundgut gave the evi-dence from high-redshift supernovastudies for an accelerating Universe.He gave a critical assessment of the

Summary of the ESO-CERN-ESA Symposium onAstronomy, Cosmology and Fundamental Physics Held at Garching bei München, Germany, 4-7 March 2002

M. JACOB1, P. SHAVER 2, L. DILELLA3, A. GIMENEZ 4

1Chairman, Joint Astrophysics Division of the EPS and EAS2ESO 3CERN (European Centre for Nuclear Research, Geneva, Switzerland)4ESA (European Space Agency, ESTEC, Noordwijk, Netherlands)

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experiments have provided for the firsttime a clear demonstration of the exis-tence of the three-boson interactionpredicted by the electroweak theory. Inthe framework of the Standard Model,the LEP measurements have beenused to constrain the mass of the Higgsboson, which is the only missing pieceof the theory. The prediction is mH =85 +54

–34 GeV, giving good hopes for thediscovery of this particle at one of thefuture high-energy colliders (the im-proved proton-antiproton collider atFermilab, which is presently in the com-missioning phase, or, more likely, theCERN LHC). Gianotti also reviewed thehint for the production of the Higgs bo-son with a mass of 114 GeV, obtainedby the LEP experiments during the lastyear of LEP operation. Gianotti con-cluded that the prospects to discoverthe Higgs boson at the LHC are excel-lent, as are the prospects to discoverthe supersymmetric partners of knownparticles, if they exist.

Pierre Le Coultre showed how one ofthe LEP detector (L3) can be used as adetector for cosmic ray muons. The re-sults will constrain cosmic ray modelswhich are used to predict the fluxes ofatmospheric neutrinos.

Despite its successes, the StandardModel of particle physics contains toomany parameters and theorists donot see it as the final theory. In ad-dition, it does not include gravitationalinteraction, and the mass of the stan-dard Higgs boson becomes unstablewhen quantum corrections are takeninto account. J. Ellis discussed newphysics which could solve these prob-lems. The most popular model isSupersymmetry, which adds a newscalar boson to each known fermion,and a new fermion to each knownboson. These hypothetical particleshave not yet been discovered, but the-orists are confident that their massesare lower than 1 TeV, if they exist. The

only very weakly with matter, such asneutralinos. A claimed signal from theDAMA experiment at Gran Sasso hasnot been confirmed by other experi-ments. Several experiments are pres-ently taking data and more sensitive ex-periments are in preparation.

P. Hernandez summarized the evi-dence for neutrino oscillations. Recentresults using solar and atmosphericneutrinos provide convincing evidencefor neutrino oscillations, requiring thatneutrinos have a non-zero mass.Neutrino oscillations are probably themost important new phenomenon dis-covered in particle physics in the lastdecade (although their masses are notsufficient to provide an appreciablecontribution to dark matter). Intense ex-perimental activity is presently inprogress. In the longer term, neutrinobeams with much higher fluxes will berequired to study this phenomenon indetail, including the possible observa-tion of CP violation.

The Standard Model of ParticlePhysics and the tests performed at lowenergies were described by A. Pich,highlighting the very impressive preci-sion achieved in comparing measure-ments with theoretical predictions inparticular cases. He also reviewed re-cent results on CP violation. During thelast year large CP violating effects havebeen reported, and future experimentsshould clarify the mechanisms respon-sible for this phenomenon.

High energy tests of the StandardModel were reviewed by F. Gianotti.These include the studies of the W andZ bosons at the e+e- collider LEP andthe discovery of the top quark at theFermilab proton-antiproton collider. TheW and Z masses are presently knownwith a precision of 0.05% and 0.0024%,respectively, and other parameters ofthe Standard Model measured at LEPare measured with typical precisions ofthe order of 0.1%. In addition, the LEP

A comprehensive overview of thecurrent state of our knowledge of thecosmological parameters was providedby L. Krauss. He started with theHubble constant, showing the excellentagreement between different groups.He summarized results from the CMBfluctuations, the ages of the oldeststars, the baryon density from deuteri-um and 3He measurements, the darkmatter density from X-ray clusters, thelarge scale structure results from theSloan and 2DF surveys, and concludedthat everything fits (the “concordancemodel”), but that the theoretical basisremains unclear.

