M. Sasao, M. Nishiura, S. Guharay, T. Kuroda, M. Hamabe, H. Ramos
A test stand with a multicusp type He/sup +/ ion source and an electrostatic transport system was built for the study of beam characteristics at relatively low energy, E<10 keV, and beam transport in a space-charge dominated region with /spl beta/(=v/c)<0.0025. The measured normalized beam emittance (90%) of the He/sup +/ beam extracted from a compact multicusp source is about 0.08 /spl pi/ mm-mrad for the emission current density of about 5-15 mA/cm/sup 2/ at 6-9 kV. An electrostatic quadrupole transport system (ESQ) is designed for this beam. Preliminary experimental results show that the ESQ has a potential to transport a beam without any significant emittance growth over a length of about 50 cm.
{"title":"Characteristics of helium ion beams from multicusp source and study of beam transport","authors":"M. Sasao, M. Nishiura, S. Guharay, T. Kuroda, M. Hamabe, H. Ramos","doi":"10.1109/PAC.1999.795530","DOIUrl":"https://doi.org/10.1109/PAC.1999.795530","url":null,"abstract":"A test stand with a multicusp type He/sup +/ ion source and an electrostatic transport system was built for the study of beam characteristics at relatively low energy, E<10 keV, and beam transport in a space-charge dominated region with /spl beta/(=v/c)<0.0025. The measured normalized beam emittance (90%) of the He/sup +/ beam extracted from a compact multicusp source is about 0.08 /spl pi/ mm-mrad for the emission current density of about 5-15 mA/cm/sup 2/ at 6-9 kV. An electrostatic quadrupole transport system (ESQ) is designed for this beam. Preliminary experimental results show that the ESQ has a potential to transport a beam without any significant emittance growth over a length of about 50 cm.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"117 1","pages":"1306-1308 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2013-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87069409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Hendrickson, P. Grossberg, T. Himel, M. Minty, N. Phinney, P. Raimondi, T. Raubenheimer, H. Shoaee, P. Tenenbaum
Feedback systems are essential for stable operation of a linear collider, providing a cost-effective method for relaxing tight tolerances. In the Stanford Linear Collider (SLC), feedback controls beam parameters such as trajectory, energy, and intensity throughout the accelerator. A novel dithering optimization system which adjusts final focus parameters to maximize luminosity contributed to achieving record performance in the 1997-98 run. Performance limitations of the steering feedback have been investigated, and improvements have been made. For the Next Linear Collider (NLC), extensive feedback systems are planned as an integral part of the design. Feedback requirements for JLC (the Japanese Linear Collider) are essentially identical to NLC; some of the TESLA requirements are similar but there are significant differences. For NLC, algorithms which incorporate improvements upon the SLC implementation are being prototyped. Specialized systems for the damping rings, RF and interaction point will operate at high bandwidth and fast response. To correct for the motion of individual bunches within a train, both feedforward and feedback systems are planned. SLC experience has shown that feedback systems are an invaluable operational tool for decoupling systems, allowing precision tuning, and providing pulse-to-pulse diagnostics. Feedback systems for the NLC will incorporate the key SLC features and the benefits of advancing technologies.
