2018 NSF Proposal - Revision history

Foretony at 17:55, 27 November 2019

2019-11-27T17:55:27Z

Foretony at 03:48, 19 November 2018

2018-11-19T03:48:22Z

Foretony: /* CLAS Polarized Structure Function */

2018-11-19T01:42:37Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-19T01:42:01Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-08T17:14:13Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-08T17:10:09Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-05T06:15:30Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-05T05:39:11Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-05T05:25:43Z

CLAS Polarized Structure Function

Foretony: /* CLAS Polarized Structure Function */

2018-11-05T02:58:40Z

CLAS Polarized Structure Function

← Older revision		Revision as of 17:55, 27 November 2019
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−	~~A1p&SIDIS~~	+

	RFP Due date Dec. 11		RFP Due date Dec. 11

← Older revision		Revision as of 03:48, 19 November 2018
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	[[NSF]]		[[NSF]]
		+
		+
		+	A1p&SIDIS

	RFP Due date Dec. 11		RFP Due date Dec. 11

← Older revision		Revision as of 01:42, 19 November 2018
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−	[[File:PolTarg_2018.png \| 200 px]][[File:DeltaDoverD_2018.png \| 200 px]][[File:~~DeltaDoverDPrecDrop_2018~~.png \| 200 px]]	+	[[File:PolTarg_2018.png \| 200 px]][[File:DeltaDoverD_2018.png \| 200 px]][[File:DeltaDoverDPrecIncrease_2018.png \| 200 px]]

	The pQcd prediction is shown as a solid filled circle while the open circle represents the results from ref ~\cite{ISgur1999}, ~\cite{Roberts2013}. The red dash-dot line is a dyson-swinger euation calculation from reference ~\cite{Cloet2005}. The blue dashed line is an early parameterization of the world data from ~\cite{Leader1998}. The blue line and blue dash-dot curve are parametrization fits to the world data from reference ~\cite{Avakian2007} with and without the pQCD constraint when non zero angular momentum states are included. The solid red and dashed red curves are a more recent parameterization of the world data set from reference ~\cite{JAM15} without and with the pQCD prediction respectively.		The pQcd prediction is shown as a solid filled circle while the open circle represents the results from ref ~\cite{ISgur1999}, ~\cite{Roberts2013}. The red dash-dot line is a dyson-swinger euation calculation from reference ~\cite{Cloet2005}. The blue dashed line is an early parameterization of the world data from ~\cite{Leader1998}. The blue line and blue dash-dot curve are parametrization fits to the world data from reference ~\cite{Avakian2007} with and without the pQCD constraint when non zero angular momentum states are included. The solid red and dashed red curves are a more recent parameterization of the world data set from reference ~\cite{JAM15} without and with the pQCD prediction respectively.

← Older revision		Revision as of 01:42, 19 November 2018
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−	[[File:PolTarg_2018.png \| 200 px]][[File:DeltaDoverD_2018.png \| 200 px]]	+	[[File:PolTarg_2018.png \| 200 px]][[File:DeltaDoverD_2018.png \| 200 px]][[File:DeltaDoverDPrecDrop_2018.png \| 200 px]]

	The pQcd prediction is shown as a solid filled circle while the open circle represents the results from ref ~\cite{ISgur1999}, ~\cite{Roberts2013}. The red dash-dot line is a dyson-swinger euation calculation from reference ~\cite{Cloet2005}. The blue dashed line is an early parameterization of the world data from ~\cite{Leader1998}. The blue line and blue dash-dot curve are parametrization fits to the world data from reference ~\cite{Avakian2007} with and without the pQCD constraint when non zero angular momentum states are included. The solid red and dashed red curves are a more recent parameterization of the world data set from reference ~\cite{JAM15} without and with the pQCD prediction respectively.		The pQcd prediction is shown as a solid filled circle while the open circle represents the results from ref ~\cite{ISgur1999}, ~\cite{Roberts2013}. The red dash-dot line is a dyson-swinger euation calculation from reference ~\cite{Cloet2005}. The blue dashed line is an early parameterization of the world data from ~\cite{Leader1998}. The blue line and blue dash-dot curve are parametrization fits to the world data from reference ~\cite{Avakian2007} with and without the pQCD constraint when non zero angular momentum states are included. The solid red and dashed red curves are a more recent parameterization of the world data set from reference ~\cite{JAM15} without and with the pQCD prediction respectively.

