IPAC2012 - List of Keywords (interaction-region)

Paper	Title	Other Keywords	Page
MOPPC044	Gallium as a Possible Target Material for a Muon Collider or Neutrino Factory	target, proton, factory, collider	232
	X.P. Ding UCLA, Los Angeles, California, USA J.S. Berg, H.G. Kirk, H. K. Sayed BNL, Upton, Long Island, New York, USA V.B. Graves ORNL, Oak Ridge, Tennessee, USA K.T. McDonald PU, Princeton, New Jersey, USA N. Souchlas, R.J. Weggel Particle Beam Lasers, Inc., Northridge, California, USA
	Funding: Work support by the U.S. Department of Energy in part under Awards No. DE-AC02-98CH10886 (BNL) and No. DF-FG02-92ER40695 (UCLA) We consider the potential for a free-gallium-jet as an option for the pion-production target at a Muon Collider or Neutrino Factory. Advantages of such a target choice are its liquid state at relatively low temperature, its relatively efficient meson production, and its lower activation (compared to mercury). Using the MARS15 code, we have simulated particle production initiated by incoming protons with kinetic energies (KE) between 2 and 16~GeV. For each proton beam energy, we optimized the geometric parameters of the target: the radius of the liquid jet, the incoming proton beam angle, and the crossing angle between the jet and the proton beam. We compare the quantity of generated muons using a Ga target to that from a mercury jet target.

MOPPR076	Using the BRAN Luminosity Detectors for Beam Emittance Monitoring During LHC Physics Runs	luminosity, emittance, monitoring, proton	966
	A. Ratti, H.S. Matis, M. Placidi, W.C. Turner LBNL, Berkeley, California, USA E. Bravin CERN, Geneva, Switzerland T.E. Lahey SLAC, Menlo Park, California, USA E.S.M. McCrory Fermilab, Batavia, USA R. Miyamoto ESS, Lund, Sweden S.M. White BNL, Upton, Long Island, New York, USA
	Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP). The BRAN Ionization Chambers installed at the IP1 and IP5 Interaction Points of the LHC provide a relative measurement of the total and bunch-by-bunch luminosities. This information, combined with the logged bunch charges from a fast BCT monitor, offers the possibility of evaluating the Interaction Area in collision for each of the colliding bunch pairs and monitor its time evolution. A Graphic User Interface (GUI) has been implemented to display the interaction area of the proton bunches interacting in IP1 and IP5 during each of the Physics Runs in the attempt of displaying the contribution to the Luminosity time decay originating from possible emittance blow-up when operating the Accelerator close to the beam-beam limit. Early results confirm the ability to characterize the bunch by bunch emittance behavior during the store and study possible differences among bunches in the same fill.

TUOAB02	Investigation of the Use of Silicon, Diamond and Liquid Helium Detectors for Beam Loss Measurements at 2 Kelvin	cryogenics, radiation, proton, electron	1080
	C. Kurfuerst, B. Dehning, W.T. Eisel, M. Sapinski CERN, Geneva, Switzerland V. Eremin IOFFE, St. Petersburg, Russia C. Fabjan HEPHY, Wien, Austria
	At the triplet magnets, close to the interaction regions of the LHC, the current Beam Loss Monitoring (BLM) system is very sensitive to the debris from the collisions. For future beams with higher energy and higher luminosity this will lead to a situation in which the BLM system can no longer distinguish between these interaction products and quench-provoking beam losses from the primary proton beams. The solution investigated is to locate the detectors as close as possible to the superconducting coil, i.e. the element to be protected. This means putting detectors inside the cold mass of the superconducting magnets at 1.9 K. As possible candidates for such loss monitors, diamond, silicon and a liquid helium chamber have been tested in a proton beam at liquid helium temperatures. The initial promising results from these tests will be presented and discussed in this contribution.
	Slides TUOAB02 [3.412 MB]

