IPAC2022 - List of Authors (Humann, B.)

Paper	Title	Page
MOPOMS042	Comparison Between Run 2 TID Measurements and FLUKA Simulations in the CERN LHC Tunnel of the Atlas Insertion Region	732
	D. Prelipcean, K. Biłko, F. Cerutti, A. Ciccotelli, D. Di Francesca, R. García Alía, B. Humann, G. Lerner, D. Ricci, M. Sabaté-Gilarte CERN, Meyrin, Switzerland B. Humann TU Vienna, Wien, Austria
	In this paper we present a systematic benchmark between the simulated and the measured data for the radiation monitors useful for Radiation to Electronics (R2E) studies at the Large Hadron Collider (LHC) at CERN. For this purpose, the radiation levels in the main LHC tunnel on the right side of the Interaction Point 1 (ATLAS detector) are simulated using the FLUKA Monte Carlo code and compared against Total Ionising Dose (TID) measurements performed with the Beam Loss Monitoring (BLM) system, and 180 m of Distributed Optical Fibre Radiation Sensor (DOFRS). Considering the complexity and the scale of the simulations as well as the variety of the LHC operational parameters, we find a generally good agreement between measured and simulated radiation levels, typically within a factor of 2 or better.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS042
About •	Received ※ 08 June 2022 — Revised ※ 23 June 2022 — Accepted ※ 26 June 2022 — Issue date ※ 09 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST001	Radiation Load Studies for Superconducting Dipole Magnets in a 10 TeV Muon Collider	1671
	D. Calzolari, C. Carli, B. Humann, A. Lechner, G. Lerner, F. Salvat Pujol, D. Schulte, K. Skoufaris CERN, Meyrin, Switzerland B. Humann TU Vienna, Wien, Austria
	Among the various future lepton colliders under study, muon colliders offer the prospect of reaching the highest collision energies. Despite the promising potential of a multi-TeV muon collider, the short lifetime of muons poses a severe technological challenge for the collider design. In particular, the copious production of decay electrons and positrons along the collider ring requires the integration of continuous radiation absorbers inside superconducting magnets. The absorbers are needed to avoid quenches, reduce the heat dissipation in the cold mass and prevent magnet failures due to long-term radiation damage. In this paper, we present FLUKA shower simulations assessing the shielding requirements for high-field magnets of a 10 TeV muon collider. We quantify in particular the role of synchrotron photon emission by decay electrons and positrons, which helps in dispersing the energy carried by the decay products. For comparison, selected results for a 3 TeV muon collider are also presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST001
About •	Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST002	Synchrotron Radiation Impact on the FCC-ee Arcs	1675
	B. Humann TU Vienna, Wien, Austria F. Cerutti, B. Humann, R. Kersevan CERN, Meyrin, Switzerland
	Synchrotron radiation (SR) emitted by electron and positrons beams represents a major loss source in high energy circular colliders, such as the lepton version of the Future Circular Collider (FCC-ee) at CERN. In particular, for the operation mode at 182.5 GeV (above the top pair threshold), its spectrum makes it penetrate well beyond the vacuum chamber walls. In order to optimize its containment, dedicated absorbers are envisaged. In this contribution we report the energy deposition studies performed with FLUKA to assess heat load, time-integrated dose, power density and particle fluence distribution in the machine components and the surrounding environment. Different choices for the absorber material were considered and shielding options for electronics were investigated. Furthermore, possible positions for the booster ring were reviewed from the radiation exposure point of view.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST002
About •	Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 03 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST003	Implications of the Upgrade II of LHCb on the LHC Insertion Region 8: From Energy Deposition Studies to Mitigation Strategies	1679
	A. Ciccotelli The University of Manchester, Manchester, United Kingdom R.B. Appleby UMAN, Manchester, United Kingdom F. Butin, F. Cerutti, A. Ciccotelli, L.S. Esposito, B. Humann, M. Wehrle CERN, Meyrin, Switzerland B. Humann TU Vienna, Wien, Austria
