Charm-Tau Detector - User contributions [en]

SCT Physics Update 2021

2021-09-30T11:36:07Z

UglovTimofey: /* Участники процесса */

= Рабочие материалы =

* Overleaf
** [https://www.overleaf.com/1981928979fxfscrqwykvx Русская версия]

{| class="wikitable"
|-
! Параметр
! Значение
! Комментарий
|-
| Минимальный импульс трека
| <math>50\ MeV</math>
|
|-
| Минимальная энергия фотона
| <math>10\ MeV</math>
|
|-
| Минимальный полярный угол калориметра
| <math>10^{\circ}</math>
|
|-
| Минимальный полярный угол трека в дрейфовой камере
| <math>20^{\circ}</math>
|
|-
| Минимальный полярный угол трека в TPC
| <math>10^{\circ}</math>
|
|-
| Характерное импульское разрешение
| <math>0.5\%</math>
|
|-
| Характерное энергетическое разрешение
| <math>1.5\%</math>
|
|-
| Характерное разрешение по вершине распада
| <math>100\ \mu m</math>
|
|-
| Характерное пространственное разрешение в калориметре
| <math>6\ mm</math>
|
|-
| Магнитрое поле в детекторе
| <math>1.5\ T</math>
|
|-
| Характерное разделение пи/мю
| <math>5\sigma</math>
|
|-
| Характерное разделение K/пи
| <math>>5\sigma</math>
|
|-
|}

= Участники процесса =

* [mailto:! И.Б. Логашенко] - общая координация
* [mailto:! В.П. Дружинин] - двухфотонная физика
* [mailto:! А.Е. Бондарь] - научное руководство
* [mailto:! В.С. Воробьев] - очарованные мезоны
* [mailto:! Д.А. Епифанов] - тау лептон
* [mailto:! И.А. Рачек] - внутренняя мишень, рассеяние e+ и e- на ядрах
* [mailto:! М.Н. Ачасов] - спектроскопия легких адронов
* [mailto:! Ф.В. Игнатов] -
* [mailto:! К.Ю. Тодышев] - чармоний
* [mailto:! Т.В. Углов] - очарованные барионы

= Источники =

* SCT
** [[SCT_talks|Совещания и доклады по СЧТФ]]
* BES III
** Physics at BES-III [https://arxiv.org/abs/0809.1869 arXiv:0809.1869 hep-ex]
** Future Physics Programme of BESIII [https://arxiv.org/abs/1912.05983 arXiv:1912.05983 hep-ex]
* LHCb
** Physics case for an LHCb Upgrade II [[https://arxiv.org/abs/1808.08865 arXiv:1808.08865 hep-ex]]
* Belle II
** The Belle II Physics Book [https://arxiv.org/abs/1808.10567 arXiv:1808.10567 hep-ex]
* Обзоры
** Теория
*** I. Bigi et al, A Cicerone for the Physics of Charm [https://arxiv.org/abs/hep-ex/0309021 arXiv:hep-ex/0309021]
*** A. Pich, Tau Lepton Physics: Theory Overview [https://arxiv.org/abs/hep-ph/9612308 arXiv:hep-ph/9612308]
*** The Physics of Hadronic Tau Decays [https://arxiv.org/abs/hep-ph/0507078 arXiv:hep-ph/0507078]
*** Hadronic tau decays as New Physics probes in the LHC era [https://arxiv.org/abs/1809.01161 arXiv:1809.01161 [hep-ph]]
*** G. Buchalla et al., [https://doi.org/10.1140/epjc/s10052-008-0716-1 B, D and K decays]
** Эксперимент
*** Конференця [https://indico.nucleares.unam.mx/event/1488/timetable/#20210531.detailed Charm2020]
**** Eric BRAATEN, [https://indico.nucleares.unam.mx/event/1488/session/2/contribution/32 Exotics interpretation (Born-Oppenheimer approx)]
**** Roy BRIERE, [https://indico.nucleares.unam.mx/event/1488/session/5/contribution/37 Charm and XYZ Prospects at Belle II]
**** Frank NERLING, [https://indico.nucleares.unam.mx/event/1488/session/5/contribution/38 Charm(omium) physics at PANDA]
**** Longke LI, [https://indico.nucleares.unam.mx/event/1488/session/6/contribution/41 Recent charm results at Belle]
**** Xiaoyan SHEN, [https://indico.nucleares.unam.mx/event/1488/session/6/contribution/42 Charm Physics at BESIII/BEPCII Experiment]
**** Xiaorong ZHOU, [https://indico.nucleares.unam.mx/event/1488/session/6/contribution/43 Experimental Program for Super Tau-Charm Facility in China]
**** Mikhasenko MIKHAIL, [https://indico.nucleares.unam.mx/event/1488/session/7/contribution/48 Charm hadron spectroscopy @ LHCb]
**** Andrzej KUPSC, [https://indico.nucleares.unam.mx/event/1488/session/7/contribution/46 Precision hyperonphysics at J/Psi and Psi' factories]
**** Svetlana FAJFER, [https://indico.nucleares.unam.mx/event/1488/session/13/contribution/57 Rare semileptonic charm D decays and possible new physics in charm]
**** Emilie PASSEMAR, [https://indico.nucleares.unam.mx/event/1488/session/21/contribution/116 Tau Physics at a super-charm-tau factory]
**** Alberto LUSIANI, [https://indico.nucleares.unam.mx/event/1488/session/21/contribution/117 Tau Physics @ SCTF (experimental perspective)]
*** Конференция [https://moriond.in2p3.fr/QCD/2021/MorQCD21Prog.html Moriond 2021]
*** Конференция [https://indico.nucleares.unam.mx/event/1541/ Hadron 2021]

