-
M. Moteabbed,
M. Niroula,
B. A. Raue,
L. B. Weinstein,
D. Adikaram,
J. Arrington,
W. K. Brooks,
J. Lachniet,
Dipak Rimal,
M. Ungaro, [......],
S. Tkachenko,
H. Voskanyan,
E. Voutier,
N. K. Walford,
M. H. Wood,
N. Zachariou,
L. Zana,
J. Zhang,
Z. W. Zhao,
I. Zonta
[show abstract]
[hide abstract]
ABSTRACT: The discrepancy between proton electromagnetic form factors extracted using
unpolarized and polarized scattering data is believed to be a consequence of
two-photon exchange (TPE) effects. However, the calculations of TPE corrections
have significant model dependence, and there is limited direct experimental
evidence for such corrections. We present the results of a new experimental
technique for making direct $e^\pm p$ comparisons, which has the potential to
make precise measurements over a broad range in $Q^2$ and scattering angles. We
use the Jefferson Lab electron beam and the Hall B photon tagger to generate a
clean but untagged photon beam. The photon beam impinges on a converter foil to
generate a mixed beam of electrons, positrons, and photons. A chicane is used
to separate and recombine the electron and positron beams while the photon beam
is stopped by a photon blocker. This provides a combined electron and positron
beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen
target. The large acceptance CLAS detector is used to identify and reconstruct
elastic scattering events, determining both the initial lepton energy and the
sign of the scattered lepton. The data were collected in two days with a
primary electron beam energy of only 3.3 GeV, limiting the data from this run
to smaller values of $Q^2$ and scattering angle. Nonetheless, this measurement
yields a data sample for $e^\pm p$ with statistics comparable to those of the
best previous measurements. We have shown that we can cleanly identify elastic
scattering events and correct for the difference in acceptance for electron and
positron scattering. The final ratio of positron to electron scattering:
$R=1.027\pm0.005\pm0.05$ for $<Q^2>=0.206$ GeV$^2$ and $0.830\leq \epsilon\leq
0.943$.
06/2013;
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I. Pomerantz,
Y. Ilieva,
R. Gilman,
D. W. Higinbotham,
E. Piasetzky,
S. Strauch,
K. P. Adhikari,
M. Aghasyan,
K. Allada,
M. J. Amaryan, [......],
B. Wojtsekhowski,
M. H. Wood,
X. Yan,
H. Yao,
N. Zachariou,
X. Zhan,
J. Zhang,
Z. W. Zhao,
X. Zheng,
I. Zonta
[show abstract]
[hide abstract]
ABSTRACT: We have measured cross sections for the gamma+3He->p+d reaction at photon
energies of 0.4 - 1.4 GeV and a center-of-mass angle of 90 deg. We observe
dimensional scaling above 0.7 GeV at this center-of-mass angle. This is the
first observation of dimensional scaling in the photodisintegration of a
nucleus heavier than the deuteron.
03/2013;
-
C. S. Nepali,
M. Amaryan,
K. P. Adhikari,
M. Aghasyan,
S. Anefalos Pereira,
H. Baghdasaryan,
J. Ball,
M. Battaglieri,
V. Batourine,
I. Bedlinskiy, [......],
E. Voutier,
N. K. Walford,
D. P. Watts,
L. B. Weinstein,
D. P. Weygand,
N. Zachariou,
L. Zana,
J. Zhang,
Z. W. Zhao,
I. Zonta
[show abstract]
[hide abstract]
ABSTRACT: Experimental results on the $\Sigma^+(1189)$ hyperon transverse polarization
in photoproduction on a hydrogen target using the CLAS detector at Jefferson
laboratory are presented. The $\Sigma^+(1189)$ was reconstructed in the
exclusive reaction $\gamma+p\rightarrow K^{0}_{S} + \Sigma^+(1189)$ via the
$\Sigma^{+} \to p \pi^{0}$ decay mode. The $K^{0}_S$ was reconstructed in the
invariant mass of two oppositely charged pions with the $\pi^0$ identified in
the missing mass of the detected $p\pi^+\pi^-$ final state. Experimental data
were collected in the photon energy range $E_{\gamma}$ = 1.0-3.5 GeV
($\sqrt{s}$ range 1.66-2.73 GeV). We observe a large negative polarization of
up to 95%. As the mechanism of transverse polarization of hyperons produced in
unpolarized photoproduction experiments is still not well understood, these
results will help to distinguish between different theoretical models on
hyperon production and provide valuable information for the searches of missing
baryon resonances.
