IPAC2016 - List of Authors (Salvachua, B.)

Paper	Title	Page
TUPMW002	LHC Luminosity Modeling for RUNII	1403
	F. Antoniou, G. Arduini, M. Hostettler, M. Lamont, S. Papadopoulou, Y. Papaphilippou, G. Papotti, M. Pojer, B. Salvachua, M. Wyszynski CERN, Geneva, Switzerland
	Funding: Research supported by the High Luminosity LHC project After a long shut-down (LS1), LHC restarted its operation on April 2015 at a record energy of 6.5TeV, achieving soon a good luminosity performance. In this paper, a luminosity model based on the three main components of the LHC luminosity degradation (intrabeam scattering, synchrotron radiation and luminosity burn-off), is compared with data from runII. Based on the observations, other sources of luminosity degradation are discussed and the model is refined. Finally, based on the experience from runI and runII, the model is used for integrated luminosity projections for the HL-LHC beam parameters.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW002
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TUPMW007	Impact of Long Range Beam-Beam Effects on Intensity and Luminosity Lifetimes from the 2015 LHC Run	1422
	M.P. Crouch, R.B. Appleby UMAN, Manchester, United Kingdom D. Banfi, C. Tambasco EPFL, Lausanne, Switzerland J. Barranco, R. Bruce, X. Buffat, T. Pieloni, M. Pojer, B. Salvachua, G. Trad CERN, Geneva, Switzerland B.D. Muratori STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: Research supported by the High Luminosity LHC project Luminosity is one of the key parameters that determines the performance of colliding beams in the Large Hadron Collider (LHC). Luminosity can therefore be used to quantify the impact of beam-beam interactions on the beam lifetimes and emittances. The High Luminosity Large Hadron Collider (HL-LHC) project aims to reach higher luminosities, approximately a factor of 7 larger than the nominal LHC at peak luminosity without crab cavities. Higher luminosities are achieved by increasing the bunch populations and reducing the transverse beam sizes. This results in stronger beam-beam effects. Here the LHC luminosity and beam intensity decay rates are analysed as a function of reducing beam separation with the aim of characterising the impact of beam-beam effects on the luminosity and beam lifetime. The analysis and results are discussed with possible application to the HL-LHC upgrade.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW007
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TUPMW013	Experimental Demonstration of β* Leveling at the LHC	1442
SUPSS001	use link to see paper's listing under its alternate paper code
	A.A. Gorzawski, D. Mirarchi, B. Salvachua, J. Wenninger CERN, Geneva, Switzerland
	The HL-LHC project foresees to boost the LHC peak luminosity beyond the capabilities of the LHC experimental detectors. Leveling the luminosity down to a constant value that is sustainable for the experiments is therefore the operational baseline of HL-LHC. Various luminosity leveling techniques are available at the LHC. Leveling by adjusting β^, the betatron function at the interaction point, to maintain a constant luminosity is favorable because the beams remain head-on which provides optimal stability from the point of view of collective effects. Smooth leveling by β^ requires however excellent control of the beam orbits and beam losses in the interaction regions since the beam offsets should not vary by more than around one r.m.s. beam size during the process. This leveling scheme has been successfully tested and experimentally demonstrated during the LHC machine development program in 2015. This paper presents results on luminosity leveling over a β^* range from 10 m to 0.8 m and provides an outlook on future developments and use of this technique at the LHC.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW013
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TUPMW014	Improved Aperture Measurements at the LHC and Results from their Application in 2015	1446
	P.D. Hermes, R. Bruce, M. Fiascaris, H. Garcia, M. Giovannozzi, A. Mereghetti, D. Mirarchi, E. Quaranta, S. Redaelli, B. Salvachua, G. Valentino CERN, Geneva, Switzerland R. Kwee-Hinzmann Royal Holloway, University of London, Surrey, United Kingdom E. Quaranta Politecnico/Milano, Milano, Italy