	Starting from LHC Run3, a first upgrade of the LHCb experiment (Upgrade I) will enable oeration with a significantly increased instantaneous luminosity in the LHC Insertion Region 8 (IR8), up to 2·10³³/(cm² s). Moreover, the proposed second upgrade of the LHCb experiment (Upgrade II) aims at increasing it by an extra factor 7.5 and collecting an integrated luminosity of 400/fb by the end of Run6. Such an ambitious goal poses challenges not only for the detector but also for the accelerator components. Monte Carlo simulations represent a valuable tool to predict the implications of the radiation impact on the machine, especially for future operational scenarios. A detailed IR8 model implemented by means of the FLUKA code is presented in this study. With such a model, we calculated the power density and dose distributions in the superconducting coils of the LHC final focusing quadrupoles (Q1-Q3) and separation dipole (D1) and we highlight a few critical issues calling for mitigation measures. Our study addresses also the recombination dipole (D2) and the suitability of the present TANb absorber, as well as the proton losses in the Dispersion Suppressor (DS) and their implications.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST003
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT063	The FCCee Pre-Injector Complex	2007
	P. Craievich, B. Auchmann, S. Bettoni, H.-H. Braun, M. Duda, D. Hauenstein, E. Hohmann, R. Ischebeck, P.N. Juranič, J. Kosse, G.L. Orlandi, M. Pedrozzi, J.-Y. Raguin, S. Reiche, S.T. Sanfilippo, M. Schaer, N. Vallis, R. Zennaro PSI, Villigen PSI, Switzerland F. Alharthi, I. Chaikovska, S. Ogur Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France W. Bartmann, M. Benedikt, M.I. Besana, M. Calviani, S. Döbert, Y. Dutheil, O. Etisken, J.L. Grenard, A. Grudiev, B. Humann, A. Latina, A. Lechner, K. Oide, A. Perillo-Marcone, H.W. Pommerenke, R.L. Ramjiawan, Y. Zhao, F. Zimmermann CERN, Meyrin, Switzerland A. De Santis INFN/LNF, Frascati, Italy Y. Enomoto, K. Furukawa, K. Oide KEK, Ibaraki, Japan O. Etisken Kirikkale University, Kirikkale, Turkey C. Milardi LNF-INFN, Frascati, Italy T.O. Raubenheimer SLAC, Menlo Park, California, USA N. Vallis EPFL, Lausanne, Switzerland
	The international FCC study group published in 2019 a Conceptual Design Report for an electron-positron collider with a centre-of-mass energy from 90 to 365 GeV with a beam currents of up to 1.4 A per beam. The high beam current of this collider create challenging requirements on the injection chain and all aspects of the linac need to be carefully reconsidered and revisited, including the injection time structure. The entire beam dynamics studies for the full linac, damping ring and transfer lines are major activities of the injector complex design. A key point is that any increase of positron production and capture efficiency reduces the cost and complexity of the driver linac, the heat and radiation load of the converter system, and increases the operational margin. In this paper we will give an overview of the status of the injector complex design and introduce the new layout that has been proposed by the study group working in the context of the CHART collaboration. In this framework, furthermore, we also present the preliminary studies of the FCC-ee positron source highlighting the main requirements and constraints.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT063
About •	Received ※ 11 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 29 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK048	Radiation Load Studies for the FCC-ee Positron Source with a Superconducting Matching Device	2879
SUSPMF118	use link to see paper's listing under its alternate paper code
	B. Humann TU Vienna, Wien, Austria B. Auchmann, J. Kosse PSI, Villigen PSI, Switzerland I. Chaikovska, S. Ogur Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France B. Humann, A. Latina, A. Lechner, Y. Zhao CERN, Meyrin, Switzerland
	For an electron-positron collider like FCC-ee, the production of positrons plays a crucial role. One of the design options considered for the FCC-ee positron source employs a superconducting solenoid made of HTS coils as an adiabatic matching device. The solenoid, which is placed around the production target, is needed to capture positrons before they can be accelerated in a linear accelerator. A superconducting solenoid yields a higher peak field than a conventional-normal conducting magnetic flux concentrator, therefore increasing the achievable positron yield. In order to achieve an acceptable positron production, the considered target is made of tungsten-rhenium, which gives also a significant flux of un-wanted secondary particles, that in turn could generate a too large radiation load on the superconducting coils. In this study, we assess the feasibility of such a positron source by studying the heat load and long-term radiation damage in the superconducting matching device and surrounding structures. Results are presented for different geometric configurations of the superconducting matching device.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK048
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Comparison Between Run 2 TID Measurements and FLUKA Simulations in the CERN LHC Tunnel of the Atlas Insertion Region

