code development and polarized beam simulation...

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IAS HEP Conference, HKUST Mini-workshop on Accelerator, Jan. 18-19, 2019 Code Development and Polarized Beam Simulation Studies Franc ¸ois M ´ eot Collider-Accelerator Department Brookhaven National Laboratory Contents 1 ZGOUBI 2 2 Hadron polarization at RHIC complex 7 3 Electron polarization in eRHIC 16 4 Hadron polarization in eRHIC 20 5 JLEIC EIC 23 6 Cornell-BNL CBETA FFAG ERL 25

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  • IAS HEP Conference, HKUST

    Mini-workshop on Accelerator, Jan. 18-19, 2019

    Code Development and PolarizedBeam Simulation Studies

    François Méot

    Collider-Accelerator Department

    Brookhaven National Laboratory

    Contents

    1 ZGOUBI 2

    2 Hadron polarization at RHIC complex 7

    3 Electron polarization in eRHIC 16

    4 Hadron polarization in eRHIC 20

    5 JLEIC EIC 23

    6 Cornell-BNL CBETA FFAG ERL 25

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    21 ZGOUBI

    • SEEN FROM SPACE

    https://sourceforge.net/projects/zgoubi/files/stats/map

    ⋄ Zgoubi was first written in 1972... 45+yrs !

    ⋄ Installed in sourceforge in 2007

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    3https://sourceforge.net/projects/zgoubi/files/stats/timeline

    ⋄ China seems poised to catch up !

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    4• A DOE FUNDED SBIR (2018-2020)

    ⋄ [1] Dan Abell (Radiasoft) et als., “Zgoubi Status: Improved Performance, Features,and Graphical”, IPAC 19, Melbourne.

    ⋄ This includes development of a graphical interface under SIREPO (Paul Moeller/Ra-diasoft)

    Ref.: https://beta.SIREPO.com/#/accel

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    5• ZGOUBI NUMERICAL INTEGRATOR

    ⋄What needs be solved:

    d(mṽ)dt

    = q ṽ × b̃

    dS̃dt

    =qm S̃× ω̃

    (

    ω̃ = (1 + γG)b̃ +G(1− γ)b̃//

    )

    G : gyromagnetic factor, γ : Lorentz relativistic factor,

    c : velocity of light, q : charge, m :mass.

    u (M1)

    M1

    R (M 1

    )

    u (M0

    )

    R (M

    0)

    z

    x

    y

    Z

    Y

    X

    M

    0

    Reference

    ⋄ ODE slver: Taylor series in the step size ∆s:

    ã(M1) ≈ ã(M0) +dã

    ds(M0)∆s + ... +

    dnã

    dsn(M0)

    ∆sn

    n!(1)

    - Solving particle motion : ã stands for position R̃ or velocity ṽ.

    - Solving spin motion : ã stands for the spin S̃

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    6

    •A note in passing: Zgoubi is as good at accelerating in a cyclotron ...

    ⋄ 184 inch cyclotron at

    Berkeley, 100MeV/u ions

    (1940s)

    ⋄ Double-Dee acceleration to 10 MeV in 50 turns.Accuracy on time computation is critical:

    -100

    -80

    -60

    -40

    -20

    0

    20

    40

    60

    80

    100

    -100-80-60-40-20 0 20 40 60 80 100

    R sin

    θ [cm]

    R cos θ [cm]

    -0.08

    -0.06

    -0.04

    -0.02

    0

    0.02

    0.04

    0.06

    0.08

    0.1

    0.12

    0 0.5 1 1.5 2 2.5 3 3.5 4

    ∆W [M

    eV]

    RF phase [rad]

    starting point (φ =π/2)0__

    synchronism at one point(f = f ) rf rev

    |

    ∆φ0

    [cosφ](W) = cosφ0 + π[

    1− ωRFωrev0(1 + W

    2m0c2)]

    W

    qV̂

    • ... as it is at tracking polarization in large colliders... Let’s see that!

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    72 Hadron polarization at RHIC complex

    • Polarized beam simulations in RHIC complex using Zgoubi- include p, He3

    - start at the booster, and include AGS, AtR, RHIC

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    8• Booster

    ⋄ Zgoubi simulations support the eRHIC polarized 3He project

    ⋄ AC dipole & tune kickerat booster E3 straight:

    ⋄ fosc ≈ 250 kHz

    ⋄ This year:- Will establish crossing Gγ = 0 + Qy(Qy ≈ 4.2) with polarized protons .- Spin dynamics conditions similar to 3He

    crossing 12−Qy for eRHIC.