TUOBC02	Small-Beta Collimation at SuperKEKB to Stop Beam-Gas Scattered Particles and to Avoid Transverse Mode Coupling Instability	impedance, scattering, coupling, simulation	1104
	H. Nakayama, Y. Funakoshi, K. Kanazawa, K. Ohmi, Y. Ohnishi, Y. Suetsugu KEK, Tsukuba, Japan H. Nakano Tohoku University, Graduate School of Science, Sendai, Japan
	At SuperKEKB, beam particles which are Coulomb-scattered by the residual gas molecular change direction and will be eventually lost by hitting beam pipe inner wall. Due to large vertical beta function and small beam pipe radius just before IP, most of Coulomb-scattered particles are lost there and are very dangerous for the Belle-II detector. To stop such particles before the IP, vertical collimators are installed in the ring. However, such vertical collimators should be placed very close (few mm) to the beam and therefore induce transverse mode coupling instability. To avoid beam instability and achieve collimation at the same time, we need to install vertical collimators where vertical beta function is SMALL, since maximum collimator width determined by aperture condition is proportional to β^1/2, and minimum collimator width determined by instability is proportional to β^2/3. We present our strategy to stop beam-gas scattered particles and simulated loss rate in the interaction region. We will also show dedicated vertical collimator design to achieve less instability.
	Slides TUOBC02 [2.196 MB]

WEPPD031	A Transverse Electron Target for Heavy Ion Storage Rings	electron, target, ion, simulation	2573
	S. Geyer, O. Meusel IAP, Frankfurt am Main, Germany O.K. Kester GSI, Darmstadt, Germany
	Funding: supported by HIC for FAIR A transverse electron target is a well suited concept for storage rings to investigate electron-ion interactions processes relevant for heavy ion accelerators. In comparison with an internal gas target, it promises a better energy resolution but still has the advantage, in contrast to an electron cooler, of access to the interaction region for photon and electron spectroscopy under large solid angles. The new electron target is suited for the use under the UHV requirements of a storage ring and realizes an open geometry for spectroscopy. A simple design based on electrostatic fields was chosen. The sheet beam application provides a higher perveance limit and a smaller potential depression than a cylindrical gun arrangement. The adjustable electron energy ranges between several 10eV and a few keV. The setup will be installed applying the so-called animated beam technique. The electron target is dedicated to the NESR at the new FAIR facility. First measurements are planned at a test bench and subsequent tests at the Frankfurt Low Energy Storage Ring (FLSR) are envisaged. An overview of the progress in the development of the transverse electron target will be given.

WEPPD037	Shielding of Superconducting Coils for a 4-MW Muon-Collider Target System	shielding, target, collider, factory	2591
	R.J. Weggel, N. Souchlas Particle Beam Lasers, Inc., Northridge, California, USA X.P. Ding UCLA, Los Angeles, California, USA V.B. Graves ORNL, Oak Ridge, Tennessee, USA H.G. Kirk, H. K. Sayed BNL, Upton, Long Island, New York, USA K.T. McDonald PU, Princeton, New Jersey, USA
	Funding: Work support by the U.S. Department of Energy in part under Award No. DE-AC02-98CH10886 The target system envisioned for a Muon Collider/Neutrino Factory features a liquid Hg jet target immersed in a 20-T solenoidal field. Field quality limits intercoil gaps to ~ 40% of the O.D. of the flanking coils. Longitudinal sag of the tungsten shielding vessels limits their length to ~ 7 m. Support members adequate to resist intercryostat axial forces require an aggregate cross section of ~ 0.1 m²; the cryogenic heat leakage may be large. The innermost shielding vessel wall can be adequately cooled by helium gas only if its pressure is ~ 10 atm and its velocity is ~ 200m/s. However, the analysis in this paper found none of these engineering challenges to be insurmountable.