@@ Line 33: / Line 33: @@
 Fig.~\ref{fig:DeltaDoverD} show the data for $\Delta d(x)/d(x)$ from HERMES and JLab measured in a kinematic range where the down quark carried a fraction of the nucleon's momentum ($x_B$) that was less than 0.6.  The HERMES measurement used both Inclusive and Semi-Inclusive Deep Inelastic (SIDIS) scattering while the JLab measurements used fits to inclusive electron scattering measurements of polarized structure functions ($g$) and unpolarized structure function ($F$) of the proton, deuteron, and He-3 as well as the ratio of up and down quark distributions from proton and deuteron data.
-While predictions of $\Deltad(x)/d(x)$ using the constituent quark model (CQM)~\site{Isgur1999} ~\cite{Cloet20015}, and the Dyson-Swinger equations~\cite{Roberts2013} predicts  $\frac{\Delta d}{d}$ remains negative as $x_B$ approaches unity, perturbative quantum chromodynamics (pQCD) predicts that it will become positive, as shown in a Fig.~\ref{fig:DeltaDoverD}.  This large difference between the two predictions now relies on experiment to resolve the disagreement.  The current measurements in Fig.~\ref{fig:DeltaDoverD} have not shown a clear indication of this predicted sign change as there is a sparsity of data beyond $x_B > 0.5$. There is a clear need to perform measurements above $x_B$ of 0.5 in order to evaluate the veracity of the pQCD and CQM predictions.
+While predictions of $\Delta d(x)/d(x)$ using the constituent quark model (CQM)~\cite{Isgur1999} ~\cite{Cloet20015}, and the Dyson-Swinger equations~\cite{Roberts2013} predicts  $\frac{\Delta d}{d}$ remains negative as $x_B$ approaches unity, perturbative quantum chromodynamics (pQCD) predicts that it will become positive, as shown in a Fig.~\ref{fig:DeltaDoverD}.  This large difference between the two predictions now relies on experiment to resolve the disagreement.  The current measurements in Fig.~\ref{fig:DeltaDoverD} have not shown a clear indication of this predicted sign change as there is a sparsity of data beyond $x_B > 0.5$. There is a clear need to perform measurements above $x_B$ of 0.5 in order to evaluate the veracity of the pQCD and CQM predictions.
 One of the goals of experiment PR12-06-109, in JLab's Hall B,  is to measure $\frac{\Delta d}{d}$ above $x_B$ of 0.5.  Fig.~\ref{fig:DeltaDoverD} illustrates the precision that may be achieved using the CLAS12 apparatus.  In particular, the measurement at $x_B$ of 0.7 should distinguish between the two prediction at the 2$\sigma$ level.

← Older revision		Revision as of 17:10, 8 November 2018
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	Existing CLAS data from 6 GeV have already made an impact on these fits. The expected data from the proposed experiment at 11~GeV will further reduce the uncertainties of these distributions as seen inf Fige.~\ref{fig:JAM15} from the JAM collaboration~\cite{Jimeniez2014_JAM15}		Existing CLAS data from 6 GeV have already made an impact on these fits. The expected data from the proposed experiment at 11~GeV will further reduce the uncertainties of these distributions as seen inf Fige.~\ref{fig:JAM15} from the JAM collaboration~\cite{Jimeniez2014_JAM15}

−	JLab's energy upgrade to 12 GeV will facilitate the above measurements. As a service to Hall~B and to satisfy the needs of experiment E12-06-109, co-PI Forest was responsible for the construction of five drift chambers. These drift chambers are approximately 6 feet high and contain over 5,000 wires. ISU constructed and tested these drift chambers that are now in operation in Hall B. The CEBAF Large Acceptance Spectrometer in Hall~B has just began twelve GeV era research program. Preparations for the next phase of experiment E12-06-109, the experiment readiness review, is scheduled for March of 2018 and the experiment is currently schedule to run in the Fall of 2020. As part of this review Co-PI Forest developed a geometrical description of the proposed dual polarized target system and presented that design at the 5th Joint Meeting of the APS Division of Nuclear Physics and the Physical Society of Japan on October 27, 2018.	+	JLab's energy upgrade to 12 GeV will facilitate the above measurements. As a service to Hall~B and to satisfy the needs of experiment E12-06-109, co-PI Forest was responsible for the construction of five drift chambers. These drift chambers are approximately 6 feet high and contain over 5,000 wires. ISU constructed and tested these drift chambers that are now in operation in Hall B. The CEBAF Large Acceptance Spectrometer in Hall~B has just began its twelve GeV era research program. Preparations for the next phase of experiment E12-06-109, the experiment readiness review, is scheduled for March of 2018 and the experiment is currently schedule to run in the Fall of 2020. As part of this review Co-PI Forest developed a geometrical description of the proposed dual polarized target system and presented that design at the 5th Joint Meeting of the APS Division of Nuclear Physics and the Physical Society of Japan on October 27, 2018.

