Search for Lepton-Flavor Violation in Z-Boson Decays with τ Leptons with the ATLAS Detector

Sea ch o Lep on-Fla o Viola ion in Z-Boson Decays wi h τLep ons
wi h he ATLAS De ec o
G. Aad e al.*
(ATLAS Collabo a ion)
(Recei ed 1 June 2021; accep ed 5 Oc obe 2021; published 28 Decembe 2021)
A sea ch o lep on- la o - iola ing Z→eτand Z→μτ decays wi h pp collision da a eco ded by he
ATLAS de ec o a he LHC is p esen ed. This analysis uses 139 b−1o Run 2 pp collisions a ffiffiffi
s
p¼
13 TeV and is combined wi h he esul s o a simila ATLAS sea ch in he inal s a e in which he τlep on
decays had onically, using he same da a se as well as Run 1 da a. The addi ion o lep onically decaying τ
lep ons signi ican ly imp o es he sensi i i y each o Z→lτdecays. The Z→lτb anching ac ions a e
cons ained in his analysis o BðZ→eτÞ<7.0×10−6and BðZ→μτÞ<7.2×10−6a 95% con idence
le el. The combina ion wi h he p e iously published analyses se s he s onges cons ain s o da e:
BðZ→eτÞ<5.0×10−6and BðZ→μτÞ<6.5×10−6a 95% con idence le el.
DOI: 10.1103/PhysRe Le .127.271801
Th ee lep on amilies ( la o s) exis in he s anda d
model (SM) o pa icle physics [1–4], and he numbe o
lep ons o each amily is conse ed in hei in e ac ions.
Ne e heless, his conse a ion is no pos ula ed by any
undamen al p inciple o he heo y, and neu ino oscil-
la ions [5,6] indica e ha p ocesses iola ing his conse -
a ion do occu in na u e. Acco ding o cu en knowledge,
lep on- la o - iola ing (LFV) p ocesses in cha ged-lep on
in e ac ions can occu ia neu ino mixing bu a e oo a e
o be de ec ed by cu en expe imen s [7]. An obse a ion
o hese would be an unambiguous sign o physics beyond
he SM. LFV p ocesses occu , o example, in models
p edic ing he exis ence o hea y neu inos [8], which may
also explain he obse ed iny masses and la ge mixing o
he SM neu inos. In such models, up o one in 105Z
bosons would unde go an LFV decay in ol ing τlep ons.
In an ea lie analysis, he ATLAS expe imen a he LHC
se he s onges cons ain s on he b anching ac ions (B)
o he LFV decays o he Zboson in ol ing a τlep on by
sea ching o such decays in which he τlep on decays
had onically [9]. This esul was achie ed by analyzing
p o on-p o on (pp) collision da a co esponding o an
in eg a ed luminosi y o 139 b−1a a cen e -o -mass
ene gy ffiffiffi
s
p¼13 TeV and 20.3 b−1a ffiffiffi
s
p¼8TeV. In
ha sea ch, ATLAS measu ed he b anching ac ions o be
BðZ→eτÞ<8.1×10−6and BðZ→μτÞ<9.5×10−6a
95% con idence le el (C.L.), supe seding o me limi s se
by he LEP expe imen s o BðZ→eτÞ<9.8×10−6[10]
and BðZ→μτÞ<1.2×10−5[11] a 95% C.L.
This Le e p esen s a complemen a y sea ch o Z→lτ
decays (l¼ligh cha ged lep on, i.e., eo μ) in which he τ
lep ons decay in o elec ons o muons (lτl0channel) using
139 b−1o pp collision da a a ffiffiffi
s
p¼13 TeV collec ed by
he ATLAS expe imen [12–14]. The sea ch is pe o med
he e o he i s ime a he LHC and is combined wi h he
simila ATLAS sea ch using had onic τ-lep on decays
(lτhad channel) [9]. The wo sea ches ollow simila
analysis s a egies. Neu al ne wo k classi ie s a e used
o op imal disc imina ion o signal om backg ounds
and hei dis ibu ions a e employed in a binned maxi-
mum-likelihood i o achie e be e sensi i i y.
