Overview of 2020c and2021a/b Run
Y. Ohnishi
September 1, 2021
The 25th KEKB Review Meeting

Achievements
in 2020c and 2021a/b

2

a: February - Marchb: April - Julyc: October - December

SuperKEKB Operation Summary
Peak Luminosity : 3.12 x 1034 cm-2s-1

2019a/b

2019c

2020a/b2020c

2021a/b"TMCI"
carbon collimator

Belle IIoff

βy* 3 → 2 mm

Belle IIoff

βy* 2 → 1 mm

Belle IIon

βy* 1 → 0.8 mm

Belle IIon

βy* 1 mm

Operation time
6 - 7 months per year
int. Lrecorded

int. LdeliveredShift

747.2 pb-1
May 18 swing

797.6 pb-1
June 22 dayDay

1.964 fb-1
May 182.233 fb-1
May 227 daysMay 14 - 20

12.141 fb-1

13.482 fb-1

30 days
May 18 - June
23

42.319 fb-1

47.370 fb-1

2021ab140 days123.2 fb-1

138.6 fb-1

total

213.5 fb-1

βy* 1 mm3

2020c Operation Summaryβy∗ = 1 mm<latexit sha1_base64="AHmtJdXLvtZjKQ9UQoYTW8HTTpY=">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</latexit>• The 2020c run started on 20th October and

600 mA Large background due tooperated for 60 days (2 months).

bad BTe parameter• The first ten days were devoted to the vacuum
scrubbing.
700 mA• D06V1 was carbon head collimator (new). We
observed TMCI threshold which was 0.3 mA/bunch.

vacuumscrubbingLER D02V1 vacuum
replacement scrubbing
vacuum leak• BTe parameter was wrong until November 11.
HER background was large until the correction.

• D02V1(LER) head was replaced due to damage(November 18). The vacuum leak was foundduring the vacuum scrubbing in the LER. The
replacement process was not good. The
vacuum scrubbing was agin performed after
fixing the trouble.

• Beam abort due to misfire of the injection
kicker in the LER. The D06H3 collimator head
was damaged due to the beam hitting.

• D06V1 carbon head was replaced with tantalum
head during the winter shutdown after 2020c.
42021a/b Operation Summaryβy∗ = 2 mm<latexit sha1_base64="i8hb80pv1bomaFNfz46vRn7qm/Y=">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</latexit>

D01V1 headreplacementβy∗ = 1 mm

D02V1 headreplacement

HER BxB FB noise is ﬁxed.
NIM bin and fanout replacement<latexit sha1_base64="AHmtJdXLvtZjKQ9UQoYTW8HTTpY=">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</latexit>• The 2021a run started on 16th February andoperated for 140 days (4 months and half).
940 mA• The first ten days were devoted to the vacuum
scrubbing.

• We operated with βy* = 2 mm to checkhardwares and to test high current operation
safely.

1000 mA• Calibrations of BPM and collimator head
Lp 3.12x1034
HER many aborts
BxB FB noise

positions, etc. were also performed by using
beams during the first two weeks.

• D01V1(HER) head was replaced. D01V1(HER)
head was replaced. The top-jaw was for the
LER collimator head and it was the short length
in the HER. (March 23).

• We squeezed βy* down to 1 mm on 10th
March. Beam currents increased with "bakingrun". 1000 mA / 940 mA w/o physics run• HER many aborts from April 20 to May 3.
• D02V1(LER) head was replaced due damage(June 7).

5

Machine Parameters (2020b and 2021b)
2020b : June 21, 2020

2021b : June 22, 2021

Ring

LER

HER

LER

HER

Emittance

4.0

4.6

4.0

4.6

nm

Beam Current

712

607

790

687

mA

978

Number of bunches

Unit

1174

Bunch current

0.728

0.621

0.673

0.585

mA

Lifetime

760

1270

540

1320

sec

Horizontal size σx*

17.9

16.6

17.9

16.6

μm

Vertical cap sigma Σy*

0.403

0.324

μm*1

Vertical size σy*

0.285

0.229

μm*2

Betatron tunes νx / νy45.523 / 43.581 44.531 / 41.577 44.524 / 46.596 45.532 / 43.581

βx* / βy*80 / 1.0

60 / 1.0

80 / 1.0

60 / 1.0

Piwinski angle

10.7

12.7

10.7

12.7

Crab Waist Ratio

80

40

80

40

Beam-Beam parameter ξy

0.039

0.026

0.046

0.030

mm
%

Speciﬁc luminosity

5.43 x 1031

6.76 x 1031

cm-2s-1/mA2

Luminosity

2.40 x 1034

3.12 x 1034

cm-2s-1*1) estimated by luminosity with assuming design bunch length*2) divide *1 by √2

6

Bunch Length Measurement
measured in 2020c
H. Ikeda

1L∝
φ x σzrεyβy∗<latexit sha1_base64="rB5LDIYF+duXvL6w2mWkEm6LEAU=">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</latexit>
sha1_base64="xOeqHam/TZST18F20gnp4YTbjSc=">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</latexit>
sha1_base64="SnayaM+GEwMd2Nvegqo6xEmxjc8=">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</latexit>
sha1_base64="212Q0I1OxHabFdzc01Yi06O/Kzo=">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</latexit>

Bunch lengthening deteriorates
the luminosity.

nominalσz (mm)

σδ

αp

νs

U0 (MeV)Vc (MV)HER

5.05

6.30 x 10-4

4.54 x 10-4

-0.0272

2.43

14.18

LER

4.60

7.53 x 10-4

2.98 x 10-4

-0.0233

1.76

9.13
7

Working Point
The circle indicates nominal working point in 2021b.

2νx + 2νs = int.

