Recent Applications Of Hamiltonian Dynamics To Accelerator Physics (2008)
this paper we outline the normal form theory for magnetic lattices, pointing out applications such as the computation of the quantities which characterize the nonlinear motion and the analytical...
Normal Forms And Invariants In The Description Of A Magnetic Lattice (2008)
Armando Bazzani, Graziano Servizi, Ezio Todesco, Giorgio Turchetti
this paper is twofold: we review some applications of the non resonant normal form to present and future machines and we outline three different methods to extend the validity limits of the normal...
Bellesia, B, Todesco, Ezio, Santoni, Claudio
The homogeneity of the magnetic field in the LHC dipoles strongly depends on the correct position of the superconducting cables: this is related to the quality of the dipole components, such as the...
Electromagnetic Design of Superconducting Dipoles Based on Sector Coils (2007)
We study the coil lay-outs of superconducting dipoles for particle accelerators based on the sector geometry. We show that a simple model based on a sector coil with a wedge allows us to derive an...
. A generalization of the H`enon map is discussed; such a model arises in a natural way from the extrapolation of the multipolar errors of the superconducting dipoles of the planned Large Hadron...
Massimo Giovannozzi, O Bazzani, Graziano Servizi, Ezio Todesco, Giorgio Turchetti
We consider the conservative H'enon mapping, which is the one dimensional model of a FODO cell with a sextupole nonlinearity. We analyse the well known problem of estimating the dynamic aperture...
Resonant Normal Forms And Applications To Beam Dynamics (2007)
Graziano Servizi, Ezio Todesco
this paper we review some of these results; in Section 2 we introduce the simplest nontrivial model (conservative H'enon map
Parametric Analysis of Forces and Stresses in Superconducting Quadrupole Sector Windings (2007)
Fessia, Paolo, Regis, Federico, Todesco, Ezio
This paper presents a review of the existing analytical approximations of the magnetic field of a sector winding quadrupole, evaluating to which extent these formulae are usable as a first estimation...
An Estimate of the Maximum Gradients in Superconducting Quadrupoles (2007)
In this paper we show that the electromagnetic design of several superconducting quadrupoles, built for particle accelerators, can be rather well approximated by a 36 degree sector coil with a wedge,...
Performance of LHC Main Dipoles for Beam Operation (2006)
De Rijk, Gijsbert, Bajko, Marta, Bottura, Luca, Buzio, Marco Carlo Luigi, Chohan, Vinod, Deniau, Laurent, ...
At present about 90% of the main dipoles for the LHC have been manufactured and one of the three cold mass assemblers has already completed the production. 85% of the 1232 dipoles needed for the...
In this report we analyse the correlations between magnetic measurements at room temperature and at 1.9 K for the main LHC quadrupoles. Most of the work is devoted to the correction of room...
In this report we analyse the correlations between magnetic measurements at room temperature and at 1.9 K for the main LHC quadrupoles. Most of the work is devoted to the correction of room...
Bellesia, B, Bottura, L, Granata, V, Le Naour, S, Oberli, L, Sanfilippo, S, ...
The production of more than 60% of superconducting cables for the main dipoles of the Large Hadron Collider has been completed. The results of the measurements of cable magnetization and the...
Sanfilippo, S, Bottura, L, Calvi, M, Chohan, V, Durante, M, Hagen, P, ...
The series testing at 1.9 K of the 360 Short Straight Sections (SSS) for the Large Hadron Collider have started at CERN in September 2003. The SSS contain the lattice quadrupoles and correction...
Bellesia, B, Bottura, L, Granata, V, Le Naour, S, Oberli, L, Sanfilippo, S, ...
The production of more than 60% of superconducting cables for the main dipoles of the Large Hadron Collider has been completed. The results of the measurements of cable magnetization and the...
Sanfilippo, S, Bottura, L, Calvi, M, Chohan, V, Durante, M, Hagen, P, ...
The series testing at 1.9 K of the 360 Short Straight Sections (SSS) for the Large Hadron Collider have started at CERN in September 2003. The SSS contain the lattice quadrupoles and correction...
The ITER project: technological challenges (2004)
Bruzzone, P L, Lister, Joseph, Marquina, Miguel A, Todesco, Ezio
The first lecture reminds us of the ITER challenges, presents hard engineering problems, typically due to mechanical forces and thermal loads and identifies where the physics uncertainties play a...