@@ Line 25: / Line 25: @@
 ==Introduction==
 ==CLAS Polarized Structure Function==
-Nucleon spin structure functions have been measured using deep inelastic lepton scattering (DIS) for over 20 years since the first experiments at the SLAC National Accelerator Laboratory. Interest increased substantially in the 1980s when the EMC collaboration reported that quarks make a small contribution to the overall spin of the proton. This ``spin puzzle'' led to a vigorous theoretical and experimental effort that continues to this day.
+Nucleon spin structure functions have been measured using deep inelastic lepton scattering (DIS) for over 30 years since the first experiments at the SLAC National Accelerator Laboratory. Interest increased substantially in the 1980s when the EMC collaboration reported that quarks make a small contribution to the overall spin of the proton. This ``spin puzzle'' led to a vigorous theoretical and experimental effort that continues to this day.
 Although having a large world data set in a kinematic range that is sensitive to both valence quarks and quark-antiquark pairs, there is a limited amount of data in a region dominated by valence quarks.
 As a result, research on the quark contribution to a nucleon's structure continues unabated.

← Older revision		Revision as of 05:39, 5 November 2018
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	Existing CLAS data from 6 GeV have already made an impact on these fits. The expected data from the proposed experiment at 11~GeV will further reduce the uncertainties of these distributions as seen inf Fige.~\ref{fig:JAM15} from the JAM collaboration~\cite{Jimeniez2014_JAM15}		Existing CLAS data from 6 GeV have already made an impact on these fits. The expected data from the proposed experiment at 11~GeV will further reduce the uncertainties of these distributions as seen inf Fige.~\ref{fig:JAM15} from the JAM collaboration~\cite{Jimeniez2014_JAM15}

−	JLab's energy upgrade to 12 GeV will facilitate the above measurements.	+	JLab's energy upgrade to 12 GeV will facilitate the above measurements. As a service to Hall~B and to satisfy the needs of experiment E12-06-109, co-PI Forest was responsible for the construction of five drift chambers. These drift chambers are approximately 6 feet high and contain over 5,000 wires. ISU constructed and tested these drift chambers that are now in operation in Hall B. The CEBAF Large Acceptance Spectrometer in Hall~B has just began twelve GeV era research program. Preparations for the next phase of experiment E12-06-109, the experiment readiness review, is scheduled for March of 2018 and the experiment is currently schedule to run in the Fall of 2020. As part of this review Co-PI Forest developed a geometrical description of the proposed dual polarized target system and presented that design at the 5th Joint Meeting of the APS Division of Nuclear Physics and the Physical Society of Japan on October 27, 2018.
−	~~The CEBAF Large Acceptance Spectrometer in Hall~B has just completed its first series of experiments~~ . As a service to Hall~B and to satisfy the needs of experiment E12-06-109, co-PI Forest was responsible for the construction of five drift chambers. These drift chambers are approximately 6 feet high and contain over 5,000 wires. ISU constructed and tested these drift chambers that are now in operation in Hall B. Preparations for the next phase of experiment E12-06-109, the experiment readiness review, is ~~taking place now~~. As part of this ~~revie~~ Co-PI Forest developed a geometrical description of the proposed dual polarized target system as presented that design at the ~~latest NDP meeting~~.

@@ Line 29: / Line 29: @@
 As a result, research on the quark contribution to a nucleon's structure continues unabated.
-The 2015 NSAC long range plan identified  measurements of the fractional polarization of down quarks in the nucleon ($\frac{\Delta d}{d}$) as providing "important
+The 2015 NSAC Long Range Plan for Nuclear Science identified  measurements of the fractional polarization of down quarks in the nucleon ($\frac{\Delta d}{d}$) as providing "important
 insight on nucleon structure."
 Fig.~\ref{fig:DeltaDoverD} show the data for $\Delta d(x)/d(x)$ from HERMES and JLab measured in a kinematic range where the down quark carried a fraction of the nucleon's momentum ($x_B$) that was less than 0.6.  The HERMES measurement used both Inclusive and Semi-Inclusive Deep Inelastic (SIDIS) scattering while the JLab measurements used fits to inclusive electron scattering measurements of polarized structure functions ($g$) and unpolarized structure function ($F$) of the proton, deuteron, and He-3 as well as the ratio of up and down quark distributions from proton and deuteron data.