2νx + 2νs = int.
<latexit sha1_base64="mK8FQDNfBMyxVIEaAZlmDe+i3FI=">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</latexit>
sha1_base64="bXshH0XV/k2I4XskDsmNQo4vSTA=">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</latexit>
sha1_base64="FnMYlZoxNIWQB3Sta6+CKSh7qkY=">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</latexit><latexit sha1_base64="mK8FQDNfBMyxVIEaAZlmDe+i3FI=">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</latexit>
sha1_base64="bXshH0XV/k2I4XskDsmNQo4vSTA=">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</latexit>
sha1_base64="FnMYlZoxNIWQB3Sta6+CKSh7qkY=">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</latexit>2νx + 3νs = int.
<latexit sha1_base64="a4ijoDdnn0AKFtGgNhuOgo/q2TU=">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</latexit>
sha1_base64="7wdB1HfRZfrfddXTQ1iRStAvyB0=">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</latexit>
sha1_base64="DCli5PZt476uJDeeUGOHChRlG4w=">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</latexit>2νx + 3νs = int.
<latexit sha1_base64="a4ijoDdnn0AKFtGgNhuOgo/q2TU=">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</latexit>
sha1_base64="7wdB1HfRZfrfddXTQ1iRStAvyB0=">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</latexit>
sha1_base64="DCli5PZt476uJDeeUGOHChRlG4w=">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</latexit>

This resonance is very strong.
Injection background and SR on PXD
are caused significantly.
8

Definition of specificluminosity
2021bHigh Bunch Current
Collision (393 bunches)<latexit sha1_base64="FYh+scf6Lee0h8uMDl0vsyyXnuw=">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</latexit>

Lsp =

L
nb Ib+ Ib−

No CW for βy* = 2 mm

• Specific luminosity for βy* = 1 mm is improved compared to that of 2020ab.
• X-Y couplings at IP are improved by using local correctors with luminosity optimization.
• We also use chromatic X-Y coupling correctors.
• Bunch current product is achieved larger than 0.5 mA2 with crab waist scheme.
9Projection of Specific Luminosity in 2021a/b
Definition of specificluminosity

Lsp =<latexit sha1_base64="6ONMonm/9fulghNMOrXdUf6O3T4=">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</latexit>
sha1_base64="JdbJi1V5mTxm5Vr/XbfbXjGzUVY=">AAAChXichVE7S8RAEP6M7/N1aiPYHIoiiMdExBeIBzYKFr5OBZWQxD0N5pKQ5A40BKwsbC0srBRERFsFaxv/gIU/QSwVbCyc5BQRUWfZ3dlv55v5ZldzTMPziR7KpPKKyqrqmtpEXX1DY1OyuWXRswuuLrK6bdrusqZ6wjQskfUN3xTLjivUvGaKJW1rIrpfKgrXM2xrwd92xFpe3bCMnKGrPkNKMjWtBJ4Tjq3mXFUPpsPAUrQpJdB6w2jtC0Ml2UnpEZJHBuXUT0dOU2ydmbGDm10AM3byDKtYhw0dBeQhYMFn34QKj8cKZBAcxtYQMOayZ8T3AiESzC1wlOAIldEtXjf4tPKBWnyOcnoxW+cqJk+XmSl00T2d0zPd0QU90tuvuYI4R6Rlm3etxBWO0rTfNv/6LyvPu4/NL9afmn3kMBxrNVi7EyNRF3qJX9w5fJ4fnesKuumEnlj/MT3QLXdgFV/001kxd4QEf8DnK6d+dxb70zKl5Vn+iQxKVoN2dKCH33sIGUxiBlmuu4dLXOFaqpb6pAFpsBQqlX1wWvHNpPF3giSY+w==</latexit>
sha1_base64="Ld8RmETu1dJCbgTqjaxXqJD7rR8=">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</latexit>
sha1_base64="L0i1ciXs9EirVu4JeKXja7IarNs=">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</latexit>

Lnb Ib+ Ib−

LER / HER : 1.1 A / 1.0 Anb = 1565
max of nbIb+Ib- is 540 mA2 target of 2021b(840 mA/818 mA, nb = 1272)
700 mA2

L=

numberofbunches10

Beam Background and Beam Aborts due to Beam Lossstored beam and injection beam
radiation dose (serious) at collimators, collimator damage, Belle II detector damage→ risks for increasing beam currents
Collimator Impedance : TMCI thresholdnarrow collimator aperture (physical aperture)
The lower threshold limits bunch current.
Short Lifetime
small dynamic aperture and/or small physical aperture (collimators, QCS aperture, etc.)
Beam-Beam Blowup
Is the source of blowup the chromatic X-Y couplings ?
single beam blowup or multi bunch effect ? How about BxB FB gain ?
→ Those enhance beam-beam blowup ? How about BBHT(XZ) ?
Insufficient Understood of Injection Beamemittance, orbit fluctuation, energy spread, stability of injector linac
11

TMCI in LER

12LER Collimator Impedance due to Carbon Head in 2020c

December 17, 2020 17:46 - 17:54
D03V1 open →(nm)

TMCI threshold
εy = 90 pm

Single Beam Operation(No collision)νy = 46.586<latexit sha1_base64="clsgLsTujT4jgBxD6+AQMxVe3Wk=">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</latexit>
sha1_base64="elo294WwgaC87i7QScER+HemLtA=">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</latexit>
sha1_base64="iH+xtxeJvFjXMmD2eDi/eXKQd8c=">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</latexit>