732

D. Prelipcean, K. Biłko, F. Cerutti, A. Ciccotelli, D. Di Francesca, R. García Alía, B. Humann, G. Lerner, D. Ricci, M. Sabaté-Gilarte
CERN, Meyrin, Switzerland
B. Humann
TU Vienna, Wien, Austria

In this paper we present a systematic benchmark between the simulated and the measured data for the radiation monitors useful for Radiation to Electronics (R2E) studies at the Large Hadron Collider (LHC) at CERN. For this purpose, the radiation levels in the main LHC tunnel on the right side of the Interaction Point 1 (ATLAS detector) are simulated using the FLUKA Monte Carlo code and compared against Total Ionising Dose (TID) measurements performed with the Beam Loss Monitoring (BLM) system, and 180 m of Distributed Optical Fibre Radiation Sensor (DOFRS). Considering the complexity and the scale of the simulations as well as the variety of the LHC operational parameters, we find a generally good agreement between measured and simulated radiation levels, typically within a factor of 2 or better.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS042

About •

Received ※ 08 June 2022 — Revised ※ 23 June 2022 — Accepted ※ 26 June 2022 — Issue date ※ 09 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST001

Radiation Load Studies for Superconducting Dipole Magnets in a 10 TeV Muon Collider

1671

D. Calzolari, C. Carli, B. Humann, A. Lechner, G. Lerner, F. Salvat Pujol, D. Schulte, K. Skoufaris
CERN, Meyrin, Switzerland
B. Humann
TU Vienna, Wien, Austria

Among the various future lepton colliders under study, muon colliders offer the prospect of reaching the highest collision energies. Despite the promising potential of a multi-TeV muon collider, the short lifetime of muons poses a severe technological challenge for the collider design. In particular, the copious production of decay electrons and positrons along the collider ring requires the integration of continuous radiation absorbers inside superconducting magnets. The absorbers are needed to avoid quenches, reduce the heat dissipation in the cold mass and prevent magnet failures due to long-term radiation damage. In this paper, we present FLUKA shower simulations assessing the shielding requirements for high-field magnets of a 10 TeV muon collider. We quantify in particular the role of synchrotron photon emission by decay electrons and positrons, which helps in dispersing the energy carried by the decay products. For comparison, selected results for a 3 TeV muon collider are also presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST001

About •

Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST002

Synchrotron Radiation Impact on the FCC-ee Arcs

1675

B. Humann
TU Vienna, Wien, Austria
F. Cerutti, B. Humann, R. Kersevan
CERN, Meyrin, Switzerland

Synchrotron radiation (SR) emitted by electron and positrons beams represents a major loss source in high energy circular colliders, such as the lepton version of the Future Circular Collider (FCC-ee) at CERN. In particular, for the operation mode at 182.5 GeV (above the top pair threshold), its spectrum makes it penetrate well beyond the vacuum chamber walls. In order to optimize its containment, dedicated absorbers are envisaged. In this contribution we report the energy deposition studies performed with FLUKA to assess heat load, time-integrated dose, power density and particle fluence distribution in the machine components and the surrounding environment. Different choices for the absorber material were considered and shielding options for electronics were investigated. Furthermore, possible positions for the booster ring were reviewed from the radiation exposure point of view.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST002

About •

Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 03 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST003

Implications of the Upgrade II of LHCb on the LHC Insertion Region 8: From Energy Deposition Studies to Mitigation Strategies

1679

A. Ciccotelli
The University of Manchester, Manchester, United Kingdom
R.B. Appleby
UMAN, Manchester, United Kingdom
F. Butin, F. Cerutti, A. Ciccotelli, L.S. Esposito, B. Humann, M. Wehrle
CERN, Meyrin, Switzerland
B. Humann
TU Vienna, Wien, Austria