	A good knowledge of the available aperture in the LHC is essential for a safe operation due to the risk of magnet quenches or even damage in case of uncontrolled beam losses. Experimental validations of the available aperture are therefore crucial and were in the past carried out by either a collimator scan combined with beam excitations or through the use of local orbit bumps. In this paper, we show a first comparison of these methods in the same machine configuration, as well as a new very fast method based on a beam-based collimator alignment and a new faster variant of the collimator scan method. The methods are applied to the LHC operational configuration for 2015 at injection and with squeezed beams and the measured apertures are presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW014
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TUPMW021	Roman Pot Insertions in High-Intensity Beams for the CT-PPS Project at LHC	1473
	M. Deile, R. Bruce, A. Mereghetti, D. Mirarchi, S. Redaelli, B. Salvachua, B. Salvant, G. Valentino CERN, Geneva, Switzerland
	The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) at the LHC IP5 aims at exploring diffractive physics at high luminosity in standard LHC fills. It is based on 14 Roman Pots (RPs), designed to host tracking and time-of-flight detectors for measuring the kinematics of leading protons. To reach the physics goals, the RPs will finally have to approach the beams to distances of 15 beam σs (i.e. ~1.5 mm) or closer. After problems with showers and impedance heating in first high-luminosity RP insertions in 2012, the LS1 of LHC was used for upgrades in view of impedance minimisation and for adding new collimators to intercept RP-induced showers. In 2015 the effectiveness of these improvements was shown by successfully inserting the RPs in all LHC beam intensity steps to a first-phase distance of ~25 σs. This contribution reviews the measurements of debris showers and impedance effects, i.e. the data from Beam Loss Monitors, beam vacuum gauges and temperature sensors. The dependences of the observables on the luminosity are shown. Extrapolations to L=10³⁴ cm^-2 s^-1 and smaller distances to the beam do not indicate any fundamental problems. The plans for 2016 are outlined.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW021
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WEOCA01	Operation of the LHC with Protons at High Luminosity and High Energy	2066
	G. Papotti, M. Albert, R. Alemany-Fernandez, G.E. Crockford, K. Fuchsberger, R. Giachino, M. Giovannozzi, G.H. Hemelsoet, W. Höfle, D. Jacquet, M. Lamont, D. Nisbet, L. Normann, M. Pojer, L. Ponce, S. Redaelli, B. Salvachua, M. Solfaroli Camillocci, R. Suykerbuyk, J.A. Uythoven, J. Wenninger CERN, Geneva, Switzerland
	In 2015 the Large Hadron Collider (LHC) entered the first year in its second long Run, after a 2-year shutdown that prepared it for high energy. The first two months of beam operation were dedicated to setting up the nominal cycle for proton-proton operation at 6.5 TeV/beam, and culminated with the first physics with 3 nominal bunches/ring at 13 TeV CoM on 3 June. The year continued with a stepwise intensity ramp up that allowed reaching 2244 bunches/ring for a peak luminosity of ~5·10³³ cm^-2s⁻¹ and a total of just above 4 fb-1 delivered to the high luminosity experiments. Beam operation was shaped by the high intensity effects, e.g. electron cloud and macroparticle-induced fast losses (UFOs), which on a few occasions caused the first beam induced quenches at high energy. This paper describes the operational experience with high intensity and high energy at the LHC, together with the issues that had to be tackled along the way.
	Slides WEOCA01 [4.013 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEOCA01
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WEPMW007	Validation of Off-momentum Cleaning Performance of the LHC Collimation System	2427
	B. Salvachua, P. Baudrenghien, R. Bruce, H. Garcia, P.D. Hermes, S. Jackson, M. Jaussi, A. Mereghetti, D. Mirarchi, S. Redaelli, H. Timko, G. Valentino, A. Valloni CERN, Geneva, Switzerland R. Kwee-Hinzmann Royal Holloway, University of London, Surrey, United Kingdom