02/2013;
-
P. Khetarpal,
P. Stoler,
I. G. Aznauryan,
V. Kubarovsky,
K. P. Adhikari,
D. Adikaram,
M. Aghasyan,
M. J. Amaryan,
M. D. Anderson,
S. Anefalos Pereira, [......],
H. Voskanyan,
E. Voutier,
N. K. Walford,
L. B. Weinstein,
D. P. Weygand,
M. H. Wood,
N. Zachariou,
J. Zhang,
Z. W. Zhao,
I. Zonta
[show abstract]
[hide abstract]
ABSTRACT: We report the measurement of near threshold neutral pion electroproduction
cross sections and the extraction of the associated structure functions on the
proton in the kinematic range $Q^2$ from 2 to 4.5 GeV$^2$ and $W$ from 1.08 to
1.16 GeV. These measurements allow us to access the dominant pion-nucleon
s-wave multipoles $E_{0+}$ and $S_{0+}$ in the near-threshold region. In the
light-cone sum-rule framework (LCSR), these multipoles are related to the
generalized form factors $G_1^{\pi^0 p}(Q^2)$ and $G_2^{\pi^0 p}(Q^2)$. The
data are compared to these generalized form factors and the results for
$G_1^{\pi^0 p}(Q^2)$ are found to be in good agreement with the LCSR
predictions, but the level of agreement with $G_2^{\pi^0 p}(Q^2)$ is poor.
11/2012;
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CLAS Collaboration,
I. Bedlinskiy,
V. Kubarovsky,
S. Niccolai,
P. Stoler,
K. P. Adhikari,
M. Aghasyan,
M. J. Amaryan,
M. Anghinolfi,
H. Avakian, [......],
E. Voutier,
N. K. Walford,
D. P. Watts,
L. B. Weinstein,
D. P. Weygand,
M. H. Wood,
N. Zachariou,
J. Zhang,
Z. W. Zhao,
I. Zonta
[show abstract]
[hide abstract]
ABSTRACT: Exclusive $\pi^0$ electroproduction at a beam energy of 5.75 GeV has been
measured with the Jefferson Lab CLAS spectrometer. Differential cross sections
were measured at more than 1800 kinematic values in $Q^2$, $x_B$, $t$, and
$\phi_\pi$, in the $Q^2$ range from 1.0 to 4.6 GeV$^2$,\ $-t$ up to 2 GeV$^2$,
and $x_B$ from 0.1 to 0.58. Structure functions $\sigma_T +\epsilon \sigma_L,
\sigma_{TT}$ and $\sigma_{LT}$ were extracted as functions of $t$ for each of
17 combinations of $Q^2$ and $x_B$. The data were compared directly with two
handbag-based calculations including both longitudinal and transversity GPDs.
Inclusion of only longitudinal GPDs very strongly underestimates $\sigma_T
+\epsilon \sigma_L$ and fails to account for $\sigma_{TT}$ and $\sigma_{LT}$,
while inclusion of transversity GPDs brings the calculations into substantially
better agreement with the data. There is very strong sensitivity to the
relative contributions of nucleon helicity flip and helicity non-flip
processes. The results confirm that exclusive $\pi^0$ electroproduction offers
direct experimental access to the transversity GPDs.