    Refs.: K. Hock et als., BNL C-AD,https://public.bnl.gov/docs/cad/Documents/Overcoming%20proton%20and%203He%20intrinsic%20resonances%20in%20the%20AGS%20Booster%20with%20an%20ac%20dipole.pdf;https://public.bnl.gov/docs/cad/Documents/Intrinsic%20resonances%20and%20AC-dipole%20simulation%20of%203He%20in%20the%20AGS-Booster.pdf.

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    9• AGS (1): On-line AGS acceleration cycle model

    ⋄ Zgoubi is one of the two engines of the on-line model of the AGS (other is MADX).

    It uses the 3-D OPERA field maps of the helical snakes

    The 240 main dipoles in the AGS may also be represented by their measured field maps.

    ⋄ Full polarized proton bunch acceleration cycles in the AGS are routinely simulated : thousands

    of particles, 150000 turns. (on NERSC at the moment, plans for GPU platforms [V. Ranjbar])

    5 10 15 20 25 30 35 40 45

    -.003

    -.002

    -.001

    0.0

    0.001

    0.002

    0.003

    0.004

    x, z (m) vs. G γ

    H: red V: blue

    Particle excursion over full AGS cycle.

    8.7

    8.75

    8.8

    8.85

    8.9

    8.95

    9

    5 10 15 20 25 30 35 40 45

    Tun

    es

    Energy (Gγ)

    Qy ZgoubiQz Zgoubi

    Qy MeasuredQz Measured

    Tunes, measured and modelled.

    ⋄ Optimization of AGS parameter settings routinely basedon Zgoubi simulations.

    [Y. Dutheil, BNL C-AD, PhD dissertation, April 2015].

    0.72

    0.74

    0.76

    0.78

    0.8

    0.82

    5 10 15 20 25 30 35 40 45

    Ave

    rage

    bea

    m p

    olar

    izat

    ion

    (<S>

    ⋅n0)

    Energy (Gγ)

    Without tune jumpsWith tune jumps

    Evolution of the polarization along AGS acceleration cycle,

    103 particles, 6-D bunch.

    Loss at Gγ ∼ 5 (a pair of weak vertical intrinsic resonances)and at Gγ = 36 +Qy in the present hypotheses.

    Ref.: Y. Dutheil, BNL C-AD, PhD dissertation,https://public.bnl.gov/docs/cad/Documents/Spin%20dynamics%20modeling%20in%20the%20AGS%20based%20on%20a%20stepwise%20ray-tracing%20method.pdf.

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    • AGS (2): Polarization profiles

    ⋄ Simulating the AGS acceleration cycle provides guidance through thesubtleties of the manipulation of polarization, for optimized transmission

    Yann Dutheil

    (PhD dissertation, 08/2015)

    Polarization profile R =σPσl

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    • RHIC ring (1)

    ⋄ Zgoubi has been used over the past 10 years to study polarization inRHIC.

    ⋄ A benchmarking example: crossing the strong snake resonance Gγ =393 +Qy

    ⋄ Theory: < Sy >= 1−

    8|ǫ|2

    λ2 sin2 πλNs(1− |ǫ|

    2

    λ2 sin2 πλNs)

    λ =√

    δ2 + |ǫ|2

    δ = GγR −Gγ -1-0.9

    -0.8

    -0.7

    -0.6

    -0.5

    -0.4

    -0.3

    410 415 420 425 430 435 440 445

    <Sy>

    G.gamma

    Zgoubi tracking (Nov. 2011)

    1000 prtcls2000 prtcls

    Model

    ⋄ Routinely studies include sensitivity to defects (e.g., spin rotation anglein snakes or in rotators), studies accompanying RHIC runs, optimization

    of the AtR beam line, etc.

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    • RHIC (2): A full acceleration cycle to 100 GeV×100 GeV pp physics

    ⋄ A 1 million turn tracking⋄ Goal: comparison of polarization transport with two different optics:

    - a new, Run 15 optics- earlier Run 13 optics

    8 particles on 10 rms invariants are plotted.Envelopes (blue) are from theory [SYL].