	The LHC collimation system is designed to provide effective cleaning against losses coming from off-momentum particles, either due to un-captured beam or to an unexpected RF frequency change. For this reason the LHC is equipped with a hierarchy of collimators in IR3: primary, secondary and absorber collimators. After every collimator alignment or change of machine configuration the off-momentum cleaning efficiency is validated with loss maps at low intensity. We describe here the improved technique used in 2015 to generate such loss maps without completely dumping the beam into the collimators. The achieved performance of the collimation system for momentum cleaning is reviewed.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW007
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WEPMW028	First Attempts at using Active Halo Control at the LHC	2486
	J.F. Wagner Goethe Universität Frankfurt, Frankfurt am Main, Germany R. Bruce, H. Garcia Morales, W. Höfle, G. Kotzian, R. Kwee-Hinzmann, A. Langner, A. Mereghetti, E. Quaranta, S. Redaelli, A. Rossi, B. Salvachua, R. Tomás, G. Valentino, D. Valuch, J.F. Wagner CERN, Geneva, Switzerland G. Stancari Fermilab, Batavia, Illinois, USA
	Funding: Research supported by the High Luminosity LHC project. The beam halo population is a non-negligible factor for the performance of the LHC collimation system and the machine protection. In particular this could become crucial for aiming at stored beam energies of 700 MJ in the High Luminosity (HL-LHC) project, in order to avoid beam dumps caused by orbit jitter and to ensure safety during a crab cavity failure. Therefore several techniques to safely deplete the halo, i.e. active halo control, are under development. In a first attempt a novel way for safe halo depletion was tested with particle narrow-band excitation employing the LHC Transverse Damper (ADT). At an energy of 450 GeV a bunch selective beam tail scraping without affecting the core distribution was attempted. This paper presents the first measurement results, as well as a simple simulation to model the underlying dynamics.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW028
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WEPMW029	Simulation of Heavy-Ion Beam Losses with the SixTrack-FLUKA Active Coupling	2490
SUPSS008	use link to see paper's listing under its alternate paper code
	P.D. Hermes, R. Bruce, F. Cerutti, A. Ferrari, J.M. Jowett, A. Lechner, A. Mereghetti, D. Mirarchi, P.G. Ortega, S. Redaelli, B. Salvachua, E. Skordis, G. Valentino, V. Vlachoudis CERN, Geneva, Switzerland
	Funding: Work suppported by the Wolfgang Gentner Programme of the German BMBF The LHC heavy-ion program aims to further increase the stored ion beam energy, putting high demands on the LHC collimation system. Accurate simulations of the ion collimation efficiency are crucial to validate the feasibility of new proposed configurations and beam parameters. In this paper we present a generalized framework of the SixTrack-FLUKA coupling to simulate the fragmentation of heavy-ions in the collimators and their motion in the LHC lattice. We compare heavy-ion loss maps simulated on the basis of this framework with the loss distributions measured during heavy-ion operation in 2011 and 2015.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW029
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WEPOY030	First BTF Measurements at the Large Hadron Collider	3051
SUPSS061	use link to see paper's listing under its alternate paper code
	C. Tambasco, A. Boccardi, X. Buffat, K. Fuchsberger, M. Gąsior, R. Giachino, T. Lefèvre, T.E. Levens, T. Pieloni, M. Pojer, B. Salvachua, M. Solfaroli Camillocci CERN, Geneva, Switzerland J. Barranco, C. Tambasco EPFL, Lausanne, Switzerland
	During the Run I in 2012, several instabilities have been observed at the Large Hadron Collider (LHC) during the Betatron squeeze. The predictions of instability thresholds are based on the computation of the beam Landau damping by calculating the Stability Diagrams (SD). These instabilities could be explained by a deterioration of the SD due to beam-beam resonance excitation which could change the particle distributions. Beam Transfer Functions (BTF) provide a measurement of the Stability Diagram. The BTFs are sensitive to the particle detuning with amplitude as well as to the particle distributions therefore they represent a powerful tool to understand experimentally the stability of beams during the LHC operational cycle. First BTF measurements at the LHC are presented for different machine configurations and settings and compared to predictions.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOY030
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Paper