A Strategy for Sampling the Field Quality of the LHC Dipoles (2004)
Bottura, L, Granata, V, Fartoukh, Stéphane David, Todesco, Ezio
We have measured the magnetic field of a large fraction of the LHC main dipoles, to date more than 400 in warm conditions and over 100 in cold conditions. Using the available data we analysed the...
A Strategy for Sampling the Field Quality of the LHC Dipoles (2004)
Bottura, L, Granata, V, Fartoukh, Stéphane David, Todesco, Ezio
We have measured the magnetic field of a large fraction of the LHC main dipoles, to date more than 400 in warm conditions and over 100 in cold conditions. Using the available data we analysed the...
Wildner, E, Pauletta, S, Remondino, V, Scandale, Walter, Todesco, Ezio, Völlinger, C
In this paper we review the tools used for controlling the production of the LHC main dipoles through warm magnetic measurements. For the collared coil measurements, control limits are based on the...
Steering field quality in the main dipole magnets of the Large Hadron Collider (2004)
Todesco, Ezio, Bellesia, B, Bottura, L, Devred, Arnaud, Remondino, Vittorio, Pauletta, S, ...
More than 10% of the collared coils of the main LHC dipoles have been produced. In this paper we compare the measured field quality to beam dynamics targets using correlations to measurements at...
Bellesia, B, Remondino, V, Scandale, Walter, Todesco, Ezio, Völlinger, C
The Large Hadron Collider (LHC) [1], a proton-proton superconducting accelerator, will consist of about 8400 superconducting magnet units, all operating in superfluid helium at a temperature of...
Wildner, E, Pauletta, S, Remondino, Vittorio, Scandale, Walter, Todesco, Ezio, Völlinger, C
In this paper we review the tools used for controlling the production of the LHC main dipoles through warm magnetic measurements. For the collared coil measurements, control limits are based on the...
Steering field quality in the main dipole magnets of the Large Hadron Collider (2004)
Todesco, Ezio, Bellesia, B, Bottura, L, Devred, Arnaud, Remondino, Vittorio, Pauletta, S, ...
More than 10% of the collared coils of the main LHC dipoles have been produced. In this paper we compare the measured field quality to beam dynamics targets using correlations to measurements at...
Bellesia, B, Remondino, Vittorio, Scandale, Walter, Todesco, Ezio, Völlinger, C
The Large Hadron Collider (LHC) [1], a proton-proton superconducting accelerator, will consist of about 8400 superconducting magnet units, all operating in superfluid helium at a temperature of...
Influence of Superconducting Cable Dimensions on Field Harmonics in the LHC Main Dipole (2004)
Bellesia, B, Scandale, Walter, Todesco, Ezio
The quality of the magnetic field in the LHC main dipoles is given by the correct location and dimensions of the superconducting cables. In this paper the measurements of the dimensions of the LHC...
The result of the magnetic measurements after the cold mass assembly is a holding point for the production of the LHC main dipoles. Here we describe how the magnetic measurements are screened to...
Status of the LHC Main Dipole Pre-Series Production (2003)
Modena, M, Bajko, M, Cornelis, M, Fessia, P, Miles, J, Pugnat, P, ...
The procurement of a pre-series of 90 main dipoles was decided as the first step towards the series production of 1232 arc main dipoles within the LHC magnet program. The pre-series production is...
Controlling Field Quality in Magnet Production (2003)
Scandale, Walter, Bottura, L, Devred, Arnaud, Remondino, Vittorio, Sanfilippo, S, Todesco, Ezio, ...
The field quality measurements at room temperature of around 100 collared coils of the main LHC dipoles are analysed. Using correlations to field measurements at 1.9 K, comparison with beam dynamics...
Status of the LHC Main Dipole Pre-Series Production (2003)
Modena, M, Bajko, M, Cornelis, M, Fessia, P, Miles, J, Pugnat, P, ...
The procurement of a pre-series of 90 main dipoles was decided as the first step towards the series production of 1232 arc main dipoles within the LHC magnet program. The pre-series production is...
Controlling Field Quality in Magnet Production (2003)
Scandale, Walter, Bottura, L, Devred, Arnaud, Remondino, Vittorio, Sanfilippo, S, Todesco, Ezio, ...