    30 40 50 60 70 80 90-1.

    -.8

    -.6

    -.4

    -.2

    0.0

    0.2

    0.4

    0.6Zgoubi|Zpop 20-04-2015 S_y .vs. Kinetic E (GeV)

    93-

    69+

    75+

    81+174-

    30 50 70 90-1.

    -.8

    -.6

    -.4

    -.2

    0.0

    0.2

    0.4

    Zgoubi|Zpop 29-04-2015 S_y vs. kinetic E (GeV)

    93- 69+

    75+

    150+

    Normalized invariants over 500,000 turns :

    2.38

    2.4

    2.42

    2.44

    2.46

    2.48

    2.5

    2.52

    2.54

    2.56

    2.58

    0 100 200 300 400 500 600 2.4

    2.42

    2.44

    2.46

    2.48

    2.5

    2.52

    2.54

    2.56

    2.58 26 28 30 32 34 36 38 40

    βγεx (

    µm)

    βγεy (

    µm)

    TURN (103)

    E (GeV)

    βγεxβγεy

    x×√

    (p/p0) and y ×√

    (p/p0)

    over 2 million turns :

    3.E+4

    4.E+4

    5.E+4

    6.E+4

    7.E+4

    8.E+4

    -.003

    -.002

    -.001

    0.0

    0.001

    0.002

    0.003

    Zgoubi|Zpop 20-04-2015 norm. x (m) vs. KinEnr (MeV)

    3.E+4

    4.E+4

    5.E+4

    6.E+4

    7.E+4

    8.E+4

    -.004

    -.002

    0.0

    0.002

    0.004

    0.006

    Zgoubi|Zpop 20-04-2015 norm. y (m) vs. KinEnr (MeV)

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    • RHIC (3): Re-visiting RHIC snakes

    Everything You Always Wanted to Know About Snakes (But Were Afraid to Ask)

    Ref.: F. Méot, Re-visiting RHIC snakes: OPERA fields, ñ0 dance, C-A/AP/590, https://public.bnl.gov/docs/cad/Documents/Re-visiting%20RHIC%20snakes%20OPERA%20fields%20n0%20dance.pdf

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    • Theory: particle coordinates across the helical dipole satisfy:

    x = x0 +B0

    k2Bρ[cos(ks + α)− cos(α)] +

    [

    x′0 +B0kBρ sin(α)

    ]

    s

    y = y0 +B0

    k2Bρ[sin(ks + α)− sin(α)] +

    [

    y′0 −B0kBρ cos(α)

    ]

    s

    α=0−→

    {

    x = x0 +B0

    k2Bρ[cos(ks)− 1] + x′0s

    y = y0 +B0

    k2Bρsin(ks) +

    [

    y′0 −B0kBρ

    ]

    s

    ⋄ x0, , x′0, y0, y

    ′0 the initial coordinates (taken wrt snake axis),

    ⋄ α the angle of the field to the vertical at entrance,

    ⋄ k = pitch = 2π/L = 2.61800, length L = 2.4 m.

    µφS

    S

    • From a field map model (i.e., field map of a 10.4 meter, 4-module RHIC snake) :

    -0.02

    -0.015

    -0.01

    -0.005

    0

    0.005

    0.01

    0.015

    0.02

    0.025

    0.03

    0 1 2 3 4 5 6-0.02

    -0.015

    -0.01

    -0.005

    0

    0.005

    0.01

    0.015

    0.02

    0.025

    0.03 0 1 2 3 4 5 6

    x, y [m]

    z [m]

    Half-RHIC snake, trajectories

    x, th.track

    y, th.track

    x and y vs. distance

    at injection energy, half the snake

    (5.2 meter).

    -2

    -1

    0

    1

    2

    -2 -1 0 1 2

    y (cm)

    x (cm)

    RHIC snakes: projected helix

    300250

    theor. " 100

    22.9theor. "

    Non-circular, (x,y) projection ,

    theory and numerical,

    23, 100, 250, 300 GeV.

    0 2 4 6 8 10 12

    -.8

    -.6

    -.4

    -.2

    0.0

    0.2

    0.4

    0.6

    0.8

    1.Zgoubi|Zpop 13-12-2016

    Sx

    Sy

    Sz

    Sx, S_y, S_z vs. s (m)

    Spin components along orbits .