D06V1 (carbon) open →νs = −0.0235

εy = 22.5 pm<latexit sha1_base64="d0MeoqsnyYssj6rLpfn7z/vQe5I=">AAACcHichVHLSsNAFD2N7/po1Y3gwkdRRLDc+EARhIIbl776gFpKEkcNTZOYpIVa/AF/wIUbFUTEz3DjD7joJ4g7K7hx4W0aEC3qHWbmzJl77pyZUW1Ddz2iWkhqa+/o7OruCff29Q9EooNDKdcqOZpIapZhORlVcYWhmyLp6Z4hMrYjlKJqiLRaWG/sp8vCcXXL3PUqtsgVlUNTP9A1xWMqt2eW8u7aHMVpfmEpH40x8GO8FcgBiCGITSt6iz3sw4KGEooQMOExNqDA5ZaFDILNXA5V5hxGur8vcIowa0ucJThDYbbA4yGvsgFr8rpR0/XVGp9icHdYOY4peqI7qtMj3dMzffxaq+rXaHip8Kw2tcLOR85Gdt7/VRV59nD0pfrTs4cDrPhedfZu+0zjFlpTXz45r++sbk9Vp+maXtj/FdXogW9glt+0my2xfYEwf4D887lbQWo+LlNc3lqMJRLBV3RjFJOY4fdeRgIb2ESSzz3GOS5xFXqVRqQxaaKZKoUCzTC+hTT7CSdQjZk=</latexit>

sidebandLER

single bunch tune shift
H: -0.0019 (mA-1)
V: -0.0229 (mA-1)

We observed TMCI in the LER at the operation beam current.
TMCI threshold depends on the collimator aperture.
The threshold also depends on the vertical tune. → localized impedance?
13

LER Collimator Impedance
2021b Run

Transverse Mode Coupling Instability (TMCI)
Kick factor depends on collimator aperture (vertical).

Σ βy κ = 36 (V/pC) on June 30
sum of βy x kick factor ( V/pC)

CGLOPT:SUM:BETA_KICK:V"TMCI" threshold

T0 Ith i βyi κiνs∆νy,th =
=
4πE/e
2
νs
fs =
fs = 2.3325 (kHz)*T0

collimatoropened (for test)<latexit sha1_base64="PD1zxbHULJ0mlj+w4Afvsl8Gn/A=">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</latexit>* measured value (M. Tobiyama)

vertical tune shift : -0.013 (1/mA)
LER Vertical TuneP

LER Bunch Current (mA)

Injection bunch charge : 2 nC

LER Vertical Emittance (pm)nb= 97 bunches

LER bunch current (mA)

2πfs (E/e)
Ith = P= 1.6 mA > 0.9 mA (measured)i βyi κi<latexit sha1_base64="zlcCAqAw4QZg1HmbxXyeNi9mRG0=">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</latexit>

The measured threshold is much lower than expected.
The kick factor is estimated by using GdﬁdL simulator.
Simple TMCI formula can not explain it.

14

Calculation of GdﬁdL Electromagnetic Field Simulator

T. Ishibashi

Length(along beam axis) of head : 10 mm

1 (V/pC/m)

Zagorodnovʼs equationk⊥ = 0.215AZ0c

α
σzd 3

[I. Zagorodnov, Wakeﬁeld Calculations for 3D Collimators,
EUROTeV-Report-2006-074.]

15

Luminosity Tuning

16

IP Knobs for X-Y couplings,
dispersions

A. Morita
H. Koiso

IP Knobs forchromatic X-Y couplings

17

IP Knob Scan for Luminosity Tuning
A

B

C

D

Vertical beam size2

σy∗2 = µ2 εy

✓

2

∆s
∗
βy + ∗
βy

◆

2
∗
∗
∆s)
+
R
(R
4
2
∗
2
∗
∗
∗
2
+ (ηy σδ ) + εx
+
ε
β
(R
+
R
∆s)
x x
1
3
∗
βx

<latexit sha1_base64="iUGJ1ZCEkqrujctoLaBBUGsZspI=">AAADSHichZHPaxNBFMffbv1R449GvQheFkMlaSDMroIiCEU96K1NTVvoNMvsdpIOnf3B7CRkXfIP+A948KRQivhneBHvHnr2JF6ECkXw4NvNahuL+padefOd93nvzYwXS5FoQvYNc+bU6TNnZ89Vzl+4eGmuevnKahINlM87fiQjte6xhEsR8o4WWvL1WHEWeJKveTsP8/21IVeJiMKnOo35ZsD6oegJn2mU3Oonmoh+wNy0my04Y+u+ZdFg0HXokCkeJ0JiTEol7+k69bjO4xaatKeYn9FHXGpmJV1nnP3eG1Ml+tu60azTUinz0608utF1KtYxa1rHC40miett18Eqbfc20mWRxlGVEVZpTmO/dCTtgrw1RbrVGmmRwqyTjl06NShtKaruAYUtiMCHAQTAIQSNvgQGCX4bYAOBGLVNyFBT6Ilin8MYKsgOMIpjBEN1B8c+rjZKNcR1njMpaB+rSPwVkhbMk4/kDTkg78lb8pn8+GuurMiR95Li7E1YHrtzz6+tHP6XCnDWsH1E/bNnDT24W/QqsPe4UPJT+BN++OzFwcq99nx2k7wmX7D/V2SfvMMThMNv/u4yb7+ECj6A/ed1n3RWnZZNWvYyqS0+KJ9iFq7DDajjfd+BRXgMS9AB33hiRMbISM0P5lfz0Pw+CTWNkrkKUzZj/gTOQdqM</latexit>
sha1_base64="k8WXVgUN7yllajwAYCL5WXDQAmM=">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</latexit>
sha1_base64="CkPumyr/hyQIi+PWIaWWU85tzEU=">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</latexit>Δs : waist shift
IP X-Y/Dispersion Knobs

If Δs = 0, R1* and R2* are elementary parameters to improve the luminosity.