ATLAS is a mul ipu pose pa icle de ec o wi h a
o wa d-backwa d symme ic cylind ical geome y and a
nea 4πco e age in solid angle [12,15,16]. I consis s o an
inne acking de ec o su ounded by a supe conduc ing
solenoid, elec omagne ic and had onic calo ime e s, and a
muon spec ome e based on supe conduc ing ai -co e
o oidal magne s. This sea ch analyzes pp collision e en s
eco ded by he ATLAS expe imen using single-elec on
o single-muon igge s [17–19]. P omp elec ons and
muons om he Z-boson decays and hose om he
τ-lep on decays a e econs uc ed and selec ed in he same
way. Candida es o elec ons [20], muons [21], je s
[22–24], and isible decay p oduc s o had onic τ-lep on
decays (τhad- is)[25,26] a e econs uc ed om ene gy
deposi s in he calo ime e s and cha ged-pa icle acks
measu ed in he inne de ec o and he muon spec ome e .
These candida es a e selec ed wi h se s o equi emen s
simila o hose used in Re . [9]. Elec on candida es a e
equi ed o pass he medium likelihood-based iden i ica-
ion equi emen [20] and ha e a ans e se momen um
*Full au ho lis gi en a he end o he a icle.
Published by he Ame ican Physical Socie y unde he e ms o
he C ea i e Commons A ibu ion 4.0 In e na ional license.
Fu he dis ibu ion o his wo k mus main ain a ibu ion o
he au ho (s) and he published a icle’s i le, jou nal ci a ion,
and DOI. Funded by SCOAP3.
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
0031-9007=21=127(27)=271801(20) 271801-1 © 2021 CERN, o he ATLAS Collabo a ion
pT>15 GeV and a pseudo apidi y jηj<1.37 o 1.52<
jηj<2.47. The la e selec ion e oes elec on candida es
passing h ough he ansi ion egion be ween he ba el and
end-cap elec omagne ic calo ime e s. Muon candida es a e
equi ed o pass he medium iden i ica ion equi emen [27]
and ha e a pT>10 GeV and jηj<2.5. Bo h he elec on
and muon candida es mus sa is y he igh isola ion
equi emen [20,27], which is in ended o ejec misiden i-
ied candida es p oduced om he had oniza ion o qua ks
o gluons based on acks and clus e s econs uc ed
collinea o he candida es. E en s wi h exac ly one elec on
and one muon candida e a e selec ed wi h he equi emen
ha he lep on wi h highe ans e se momen um has a
pT>27 GeV. This selec ion lies abo e he h eshold o
cons an e iciency o bo h single-lep on igge selec ions.
E en s wi h same- la o lep on pai s a e ejec ed, in o de
o educe he backg ound om Z→ll decays. E en s
wi h a leading-pTelec on a e used in he sea ch o Z→
eτdecays (eτμchannel), while hose wi h a leading-pT
muon a e used in he sea ch o Z→μτ decays (μτe
channel), assuming he p omp lep on om he Z-boson
decay is he leading one in pT. In he μτechannel, he
a io o he elec on’spT econs uc ed in he inne
acking de ec o o he ans e se ene gy econs uc ed
in he elec omagne ic calo ime e , p ack
TðeÞ=ETclus e ðeÞ,is
equi ed o be smalle han 1.1 in o de o ejec Z→μμ
e en s. Opposi e-cha ge lep on-pai e en s a e analyzed in
he sea ch o signal e en s, while e en s wi h same-cha ge
lep on pai s a e used o es ima es o backg ound p oc-
esses. Qua k- o gluon-ini ia ed pa icle showe s (je s) a e
econs uc ed using he an i-k algo i hm [22,23] wi h a
adius pa ame e R¼0.4. Je s ul illing pT>20 GeV and
jηj<2.5a e iden i ied as con aining bhad ons i agged by
a dedica ed mul i a ia e algo i hm [28]. To ensu e he
samples o selec ed e en s do no o e lap wi h hose used
in he lτhad channel, e en s wi h a τhad- is candida e a e
e oed. The τhad- is candida es econs uc ed om je s wi h
apT>10 GeV and wi h one o h ee associa ed acks a e
selec ed in jηj<1.37 o 1.52 <jηj<2.5.Theτhad- is
iden i ica ion is pe o med by a ecu en neu al ne wo k
algo i hm [25].Aτhad- is candida e is equi ed o ha e a
pT>25 GeV and pass he igh iden i ica ion selec ion.