{"title":"Feedback systems for linear colliders","authors":"L. Hendrickson, P. Grossberg, T. Himel, M. Minty, N. Phinney, P. Raimondi, T. Raubenheimer, H. Shoaee, P. Tenenbaum","doi":"10.1109/PAC.1999.795699","DOIUrl":"https://doi.org/10.1109/PAC.1999.795699","url":null,"abstract":"Feedback systems are essential for stable operation of a linear collider, providing a cost-effective method for relaxing tight tolerances. In the Stanford Linear Collider (SLC), feedback controls beam parameters such as trajectory, energy, and intensity throughout the accelerator. A novel dithering optimization system which adjusts final focus parameters to maximize luminosity contributed to achieving record performance in the 1997-98 run. Performance limitations of the steering feedback have been investigated, and improvements have been made. For the Next Linear Collider (NLC), extensive feedback systems are planned as an integral part of the design. Feedback requirements for JLC (the Japanese Linear Collider) are essentially identical to NLC; some of the TESLA requirements are similar but there are significant differences. For NLC, algorithms which incorporate improvements upon the SLC implementation are being prototyped. Specialized systems for the damping rings, RF and interaction point will operate at high bandwidth and fast response. To correct for the motion of individual bunches within a train, both feedforward and feedback systems are planned. SLC experience has shown that feedback systems are an invaluable operational tool for decoupling systems, allowing precision tuning, and providing pulse-to-pulse diagnostics. Feedback systems for the NLC will incorporate the key SLC features and the benefits of advancing technologies.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"79 1","pages":"338-342 vol.1"},"PeriodicalIF":0.0,"publicationDate":"2001-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77193647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A conceptual design study for a vacuum system for a possible compact high luminosity upgrade to CESR is presented. The vacuum chamber consists of an elliptical cross-section beam chamber connected to a pumping chamber by holes recessed in several channels in the beam chamber wall. Recessing the hole provides a decrease in the impedance of the beam chamber while still providing protection to the pumping chamber from RF fields generated by the beam. The beam chamber has a very compact cross-section compatible with two-in-one quadrupole magnets and inexpensive compact dipole magnets. Pumping will be provided by a combination of nonevaporable getter (NEG) and ion pumps. Calculations were carried out of the impedance and loss factor of the chamber as well as transmission of RF field power through the slots and the conductance of the pumping slots. We have also calculated the linear synchrotron radiation power density and the pressure profile and beam-gas lifetime for this chamber and pump configuration. We consider the time between necessary NEG pump reactivations and the total capacity of the pumps.
{"title":"Conceptual design of a vacuum system for a compact, high luminosity CESR upgrade","authors":"K. Ormond, J. Rogers","doi":"10.1109/PAC.1999.795546","DOIUrl":"https://doi.org/10.1109/PAC.1999.795546","url":null,"abstract":"A conceptual design study for a vacuum system for a possible compact high luminosity upgrade to CESR is presented. The vacuum chamber consists of an elliptical cross-section beam chamber connected to a pumping chamber by holes recessed in several channels in the beam chamber wall. Recessing the hole provides a decrease in the impedance of the beam chamber while still providing protection to the pumping chamber from RF fields generated by the beam. The beam chamber has a very compact cross-section compatible with two-in-one quadrupole magnets and inexpensive compact dipole magnets. Pumping will be provided by a combination of nonevaporable getter (NEG) and ion pumps. Calculations were carried out of the impedance and loss factor of the chamber as well as transmission of RF field power through the slots and the conductance of the pumping slots. We have also calculated the linear synchrotron radiation power density and the pressure profile and beam-gas lifetime for this chamber and pump configuration. We consider the time between necessary NEG pump reactivations and the total capacity of the pumps.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"5 1","pages":"1354-1356 vol.2"},"PeriodicalIF":0.0,"publicationDate":"2001-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80075647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Semertzidis, V. Castillo, R. Larsen, D. M. Lazatus, B. Magurno, T. Srinivasan-Rao, T. Tsang, V. Usack, L. Kowalski, D. E. Kraus
We have made the first observation of a charged particle beam by means of its electro-optical effect on the propagation of laser light in a birefringent crystal at the Brookhaven National Laboratory Accelerator Test Facility. Polarized infrared light was coupled to a LiNbO/sub 3/ crystal through a polarization maintaining fiber of 4 micron diameter. An electron beam in 10 ps bunches of 1 mm diameter was scanned across the crystal. The modulation of the laser light during passage of the electron beam was observed using a photodiode with 45 GHz bandwidth. The fastest rise time measured, 120 ps, was made in the single shot mode and was limited by the bandwidth of the oscilloscope and the associated electronics. Both polarization dependent and polarization independent effects were observed. This technology holds promise of greatly improved spatial and temporal resolution of charged particle beams.