A. Vilenkin addressed the Cosmo-logical Constant Problems (CCPs) andtheir Solutions. The two major prob-lems cited were the value of the vacu-um energy density, and the “time coin-cidence problem” (i.e. why we happento live just at the time when the vacuumenergy dominates). He considered pos-sible particle physics solutions, BraneWorld solutions, Quintessence models,and the Cosmological Anthropic Prin-ciple. He concluded that the anthropicapproach naturally resolves both CCPsand opens windows to the super-largescales beyond the visible Universe.

One of the major transition phases ofthe observable Universe, the “Reioni-zation Epoch” when the first starsformed and ended the “Dark Ages” thatfollowed recombination, was discussedby P. Madau. He described theories forthe development of the early massivestructures, and reviewed evidence thatthe helium reionization epoch may al-ready have been detected.

Direct searches for dark matter can-didates were reviewed by C. Tao.Gravitational microlensing searches formassive baryonic objects explain atmost 20% of the dark matter in ourGalaxy. Other searches focus on thepossible existence of hypothetical mas-sive, neutral particles which interact

A press conference was held during the Symposium. From left to right are Prof. Sir Martin Rees (Cambridge University), Dr. David SouthwoodESA), Dr. Catherine Cesarsky (ESO Director General), Dr. John Ellis (CERN), and Dr. Michel Mayor (Observatoire de Genève).

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hunt for supersymmetric particles willbe one of the main activities at the LHC.Ellis discussed additional theoreticalideas which could give rise to unex-pected and spectacular events at theLHC.

Stimulated by a recent claim on thebasis of high redshift QSO spectra thatthe fine structure constant Alpha maybe varying with cosmic time, G. Fioren-tini reviewed other possible evidencefor its variation. So far the only positiveclaim is that from the QSO spectra,conflicting with the other evidence, andmore dedicated experiments will berequired to solve this puzzle.

The first of a series of talks on highenergy astrophysics was given by E. vanden Heuvel. He spoke about GammaRay Bursts, the most powerful knowncosmic explosions. The models involverelativistic fireballs from either super/hypernovae (“collapsars”), or the merg-ers of neutron stars with other neutronstars or black holes. A few thousandsuch bursts have now been observed;the most distant so far known is at z =4.5. The Swift satellite, to be launchednext year, will provide rapid responseand accurate positions for follow-up bytelescopes such as the VLT.

H. Völk reviewed the subject of high-energy γ-rays. In the region up to a fewGeV, these γ-rays are detected bymeasuring their conversion to e+e- pairsin satellites, while at higher energies(up to 100 TeV) ground-based Čeren-kov detectors are used to detect theelectromagnetic showers produced inthe Earth’s atmosphere. Progress inthis field is expected from the futureGamma Ray Large Area Telescope(GLAST) satellite mission which willstudy γ-rays up to energies of 100 GeVby means of a detector combining largeacceptance and excellent angular andenergy resolution.

Studies of cosmic rays at extremelyhigh energies (up to 1020 eV) were re-viewed by A. Watson. The interaction ofthese particles with the Earth’s atmos-phere produces extended air showerswhich are studied by counting the muonmultiplicity in a large number of detec-tors scattered over a large area. Thelarge Pierre Auger Laboratory inArgentina will start data taking soon.Another experiment, EUSO, will meas-ure the nitrogen fluorescence from veryhigh-energy cosmic rays using detec-tors mounted on the InternationalSpace Station, with the advantage ofcovering a much larger area thanground-based experiments.