LER / HER

R2* in HER changed due to the QC1P skew quadrupole leakage field.
LER: R2* and R1*(QC1P)

R1* and R2* are almost fixed to optimize luminosity.

No iron shield on QC1P in LER

R3* and R4* affect beam background.
19

IP Chromatic X-Y Coupling Knobs

LER / HER

K. Ohmi, KEKB Review 2018

IP knob is separated for X-Y coupling and chromatic knobs.
(new knobs)
A. Morita• Sextupole magnet mounted on rotating table is utilized
since March 11 to suppress chromatic X-Y at IP(model).
• Corrector strength and/or BG sometime limits the knob.
• Reduction of Beam-Beam blowup is not clear so far.

20

LER
r1

r2

0.2
0.15
0.1

0.02

r1

HER

Chromatic X-Y couplings at the IP measured
by using TBT BPMs
r1

0.2

r2

0.015
0.01

0.15

G. Mitsuka

r2
0.025

r1

0.02
0.015

0.1
0.01

0.05

0.005

0.05

0

0

0

− 0.05− 0.005− 0.05− 0.1− 0.01

− 0.1

0.005
0
− 0.005− 0.01− 0.015− 0.15− 0.2− 0.015− 0.002− 0.001

0

0.001

0.002

− 0.001

0

dp

r3

r4

0.001

0.002

0.1

r3

0.06

1

0.5

− 0.002− 0.001

0

0.001

0.002

dp

Accuracy of measurement
is under consideration.

r4

0.08

1.5

0

− 0.002

dp

2.5

2

− 0.02− 0.15
− 0.2

1.5

0.04

1

0.02

0.5

0

0

− 0.02− 0.5− 0.04−1− 0.06− 1.5− 0.08−2− 0.1− 0.002− 0.001

0

0.001

− 2.5

0.002

− 0.02− 0.001− 0.001

0

dp

dp

r3

r4

r3

0.001

0.2

r4

0.1

0

− 0.1

− 0.2

− 0.001

0

− 0.3

0.001

dp

IP chromatic knob on
r1
r2
r3
r4

− 0.025

0.001

0.3

dp

r
-6.034x10-2-6.763x10-3
1.318-2.319x10-2

0

2.5
2

r2

− 0.001

0

0.001

dp

IP chromatic knob on

dr/dδ-7.764-1.254
214.6
45.24

r1
r2
r3
r4

IP chromatic knob off

r

dr/dδ

1.69x10-2
1.317x10-2-0.2772-0.1637-1.644
2.028
733.0
26.81

IP chromatic knob off

r1-4.634x10-2-4.379r1-2.095x10-2-25.99r2-9.726x10-3-2.079r2

1.2x10-2-0.4769

r3

1.678

185.0

r3

-0.5715652.4

r4

9.563x10-3

37.54

r4

-0.1142

24.53

21

Lifetime

22

LER

nb:1174

Beam Lifetime and Vertical EmittanceHER

currentver. emittance
60 pm

nb:393
nb:393

28 pm

22 pm

collision

40 pm

45 pm

25 pm

LER

HER

βx*

80 mm

60 mm

βy*

1 mm

1 mm

I

800 mA

650 mA

nb

1174

1174

Ib

0.681 mA

0.545 mAεycollision

60 pm

45 pm

25 pm

40 pm

8 min

30 min6 min

32 min1174

nb:1174

1174

single beamcollision

single beamεy depends on bunch current.

εysinglelife
collision

Lifetime

life
single30 min8 min

26 min32 min

7 min

6 min

e+inj: 2.3 nC x 2 x 12.5 Hz x 80 %Imax= 1.5 A for lifetime: 8 min(TMCI limit : 1.4 A with nb:1565)
23

LER : CW 80 %Tracking Simulation
No Machine Error

LER : CW 0 %single beam

800 mA / nb:1174

single beam

800 mA / nb:1174

no collimators

εy = 25 pm

no collimators

εy = 25 pm
26.3 min7.55 minsingle beamwith collimators

800 mA / nb:1174
εy = 25 pm
7.45 minsingle beam

800 mA / nb:1174

with collimators

εy = 25 pm

Touschek lifetime
is similar to CW 80%
with collimators.

11.2 minThe simulation is consistent
with the measured lifetime
for CW 80 %.
24

HER : CW 40 %Tracking Simulation
No Machine Error

HER : CW 0 %single beam

650 mA / nb:1174

single beam

650 mA / nb:1174

no collimators

εy = 40 pm

no collimators

εy = 40 pm
67 min57.7 minsingle beamwith collimators

650 mA / nb:1174
εy = 40 pm
46.5 minsingle beam

650 mA / nb:1174

with collimators

εy = 40 pm

Touschek lifetime
is similar to CW 40%
with collimators.

46.6 minThe simulation is longer
than the measured lifetime
for CW 40 %.
46 min > 32 min25

10.8 minsingle beam
no collimators
LER : CW 80 %800 mA / nb:1174
εy = 60 pm
10.5 minwith beam-beam (W-S)
no collimators
LER : CW 80 %800 mA / nb:1174
εy,LER = 60 pm
650 mA / nb:1174
εy,HER = 45 pm

39.2 minsingle beamwith collimators
LER : CW 80 %800 mA / nb:1174
εy = 60 pm

with beam-beam (W-S)
no collimators
LER : CW 0 %10.5 min

800 mA / nb:1174
εy,LER = 60 pm
650 mA / nb:1174
εy,HER = 45 pm

10.5 min (sim.) > 8 min (meas.)

