Beam MC progresses

for beam MC sub-group

Summary of update in 09b,c,10a09b• Geometry of baffle, target, 1st horn, dump and MUMON is updated.

09c• MUMON structures were included. • Energy deposit in the MUMON detector can be stored. • Emittance and Twiss parameters via card.

10a to be released soon• Horn2&3 geometry update• Mag. field inside inner conductor• Store primary proton vector information to enable weighting method• New ND280 flux algorithm• Store particle interaction history• K±µ3 and K0µ3 decay for neutrino• Random number generation seeds control

Comparison among different versionsK. Matsuoka

T2K horn effect (jnubeam 09c)

X9.4 x16

On-axis Off-axis

A.K.Ichikawa

Horn Magnetic FieldHow should we treat the magnetic field inside the inner

conductor? Horn1 inner conductor

Inner radius = 2.7cm, outer radius=3cm

Assuming that the elec. current is uniform in the conductor, (skin depth > 5mm)

Significant effect on MUMON signal was foundModest effect on neutrino flux

K. Matsuoka

)(

)(

2 22

220

ab

ar

r

IB

r

B

Inner conductor

Realistic. B-field

2D Gaussian fit Peak flux (/cm2)* x (cm) y (cm)

Max. B-field (8.74±0.03) x 107 96.4±0.8 98.7±0.9

Realistic B-field (8.09±0.03) x 107 99.0±0.9 102.1±1.0

Min. B-field (7.41±0.03) x 107 102.4±1.0 104.7±1.0

0 kA (1.48±0.02) x 107 156±11 154±10

(* per 3.3 x 1014 POT)

8~9% effect. (difference from realistic B field)

mag. field inside inner conductor-MUMON, all horns on-

Max. B-field 1/r-shape field starts from inner surface of the inner conductor

Min. B-field starts from the outer surface of the inner condcutor

mag. field inside inner conductor E spectra (SK)

Red: Max.Black: RealisticBlue: Min.

Red: Max./realisticBlue: Min./realistic

<3% effect (need more statistics)

All

mag. field inside inner conductor E spectra (ND on-axis)

(Error bars may be under-estimated.See later slides.)

All

Red: Max.Black: RealisticBlue: Min.

Red: Max./realisticBlue: Min./realistic

mag. field inside inner conductor INGRID profile

All

Red: Max.Black: RealisticBlue: Min.

All

Red: Max.Black: RealisticBlue: Min.

abs(x) ≤ 5.5 m && abs(y) ≤ 0.5 m

ND2 ND2

abs(x) ≤ 0.5 m && abs(y) ≤ 5.5 m

Due to the magnetic field in the inner conductors, flux at ND on the axis gets sharper than that of 09c (min B-field).•Peak value: (min) 5.66 x 1017 (realistic) 5.79 x 1017 /m2/1021 POT

Horn2 and Horn3 Geometry updateupdate from conceptual shape to real shape• Horn2

– outer conductor radius : 40 cm -> 49.048 cm– B-field region (Z-length) : 200 cm ->199.7 cm

• Horn3– outer conductor radius : 70 cm 65.5 cm

H.Kubo

http://jnusrv01.kek.jp/Indico/getFile.py/access?contribId=0&resId=0&materialId=slides&confId=147

Horn2&3 geometry updatemuon flux @mumon (Si-plane, horn 320kA)

• flux decreased by 3%, profile shape is same

muon peak flux (cm-2) sigma X [cm] sigma Y [cm]

09b 7.2 x 10 4 101 ± 1 104 ± 1

new horn geom. 6.9 x 10 4 102 ± 1 105 ± 1

3horns, 320kA @3.4x1011POT

Horn2&3 geometry updateneutrino flux

09bnew

@SK

Far/Near

less than 5% difference upto 5GeV

Parents of muons in muon pit-pions-

H.Kubo. K.Matsuoka

Horn off

1st Horn 273kA

All horns 320kA

Parents of muons in muon pit-kaons-

H.Kubo. K.Matsuoka

Horn off

1st Horn 273kA

All horns 320kA

Parents of muons in muon pit-K/pi ratio-

entries (/5x10^7 POT) Ratio (K / Pi)

horn current pion (+/-)

K(all) K0 K+ K- K(all) K0 K+ K-

0kA 64981 5441 172 4548 721 0.084 0.003 0.070 0.011

273kA , 1st horn only

101623 8327 189 7466 672 0.082 0.002 0.073 0.007

320kA , 3horns 259030 15861 206 15157 498 0.061 0.001 0.059 0.002

Proton information• Store primary beam information• Accumulate POT w/ a flat proton beam and weight t

w/ an arbitrary proton profile to simulate that profile• No need to make many MC data sets of various proton

beam profile.