The missing ans e se momen um (Emiss
T) is calcula ed as
he nega i e pTsum o all ully econs uc ed and calib a ed
physics objec s [29,30]. Addi ionally, he calcula ion
includes inne de ec o acks ha o igina e om he e ex
associa ed wi h he ha d-sca e ing p ocess bu a e no
associa ed wi h any o he econs uc ed objec s.
The Z→lτ→ll0þ2νsignal e en s a e cha ac e ized
by a inal s a e which has wo ligh cha ged lep ons wi h
di e en la o and opposi e elec ic cha ge, wo neu inos,
and an in a ian mass o all hese pa icles compa ible wi h
he Z-boson mass. In mos cases, hese wo lep ons a e
emi ed app oxima ely back- o-back in he plane ans e se
o he p o on beam di ec ion. Since he τlep on is ypically
boos ed due o he la ge di e ence be ween i s mass and he
mass o i s pa en Zboson, he wo neu inos om i s decay
a e usually almos collinea wi h he cha ged lep on om
he τ-lep on decay. The dominan backg ound con ibu ion
is om he lep on- la o -conse ing Z→ττ →ll0þ4ν
decays, whe e he wo τlep ons decay lep onically.
Subleading backg ound con ibu ions om o he SM p oc-
esses wi h inal s a es wi h wo p omp lep ons include he
decays o a op-an i op-qua k pai ( ¯
), wo gauge bosons
(diboson), o a Higgs boson. Finally, small backg ound
con ibu ions come om Z→ll decays, whe e one o he
ligh cha ged lep ons is misiden i ied wi h he w ong la o ,
and e en s wi h “ ake lep ons.”The la e ype o back-
g ound e en s includes mos ly Wð→lνÞþje s e en s wi h
lep ons om hea y- la o qua k decays o wi h ligh -
qua k-ini ia ed je s ha a e misiden i ied as elec ons o
muons. The signal and backg ound e en s a e sepa a ed by
using a se o selec ion c i e ia ha de ine a signal-
enhanced sample, e e ed o as he signal egion (SR).
The selec ion c i e ia a e lis ed in Table I. Th ee neu al
ne wo k (NN) bina y classi ie s simila o hose used in
TABLE I. Selec ion c i e ia o e en s in he signal egion. The in a ian ans e se mass o land Emiss
Tis de ined as
mTðl;Emiss
TÞ¼ ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
2pTðlÞEmiss
T½1−cosðϕl−ϕEmiss
TÞ
q.
Selec ion c i e ion Pu pose
Exac ly wo isola ed ligh lep ons ðl0;l1Þwi h opposi e elec ic
cha ge and di e en la o (eo μ); pTðl0Þ>p
Tðl1Þ
Selec e en s consis en wi h signal decays.
No τhad- is candida e Complemen a i y o he lτhad channel.
T ans e se mass mTðl1;Emiss
TÞ<35 GeV
Rejec op-qua k and diboson e en s.
jΔϕðl0;Emiss
TÞj >1 ad
No b- agged je s (using he 77% e iciency wo king poin [28])
In a ian mass o he l0-l1pai mðl0;l1Þ>40 GeV Rejec e en s incompa ible wi h Z-boson decays.
Neu al ne wo k (op imized o signal s Z→ττ) ou pu >0.2Complemen a i y o he CRZττ egion.
In μτechannel: p ack
TðeÞ=Eclus e
TðeÞ<1.1Rejec Z→μμ e en s.
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
271801-2
Re . [9] a e ained on simula ed e en s o dis inguish
signal e en s om Z→ττ, op-qua k pai , and diboson
backg ound e en s indi idually. The inpu o hese NNs is
a mix u e o low- and high-le el kinema ic a iables,
ollowing he same s a egy as in he lτhad channel [9].
