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Explore the best approach to advocate for a Super B Factory & the significance of exploring new physics. Addressing the challenges and opportunities in elementary particle physics.
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Can we make an effective case for a Super B Factory ? David HitlinSuper BFactory Workshop, Honolulu April 22, 2004 David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Making an effective case for a Super B Factory • Most of us at this Workshop are familiar with the measurement capabilities of a Super B Factory, comparisons with hadronic experiments, ………. (see MacFarlane, Yamauchi, …….. presentations) • I will not, therefore go into these areas in detail • The question I want to address is “What is the most effective way to make the case for a Super B Factory ?” and to motivate the investment of 0.5 Joint Strike Fighter planes in this goal • Having demonstrated the consistency of tree-level Unitarity Triangle physics with the Standard Model, we now have a uniquely sharp tool to explore the details of New Physics that we trust will be unearthed at the LHC • This is not, to the attendees of this Workshop, a particularly controversial point of view, but we have not yet succeeded in making the case clearly to the wider HEP community David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
EPP2010 • The US National Academy of Sciences (Board on Physics and Astronomy) study on Elementary Particle Physics in the 21st Century(http://www7.nationalacademies.org/bpa/EPP2010.html) is underway, with a report expected in late 2005 or early 2006 • Charge • “Identify, articulate, and prioritize the scientific questions and opportunities that define elementary-particle physics • Recommend a 15-year implementation plan with realistic, ordered priorities to realize these opportunities” • The future of flavor physics in the US, as well as the participation of the US HEP community in flavor physics elsewhere, is crucially dependent on the outcome of this study • We are attempting to communicate effectively with the committee, which consists of HEP and non-HEP physicists, as well as non-physicists • How the recommendations of this report will be factored into DOE planning remains an open question David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
The real world • When the EPP2010 Committee visited SLAC in January, Bob Cahn, at the invitation of the committee, gave a presentation on B physics • He characterized the physics of Super B Factories as “shake the box” physics, and the physics of LHC as “open the box” physics David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
The real world • When the EPP2010 Committee visited SLAC in January, Bob Cahn, at the invitation of the committee, gave a presentation on B physics • He characterized the physics of Super B Factories as “shake the box” physics, and the physics of LHC as “open the box” physics • This prompted committee member Harold Varmus, Nobel Laureate in Physiology or Medicine, 1989, to proclaim himself an “open the box kind of guy” • Ironically, there seems to be great enthusiasm in the community and the EPP2010 Committee for the next generation of neutrino experiments, which is, of course, “shake the box” physics • From this, and many other remarks, I conclude that although there is a very strong physics case for a Super B Factory, we have to this point not been particularly successful in convincing to the community • What happened to the argument that virtual effects were a powerful tool, since they allow you to access very high scales? • The question we must all urgently address, therefore, is how to educate the community that the physics that can be uniquely uncovered by measurements sensitive to virtual effects is important and worth a significant new investment David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Vulnerabilities • At EPP2010 at SLAC, David Gross, Nobel Laureate in Physics, 2004, a panel member, remarked. rhetorically, “What have we ever learned from flavor physics?” • Gross is also the author of The 25 Most Important Questions of Physics Question 7 - “The problems not solved by the Standard Model of particles: Particle types, masses and mixing, unification of forces ....” Question 8 – “The existence of supersymmetry: Does this framework for new physics appear at accessible energies?....” • My answer: parity and CP violation, unitary symmetry, the existence of generations,the Standard Model, and, perhaps, the existence of physics beyond the SM For some reason, flavor physics (quark style) is passé, while flavor physics (neutrino style), is hot We have not effectively conveyed the importance and excitement of our achievements over the past several years, or the remaining potential of quark flavor physics at a Super B Factory David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Vulnerabilities, continued • Anomalous effects seen in by Belle/BABAR are intriguing, but … • Effects are still in the 3+s range • Belle /BABAR results on specific modes are not in detailed agreement • There are non-negligible SM theory uncertainties in many modes • Vulnerability will remain even if results in the next few years reach 4+s It is preferable to stress what can be achieved with the cleanest modes, and what is needed to measure them f23 mass insertion f13 mass insertion DACP (J/ KS-fKS) DACP (J/ KS-p0KS) fKS (now) fKS 30 ab-1 Ciuchini, Franco, Martinelli, Masiero, & Silvestrini David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Vulnerabilities, continued • Accelerator design performance is a very delicate issue • The peak and integrated luminosity performance must be conservatively specified • Parameters must withstand expert scrutiny • Operating costs are important • There is a trade-off between capital investment, operating costs and luminosity • Performance must be sufficiently aggressive to promise important results within a few years of turn-on • Evaluated on a comparable basis, KEK and SLAC concepts differ by factors of 2 to 3 This important difference is a subjective matter, but a vital one David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Vulnerabilities, continued • Too little, too late • Many important results require ~50 ab-1 • Most projects are expected to meet important new objectives within a few years of turn-on • LHCb results that overlap with Super B will begin to appear in 2009/2010 • Perhaps more important, discovery of SUSY is expected on this time scale It is crucial to have Super B results in time to promise a dialog with LHCA 50 ab-1 sample should be in hand as close to the middle of the next decade as is feasible David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Strengths • We have a strong track record • SLAC and KEK each built the current B Factories in a timely way, with reliable costing, have operated the facilities in a highly efficient manner and continue to improve performance • We have done the physics we promised to do, exceeding all expectations • We