The presence of some reportedevents of extreme energy (above 1011

GeV), such that proton primariesshould have been stopped by thecosmic microwave radiation, raises animportant puzzle. With respect to pri-mary charged particles, high energyneutrinos and γ-rays have the advan-tage of pointing to the source. Neu-

trinos interact weakly, so they arethe only particles that can provideinformation from the edge of theUniverse and from sources deep insideactive regions. However, detectors withvery large masses are needed. F. Hal-zen reviewed the status of AMANDA,a large detector consisting of stringsof photomultiplier tubes buried deep inthe Antarctic ice cap and looking downto measure Čerenkov radiation in icefrom charged particles. Other underwa-ter experiments built on the same prin-ciple are operating and in preparation.

The X-ray background has now beenalmost completely resolved into dis-crete sources by the latest satellites,Chandra and XMM. As described by G.Hasinger, many of these sources in-volve optically obscured active galacticnuclei (AGN), with accretion onto cen-tral black holes. The redshift distribu-tion peaks at a surprisingly low redshift,z ~ 0.6, and there is a clear deficit at z> 4, indicating a decrease in the spacedensity at high redshift, in agreementwith earlier results on QSOs. Futuremissions such as Rosita, Duet andXeus may find some of the very rarehigh-redshift X-ray QSOs.

L. Woltjer gave an assessment of ourcurrent knowledge of neutron stars.The masses and temperature fit the“standard solution”, and there havebeen many models that agree. Pulsarshave provided new constraints andproblems, one of which was the rela-tively few radio pulsars located in su-pernova remnants. Now it is known thatthere are objects in about 80% of su-pernova remnants. There has been acontinuing debate over the velocities ofneutron stars, and its resolution will beimportant in the understanding of theirorigins.

The ubiquity of black holes in thecentres of galaxies is now widely be-lieved. R. Bender outlined the evidencefor several cases. Spectacular new ev-idence has come from X-ray spectra,

which indicate strong gravitational ef-fects. Only supermassive black holesprovide a plausible explanation for allsuch phenomena, although direct evi-dence is still hard to obtain. Super-massive black holes appear to be pres-ent in most galaxies, and there are cer-tainly enough to explain the QSO phe-nomenon. A. Eckart showed striking ev-idence for the black hole in the centreof our own Galaxy. The proper motionsof stars in the inner region imply an en-closed mass which is almost certainly ablack hole.

Gravitational waves were the subjectof the next two talks. B. Schutz re-viewed the possible sources of gravita-tional waves. The merging of two blackholes of a million solar masses at z = 1would give an amplitude 5 orders ofmagnitude higher than the detectionthreshold of LISA. The merger wouldtake only minutes but the spiral down,with a varying frequency of 0.1 to 10mHz, would take months. For stable bi-naries, observing the signal over manyperiods greatly helps in reaching loweramplitudes. There is complementaritybetween detectors on the ground (fre-quencies above 10 Hz) and detectors inspace (set at frequencies below 0.1Hz), The amplitude sensitivity should inboth cases reach below 10–22 K. Danz-mann then outlined the prospects fordetecting gravitational waves. Heshowed that resonating ground detec-tors were limited to the detection of asupernova in the galaxy but that morepromising prospects were offered by in-terferometers. LIGO should reach to 20Mpc soon for such a signal, and to 200Mpc in 2006. For LISA, prospects aregreat for the observation of massiveblack holes merging anywhere in theuniverse.

S. Vitale described other space mis-sions on fundamental physics understudy at ESA. STEP should test theequivalence principle at the level of10–18, 6 orders of magnitude better than

Participants enjoying the Symposium buffet dinner.

the present limit. The ACES mission, onthe ISS, should produce a very highprecision clock and the HYPER one(free flyer) should study cold atom in-terferometry in space with the prospectof making very high sensitivity gyro-scopes. R. Battiston discussed as-troparticle physics from space, pointingout that cosmic ray studies were thebeginning of particle physics. He re-viewed the studies of cosmic raysmade with balloons and satellites, andthe prospects for searches for new par-ticles: antimatter, dark matter, and ul-traheavy particles. A new detector witha sensitivity to anti-nuclei improved bya factor of 1000 will be installed on theInternational Space Station.

G. Raffelt discussed how stars canbe intense sources of weakly interact-ing particles. One such particle is theaxion, which was conceived to explainthe absence of CP violation in thestrong interaction. A CERN experiment(CAST) will search for axions using anLHC magnet pointed at the Sun and de-tecting the axion – X-ray conversion inthe magnetic field.