== Очарованные адроны ==

* PhD Thesis
** [https://eldorado.tu-dortmund.de/handle/2003/36043?mode=full Probing the standard model with rare charm decays, PhD thesis]
* Annual Review of Nuclear and Particle Science
** G. Burdman and I. Shipsey, D^0-\bar{D^0} Mixing and Rare Charm Decays, [https://doi.org/10.1146/annurev.nucl.53.041002.110348 Ann. Rev. of Nucl. and Part. 53 (2003) 431]
** G. Isidori, Y. Nir, and G. Perez, Flavor Physics Constraints for Physics Beyond the Standard Model [https://doi.org/10.1146/annurev.nucl.012809.104534 Ann. Rev. of Nucl. and Part. 60 (2010) 355]
* J. Fuentes-Martin, A. Greljo, J. M. Camalich, and J. D. Ruiz-Alvarez, [https://doi.org/10.1007/JHEP11(2020)080 Charm physics confronts high-pT lepton tails]
* FCNC
** S. Fajfer and N. Košnik, [https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-015-3801-2 Prospects of discovering new physics in rare charm decays]
** R. Bause, H. Gisbert, M. Golz, and G. Hiller, Rare charm c→uνν dineutrino null tests for e+e− machines, [https://doi.org/10.1103/PhysRevD.103.015033 Phys. Rev. D 103, 015033]
** R. Bause, H. Gisbert, M. Golz, and G. Hiller Exploiting CP asymmetries in rare charm decays [https://doi.org/10.1103/PhysRevD.101.115006 Phys. Rev. D 101, 115006]
** G. Burdman, E. Golowich, J. Hewett, and S. Pakvasa, Rare charm decays in the standard model and beyond, [https://doi.org/10.1103/PhysRevD.66.014009 Phys. Rev. D 66, 014009 – Published 29 July 2002]
* Radiative decays
** M. B. Wise, Chiral perturbation theory for hadrons containing a heavy quark, [https://doi.org/10.1103/PhysRevD.45.R2188 Phys. Rev. D 45, R2188(R) – Published 1 April 1992]
** B. Bajc, S. Fajfer, and Robert J. Oakes, Vector and pseudoscalar charm meson radiative decays, [https://doi.org/10.1103/PhysRevD.51.2230 Phys. Rev. D 51, 2230 – Published 1 March 1995]
** S. Fajfer, S. Prelovgek, P. Singer, Long distance contributions in D → Vγ decays, [https://doi.org/10.1007/s100529800914 EPJ C volume 6, pages 471–476 (1999)]
** S. Fajfer, S. Prelovsek, P. Singer, and D. Wyler, A Possible Arena for Searching New Physics - the Γ(D^0 \to ρ^0 γ)/Γ(D^0 \to ωγ) Ratio, [https://doi.org/10.1016/S0370-2693(00)00731-0 Physics Letters B Volume 487, Issues 1–2, 10 August 2000, Pages 81-86]
** S. Fajfer, P. Singer, and J. Zupan, Rare decay D0 -> γγ [https://doi.org/10.1103/PhysRevD.64.074008 Phys. Rev. D 64, 074008 – Published 4 September 2001]
** S. Fajfer, A. Prapotnik, and P. Singer, Cabibbo allowed D -> Kπγ decays, [https://doi.org/10.1103/PhysRevD.66.074002 Phys. Rev. D 66, 074002 – Published 1 October 2002]
** S. Fajfer, A. Prapotnik, and P. Singer, Charm radiative decays with neutral mesons, [https://doi.org/10.1016/S0370-2693(02)02964-7 Physics Letters B Volume 550, Issues 1–2, 12 December 2002, Pages 77-84]
** S. Boer and G. Hiller [https://doi.org/10.1007/JHEP08(2017)091 Rare radiative charm decays within the standard model and beyond]
** N. Adolph, J. Brod, and G. Hiller, Radiative three-body D-meson decays in and beyond the standard model [https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-021-08832-3 Eur. Phys. J. C 81, 45 (2021)]
** N. Adolph and G. Hiller, Probing QCD dynamics and the standard model with D_{(s)} \to P^+ P^0 γ decays, [https://doi.org/10.1007/JHEP06(2021)155 Journal of High Energy Physics volume 2021, Article number: 155 (2021)]
* A. L. Kagan and L. Silvestrini, Dispersive and Absorptive CP Violation in D^0- \overline{D^0} Mixing [https://doi.org/10.1103/PhysRevD.103.053008 Phys. Rev. D 103 (2021) 053008]
* M. Algueró, B. Capdevila, A. Crivellin, et al. Emerging patterns of New Physics with and without Lepton Flavour Universal contributions [https://link.springer.com/article/10.1140/epjc/s10052-019-7216-3 Eur. Phys. J. C 79, 714 (2019)], [https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-020-8018-3 Eur. Phys. J. C 80, 511 (2020)]

Эксперимент:

* LHCb, Searches for 25 rare and forbidden decays of D+ and D+s mesons [https://doi.org/10.1007/JHEP06(2021)044 JHEP (2021) 44]
* LHCb, Search for D+(s) -> pi+ mu+ mu- and D+(s) -> pi- mu+ mu+ decays [https://doi.org/10.1016/j.physletb.2013.06.010 Phys. Lett. B 724 (2013) 203]

<gallery widths=60px heights=60px perrow=7 caption="Slides">
File:BelleIIcharmCPV.png
File:BelleIIsigmaTime.png
</gallery>

== Тау лептон ==

* P. Blackstone, M. Fael, E. Passemar τ → μμμ at a rate of one out of 10^14 tau decays? [https://doi.org/10.1140/epjc/s10052-020-8059-7 Eur. Phys. J. C (2020) 80: 506]

Muon system simulation

2019-05-21T14:39:27Z

UglovTimofey: /* Version 0.2 */

== This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 ==

One of the most important and urgent tasks for muon system technology choice and further optimization is to create a fast and reliable simulation tool.
Optimal toolkit in this case is pure Geant4 simulation with simplified geometry and physics lists, able to produce fast results and estimate main parameters and characteristics of the detector.

== Version 0.1 ==
=== Tasks for the 0.1 version of the simulation tools ===

* Create geant4-based geometry description reflecting all main features influencing muon-related physics. The model are to be extendible to describe muon detector in detail if needed.
* Estimate basic features of the interacting muons (despite of the detector technology choice):
** Muon smearing due to the multiple scattering (depending of the muon energy, direction and/or specific production process; magnetic field ON/OFF)
** Desirable thickness of the muon system to reach maximal muon detection efficiency
** Muon/pion separation: decay point (detector layer) for the muons and pions of the same momentum, feasibility do distinguish processes based on this information
** Feasibility to distinguish pion kink: distinguish muons originated from the primary vertex and produced in the pion decays.

=== The geometry used in version 0.1 simulation ===
The following geometry is based mostly on the [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawings'''].

For simplicity, only the barrel part of the detector was simulated. The full simulation is possible, but not urgent for the first estimation.