have made significant measurements and discoveries • We have attracted (mostly favorable) newspaper and magazine coverage • We have a strong and appropriate concern for • Making conservative estimates ofthe precision of our measurements, including systematics, and • The reliability of theoretical calculations • We have done much (but not all) of the accelerator and detector R&D required to make proposals for a major upgrade that can build on our accomplishments and play an interesting part in the post-LHC New Physics conversation David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Scenarios for the next decade • Evidence for SUSY (I will use SUSY to mean any kind of New Physics) will be found by ATLAS and CMS in the first few years of LHC operation • LHCb will take data on the same time scale • There will be an ILC, with first data in ~2020 • Does a Super B Factory have a place in this context? • It should have a place, but we have yet to find a sufficiently persuasive set of arguments to ensure this • Super PEP-II is not currently part of SLAC’s long range plan Tight budget constraints • Held hostage to ILC • Super KEK-B is not currently part of KEK’s long range plan Tight budget constraints • Held hostage to ILC David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
What can a Super B Factory bring to the party? • Flavor physics, whether b, c or t decays, provides • Sensitivity to New Physics (SUSY, extra dimensions, ……) • New CP phases, non-Standard Wilson coefficients, …… • Strong anduniqueconstraints on models of SUSY breaking • B(bsg) has already ruled out a host of New Physics models • Super B specific measurements • CPV in bs • FCNC (Kll, Knn …...) • LFV (tdecays) • Higgs mediation (B Dtn,etc.) • Precision CKM Unitarity Triangle parameters • This is not news. How do we effectively demonstrate the impact of these measurements? David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Much interesting work has already been doneon this topic. Can we find a more effective way to getthe message across? Scenarios for HEP in the next decade We are here LHCturns on LHC finds SUSY LHC doesn’tfind SUSY HEP What can a Super B Factory say about SUSY-breaking models? What canthe ILC say about SUSY-breaking models? David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
What will we learn about SUSY from the LHC? • The first evidence for SUSY may be from inclusive distributions Example: mSUGRA with squark masses ~700 GeV David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Exclusive studies are a game of edges and thresholds • If R parity is conserved, all SUSY particles decay to an invisible LSP , so there are no mass peaks. • It is possible to identify particular decays and to measure their kinematic endpoints, allowing the determination of combinations of masses • The three-body decay gives a dilepton endpoint at , while gives a triangular distribution with an endpoint at David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Correlations allow model discrimination David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Third generation squark signatures The main production mechanism is production and decay Example: mSUGRA with m0 = 100 GeV, m1/2 = 300 GeV, A0 = −300 GeV, tan β =10, sgn μ = + The decay chain is TheM( ) endpoint can be used to measure a combination of the squark masses. The analysis requires as usual multiple hard jets and large ETplus two jets tagged asb’s, two other jets not tagged asb’s and consistent with David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Opposite sign, same flavor distributions also yield Dm’s David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
There are also methods to get handles on combinations of the slepton mass, chargino masses, and perhaps, heavy gaugino masses and the spin David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Ultimate precision on masses requires ILC • LHC, by the mass difference and threshold methods, will measure SUSY masses to a precision of 5 to 10 GeV • ILC, a decade or so later, will dramatically improve the errors slepton masses can be measured with a threshold scanto a precision ~100 MeV with 10 fb-1 per point David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Combining LHC and ILC measurements (in >2020) • Can extract all SUSY parameters: example SPS1a Fittino David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Squark mass matrix (d sector) Super B Factory LHC A SuperBFactory, early in the LHC era, can provide the meansto eliminate potential models as well as unique information on CPphases David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Can we integrate Super B information into the SUSY program? • There have been many interesting exercises (see, for example, the talks of Okada and Iijima on Wednesday) showing how, with improved precision, heavy quark and t measurements can uniquely discriminate between SUSY breaking models • These studies relevant and persuasive • We must find a mechanism to more effectively insert these approaches into the mainstream LHC/ILC conversation • Is there a way, for example, to extend a global fitting program such as Fittino to incorporate information on new CP phases so that a global fit could do more than extract SUSY mass information? David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
The pattern of deviation from the SM values is diagnostic David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
A Super B Factory is a DNA chip for New Physics David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
A new workshop will begin this Fall David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Conclusions: What is needed to make the case (my opinion) • My comments represent only my own point of view • I have some (limited) understanding of the situation in the US and Europe • I have even less understanding of the situation in Japan David Hitlin Super B Factory Workshop – Honolulu April 22, 2005
Conclusions: What is needed to make the case (my opinion) • A credible integrated luminosity capability approaching 10 ab-1/year • An accelerator with an upgrade path, as with the current B Factories • A detector that is conservatively designed and able to cope with backgroundsurprises and future luminosity upgrades • A credible plan for gathering a data sample of 10’s of ab-1 that allows the marquee important measurements to be made on a time scale that is competitive with LHCb and relevant to clarifying SUSY discoveries • An algorithm that there demonstrates the power of a real-time dialog between the LHC, a Super B Factory and, eventually, the ILC, would be a killer app • We have made real progress on this – more is needed • Discussions on forming a truly international collaboration on an appropriately scaled accelerator and detector • This would, for example, facilitate an ICFA endorsement • This could provide a critical mass of people and funding potential to convince the community that a Super B Factory should go forward David Hitlin Super B Factory Workshop – Honolulu April 22, 2005