F. Paresce described the first scienceresults from the VLT interferometer. Alarge number of stellar sources withcorrelated magnitudes brighter thanK ~ 6 and K ~ 3 have been observedwith the 8m and 40cm telescopes res-pectively, allowing the establishment oftighter constraints on theoretical stellarmodels. The great scientific potential ofthe full VLTI system was outlined.

A group of three talks dealt with theexciting new field of extrasolar planets.E. van Dishoeck described observa-tions and theories of forming planetarysystems. Infrared and millimetre emis-sion comes from dusty disks surround-ing many young stars. The chemistry ofthese circumstellar disks, deducedfrom observations of the many molecu-lar lines, provides essential clues totheir evolution and planet formation.For future observations high angularresolution will be essential, and ALMAwill play a dominant role. Other impor-tant facilities will include the VLT/VLTI,SIRTF, NGST and Herschel.

The spectacular advances in the dis-covery of extrasolar planets (from nonein 1995 to over 80 today) were de-scribed by M. Mayor. There is a hugediversity, which was unexpected. Manyare at 0.03–0.05 AU, many have ec-centric orbits, and typical masses are inthe range 0.15–10 MJ/sin i. Most havebeen discovered from radial velocitymeasurements. Photometric transitshave also now been observed – 46 ofthem from one recent survey alone.And there are now 7 or 8 published sys-tems with multiple planets. Many as-pects are now being actively studied –the origins of the “hot Jupiters”, themass functions of substellar compan-ions, the orbital eccentricities, the rela-tion to the metallicity of the star. For the

future, M. Mayor mentioned the newHARPS instrument for the ESO 3.6mtelescope, the possibility of astrometrywith Prima on the VLT, and prospects inspace.

M. Perryman followed on from M.Mayor’s talk by considering theprospects for the detection of earth-likeextrasolar planets – lower mass sys-tems, in particular ones where life mightform. He described prospects with theastrometric mission GAIA, due forlaunch in 2010-2012. With its 1 micro-arcsec accuracy, it will detect 20,000–30,000 planetary systems, and will find~ 10,000 planetary systems by photom-etry alone. The later Eddington missionwill detect photometric transits of500,000 stars, including some 2,000due to earth-mass planets. The photo-metric accuracy will suffice to detectplanetary rings and moons. Finally, heconsidered the conditions thought nec-essary for life. The DARWIN mission,with a launch date sometime after2015, would be a 50-250m baseline in-terferometer employing six 1.5m tele-scopes. It would make possible directimaging of solar systems like ours, andseek spectral signatures of possiblebiomarkers. Surface imaging of earth-like extrasolar planets may be possiblewith the next generation of extremelylarge telecopes (OWL, CELT), and verylarge space arrays.

During the last afternoon there weretalks on the future perspectives at ESA,CERN and ESO. Many exciting proj-ects are under construction or at theplanning stage in all three organisa-tions. D. Southwood gave a long andimpressive list of ESA space missions,present and future, with five launches injust the next year and plans extendingwell over a decade into the future. Heconcluded with comments on the role ofscience in Europe, highlighting the dec-laration of the EU Council of Ministersthat “Europe should become the mostcompetitive and dynamic knowledgebased economy in the world”.

The future of CERN was reviewed byJ. Ellis. In the short term most of theCERN effort is devoted to the construc-tion of the Large Hadron Collider(LHC), a machine where two protonbeams, each with an energy of 7 TeV,collide head-on with an interaction rateof 5 108 s–1 in each of two general-pur-pose detectors. The LHC and detectorsare now in the construction phase andphysics should start in 2007. The LHCwill also accelerate heavy ions to studythe so-called “quark-gluon plasma”,which is the state of matter of the earlyUniverse before baryogenesis. Ellisalso reviewed the R&D activity on ac-celerator technology which goes on inparallel with LHC construction, to pre-pare for the post-LHC era.