* The following parts of the detector were simulated:
** CsI calorimeter (inner radius 1090mm, thickness 297.6 mm, which corresponds to 16 X0)
** Magnet coil (inner radius 1610mm, thickness 14.4 mm of copper, which corresponds to 1 X0)
** 9 iron absorber layers in octant geometry (see the drawings). The distance to the innermost layer is 1900mm from the beamline, the thickness of the absorber layers 30 mm,30 mm,30 mm,40 mm,40 mm,80 mm,80 mm,80 mm, respectively, which roughly corresponds to 1.7 X0, 1.7 X0, 1.7 X0, 2.3 X0, 2.3 X0, 4.5 X0, 4.5 X0, 4.5 X0.
** The 30 mm gaps between the absorber layers could be filled with organic scintillator for the energy measurement (not needed for now)
** Internal elements of the detector are estimated to give from 0.35 X0 to 0.6 X0 and are neglected in this study
** Magnetic field is NOT simulated (could be turned on if needed, though)
[[File:Det. 0000.png]] [[File:Det.gif]]
*Green: CsI calorimeter
*Violet: Cu magnet coil
*White: Fe absorber layers
*Yellow: Organic scintillator gaps

=== The source ===

Muons and pions were simulated as particles originated from the primary vertex according to the various physical distribution, taken from [https://ctd.inp.nsk.su/wiki/index.php/MC_Data_Sets '''these samples'''].
To compare detector response in case of pions and muons, pion and muon of the same sign were generated in the same event with identical momenta. During the event reconstruction all hits were categorized according to the original particle.

=== Results ===

====Muon track smearing due to the multiple scattering====

One of the base characteristics of the muon system is spacial resolution. Since all charged tracks are subjected to the multiple scattering on the material of the inner detectors and absorber, and soft tracks scatters stronger, the use of the muon system as tracking detector is questionable.
For the muon identification purposes high spacial resolution is not needed, the optimal value should be of order of the scattering spot.

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Mu 3.096 field off smearing.png]][[File:Mu 3.096 field on smearing.png]]

The same for process

<math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Tau 3.55 field off smearing.png]][[File:Tau 3.55 field on smearing.png]]

====Muon id feasibility study====

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

Magnetic field off:

[[File:Mu 3.096 field on layers.png]]

Magnetic field 1.5 Tesla on:

[[File:Mu 3.096 field off layers.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

Magnetic field off:

[[File:Tau 3.55 field on layers.png]]

Magnetic field 1.5 Tesla on:

[[File:Tau 3.55 field off layers.png]]

== Version 0.2 ==

=== Tasks for the 0.2 version of the simulation tools ===

The main task for the second round of MC simulation is to supply the parametric simulation software with the data suitable for the fast simulation.
The initial particle momenta range is [0.5,1.5] GeV/c, particle type: pi+, pi-, mu+, and mu-.

=== Geometry ===
We used the same detector geometry as in the version 0.1, except for the fact, that endcaps of the same layer structure have been added.
The uniform magnetic field of 1.5T directed along beam line were applied to the volume inside the magnet coil.

Muon system simulation

2019-05-21T14:33:08Z

UglovTimofey:

Muon system

2019-01-11T15:26:20Z

UglovTimofey: /* Useful links */

[[Category:Hardware]]
[[Category:Not_public]]

 All the information below is written for scintillator option for the muon system.

== Physics requirements ==

The design is highly physics-dependent. The list of critical questions to the physical programme of the detector:

* Major:
** Do we need KL registration with muon system?
** Which time and space resolutions for the muon track are desired?
* Minor:
** What is desired efficiency for muon reconstruction?
** Which muon ID fake rate is acceptable?
** ''TBC''

All other issues depends on the answers to the above questions.

== Simulation ==
See [https://ctd.inp.nsk.su/wiki/index.php/Muon_system_simulation '''dedicated page''']

== Conceptual design ==

== Cost estimation ==
'''The cost estimation is based on Belle II Endcap KLM system experience.'''

All prices for 1 m2 (in US dollars):
(by Vladimir Rusinov)
* polystyrene scintillating strips (7x40 mm2 x-section with diffusive reflecting coating and milled groove) $240;
* WLS fiber $250;
* SiPM - nobody knows exactly, ~12/m2 (''depends on chosen geometry''), ~$100 in 2018 prices in case of large purchase;
* labour $70 per day (~ 1 man-day per 1m2);
* other stuff: gel, polystyrene shields, connectors, scotch, silver shine paint ''etc.'' ~$10;
* packing, transportation ~$30.
Total: $700

Not included (information is requested from KEK colleagues, namely Dmitry Liventsev):

* At Belle II aluminium frames taken from the old RPC system were reused.
* Cables, connectors.
* Preamplifiers.
* Read-out electronics.
* Power supply.
* Assembly and installation costs (mostly labour).

Area estimation:
(based on [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawing'''])
''it is very rough estimation, the number of SiPMs and electronics channels highly depends on the exact geometry, while the area is practically superlayer geometry independent''

Geometry:
* Barrel part:
** 8 octants, each of
*** 8 superlayers, each of
**** 2 independent strip layers of 3820 x (2130+1300)/2 mm2 = 6.55 m2(mean value for the width) size
Total (barrel): 838.40 m2
* Endcaps:
** 2 endcaps, each of
*** 4 quadrants, each of
**** 8 superlayers, each of
***** 2 independent strip layers of (1/4 of the area of the circle with D=5500 mm MINUS 1/4 of the area of the circle with D=2120 mm) = 1/4*3.14*(5.52-2.122)/4 m2=5.05 m2
Total (endcaps): 646.40 m2

Total area: 1484.8m2

''' Total cost (excluding mechanical support, cabling, installation and electronics) $1040k=RUB 62M '''

''For a rough estimation of excluded items costs we double the total''

== Manpower ==
At LPI:
* 2 senior researchers (30-50% of working time) Timofey Uglov, Elena Solovieva
* (possible) 1-2 students from MIPT and/or MEPhI (inexperienced) ???

