PDA

View Full Version : Measurements of GEn/GMn from the ^2H(vec{e},e'vec{n})^1H Reaction to Q^2=1.45 (GeV/c)


mr_G
01-03-2006, 09:23:35
:sleep:

JM^3
01-03-2006, 09:25:01
well, talk about bridges...

JM

mr_G
01-03-2006, 09:30:21
I am way way way too dumb for Measurements of GEn/GMn from the ^2H(vec{e},e'vec{n})^1H Reaction to Q^2=1.45 (GeV/c) Jon.

bless god bless bless bless that dude for that.

JM^3
01-03-2006, 09:32:59
well, I am waiting to see if my timing calibration program works

I maybe should run it on less data, for testing, but I keep hoping that it will work the first time

Asher or SP would hate it, it is very much thrown together...

JM

Fistandantilus
01-03-2006, 09:34:18
That explains why MrG's bridge is also commonly known as crumble bridge from the locals.

Tizzy
01-03-2006, 09:36:34
Originally posted by mr_G
I am way way way too dumb for Measurements of GEn/GMn from the ^2H(vec{e},e'vec{n})^1H Reaction to Q^2=1.45 (GeV/c) Jon.

bless god bless bless bless that dude for that.

I have already learnt something today so that means I don't have to try and understand this.

Phew.

MoSe
01-03-2006, 09:40:16
I feel instead a sheer excitement in reading about it, even if I don't understand at all and don't even try

thanks J!

mr_G
01-03-2006, 09:56:20
4
TABLE II: Results for g = Gn
E/Gn
M and Gn
E.
hQ2i [(GeV/c)2] g = Gn
E/Gn
M Gn
M/オnGD [20] Gn
E
0.447 −0.0761 ア 0.0083 ア 0.0021 1.003 ア 0.006 0.0550 ア 0.0060 ア 0.0016
1.132 −0.131 ア 0.010 ア 0.003 1.057 ア 0.017 0.0394 ア 0.0029 ア 0.0012
1.450 −0.190 ア 0.016 ア 0.004 1.044 ア 0.024 0.0411 ア 0.0035 ア 0.0013
0
0.02
0.04
0.06
0.08
0.1
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
MIT-Bates: d(e5,e地5) [1]
JLab E93-026: d5(e5,e地) [7]
Mainz A1: 3H5
e(e5,e地) [4]
Mainz A3: d(e5,e地5) [2]
Mainz A3: 3H5
e(e5,e地) [5]
NIKHEF: d5(e5,e地) [6]
Schiavilla & Sick [9]
This Work
Q2 [(GeV/c)2]
GE n
FIG. 3: The current world data on Gn
E versus Q2 extracted
from polarization measurements and an analysis of
the deuteron quadrupole form factor [1, 2, 4, 5, 6, 7, 9]. The
Galster parameterization [8] is the dashed line, and our twoparameter
Galster fit (see text) is the solid line.
such that the net e ect upon g is small at hQ2i = 0.45
(GeV/c)2 and negligible at the two higher Q2 points.
The values of g and Gn
E that we report are listed in
Table II. To determine our values for Gn
E, we used the
best-fit values for Gn
M (listed in Table II) obtained using
the methods described in [20]. The new fit omits the data
of [21, 22] and includes the recent data of Xu et al. [23].
The results are similar to those obtained by Friedrich
and Walcher [24] using a parameterization designed to
investigate the role of the pion cloud. The fit is also
similar to that of Kubon et al. [25] within their range of
