Slide1 : David Hitlin Super B Factory Workshop, Honolulu
April 22, 2004
Making an effective case for a Super B Factory : 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
EPP2010 : 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
The real world : 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
The real world : 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
Vulnerabilities : 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
Vulnerabilities, continued : 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
fKS (now) fKS 30 ab-1 Ciuchini, Franco, Martinelli, Masiero, & Silvestrini f23 mass insertion f13 mass insertion D ACP (J/ KS-p0KS) D ACP (J/ KS-fKS)
Vulnerabilities, continued : 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
Vulnerabilities, continued : 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 LHC A 50 ab-1 sample should be in hand as close to the middle of the next decade as is feasible
Strengths : 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
Scenarios for the next decade : 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
What can a Super B Factory bring to the party? : 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 and unique constraints 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 (t decays)
Higgs mediation (B Dtn, etc.)
Precision CKM Unitarity Triangle parameters
This is not news. How do we effectively demonstrate the impact of these measurements?
Scenarios for HEP in the next decade : Scenarios for HEP in the next decade LHC finds SUSY LHC turns on LHC doesn’t find SUSY We are here HEP What can the ILC say about
SUSY-breaking models? What can a
Super B Factory say about
SUSY-breaking models?
What will we learn about SUSY from the LHC? : 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
Exclusive studies are a game of edges and thresholds : 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
Correlations allow model discrimination : Correlations allow model discrimination
Third generation squark signatures : 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
The M( ) endpoint can be used to measure a combination of the squark masses.
The analysis requires as usual multiple hard jets and large ET plus two
jets tagged as b’s, two other jets not tagged as b’s and consistent with
Opposite sign, same flavor distributions also yield Dm’s : Opposite sign, same flavor distributions also yield Dm’s
Slide20 : There are also methods to get handles on combinations of the slepton mass, chargino masses, and perhaps, heavy gaugino masses and the spin
Ultimate precision on masses requires ILC : 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 scan to a precision ~100 MeV with 10 fb-1 per point
Combining LHC and ILC measurements (in >2020) : Combining LHC and ILC measurements (in >2020) Can extract all SUSY parameters: example SPS1a
Fittino
Squark mass matrix (d sector) : Squark mass matrix (d sector) LHC Super B Factory A Super B Factory, early in the LHC era, can provide the means to eliminate potential models as well as unique information on CP phases
Can we integrate Super B information into the SUSY program? : 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?
The pattern of deviation from the SM values is diagnostic : The pattern of deviation from the SM values is diagnostic
A Super B Factory is a DNA chip for New Physics : A Super B Factory is a DNA chip for New Physics
A new workshop will begin this Fall : A new workshop will begin this Fall
Conclusions: What is needed to make the case (my opinion) : 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
Conclusions: What is needed to make the case (my opinion) : 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 background surprises 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