At BINP:
* Andrey Sukharev

== Useful links ==

'''Journal paper:'''

* [https://ctd.inp.nsk.su/wiki/images/7/70/Belle2_klm.pdf '''NIM A: A scintillator based endcap KL and muon detector for the Belle II experiment''']

'''Conference talks:'''

* [https://ctd.inp.nsk.su/wiki/images/e/e8/VRusinov_2018.pptx '''Belle II Muon system as an option for Super c-tau factory (by Vladinir Rusinov)''']

* [https://ctd.inp.nsk.su/wiki/images/a/ac/TUglov_2017.pdf '''K long and muon system for the Belle II experiment (by Timofey Uglov)''']

* [https://ctd.inp.nsk.su/wiki/images/9/91/Muon_system.pdf '''Proposal of muon system based on scintillator and WLS fiber readout: status of the simulation and prototyping (by Timofey Uglov)''']

File:Muon system.pdf

2019-01-11T15:25:39Z

UglovTimofey:

Talk:Top-10 topics for feasibility studies

2018-12-10T14:03:07Z

UglovTimofey:

I would add measurement of the ee->cc x-section (both exclusive and inclusive) at the threshold and in mid-energy region

// Timofey

This task could be assigned to our (LPI) group

//Timfoey

Talk:Top-10 topics for feasibility studies

2018-12-10T14:01:55Z

UglovTimofey: Created page with "I would add measurement of the ee->cc x-section (both exclusive and inclusive) at the threshold and in mid-energy region // Timofey"

I would add measurement of the ee->cc x-section (both exclusive and inclusive) at the threshold and in mid-energy region

// Timofey

Muon system simulation

2018-11-14T16:12:58Z

UglovTimofey: /* Muon id feasibility study */

== This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 ==

One of the most important and urgent tasks for muon system technology choice and further optimization is to create a fast and reliable simulation tool.
Optimal toolkit in this case is pure Geant4 simulation with simplified geometry and physics lists, able to produce fast results and estimate main parameters and characteristics of the detector.

=== Tasks for the 0.1 version of the simulation tools ===

* Create geant4-based geometry description reflecting all main features influencing muon-related physics. The model are to be extendible to describe muon detector in detail if needed.
* Estimate basic features of the interacting muons (despite of the detector technology choice):
** Muon smearing due to the multiple scattering (depending of the muon energy, direction and/or specific production process; magnetic field ON/OFF)
** Desirable thickness of the muon system to reach maximal muon detection efficiency
** Muon/pion separation: decay point (detector layer) for the muons and pions of the same momentum, feasibility do distinguish processes based on this information
** Feasibility to distinguish pion kink: distinguish muons originated from the primary vertex and produced in the pion decays.

=== The geometry used in version 0.1 simulation ===
The following geometry is based mostly on the [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawings'''].

For simplicity, only the barrel part of the detector was simulated. The full simulation is possible, but not urgent for the first estimation.

* The following parts of the detector were simulated:
** CsI calorimeter (inner radius 1090mm, thickness 297.6 mm, which corresponds to 16 X0)
** Magnet coil (inner radius 1610mm, thickness 14.4 mm of copper, which corresponds to 1 X0)
** 9 iron absorber layers in octant geometry (see the drawings). The distance to the innermost layer is 1900mm from the beamline, the thickness of the absorber layers 30 mm,30 mm,30 mm,40 mm,40 mm,80 mm,80 mm,80 mm, respectively, which roughly corresponds to 1.7 X0, 1.7 X0, 1.7 X0, 2.3 X0, 2.3 X0, 4.5 X0, 4.5 X0, 4.5 X0.
** The 30 mm gaps between the absorber layers could be filled with organic scintillator for the energy measurement (not needed for now)
** Internal elements of the detector are estimated to give from 0.35 X0 to 0.6 X0 and are neglected in this study
** Magnetic field is NOT simulated (could be turned on if needed, though)
[[File:Det. 0000.png]] [[File:Det.gif]]
*Green: CsI calorimeter
*Violet: Cu magnet coil
*White: Fe absorber layers
*Yellow: Organic scintillator gaps

=== The source ===

Muons and pions were simulated as particles originated from the primary vertex according to the various physical distribution, taken from [https://ctd.inp.nsk.su/wiki/index.php/MC_Data_Sets '''these samples'''].
To compare detector response in case of pions and muons, pion and muon of the same sign were generated in the same event with identical momenta. During the event reconstruction all hits were categorized according to the original particle.

== Results ==

====Muon track smearing due to the multiple scattering====

One of the base characteristics of the muon system is spacial resolution. Since all charged tracks are subjected to the multiple scattering on the material of the inner detectors and absorber, and soft tracks scatters stronger, the use of the muon system as tracking detector is questionable.
For the muon identification purposes high spacial resolution is not needed, the optimal value should be of order of the scattering spot.

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Mu 3.096 field off smearing.png]][[File:Mu 3.096 field on smearing.png]]

The same for process

<math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Tau 3.55 field off smearing.png]][[File:Tau 3.55 field on smearing.png]]

====Muon id feasibility study====

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

Magnetic field off:

[[File:Mu 3.096 field on layers.png]]

Magnetic field 1.5 Tesla on:

[[File:Mu 3.096 field off layers.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

Magnetic field off:

[[File:Tau 3.55 field on layers.png]]

Magnetic field 1.5 Tesla on:

[[File:Tau 3.55 field off layers.png]]

Muon system simulation

2018-11-14T16:08:44Z

UglovTimofey: /* Muon id feasibility study */

== This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 ==

One of the most important and urgent tasks for muon system technology choice and further optimization is to create a fast and reliable simulation tool.
Optimal toolkit in this case is pure Geant4 simulation with simplified geometry and physics lists, able to produce fast results and estimate main parameters and characteristics of the detector.

=== Tasks for the 0.1 version of the simulation tools ===

* Create geant4-based geometry description reflecting all main features influencing muon-related physics. The model are to be extendible to describe muon detector in detail if needed.
* Estimate basic features of the interacting muons (despite of the detector technology choice):
** Muon smearing due to the multiple scattering (depending of the muon energy, direction and/or specific production process; magnetic field ON/OFF)
** Desirable thickness of the muon system to reach maximal muon detection efficiency
** Muon/pion separation: decay point (detector layer) for the muons and pions of the same momentum, feasibility do distinguish processes based on this information
** Feasibility to distinguish pion kink: distinguish muons originated from the primary vertex and produced in the pion decays.

=== The geometry used in version 0.1 simulation ===
The following geometry is based mostly on the [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawings'''].

For simplicity, only the barrel part of the detector was simulated. The full simulation is possible, but not urgent for the first estimation.