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    • RHIC (4): Spin flipper

    ⋄ Sweep Qosc through Qs =12

    +:

    a matter of a 104 ∼ 5 × 105 turn trackingaround RHIC

    ⋄ AC-dipole + DC-rotator assembly excites asingle, isolated resonance, at Qs = Qosc.

    ACD bump 1 ACD bump 2

    DC bump

    1 2 3 41 2 3 4 5

    Spin flip efficiency vs. crossing speed :Very good accord obtained between

    measurements and numerical simulations

    -100

    -98

    -96

    -94

    -92

    -90

    -88

    -86

    50000 100000 150000 200000 250000

    0.5 1 1.5 2 2.5 3 3.5

    Pf/Pi[%]

    τX [turn]

    τX [sec]

    APEX (∆D’=3.45)fit

    Y, ∆D’=3.45fit

    ∆D’=3fit

    ∆D’=0fit

    Image at 1−Qs is not excited:

    Frequency mis-match of ACD1-3 (or

    ACD3-5) oscillator excites Qs = 1−1

    2

    +:

    0 10000 20000 30000 40000 50000

    turn

    0.492

    0.494

    0.496

    0.498

    0.500

    0.502

    0.504

    0.506

    0.508

    ν osc,ν s

    −1.0

    −0.5

    0.0

    0.5

    1.0

    Sy

    Multiple crossing:

    δνs =1 +Gγ

    π∆D′

    ∆p

    p

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    3 Electron polarization in eRHIC

    Studies in eRHIC include SR induced spin diffusion :

    SPIN DYNAMICS

    +STOCHASTIC ENERGY LOSS BY SR

    =⇒ SPIN DIFFUSION, FOR FREE !

    Ref.: eRHIC pCDR, BNL C-AD (2018), to be published.

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    • eRHIC (1): Monte Carlo SR benchmarked in the late 1990s

    ⋄ Thousands of particles, tracked over tens of thousands of turns

    0 10 20 30 40 500

    5

    10

    15

    20

    25

    30

    35

    BETA-LNS v5.10 /01/10/99/ 17-Jun-10 11:11:40 1st 0.000E+00OPTICAL FUNCTIONS (m) VERSUS S (m)

    Qx = 36.200Qy = 11.200 betX

    betY

    Dx

    Chasman-Green ESRF cell.

    Benchmarking virtue : provides

    analytical formulas for damping

    times, emittance damping, etc.

    ⋄ Coupled lattice. 2000 particles,20,000 turns. 6 GeV ←−

    Good agreement withǫyǫx =

    |κ|2

    |κ|2 +∆2/2and with ǫx + ǫy = ǫ0

    1e-05

    0.0001

    0.001

    0 1000 2000 3000 4000 5000

    εl (eV.s)

    turn

    18 GeV

    12 GeV

    9 GeV

    6 GeV

    Longitudinal damping, 6, 9, 12 and 18 GeV.

    Excellent match with expected ǫl,eq =αEsΩs

    Cqγ2

    Jl ρ.

    0

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    0.7

    0.8

    0.9

    1

    0.01 0.1 1 10 0.8

    0.85

    0.9

    0.95

    1

    1.05

    1.1

    1.15

    1.2

    ε y/ε

    x

    (εx+

    ε y)/

    ε x,0

    |κ| / ∆

    ratiofit

    invariantfit

    Ref.: F. Méot, Simulation of radiation damping in rings, using stepwise ray-tracing methods, 2015 JINST 10

    T06006.

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    • eRHIC (2.1): Polarization lifetime in eRHIC storage ring

    • Typically:

    As produced using SITROS at DESY

    [J. Kewisch, DESY Rep. 83-032, 1983]

    (i) track particles and spins, including Monte

    Carlo SR,

    (ii) produce polarization landscape,

    i.e., Peq versus ring rigidity setting (aγ units,here):

    • Spins tracked over 240 damping

    times in eRHIC, 18 GeV

    0.99

    0.992

    0.994

    0.996

    0.998

    1

    40.5 40.55 40.6 40.65 40.7 40.75 40.8 40.85

    Sl

    Polarization, eRHIC e-storage ring, 18 GeV From polSpectrumFromFai.out

    240τSR 23τSR

    • Polarization decay with time:

    The diffusion time constant τDis obtained from linear regression

    P/P0 = exp(−t/τD) ≈ 1− t/τD.