K. Matsuoka

x (mm) x (mm) Peak flux (/cm2)* x (cm) y (cm) x (cm) y (cm)

Weight 0 3.6 (2.81±0.02) x 104 1.0±1.0 0.9±0.7 137±4 129±3

Normal 0 3.6 (2.84±0.02) x 104 1.6±1.1 1.7±1.1 133±4 132±4

Weight 5 3.6 (2.84±0.02) x 104 –4.3±1.6 0.9±0.9 169±6 128±3

Normal 5 3.6 (2.87±0.02) x 104 –7.9±1.7 1.8±1.0 162±6 128±3

Weight 5 1.7 (2.82±0.02) x 104 –11.8±2.4 0.9±1.3 166±9 128±4

Normal 5 1.7 (2.83±0.02) x 104 –8.9±1.6 0.8±1.1 154±5 132±4

Demonstration w/ MUMON profile

y: 1.7 mm(* +–/3.4 x 1011 POT)

Production history• Fill ntuples with neutrino history, taking

decay chains into account. – information of primary, secondary,...

interactions)

• Include additional decay modes for pions and kaons, updated branching ratios– π± → e± νe

– K±µ3 and K0µ3 – neglect K0S semileptonic decays ? (e.g. K2K

case)

N. Abgrall

http://jnusrv01.kek.jp/Indico/getFile.py/access?contribId=4&resId=0&materialId=slides&confId=133

new ND flux calculation algorithm• current filling routine

– SK : treated as a “point”. for every decay of /K/, neutrino is forced to go towards SK probability is calculated and stored as “norm”.

– ND : repeat parent’s decay randomly (uniformly in CM) by 1,000 times

only neutrinos which have proper angle are filled.

• New method : same method as SK case.1. choose a detection point (x, y) randomly in the ND plane2. calculate weight (acceptance) for this direction

• Motivation– In the current version, high-energy pions are multiply

used. Events are not independent. Simple error couting results in underestimate.

H.Kubo

http://jnusrv01.kek.jp/Indico/getFile.py/access?contribId=0&resId=0&materialId=slides&confId=162

Enu

• spectrum seems to be consistent• χ2 = 19.7 / 39

– to small– due to using same set of parents ?

error histogram (Enu)

• low energy (< 1GeV) : same or smaller error• Original method had been giving underestimated error

originalnew

on-axis xnu (fitting)

• fit with Gaussian– large chi2 & mean offset (10 sigma) in original algorism

indicates under estimation of error

original new

χ2 / ndf 867 / 17 21.0 / 17

mean -1.57 ± 0.16 cm -2.0 ± 3.5 cm

sigma 568 ± 0.4 cm 556 ± 8 cm

original new

Other activity• Detailed check of dimensions by P.Perio• Treatment of Random numbers

– M.Hartz, K.Sakashita– code is modified to select 215 good seed-pairs for

GRNDM by K.Sakashitahttp://jnusrv01.kek.jp/Indico/getFile.py/access?

contribId=2&resId=0&materialId=slides&confId=155• OTR simulation by OTR group• Target scan simulation

– K.Matsuoka, M.Hartz• CPU saving effort• Review on gcalor (secondary interaction model)• Review on INGRID study A.Minamino

ProspectFlux Mass production• Received requests from ND280 beam group• Need to be done

– Implementation of the correct ND280 position– Optimization of proton beam area

• two flat area?– Release 10a

• In Next week at 250kA horn currentRemaining update• Striplines• Transfer matrix with new ND280 algorithm• Inclusion of NA61 results w/ NA61-T2K group• And studies.