* The following parts of the detector were simulated:
** CsI calorimeter (inner radius 1090mm, thickness 297.6 mm, which corresponds to 16 X0)
** Magnet coil (inner radius 1610mm, thickness 14.4 mm of copper, which corresponds to 1 X0)
** 9 iron absorber layers in octant geometry (see the drawings). The distance to the innermost layer is 1900mm from the beamline, the thickness of the absorber layers 30 mm,30 mm,30 mm,40 mm,40 mm,80 mm,80 mm,80 mm, respectively, which roughly corresponds to 1.7 X0, 1.7 X0, 1.7 X0, 2.3 X0, 2.3 X0, 4.5 X0, 4.5 X0, 4.5 X0.
** The 30 mm gaps between the absorber layers could be filled with organic scintillator for the energy measurement (not needed for now)
** Internal elements of the detector are estimated to give from 0.35 X0 to 0.6 X0 and are neglected in this study
** Magnetic field is NOT simulated (could be turned on if needed, though)
[[File:Det. 0000.png]] [[File:Det.gif]]
*Green: CsI calorimeter
*Violet: Cu magnet coil
*White: Fe absorber layers
*Yellow: Organic scintillator gaps

=== The source ===

Muons and pions were simulated as particles originated from the primary vertex according to the various physical distribution, taken from [https://ctd.inp.nsk.su/wiki/index.php/MC_Data_Sets '''these samples'''].
To compare detector response in case of pions and muons, pion and muon of the same sign were generated in the same event with identical momenta. During the event reconstruction all hits were categorized according to the original particle.

== Results ==

====Muon track smearing due to the multiple scattering====

One of the base characteristics of the muon system is spacial resolution. Since all charged tracks are subjected to the multiple scattering on the material of the inner detectors and absorber, and soft tracks scatters stronger, the use of the muon system as tracking detector is questionable.
For the muon identification purposes high spacial resolution is not needed, the optimal value should be of order of the scattering spot.

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Mu 3.096 field off smearing.png]][[File:Mu 3.096 field on smearing.png]]

The same for process

<math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Tau 3.55 field off smearing.png]][[File:Tau 3.55 field on smearing.png]]

====Muon id feasibility study====

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

Magnetic off:

[[File:Mu 3.096 field on layers.png]]

Magnetic 1.5 Tesla on:

[[File:Mu 3.096 field off layers.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

Magnetic off:

[[File:Tau 3.55 field on layers.png]]

Magnetic 1.5 Tesla on:

[[File:Tau 3.55 field off layers.png]]

Muon system simulation

2018-11-14T16:04:34Z

UglovTimofey: /* Muon track smearing due to the multiple scattering */

== This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 ==

One of the most important and urgent tasks for muon system technology choice and further optimization is to create a fast and reliable simulation tool.
Optimal toolkit in this case is pure Geant4 simulation with simplified geometry and physics lists, able to produce fast results and estimate main parameters and characteristics of the detector.

=== Tasks for the 0.1 version of the simulation tools ===

* Create geant4-based geometry description reflecting all main features influencing muon-related physics. The model are to be extendible to describe muon detector in detail if needed.
* Estimate basic features of the interacting muons (despite of the detector technology choice):
** Muon smearing due to the multiple scattering (depending of the muon energy, direction and/or specific production process; magnetic field ON/OFF)
** Desirable thickness of the muon system to reach maximal muon detection efficiency
** Muon/pion separation: decay point (detector layer) for the muons and pions of the same momentum, feasibility do distinguish processes based on this information
** Feasibility to distinguish pion kink: distinguish muons originated from the primary vertex and produced in the pion decays.

=== The geometry used in version 0.1 simulation ===
The following geometry is based mostly on the [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawings'''].

For simplicity, only the barrel part of the detector was simulated. The full simulation is possible, but not urgent for the first estimation.

* The following parts of the detector were simulated:
** CsI calorimeter (inner radius 1090mm, thickness 297.6 mm, which corresponds to 16 X0)
** Magnet coil (inner radius 1610mm, thickness 14.4 mm of copper, which corresponds to 1 X0)
** 9 iron absorber layers in octant geometry (see the drawings). The distance to the innermost layer is 1900mm from the beamline, the thickness of the absorber layers 30 mm,30 mm,30 mm,40 mm,40 mm,80 mm,80 mm,80 mm, respectively, which roughly corresponds to 1.7 X0, 1.7 X0, 1.7 X0, 2.3 X0, 2.3 X0, 4.5 X0, 4.5 X0, 4.5 X0.
** The 30 mm gaps between the absorber layers could be filled with organic scintillator for the energy measurement (not needed for now)
** Internal elements of the detector are estimated to give from 0.35 X0 to 0.6 X0 and are neglected in this study
** Magnetic field is NOT simulated (could be turned on if needed, though)
[[File:Det. 0000.png]] [[File:Det.gif]]
*Green: CsI calorimeter
*Violet: Cu magnet coil
*White: Fe absorber layers
*Yellow: Organic scintillator gaps

=== The source ===

Muons and pions were simulated as particles originated from the primary vertex according to the various physical distribution, taken from [https://ctd.inp.nsk.su/wiki/index.php/MC_Data_Sets '''these samples'''].
To compare detector response in case of pions and muons, pion and muon of the same sign were generated in the same event with identical momenta. During the event reconstruction all hits were categorized according to the original particle.

== Results ==

====Muon track smearing due to the multiple scattering====

One of the base characteristics of the muon system is spacial resolution. Since all charged tracks are subjected to the multiple scattering on the material of the inner detectors and absorber, and soft tracks scatters stronger, the use of the muon system as tracking detector is questionable.
For the muon identification purposes high spacial resolution is not needed, the optimal value should be of order of the scattering spot.