26

Lifetime and Vertical EmittanceLER
εy is 22 pm - 25 pm for the single beam.
εy increases up to 60 pm due to beam-beam blowup at 800 mA(0.68 mA/bunch).
The luminosity reduction is 65 %.
The DA can almost explain the measured lifetime.
The crab waist reduces the DA. But the tight collimators reduce the PA significantly. The collimators makesmall difference between CW 0 % and CW 80 %.
The lifetime is about 8 min for collision at 800 mA. It is quit shorter than what we expected.
In the case of no CW and no Collimators, Touschek lifetime depends on εy in the tracking simulation.
HER
εy is 28 - 40 pm which depends on the bunch current.
Beam-beam blowup is mild. It is from 40 pm to 45 pm at 650 mA(0.55 mA/bunch).
The collimators reduce the PA significantly. It is same as the LER.
The measured lifetime is shorter than the simulation. (32 min < 46 min; vacuum lifetime not included )27

Beam-Beam Blowup

28

small number of bunches nb : 393 (12.25 spacing)

Vertical emittance (HER)

Horizontal emittance (XRM) (nm)High Bunch Current Collision

LER
HER

Vertical emittance (LER)

Horizontal emittance (LER)• We observed large beam-beam blowup in the LER from40 pm to 250 pm.
• It depends on the HER beam current.
• Horizontal emittance also increases in LER.
We consider coherent beam-beam head-tail instability(BBHT(XZ)) and/or dynamic beta/emittance effect.

Vertical emittance (XRM) (pm)Bunch current (opposite beam) (mA)

LER
HER

Bunch current (opposite beam) (mA)29

Vertical emittance (XRM) (pm)Horizontal emittance (XRM) (nm)

LER

HER

Bunch current (mA)

Bunch current (mA)
Vertical emittance (XRM) (pm)Horizontal emittance (XRM) (nm)Ib+ Ib- (mA2)

Ib+ Ib- (mA2)
30

The horizontal emittance in the LER depends on HER beam current.

Lsp x1031 (cm-2s-1/mA2)

Horizontal emittance (XRM) (nm)HER beam current changes with
fixed LER beam current to be 340 mA.

LER

HER

IHER / ILER

(ILER = 340 mA)

εyHER

Lsp
beam-beam
blowupεy+LERVertical emittance ismeasured by X-ray
beam size monitor.

Beam-Beam Parameter ξybeam-beam
limit ?

Lsp x1031 (cm-2s-1/mA2)

εy (pm)Collision with small number of bunches（393 bunches）

IHER/ILER (ILER = 340 mA)

HER
ξy+ : 0.0392 / ξy- : 0.0319

Bunch Current Ib (mA)

• The beam current ratio is kept to be ILER : I HER = 5 : 4 (circle)• Beam-beam limit was observed at around 0.03 for HER.
• The bunch current ratio can be optimized to improve luminosity.
• The optimized ratio of beam current is 10 : 7 (triangle) at Ib+ >0.8 mA.
beam-beam
limit ?

<latexit sha1_base64="GJCErN3XGFhCNm0iPoKuYyX6J/w=">AAACnXichVFNaxRBEH0ZNcZVkzVeBA8uLhHxsNQkIR+CEBDBQAj5cLOBTDL0THo3TeaLmd7Fddg/4B/wIAgKIQR/hjl40ZuH/ATxGMGLB2tmJ4QQYqrp7qrX9apfdzmRpxJNdDRgXLl6bfD60I3SzVu3h0fKd0bXkrAdu7Luhl4YrzsikZ4KZF0r7cn1KJbCdzzZcHafZ+eNjowTFQavdDeSm75oBaqpXKEZsssz1mtlp10r8nvPrGYs3HRcxra0HKlFgW89WeilVkv4vrA5rsxna88uV6k2S+bslFk575g1yq2KwpbC8j4sbCOEizZ8SATQ7HsQSHhswAQhYmwTKWMxeyo/l+ihxNw2Z0nOEIzu8triaKNAA46zmknOdvkWj2fMzArG6Acd0DF9pc/0k/5eWCvNa2Raurw7fa6M7JG391b/XMryedfYOWX9V7NGEzO5VsXaoxzJXuH2+Z03745Xn66MpY/oE/1i/R/piL7wC4LOb3dvWa68RylvQP+XK+edkwasjdfMqdrE8mR1brJoxRDu4yEe839PYw4vsYQ63/sBh/iG78YD44WxYCz2U42BgnMXZ8xo/AOE2qEi</latexit>∗L
2ere βy±ξy± =γ ± I±

1.2 x1034 cm-2s-1 at 0.57 mA2 (393 bunches)
4.78 x 1034 cm-2s-1 is expected
for 1565 bunches.
(ILER : 1.4 A / IHER : 1.0 A)

32

Operation Issues

33

LER Collimator
2021

dy (mm) βy (m)εy: 60 pm

June 16

IP

Nsig

D06V1

±2.9

67.3

45.6

D06V2

±2.2

20.6

62.6

D03V1

±8.0

17.0

250.8

D02V1

±1.2

11.9

45.0

dy
Nsig =
σy<latexit sha1_base64="YaEG1i1Qm/f617S5UqW5/OauGgE=">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</latexit>
sha1_base64="vZDcR4+v1rBqnMb2gi7sIMja17k=">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</latexit>
sha1_base64="7eJ/6uyihg698POzJ/IeA1aQVKI=">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</latexit>

injection
point
34

HER Collimator
2021

dy (mm)βy (m)

εy: 45 pm

June 16IP
injection
point

Nsig

D09V1

-1.7

15.5

64.4

D09V2

-3.1

19.4

104.8

D09V3

-1.5

15.5

56.8

D09V4

-3.4

16.7

123.9

D12V1

3.3

16.7

120.2

D12V2

-1.8

15.5

68.2

D12V3

2.1

15.5

79.6

D12V4

-3.2

19.4

108.2

D01V1

±2.2

46.5

48.1
35

History of Speciﬁc Luminosity

HER BxB feedback gain (vertical)
decreased. Swing shift on May 9
HER many aborts(Noise affected BxB FB)