@@ Line 33: / Line 33: @@
 Fig.~\ref{fig:DeltaDoverD} show the data for $\Delta d(x)/d(x)$ from HERMES and JLab measured in a kinematic range where the down quark carried a fraction of the nucleon's momentum ($x_B$) that was less than 0.6.  The HERMES measurement used both Inclusive and Semi-Inclusive Deep Inelastic (SIDIS) scattering while the JLab measurements used fits to inclusive electron scattering measurements of polarized structure functions ($g$) and unpolarized structure function ($F$) of the proton, deuteron, and He-3 as well as the ratio of up and down quark distributions from proton and deuteron data.
-While the constituent quark model (CQM) predicts that  $\frac{\Delta d}{d}$ remains negative as $x_B$ approaches unity, perturbative quantum chromodynamics (pQCD) predicts that it will become positive, as shown in a Fig.~\ref{fig:DeltaDoverD}.  This large difference between the two predictions now relies on experiment to resolve the disagreement.  The current measurements shown in Fig.~\ref{fig:DeltaDoverD} have not shown a clear indication of this predicted sign change as there is a sparsity of data beyond $x_B > 0.5$.  There is a clear need to perform measurements above $x_B$ of 0.5 in order to evaluate the veracity of the pQCD and CQM predictions.
+While predictions of $\Deltad(x)/d(x)$ using the constituent quark model (CQM)~\site{Isgur1999} ~\cite{Cloet20015}, and the Dyson-Swinger equations~\cite{Roberts2013} predicts  $\frac{\Delta d}{d}$ remains negative as $x_B$ approaches unity, perturbative quantum chromodynamics (pQCD) predicts that it will become positive, as shown in a Fig.~\ref{fig:DeltaDoverD}.  This large difference between the two predictions now relies on experiment to resolve the disagreement.  The current measurements in Fig.~\ref{fig:DeltaDoverD} have not shown a clear indication of this predicted sign change as there is a sparsity of data beyond $x_B > 0.5$. There is a clear need to perform measurements above $x_B$ of 0.5 in order to evaluate the veracity of the pQCD and CQM predictions.
 One of the goals of experiment PR12-06-109, in JLab's Hall B,  is to measure $\frac{\Delta d}{d}$ above $x_B$ of 0.5.  Fig.~\ref{fig:DeltaDoverD} illustrates the precision that may be achieved using the CLAS12 apparatus.  In particular, the measurement at $x_B$ of 0.7 should distinguish between the two prediction at the 2$\sigma$ level.
 The comprehensive data set to be collected by experiment PR12-06-109 (co-PI Forest) will also contribute substantially to our knowledge of polarized parton distribution functions for all quark flavors and even the polarized gluon distribution $\Delta g$, which is also being pursued at Relativistic Heavy Ion Collider (RHIC).
 Through Next-to-Leading Order (NLO) analysis of the world data on inclusive DIS (using the DGLAP evolution equations), one can constrain these distribution functions and their integrals.
-Existing CLAS data from 6 GeV have already made an impact on these fits. The expected data from the proposed experiment at 11~GeV will further reduce the uncertainties of these distributions.
+Existing CLAS data from 6 GeV have already made an impact on these fits. The expected data from the proposed experiment at 11~GeV will further reduce the uncertainties of these distributions as seen inf Fige.~\ref{fig:JAM15} from the JAM collaboration~\cite{Jimeniez2014_JAM15}
 JLab's energy upgrade to 12 GeV will facilitate the above measurements.
-The CEBAF Large Acceptance Spectrometer in Hall~B is currently undergoing an upgrade of its detector systems to accommodate the increased energy as well.  As a service to Hall~B and to satisfy the needs of experiment PR12-06-109, co-PI Forest has become responsible for the construction of five drift chambers.  These drift chambers are approximately 6 feet high and contain over 5,000 wires.  ISU has successfully constructed and tested one chamber with two more nearing completion.  The ISU clean room being used for this work is shown in Fig.~\ref{delqJLab}.
+The CEBAF Large Acceptance Spectrometer in Hall~B has just completed its first series of experiments .  As a service to Hall~B and to satisfy the needs of experiment E12-06-109, co-PI Forest was responsible for the construction of five drift chambers.  These drift chambers are approximately 6 feet high and contain over 5,000 wires.  ISU constructed and tested these drift chambers that are now in operation in Hall B.  Preparations for the next phase of experiment E12-06-109, the experiment readiness review, is taking place now.  As part of this revie Co-PI Forest developed a geometrical description of the proposed dual polarized target system as presented that design at the latest NDP meeting.