Tamar Thesis CEBAF - Revision history

Didbtama: /* Notes */

2012-12-10T06:46:43Z

Notes

Didbtama at 17:11, 23 May 2012

2012-05-23T17:11:09Z

Didbtama at 17:06, 23 May 2012

2012-05-23T17:06:48Z

Foretony at 17:53, 10 May 2012

2012-05-10T17:53:19Z

Didbtama: /* Notes */

2012-05-10T16:12:26Z

Notes

Didbtama at 16:08, 10 May 2012

2012-05-10T16:08:43Z

Foretony at 03:57, 9 May 2012

2012-05-09T03:57:26Z

Foretony at 03:51, 9 May 2012

2012-05-09T03:51:13Z

Didbtama at 14:17, 8 May 2012

2012-05-08T14:17:41Z

Didbtama at 14:05, 8 May 2012

2012-05-08T14:05:42Z

← Older revision		Revision as of 06:46, 10 December 2012
Line 41:		Line 41:

	[[Delta_D_over_D]]		[[Delta_D_over_D]]
		+
		+	[https://wiki.iac.isu.edu/index.php/SIDIS_PionAsym_EG2000 Go Back]

@@ Line 34: / Line 34: @@
 |}<br>
 Polarized electron beams are created at JLab using a GaAs photocathode. The polarized electrons are produced by bandgap photoemission from a strained GaAs cathode using a tunable Ti-Saphire laser having wavelengths from 780 to 850 nm with at least 500mW of output power<ref name="HansknechtPoelker2006> Hansknecht*, J. and Poelker, M. (2006).  Synchronous photoinjection using a frequency-doubled gain-switched fiber-coupled seed laser and ErYb-doped fiber amplifier. Phys. Rev. ST Accel. Beams '''9''', 063501.</ref>. When the cathode is exposed to circularly polarized laser light, polarized electrons move from the valence region to the conduction band. In order to free the electrons from the conduction band, the surface of the GaAs cathode is coated with a single layer of cesium and fluorine. As a result, electrons in the conduction band are bound to the surface of the material by only 4 eV. For the EG1b experiment, the direction of the electron polarization was flipped with a frequency of 1 Hz by reversing the laser polarization using a pockel cell. The electron beam polarization for each hall can be changed with a Wien Filter, it can rotate electron spin without changing its momentum. <ref name="Engwall1992"> Engwall, D.A., et al. (1992). A spin manipulator for electron accelerators. '''CEBAF-PR-92-019'''</ref><br>
-The electron beam quality during the experiment  is monitored with several devices: Mott polarimeter, Moller polarimeter, faraday cup and harp scan. The beam polarization is monitored using a 5 MeV Mott polarimeter at the injector and a Moller polarimeter in Hall B, which is located upstream to the target position. The average electron beam polarization during the EG1b experiment measured by the Hall B moller polarimeter to be  (<math>70\pm5</math>)% <ref name="Grun1997> Grún, E.; Krúger, H.; Dermott, S.; Fechtig, H.; Graps, A. L.; Zook, H. A.; Gustafson, B. A.; Hamilton, D. P.; Hanner, M. S.; Heck, A.; Horányi, M.; Kissel, J.; Lindbad, B. A.; Linkert, D.; Linkert, G.; Mann, I.; Mcdonnell, J. A. M.; Morfill, G. E.; Polanskey, C.; Schwehm, G.; Srama, R. (1997).  A double-arm Møller Polarimeter for Jefferson Lab's Hall B. Geophysical Research Letters, v. 24, No. '''17''', p. 2171.</ref>. Whereas, the integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored using beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires that measures the beam charge when swept through the beam. <br>
+The electron beam quality during the experiment  is monitored with several devices: Mott polarimeter, Moller polarimeter, faraday cup and harp scan. The beam polarization is monitored using a 5 MeV Mott polarimeter at the injector and a Moller polarimeter in Hall B, which is located upstream to the target position. The average electron beam polarization during the EG1b experiment measured by the Hall B moller polarimeter to be  (<math>70\pm5</math>)% <ref name="Grun1997> Grún, E. Krúger, H. Dermott, S. Fechtig, H. Graps, A. L. Zook, H. A. Gustafson, B. A. Hamilton, D. P. Hanner, M. S. Heck, A. Horányi, M. Kissel, J. Lindbad, B. A. Linkert, D. Linkert, G. Mann, I. Mcdonnell, J. A. M. Morfill, G. E. Polanskey, C. Schwehm, G. Srama, R. (1997).  A double-arm Møller Polarimeter for Jefferson Lab's Hall B. Geophysical Research Letters, v. 24, No. '''17''', p. 2171.</ref> <ref name="Raue1998>B. A. Raue, L. H. Kramer, R. M. Chasteler, S. J. Gaff, J. Kelly, C. Laymon, M. Spraker, H. Weller, D. S. Carman, S. Boiarinov, V. Burkert, A. Freyberger. (1998). A double-arm Møller Polarimeter for Jefferson Lab's Hall B. Bull. Am. Phys. Soc., '''43''', 1543.</ref>. Whereas, the integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored using beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires that measures the beam charge when swept through the beam. <br>
 =Notes=