The field quality measurements at room temperature of around 100 collared coils of the main LHC dipoles are analysed. Using correlations to field measurements at 1.9 K, comparison with beam dynamics...
Inluence of Copper Wedge Dimensions on Field Harmonics in the Main LHC Dipoles (2003)
Bellesia, B, Bertinelli, F, Fessia, P, Gubello, G, Lanza, C, Scandale, Walter, ...
In order to obtain the required magnetic field quality in the LHC main dipole, the superconductive cables blocks are separated by copper wedges. These components must respect geometrical...
In superconducting accelerator magnets, the field quality is mainly determined by conductor position inside the coil. For the LHC, the dipolar field homogeneity must be assured up to 10-5 of the main...
In superconducting accelerator magnets, the field quality is mainly determined by conductor position inside the coil. For the LHC, the dipolar field homogeneity must be assured up to 10-5 of the main...
A Method to Determine the Flexural Rigidity of the Main Dipole for the Large Hadron Collider (2003)
La China, M, Cavallari, Giorgio, Ferracin, P, García-Pérez, J, Todesco, Ezio, Scandale, Walter
The Large Hadron Collider (LHC) superconducting dipole cold mass is a cylindrical structure 15 m long, made of a shrinking cylinder which contains iron laminations and collared coils. This structure,...
An Estimate of Multipolar Errors in the LHC Dipoles (2003)
Todesco, Ezio, Bottura, L, Remondino, Vittorio, Sanfilippo, S, Scandale, Walter
Magnetic measurements of 60 collared coils and of 14 cryomagnets are available for the LHC dipoles. These data are used to work out an estimate of the systematic and random components of the field...
A Method to Determine the Flexural Rigidity of the Main Dipole for the Large Hadron Collider (2003)
La China, M, Cavallari, Giorgio, Ferracin, P, García-Pérez, J, Todesco, Ezio, Scandale, Walter
The Large Hadron Collider (LHC) superconducting dipole cold mass is a cylindrical structure 15 m long, made of a shrinking cylinder which contains iron laminations and collared coils. This structure,...
Status Report on Field Quality in the Main LHC Dipoles (2002)
Bottura, L, Todesco, Ezio, Scandale, Walter, Sanfilippo, S, Remondino, V, Pauletta, S
We give the present status of the field quality in the main LHC dipoles. Special emphasis is given to the collared coil data: a few tens of coils have been built, allowing a first analysis of the...
Status Report on Field Quality in the Main LHC Dipoles (2002)
Bottura, L, Pauletta, S, Remondino, Vittorio, Sanfilippo, S, Scandale, Walter, Todesco, Ezio
We give the present status of the field quality in the main LHC dipoles. Special emphasis is given to the collared coil data: a few tens of coils have been built, allowing a first analysis of the...
Bottura, L, Todesco, Ezio, Scandale, Walter, Savary, F, Sanfilippo, S, Remondino, V, ...
In this paper we discuss even multipolar components of the Large Hadron Collider dipole in relation to the manufacturing features and target values required by beam dynamics. Due to the two-in-one...
Bottura, L, Redaelli, S, Remondino, Vittorio, Sanfilippo, S, Savary, F, Scandale, Walter, ...
In this paper we discuss even multipolar components of the Large Hadron Collider dipole in relation to the manufacturing features and target values required by beam dynamics. Due to the two-in-one...
Field quality of the LHC dipole magnets in operating conditions (2002)
Bottura, L, Buzio, M, Fartoukh, Stéphane David, Russenschuck, Stephan, Sanfilippo, S, Scandale, Walter, ...
We report here the main results of the field measurements performed so far on the pre-series LHC superconducting dipoles at superfluid helium temperature. After discussing the results at injection...
Geometrical position of the Large Hadron Collider main dipole inside the cryostat (2002)
La China, M, García-Pérez, J, Gubello, G, Hauviller, Claude, Scandale, Walter, Todesco, Ezio
The superconducting dipole of the Large Hadron Collider (LHC) is a cylindrical structure made of a shrinking cylinder containing iron laminations and collared coils. This 15 m long structure,...
Field quality in the ends of the Large Hadron Collider main dipole (2002)
Schiappapietra, A, Todesco, Ezio, Remondino, V, Fessia, P
Magnetic field measurements are an important tool to monitor the LHC main dipole production. In this paper we analyse the data relative to a few tens of collared coils produced for the pre-series...