Q2, but extends to larger Q2. For g and Gn
E, the first set
of errors is statistical, and the second set is systematic.
The quoted systematic uncertainties for g include a 2%
uncertainty that results when a di erent selection of runs
is used for the time calibration. To obtain the systematic
uncertainties for Gn
E, the relative uncertainties in Gn
M
were added quadratically to the systematic uncertainties
listed in Table I and the 2% time calibration uncertainty.
Our values for Gn
E are plotted in Fig. 3 together with
the current world data on Gn
E [1, 2, 4, 5, 6, 7, 9] extracted
from polarization measurements and an analysis
of the deuteron quadrupole form factor. We fitted these
data and the Gn
E slope at the origin as measured via lowenergy
neutron scattering from electrons in heavy atoms
[17] to a Galster parameterization: Gn
E = −aオnτGD/(1+
bτ), where τ = Q2/4M2
n, GD = (1 + Q2/2)−2, and
2 = 0.71 (GeV/c)2. Our best-fit parameters are a =
0.888 ア 0.023 and b = 3.21 ア 0.33.
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4 5 6
JLab Hall A: p(e5,e恥5) [27,29]
Mainz A1: p(e5,e恥5) [28]
MIT-Bates: p(e5,e恥5) [26]
mpGE p
/ GM p
0
0.1
0.2
0.3
0.4
0 0.5 1 1.5 2 2.5 3 3.5
Light-Cone Diquark: [31]
Light-Front OGE: [34]
Light-Front CBM: [33]
VMD + pQCD: [35]
PFSA GBE: [32]
Chiral Soliton: [30]
Q2 [(GeV/c)2]
mnGE n
/ GM n
FIG. 4: Predictions of selected models (see text) for
オpGp
E/Gp
M and オnGn
E/Gn
M compared with proton [26, 27, 28,
29] and neutron [1, 2, 4, 5, 6, 7] data. The neutron data
symbols are the same as in Fig. 3.
Polarization measurements of Gp
E/Gp
M [26, 27, 28, 29]
and Gn
E/Gn
M [1, 2, 4, 5, 6, 7, 9] are compared with predictions
of selected models in Fig. 4. The chiral soliton
model [30] reproduces the dramatic linear decrease
observed in オpGp
E/Gp
M for 1 < Q2 < 6 (GeV/c)2; however,
this model fails to reproduce the neutron data at
large Q2. The light-cone diquark model [31] achieves
qualitative agreement with the low Q2 proton and neutron
data; however, at high Q2, it lies below(above) the
proton(neutron) data. A calculation using the pointform
spectator approximation (PFSA) with pointlike
constituent quarks and a Goldstone boson exchange interaction
fitted to the meson and baryon spectrum [32]
also achieves qualitative agreement with the low Q2 proton
and neutron data; however, it, too, fails to describe
the high Q2 proton and neutron data. A light-front calculation
using pointlike constituent quarks surrounded by
a cloud of pions [33] describes the neutron data, but falls
below the proton data at high Q2. A one-gluon exchange
light-front calculation using constituent quark form factors
fitted to Q2 < 1 (GeV/c)2 data [34] agrees with the
neutron data, but deviates from the proton data above