D02V1 collimator
head replacement

2021ab

2nd off-resonance(-60 MeV)
HER
1st off-resonancechange νy(-60 MeV)(43.572 → 43.578)

0.45 - 0.50 mA2
0.40 - 0.45 mA2
0.35 - 0.40 mA2
0.30 - 0.35 mA2
0.25 - 0.30 mA2
0.20 - 0.25 mA2< 0.20 mA236

More detail of Lsp
HERchange νy43.572 → 43.578

HER BxB Feedback gain (vertical) decreased.
Swing shift on May 9
off-resonance (-60 MeV)

3.12x1034

Linac energy FB
troublemaintenance37

May 6, 2021

BxB Feedback Noise in HER
HER BxB FB noise is ﬁxed on June 30
after NIM bin and fanout replacement.

D02V1 replacement
and maintenanceMay 3<latexit sha1_base64="cquYpzb5FH74wQbaf0kcTkUt7F4=">AAACenichVHLSsNAFD2Nr1pfVREEN2JRFKHciKC4Krhxqa1VQSUkcapD0yQkaaGG/oA/4MKVgoj2M9z4Ay76CeJSwY0Lb9OAqKh3mJkzZ+65c2bGcC3pB0SthNLV3dPbl+xPDQwODY+kR8d2fKfqmaJoOpbj7Rm6Lyxpi2IgA0vsuZ7QK4Yldo3yent/tyY8Xzr2dlB3xWFFP7ZlSZp6wJSWnjgoeboZlrTQdqQvGo1wW6OGls5QlqKY/gnUGGQQx6aTvsEBjuDARBUVCNgIGFvQ4XPbhwqCy9whQuY8RjLaF2ggxdoqZwnO0Jkt83jMq/2YtXndrulHapNPsbh7rJzGLD3SLb3QAzXpid5/rRVGNdpe6jwbHa1wtZGzycLbv6oKzwFOPlV/eg5QwmrkVbJ3N2LatzA7+trp+UthLT8bztEVPbP/S2rRPd/Arr2a11sif4EUf4D6/bl/gp2lrEpZdWs5k8vFX5HEFGYwz++9ghw2sIkinxviEndoJt6VGWVBWeykKolYM44voSx/AB50kx0=</latexit>

operation tune

fnoiseT0

Noise

IGPF:HERDV:SRAM:PEAKFREQ2

We operated νy = 43.572 until May 3 and the noise affected BxB FB,
then we got many aborts when we increased the beam current in HER.
The noise moved away from the working point on May 14.

M. Tobiyama

38Vertical Emittance for Single beam in HER on May 6

νy = .580<latexit sha1_base64="FOG/3t78f0sLIiBPwD78+gSFmYo=">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</latexit>

HER bunch current (mA)<latexit sha1_base64="61BEtIICE+vxkYyTx9WWd2uRKlE=">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</latexit>

νy = .585<latexit sha1_base64="3SJVVCCR44r3NWxg+ey9LnbUviY=">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</latexit>

HER bunch current (mA)νy = .575<latexit sha1_base64="vZh+gAw1rDgjAaHdfdhfH54sAdc=">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</latexit>

HER bunch current (mA)

HER bunch current (mA)
Vertical emittance (pm)Vertical emittance (pm)HER bunch current (mA)νy = .570

Vertical emittance (pm)<latexit sha1_base64="KUkCvs3nQ97IvFaGzIWHbX2vINA=">AAACbXichVHLSsNAFD2Nr1pfVREERYrFx6rciFURBNGNS1/VYltKEkcNpklI0kIt/oBrwYUoKIiIn+HGH3DhJ4gLFxXcuPA2DYiKeoeZOXPmnjtnZlTb0F2P6DEkNTQ2NbeEWyNt7R2dXdHung3XKjqaSGmWYTlpVXGFoZsi5emeIdK2I5SCaohNdX+xtr9ZEo6rW+a6V7ZFrqDsmvqOrikeU1tZs5gvzyWSU8l8NE4J8iP2E8gBiCOIZSt6jSy2YUFDEQUImPAYG1DgcstABsFmLocKcw4j3d8XOESEtUXOEpyhMLvP4y6vMgFr8rpW0/XVGp9icHdYGcMIPdANVemebumJ3n+tVfFr1LyUeVbrWmHnu476197+VRV49rD3qfrTs4cdzPhedfZu+0ztFlpdXzo4qa7Nro5URumSntn/BT3SHd/ALL1qVyti9RQR/gD5+3P/BBsTCZkS8spkfH4h+IowBjCMcX7vacxjCctI8bkmjnGG89CL1CcNSkP1VCkUaHrxJaSxD6vxjPw=</latexit>

Vertical emittance (pm)νy = .565

Vertical emittance (pm)Vertical emittance (pm)The noise drives the beam.

νy = .590<latexit sha1_base64="whllxz2dYB+az1MmeBG3+HMY/iw=">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</latexit>

HER bunch current (mA)

HER Vertical Emittance and Vertical Tune

97 bunches

Vertical Emittance (pm)

HER

June 30, 2021

0.825 mA/bunch (80 mA/97 bunches)
0.619 mA/bunch (60 mA/97 bunches)

single beam (no collision)

Vertical Tune
We observed only resonance lines.
There is no strange behavior like May 6
after NIM-bin and fanout module were replaced on June 29.