Field quality of the LHC dipole magnets in operating conditions (2002)
Bottura, L, Buzio, M, Fartoukh, Stéphane David, Russenschuck, Stephan, Sanfilippo, S, Scandale, Walter, ...
We report here the main results of the field measurements performed so far on the pre-series LHC superconducting dipoles at superfluid helium temperature. After discussing the results at injection...
Schiappapietra, A, Fessia, P, Remondino, Vittorio, Todesco, Ezio
Magnetic field measurements are an important tool to monitor the LHC main dipole production. In this paper we analyse the data relative to a few tens of collared coils produced for the pre-series...
Geometrical position of the Large Hadron Collider main dipole inside the cryostat (2002)
La China, M, García-Pérez, J, Gubello, G, Hauviller, Claude, Scandale, Walter, Todesco, Ezio
The superconducting dipole of the Large Hadron Collider (LHC) is a cylindrical structure made of a shrinking cylinder containing iron laminations and collared coils. This 15 m long structure,...
High Precision Displacement Measurement Using Fiber Optics (2002)
Berkovic, G, Rotter, S, Scandale, Walter, Shafir, E, Todesco, Ezio
We describe laboratory experiments with a fiber-optic sensor employing a chirped laser that detects, with 20-30 micrometer accuracy, displacements of a remote reflective target at distance of 200-500...
Aleksa, Martin, Amet, S, Ang, Z, Bottura, L, Buzio, M, Ferracin, P, ...
We report the main results of the magnetic field measurements performed on the full-size LHC superconducting dipoles tested at CERN since summer 1998. Main field strength and field errors are...
Aleksa, Martin, Amet, S, Ang, Z, Bottura, L, Buzio, M, Ferracin, P, ...
We report the main results of the magnetic field measurements performed on the full-size LHC superconducting dipoles tested at CERN since summer 1998. Main field strength and field errors are...
Ferracin, P, Scandale, Walter, Todesco, Ezio, Tommasini, D
We describe a finite element mechanical model of the main LHC dipole, based on the geometry and on the properties of its components; coil characteristics are derived from measurements on stacks of...
Optical In-Situ Measurement of Relative Deformations of the LHC Main Dipole Cold Masses (2002)
Aznar, S, Billan, J, García-Pérez, J, La China, M, Ferracin, P, Redaelli, S, ...
The LHC cryodipoles are composed of an evacuated cryostat and a cold mass, which is cooled by superfluid helium at 1.9 K. To obey constraints imposed by beam dynamics the particle beams must be...
Impact of Coil Deformations on Field Quality in the Large Hadron Collider Main Dipole (2002)
Ferracin, P, Pagano, O, Remondino, Vittorio, Scandale, Walter, Todesco, Ezio, Tommasini, D
In superconducting accelerator magnets the coils are usually pre-stressed in order to avoid conductor movements induced by electro-magnetic forces. In this paper we use a finite element mechanical...
Ferracin, P, Rastogi, P K, Scandale, Walter, Todesco, Ezio, Tropea, P
Magnetic field quality in superconducting magnets mostly depends on conductor position in operational conditions (under pressure, at 1.9 K). For the case of the LHC main magnets, the conductor layout...
Impact of Coil Deformations on Field Quality in the Large Hadron Collider Main Dipole (2002)
Ferracin, P, Pagano, O, Remondino, Vittorio, Scandale, Walter, Todesco, Ezio, Tommasini, D
In superconducting accelerator magnets the coils are usually pre-stressed in order to avoid conductor movements induced by electro-magnetic forces. In this paper we use a finite element mechanical...
Ferracin, P, Scandale, Walter, Todesco, Ezio, Tommasini, D
We describe a finite element mechanical model of the main LHC dipole, based on the geometry and on the properties of its components; coil characteristics are derived from measurements on stacks of...
Optical In-Situ Measurement of Relative Deformations of the LHC Main Dipole Cold Masses (2002)
Aznar, S, Billan, J, García-Pérez, J, La China, M, Ferracin, P, Redaelli, S, ...
The LHC cryodipoles are composed of an evacuated cryostat and a cold mass, which is cooled by superfluid helium at 1.9 K. To obey constraints imposed by beam dynamics the particle beams must be...