{"title":"Electro-optical detection of charged particle beams","authors":"Y. Semertzidis, V. Castillo, R. Larsen, D. M. Lazatus, B. Magurno, T. Srinivasan-Rao, T. Tsang, V. Usack, L. Kowalski, D. E. Kraus","doi":"10.1109/PAC.1999.795740","DOIUrl":"https://doi.org/10.1109/PAC.1999.795740","url":null,"abstract":"We have made the first observation of a charged particle beam by means of its electro-optical effect on the propagation of laser light in a birefringent crystal at the Brookhaven National Laboratory Accelerator Test Facility. Polarized infrared light was coupled to a LiNbO/sub 3/ crystal through a polarization maintaining fiber of 4 micron diameter. An electron beam in 10 ps bunches of 1 mm diameter was scanned across the crystal. The modulation of the laser light during passage of the electron beam was observed using a photodiode with 45 GHz bandwidth. The fastest rise time measured, 120 ps, was made in the single shot mode and was limited by the bandwidth of the oscilloscope and the associated electronics. Both polarization dependent and polarization independent effects were observed. This technology holds promise of greatly improved spatial and temporal resolution of charged particle beams.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"20 1","pages":"490-491 vol.1"},"PeriodicalIF":0.0,"publicationDate":"2000-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75045357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G.N. Kim, H. Kang, J. Choi, M. Cho, I. Ko, W. Namkung, J. Chang
The Pohang Accelerator Laboratory uses a 100-MeV electron linac for the pulsed neutron source as one of the long-term nuclear R&D programs at the Korea Atomic Energy Research Institute. The linac has two operating modes; one for short pulse mode with the various repetitions between 2 ns and 100 ns and the other for long pulse mode with 1 /spl mu/s. The major beam parameters are as follows; the nominal beam energy is 100 MeV, the maximum beam power is 10 kW, and the beam current is varied from 300 mA to 5 A and depends on the pulse repetition. We constructed and tested a test-linac based on the existing equipment such as a SLAC-5045 klystron, two constant gradient accelerating sections, and thermionic RF-gun. We describe the characteristics of the test-linac and report the status of the pulsed neutron source facilities including a target system and time-off-flight paths.
{"title":"Pulsed neutron source using 100-MeV electron linac at Pohang Accelerator Laboratory","authors":"G.N. Kim, H. Kang, J. Choi, M. Cho, I. Ko, W. Namkung, J. Chang","doi":"10.1109/PAC.1999.792788","DOIUrl":"https://doi.org/10.1109/PAC.1999.792788","url":null,"abstract":"The Pohang Accelerator Laboratory uses a 100-MeV electron linac for the pulsed neutron source as one of the long-term nuclear R&D programs at the Korea Atomic Energy Research Institute. The linac has two operating modes; one for short pulse mode with the various repetitions between 2 ns and 100 ns and the other for long pulse mode with 1 /spl mu/s. The major beam parameters are as follows; the nominal beam energy is 100 MeV, the maximum beam power is 10 kW, and the beam current is varied from 300 mA to 5 A and depends on the pulse repetition. We constructed and tested a test-linac based on the existing equipment such as a SLAC-5045 klystron, two constant gradient accelerating sections, and thermionic RF-gun. We describe the characteristics of the test-linac and report the status of the pulsed neutron source facilities including a target system and time-off-flight paths.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"37 1","pages":"2593-2595 vol.4"},"PeriodicalIF":0.0,"publicationDate":"2000-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79440286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Huang, M. Bai, G. Bunce, Y. Makdisi, T. Roser, K. Imai, M. Nakamura, J. Tojo, K. Yamamoto, L. Zhu, B. Bassalleck, S. Eilerts, D. Fields, B. Lewis, B. Smith, T. Thomas, D. Wolfe, Y. Goto, N. Hayoshi, M. Ishihara, K. Kurita, M. Okamura, N. Saito, A. Taketani, D. Underwood, J. Doskow, K. Kwiatkowski, B. Lozowski, H. Meyer, B. Przewoski, T. Rinckel, S. Nurushev, M. Strikhanov, M. F. Runtzo, I. Alekseev, D. Svirida, A. Deshpande, V. Hughes
The RHIC spin program requires excellent polarimetry so that the knowledge of the beam polarization does not limit the errors on the experimental measurements. However, polarimetry of proton beams with energies higher than about 30 GeV poses a difficult challenge. For polarization monitoring during operation, a fast and reliable polarimeter is required that produces a polarization measurement with a 10% relative error within a few minutes. The p-carbon elastic scattering in the Coulomb-nuclear-scattering (CNI) region has a calculable and large analyzing power, but detecting the recoil carbon needs a sophisticated detector system and a very thin target. An experiment has been planned in the AGS. This paper describes the experimental setup in the AGS.