Title

Page

LHC Luminosity Modeling for RUNII

1403

F. Antoniou, G. Arduini, M. Hostettler, M. Lamont, S. Papadopoulou, Y. Papaphilippou, G. Papotti, M. Pojer, B. Salvachua, M. Wyszynski
CERN, Geneva, Switzerland

Funding: Research supported by the High Luminosity LHC project
After a long shut-down (LS1), LHC restarted its operation on April 2015 at a record energy of 6.5TeV, achieving soon a good luminosity performance. In this paper, a luminosity model based on the three main components of the LHC luminosity degradation (intrabeam scattering, synchrotron radiation and luminosity burn-off), is compared with data from runII. Based on the observations, other sources of luminosity degradation are discussed and the model is refined. Finally, based on the experience from runI and runII, the model is used for integrated luminosity projections for the HL-LHC beam parameters.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW002

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TUPMW007

Impact of Long Range Beam-Beam Effects on Intensity and Luminosity Lifetimes from the 2015 LHC Run

1422

M.P. Crouch, R.B. Appleby
UMAN, Manchester, United Kingdom
D. Banfi, C. Tambasco
EPFL, Lausanne, Switzerland
J. Barranco, R. Bruce, X. Buffat, T. Pieloni, M. Pojer, B. Salvachua, G. Trad
CERN, Geneva, Switzerland
B.D. Muratori
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Funding: Research supported by the High Luminosity LHC project
Luminosity is one of the key parameters that determines the performance of colliding beams in the Large Hadron Collider (LHC). Luminosity can therefore be used to quantify the impact of beam-beam interactions on the beam lifetimes and emittances. The High Luminosity Large Hadron Collider (HL-LHC) project aims to reach higher luminosities, approximately a factor of 7 larger than the nominal LHC at peak luminosity without crab cavities. Higher luminosities are achieved by increasing the bunch populations and reducing the transverse beam sizes. This results in stronger beam-beam effects. Here the LHC luminosity and beam intensity decay rates are analysed as a function of reducing beam separation with the aim of characterising the impact of beam-beam effects on the luminosity and beam lifetime. The analysis and results are discussed with possible application to the HL-LHC upgrade.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW007

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TUPMW013

Experimental Demonstration of β* Leveling at the LHC

1442

SUPSS001

use link to see paper's listing under its alternate paper code

A.A. Gorzawski, D. Mirarchi, B. Salvachua, J. Wenninger
CERN, Geneva, Switzerland

The HL-LHC project foresees to boost the LHC peak luminosity beyond the capabilities of the LHC experimental detectors. Leveling the luminosity down to a constant value that is sustainable for the experiments is therefore the operational baseline of HL-LHC. Various luminosity leveling techniques are available at the LHC. Leveling by adjusting β^*, the betatron function at the interaction point, to maintain a constant luminosity is favorable because the beams remain head-on which provides optimal stability from the point of view of collective effects. Smooth leveling by β^* requires however excellent control of the beam orbits and beam losses in the interaction regions since the beam offsets should not vary by more than around one r.m.s. beam size during the process. This leveling scheme has been successfully tested and experimentally demonstrated during the LHC machine development program in 2015. This paper presents results on luminosity leveling over a β^* range from 10 m to 0.8 m and provides an outlook on future developments and use of this technique at the LHC.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW013

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TUPMW014

Improved Aperture Measurements at the LHC and Results from their Application in 2015

1446

P.D. Hermes, R. Bruce, M. Fiascaris, H. Garcia, M. Giovannozzi, A. Mereghetti, D. Mirarchi, E. Quaranta, S. Redaelli, B. Salvachua, G. Valentino
CERN, Geneva, Switzerland
R. Kwee-Hinzmann
Royal Holloway, University of London, Surrey, United Kingdom
E. Quaranta
Politecnico/Milano, Milano, Italy