Elastic Modulus Measurements of the LHC Dipole Superconducting Coil at 300 K and at 77 K (2001)
Couturier, K, Ferracin, P, Todesco, Ezio, Tommasini, D, Scandale, Walter
We present measurements of the stress-displacement relation for the superconducting coils used in the Large Hadron Collider main magnets (dipoles and quadrupoles). This mechanical property is...
Elastic Modulus Measurements of the LHC Dipole Superconducting Coil at 300 K and at 77 K (2001)
Couturier, K, Ferracin, P, Todesco, Ezio, Tommasini, D, Scandale, Walter
We present measurements of the stress-displacement relation for the superconducting coils used in the Large Hadron Collider main magnets (dipoles and quadrupoles). This mechanical property is...
Geometric and Magnetic Axes of the LHC Dipole (2001)
Bajko, M, Billan, J, Buzio, M, Deferne, G, Ferracin, P, García-Pérez, J, ...
The 15-m long superconducting dipoles of the Large Hadron Collider (LHC) with two-in-one design are curved by about 5 mrad to follow the beam trajectory. They are supported on three cold feet to...
Modena, M, Bajko, M, Bottura, L, Buzio, M, Fessia, P, Pagano, O, ...
The LHC, a 7 TeV proton collider presently under construction at CERN, requires 1232 superconducting dipole magnets, featuring a nominal field of 8.33 T inside a cold bore tube of 50 mm inner...
Modena, M, Bajko, M, Bottura, L, Buzio, M, Fessia, P, Pagano, O, ...
The LHC, a 7 TeV proton collider presently under construction at CERN, requires 1232 superconducting dipole magnets, featuring a nominal field of 8.33 T inside a cold bore tube of 50 mm inner...
Geometric and Magnetic Axes of the LHC Dipole (2001)
Bajko, M, Billan, J, Buzio, M, Deferne, G, Ferracin, P, García-Pérez, J, ...
The 15-m long superconducting dipoles of the Large Hadron Collider (LHC) with two-in-one design are curved by about 5 mrad to follow the beam trajectory. They are supported on three cold feet to...
Control of field quality for the production of the main LHC dipoles (2001)
Ferracin, P, Pagano, O, Redaelli, S, Scandale, Walter, Todesco, Ezio
We review the warm magnetic measurements of the first four main dipole prototypes (8 apertures) and their agreement with nominal design. We then estimate the order of magnitude of the corrections...
Ferracin, P, Scandale, Walter, Todesco, Ezio, Wolf, R
Estimates of random field-shape errors induced by cable mispositioning in superconducting magnets are presented and specific applications to the Large Hadron Collider (LHC) main dipoles and...
Ferracin, P, Scandale, Walter, Todesco, Ezio, Wolf, R
Estimates of random field-shape errors induced by cable mispositioning in superconducting magnets are presented and specific applications to the Large Hadron Collider (LHC) main dipoles and...
Ferracin, P, Scandale, Walter, Todesco, Ezio, Tropea, P, Vanenkov, I
The mechanical structure of the main LHC dipole is analysed. A finite element model is used to estimate the loads and the deformations at cryogenic temperature. The correct setting of the model...
Peyrot, M, Redaelli, S, Remondino, V, Rifflet, J M, Scandale, Walter, Simon, F, ...
The room temperature magnetic measurements of the first series-design prototypes of the LHC main quadrupoles are analysed. Data relative to the collared coils and to the assembled cold mass are...
Manufacture and Performance of the LHC Main Dipole Final Prototypes (2000)
Modena, M, Artoos, K, Bajko, M, Bottura, L, Buzio, M, Fessia, P, ...
This paper reports about the program of six LHC main dipole final prototypes. This program, launched in summer 1998, relies on industrially manufactured collared coils and cold masses assembled at...
Ferracin, P, Scandale, Walter, Todesco, Ezio, Tropea, P, Vanenkov, I
The mechanical structure of the main LHC dipole is analysed. A finite element model is used to estimate the loads and the deformations at cryogenic temperature. The correct setting of the model...
Peyrot, M, Redaelli, S, Remondino, Vittorio, Rifflet, J M, Scandale, Walter, Simon, F, ...
The room temperature magnetic measurements of the first series-design prototypes of the LHC main quadrupoles are analysed. Data relative to the collared coils and to the assembled cold mass are...