{"title":"A p-carbon CNI polarimeter for RHIC","authors":"H. Huang, M. Bai, G. Bunce, Y. Makdisi, T. Roser, K. Imai, M. Nakamura, J. Tojo, K. Yamamoto, L. Zhu, B. Bassalleck, S. Eilerts, D. Fields, B. Lewis, B. Smith, T. Thomas, D. Wolfe, Y. Goto, N. Hayoshi, M. Ishihara, K. Kurita, M. Okamura, N. Saito, A. Taketani, D. Underwood, J. Doskow, K. Kwiatkowski, B. Lozowski, H. Meyer, B. Przewoski, T. Rinckel, S. Nurushev, M. Strikhanov, M. F. Runtzo, I. Alekseev, D. Svirida, A. Deshpande, V. Hughes","doi":"10.1109/PAC.1999.795735","DOIUrl":"https://doi.org/10.1109/PAC.1999.795735","url":null,"abstract":"The RHIC spin program requires excellent polarimetry so that the knowledge of the beam polarization does not limit the errors on the experimental measurements. However, polarimetry of proton beams with energies higher than about 30 GeV poses a difficult challenge. For polarization monitoring during operation, a fast and reliable polarimeter is required that produces a polarization measurement with a 10% relative error within a few minutes. The p-carbon elastic scattering in the Coulomb-nuclear-scattering (CNI) region has a calculable and large analyzing power, but detecting the recoil carbon needs a sophisticated detector system and a very thin target. An experiment has been planned in the AGS. This paper describes the experimental setup in the AGS.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"10 1","pages":"471-473 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76946740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Aoki, J. Yang, M. Yorozu, Y. Okada, S. Endo, T. Kozawa, Y. Yoshida, S. Tagawa, M. Washio, X. Wang, I. Ben-Zvi
The performance tests were done for a 1.6 cell s-band BNL-type photocathode RF electron gun, GUN-IV, under a condition of 1.5 MW RF power input and 266 nm Nd:YAG laser pulse irradiation. As a result, the maximum energy and the maximum charge/bunch were obtained as 1.6 MeV and 120 pC/bunch, respectively. In addition, a sinusoidal behavior of current with the polarization angle of laser light were measured. Furthermore, the change in current as a function of laser injection phase was measured and reasonably reproduced by a numerical calculation.