06/2012;
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K. Park,
M. Guidal,
R. W. Gothe,
J. M. Laget,
M. Garçon,
K. P. Adhikari,
M. Aghasyan,
M. J. Amaryan,
M. Anghinolfi,
H. Avakian, [......],
E. Voutier,
N. K. Walford,
D. P. Watts,
L. B. Weinstein,
D. P. Weygand,
M. H. Wood,
N. Zachariou,
J. Zhang,
Z. W. Zhao,
I. Zonta
[show abstract]
[hide abstract]
ABSTRACT: The exclusive electroproduction of $\pi^+$ above the resonance region was
studied using the $\rm{CEBAF}$ Large Acceptance Spectrometer ($\rm{CLAS}$) at
Jefferson Laboratory by scattering a 6 GeV continuous electron beam off a
hydrogen target. The large acceptance and good resolution of $\rm{CLAS}$,
together with the high luminosity, allowed us to measure the cross section for
the $\gamma^* p \to n \pi^+$ process in 140 ($Q^2$, $x_B$, $t$) bins:
$0.16<x_B<0.58$, 1.6 GeV$^2<$$Q^2$$<4.5$ GeV$^2$ and 0.1 GeV$^2<$$-t$$<5.3$
GeV$^2$. For most bins, the statistical accuracy is on the order of a few
percent. Differential cross sections are compared to two theoretical models,
based either on hadronic (Regge phenomenology) or on partonic (handbag diagram)
degrees of freedom. Both can describe the gross features of the data reasonably
well, but differ strongly in their ingredients. If the handbag approach can be
validated in this kinematical region, our data contain the interesting
potential to experimentally access transversity Generalized Parton
Distributions.
06/2012;
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H. Egiyan,
J. Langheinrich,
R. W. Gothe,
L. Graham,
M. Holtrop,
H. Lu,
P. Mattione,
G. Mutchler,
K. Park,
E. S. Smith, [......],
D. J. Tedeschi,
M. Ungaro,
E. Voutier,
D. P. Watts,
L. B. Weinstein,
D. P. Weygand,
M. H. Wood,
N. Zachariou,
L. Zana,
B. Zhao
[show abstract]
[hide abstract]
ABSTRACT: We searched for the Φ−−(1860) pentaquark in the photoproduction process off the deuteron in the Ξ−π−-decay channel using CLAS. The invariant-mass spectrum of the Ξ−π− system does not indicate any statistically significant enhancement near the reported mass M=1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90%-confidence-level upper limit of 0.7 nb for the photoproduction cross section of Φ−−(1860) with a consecutive decay into Ξ−π− in the photon-energy range 4.5 GeV<Eγ<5.5 GeV.
Phys. Rev. C. 01/2012; 85(1).
-
L. El Fassi,
L. Zana,
K. Hafidi,
M. Holtrop,
B. Mustapha,
W. K. Brooks,
H. Hakobyan,
X. Zheng,
K. P. Adhikari,
D. Adikaram, [......],
M. F. Vineyard,
H. Voskanyan,
E. Voutier,
D. Watts,
L. B. Weinstein,
D. P. Weygand,
M. H. Wood,
N. Zachariou,
B. Zhao,
Z. W. Zhao
[show abstract]
[hide abstract]
ABSTRACT: We have measured the nuclear transparency of the incoherent diffractive
$A(e,e'\rho^0)$ process in $^{12}$C and $^{56}$Fe targets relative to $^2$H
using a 5 GeV electron beam. The nuclear transparency, the ratio of the
produced $\rho^0$'s on a nucleus relative to deuterium, which is sensitive to
$\rho A$ interaction, was studied as function of the coherence length ($l_c$),
a lifetime of the hadronic fluctuation of the virtual photon, and the
four-momentum transfer squared ($Q^2$). While the transparency for both
$^{12}$C and $^{56}$Fe showed no $l_c$ dependence, a significant $Q^2$
dependence was measured, which is consistent with calculations that included
the color transparency effects.
01/2012;
-
M. Aghasyan,
H Avakian,
P Rossi,
E De Sanctis,
D. Hasch,
M Mirazita,
D. Adikaram,
M J Amaryan,
M Anghinolfi,
H Baghdasaryan, [......],
H. Voskanyan,
E. Voutier,
D. Watts,
L B Weinstein,
D P Weygand,
M H Wood,
L Zana,
J Zhang,
B Zhao,
Z W Zhao
[show abstract]
[hide abstract]
ABSTRACT: We present studies of single-spin asymmetries for neutral pion
electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV
polarized electrons from an unpolarized hydrogen target, using the CEBAF Large
Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator
Facility. A substantial $\sin \phi_h$ amplitude has been measured in the
distribution of the cross section asymmetry as a function of the azimuthal
angle $\phi_h$ of the produced neutral pion. The dependence of this amplitude
on Bjorken $x$ and on the pion transverse momentum is extracted with
significantly higher precision than previous data and is compared to model
calculations.