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process

<math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Mu 3.096 field off smearing.png]][[File:Mu 3.096 field on smearing.png]]

The same for process

<math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.
left: Magnetic field off ; right: magnetic field of 1.5 Tesla on

[[File:Tau 3.55 field off smearing.png]][[File:Tau 3.55 field on smearing.png]]

====Muon id feasibility study====

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process <math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

[[File:Muon jpsi field off layers.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

[[File:Tau 3.55 field off layers.png]]

File:Tau 3.55 field on smearing.png

2018-11-14T15:59:48Z

UglovTimofey:

File:Tau 3.55 field on layers.png

2018-11-14T15:59:29Z

UglovTimofey:

File:Tau 3.55 field off smearing.png

2018-11-14T15:59:01Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Tau 3.55 field off smearing.png"

File:Tau 3.55 field off layers.png

2018-11-14T15:58:38Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Tau 3.55 field off layers.png"

File:Mu 3.096 field on smearing.png

2018-11-14T15:58:20Z

UglovTimofey:

File:Mu 3.096 field on layers.png

2018-11-14T15:57:59Z

UglovTimofey:

File:Mu 3.096 field off smearing.png

2018-11-14T15:57:37Z

UglovTimofey:

File:Mu 3.096 field off layers.png

2018-11-14T15:57:13Z

UglovTimofey: modified

modified

File:Muon jpsi field off layers.png

2018-11-14T15:49:53Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Muon jpsi field off layers.png"

File:Muon jpsi field off smearing.png

2018-11-14T15:49:29Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Muon jpsi field off smearing.png"

File:Muon jpsi uniform field on layers.png

2018-11-14T15:48:58Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Muon jpsi uniform field on layers.png"

File:Muon jpsi uniform field on smearing.png

2018-11-14T15:48:32Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Muon jpsi uniform field on smearing.png"

File:Tau 3.55 field off layers.png

2018-11-14T15:48:06Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Tau 3.55 field off layers.png"

File:Tau 3.55 field off smearing.png

2018-11-14T15:47:44Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Tau 3.55 field off smearing.png"

File:Tau 3.55 uniform field on layers.png

2018-11-14T15:46:47Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Tau 3.55 uniform field on layers.png"

File:Tau 3.55 uniform field on smearing.png

2018-11-14T15:46:21Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Tau 3.55 uniform field on smearing.png"

SCT talks

2018-11-13T05:55:53Z

UglovTimofey: /* Seminars */

= Dedicated workshops =
== 2018, Dec 4-7, LAL Orsay ==
* [http://workshop-tau-charm-factory.lal.in2p3.fr/ Joint meeting of Novosibirsk and Hefei projects].

== 2018, May 26-27, BINP ==
* CREMLIN WP7, [https://indico.inp.nsk.su/event/13/other-view?view=standard the second meeting on Novosibirsk project of Super c-tau factory]

== 2017, December 18-19, BINP ==
* [[1st_workshop_on_physics_at_SCTF | Takls and slides]]

= Conference talks =
{| class="wikitable"
|-
! Date || Event || Location || Title || Speaker || Agenda || Slides
|-
| 2017.10.12 || 10th GSO Meeting || JINR || Accelerator complex with colliding electron-positron beams || Pavel Logachev || [https://gso.msk.ru/presentations/ list of talks] || [https://gso.msk.ru/Downloads/Presentations/Accelerator%20complex%20with%20colliding%20electron-positron%20beams.ppt slides]
|-
| 2018.05.21 || CHARM18 || BINP || A project of Super-charm-tau Factory in Novosibirsk || Eugene Levichev || [https://indico.inp.nsk.su/event/10/timetable indico] || [https://indico.inp.nsk.su/event/10/session/1/contribution/65/material/slides/0.pdf slides]
|-
| 2018.03.21 || 2nd workshop on HIEPA || Beijing || Injection facility for Novosibirsk Super Charm Tau Factory || Dmitry Berkaev || [http://cicpi.ustc.edu.cn/indico/conferenceOtherViews.py?view=standard&confId=1009#20180318 indico] || [http://cicpi.ustc.edu.cn/indico/getFile.py/access?contribId=33&sessionId=18&resId=0&materialId=slides&confId=1009 slides]
|-
| 2018.03.21 || 2nd workshop on HIEPA || Beijing || Particle Identification systems based on aerogel at BINP || Alexander Barnyakov || [http://cicpi.ustc.edu.cn/indico/conferenceOtherViews.py?view=standard&confId=1009#20180318 indico] || [http://cicpi.ustc.edu.cn/indico/getFile.py/access?contribId=40&sessionId=22&resId=0&materialId=slides&confId=1009 slides]
|-
| 2018.07.06 || ICHEP 2018 || Seoul || Super Charm-Tau Factory in Novosibirsk || Eugene Levichev || [https://indico.cern.ch/event/686555/sessions/276022/#20180706 indico] || [https://indico.cern.ch/event/686555/contributions/2962543/ contribution page]
|}

= Seminars =
{| class="wikitable"
|-
! Date || Organization || Location || Title || Speaker || Slides
|-
| 2018.03.26 || Milano University Bicocсa || Italy || The BINP Super Charm-Tau Factory project || Alexander Barnyakov || [[:Media:Ctau2018march_Milano_pr.pdf|slides]]
|-
| 2018.06.26 || INFN Pisa|| Italy || The e+e- experiments in the BINP and the super c-tau factory project || Fedor Ignatov || [[:Media:BINPaccelCTau_ctau_2018Pisa_2parts.pdf|slides]]
|-
| 2018.09.27 || PNPI || St. Petersburg || Проект "Супер С-Тау фабрики" || Alexander Barnyakov, Vitaly Vorobyev || [[:Media:Super-c-tau-PNPI-Sept2018_noanim.pdf|part1]] [[:Media:ctau_det2018sept.pdf|part2]]
|-
| 2018.11.02 || BINP || Novosibirsk || SCTF: accelerator project || Pavel Piminov || [[:Media:Piminov_-_Super-ct-Factory_for_scd-software.pdf|slides]]
|-
| 2018.11.09 || BINP || Novosibirsk || Drift chamber design proposal SCTF || Korneliy Todyshev || [[:Media:DCvariant.pdf|slides]]
|-
| 2018.11.13 || BINP || Novosibirsk || Muon system for the Super c-tau factory || Timofey Uglov || [[:Media:Uglov_2018_11_13_Talk.pdf|slides]]
|}