{"title":"A high-duty 1.6 cell s-band RF gun driven by a psec Nd:YAG laser","authors":"Y. Aoki, J. Yang, M. Yorozu, Y. Okada, S. Endo, T. Kozawa, Y. Yoshida, S. Tagawa, M. Washio, X. Wang, I. Ben-Zvi","doi":"10.1109/PAC.1999.794358","DOIUrl":"https://doi.org/10.1109/PAC.1999.794358","url":null,"abstract":"The performance tests were done for a 1.6 cell s-band BNL-type photocathode RF electron gun, GUN-IV, under a condition of 1.5 MW RF power input and 266 nm Nd:YAG laser pulse irradiation. As a result, the maximum energy and the maximum charge/bunch were obtained as 1.6 MeV and 120 pC/bunch, respectively. In addition, a sinusoidal behavior of current with the polarization angle of laser light were measured. Furthermore, the change in current as a function of laser injection phase was measured and reasonably reproduced by a numerical calculation.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"11 1","pages":"2018-2020 vol.3"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86655662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Bharadwaj, J. Clendenin, P. Emma, J. Frisch, R. Jobe, T. Kotseroglou, P. Krejcik, A. Kulikov, Z. Li, T. Maruyama, K. Millage, B. McKee, G. Mulhollan, M. Munro, C. Rago, T. Raubenheimer, M. Ross, N. Phinney, D. Schultz, J. Sheppard, C. Spencer, A. Vlieks, M. Woodley, K. Van Bibber, S. Takeda
The Next Linear Collider (NLC) injector system is designed to produce low emittance, 10 GeV electron and positron beams at 120 hertz for injection into the NLC main linacs. Each beam consists of a train of 95 bunches spaced by 2.8 ns; each bunch has a population of 1.15/spl times/10/sup 10/ particles. At injection into the main linacs, the horizontal and vertical emittances are specified to be /spl gamma//spl isin//sub x/=3/spl times/10/sup 16/ m-rad and /spl gamma//spl isin//sub y/=3/spl times/10/sup -8/ m-rad and the bunch length is 100 /spl mu/m. Electron polarization of greater than 80% is required. Electron and positron beams are generated in separate accelerator complexes each of which contain the source, damping ring systems, L-band, S-band, and X-band linacs, bunch length compressors, and collimation regions. The need for low technical risk, reliable injector subsystems is a major consideration in the design effort. This paper presents an overview of the NLC injector systems.
{"title":"The NLC injector system","authors":"V. Bharadwaj, J. Clendenin, P. Emma, J. Frisch, R. Jobe, T. Kotseroglou, P. Krejcik, A. Kulikov, Z. Li, T. Maruyama, K. Millage, B. McKee, G. Mulhollan, M. Munro, C. Rago, T. Raubenheimer, M. Ross, N. Phinney, D. Schultz, J. Sheppard, C. Spencer, A. Vlieks, M. Woodley, K. Van Bibber, S. Takeda","doi":"10.1109/PAC.1999.792332","DOIUrl":"https://doi.org/10.1109/PAC.1999.792332","url":null,"abstract":"The Next Linear Collider (NLC) injector system is designed to produce low emittance, 10 GeV electron and positron beams at 120 hertz for injection into the NLC main linacs. Each beam consists of a train of 95 bunches spaced by 2.8 ns; each bunch has a population of 1.15/spl times/10/sup 10/ particles. At injection into the main linacs, the horizontal and vertical emittances are specified to be /spl gamma//spl isin//sub x/=3/spl times/10/sup 16/ m-rad and /spl gamma//spl isin//sub y/=3/spl times/10/sup -8/ m-rad and the bunch length is 100 /spl mu/m. Electron polarization of greater than 80% is required. Electron and positron beams are generated in separate accelerator complexes each of which contain the source, damping ring systems, L-band, S-band, and X-band linacs, bunch length compressors, and collimation regions. The need for low technical risk, reliable injector subsystems is a major consideration in the design effort. This paper presents an overview of the NLC injector systems.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"32 1","pages":"3447-3449 vol.5"},"PeriodicalIF":0.0,"publicationDate":"1999-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88987706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Kotserogluo, V. Bharadwaj, J. Clendenin, S. Ecklund, J. Frisch, P. Krejcik, A. Kulikov, J. Liu, T. Maruyama, K. Millage, G. Mulhollan, W. Nelson, D. Schultz, J. Sheppard, J. Turner, K. Van Bibber, K. Flottmann, Y. Namito
Recent developments in the design of the Next Linear Collider (NLC) positron source based on updated beam parameters are described. The unpolarized NLC positron source consists of a dedicated 6.2 GeV S-band electron accelerator, a high-Z positron production target, a capture system and an L-band positron linac. The 1998 failure of the SLC target which is currently under investigation may lead to a variation of the target design. Progress towards a polarized positron source is also presented. A moderately polarized positron beam colliding with a highly polarized electron beam results in an effective polarization large enough to explore new physics at NLC. One of the schemes towards a polarized positron source incorporates a polarized electron source, a 50 MeV electron accelerator, a thin target for positron production and a new capture system optimized for high-energy small angular divergence positrons.
