TJ-II:Electron Cyclotron Emission - Revision history

Admin: Updated reference links

2018-04-03T16:07:47Z

Updated reference links

← Older revision		Revision as of 18:07, 3 April 2018
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	== Calibration ==		== Calibration ==
	The system is calibrated absolutely by comparing room temperature with liquid nitrogen temperature.		The system is calibrated absolutely by comparing room temperature with liquid nitrogen temperature.
	<ref name="Luna">~~[http://link.aip.org/link/?RSINAK/72/379/1~~ E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>		<ref name="Luna">E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', [[doi:10.1063/1.1315636\|Rev. Sci. Instrum. '''72''', 379 (2001)]]</ref>
	<ref>~~[http://dx.doi.org/10.1016/S0920-3796(00)00492-0~~ E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>		<ref>E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', [[doi:10.1016/S0920-3796(00)00492-0\|Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]]</ref>
	The optical system and the transmission line of the ECE diagnostic were designed to allow the calibration to be performed outside the vacuum vessel keeping the arrangement of the diagnostic.		The optical system and the transmission line of the ECE diagnostic were designed to allow the calibration to be performed outside the vacuum vessel keeping the arrangement of the diagnostic.
	To calibrate, the transmission line is opened close to the diagnostic port (C5-bottom). Then the port flange, which holds the optical system and the wave-guide up to that point, is extracted from the torus and assembled with the same alignment outside the vacuum vessel.		To calibrate, the transmission line is opened close to the diagnostic port (C5-bottom). Then the port flange, which holds the optical system and the wave-guide up to that point, is extracted from the torus and assembled with the same alignment outside the vacuum vessel.
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	The emission can be simulated by the [[TRECE]] ray tracing code.		The emission can be simulated by the [[TRECE]] ray tracing code.
	<ref name="Tribal">~~[http://dx.doi.org/10.1088/0029-5515/36/3/I02~~ V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>		<ref name="Tribal">V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', [[doi:10.1088/0029-5515/36/3/I02\|Nucl. Fusion '''36''', 283 (1996)]]</ref>

	The local radiation temperature is assumed to be a function only of the local electron temperature at the resonant layer; however, if the plasma is not Maxwellian or if the plasma is optically thin, the measured radiation temperature is no longer equal to the electron temperature.		The local radiation temperature is assumed to be a function only of the local electron temperature at the resonant layer; however, if the plasma is not Maxwellian or if the plasma is optically thin, the measured radiation temperature is no longer equal to the electron temperature.

Admin: Added wikpedia link

2016-09-21T12:47:27Z

Added wikpedia link

← Older revision		Revision as of 14:47, 21 September 2016
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	Electron temperature profiles are measured at [[TJ-II]]		Electron temperature profiles are measured at [[TJ-II]]
	by means of a 16 channel heterodyne radiometer,		by means of a 16 channel heterodyne radiometer,
	covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.		covering the frequency range 50–60 GHz, corresponding to the second harmonic of [[:Wikipedia:Electron cyclotron resonance\|electron cyclotron]] emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.
	The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5, φ = 315°), but most of the channels receive radiation from the high field side (HFS). In normal operation conditions, the frequency depends on a known way on the magnitude of the magnetic field B. Tuning properly the receiver system, each frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').		The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5, φ = 315°), but most of the channels receive radiation from the high field side (HFS). In normal operation conditions, the frequency depends on a known way on the magnitude of the magnetic field B. Tuning properly the receiver system, each frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').
	The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).		The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).

Daniellopezbruna: Specifies that the ECE system is tuned to receive radiation mainly from the HFS of the plasma

2012-07-02T15:27:40Z

Specifies that the ECE system is tuned to receive radiation mainly from the HFS of the plasma

← Older revision		Revision as of 17:27, 2 July 2012
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	by means of a 16 channel heterodyne radiometer,		by means of a 16 channel heterodyne radiometer,
	covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.		covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.
	The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5, φ = 315°).		The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5, φ = 315°), but most of the channels receive radiation from the high field side (HFS). In normal operation conditions, the frequency depends on a known way on the magnitude of the magnetic field B. Tuning properly the receiver system, each frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').
	~~Each~~ frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').
	The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).		The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).
	To protect the radiometer against stray radiation from the gyrotron, the radiometer band is split into two parts.		To protect the radiometer against stray radiation from the gyrotron, the radiometer band is split into two parts.

Admin at 10:27, 4 February 2011

2011-02-04T10:27:45Z

← Older revision		Revision as of 12:27, 4 February 2011
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	by means of a 16 channel heterodyne radiometer,		by means of a 16 channel heterodyne radiometer,
	covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.		covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.
	The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5).		The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5, φ = 315°).
	Each frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').		Each frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').
	The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).		The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).