= Misc =
{| class="wikitable"
|-
! Date || Event || Location || Title || Speaker || Agenda || Slides
|-
| 2018.04.09 || VII ММК "ФЭЧ и космология 2018" || LPI, Moscow || Физика на Супер-c-tau фабрике || Vitaly Vorobyev || [http://belle.lebedev.ru/conf_lpi_2018/?page_id=257 agenda] || [http://belle.lebedev.ru/conf_lpi_2018/wp-content/uploads/participants-database/super-c-tau-lpi-2018.pptx slides]
|-
| 2018.03.16 || Научная сессия ИЯФ || BINP || Физическая программа Супер С-Тау фабрики || Vitaly Vorobyev || [http://www.inp.nsk.su/sobytia/nauchnye-sessii/2018 agenda] || [http://www.inp.nsk.su/images/pdf/sessii/08%20%D0%92%D0%BE%D1%80%D0%BE%D0%B1%D1%8C%D0%B5%D0%B2.%20%D0%A4%D0%B8%D0%B7%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B0%D1%8F%20%D0%BF%D1%80%D0%BE%D0%B3%D1%80%D0%B0%D0%BC%D0%BC%D0%B0%20%D0%A1%D1%83%D0%BF%D0%B5%D1%80%20%D0%A1-%D0%A2%D0%B0%D1%83%20%D1%84%D0%B0%D0%B1%D1%80%D0%B8%D0%BA%D0%B8.pdf slides]
|-
| 2018.03.16 || Научная сессия ИЯФ || BINP || Статус проекта Супер С-Тау фабрики || Eugene Levichev || [http://www.inp.nsk.su/sobytia/nauchnye-sessii/2018 agenda] || [http://www.inp.nsk.su/images/pdf/sessii/09%20%D0%95.%20%D0%9B%D0%B5%D0%B2%D0%B8%D1%87%D0%B5%D0%B2.%20%D0%A1%D1%82%D0%B0%D1%82%D1%83%D1%81%20%D0%BF%D1%80%D0%BE%D0%B5%D0%BA%D1%82%D0%B0%20%D0%A1%D1%83%D0%BF%D0%B5%D1%80%20%D0%A1-%D0%A2%D0%B0%D1%83%20%D1%84%D0%B0%D0%B1%D1%80%D0%B8%D0%BA%D0%B8.pdf slides]
|-
| 2017.01.27 || Научная сессия ИЯФ || BINP || Перспективные детекторные технологии для будущих экспериментов || Barnyakov Alexander || [http://www.inp.nsk.su/sobytia/nauchnye-sessii/2017 agenda] || [http://www.inp.nsk.su/news/rss/2017_196_07Barnyakov.pdf slides]
|-
| 2014.02.07 || Научная сессия ИЯФ || BINP || Проект Супер Чарм-Тау фабрики || Eugene Levichev || [http://www.inp.nsk.su/sobytia/nauchnye-sessii/2014 agenda] || [http://www.inp.nsk.su/news/rss/2014_136_09Skniskiy.pdf slides]
|}

--[[User:V.S.Vorobev|V.S.Vorobev]] ([[User talk:V.S.Vorobev|talk]]) 15:35, 30 May 2018 (+07)
[[Category:Software]]

Muon system simulation

2018-11-13T01:49:38Z

UglovTimofey:

== This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 ==

One of the most important and urgent tasks for muon system technology choice and further optimization is to create a fast and reliable simulation tool.
Optimal toolkit in this case is pure Geant4 simulation with simplified geometry and physics lists, able to produce fast results and estimate main parameters and characteristics of the detector.

=== Tasks for the 0.1 version of the simulation tools ===

* Create geant4-based geometry description reflecting all main features influencing muon-related physics. The model are to be extendible to describe muon detector in detail if needed.
* Estimate basic features of the interacting muons (despite of the detector technology choice):
** Muon smearing due to the multiple scattering (depending of the muon energy, direction and/or specific production process; magnetic field ON/OFF)
** Desirable thickness of the muon system to reach maximal muon detection efficiency
** Muon/pion separation: decay point (detector layer) for the muons and pions of the same momentum, feasibility do distinguish processes based on this information
** Feasibility to distinguish pion kink: distinguish muons originated from the primary vertex and produced in the pion decays.

=== The geometry used in version 0.1 simulation ===
The following geometry is based mostly on the [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawings'''].

For simplicity, only the barrel part of the detector was simulated. The full simulation is possible, but not urgent for the first estimation.

* The following parts of the detector were simulated:
** CsI calorimeter (inner radius 1090mm, thickness 297.6 mm, which corresponds to 16 X0)
** Magnet coil (inner radius 1610mm, thickness 14.4 mm of copper, which corresponds to 1 X0)
** 9 iron absorber layers in octant geometry (see the drawings). The distance to the innermost layer is 1900mm from the beamline, the thickness of the absorber layers 30 mm,30 mm,30 mm,40 mm,40 mm,80 mm,80 mm,80 mm, respectively, which roughly corresponds to 1.7 X0, 1.7 X0, 1.7 X0, 2.3 X0, 2.3 X0, 4.5 X0, 4.5 X0, 4.5 X0.
** The 30 mm gaps between the absorber layers could be filled with organic scintillator for the energy measurement (not needed for now)
** Internal elements of the detector are estimated to give from 0.35 X0 to 0.6 X0 and are neglected in this study
** Magnetic field is NOT simulated (could be turned on if needed, though)
[[File:Det. 0000.png]] [[File:Det.gif]]
*Green: CsI calorimeter
*Violet: Cu magnet coil
*White: Fe absorber layers
*Yellow: Organic scintillator gaps

=== The source ===

Muons and pions were simulated as particles originated from the primary vertex according to the various physical distribution, taken from [https://ctd.inp.nsk.su/wiki/index.php/MC_Data_Sets '''these samples'''].
To compare detector response in case of pions and muons, pion and muon of the same sign were generated in the same event with identical momenta. During the event reconstruction all hits were categorized according to the original particle.

== Results ==

====Muon track smearing due to the multiple scattering====

One of the base characteristics of the muon system is spacial resolution. Since all charged tracks are subjected to the multiple scattering on the material of the inner detectors and absorber, and soft tracks scatters stronger, the use of the muon system as tracking detector is questionable.
For the muon identification purposes high spacial resolution is not needed, the optimal value should be of order of the scattering spot.

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process <math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

[[File:Muon jpsi field off smearing.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

[[File:Tau 3.55 field off smearing.png]]

====Muon id feasibility study====

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process <math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

[[File:Muon jpsi field off layers.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

[[File:Tau 3.55 field off layers.png]]

Muon system simulation

2018-11-13T01:46:55Z

UglovTimofey: /* Muon track smearing due to the multiple scattering */

== This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 ==

One of the most important and urgent tasks for muon system technology choice and further optimization is to create a fast and reliable simulation tool.
Optimal toolkit in this case is pure Geant4 simulation with simplified geometry and physics lists, able to produce fast results and estimate main parameters and characteristics of the detector.

