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Tomassini, S

Publications and source records attributed to Tomassini, S.

9 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

The SuperB Project: Accelerator Status and R&D

The SuperB collider project has been recently approved by the Italian Government as part of the National Research Plan. SuperB is a high luminosity (10{sup 36} cm{sup -2} s{sup -1}) asymmetric e{sup +}e{sup -} collider at the {Upsilon}(4S) energy. The design is based on a 'large Piwinski angle and Crab Waist' scheme already successfully tested at the DAPHNE {Phi}-Factory in Frascati, Italy. The project combines the challenges of high luminosity colliders and state-of-the-art synchrotron light sources, such as two beams (e{sup +} at 6.7, HER, and e{sup -} at 4.2 GeV, LER) with extremely low emittances and small beam sizes at the Interaction Point. As unique features, the electron beam will be longitudinally polarized at the IP and the rings will be able to ramp down to collide at the {tau}/charm energy threshold with a luminosity of 10{sup 35} cm{sup -2} s{sup -1}. The relatively low beam currents (about 2 A) will allow for low running (power) costs compared to similar machines. The insertion of beam lines for synchrotron radiation (SR) users is the latest feature included in the design. The lattice has been recently modified to accommodate insertion devices for X-rays production.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

Site Studies for the SuperB Collider and Synchrotron Radiation Facility Project

The SuperB complex project aims at the construction of a very high luminosity (10{sup 36} cm{sup -2}s{sup -1}) asymmetric e{sup +}e{sup -} B-factory and a few X-ray synchrotron beam lines (SR). The project has been recently approved by the Italian Government as part of the National Research Plan. The Tor Vergata University location has been chosen and a Consortium among INFN, University of Rome II Tor Vergata and the Research Ministry is being signed, allowing for the constitution of the 'Cabibbo Laboratory', where the SuperB project will be hosted. This paper presents and describes the status of the preliminary design of the site layout, related issues for the chosen site and the preliminary ground motion (GM) measurement results.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

The SuperB Accelerator: Overview and Lattice Studies

SuperB aims at the construction of a very high luminosity (10{sup 36} cm{sup -2} s{sup -1}) asymmetric e{sup +}e{sup -} Flavour Factory, with possible location at the campus of the University of Rome Tor Vergata, near the INFN Frascati National Laboratory. In this paper the basic principles of the design and details on the lattice are given. SuperB is a new machine that can exploit novel very promising design approaches: (1) large Piwinski angle scheme will allow for peak luminosity of the order of 10{sup 36} cm{sup -2} s{sup -1}, well beyond the current state-of-the-art, without a significant increase in beam currents or shorter bunch lengths; (2) 'crab waist' sextupoles will be used for suppression of dangerous resonances; (3) the low beam currents design presents reduced detector and background problems, and affordable operating costs; (4) a polarized electron beam can produce polarized {tau} leptons, opening an entirely new realm of exploration in lepton flavor physics. SuperB studies are already proving useful to the accelerator and particle physics communities. The principle of operation is being tested at DAFNE. The baseline lattice, based on the reuse of all PEP-II hardware, fits in the Tor Vergata University campus site, near Frascati. A CDR is being reviewed by an International Review Committee, chaired by J. Dainton (UK). A Technical Design Report will be prepared to be ready by beginning of 2010.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

Design of a 10**36 CM-2 S-1 Super-B Factory

Parameters have been studied for a high luminosity e{sup +}e{sup -} collider operating at the Upsilon 4S that would deliver a luminosity of 1 to 4 x 10{sup 36}/cm{sup 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 low-emittance damping rings similar to those designed for a Linear Collider (LC) or the next generation light source. A LC style interaction region is included in the ring to produce sub-millimeter vertical beta functions at the collision point. A large crossing angle (+/- 24 mrad) is used at the collision point to allow beam separation. A crab-waist scheme is used to reduce the hourglass effect and restore peak luminosity. Beam currents of 1.8 A at 4 x 7 GeV in 1251 bunches can produce a luminosity of 10{sup 36}/cm{sup 2}/s with upgrade possibilities. Such a collider would produce an integrated luminosity of about 10,000 fb{sup -1} (10 ab{sup -1}) in a running year (10{sup 7} sec) at the {gamma}(4S) resonance. Further possibilities include having longitudinally polarized e- at the IR and operating at the J/Psi and Psi beam energies.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

The Super-B Project Accelerator Status

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{sup -1} with beam currents and bunch lengths similar to those of the past and present e{sup +}e{sup -} Factories, through the use of smaller emittances and new scheme of crossing angle collision. The beams are stored in two rings at 6.7 GeV (HER) and 4.2 GeV (LER). Unique features of the project are the polarization of the electron beam in the LER and the possibility to decrease the energies for running at the {tau}/charm threshold. The option to reuse the PEP-II B-Factory (SLAC) hardware will allow reducing costs. The SuperB facility will require a big complex of civil infrastructure. The main construction, which will house the final part of the LINAC, the injection lines, the damping rings, and the storage rings, will be mainly underground. Two sites have been considered: the campus of Tor Vergata University near Frascati, and the INFN Frascati Laboratory. No decision has been made yet. A footprint of the possible SuperB layout on the LNF area is shown in Fig. 1.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

Vibration Budget for SuperB

We present a vibration budget for the SuperB accelerator. We include ground motion data, motion sensitivity of machine components, and beam feedback system requirements. The SuperB accelerator design attains at least 50 times higher than current B-factories due to smaller beam sizes and a crabbed waist crossing angle scheme at the IP (interaction point). The beam size (1{sigma}) at the IP will be about 10 {micro}m (horizontal) by 40 nm (vertical). These small beam sizes will make the luminosity very sensitive to mechanical vibration and electrical noise. Relative vertical misalignment of the two beams at the IP by only 8 nm will result in a 1% reduction in luminosity. The corresponding horizontal alignment tolerance of is 250x looser (2 {micro}m). The vertical beam angle at the IP for a 1% luminosity loss is fairly loose at 200 {micro}rad, and the horizontal beam angle tolerance is looser still. We will focus on vertical beam position at the IP, since this presents the greatest alignment challenge. The values presented here are for a closed orbit with tunes near a half-integer in the SuperB v.12 lattice.

43 PARTICLE ACCELERATORS↗
DOE OSTI2010

Super-B Project Overview

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{sup 36} cm{sup -2} s{sup -1} can be reached with a new collision scheme with 'large Piwinski angle' (LPA) and the use of 'crab waist sextupoles' (CW). A LPA&CW Interaction Region (IR) has been successfully tested at the DA{Phi}NE {Phi}-Factory at LNF-Frascati in 2008. The LPA&CW scheme, together with very low {beta}*, 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, 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.

43 PARTICLE ACCELERATORS↗