Design of a 10CMS Super-B Factory *

2010

The SuperB project is an international effort aiming at building in Italy a very high luminosity e{sup +}e{sup -} (10{sup 36} cm{sup -2} sec{sup -1}) asymmetric collider at the Y(4S) energy in the CM. The accelerator design has been extensively studied and changed during the past year. The present design, based on the new collision scheme, with large Piwinski angle and the use of 'crab waist' sextupoles already successfully tested at the DA{Phi}NE {Phi}-Factory at LNF Frascati, provides larger flexibility, better dynamic aperture and spin manipulation sections in the Low Energy Ring (LER) for longitudinal polarization of the electron beam at the Interaction Point (IP). The Interaction Region (IR) has been further optimized in terms of apertures and reduced backgrounds in the detector. The injector complex design has been also updated. A summary of the project status will be presented in this paper. The SuperB collider can reach a peak luminosity of 10{sup 36} cm{sup -2} sec{...

2000

Parameters have been studied for a high luminosity e+e- collider operating at the Upsilon 4S that would deliver a luminosity of 1 to 4 x 10 36 /cm 2 /s. This collider, called a Super-B Factory, would use a combination of linear collider and storage ring techniques. In this scheme an electron beam and a positron beam are stored in

2005

This paper is based on the outcome of the activity that has taken place during the recent workshop on "SuperB in Italy" held in Frascati on November 11-12, 2005. The workshop was opened by a theoretical introduction of Marco Ciuchini and was structured in two working groups. One focused on the machine and the other on the detector and experimental issues. * The present status on CP is mainly based on the results achieved by BABAR and Belle. Estabilishment of the indirect CP violation in B sector in 2001 and of the direct CP violation in 2004 thanks to the success of PEP-II and KEKB e + e − asymmetric B Factories operating at the center of mass energy corresponding to the mass of the Υ(4S ). With the two B Factories taking data, the Unitarity Triangle is now beginning to be overconstrained by improving the measurements of the sides and now also of the angles α, and γ. We are also in presence of the very intriguing results about the measurements of sin2β in the time dependent analysis of decay channels via penguin loops, where b → sss and b → sdd. τ physics, in particular LFV search, as well as charm and ISR physics are important parts of the scientific program of a SuperB Factory. The physics case together with possible scenarios for the high luminosity SuperB Factory based on the concepts of the Linear Collider and the related experimental issues are discussed.

A Super Flavor Factory, an asymmetric energy e + ecollider with a luminosity of order 10 36 cm -2 s -1 , can provide a sensitive probe of new physics in the flavor sector of the Standard Model. The success of the PEP-II and KEKB asymmetric colliders [1,2] in producing unprecedented luminosity above 10 34 cm -2 s -1 has taught us about the accelerator physics of asymmetric e + ecolliders in a new parameter regime. Furthermore, the success of the SLAC Linear Collider [3] and the subsequent work on the International Linear Collider [4] allow a new Super-Flavor collider to also incorporate linear collider techniques. This note describes the parameters of an asymmetric Flavor-Factory collider at a luminosity of order 10 36 cm -2 s -1 at the Υ(4S) resonance and perhaps about 10 35 cm -2 s -1 at the τ production threshold. Such a collider would produce an integrated luminosity of about 10,000 fb -1 (10 ab -1 ) in a running year (10 7 sec) at the Υ(4S) resonance.

2009

The SuperB project aims at the construction of an asymmetric very high luminosity B-Factory on the Frascati/Tor Vergata (Italy) area, providing a uniquely sensitive probe of New Physics in the flavour sector of the Standard Model. The luminosity goal of 10 36 cm-2 s-1 can be reached with a new collision scheme with "large Piwinski angle" (LPA) and the use of "crab waist sextupoles" (CW) [1]. A LPA&CW Interaction Region (IR) has been successfully tested at the DA NE-Factory at LNF-Frascati in 2008 [2]. The LPA&CW scheme, together with very low *, will allow for operation with relatively low beam currents and reasonable bunch length, comparable to those of PEP-II and KEKB. In the High Energy Ring (HER), two spin rotators will bring longitudinally polarized beams into collision at the IP. The lattice has been designed with a very low intrinsic emittance and is quite compact, less than 2 km long. The tight focusing requires the final doublet quadrupoles to be very close to the IP and very compact. A Conceptual Design Report was published in March 2007 [3], and beam dynamics and collective effects R&D studies are in progress in order to publish a Technical Design Report by the end of 2010.