A good knowledge of the available aperture in the LHC is essential for a safe operation due to the risk of magnet quenches or even damage in case of uncontrolled beam losses. Experimental validations of the available aperture are therefore crucial and were in the past carried out by either a collimator scan combined with beam excitations or through the use of local orbit bumps. In this paper, we show a first comparison of these methods in the same machine configuration, as well as a new very fast method based on a beam-based collimator alignment and a new faster variant of the collimator scan method. The methods are applied to the LHC operational configuration for 2015 at injection and with squeezed beams and the measured apertures are presented.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW014

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TUPMW021

Roman Pot Insertions in High-Intensity Beams for the CT-PPS Project at LHC

1473

M. Deile, R. Bruce, A. Mereghetti, D. Mirarchi, S. Redaelli, B. Salvachua, B. Salvant, G. Valentino
CERN, Geneva, Switzerland

The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) at the LHC IP5 aims at exploring diffractive physics at high luminosity in standard LHC fills. It is based on 14 Roman Pots (RPs), designed to host tracking and time-of-flight detectors for measuring the kinematics of leading protons. To reach the physics goals, the RPs will finally have to approach the beams to distances of 15 beam σs (i.e. ~1.5 mm) or closer. After problems with showers and impedance heating in first high-luminosity RP insertions in 2012, the LS1 of LHC was used for upgrades in view of impedance minimisation and for adding new collimators to intercept RP-induced showers. In 2015 the effectiveness of these improvements was shown by successfully inserting the RPs in all LHC beam intensity steps to a first-phase distance of ~25 σs. This contribution reviews the measurements of debris showers and impedance effects, i.e. the data from Beam Loss Monitors, beam vacuum gauges and temperature sensors. The dependences of the observables on the luminosity are shown. Extrapolations to L=10³⁴ cm^-2 s^-1 and smaller distances to the beam do not indicate any fundamental problems. The plans for 2016 are outlined.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMW021

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WEOCA01

Operation of the LHC with Protons at High Luminosity and High Energy

2066

G. Papotti, M. Albert, R. Alemany-Fernandez, G.E. Crockford, K. Fuchsberger, R. Giachino, M. Giovannozzi, G.H. Hemelsoet, W. Höfle, D. Jacquet, M. Lamont, D. Nisbet, L. Normann, M. Pojer, L. Ponce, S. Redaelli, B. Salvachua, M. Solfaroli Camillocci, R. Suykerbuyk, J.A. Uythoven, J. Wenninger
CERN, Geneva, Switzerland

In 2015 the Large Hadron Collider (LHC) entered the first year in its second long Run, after a 2-year shutdown that prepared it for high energy. The first two months of beam operation were dedicated to setting up the nominal cycle for proton-proton operation at 6.5 TeV/beam, and culminated with the first physics with 3 nominal bunches/ring at 13 TeV CoM on 3 June. The year continued with a stepwise intensity ramp up that allowed reaching 2244 bunches/ring for a peak luminosity of ~5·10³³ cm^-2s⁻¹ and a total of just above 4 fb-1 delivered to the high luminosity experiments. Beam operation was shaped by the high intensity effects, e.g. electron cloud and macroparticle-induced fast losses (UFOs), which on a few occasions caused the first beam induced quenches at high energy. This paper describes the operational experience with high intensity and high energy at the LHC, together with the issues that had to be tackled along the way.

Slides WEOCA01 [4.013 MB]

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEOCA01

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WEPMW007

Validation of Off-momentum Cleaning Performance of the LHC Collimation System

2427

B. Salvachua, P. Baudrenghien, R. Bruce, H. Garcia, P.D. Hermes, S. Jackson, M. Jaussi, A. Mereghetti, D. Mirarchi, S. Redaelli, H. Timko, G. Valentino, A. Valloni
CERN, Geneva, Switzerland
R. Kwee-Hinzmann
Royal Holloway, University of London, Surrey, United Kingdom