    Then, Peq stems from

    Peq = PST × τeq/τST ,

    given that τeq = (1/τST + 1/τD)−1.

    0.9992

    0.9993

    0.9994

    0.9995

    0.9996

    0.9997

    0.9998

    0.9999

    0 20 40 60 80 100 120 140

    0

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    0.7

    0.8

    0.9 0×100 1×108 2×108 3×108 4×108 5×108 6×108 7×108 8×108

    <Sl> zoom

    <Sl> eq.

    τ [×103 turn]

    Polarization vs. time at store, 18 GeV

    τ [turn]

    x1-y1: 40.66, 63 min.x1-y1: 40.615, 48 min.x1-y1: 40.705, 46 min.

    x2y2: e-t/τEq

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    • eRHIC (2.2): An ergodic approach to electron spin diffusion

    0.9

    0.91

    0.92

    0.93

    0.94

    0.95

    0.96

    0.97

    0.98

    0.99

    1

    0 50 100 150 200 250 300 350 400 450

    S y

    turn [x103]

    Sy vs. turn#, from zgoubi.fai. gnuplotfaiSy.vs.Turn.eps

    0.9984

    0.9986

    0.9988

    0.999

    0.9992

    0.9994

    0.9996

    0.9998

    1

    0 50 100 150 200 250 300 350 400 450

    <Sl>

    τ [103 turn]

    Polarization vs. time at store, 18 GeV From TBTAverage.out. 2048 folders.

    P0 = 0.9999

    τD = 76.5708

    trackedfit

    Stochastic spin motion observed at IP, single particle. A linear regression on

    P/P0 = exp(−tτD) ≈ 1− tτD provides the diffusion time constant τD.

    10-4

    10-2

    100

    102

    104

    39.8 40 40.2 40.4 40.6 40.8 41 41.2

    τ D [min.]

    aγref

    τD, eRHIC e-storage ring, 18 GeV RunXXX/zgoubi.fai | TBTLinRegTauFromRun.FaiFiles

    39.8 < aγref < 41.2

    40k 80k 450k

    An energy scan of the diffusion time

    constant provides the diffusion landscape.

    0.001

    0.01

    0.1

    1

    10

    100

    1000

    39.8 40 40.2 40.4 40.6 40.8 41 41.2

    τ D [min.]

    aγref

    τD, eRHIC e-storage ring, 18 GeV RunXXX/zgoubi.fai | TBTLinRegTauFromRun.FaiFiles

    39.8 < aγref < 41.2

    40 bins, 0.5xbeam aσE80 bins, full aσE

    120 bins, 1.5xbeam aσE

    Sliding average of the diffusion time

    constant over the energy scan.

    Ref.: F. Méot, An ergodic approach to polarization in eRHIC electron storage ring,https://public.bnl.gov/docs/cad/Documents/An%20ergodic%20approach%20to%20polarization%20in%20eRHIC%20electron%20storage%20ring.pdf

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    4 Hadron polarization in eRHIC

    • Studies in eRHIC include im-proving proton polarization: 70%

    up to 275 GeV, using 6 snakes.

    Today, with 2 snakes: close to 60%

    at best, top energy is 255 GeV.

    • And 3He polarization to 70%,also requiring 6 snakes.

    Ref.: eRHIC pCDR, BNL C-AD (2018), to be published.

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    • 3He in AGS⋄ AGS with 3He : G= −4.18. AGS partial snakes are 2.3

    times stronger than for protons (14% and 25%).

    ⋄This is ok for overcoming 1.5 times stronger resonances.

    ⋄ Issue here : snakes induce

    ~n0 tilt resulting in harmful

    81 resonance series Gγ =

    int. ± Qx, stronger with

    3He.