you know!!!!!!!!!!!

MattHiggs
01-03-2006, 09:59:20
The joys of Quantum Physics.

JM^3
01-03-2006, 11:41:28
I just wrote a long thing about it all, but then decided that no one would read it.

It wasn't sounding as good as in my head also.

Jon Miller

mr_G
01-03-2006, 11:55:37
we will read it
we will read it

pleeez jon, post post post!!!!

shagnasty
01-03-2006, 12:02:30
Originally posted by mr_G
4
TABLE II: Results for g = Gn
E/Gn
M and Gn
E.
hQ2i [(GeV/c)2] g = Gn
E/Gn
M Gn
M/オnGD [20] Gn
E
0.447 −0.0761 ア 0.0083 ア 0.0021 1.003 ア 0.006 0.0550 ア 0.0060 ア 0.0016
1.132 −0.131 ア 0.010 ア 0.003 1.057 ア 0.017 0.0394 ア 0.0029 ア 0.0012
1.450 −0.190 ア 0.016 ア 0.004 1.044 ア 0.024 0.0411 ア 0.0035 ア 0.0013
0
0.02
0.04
0.06
0.08
0.1
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
MIT-Bates: d(e5,e地5) [1]
JLab E93-026: d5(e5,e地) [7]
Mainz A1: 3H5
e(e5,e地) [4]
Mainz A3: d(e5,e地5) [2]
Mainz A3: 3H5
e(e5,e地) [5]
NIKHEF: d5(e5,e地) [6]
Schiavilla & Sick [9]
This Work
Q2 [(GeV/c)2]
GE n
FIG. 3: The current world data on Gn
E versus Q2 extracted
from polarization measurements and an analysis of
the deuteron quadrupole form factor [1, 2, 4, 5, 6, 7, 9]. The
Galster parameterization [8] is the dashed line, and our twoparameter
Galster fit (see text) is the solid line.
such that the net e ect upon g is small at hQ2i = 0.45
(GeV/c)2 and negligible at the two higher Q2 points.
The values of g and Gn
E that we report are listed in
Table II. To determine our values for Gn
E, we used the
best-fit values for Gn
M (listed in Table II) obtained using
the methods described in [20]. The new fit omits the data
of [21, 22] and includes the recent data of Xu et al. [23].
The results are similar to those obtained by Friedrich
and Walcher [24] using a parameterization designed to
investigate the role of the pion cloud. The fit is also
similar to that of Kubon et al. [25] within their range of
Q2, but extends to larger Q2. For g and Gn
E, the first set
of errors is statistical, and the second set is systematic.
The quoted systematic uncertainties for g include a 2%
uncertainty that results when a di erent selection of runs
is used for the time calibration. To obtain the systematic
uncertainties for Gn
E, the relative uncertainties in Gn
M
were added quadratically to the systematic uncertainties
listed in Table I and the 2% time calibration uncertainty.
Our values for Gn
E are plotted in Fig. 3 together with
the current world data on Gn
E [1, 2, 4, 5, 6, 7, 9] extracted
from polarization measurements and an analysis
of the deuteron quadrupole form factor. We fitted these
data and the Gn
E slope at the origin as measured via lowenergy
neutron scattering from electrons in heavy atoms
[17] to a Galster parameterization: Gn
E = −aオnτGD/(1+
bτ), where τ = Q2/4M2
n, GD = (1 + Q2/2)−2, and
2 = 0.71 (GeV/c)2. Our best-fit parameters are a =
0.888 ア 0.023 and b = 3.21 ア 0.33.
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4 5 6
JLab Hall A: p(e5,e恥5) [27,29]
Mainz A1: p(e5,e恥5) [28]
MIT-Bates: p(e5,e恥5) [26]
mpGE p
/ GM p
0
0.1
0.2
0.3
0.4
0 0.5 1 1.5 2 2.5 3 3.5
Light-Cone Diquark: [31]
Light-Front OGE: [34]
Light-Front CBM: [33]
VMD + pQCD: [35]
PFSA GBE: [32]
Chiral Soliton: [30]
Q2 [(GeV/c)2]
mnGE n
/ GM n
FIG. 4: Predictions of selected models (see text) for
オpGp
E/Gp
M and オnGn
E/Gn
M compared with proton [26, 27, 28,
29] and neutron [1, 2, 4, 5, 6, 7] data. The neutron data
symbols are the same as in Fig. 3.
Polarization measurements of Gp
E/Gp
M [26, 27, 28, 29]
and Gn
E/Gn
M [1, 2, 4, 5, 6, 7, 9] are compared with predictions
of selected models in Fig. 4. The chiral soliton
model [30] reproduces the dramatic linear decrease
observed in オpGp
E/Gp
M for 1 < Q2 < 6 (GeV/c)2; however,
this model fails to reproduce the neutron data at
large Q2. The light-cone diquark model [31] achieves
qualitative agreement with the low Q2 proton and neutron
data; however, at high Q2, it lies below(above) the
proton(neutron) data. A calculation using the pointform
spectator approximation (PFSA) with pointlike
constituent quarks and a Goldstone boson exchange interaction
fitted to the meson and baryon spectrum [32]
also achieves qualitative agreement with the low Q2 proton
and neutron data; however, it, too, fails to describe
the high Q2 proton and neutron data. A light-front calculation
using pointlike constituent quarks surrounded by
a cloud of pions [33] describes the neutron data, but falls
below the proton data at high Q2. A one-gluon exchange
light-front calculation using constituent quark form factors
fitted to Q2 < 1 (GeV/c)2 data [34] agrees with the
neutron data, but deviates from the proton data above


you know!!!!!!!!!!!