{"title":"Recent developments in the design of the NLC positron source","authors":"T. Kotserogluo, V. Bharadwaj, J. Clendenin, S. Ecklund, J. Frisch, P. Krejcik, A. Kulikov, J. Liu, T. Maruyama, K. Millage, G. Mulhollan, W. Nelson, D. Schultz, J. Sheppard, J. Turner, K. Van Bibber, K. Flottmann, Y. Namito","doi":"10.1109/PAC.1999.792333","DOIUrl":"https://doi.org/10.1109/PAC.1999.792333","url":null,"abstract":"Recent developments in the design of the Next Linear Collider (NLC) positron source based on updated beam parameters are described. The unpolarized NLC positron source consists of a dedicated 6.2 GeV S-band electron accelerator, a high-Z positron production target, a capture system and an L-band positron linac. The 1998 failure of the SLC target which is currently under investigation may lead to a variation of the target design. Progress towards a polarized positron source is also presented. A moderately polarized positron beam colliding with a highly polarized electron beam results in an effective polarization large enough to explore new physics at NLC. One of the schemes towards a polarized positron source incorporates a polarized electron source, a 50 MeV electron accelerator, a thin target for positron production and a new capture system optimized for high-energy small angular divergence positrons.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"47 1","pages":"3450-3452 vol.5"},"PeriodicalIF":0.0,"publicationDate":"1999-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73811886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Murokh, C. Pellegrini, J. Rosenzweig, P. Frigola, P. Musumeci, A. Tremaine, M. Babzien, I. Ben-Zvi, A. Doyuran, E. Johnson, J. Skaritka, X. Wang, K. Van Bibber, J. Hill, G. Le Sage, D. Nguyen, M. Cornacchia
The VISA (Visible to Infrared SASE Amplifier) project is designed to be a SASE-FEL driven to saturation in the sub-micron wavelength region. Its goal is to test various aspects of the existing theory of self-amplified spontaneous emission, as well as numerical codes. Measurements include: angular and spectral distribution of the FEL light at the exit and inside of the undulator; electron beam micro-bunching using CTR; single-shot time resolved measurements of the pulse profile, using an auto-correlation technique and FROG algorithm. The diagnostics are designed to provide maximum information on the physics of the SASE-FEL process, to ensure a close comparison of the experimental results with theory and simulations.
{"title":"Photon beam diagnostics for VISA FEL","authors":"A. Murokh, C. Pellegrini, J. Rosenzweig, P. Frigola, P. Musumeci, A. Tremaine, M. Babzien, I. Ben-Zvi, A. Doyuran, E. Johnson, J. Skaritka, X. Wang, K. Van Bibber, J. Hill, G. Le Sage, D. Nguyen, M. Cornacchia","doi":"10.1109/PAC.1999.792736","DOIUrl":"https://doi.org/10.1109/PAC.1999.792736","url":null,"abstract":"The VISA (Visible to Infrared SASE Amplifier) project is designed to be a SASE-FEL driven to saturation in the sub-micron wavelength region. Its goal is to test various aspects of the existing theory of self-amplified spontaneous emission, as well as numerical codes. Measurements include: angular and spectral distribution of the FEL light at the exit and inside of the undulator; electron beam micro-bunching using CTR; single-shot time resolved measurements of the pulse profile, using an auto-correlation technique and FROG algorithm. The diagnostics are designed to provide maximum information on the physics of the SASE-FEL process, to ensure a close comparison of the experimental results with theory and simulations.","PeriodicalId":20453,"journal":{"name":"Proceedings of the 1999 Particle Accelerator Conference (Cat. No.99CH36366)","volume":"11 1","pages":"2480-2482 vol.4"},"PeriodicalIF":0.0,"publicationDate":"1999-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78791243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}