Starting from LHC Run3, a first upgrade of the LHCb experiment (Upgrade I) will enable oeration with a significantly increased instantaneous luminosity in the LHC Insertion Region 8 (IR8), up to 2·10³³/(cm² s). Moreover, the proposed second upgrade of the LHCb experiment (Upgrade II) aims at increasing it by an extra factor 7.5 and collecting an integrated luminosity of 400/fb by the end of Run6. Such an ambitious goal poses challenges not only for the detector but also for the accelerator components. Monte Carlo simulations represent a valuable tool to predict the implications of the radiation impact on the machine, especially for future operational scenarios. A detailed IR8 model implemented by means of the FLUKA code is presented in this study. With such a model, we calculated the power density and dose distributions in the superconducting coils of the LHC final focusing quadrupoles (Q1-Q3) and separation dipole (D1) and we highlight a few critical issues calling for mitigation measures. Our study addresses also the recombination dipole (D2) and the suitability of the present TANb absorber, as well as the proton losses in the Dispersion Suppressor (DS) and their implications.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST003

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT063

The FCCee Pre-Injector Complex

2007

P. Craievich, B. Auchmann, S. Bettoni, H.-H. Braun, M. Duda, D. Hauenstein, E. Hohmann, R. Ischebeck, P.N. Juranič, J. Kosse, G.L. Orlandi, M. Pedrozzi, J.-Y. Raguin, S. Reiche, S.T. Sanfilippo, M. Schaer, N. Vallis, R. Zennaro
PSI, Villigen PSI, Switzerland
F. Alharthi, I. Chaikovska, S. Ogur
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
W. Bartmann, M. Benedikt, M.I. Besana, M. Calviani, S. Döbert, Y. Dutheil, O. Etisken, J.L. Grenard, A. Grudiev, B. Humann, A. Latina, A. Lechner, K. Oide, A. Perillo-Marcone, H.W. Pommerenke, R.L. Ramjiawan, Y. Zhao, F. Zimmermann
CERN, Meyrin, Switzerland
A. De Santis
INFN/LNF, Frascati, Italy
Y. Enomoto, K. Furukawa, K. Oide
KEK, Ibaraki, Japan
O. Etisken
Kirikkale University, Kirikkale, Turkey
C. Milardi
LNF-INFN, Frascati, Italy
T.O. Raubenheimer
SLAC, Menlo Park, California, USA
N. Vallis
EPFL, Lausanne, Switzerland

The international FCC study group published in 2019 a Conceptual Design Report for an electron-positron collider with a centre-of-mass energy from 90 to 365 GeV with a beam currents of up to 1.4 A per beam. The high beam current of this collider create challenging requirements on the injection chain and all aspects of the linac need to be carefully reconsidered and revisited, including the injection time structure. The entire beam dynamics studies for the full linac, damping ring and transfer lines are major activities of the injector complex design. A key point is that any increase of positron production and capture efficiency reduces the cost and complexity of the driver linac, the heat and radiation load of the converter system, and increases the operational margin. In this paper we will give an overview of the status of the injector complex design and introduce the new layout that has been proposed by the study group working in the context of the CHART collaboration. In this framework, furthermore, we also present the preliminary studies of the FCC-ee positron source highlighting the main requirements and constraints.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT063

About •

Received ※ 11 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 29 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK048

Radiation Load Studies for the FCC-ee Positron Source with a Superconducting Matching Device

2879

SUSPMF118

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

B. Humann
TU Vienna, Wien, Austria
B. Auchmann, J. Kosse
PSI, Villigen PSI, Switzerland
I. Chaikovska, S. Ogur
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
B. Humann, A. Latina, A. Lechner, Y. Zhao
CERN, Meyrin, Switzerland

For an electron-positron collider like FCC-ee, the production of positrons plays a crucial role. One of the design options considered for the FCC-ee positron source employs a superconducting solenoid made of HTS coils as an adiabatic matching device. The solenoid, which is placed around the production target, is needed to capture positrons before they can be accelerated in a linear accelerator. A superconducting solenoid yields a higher peak field than a conventional-normal conducting magnetic flux concentrator, therefore increasing the achievable positron yield. In order to achieve an acceptable positron production, the considered target is made of tungsten-rhenium, which gives also a significant flux of un-wanted secondary particles, that in turn could generate a too large radiation load on the superconducting coils. In this study, we assess the feasibility of such a positron source by studying the heat load and long-term radiation damage in the superconducting matching device and surrounding structures. Results are presented for different geometric configurations of the superconducting matching device.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK048

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 07 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)