Tune History: Optics degradation

QCS
initialization

1

maintenance
no QCS initialization

1. 3/28 Magnet PS QC1LE Charging Volt I/L Trouble
2. 4/19 QC1LE quench(4/21 On -> Off-resonance)

2

H. Koiso

3

4

5

6

7

3. 4/26 Off -> On-resonance
4. 5/10 QC1RP & QC1LP quench
5. 5/12 Maintenance
6. 5/14 QC1RP quench
7. 5/23 QC1RP & QC1LP quench

Discrepancy between model and measurement of νy increases rapidly after QCS initialization with optics corrections.
When we skip the QCS initialization, the discrepancy becomes small. QCS coils move slowly or ﬁeld/orbit drifting ?
41

Optics degradation

H. Sugimoto

Optics correction after QCS initialization on March 29, 2021

March 29

April 2∆βx /βx = 5.7 %∆βx /βx = 5.4 %∆βy /βy = 7.9 %∆βy /βy = 24.6 %<latexit sha1_base64="MZER3IuBXuuB/+Rdz8c+sXKjx6A=">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</latexit>
sha1_base64="zhrib+OWJgTHBXevlWF5N3opet8=">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</latexit>
sha1_base64="GD5DXjCRP8PpoCpmn0ZEuRNa7Wg=">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</latexit><latexit sha1_base64="WhctjW/RZ3rjQtGiyGjDjPhSCT0=">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</latexit>
sha1_base64="2ZTk7FPqUBZwtVFttb+rnTpyze8=">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</latexit>
sha1_base64="wF7WiOS0yU85Di11YtlNFToZImY=">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</latexit>

April 2, 2021 (five days after optics correction)<latexit sha1_base64="qamGBGIPwMhRQfP1P6tpuInFHJk=">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</latexit>
sha1_base64="nzzYyh7NY+9BcjNbp+YmVWUoVeE=">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</latexit>
sha1_base64="rtPNiIdGwFB/mf20x3XdU0YGyI8=">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</latexit><latexit sha1_base64="aP8y6AwTcRmHBZIFoVmQExxDtpI=">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</latexit>
sha1_base64="UaSAa/llexGpwPNMcbksu+TUxh0=">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</latexit>
sha1_base64="j/b0wjWoffdvIJJUFZ38fFLES34=">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</latexit>

QC1LP/QC1RP can correct beta-beating.
Correction is ΔK1 ~ 10-4 (1/m).
42

Orbit in the Injection Section in LER
H. Sugimoto

Implementation of BBA in the FUJI section
Leakage vertical dipole fieldfrom Lambertson

before modification of BPM offset
after modification of BPM offset

Lambertson magnet(beam abort system)

Residual dispersions becomes small
in the FUJI section.

before modification of BPM offset
after modification

The vertical emittance did not change so much.

43

2021.06.30 16:48

Harmonic number = 5012

Hor. amp. (ADC)

LER: 600 mA (1565 bunches)
0.383 mA/bunch

injected + stored
bunch (1-bunch)

Leakage Orbit due to Injection Kickers
Large orbit leakage due to injection kickers is observedin the horizontal plane after injection in the LER by using
BOR. Positions of all bunches for 4096 turns are stored.
Problem is that pulse shapes (half sine) are different
among six injection kickers.

kickerleakage orbit

2 μsecabort
gap
βx = 23.3 (m) at BORbunch idThis might be beam loss (BG) at higher beam current andsource of instabilities.

abort
gap

QC2LP (O) : radius = 30 mm
βx = 163 m. Δx= 9.5 mm

xn+1 (mm)Δx (mm)2Jx = 5.56 x 10-7 m# turnsxn (mm)44

Orbit of Injection Beam measured by TBT BPMs in LER
sample-1

βx =24.42 m
Horizontal injection error:

Kicker leakage orbit (stored beam):

2Jx = 1.47x10-6 m

2Jx = 5.56 x 10-7 m

QC2LP (O) : radius = 30 mm
βx = 163 m. Δx= 15.5 mm

QC2LP (O) : radius = 30 mm
βx = 163 m. Δx= 9.5 mm

D06V1 : half width = 6 mm
βx = 14.6 m. Δx= 4.6 mm

D06V1 : half width = 6 mm
βx = 14.6 m. Δx= 2.9 mm# turns
sample-2

sample-3# turns

1/3 of injection error

βx =24.42 m

Oscillation is damped in 250 turns
owing to BxB feed back system.

# turns# turns

45

BPM Position Reading and Displacement Sensor
We noticed the relationship between BPM position reading near sextupole magnets and beam current.
We figured out a sign of the displacement sensors was wrong in the Tsukuba straight section (D1 and D2)for LER and HER. This was since the beginning of SuperKEKB. We confirmed the definition andcorrected a sign of the sensors on April 21, 2021.
The displacement sensor is to correct the relative mechanical movement of BPM for the neighborsextupole magnet.
before modification (SLYTRP1)

after modification (SLYTRP1)

Displacement sensor
BPM position reading
Beam current

H. Sugimoto46

Orbit in the vicinity of the IP
The IP knob uses QK*. Therefore, the orbit is induced by IP knob changes.
Alignment of QKARP and QKALP is difficult.
QKARP

top-view

side-view

LER

2020b

2021b
We adjusted the vertical orbit.

QKDRP

QKBRP

QKARP

QKCLP

QKALP

QKARP

QKDLP

~ 0.4 mm

QKBLP
QKERP

QKCRP

QKELP

QKALP

IP X-Y Couplings/Dispersion Knob and Beta-Beating in the LER
The beta-beating was induced by orbit change due to IP knob ON and OFF in the LER.
Skew quadrupole magnets (QK*) misalignment seems to be source of the beta-beating.
LER IP Knob OFF

SAD
coordinate

H. Sugimoto

LER IP Knob ON

QKARP : H offset = +0.8 mm / V offset = +1.9 mm
QKALP : H offset = -0.8 mm / V offset = +0.2 mm
Large QKARP V offset is consistent with large K0 of BC1RP corrector.