THPPC065	Phase and Frequency Locked Magnetron	cavity, shielding, controls, cathode	3440
	M.L. Neubauer, A. Dudas, R. Sah Muons, Inc, Batavia, USA A. Moretti, M. Popovic Fermilab, Batavia, USA
	Funding: Supported in part by SBIR Grant 4724 · 09SC02766 Phase and Frequency locked magnetrons have many important uses from phased array ground penetrating radars to SRF sources. We report on the recent progress in making such a magnetron. The ferrite/garnet material has passed bakeout and outgassing tests with outgassing rates well below the requirements. The magnetic field requirements for adjusting the frequency by changing the microwave properties of the ferrite/garnet have been determined. The design of the anode structure with ferrites, magnetic shielding, and magnetic bias has been completed for a low power test. We report on the design status. Muons, Inc. has negotiated an contract with a manufacturing firm, L-3 Electron Devices California Tube Laboratory, Inc., to be the Manufacturing Partner for the commercialization of this technology and support these Phase II efforts.

THPPD023	Solenoid Field Calculation of the SuperKEKB Interaction Region	solenoid, quadrupole, superconducting-magnet, optics	3548
	N. Ohuchi, Y. Arimoto, M. Iwasaki, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, M. Tawada, K. Tsuchiya, H. Yamaoka KEK, Ibaraki, Japan
	The SuperKEKB is the electron-positron collider, and the target luminosity is 8×10³⁵ cm^-2s⁻¹, which is 40 times larger than the attained luminosity of KEKB. The beam final focus system consists of many types of superconducting magnets as 8 quadrupoles, 40 correctors and 4 compensation solenoids. These focusing magnets and correctors are designed to be operated inside the particle detector, Belle, and under the solenoid field of 1.5 T. From the analysis of beam optics, the solenoid field profile has serious impact on the beam vertical emittance. We designs the solenoid field profile along the Belle axis in a 2-dimensional model as the first step, and now we developed this model to the 3-dimensional calculation in detail. The solenoid field profiles along the both beam lines are generated with the combine solenoid field by the Belle solenoid and the compensation solenoids, and the magnetic components of the magnets and the magnetic shields on the beam lines. The model is very complicate. From the calculation results, we will discuss the influence on the beam optics and the final focusing magnet system.

Paper

Title

Other Keywords

Page

MOPPC044

Gallium as a Possible Target Material for a Muon Collider or Neutrino Factory

target, proton, factory, collider

232

X.P. Ding
UCLA, Los Angeles, California, USA
J.S. Berg, H.G. Kirk, H. K. Sayed
BNL, Upton, Long Island, New York, USA
V.B. Graves
ORNL, Oak Ridge, Tennessee, USA
K.T. McDonald
PU, Princeton, New Jersey, USA
N. Souchlas, R.J. Weggel
Particle Beam Lasers, Inc., Northridge, California, USA

Funding: Work support by the U.S. Department of Energy in part under Awards No. DE-AC02-98CH10886 (BNL) and No. DF-FG02-92ER40695 (UCLA)
We consider the potential for a free-gallium-jet as an option for the pion-production target at a Muon Collider or Neutrino Factory. Advantages of such a target choice are its liquid state at relatively low temperature, its relatively efficient meson production, and its lower activation (compared to mercury). Using the MARS15 code, we have simulated particle production initiated by incoming protons with kinetic energies (KE) between 2 and 16~GeV. For each proton beam energy, we optimized the geometric parameters of the target: the radius of the liquid jet, the incoming proton beam angle, and the crossing angle between the jet and the proton beam. We compare the quantity of generated muons using a Ga target to that from a mercury jet target.

MOPPR076

Using the BRAN Luminosity Detectors for Beam Emittance Monitoring During LHC Physics Runs

luminosity, emittance, monitoring, proton

966

A. Ratti, H.S. Matis, M. Placidi, W.C. Turner
LBNL, Berkeley, California, USA
E. Bravin
CERN, Geneva, Switzerland
T.E. Lahey
SLAC, Menlo Park, California, USA
E.S.M. McCrory
Fermilab, Batavia, USA
R. Miyamoto
ESS, Lund, Sweden
S.M. White
BNL, Upton, Long Island, New York, USA

