Precise"top/quark"mass"" - PowerPoint PPT Presentation

Precise"top/quark"mass"" at"hadron"colliders � Sayaka"Kawabata" (SeoulTech) � � Based"on � ! ""SK"and"H."Yokoya,"arXiv:1607.00990"" ! ""SK,"Y."Shimizu,"Y."Sumino"and"H."Yokoya,"" """"PLB741"(2015)"232/238 � 1"/"26 �

Outline � 1.""IntroducTon"to"m t " � eterminaTon � 2.""Diphoton"mass"spectrum " ������� 3.""Lepton"energy"distribuTon " ������� 4.""Summary � 2"/"26 �

1."IntroducTon � 3"/"26 �

MoTvaTon"to"measure"m t � ! ""One"of"the"fundamental"parameters"of"the"SM � ! ""Important"input"to"various"physics"" ★ ""EW"precision"tests"for"SM � ★ ""SM"vacuum"stability � GfiYer"Group"‘14 � BuYazzo"et"al."’13 � ★ ""Beyond"SM � 4"/"26 �

Current"status"at"hadron"colliders � Tevatron+LHC"m t "combinaTon � arXiv:1403.4427 � m t "="173.34"±"0.76"GeV � 0.4"%"precision"! � 5"/"26 �

Current"status"at"hadron"colliders � Tevatron+LHC"m t "combinaTon � arXiv:1403.4427 � m t "="173.34"±"0.76"GeV � 0.4"%"precision"! � "What"kind"of"mass? � � "m t pole ,"m t MS � “Monte/Carlo"mass” � Signal"modeling"in"MC � Experiment � jets � m t "measurement � Theory � MC �� Cannot"be"treated"" within"pert."QCD � 6"/"26 �

Current"status"at"hadron"colliders � Tevatron+LHC"m t "combinaTon � arXiv:1403.4427 � m t "="173.34"±"0.76"GeV � 0.4"%"precision"! � "What"kind"of"mass? � � "m t pole ,"m t MS � “Monte/Carlo"mass” � m t pole ,"m t MS "measurements" pole"mass"(CMS) � " "m t pole" ="173.8"±2"GeV � CMS,"JHEP"08"(2016)"029 � +5.1" " � m t MS ""="160.0""""""""GeV � −4.5 � D0,"PLB"703"(2011)"422 � The"errors"are"sTll"large. � 7"/"26 �

m t "measurement"at"future"e + e / "colliders � Threshold"scan"of"Y"producTon � b � ! "N 3 LO:"" Beneke �� Kiyo,"Marquard �� Penin,"Piclum,"" e + � t � """"""""Steinhauser,"PRL"115"(2015)192001 � W + � ! "ILC"study:"" Horiguchi,"Ishikawa,"Suehara,"Fujii,"" W − � t � """"""""""""""""Sumino,"Kiyo,"Yamamoto,"arXiv:1303.3758 � e / � √s" � "2m t � b � ! "CLIC"study:"" Seidel,"Simon,"Tesar,"Poss,"" Y"bound"state � " """""""""Eur.Phys.J.C73"(2013)2530 � Normalized"cross"secTon"for"e + e − "→"Y � Peak"posiTon"" " � "1S"resonance"mass � MS"mass � Δm t MS " � 30"MeV"in"principle � Kiyo,"Mishima,"Sumino,"JHEP11"(2015)"084 � Kiyo,"Top"WS@Valencia"2015 � 8"/"26 �

Aim"of"this"study � e + e / " � ollider " ����� � adron"collider " � " �� QCD " ���������� � top"mass " � " �������������� ������������������� " ! � Diphoton"mass"spectrum" ������� SK"and"H."Yokoya,"arXiv:1607.00990" � ! � Lepton"energy"distribuTon" ������� SK,"Y."Shimizu,"Y."Sumino"and"H."Yokoya,"" """"PLB741"(2015)"232/238 � 9"/"26 �

2."Diphoton"mass"spectrum " � " ������ SK"and"H."Yokoya,"arXiv:1607.00990" � 10"/"26 �

Diphoton"mass"spectrum � ! "H"→"γγ"" q � q � ! "New"resonance"search � + � q � q � But"large"gluon"PDF � 11"/"26 �

Diphoton"mass"spectrum � ! "H"→"γγ"" q � q � ! "New"resonance"search � + � q � q � But"large"gluon"PDF � m γγ � "2"m t � t � Bound/state"" effects � t � 12"/"26 �

gg"→"γγ"amplitude � ! "Two/loop"amplitude"for"massless/quark"loop � Bern,"De"Freitas,"Dixon,"JHEP0109"(2001)"037 � ! "One/loop"amplitude"" Dicus,"Willenbrock,"PRD37"(1988)"1801 � """for"5"massless/quark"+"top/quark"loop � Campbell,"Ellis,"Li,"Williams,"arXiv:1603.02663 � Bound/state"effects ���� "(this"work) � Near"Y"threshold" """"""""""""""""""""" ��������� t � = � + � + � Schrodinger"eq. � Green"fn." "… � = � + � + � + � + � in"NRQCD � 13"/"26 �

Diphoton"mass"spectrum"near"threshold � t � t � + � + � + � + � t � t � Light"quarks � e + e − "→"Y" ���� LHC13TeV,"gg"→"γγ � TheoreTcal"uncertainTes � " "Green"fn."scale � ! "Overall"normalizaTon � � 10"% � ! "PosiTons"of"dip"and"bump � � "sub/GeV"level � " "PDF"and"α S "scale"" � 20% � 14"/"26 �

m t "measurement"at"LHC"and"FCC � LHC"13TeV � FCC"100TeV � SimulaTon � ! "gg"→"γγ""generated"according"to"our"calculaTon � ! "qq"→"γγ" Diphox"(LO) � ! � FragmentaTon"contribuTons � Fi{ng"fn":""(gg"predicTon)"+""analyTc"smooth"fn. � 15"/"26 �

SensiTvity � EsTmate"of"staTsTcal"error � 60 LHC"√s"="13TeV"" 50 40 Δm t " � "2"GeV"for"3"ab /1 � 3"ab /1 � 30 20 10 0 170 172 174 176 m t � GeV � 80 FCC"√s"="100TeV" Δm t "="0.2"GeV"for"1"ab /1 " 60 1"ab /1 ,"10"ab /1 � 40 Δm t "="0.06"GeV"for"10"ab /1 � 20 0 172.6 172.8 173.0 173.2 173.4 m t � GeV � ! "At"FCC,"systemaTc"uncertainTes"should"dominate. � Photon"energy"scale,"isolaTon"cuts,"… � ! "Higher/order"QCD"correcTons"for"pp"→"γγ"X"would"be"important. � NLO"qq," � LO"and"NLO"qg,""NLO"gg � 16"/"26 �

3."Lepton"energy"distribuTon " � " ������ SK,"Y."Shimizu,"Y."Sumino"and"H."Yokoya,"" """"PLB741"(2015)"232/238 � 17"/"26 �

Weight"funcTon"method � SK,"Y.Shimizu,"Y.Sumino,"H.Yokoya,"PLB"710,"658"(2012) � SK,"Y.Shimizu,"Y.Sumino,"H.Yokoya,"JHEP"08,"129"(2013) � ! ""Only"lepton"energy"distribuTon"is"needed" ! "Independent"of"top/quark"velocity"distribuTon � Signal"modeling"in"MC � jets � Cannot"be"treated"" within"pert."QCD � 18"/"26 �

Weight"funcTon"method � SK,"Y.Shimizu,"Y.Sumino,"H.Yokoya,"PLB"710,"658"(2012) � SK,"Y.Shimizu,"Y.Sumino,"H.Yokoya,"JHEP"08,"129"(2013) � ! ""Only"lepton"energy"distribuTon"is"needed" ! "Independent"of"top/quark"velocity"distribuTon � Signal"modeling"in"MC � Free"from"ambiguity" � n"jets"" jets � � heoreTcally"well/defined"m t � Cannot"be"treated"" within"pert."QCD � 19"/"26 