=== Tasks for the 0.1 version of the simulation tools ===

* Create geant4-based geometry description reflecting all main features influencing muon-related physics. The model are to be extendible to describe muon detector in detail if needed.
* Estimate basic features of the interacting muons (despite of the detector technology choice):
** Muon smearing due to the multiple scattering (depending of the muon energy, direction and/or specific production process; magnetic field ON/OFF)
** Desirable thickness of the muon system to reach maximal muon detection efficiency
** Muon/pion separation: decay point (detector layer) for the muons and pions of the same momentum, feasibility do distinguish processes based on this information
** Feasibility to distinguish pion kink: distinguish muons originated from the primary vertex and produced in the pion decays.

=== The geometry used in version 0.1 simulation ===
The following geometry is based mostly on the [https://ctd.inp.nsk.su/docs/CTauFactory/Drawings/Detector/Detector_Model.pdf '''this drawings'''].

For simplicity, only the barrel part of the detector was simulated. The full simulation is possible, but not urgent for the first estimation.

* The following parts of the detector were simulated:
** CsI calorimeter (inner radius 1090mm, thickness 297.6 mm, which corresponds to 16 X0)
** Magnet coil (inner radius 1610mm, thickness 14.4 mm of copper, which corresponds to 1 X0)
** 9 iron absorber layers in octant geometry (see the drawings). The distance to the innermost layer is 1900mm from the beamline, the thickness of the absorber layers 30 mm,30 mm,30 mm,40 mm,40 mm,80 mm,80 mm,80 mm, respectively, which roughly corresponds to 1.7 X0, 1.7 X0, 1.7 X0, 2.3 X0, 2.3 X0, 4.5 X0, 4.5 X0, 4.5 X0.
** The 30 mm gaps between the absorber layers could be filled with organic scintillator for the energy measurement (not needed for now)
** Internal elements of the detector are estimated to give from 0.35 X0 to 0.6 X0 and are neglected in this study
** Magnetic field is NOT simulated (could be turned on if needed, though)
[[File:Det. 0000.png]] [[File:Det.gif]]
*Green: CsI calorimeter
*Violet: Cu magnet coil
*White: Fe absorber layers
*Yellow: Organic scintillator gaps

=== The source ===

Muons and pions were simulated as particles originated from the primary vertex according to the various physical distribution, taken from [https://ctd.inp.nsk.su/wiki/index.php/MC_Data_Sets '''these samples'''].
To compare detector response in case of pions and muons, pion and muon of the same sign were generated in the same event with identical momenta. During the event reconstruction all hits were categorized according to the original particle.

== Results ==

====Muon track smearing due to the multiple scattering====

One of the base characteristics of the muon system is spacial resolution. Since all charged tracks are subjected to the multiple scattering on the material of the inner detectors and absorber, and soft tracks scatters stronger, the use of the muon system as tracking detector is questionable.
For the muon identification purposes high spacial resolution is not needed, the optimal value should be of order of the scattering spot.

With the setup, described above, Monte Carlo simulation of the muon events for the 1st and 7th gap of absorber is shown. The smearing along Z axis is due to the multiple scattering on the calorimeter, magnet and absorber. Upper pictures corresponds to the energy-weighted position of the the hit, lower to the true position of muon/pion, respectively. The simulated physical process <math>e^+e^- \to J/\psi \to \mu^+ \mu^-</math> at E=3.096 GeV.

[[File:Muon jpsi field off smearing.png]]

The same for process <math>e^+e^- \to \tau^+ \tau^-</math> at E=3.3.55GeV.

[[File:Tau 3.55 field off smearing.png]]

File:Tau 3.55 uniform field on smearing.png

2018-11-13T01:44:01Z

UglovTimofey:

File:Tau 3.55 uniform field on layers.png

2018-11-13T01:43:47Z

UglovTimofey:

File:Tau 3.55 field off smearing.png

2018-11-13T01:43:36Z

UglovTimofey:

File:Tau 3.55 field off layers.png

2018-11-13T01:43:23Z

UglovTimofey:

File:Muon jpsi uniform field on smearing.png

2018-11-13T01:33:37Z

UglovTimofey:

File:Muon jpsi uniform field on layers.png

2018-11-13T01:33:25Z

UglovTimofey:

File:Muon jpsi field off smearing.png

2018-11-13T01:33:08Z

UglovTimofey:

File:Muon jpsi field off layers.png

2018-11-13T01:32:49Z

UglovTimofey:

Muon system simulation

2018-11-08T16:02:40Z

UglovTimofey: /* Results */

File:Smearing no field mu from jpsi.png

2018-11-08T15:42:19Z

UglovTimofey:

Muon system simulation

2018-11-08T15:40:28Z

UglovTimofey: /* The source */

Muon system simulation

2018-10-30T13:52:03Z

UglovTimofey: /* This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 */

File:Det. 0000.png

2018-10-30T13:50:39Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Det. 0000.png": Reverted to version as of 17:20, 29 October 2018

Detector used in for the Muon system simulation version 0.1

Muon system simulation

2018-10-30T13:49:07Z

UglovTimofey: /* The geometry used in version 0.1 simulation */

Muon system simulation

2018-10-30T13:47:17Z

UglovTimofey: /* The geometry used in version 0.1 simulation */

File:Det.gif

2018-10-30T13:46:52Z

UglovTimofey: detector simulation ver 0.1

detector simulation ver 0.1

File:Det. 0000.png

2018-10-30T13:43:50Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Det. 0000.png"

Detector used in for the Muon system simulation version 0.1

Muon system simulation

2018-10-29T17:21:55Z

UglovTimofey: /* The geometry used in version 0.1 simulation */

File:Det. 0000.png

2018-10-29T17:20:52Z

UglovTimofey: UglovTimofey uploaded a new version of "File:Det. 0000.png"

Detector used in for the Muon system simulation version 0.1

File:Det. 0000.png

2018-10-29T17:13:33Z

UglovTimofey: Detector used in for the Muon system simulation version 0.1

Detector used in for the Muon system simulation version 0.1

Muon system simulation

2018-10-29T17:08:44Z

UglovTimofey:

Muon system simulation

2018-10-29T17:03:47Z

UglovTimofey: /* This page is dedicated to the sketch standalone simulation of the SCT detector based on pure Geant4 */