Funding: This work partially supported by the US Department of Energy through the US LHC Accelerator Research Program (LARP).
The BRAN Ionization Chambers installed at the IP1 and IP5 Interaction Points of the LHC provide a relative measurement of the total and bunch-by-bunch luminosities. This information, combined with the logged bunch charges from a fast BCT monitor, offers the possibility of evaluating the Interaction Area in collision for each of the colliding bunch pairs and monitor its time evolution. A Graphic User Interface (GUI) has been implemented to display the interaction area of the proton bunches interacting in IP1 and IP5 during each of the Physics Runs in the attempt of displaying the contribution to the Luminosity time decay originating from possible emittance blow-up when operating the Accelerator close to the beam-beam limit. Early results confirm the ability to characterize the bunch by bunch emittance behavior during the store and study possible differences among bunches in the same fill.

TUOAB02

Investigation of the Use of Silicon, Diamond and Liquid Helium Detectors for Beam Loss Measurements at 2 Kelvin

cryogenics, radiation, proton, electron

1080

C. Kurfuerst, B. Dehning, W.T. Eisel, M. Sapinski
CERN, Geneva, Switzerland
V. Eremin
IOFFE, St. Petersburg, Russia
C. Fabjan
HEPHY, Wien, Austria

At the triplet magnets, close to the interaction regions of the LHC, the current Beam Loss Monitoring (BLM) system is very sensitive to the debris from the collisions. For future beams with higher energy and higher luminosity this will lead to a situation in which the BLM system can no longer distinguish between these interaction products and quench-provoking beam losses from the primary proton beams. The solution investigated is to locate the detectors as close as possible to the superconducting coil, i.e. the element to be protected. This means putting detectors inside the cold mass of the superconducting magnets at 1.9 K. As possible candidates for such loss monitors, diamond, silicon and a liquid helium chamber have been tested in a proton beam at liquid helium temperatures. The initial promising results from these tests will be presented and discussed in this contribution.

Slides TUOAB02 [3.412 MB]

TUOBC02

Small-Beta Collimation at SuperKEKB to Stop Beam-Gas Scattered Particles and to Avoid Transverse Mode Coupling Instability

impedance, scattering, coupling, simulation

1104

H. Nakayama, Y. Funakoshi, K. Kanazawa, K. Ohmi, Y. Ohnishi, Y. Suetsugu
KEK, Tsukuba, Japan
H. Nakano
Tohoku University, Graduate School of Science, Sendai, Japan

At SuperKEKB, beam particles which are Coulomb-scattered by the residual gas molecular change direction and will be eventually lost by hitting beam pipe inner wall. Due to large vertical beta function and small beam pipe radius just before IP, most of Coulomb-scattered particles are lost there and are very dangerous for the Belle-II detector. To stop such particles before the IP, vertical collimators are installed in the ring. However, such vertical collimators should be placed very close (few mm) to the beam and therefore induce transverse mode coupling instability. To avoid beam instability and achieve collimation at the same time, we need to install vertical collimators where vertical beta function is SMALL, since maximum collimator width determined by aperture condition is proportional to β^1/2, and minimum collimator width determined by instability is proportional to β^2/3. We present our strategy to stop beam-gas scattered particles and simulated loss rate in the interaction region. We will also show dedicated vertical collimator design to achieve less instability.

Slides TUOBC02 [2.196 MB]

WEPPD031

A Transverse Electron Target for Heavy Ion Storage Rings

electron, target, ion, simulation

2573

S. Geyer, O. Meusel
IAP, Frankfurt am Main, Germany
O.K. Kester
GSI, Darmstadt, Germany

Funding: supported by HIC for FAIR
A transverse electron target is a well suited concept for storage rings to investigate electron-ion interactions processes relevant for heavy ion accelerators. In comparison with an internal gas target, it promises a better energy resolution but still has the advantage, in contrast to an electron cooler, of access to the interaction region for photon and electron spectroscopy under large solid angles. The new electron target is suited for the use under the UHV requirements of a storage ring and realizes an open geometry for spectroscopy. A simple design based on electrostatic fields was chosen. The sheet beam application provides a higher perveance limit and a smaller potential depression than a cylindrical gun arrangement. The adjustable electron energy ranges between several 10eV and a few keV. The setup will be installed applying the so-called animated beam technique. The electron target is dedicated to the NESR at the new FAIR facility. First measurements are planned at a test bench and subsequent tests at the Frankfurt Low Energy Storage Ring (FLSR) are envisaged. An overview of the progress in the development of the transverse electron target will be given.