Admin at 09:50, 19 August 2010

2010-08-19T09:50:43Z

← Older revision		Revision as of 11:50, 19 August 2010
Line 3:		Line 3:
	by means of a 16 channel heterodyne radiometer,		by means of a 16 channel heterodyne radiometer,
	covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.		covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.
	The measurements are performed from the low field side (LFS) in the horizontal midplane ([[TJ-II:Sectors\|~~sector~~]] C4).		The measurements are performed from the low field side (LFS) in the horizontal midplane (between [[TJ-II:Sectors\|sectors]] C4 and C5).
	Each frequency corresponds to a different value of the major radius ''R''.		Each frequency corresponds to a different value of the major radius ''R'' (according to ''B(R)'').
	The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).		The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).
	To protect the radiometer against stray radiation from the gyrotron, the radiometer band is split into two parts.		To protect the radiometer against stray radiation from the gyrotron, the radiometer band is split into two parts.
	The second harmonic emission above and below 53.2 GHz are measured separately by means of microwave couplers in the signal path.		The second harmonic emission above and below 53.2 GHz are measured separately by means of microwave couplers in the signal path.

			== Calibration ==
	The system is calibrated absolutely by comparing room temperature with liquid nitrogen temperature.		The system is calibrated absolutely by comparing room temperature with liquid nitrogen temperature.
	<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>		<ref name="Luna">[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>
	<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>		<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>
			The optical system and the transmission line of the ECE diagnostic were designed to allow the calibration to be performed outside the vacuum vessel keeping the arrangement of the diagnostic.
			To calibrate, the transmission line is opened close to the diagnostic port (C5-bottom). Then the port flange, which holds the optical system and the wave-guide up to that point, is extracted from the torus and assembled with the same alignment outside the vacuum vessel.
			A check for the radiometer stability is performed periodically by using a stable noise source at the input of the radiometer. Such a noise source is also used to test the linearity of the system and to calibrate any possible change that may occur in the electronics of the diagnostic.

			== Data analysis ==

	The emission can be simulated by the [[TRECE]] ray tracing code.		The emission can be simulated by the [[TRECE]] ray tracing code.
	<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>		<ref name="Tribal">[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>

			The local radiation temperature is assumed to be a function only of the local electron temperature at the resonant layer; however, if the plasma is not Maxwellian or if the plasma is optically thin, the measured radiation temperature is no longer equal to the electron temperature.
			The effect of polarization rotation can be neglected once the correct polarization for the pure X mode on-axis is chosen. Even at high density (worst condition) the radiation coming from the plasma bulk experiences a rotation below 5°.<ref name="Tribal" />
			The spatial resolution is about 1 cm.<ref name="Luna" />

	The typical sampling rate is 100 kHz.		The typical sampling rate is 100 kHz.
	The signals ~~are called 'ECE1' ... 'ECE16'~~ in the [[TJ-II:Shot_database\|TJ-II database]].		The raw signals in the [[TJ-II:Shot_database\|TJ-II database]] are called 'ECE1' ... 'ECE16', and the processed (calibrated) signals 'TECE1_' ... 'TECE16_' (units: keV).
	~~The measured ECE amplitude is proportional to~~ the ~~electron temperature, provided certain conditions are met~~.

	== References ==		== References ==
	<references />		<references />

Admin at 11:29, 12 January 2010

2010-01-12T11:29:16Z

← Older revision		Revision as of 13:29, 12 January 2010
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			[[File:TJ-II_ECE_Antenna.png\|315px\|thumb\|right\|Diagram showing the position of the ECE antenna-mirror system at TJ-II.]]
	Electron temperature profiles are measured at [[TJ-II]]		Electron temperature profiles are measured at [[TJ-II]]
	by means of a 16 channel heterodyne radiometer,		by means of a 16 channel heterodyne radiometer,

Admin at 09:35, 28 October 2009

2009-10-28T09:35:40Z

← Older revision		Revision as of 11:35, 28 October 2009
Line 2:		Line 2:
	by means of a 16 channel heterodyne radiometer,		by means of a 16 channel heterodyne radiometer,
	covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.		covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.
	The measurements are performed from the low field side (LFS) in the horizontal midplane.		The measurements are performed from the low field side (LFS) in the horizontal midplane ([[TJ-II:Sectors\|sector]] C4).
	Each frequency corresponds to a different value of the major radius ''R''.		Each frequency corresponds to a different value of the major radius ''R''.
	The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).		The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).