@@ Line 34: / Line 34: @@
 |}<br>
 Polarized electron beams are created at JLab using a GaAs photocathode. The polarized electrons are produced by bandgap photoemission from a strained GaAs cathode using a tunable Ti-Saphire laser having wavelengths from 780 to 850 nm with at least 500mW of output power<ref name="HansknechtPoelker2006> Hansknecht*, J. and Poelker, M. (2006).  Synchronous photoinjection using a frequency-doubled gain-switched fiber-coupled seed laser and ErYb-doped fiber amplifier. Phys. Rev. ST Accel. Beams '''9''', 063501.</ref>. When the cathode is exposed to circularly polarized laser light, polarized electrons move from the valence region to the conduction band. In order to free the electrons from the conduction band, the surface of the GaAs cathode is coated with a single layer of cesium and fluorine. As a result, electrons in the conduction band are bound to the surface of the material by only 4 eV. For the EG1b experiment, the direction of the electron polarization was flipped with a frequency of 1 Hz by reversing the laser polarization using a pockel cell. The electron beam polarization for each hall can be changed with a Wien Filter, it can rotate electron spin without changing its momentum. <ref name="Engwall1992"> Engwall, D.A., et al. (1992). A spin manipulator for electron accelerators. '''CEBAF-PR-92-019'''</ref><br>
-The electron beam quality during the experiment  is monitored with several devices: Mott polarimeter, Moller polarimeter, faraday cup and harp scan. The beam polarization is monitored using a 5 MeV Mott polarimeter at the injector and a Moller polarimeter in Hall B, which is located upstream to the target position. The average electron beam polarization during the EG1b experiment measured by the Hall B moller polarimeter to be  (<math>70\pm5</math>)%. Whereas, the integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored using beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires that measures the beam charge when swept through the beam. <br>
+The electron beam quality during the experiment  is monitored with several devices: Mott polarimeter, Moller polarimeter, faraday cup and harp scan. The beam polarization is monitored using a 5 MeV Mott polarimeter at the injector and a Moller polarimeter in Hall B, which is located upstream to the target position. The average electron beam polarization during the EG1b experiment measured by the Hall B moller polarimeter to be  (<math>70\pm5</math>)% <ref name="Grun1997> Grún, E.; Krúger, H.; Dermott, S.; Fechtig, H.; Graps, A. L.; Zook, H. A.; Gustafson, B. A.; Hamilton, D. P.; Hanner, M. S.; Heck, A.; Horányi, M.; Kissel, J.; Lindbad, B. A.; Linkert, D.; Linkert, G.; Mann, I.; Mcdonnell, J. A. M.; Morfill, G. E.; Polanskey, C.; Schwehm, G.; Srama, R. (1997).  A double-arm Møller Polarimeter for Jefferson Lab's Hall B. Geophysical Research Letters, v. 24, No. '''17''', p. 2171.</ref>. Whereas, the integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored using beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires that measures the beam charge when swept through the beam. <br>
   There should be either CLAS note or NIM publication on the Moller polarimeter and the hard scanner, I am not sure if there is one for the FC.

@@ Line 35: / Line 35: @@
 Polarized electron beams are created at JLab using a GaAs photocathode. The polarized electrons are produced by bandgap photoemission from a strained GaAs cathode using a tunable Ti-Saphire laser having wavelengths from 780 to 850 nm with at least 500mW of output power<ref name="HansknechtPoelker2006> Hansknecht*, J. and Poelker, M. (2006).  Synchronous photoinjection using a frequency-doubled gain-switched fiber-coupled seed laser and ErYb-doped fiber amplifier. Phys. Rev. ST Accel. Beams '''9''', 063501.</ref>. When the cathode is exposed to circularly polarized laser light, polarized electrons move from the valence region to the conduction band. In order to free the electrons from the conduction band, the surface of the GaAs cathode is coated with a single layer of cesium and fluorine. As a result, electrons in the conduction band are bound to the surface of the material by only 4 eV. For the EG1b experiment, the direction of the electron polarization was flipped with a frequency of 1 Hz by reversing the laser polarization using a pockel cell. The electron beam polarization for each hall can be changed with a Wien Filter, it can rotate electron spin without changing its momentum. <ref name="Engwall1992"> Engwall, D.A., et al. (1992). A spin manipulator for electron accelerators. '''CEBAF-PR-92-019'''</ref><br>
 The electron beam quality during the experiment  is monitored with several devices: Mott polarimeter, Moller polarimeter, faraday cup and harp scan. The beam polarization is monitored using a 5 MeV Mott polarimeter at the injector and a Moller polarimeter in Hall B, which is located upstream to the target position. The average electron beam polarization during the EG1b experiment measured by the Hall B moller polarimeter to be  (<math>70\pm5</math>)%. Whereas, the integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored using beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires that measures the beam charge when swept through the beam. <br>
 =Notes=

← Older revision		Revision as of 16:12, 10 May 2012
Line 39:		Line 39:
	<references/>		<references/>