WEPPD037

Shielding of Superconducting Coils for a 4-MW Muon-Collider Target System

shielding, target, collider, factory

2591

R.J. Weggel, N. Souchlas
Particle Beam Lasers, Inc., Northridge, California, USA
X.P. Ding
UCLA, Los Angeles, California, USA
V.B. Graves
ORNL, Oak Ridge, Tennessee, USA
H.G. Kirk, H. K. Sayed
BNL, Upton, Long Island, New York, USA
K.T. McDonald
PU, Princeton, New Jersey, USA

Funding: Work support by the U.S. Department of Energy in part under Award No. DE-AC02-98CH10886
The target system envisioned for a Muon Collider/Neutrino Factory features a liquid Hg jet target immersed in a 20-T solenoidal field. Field quality limits intercoil gaps to ~ 40% of the O.D. of the flanking coils. Longitudinal sag of the tungsten shielding vessels limits their length to ~ 7 m. Support members adequate to resist intercryostat axial forces require an aggregate cross section of ~ 0.1 m²; the cryogenic heat leakage may be large. The innermost shielding vessel wall can be adequately cooled by helium gas only if its pressure is ~ 10 atm and its velocity is ~ 200m/s. However, the analysis in this paper found none of these engineering challenges to be insurmountable.

THPPC065

Phase and Frequency Locked Magnetron

cavity, shielding, controls, cathode

3440

M.L. Neubauer, A. Dudas, R. Sah
Muons, Inc, Batavia, USA
A. Moretti, M. Popovic
Fermilab, Batavia, USA

Funding: Supported in part by SBIR Grant 4724 · 09SC02766
Phase and Frequency locked magnetrons have many important uses from phased array ground penetrating radars to SRF sources. We report on the recent progress in making such a magnetron. The ferrite/garnet material has passed bakeout and outgassing tests with outgassing rates well below the requirements. The magnetic field requirements for adjusting the frequency by changing the microwave properties of the ferrite/garnet have been determined. The design of the anode structure with ferrites, magnetic shielding, and magnetic bias has been completed for a low power test. We report on the design status. Muons, Inc. has negotiated an contract with a manufacturing firm, L-3 Electron Devices California Tube Laboratory, Inc., to be the Manufacturing Partner for the commercialization of this technology and support these Phase II efforts.

THPPD023

Solenoid Field Calculation of the SuperKEKB Interaction Region

solenoid, quadrupole, superconducting-magnet, optics

3548

N. Ohuchi, Y. Arimoto, M. Iwasaki, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, M. Tawada, K. Tsuchiya, H. Yamaoka
KEK, Ibaraki, Japan

The SuperKEKB is the electron-positron collider, and the target luminosity is 8×10³⁵ cm^-2s⁻¹, which is 40 times larger than the attained luminosity of KEKB. The beam final focus system consists of many types of superconducting magnets as 8 quadrupoles, 40 correctors and 4 compensation solenoids. These focusing magnets and correctors are designed to be operated inside the particle detector, Belle, and under the solenoid field of 1.5 T. From the analysis of beam optics, the solenoid field profile has serious impact on the beam vertical emittance. We designs the solenoid field profile along the Belle axis in a 2-dimensional model as the first step, and now we developed this model to the 3-dimensional calculation in detail. The solenoid field profiles along the both beam lines are generated with the combine solenoid field by the Belle solenoid and the compensation solenoids, and the magnetic components of the magnets and the magnetic shields on the beam lines. The model is very complicate. From the calculation results, we will discuss the influence on the beam optics and the final focusing magnet system.