06/2011;
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R. Nasseripour,
B.L. Berman,
K.P. Adhikari,
D. Adikaram,
M. Anghinolfi,
J. Ball,
M. Battaglieri,
V. Batourine,
I. Bedlinskiy,
A.S. Biselli, [......],
M. Ungaro,
B. Vernarsky,
M.F. Vineyard,
E. Voutier,
D.P. Watts,
L.B. Weinstein,
D.P. Weygand,
M.H. Wood,
B. Zhao,
Z.W. Zhao
[show abstract]
[hide abstract]
ABSTRACT: We have measured the differential cross section for the γ3He→π+t reaction. This reaction was studied using the Continuous Electron Beam Accelerator Facility (CEBAF) Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B bremsstrahlung tagging system in the energy range from 0.50 to 1.55 GeV were incident on a cryogenic liquid 3He target. The differential cross sections for the γ3He→π+t reaction were measured as a function of photon-beam energy and pion-scattering angle. Theoretical predictions to date cannot explain the large cross sections except at backward angles, showing that additional components must be added to the model.
Phys. Rev. C. 03/2011; 83(3).
-
X Qian,
W Chen,
H Gao,
K Hicks,
K Kramer,
J M Laget,
T Mibe,
Y. Qiang,
S Stepanyan,
D J Tedeschi, [......],
M F Vineyard,
E. Voutier,
L B Weinstein,
D P Weygand,
M H Wood,
N. Zachariou,
L Zana,
J Zhang,
B Zhao,
Z W Zhao
[show abstract]
[hide abstract]
ABSTRACT: We report the first measurement of the differential cross section on
$\phi$-meson photoproduction from deuterium near the production threshold for a
proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson
Lab. The measurement was carried out by a triple coincidence detection of a
proton, $K^+$ and $K^-$ near the theoretical production threshold of 1.57 GeV.
The extracted differential cross sections $\frac{d\sigma}{dt}$ for the initial
photon energy from 1.65-1.75 GeV are consistent with predictions based on a
quasifree mechanism. This experiment establishes a baseline for a future
experimental search for an exotic $\phi$-N bound state from heavier nuclear
targets utilizing subthreshold/near-threshold production of $\phi$ mesons.
11/2010;
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H Baghdasaryan,
L B Weinstein,
J M Laget,
K P Adhikari,
M Aghasyan,
M Amarian,
M Anghinolfi,
H Avakian,
J Ball,
M Battaglieri, [......], C E Taylor,
D J Tedeschi,
M Ungaro,
M F Vineyard,
E Voutier,
D P Watts,
D P Weygand,
M H Wood,
B Zhao,
Z W Zhao
[show abstract]
[hide abstract]
ABSTRACT: We have measured the 3He(e,e' pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs by using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum p(tot). For pair relative momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low p(tot) and rises to approximately 0.5 at large p(tot). This shows the dominance of tensor over central correlations at this relative momentum.
Physical Review Letters 11/2010; 105(22):222501. · 7.37 Impact Factor
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M H Wood,
R Nasseripour,
M Paolone,
C Djalali,
D P Weygand,
K P Adhikari,
M Anghinolfi,
J Ball,
M Battaglieri,
V Batourine, [......],
S Tkachenko,
M Ungaro,
B Vernarsky,
M F Vineyard,
E Voutier,
D P Watts,
L B Weinstein,
J Zhang,
B Zhao,
Z W Zhao
[show abstract]
[hide abstract]
ABSTRACT: Because of their long lifetimes, the ω and ϕ mesons are the ideal candidates for the study of possible modifications of the in-medium meson-nucleon interaction through their absorption inside the nucleus. During the E01-112 experiment at the Thomas Jefferson National Accelerator Facility, the mesons were photoproduced from 2H, C, Ti, Fe, and Pb targets. This Letter reports the first measurement of the ratio of nuclear transparencies for the e+e- channel. The ratios indicate larger in-medium widths compared with what have been reported in other reaction channels. The absorption of the ω meson is stronger than that reported by the CBELSA-TAPS experiment and cannot be explained by recent theoretical models.