Other geometry update

• MUMON structure has been added.• Geometry of the collimator at the entrance of DV has

been update based on the measurement.• The size of the DV entrance has been changed based

on the measurement.• Density of dump material

– concrete from 2.2 to 2.3 g/cm3 • ~1% effect on MUMON

– concrete rebars 2.3g/cm3 -> 2.377 g/cm3• <1% effect on MUMON

mag. field inside inner conductor-MUMON,1st horn only-

Primary proton profilex= 0.36, y= 0.17 (mm) Only Horn1same as April ’09 commissioning

Peak flux* x(cm) y(cm)

273 kA (min.B-field) (2.76+/-3) x 104 135+/-6 131+/-5

273 kA (realistic B-field) (2.99+/-3) x 104 129+/-5 121+/-4

273 kA (max. B-field) (3.15+/-3) x 104 125+/-4 120+/-4

0 kA (1.53+/-2) x 104 156+/-11 154+/-10

http://jnusrv01.kek.jp/Indico/getFile.py/access?contribId=1&resId=0&materialId=slides&confId=152

(*per 3.4x1011 POT, 2D fit peak)

A few % effect

Horn2&3 geometry updatepion production point (mumon)

horn1horn2

horn3 horn1

horn2

horn3 dump

target & horn1( -510 < Z < -350)

horn2(-300 < Z < -100)

horn3(350 < Z < 650)

266 0.8 0.7

09bnew

103entries / 5.0 x 107 POT

Horn2&3 geometry updateeffect of horn2&3 material

total(<10GeV) peak(/50MeV)

w/Horn2&3 material 1.21x107 1.28x106

w/o horn2&3 material 1.33x107 1.48x106

absorption ~ 10% (14%@ peak)

less effect than horn1

Horn2&3 geometry update

pions whose daughter muons goes through mumon Si-plane

horn 320kA

horn [kA] charged muons

0, 0, 0 1.99 1.68

320, 0, 0 3.68 3.15

320, 320, 0 4.84 4.15

320, 320, 320 7.94 6.92

particle flux [104 / cm2 / 3.4 x 1011POT] @MUMON Si-plane ( peak of X projection-fit )

Muon flux at muon pitEmulsion v.s. MC

A.Ariga et. al.

Comaprison Emulsion, Si, MC

31

Horn current

Shot #

Proton (CT05)

Emulsion (trk/cm2)

Si (pC)

Em/Si(trk/pC)

MC July

Em/MC July

MC Sep

Em/MC Sep

MC 09cEmu

Em/MC09c Emu

273kA 1034 3.73 x1011

2.16 +- 0.03x104

174 124 4.25 x 104

0.51 2.79x 104

0.77 2.77x 104

0.78

220kA 1170 3.77 x1011

1.61 +- 0.02x104

128 128 - - 2.26 x 104

0.71 2.15x 104

0.75

0kA 1147 3.71 x1011

1.00+- 0.02x104

77 130 1.76 x 104

0.57 1.76 x 104

0.57 1.74x 104

0.57

Proton : from beam summary (result_run24.root)Emulsion : cutoff 0.05GeV/c, <0.3radSi : using only 1 line (7 sensors) which corresponds

emulsion modules.MC : muon, position at emulsion,

momentum>0.05GeV/c, <0.3radnormalized by Proton(CT05).

Normalized at POT=3.4e11

Target scanM.Hartz

Data for y scan

Review on gcalorConsists of :

– NMTC : nucleons < 3.5GeV, π±< 2.5GeV– SCALE : Scaling Model (3GeV to 10GeV)– MICAP : neutron < 20MeV– (FLUKA) : >10GeV & other particles

NMTC & Scaling• For nucleons below 3.5GeV and π±below 2.5GeV, NMTC is

used.• Above 10GeV, FLUKA is used.• Scaling energy range (3-10GeV)

– FLUKA or (scaled)NMTC is called for each interaction with a linear probability function for smooth transition

H.Kubo

For more details, http://jnusrv01.kek.jp/Indico/getFile.py/access?contribId=2&resId=0&materialId=slides&confId=133