Manufacture and Performance of the LHC Main Dipole Final Prototypes (2000)
Modena, M, Artoos, K, Bajko, M, Bottura, L, Buzio, M, Fessia, P, ...
This paper reports about the program of six LHC main dipole final prototypes. This program, launched in summer 1998, relies on industrially manufactured collared coils and cold masses assembled at...
Magnetic errors of the LHC dipoles and possible cures (2000)
Bartolini, R, Fessia, P, Perini, D, Scandale, Walter, Todesco, Ezio
Random Errors induced by the Superconducting Windings in the LHC Dipoles (1999)
Scandale, Walter, Todesco, Ezio, Wolf, R
The problem of estimating the random errors in the LHC dipole is considered. The main contributions to random errors are due to random displacements of the coil position with respect to nominal...
Artoos, K, Bottura, L, Fessia, P, Bajko, M, Modena, M, Pagano, O, ...
This paper reports about the program of six LHC superconducting main dipole final prototypes and the steps towards series manufacture. The above program, launched in summer 1998, relies on collared...
A Method to Measure Thermal Deformation of Superconducting Magnet Cross Sections (1999)
Grau-Carles, A, García-Tabarés, L, Todesco, Ezio, Tommasini, D, Siegel, N
The precision measurement of the cable positioning in superconducting coils is of great interest both at room and liquid nitrogen temperatures because mechanical and thermal deformations affect the...
Analysis of Warm Magnetic Measurements in a LHC Main Dipole Prototype (1999)
Gleis, S, Miles, J, Pagano, O, Scandale, Walter, Todesco, Ezio
The data relative to the magnetic measurements at room temperature of the MBP2N1 prototype of the LHC dipole are presented. The measured field harmonics are compared to the results of the numerical...
Influence of Mechanical Tolerances on Field Quality in the LHC Main Dipoles (1999)
Scandale, Walter, Todesco, Ezio, Tropea, P
We evaluate the influence of mechanical tolerances on the field quality in the LHC dipoles. We show that the most relevant effect is due to tolerances on the coil and on the internal part of the...
Influence of Mechanical Tolerances on Field Quality in the LHC Main Dipoles (1999)
Scandale, Walter, Todesco, Ezio, Tropea, P
We evaluate the influence of mechanical tolerances on the field quality in the LHC dipoles. We show that the most relevant effect is due to tolerances on the coil and on the internal part of the...
Analysis of Warm Magnetic Measurements in a LHC Main Dipole Prototype (1999)
Gleis, S, Miles, J, Pagano, O, Scandale, Walter, Todesco, Ezio
The data relative to the magnetic measurements at room temperature of the MBP2N1 prototype of the LHC dipole are presented. The measured field harmonics are compared to the results of the numerical...
Random Errors induced by the Superconducting Windings in the LHC Dipoles (1999)
Scandale, Walter, Todesco, Ezio, Wolf, R
The problem of estimating the random errors in the LHC dipole is considered. The main contributions to random errors are due to random displacements of the coil position with respect to nominal...
Artoos, K, Bottura, L, Fessia, P, Bajko, M, Modena, M, Pagano, O, ...
This paper reports about the program of six LHC superconducting main dipole final prototypes and the steps towards series manufacture. The above program, launched in summer 1998, relies on collared...
A Method to Evaluate the Field-Shape Multipoles Induced by Coil Deformations (1999)
Ferracin, P, Scandale, Walter, Todesco, Ezio, Tropea, P
A semi-analytical method to evaluate the effect of coil de-formations on the field-shape imperfections of the LHC dipole is presented. The deformation induced by the collaring procedure and by the...
Field Shape Variation Induced by Thermal Cycling and Excitation in the LHC Dipole (1999)
Pagano, O, Scandale, Walter, Todesco, Ezio
The field-shape imperfections measured at room temperature before and after thermal cycling and excitation up to maximum field in three 10 m-long models of the LHC dipole are presented. A systematic...
A Method to Evaluate the Field-Shape Multipoles Induced by Coil Deformations (1999)
Ferracin, P, Scandale, Walter, Todesco, Ezio, Tropea, P
A semi-analytical method to evaluate the effect of coil de-formations on the field-shape imperfections of the LHC dipole is presented. The deformation induced by the collaring procedure and by the...