−	~~http://www.jlab.org/div_dept/admin/publications/papers/92/PR92-019.pdf~~

	[[Delta_D_over_D]]		[[Delta_D_over_D]]

@@ Line 34: / Line 34: @@
 |}<br>
 Polarized electron beams are created at JLab using a GaAs photocathode. The polarized electrons are produced by bandgap photoemission from a strained GaAs cathode using a tunable Ti-Saphire laser having wavelengths from 780 to 850 nm with at least 500mW of output power<ref name="HansknechtPoelker2006> Hansknecht*, J. and Poelker, M. (2006).  Synchronous photoinjection using a frequency-doubled gain-switched fiber-coupled seed laser and ErYb-doped fiber amplifier. Phys. Rev. ST Accel. Beams '''9''', 063501.</ref>. When the cathode is exposed to circularly polarized laser light, polarized electrons move from the valence region to the conduction band. In order to free the electrons from the conduction band, the surface of the GaAs cathode is coated with a single layer of cesium and fluorine. As a result, electrons in the conduction band are bound to the surface of the material by only 4 eV. For the EG1b experiment, the direction of the electron polarization was flipped with a frequency of 1 Hz by reversing the laser polarization using a pockel cell. The electron beam polarization for each hall can be changed with a Wien Filter, it can rotate electron spin without changing its momentum. <ref name="Engwall1992"> Engwall, D.A., et al. (1992). A spin manipulator for electron accelerators. '''CEBAF-PR-92-019'''</ref><br>
 The beam polarization is monitored using a 5 MeV Mott polarimeter and a Moller polarimeter in Hall B. The average electron beam polarization during the EG1b experiment was measured by the Hall B moller polarimeter to be  (<math>70\pm5</math>)%. <br>
-The integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored with a three beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires moved around the beam. <br>
+The integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored using beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires that measure the beam charge when swept through the beam. <br>
 =Notes=

@@ Line 33: / Line 33: @@
 |'''Table 1.''' The CEBAF accelerator parameters <ref name="Grunder1987"> Grunder, H.A., et al. (1987). The Continuous Electron Beam Accelerator Facility. '''CEBAF-PR-87-017'''.</ref>
 |}<br>
-Polarized electron beams are created at JLab using a GaAs photocathode. The polarized electrons are produced by bandgap photoemission from a strained GaAs cathode using a tunable Ti-Saphire laser having wavelengths from 780 to 850 nm with at least 500mW of output power<ref name="HansknechtPoelker2J. Hansknecht* and M. Poelker, PHYSICAL REVIEW SPECIAL TOPICS - ACCELERATORS AND BEAMS 9, 063501 (2006)</ref>. When the cathode is exposed to circularly polarized laser light, polarized electrons move from the valence region to the conduction band. In order to free the electrons from the conduction band, the surface of the GaAs cathode is coated with a single layer of cesium and fluorine. As a result, electrons in the conduction band are bound to the surface of the material by only 4 eV. For the EG1b experiment, the direction of the electron polarization was flipped with a frequency of 1 Hz by reversing the laser polarization using a pockel cell. The electron beam polarization for each hall can be changed with a Wien Filter, it can rotate electron spin without changing its momentum. <ref name="Engwall1992"> Engwall, D.A., et al. (1992). A spin manipulator for electron accelerators. '''CEBAF-PR-92-019'''</ref><br>
+Polarized electron beams are created at JLab using a GaAs photocathode. The polarized electrons are produced by bandgap photoemission from a strained GaAs cathode using a tunable Ti-Saphire laser having wavelengths from 780 to 850 nm with at least 500mW of output power<ref name="HansknechtPoelker2006> Hansknecht*, J. and Poelker, M. (2006).  Synchronous photoinjection using a frequency-doubled gain-switched fiber-coupled seed laser and ErYb-doped fiber amplifier. Phys. Rev. ST Accel. Beams '''9''', 063501.</ref>. When the cathode is exposed to circularly polarized laser light, polarized electrons move from the valence region to the conduction band. In order to free the electrons from the conduction band, the surface of the GaAs cathode is coated with a single layer of cesium and fluorine. As a result, electrons in the conduction band are bound to the surface of the material by only 4 eV. For the EG1b experiment, the direction of the electron polarization was flipped with a frequency of 1 Hz by reversing the laser polarization using a pockel cell. The electron beam polarization for each hall can be changed with a Wien Filter, it can rotate electron spin without changing its momentum. <ref name="Engwall1992"> Engwall, D.A., et al. (1992). A spin manipulator for electron accelerators. '''CEBAF-PR-92-019'''</ref><br>
 The beam polarization is monitored using a 5 MeV Mott polarimeter and a Moller polarimeter in Hall B. The average electron beam polarization achieved during the EG1b experiment was around (<math>70\pm5</math>)%. <br>
 The integrated electron beam current is measured using a Farady cup.  The Faraday cup is located downstream of the CLAS target and contains several layers of lead and scintillator in order to create a large amount of detected secondary particles from the primary electron beam. The position of the beam is monitored with a three beam position monitors. The profile of the beam is monitored with a harp scan, a device with thin iron and tungsten wires moved around the beam. <br>