Thats easy for you to say!!!

mr_G
01-03-2006, 12:03:10
I know!!!!!!

mr_G
01-03-2006, 12:03:33
well actually i do not, ssssssht don't tell.

shagnasty
01-03-2006, 12:04:33
we'll have to whisper then, someone might hear!!!

mr_G
01-03-2006, 12:11:33
[whisper mode]jesjes[/whisper mode]

shagnasty
01-03-2006, 12:14:26
[whisper mode]:lol: :lol: [whisper mode]

mr_G
01-03-2006, 12:15:41
[whisper mode]pssssshst you are still in whisper mode.....need to / it......jesjes[/whisper mode]

shagnasty
01-03-2006, 12:18:17
[whisper mode]jesjes I am. i'm making notes of the plan also[whisper mode]

mr_G
01-03-2006, 12:19:19
[japanese whisper mode]ok, i will take care of the supplies[/japanese whisper mode]

Funko
01-03-2006, 12:20:23
[whisper mode]the element of supplies is always important[/whisper mode]

mr_G
01-03-2006, 12:21:30
absolute

[whisper mode]damn damn damn now they know[/whisper mode]

shagnasty
01-03-2006, 12:21:51
[whisper mode]and ruthles efficiancy[whisper mode]

mr_G
01-03-2006, 12:23:06
[whisper mode]and i feel sorry for the elephants[whisper mode]

shagnasty
01-03-2006, 12:25:11
[whisper mode]don't mention the elephants. they'll hear you and panic jesjes they will[whisper mode]

mr_G
01-03-2006, 12:26:39
[whisper mode]schjmart thinking, we cannot use a stampeter right now!!![whisper mode]

shagnasty
01-03-2006, 12:28:41
[whisper mode]we shall wait for the hamster attack then call forth the elephants[whisper mode]

Funko
01-03-2006, 12:29:17
Hey, MrG, you made an error in your calculations. Stupid boy. Do it again.

Tizzy
01-03-2006, 12:31:59
Originally posted by shagnasty
[whisper mode]we shall wait for the hamster attack then call forth the elephants[whisper mode]

[panic mode] but there's too many hamsters - they've been breeding! [/panic mode]