Physical Review Letters 09/2010; 105(11):112301. · 7.37 Impact Factor
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H Baghdasaryan,
L B Weinstein,
J M Laget,
K. P. Adhikari,
M. Aghasyan,
M Amarian,
M Anghinolfi,
H Avakian,
J Ball,
M Battaglieri, [......], C. E. Taylor,
D J Tedeschi,
M Ungaro,
M F Vineyard,
E. Voutier,
D. P. Watts,
D P Weygand,
M H Wood,
B Zhao,
Z W Zhao
[show abstract]
[hide abstract]
ABSTRACT: We have measured the 3He(e,e'pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum, $p_{tot}$. For pair relative momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low $p_{tot}$ and rises to approximately 0.5 at large $p_{tot}$. This shows the dominance of tensor over central correlations at this relative momentum. Comment: 4 pages, 4 figures, submitted to PRL
08/2010;
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B. Dey,
C. A. Meyer,
M. Bellis,
M. E. McCracken,
M. Williams,
K. P. Adhikari,
M. Aghasyan,
M. Anghinolfi,
J. Ball,
M. Battaglieri, [......],
D. P. Watts,
B. Vernarsky,
M. F. Vineyard,
E. Voutier,
L. B. Weinstein,
M. H. Wood,
A. Yegneswaran,
J. Zhang,
B. Zhao,
Z. W. Zhao
[show abstract]
[hide abstract]
ABSTRACT: High-statistics measurements of differential cross sections and recoil polarizations for the reaction γp→K+Σ0 have been obtained using the CLAS detector at Jefferson Lab. We cover center-of-mass energies (√s) from 1.69 to 2.84 GeV, with an extensive coverage in the K+ production angle. Independent measurements were made using the K+pπ-(γ) and K+p(π-,γ) final-state topologies, and were found to exhibit good agreement. Our differential cross sections show good agreement with earlier CLAS, SAPHIR, and LEPS results, while offering better statistical precision and a 300-MeV increase in √s coverage. Above √s≈2.5 GeV, t- and u-channel Regge scaling behavior can be seen at forward and backward angles, respectively. Our recoil polarization (PΣ) measurements represent a substantial increase in kinematic coverage and enhanced precision over previous world data. At forward angles, we find that PΣ is of the same order of magnitude but opposite sign as PΛ, in agreement with the static SU(6) quark model prediction of PΣ≈-PΛ. This expectation is violated in some mid- and backward-angle kinematic regimes, where PΣ and PΛ are of similar magnitudes but also have the same signs. In conjunction with several other meson photoproduction results recently published by CLAS, the present data will help constrain the partial-wave analyses being performed to search for missing baryon resonances.
Phys. Rev. C. 08/2010; 82(2).
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[show abstract]
[hide abstract]
ABSTRACT: An ultra-high-speed camera utilizing an acousto-optic device for deflecting light rays is described. The system employs a
pulsed-ruby-laser light source used in conjunction with a Cranz-Schardin-type camera thus utilizing the best features of both
systems for recording a sequence of photographs.
The system has been demonstrated at framing rates of up to 200,000 frames/s and has the potential for considerably faster
operation. It features the capability of producing a sequence of dynamic photographs in which the time between succesive exposures
can be independently varied. Thus, the frequency at which photographs are obtained can be increased during the times of greatest
interest. Experimental results demonstrating these features are given.