ESO’s current and future pro-grammes were outlined by the DirectorGeneral, C. Cesarsky. All four 8-meter

unit telescopes of the VLT are operatingwith high efficiency, and the suite ofVLT instruments is rapidly increasing.Two survey telescopes are also beingadded. Adaptive optics systems havegiven the VLT images added sharp-ness, and the VLT Interferometer hasalready started producing science, asoutlined earlier by F. Paresce. A majornew ESO project is the Atacama LargeMillimeter Array (ALMA), which, with its64 12-meter antennas operating at5000m altitude, will become a millime-ter/submillimeter equivalent of theVLT/VLTI and NGST. It will be an equalpartnership with the U.S. and possiblyJapan, with completion foreseen for2011. Further into the future will beOWL, a giant 100-meter diameter opti-cal-infrared telescope, and scientificand technical investigations for this fa-cility are already well underway.

The concluding lecture was given byM. Rees. He saw the Symposium aslinking the very small with the verylarge, and mentioned three major de-velopments discussed at the meeting:the discovery of extrasolar planets, theevidence on neutrino masses, and thedetermination of important key num-bers of the Universe in just the last fewyears. He remarked on how conclu-sions regarding the flat Universe and itscontents (5% baryons, 25% dark mat-ter, and 70% dark energy) have comefrom independent sources, with amaz-ing agreement, and the challenges theypose to particle physics. In ten yearshence he expects the basic parametersto be well known, and he reflected onthe two major challenges that may faceus in the post-2010 era: an under-standing from the very early (<10-12

sec) Universe as to why these numbershave these particular values, and anunderstanding of cosmic evolution at>108 yrs. In the latter context he con-sidered the possible detection of theearliest luminous objects, the formationand evolution of galactic nuclei andblack holes, the mysteries and potentialof Gamma Ray Bursts, and the proba-ble detection of gravitational wavesfrom such objects. Finally, he speculat-ed on the mysteries of the very earlyUniverse. In particular, why do the lawsof our Universe have latent in them allthe complexity of our Universe? Thereare now many models, and he won-dered how many Big Bangs? Accordingto the Cosmological Anthropic Prin-ciple, the laws of our Universe just hap-pen to be “the by-laws governing ourpatch”. With the rapidly increasing datarates he anticipated the development ofhuge databases making possible awider participation in science, and hefelt that the crescendo of the last fewyears will continue with the great newscientific facilities becoming available.

Finally, over 50 poster papers werepresented, covering a wide range of ex-citing topics including cosmological

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models, Quintessence, the CMB, cos-mic shear, the cosmological constants,Gamma Ray Bursts, galaxy formation,galaxy clusters, gravitational lensing,new space missions, probes for super-massive black holes, quasar absorptionline studies, experiments in fundamen-tal physics, extrasolar planets and oth-ers. The programme included a fasci-nating special evening lecture by Jean-Claude Carrière, well-known author, onthe subject of “Time”.

The full proceedings of this Sympo-sium will be published in the Springer-Verlag series “ESO Astrophysics Sym-posia”.

The Scientific Organizing Committeewas comprised of: R. Battiston (Univ. ofPerugia), R. Bender (Univ. of Munich),A. de Rujula (CERN), L. DiLella (CERN),C. Fabjan (CERN), A. Gimenez (ESA),M. Jacob (JAD), F. Pacini (Arcetri), A.Renzini (ESO), P. Shaver (ESO; chair),M. Spiro (Saclay), B. Taylor (ESA), P. van

der Kruit (Univ. of Groningen), S. Vitale(Univ. of Trento), S. Volonte (ESA), andM. Ward (Univ. of Leicester).

We are most grateful to the Sym-posium Secretaries Britt Sjöberg ofthe ESO/ESA ST-ECF and ChristinaStoffer of ESO for the organizationalwork before and during the Sympo-sium, and to the ESO students and fel-lows, led by Harald Kuntschner, wholooked after the facilities during themeeting.

The Tarantula Nebula in the Large Magellanic Cloud – ESO/MPG 2.2-m telescope (ESO PR Photo 14a/02.)