mr_G
01-03-2006, 12:32:07
4
TABLE II: Results for mrG = Gn
E/Gn
M and Gn
E.
hQ2i [(GeV/c)2] g = Gn
E/Gn
M Gn
M/オnGD [20] Gn
E
0.447 −0.0761 ア 0.0083 ア 0.0021 1.003 ア 0.006 0.0550 ア 0.0060 ア 0.0016
1.132 −0.131 ア 0.010 ア 0.003 1.057 ア 0.017 0.0394 ア 0.0029 ア 0.0012
1.450 −0.190 ア 0.016 ア 0.004 1.044 ア 0.024 0.0411 ア 0.0035 ア 0.0013
0
0.02
0.04
0.06
0.08
0.1
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
MIT-Bates: d(e5,e地5) [1]
JLab E93-026: d5(e5,e地) [7]
Mainz A1: 3H5
e(e5,e地) [4]
Mainz A3: d(e5,e地5) [2]
Mainz A3: 3H5
e(e5,e地) [5]
NIKHEF: d5(e5,e地) [6]
Schiavilla & Sick [9]
This Work
Q2 [(GeV/c)2]
GE n
FIG. 3: The current world data on Gn
E versus Q2 extracted
from polarization measurements and an analysis of
the deuteron quadrupole form factor [1, 2, 4, 5, 6, 7, 9]. The
Galster parameterization [8] is the dashed line, and our twoparameter
Galster fit (see text) is the solid line.
such that the net e ect upon g is small at hQ2i = 0.45
(GeV/c)2 and negligible at the two higher Q2 points.
The values of g and Gn
E that we report are listed in
Table II. To determine our values for Gn
E, we used the
best-fit values for Gn
M (listed in Table II) obtained using
the methods described in [20]. The new fit omits the data
of [21, 22] and includes the recent data of Xu et al. [23].
The results are similar to those obtained by Friedrich
and Walcher [24] using a parameterization designed to
investigate the role of the pion cloud. The fit is also
similar to that of Kubon et al. [25] within their range of
Q2, but extends to larger Q2. For g and Gn
E, the first set
of errors is statistical, and the second set is systematic.
The quoted systematic uncertainties for g include a 2%
uncertainty that results when a di erent selection of runs
is used for the time calibration. To obtain the systematic
uncertainties for Gn
E, the relative uncertainties in Gn
M
were added quadratically to the systematic uncertainties
listed in Table I and the 2% time calibration uncertainty.
Our values for Gn
E are plotted in Fig. 3 together with
the current world data on Gn
E [1, 2, 4, 5, 6, 7, 9] extracted
from polarization measurements and an analysis
of the deuteron quadrupole form factor. We fitted these
data and the Gn
E slope at the origin as measured via lowenergy
neutron scattering from electrons in heavy atoms
[17] to a Galster parameterization: Gn
E = −aオnτGD/(1+
bτ, where τ = Q2/4M2
n, GD = (1 + Q2/2)−2, and
2 = 0.71 (GeV/c)2. Our best-fit parameters are a =
0.888 ア 0.023 and b = 3.21 ア 0.33.
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4 5 6
JLab Hall A: p(e5,e恥5) [27,29]
Mainz A1: p(e5,e恥5) [28]
MIT-Bates: p(e5,e恥5) [26]
mpGE p
/ GM p
0
0.1
0.2
0.3
0.4
0 0.5 1 1.5 2 2.5 3 3.5
Light-Cone Diquark: [31]
Light-Front OGE: [34]
Light-Front CBM: [33]
VMD + pQCD: [35]
PFSA GBE: [32]
Chiral Soliton: [30]
Q2 [(GeV/c)2]
mnGE n
/ GM n
FIG. 4: Predictions of selected models (see text) for
オpGp
E/Gp
M and オnGn
E/Gn
M compared with proton [26, 27, 28,
29] and neutron [1, 2, 4, 5, 6, 7] data. The neutron data
symbols are the same as in Fig. 3.
Polarization measurements of Gp
E/Gp
M [26, 27, 28, 29]
and Gn
E/Gn
M [1, 2, 4, 5, 6, 7, 9] are compared with predictions
of selected models in Fig. 4. The chiral soliton
model [30] reproduces the dramatic linear decrease
observed in オpGp
E/Gp
M for 1 < Q2 < 6 (GeV/c)2; however,
this model fails to reproduce the neutron data at
large Q2. The light-cone diquark model [31] achieves
qualitative agreement with the low Q2 proton and neutron
data; however, at high Q2, it lies below(above) the
proton(neutron) data. A calculation using the pointform
spectator approximation (PFSA) with pointlike
constituent quarks and a Goldstone boson exchange interaction
fitted to the meson and baryon spectrum [32]
also achieves qualitative agreement with the low Q2 proton
and neutron data; however, it, too, fails to describe
the high Q2 proton and neutron data. A light-front calculation
using pointlike constituent quarks surrounded by
a cloud of pions [33] describes the neutron data, but falls
below the proton data at high Q2. A one-gluon exchange
light-front calculation using constituent quark form factors
fitted to Q2 < 1 (GeV/c)2 data [34] agrees with the
neutron data, but deviates from the proton data above

mr_G
01-03-2006, 12:32:29
better?

Funko
01-03-2006, 12:33:19
Yeah, was obvious really

mr_G
01-03-2006, 12:33:52
yaaaay what was I thinking

shagnasty
01-03-2006, 12:36:09
[whisper mode]*looks round slyly*i thing they've been listening G. jesjes i'm sure they have. we shall have to whisper our whispers[whisper mode]

Tizzy
01-03-2006, 12:39:19
You know, whispering can make people paranoid [/whisper]

mr_G
01-03-2006, 12:41:20
Originally posted by shagnasty
[whisper mode]*looks round slyly*i thing they've been listening G. jesjes i'm sure they have. we shall have to whisper our whispers[whisper mode]

[whisper mode]beware of the awareness, and never tell never never never [/whisper mode]

mr_G
01-03-2006, 12:42:11
[extreme whisper mode]let's try the extreme whispering [/extreme whisper mode]

MoSe
01-03-2006, 12:42:27
Originally posted by Funko
Yeah, was obvious really sameold オrG

mr_G
01-03-2006, 12:42:49
[lethal whisper mode]kill kill kill [/lethal whisper mode]