Progress of Theoretical and Experimental Physics, 2013

The SuperKEKB project requires a positron and electron collider with a peak luminosity of 8 × 10 35 cm −2 s −1. This luminosity is 40 times that of the KEKB B-factory, which operated for 11 years up to 2010. SuperKEKB is an asymmetry-energy and double-ring collider; the beam energy of the positron (LER) is 4 GeV and that of the electron (HER) is 7 GeV. An extremely small beta function at the interaction point (IP) and a low emittance are necessary. In addition, in order to achieve the target luminosity, a large horizontal crossing angle between two colliding beams is adopted, as is a bunch length much longer than the beta function at the IP. This method is called the "nano-beam scheme". The beam-beam parameter is assumed to be similar to KEKB, the beta function at the IP is 1/20, and the beam currents are twice those of KEKB in the nano-beam scheme. Consequently, the luminosity gain of 40 with respect to KEKB can be obtained.

2010

This report presents the results of studies that investigate the physics reach at a Super B factory, an asymmetric-energy e + e − collider with a design luminosity of 8 × 10 35 cm −2 s −1 , which is around 50 times as large as the peak luminosity achieved by the KEKB collider. The studies focus on flavor physics and CP violation measurements that could be carried out in the LHC era. The physics motivation, key observables, measurement methods and expected precisions are presented. 5.13.

Particle factories are facing their future by looking at the possibility of upgrading the luminosity by orders of magnitude. The upgrade challenges are more stringent at lower energies. Double symmetric rings, enhanced radiation damping, negative momentum compaction and very short bunches at the collision point are the main features of a \ -factory feasibility study presented in this paper. The bunch length of few millimetres at the crossing point of the beams is obtained by applying the Strong RF Focusing principle. The collider design fits the existing DAFNE infrastructures with completely rebuilt rings and upgraded injection system.

2014

The design of the SuperB B -Factory [1] has been inspiration for several other proposals and is the base of the SuperKEKB new design. SuperB was a state-of-the art accelerator for which new ideas were developed, such as the “Large Piwinski Angle and Crab Waist Sextupoles” (LPA&CW) collision scheme, super-squeezed beams, and polarized electron beam. The same design criteria were applied to a high luminosity Tau/Charm Factory designed by the INFN-LNF Laboratory in Frascati in collaboration with the Consortium Nicola Cabibbo Laboratory. The target luminosity is 10 35 cm -2 sec -1 at 4.6 GeV in the center of mass. The possibility to extend the Linac for a SASE-FEL facility was also taken into account. A Conceptual Design Report [2 ] was published in September 2013. Since the design of an intermediate energy e + e collider with high peak luminosity is still of interest for many laboratories worldwide, in this paper the design principles and the project features are summarized.

2013

After a decade of successful operation at KEKB a new asymmetric electron/positron collider, SuperKEKB, is being constructedupgradingKEKB. It aimsata luminosityof 8 × 10 35 cm −2 s −1 , 40-times higher than that of KEKB, in orderto studythe?avorphysicsof elementaryparticlesfurther, by mainly squeezing the beams at the collision point. The injector linac should provide high-intensity and lowemittance beams of 7-GeV electron and 4-GeV positron by newly installing a RF-gun, a?ux concentrator,and a damping ring with careful management of emittance and energy spread to be 20 mm.mrad and 0.1%. It should also perform simultaneous top-up injections into four storage rings by pulse-to-pulse beam modulations not to interfere between three facilities of SuperKEKB, Photon Factory and PF-AR. This paper describes the injector design decisions and present status of the construction. SuperKEKB will be commissioned within FY2014.