1. Deuteron and Small Aperture
Yuhong Zhang
February 7 , 2019

2. Electron-Deuteron Luminosity
CM energy
GeV
31.6
44.7 D e p
Beam energy
GeV/u 50 5
100
Collision frequency
MHz
476
Particles per bunch
1010
0.42
3.9
Beam current A
0.32 3
Polarization % 80
Bunch length, RMS cm 1 2
Norm. emitt., horiz./vert. μm
0.5/0.1
90/18
0.5/ 0.1
Horiz, & verti. β*
6.75/1.35
13.5/ 13.5
16.5/3.3
8.4/1.7
Vert. beam-beam param.
0.008
0.02
Laslett tune-shift
0.024
0.006
Detector space, up/down m
3.6/7
2.96/2.2
Hourglass(HG) reduction
0.8
0.85
Lumi./IP, w/HG, 1033
cm-2s-1
3.45

3. Magnet Aperture: A Great Opportunity to Exploit?
Cooling No
Yes
Kinetic energy
GeV 8
Injection 50
100
210 10
injection
CM energy
(Electron energy)
24.7
(3 GeV)
69.6
(12 GeV)
100.6
Emittance, normalized µm
2.5
0.5
0.5 / 0.25
0.5 / 0.1
Emittance, unnorm. nm
266.9
46.1
23.2
11.1
43.0
9.2 / 4.6
4.6 / 0.93
2.2 / 0.44
Energy spread (δp/p)
10-4 3
Maximum beta in arc m 38
Maxi dispersion in arc
2.2 / 0
2.3 / 0
Max beam size in arc mm
3.9 / 3.2
2.6 / 1.3
2.4 / 0.94
2.3 / 0.65
1.4 / 1.3
0.89 / 0.42
0.78 / 0.19
0.72 / 0.13
Beam stay-clear
39 / 32
(10 σ)
26 / 13
23.9 / 9.4
24 / 6.5
8.2 / 7.7
(6 σ)
5.3 / 2.5
4.7 / 1.1
4.3 / 0.8
Magnet saggitt
18.3
Beam steering
± 5
Required phys. Aperture
106 x 74
80 x 37
76 x 29
74 x 23
46 / 25
39 / 15
38 x 12
37 / 12
42% x 34%
Is a 50 mm x 30 mm aperture enough?
100 mm x 60 mm is the present baseline
Can we get away with a half-size aperture for the JLEIC ion collider ring high-field dipoles so we can save half the cost?
Oct