MoSe
01-03-2006, 12:46:34
http://perso.wanadoo.fr/listephilo/munch.jpeg

shagnasty
01-03-2006, 12:47:55
[extreme whisper mode]nono not yet. it seems to be working though, but it was close. are the kamikazee elephants on stand-by?[extreme whisper mode]

mr_G
01-03-2006, 12:47:55
pic is stolen

mr_G
01-03-2006, 12:49:25
[extremely extreme whisper mode]jesjes on stand by, next to the ninja earthworms[extremely extreme whisper mode]

shagnasty
01-03-2006, 12:50:23
mmmmmm stolen

mr_G
01-03-2006, 12:50:41
[extremely extreme whisper combat mode]we will attack the moment baby shag pops out[/extremely extreme whisper combat mode]

shagnasty
01-03-2006, 12:52:20
[extreme whisper mode]good. remember to keep the ninja worms away from the mighty moles of mayhem[extreme whisper mode]

shagnasty
01-03-2006, 13:02:52
[extreme whisper mode]where should we aim for?[extreme whisper mode]

mr_G
01-03-2006, 13:04:54
[extreme whisper mode]a good swing between his big toes?[extreme whisper mode]

mr_G
01-03-2006, 13:06:20
Originally posted by Tizzy
[panic mode] but there's too many hamsters - they've been breeding! [/panic mode] bhaaaawaaaaaahaaa :cry: she is right, funko do dome thing about that


[whisper mode] damn [/whisper mode]

shagnasty
01-03-2006, 13:09:45
[extreme whisper mode]jesjes, but where is he hiding?[extreme whisper mode][extreme whisper mode]p.s. the hamsters are under control. it's the hamPsters that a a major concern at the mo[extreme whisper mode]

nonono i didn't edit nonono

Tizzy
01-03-2006, 13:19:42
Originally posted by mr_G
bhaaaawaaaaaahaaa :cry: she is right, funko do dome thing about that


He won't help, he thinks it's funny :cry:

Japher
01-03-2006, 13:26:17
what's going on here!

shagnasty
01-03-2006, 13:32:44
nothing officer *whistles tune*

mr_G
01-03-2006, 13:47:12
don't tell the americans, if they know they will invade some country.

shagnasty
01-03-2006, 13:52:03
that is called friendly fire jesjes it is

Japher
01-03-2006, 13:52:48
That's it, I'm invading Canada!

mr_G
01-03-2006, 13:53:51
lesson one: never invade canada in the winter you schjtoepit!!!

Japher
01-03-2006, 14:11:04
Oh... I'll wait then. Just don't tell any of them, as it's going to be a sneak attack

shagnasty
01-03-2006, 14:14:29
[ultra-frequency whisper mode]phew, that was lucky. japhertje nearly ruined the whole thing[ultra-frequency whisper mode]

Tizzy
01-03-2006, 14:14:35
They'll never find out, there's no Canadians here.
Especially not a Canadian of the year.

mr_G
01-03-2006, 14:17:13
jesjes he izzzz lurking, he knows you know

[proper english mode] the americans can't read this, this is a code[/proper english mode]

shagnasty
01-03-2006, 14:17:31
[ultra-frequency whisper mode]dammit. now tizzy is spying, schsssshhhhht[ultra-frequency whisper mode]dooooo-di-doooooo

Japher
01-03-2006, 14:18:35
dooooooo-di-dooooooo?

Is that code?!

mr_G
01-03-2006, 14:18:44
[ultra-frequency whisper mode] cars cars cars boobs beer cars so I scared here away[/ultra-frequency whisper mode]

shagnasty
01-03-2006, 14:21:52
[ultra-frequency whisper mode]nono she likes beer[ultra-frequency whisper mode]

mr_G
01-03-2006, 14:22:28
[ultra-frequency whisper mode]nono she likes wine / cider you fewl[ultra-frequency whisper mode]

shagnasty
01-03-2006, 14:24:28
[ultra-frequency whisper mode]sorry. i was using beer in the generic form[ultra-frequency whisper mode]

mr_G
01-03-2006, 14:27:34
in a biblical way!!!!!!

shagnasty
01-03-2006, 14:52:45
jesjes that as well