Experimental Mechanics 01/1975; 15(8):289-294. · 1.52 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: A specimen illuminated by coherent light is imaged by a camera through a shearing mechanism so that the speckle from one point on the surface can be made to interfere with the speckle from a neighboring point. The resultant speckle pattern is recorded. By mechanically interfering the recorded speckle pattern corresponding to deformed and undeformed states of the specimen, respectively, using double-exposure technique, a speckle-moir-fringe pattern is generated. These fringes which depict derivatives of deflections of the specimen are made visible by spatial-filtering technique. Speckle-moir fringes can also be obtained in real time. This method is a new interferometry and will be referred to as speckle-shearing interferometry.Speckle-shearing interferometry has the same function as Ligtenberg's technique. However, it does not have the sometimes inconvenient requirement of Ligtenberg's technique that the surface of the specimen must be of mirror quality. The new technique will be particularly useful in studies of flexural deformation such as flexed beams and plates.Although speckle-shearing interferometry is an interferometric method, it overcomes several of the limitations associated with holographic and speckle interferometries, namely: (1) the setup is simple and does not need laborious alignments of optical components, (2) it does not require stringent mechanical and ambient stabilities, (3) coherent requirement of light is greatly relaxed, and (4) the sensitivity is reduced that somehow fills the gap in sensitivity between moir techniques and holographic or speckle interferometry.
Experimental Mechanics 06/1974; 14(7):281-285. · 1.52 Impact Factor
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X. Qian,
W. Chen,
H. Gao,
K. Hicks,
K. Kramer,
J.M. Laget,
T. Mibe,
Y. Qiang,
S. Stepanyan,
D.J. Tedeschi, [......],
M.F. Vineyard,
E. Voutier,
L.B. Weinstein,
D.P. Weygand,
M.H. Wood,
N. Zachariou,
L. Zana,
J. Zhang,
B. Zhao,
Z.W. Zhao
[show abstract]
[hide abstract]
ABSTRACT: We report the first, kinematically-complete measurement of the differential cross section of ϕ-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, K+ and K− near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections for the initial photon energy range of 1.65–1.75 GeV are consistent with predictions based on a quasifree mechanism. Our finding is different from recent LEPS results on ϕ-meson photoproduction from deuterium in a similar incident photon energy range, but in a different momentum transfer region.
Physics Letters B.
-
R Nasseripour,
B L Berman,
K. P. Adhikari,
D. Adikaram,
M Anghinolfi,
J Ball,
M Battaglieri,
V Batourine,
I Bedlinskiy,
A S Biselli, [......],
M Ungaro,
B . Vernarsky,
M F Vineyard,
E. Voutier,
D. P. Watts,
L B Weinstein,
D P Weygand,
M H Wood,
B Zhao,
Z W Zhao
[show abstract]
[hide abstract]
ABSTRACT: We have measured the differential cross section for the $\gamma$$^3$He$\rightarrow \pi^+ t$ reaction. This reaction was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B bremsstrahlung tagging system in the energy range from 0.50 to 1.55 GeV were incident on a cryogenic liquid $^3$He target. The differential cross sections for the $\gamma$$^3$He$\rightarrow \pi^+ t$ reaction were measured as a function of photon-beam energy and pion-scattering angle. Theoretical predictions to date cannot explain the large cross sections except at backward angles, showing that additional components must be added to the model.
Physical Review C.
-
[show abstract]
[hide abstract]
ABSTRACT: A glow curve analyzer (GCA) spreadsheet has been developed using Microsoft®Excel™ to perform glow curve analysis on thermoluminescent dosimeter (TLD) data from a personnel dosimetry system. The TLD data come from cards with four LiF:Mg,Ti chips that have been annealed and therefore have a simple glow peak structure. GCA removes spikes in the glow curve data, and then smoothes it. After select start and end points for the glow peak, it fits a Boltzmann function to represent the glow curve signal background under the glow peak. The Boltzmann function is subtracted and two Weibull curves are fit to the remaining net signal between the start and end points. The first Weibull curve is fit to peak 5, and the second one to any small remaining contribution from peaks 3 and 4 or from contaminants. The sum of the two Weibull curves is the glow curve signal result. GCA provides rapid review and correction of all glow curves, improving the quality of the results and reducing the time required for complete processing of official dose results.
Radiation Measurements.