The LHC collimation system is designed to provide effective cleaning against losses coming from off-momentum particles, either due to un-captured beam or to an unexpected RF frequency change. For this reason the LHC is equipped with a hierarchy of collimators in IR3: primary, secondary and absorber collimators. After every collimator alignment or change of machine configuration the off-momentum cleaning efficiency is validated with loss maps at low intensity. We describe here the improved technique used in 2015 to generate such loss maps without completely dumping the beam into the collimators. The achieved performance of the collimation system for momentum cleaning is reviewed.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW007

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WEPMW028

First Attempts at using Active Halo Control at the LHC

2486

J.F. Wagner
Goethe Universität Frankfurt, Frankfurt am Main, Germany
R. Bruce, H. Garcia Morales, W. Höfle, G. Kotzian, R. Kwee-Hinzmann, A. Langner, A. Mereghetti, E. Quaranta, S. Redaelli, A. Rossi, B. Salvachua, R. Tomás, G. Valentino, D. Valuch, J.F. Wagner
CERN, Geneva, Switzerland
G. Stancari
Fermilab, Batavia, Illinois, USA

Funding: Research supported by the High Luminosity LHC project.
The beam halo population is a non-negligible factor for the performance of the LHC collimation system and the machine protection. In particular this could become crucial for aiming at stored beam energies of 700 MJ in the High Luminosity (HL-LHC) project, in order to avoid beam dumps caused by orbit jitter and to ensure safety during a crab cavity failure. Therefore several techniques to safely deplete the halo, i.e. active halo control, are under development. In a first attempt a novel way for safe halo depletion was tested with particle narrow-band excitation employing the LHC Transverse Damper (ADT). At an energy of 450 GeV a bunch selective beam tail scraping without affecting the core distribution was attempted. This paper presents the first measurement results, as well as a simple simulation to model the underlying dynamics.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW028

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WEPMW029

Simulation of Heavy-Ion Beam Losses with the SixTrack-FLUKA Active Coupling

2490

SUPSS008

use link to see paper's listing under its alternate paper code

P.D. Hermes, R. Bruce, F. Cerutti, A. Ferrari, J.M. Jowett, A. Lechner, A. Mereghetti, D. Mirarchi, P.G. Ortega, S. Redaelli, B. Salvachua, E. Skordis, G. Valentino, V. Vlachoudis
CERN, Geneva, Switzerland

Funding: Work suppported by the Wolfgang Gentner Programme of the German BMBF
The LHC heavy-ion program aims to further increase the stored ion beam energy, putting high demands on the LHC collimation system. Accurate simulations of the ion collimation efficiency are crucial to validate the feasibility of new proposed configurations and beam parameters. In this paper we present a generalized framework of the SixTrack-FLUKA coupling to simulate the fragmentation of heavy-ions in the collimators and their motion in the LHC lattice. We compare heavy-ion loss maps simulated on the basis of this framework with the loss distributions measured during heavy-ion operation in 2011 and 2015.

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reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMW029

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WEPOY030

First BTF Measurements at the Large Hadron Collider

3051

SUPSS061

use link to see paper's listing under its alternate paper code

C. Tambasco, A. Boccardi, X. Buffat, K. Fuchsberger, M. Gąsior, R. Giachino, T. Lefèvre, T.E. Levens, T. Pieloni, M. Pojer, B. Salvachua, M. Solfaroli Camillocci
CERN, Geneva, Switzerland
J. Barranco, C. Tambasco
EPFL, Lausanne, Switzerland

During the Run I in 2012, several instabilities have been observed at the Large Hadron Collider (LHC) during the Betatron squeeze. The predictions of instability thresholds are based on the computation of the beam Landau damping by calculating the Stability Diagrams (SD). These instabilities could be explained by a deterioration of the SD due to beam-beam resonance excitation which could change the particle distributions. Beam Transfer Functions (BTF) provide a measurement of the Stability Diagram. The BTFs are sensitive to the particle detuning with amplitude as well as to the particle distributions therefore they represent a powerful tool to understand experimentally the stability of beams during the LHC operational cycle. First BTF measurements at the LHC are presented for different machine configurations and settings and compared to predictions.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOY030

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