Field Shape Variation Induced by Thermal Cycling and Excitation in the LHC Dipole (1999)
Pagano, O, Scandale, Walter, Todesco, Ezio
The field-shape imperfections measured at room temperature before and after thermal cycling and excitation up to maximum field in three 10 m-long models of the LHC dipole are presented. A systematic...
Overview of Single-particle Nonlinear Dynamics (1999)
We give an overview of the single-particle non linear dynamics in circular accelerators. The main topics are: integration of equations of motion, fast symplectic tracking, dynamic aperture...
Scandale, Walter, Bartolini, R, Ferracin, P, Fessia, P, Todesco, Ezio
The stability of the geometry of the superconducting coils is essential to the field homogeneity of the LHC dipole magnets. Mechanical stresses during coil assembly, thermal stresses during cool-down...
Long term estimates for sorting strategies of the LHC dipoles (1998)
Scandale, Walter, Bartolini, R, Giovannozzi, Massimo, Todesco, Ezio
Sorting strategies are investigated in view of improving the dynamic aperture of the CERN-LHC. Local and quasi-local compensation of the random field shape imperfections are discussed and applied to...
Scandale, Walter, Todesco, Ezio
The problem of long-term losses in hadron colliders such as the Large Hadron Collider (LHC) is considered. A previous formula that provides the reduction of dynamic aperture with the number of turns...
Scandale, Walter, Bartolini, R, Ferracin, P, Fessia, P, Todesco, Ezio
The stability of the geometry of the superconducting coils is essential to the field homogeneity of the LHC dipole magnets. Mechanical stresses during coil assembly, thermal stresses during cool-down...
Scandale, Walter, Todesco, Ezio
The problem of long-term losses in hadron colliders such as the Large Hadron Collider (LHC) is considered. A previous formula that provides the reduction of dynamic aperture with the number of turns...
Long term estimates for sorting strategies of the LHC dipoles (1998)
Scandale, Walter, Bartolini, R, Giovannozzi, Massimo, Todesco, Ezio
Sorting strategies are investigated in view of improving the dynamic aperture of the CERN-LHC. Local and quasi-local compensation of the random field shape imperfections are discussed and applied to...
NERO: a code for evaluation of nonlinear resonances in 4D symplectic mappings (1998)
Todesco, Ezio, Gemmi, M, Giovannozzi, Massimo
A code to evaluate the stability, the position and the width of nonlinear resonances in four-dimensional symplectic mappings is described. NERO is based on the computation of the resonant...
Normal Form Analysis of the LHC Dynamic Aperture (1997)
Normal form is a well developed tool to study the nonlinear dynamics of even the most complicated structures. This can become particularly useful in the design of large nonlinear hadron colliders...
Normal Form Analysis of the LHC Dynamic Aperture (1997)
Normal form is a well developed tool to study the nonlinear dynamics of even the most complicated structures. This can become particularly useful in the design of large nonlinear hadron colliders...
Scaling Laws for Dynamic Aperture due to Chromatic Sextupoles (1997)
Scandale, Walter, Todesco, Ezio
Scaling laws for the dynamic aperture due to chromatic sextupoles are investigated. The problem is addressed in a simplified lattice model containing 4 N identical cells and one linear betatron phase...
Numerical Evaluation of long-term Stability (1997)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
The problem of predicting long-term particle loss in 4D betatronic motion is considered. A phenomenological scenario is derived through numerical tools based on tracking and frequency analysis. A...
Dynamic Aperture Extrapolation in Presence of Tune Modulation (1997)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
In hadron colliders, such as the Large Hadron Collider (LHC) to be built at CERN, the long-term stability of the single-particle motion is mostly determined by the field-shape quality of the...
Numerical Evaluation of long-term Stability (1997)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
The problem of predicting long-term particle loss in 4D betatronic motion is considered. A phenomenological scenario is derived through numerical tools based on tracking and frequency analysis. A...
Dynamic Aperture Extrapolation in Presence of Tune Modulation (1997)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
In hadron colliders, such as the Large Hadron Collider (LHC) to be built at CERN, the long-term stability of the single-particle motion is mostly determined by the field-shape quality of the...