    ⋄ A possibility : stronger cold snake/wider spin tune gap

    to put both Qx,Qy in the gap

    ⋄Proof-of-principle simulation :

    a 2000-3He bunch in 15π µm emittance :

    ⋄With 3He, snakes are |G3He|/Gp=2.3 timesstronger than for protons :

    ⋄ At identical normalized emittance,strengths of intrinsic resonances satisfy

    |ǫ3He||ǫp|

    =

    |G3He|Gp

    ≈ 1.5

    0

    0.005

    0.01

    0.015

    0.02

    0.025

    0.03

    0.035

    0.04

    0.045

    5 10 15 20 25 30 35 40 45

    |ε| (10

    π µm)

    AGS, RESONANCE STRENGTHS, INTRINSIC

    3Heproton

    ⋄Qx and Qy in spin gap⇒ Gγ = int.±Qx,y never happens :

    -1

    -0.5

    0

    0.5

    1

    32 34 36 38 40 42 44 0.5

    0.6

    0.7

    0.8

    0.9

    1

    n 0,y

    frac([1-] Q s), Q x, Q

    y

    G g

    Qx Qy n0,y Qs

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    • RHIC with 6 Snakes

    ⋄ Polarization goal at store, 42∼275 GeV : 70%

    ⋄ RHIC Blue and Yellow rings today reach 60% polar-

    ization in 255 GeV proton runs, with 2 snakes per ring.

    ⋄ Stronger 3He resonance strength (×1.5) require more

    snakes.

    ⋄ Foreseen scheme :

    - 6 snakes ensure Nsnakes > 5|ǫint|max ≈ 4,

    - 2π/6 distance ensures energy-independent Qs,

    - snake axes at φk = ±45o yield Qs =

    6

    k=1(−)kφk = 3/2

    - build 4 additional snakes from existing, like-helicity, ro-

    tator modules

    A glimpse on snake resonance crossing simulations,

    411-Qy and 393+Qy

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    5 JLEIC EIC

    Ref.: F. Lin, JLEIC Ion and Electron Polarization, EIC collaboration meeting, JLab, Oct. 2018

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    JLEIC EIC

    Ref.: V. Morozov, Spin Transparency Study and Test at RHIC, ibidem

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    6 Cornell-BNL CBETA FFAG ERL

    Exclusive use of OPERA maps to model the 4-pass ERL in Zgoubi⋄ 6 MeV injection, 36 MeV linac

    ⋄ 4 energies reciculated: 42, 78, 114 and 150 MeV

    CBETA commissioning starts in March 2019

    ⋄ Zgoubi model in prepara-

    tion. Will be used for off-

    line studies during CBETA

    commissioning.

    ⋄ On the other hand, Cor-

    nell Wilson Lab has a polar-

    ized electron source in de-

    velopment.

    ⋄ There is plans to install

    as CBETA source. An op-

    portunity tp perform spin

    transport studies.

    Ref.: F. Méot, Procs ICAP 18 Conference, Key West, USA.

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    26

    THANK YOU FOR YOUR ATTENTION

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    BACKUP SLIDES

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    Cyclotron data file

    USING A FIELD MAP

    Uniform field sector’OBJET’64.62444403717985 ! Rigidity2 ! Generate a1 1 ! single particle.4.087013 0. 0. 0. 0. 0.3162126 ’o’1

    ’TOSCA’0 21. 1. 1. 1.HEADER_8315 151 1 22.1 1.geneSectorMap_180deg.out0 0 0 021.20. 0. 0. 0.

    ’CAVITE’30. 0.100e3 1.57079632679

    ’REBELOTE’60 1.1 99

    ’SYSTEM’6cp gnuplot_zgoubi.plt.cmd temp.cmdsed -i ’s@pause 2@pause 0@g’ temp.cmdgnuplot < temp.cmdokular gnuplot_zgoubi.plt_XYLab.eps &rm -f temp.cmd

    ’END’

    USING ZGOUBI’s ANALYTICAL FIELD MODEL

    ’OBJET’64.6244440371798521 14.087013 0. 0. 0. 0. 0.3162126 ’o’1

    ’DIPOLE’2120. 50.60. 9.1475315 -1. 0. 0.10. 0.4 .1455 2.2670 -.6395 1.1558 0. 0. 0.+30. -30. 1.E6 -1.E6 1.E6 1.E610. 0.4 .1455 2.2670 -.6395 1.1558 0. 0. 0.-30. +30. 1.E6 -1.E6 1.E6 1.E60. 0.0 0. 0. 0. 0. 0. 0. 0.0. 0. 1.E6 -1.E6 1.E6 1.E6 0.2 20..22 43.879742 0. 43.879742 0.

    ’CAVITE’30. 0.100e3 1.57079632679

    ’REBELOTE’60 1.1 99