49

Measured beta-beating due to orbit change
May 12 (before)

H. Sugimoto
June 18 (after)

Orbit distortion due to IP knob ON and OFF becomes small after using ZHQC1RP (one of QCS horizontal dipole correctors) .

50

The orbit in the vicinity of IP is reasonable ?
LER

HER

2021b

2021b
H-angle induces
horizontal dispersion.
H-angle at the IP
is determined toreduce SR on PXD.

How to determine
H-angle at the IP ?
Detector BG ?

V-angle at the IP shouldbe optimized by luminosity.

QCS BPMs

V-angle at IP is determined
to reduce SR heating.

QCS BPMs

Horizontal Angle at the IP and Horizontal Dispersions in the HER

H. Sugimoto
150 µradHorizontal angle at the IP is 690 µrad to reduce SR background on PXD.
Horizontal dispersions induced by the orbit are corrected in the Tsukuba section
by using quadrupole magnets near the LCC sextupoles.

90

290

490

690

The optimized horizontal angle is 150 µrad at the IP.
The rms residual dispersion will reduce from 33 mm to 14 mm.
The residual dispersion at the LCC sextupole is also reduced.

52

Continuous Orbit Correction
We changed the horizontal orbit correction algorithm.
The integrated horizontal kick angle was not constant sufficiently before 2021a due to poor accuracy of convergence. So we modified thealgorithm to guarantee the constant value for the total horizontal kick angle.
(We had minor bug at the beginning of 2021ab, we fixed the bug.)
2020b

LER

2021b

No data53

The momentum deviation becomes almost constant.

2020b

HER

2021b

No data54

Operation Statistics

Maintenance day is every two weeks.
Maintenance is usually until 17:00, the injection tuning
for SuperKEKB starts following PF and PF-AR.
Startup with stable operation of injector linac is a key
to resume SuperKEKB as quickly as possible.

We developed a resumption strategy to reduce machine tuning
at a startup after maintenance.

55

QCS Quench
andCollimator Damage
56

QCS Quench List (except for earthquake and PS trouble)

4/19 (MO) Owl

5/10 (MO) Day

5/14 (FR) Owl

5/23 (SU) Owl

5/28 (FR) Owl

1:07

14:26

0:35

8:24

3:21

57

HER QC1LE

LER: 836 mA / HER: 819 mA
HER D09V1 damaged

LER QC1LP, QC1RP

LER: 906 mA / HER: 726 mALER D02V1 damaged

LER QC1RP

LER: 837 mA / HER: 679 mA
LER kicker misfire

LER QC1LP, QC1RP

LER: 836 mA / HER: 678 mA
LER D06V1 damaged

LER QC1RP

LER: 834 mA / HER: 677 mALER D06V1 damaged

6/2 (WE) Swing

20:13

LER QC1LP, QC1RP

LER: 840 mA / HER: 678 mA
LER D02V1 damaged

6/6 (SU) Day

16:06

LER QC1LP, QC1RP

LER: 838 mA / HER: 677 mA

LER and HER Abnormal Beam Abort
835 mALER

one turn

H. Nakayama

typical samples

709 mA

Beam dose at
IP beam pipe

HER

TBT orbit measurement4096 turns for every bunches

one turn

Horizontal orbit
vertical orbit
beam
abort
beam loss

beam
abort
bunch current• No orbit oscillation• Very fast beam loss
within a few turns

beam loss

58

Beam Abort due to Injection Beam
835 mA (1272 bunches)

kicker leakage orbit

Injected beam was lost partially.

Orbit in beam transport line
Energy deviation was large.

H. Nakayama
H. Kaji59

Movable collimator to reduce beam background
Damage due to beam loss

S. Terui
T. Ishibashi
Y. Suetsugu

Vertical collimator: D02V1 (LER)
tantalum (Ta) head with 10 mm long tip

beam

TOP

Horizontal collimator: D06H3(LER)
tungsten (W)beam
BOTTOM
June 8, 2021

Stored beams hit the collimator head
due to misfire of injection kicker.
60Summary of Machine Operation
1. Difficulties of increasing beam currents
Abnormal beam abort with beam loss; no oscillation, very fast beam loss within a few turns. Damaged collimator headenhances the aborts ?
Collimator aperture (physical aperture: PA) is narrow which is smaller than dynamic aperture (DA).
Short lifetime in the LER; Crab waist reduces DA. However, the aperture in the LER is PA = DA.
Lower "TMCI" threshold; 0.9 mA/bunch, large tune shift of single bunch ~0.013 > half of synchrotron tune in the LER
Synchro-beta resonance structure; good working area is small. Luminosity and DA is compatible ?
Injection kicker leakage orbit in the LER; It becomes a source of instabilities. Beam loss is proportional to stored beam
current. We measured the beam loss owing to orbit oscillation using BOR.
BxB FB in the HER; noise effect (fixed) and feedback gain, feedback gain and luminosity.
Stabilities of linac injector; Many types of feedback system should work sufficiently. Stability of injection system; septum
and kickers, especially HER septum behavior.
2. Beam-beam blowup
Effect of chromatic X-Y couplings is still unclear or IP knob is not sufficient. Rotating sextupoles in LER is effective.
Beam current ratio between LER and HER affects flip-flop of the beam size.
We prepare βx* = 60 mm lattice in LER (current βx* : 80 mm) to cure BBHT(XZ) if necessary.
3. Beta squeezing (not performed in 2021ab)
Down to 0.8 - 0.6 mm is necessary to improve luminosity. Training process is needed. (It takes time; see βy* = 1 mm)
61