PLATO: A Program Library for the Analysis of 4D Nonlinear Transverse Motion (1997)
Giovannozzi, Massimo, Todesco, Ezio, Bazzani, A, Bartolini, R
The PLATO (Perturbative Lattice Analysis and Tracking tOols) program, a program library for analyzing four-dimensional betatronic motion in circular particle accelerators is presented. The routines...
Inverse logarithm decay of long-term dynamic aperture in hadron colliders (1997)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
The long-term behaviour of the non-linear single-particle dynamic aperture is considered for the 4D Henon map. The dynamic aperture is defined as the average of the particle loss boundary over...
Summary report of the group on single-particle nonlinear dynamics (1997)
Axinescu, S, Bartolini, R, Bazzani, A, Biagini, M E, Chao, A, Dragt, A, ...
PLATO: a program library for the analysis of nonlinear betatronic motion (1996)
Giovannozzi, Massimo, Todesco, Ezio, Bazzani, A, Bartolini, R
Proposal of a Sorting Experiment at the CERN SPS (1996)
Bartolini, R, Giovannozzi, Massimo, Todesco, Ezio, Scandale, Walter
We propose to study the effectiveness of the sorting strategies on the CERN SPS using eight strong extraction sextupoles independently powered to simulate random errors. In order to find the best...
Early indicators of long term stability in hadron colliders (1996)
Bartolini, R, Faus-Golfe, A, Giovannozzi, Massimo, Todesco, Ezio, Scandale, Walter
Early indicators of long-term stability, based on short-term tracking data, are considered in hadron colliders, such as the CERN-LHC. Two early indicators are analysed: the Lyapunov coefficient and...
Test of the Sorting Methods at the CERN-SPS (1996)
Bartolini, R, Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
An external study of the effectiveness of the sorting strategies on the CERN Super-Proton-Synchrotron is proposed. The eight strong extraction sextupoles used for diffusion experiments can be...
Evaluating High Order resonances using Resonant Normal Forms (1996)
Resonant normal forms allow to study various aspects of resonances up to high orders. We apply these techniques to evaluate resonances in four phase space variables. The input is truncated one-turn...
Algorithms for a Precise Determination of the Betatron Tune (1996)
Bartolini, R, Bazzani, A, Giovannozzi, Massimo, Todesco, Ezio, Scandale, Walter
In circular accelerators the precise knowledge of the betatron tune is of paramount importance both for routine operation and for theoretical investigations. The tune is measured by sampling the...
Evaluation of Dynamic Aperture in the Presence of Phase Space Distortions (1996)
Todesco, Ezio, Giovannozzi, Massimo, Scandale, Walter
We study symplectic mappings which occur in the modelization of the 4D betatronic motion in a magnetic lattice and define the dynamic aperture in terms of the connected volume in phase space of...
Measurements of the Tune Variations Induced by Non-Linearities in Lepton Machines (1996)
Bartolini, R, Corbett, J, Cornacchia, M, Giovannozzi, Massimo, Pellegrini, C, Scandale, Walter, ...
The precise measurement of the betatron tune as a function of the oscillation amplitude provides a useful information on non-linear beam dynamics. In lepton accelerators, this measurement is made...
Prediction of Long-Term Stability in Large Hadron Colliders (1996)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
Short-term tracking data are used to compute early indicators of long-term stability in large hadron colliders. A phenomenological picture of the mechanisms that lead to long-term particle loss is...
Prediction of Long-Term Stability in Large Hadron Colliders (1996)
Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
Short-term tracking data are used to compute early indicators of long-term stability in large hadron colliders. A phenomenological picture of the mechanisms that lead to long-term particle loss is...
Tune evaluation in simulations and experiments (1995)
Bartolini, R, Bazzani, A, Giovannozzi, Massimo, Scandale, Walter, Todesco, Ezio
Dynamic aperture estimates and phase space distortions in nonlinear betatronic motion (1995)
Todesco, Ezio, Giovannozzi, Massimo
Symplectic mappings which modelize the 4D betatronic motion in a magnetic lattice are considered. We define the dynamic aperture in terms of the connected volume in phase space of initial conditions...
Sorting strategies for the LHC based on normal forms (1995)
Scandale, Walter, Giovannozzi, Massimo, Grassi, R, Todesco, Ezio
A sorting approach to the magnetic random errors (1995)
Giovannozzi, Massimo, Grassi, R, Scandale, Walter, Todesco, Ezio