Admin at 18:29, 28 September 2009

2009-09-28T18:29:03Z

← Older revision		Revision as of 20:29, 28 September 2009
Line 1:		Line 1:
	Electron ~~cyclotron emission measurements~~ are ~~routinely performed in~~ TJ-II ~~stellarator~~ by means of a ~~multichannel~~ heterodyne radiometer. The ~~radiometer is absolutely calibrated and measures~~ the ~~temperature profile with high temporal resolution~~.		Electron temperature profiles are measured at [[TJ-II]]
	~~The diagnostic provides 12 measurement channels, corresponding~~ to ~~12 values~~ of the major radius ''R''.		by means of a 16 channel heterodyne radiometer,
			covering the frequency range 50–60 GHz, corresponding to the second harmonic of electron cyclotron emission (ECE) in X-mode polarization at a magnetic field of 0.95 T on the plasma axis.
			The measurements are performed from the low field side (LFS) in the horizontal midplane.
			Each frequency corresponds to a different value of the major radius ''R''.
			The system is operated close to the strong [[TJ-II:Electron Cyclotron Resonant Heating\|ECR heating source]] (f<sub>ECRH</sub> = 53.2 GHz).
			To protect the radiometer against stray radiation from the gyrotron, the radiometer band is split into two parts.
			The second harmonic emission above and below 53.2 GHz are measured separately by means of microwave couplers in the signal path.
			The system is calibrated absolutely by comparing room temperature with liquid nitrogen temperature.
	<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>		<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>
	<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>		<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>
	The emission can be simulated by the [[TRECE]] ray tracing code.		The emission can be simulated by the [[TRECE]] ray tracing code.
	<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>		<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>
	The sampling rate is 100 kHz.		The typical sampling rate is 100 kHz.
	The signals are called 'ECE1' ... '~~ECE12~~' in the [[TJ-II:Shot_database\|TJ-II database]].		The signals are called 'ECE1' ... 'ECE16' in the [[TJ-II:Shot_database\|TJ-II database]].
	The measured ECE amplitude is proportional to the electron temperature, provided certain conditions are met.		The measured ECE amplitude is proportional to the electron temperature, provided certain conditions are met.

	== References ==		== References ==
	<references />		<references />

Admin at 07:26, 24 September 2009

2009-09-24T07:26:45Z

← Older revision		Revision as of 09:26, 24 September 2009
Line 3:		Line 3:
	<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>		<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>
	<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>		<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>
			The emission can be simulated by the [[TRECE]] ray tracing code.
	<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>		<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>
	The sampling rate is 100 kHz.		The sampling rate is 100 kHz.

Admin at 07:24, 24 September 2009

2009-09-24T07:24:33Z

← Older revision		Revision as of 09:24, 24 September 2009
Line 1:		Line 1:
	Electron cyclotron emission measurements are routinely performed in TJ-II stellarator by means of a multichannel heterodyne radiometer. The radiometer is absolutely calibrated and measures the temperature profile with high temporal resolution.		Electron cyclotron emission measurements are routinely performed in TJ-II stellarator by means of a multichannel heterodyne radiometer. The radiometer is absolutely calibrated and measures the temperature profile with high temporal resolution.
	The diagnostic provides 12 measurement channels, corresponding to 12 values of the major radius ''R''.		The diagnostic provides 12 measurement channels, corresponding to 12 values of the major radius ''R''.
	<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>		<ref>[http://link.aip.org/link/?RSINAK/72/379/1 E. de la Luna, J. Sánchez, V. Tribaldos, and T. Estrada, ''Multichannel electron cyclotron emission radiometry in TJ-II stellarator'', Rev. Sci. Instrum. '''72''', 379 (2001)]</ref>
	<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>		<ref>[http://dx.doi.org/10.1016/S0920-3796(00)00492-0 E. de la Luna et al, ''Electron cyclotron emission measurements on TJ-II stellarator plasmas'', Fusion Engineering and Design '''53''', Issues 1-4 (2001) 147-151]</ref>
	<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, Nucl. Fusion '''36''', 283 (1996)]</ref>		<ref>[http://dx.doi.org/10.1088/0029-5515/36/3/I02 V. Tribaldos and B. P. van Milligen, ''Electron cyclotron emission calculations for TJ-II stellarator'', Nucl. Fusion '''36''', 283 (1996)]</ref>
	The sampling rate is 100 kHz.		The sampling rate is 100 kHz.
	The signals are called 'ECE1' ... 'ECE12' in the [[TJ-II:Shot_database\|TJ-II database]].		The signals are called 'ECE1' ... 'ECE12' in the [[TJ-II:Shot_database\|TJ-II database]].