The low-le el a iables a e he momen um componen s o
he econs uc ed elec on and muon candida es, and he
Emiss
T. The high-le el a iables a e kinema ic p ope ies o
he e-μ-Emiss
Tsys em, such as he collinea mass mcollðe; μÞ,
de ined as he in a ian mass o he e-μ-2νsys em, whe e
he wo neu inos a e assumed o ha e a ec o ial momen-
um sum ha is equal in pTand he azimu hal angle ϕ
a ound he beam axis o he measu ed Emiss
Tand equal in η
o he subleading-pTlep on momen um. The ou pu s o he
indi idual NNs (NNiwi h alues be ween ze o and one) a e
combined in o a inal disc iminan as shown in Eq. (1),
he ea e e e ed o as he “combined NN ou pu ”:
combined NN ou pu ¼1−
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
1
3X
3
i¼1ð1−NNiÞ2
u
u
:ð1Þ
E en s classi ied by he NN ained o Z→ττ as back-
g oundlike a e excluded om he SR and used in a con ol
egion o be e de e mine he Z→ττ backg ound in he
maximum-likelihood i (see Table I). The signal accep-
ance in he SR is 19.5% o he eτμchannel and 11.2% o
he μτechannel, as de e mined om simula ed signal
samples. The lowe accep ance in he μτechannel is due
o he highe pT h eshold on he subleading-pTlep on and
he addi ional selec ion on p ack
T=Eclus e
T.
P edic ions o signal and backg ound con ibu ions a e
based pa ly on Mon e Ca lo (MC) simula ions and pa ly
on es ima es om da a. Signal and backg ound p ocesses
we e simula ed as in Re . [9]. The signal e en s we e
simula ed using
PYTHIA
8[32] wi h ma ix elemen s calcu-
la ed a leading o de (LO) in he s ong coupling cons an .
Nominal signal samples we e gene a ed wi h a pa i y-
conse ing Zlτ e ex and unpola ized τlep ons. Scena ios
whe e he decays a e maximally pa i y iola ing we e
conside ed by eweigh ing he simula ed e en s using
TAUSPINNER
[33], as discussed in Re . [9]. The Z→ττ
backg ound e en s we e simula ed wi h he
SHERPA
2.2.1
[34] gene a o using he NNPDF 3.0 NNLO PDF se [35]
and nex - o-leading-o de (NLO) ma ix elemen s o up o
wo pa ons, and LO ma ix elemen s o up o ou pa ons,
calcula ed wi h he
COMIX
[36] and
OPENLOOPS
[37–39]
lib a ies. Backg ound Z→ll e en s we e simula ed using
he
POWHEG
-
BOX
[40] gene a o wi h NLO ma ix ele-
men s. All MC samples include a de ailed simula ion o he
ATLAS de ec o wi h
GEANT
[41,42]. As in Re . [9], he
simula ion o Z-boson p oduc ion is imp o ed h ough a
co ec ion de i ed om measu emen s in da a. The simu-
la ed pTspec a o he Zboson a e eweigh ed o ma ch he
un olded dis ibu ion measu ed by ATLAS in Re . [43].
The p edic ed o e all yields o signal and Z→ττ e en s
a e de e mined by a binned maximum-likelihood i o he
combined da a in he SR and in a con ol egion enhanced
in Z→ττ e en s (CRZττ). This elimina es he heo e ical
unce ain ies in he o al Z-boson p oduc ion c oss sec ion
(σZ), as well as he expe imen al unce ain ies ela ed o he
accep ance o he common ll0 inal s a e. The selec ion
c i e ia o e en s in he CRZττ a e he same as hose o
e en s in he SR, excep ha e en s a e equi ed o be
classi ied as Z→ττ-like, i.e., wi h an ou pu smalle han
0.2 o he Z→ττ NN and g ea e han 0.2 o bo h he op-
qua k and diboson NNs. In he μτechannel, a small
con ibu ion o he o al backg ound o igina es om Z→
μμ e en s in which one muon is mis econs uc ed as an
elec on. Such elec on candida es may o igina e om
muons ha ail he muon selec ion equi emen s and whose
acks a e associa ed wi h a calo ime e ene gy clus e and
econs uc ed as elec ons. They may also o igina e om
muons unde going b emss ahlung. Such e en s a e mod-
eled wi h simula ion and hei p edic ed yield is based on
he measu ed σZ[44]. The modeling is alida ed in a
dedica ed egion which has he same selec ion as he μτe
SR excep o he in e se selec ion on p ack
TðeÞ=Eclus e
TðeÞ.
Based on he obse ed le el o ag eemen be ween da a and
simula ion, a sys ema ic unce ain y o 15% is assigned o
he p edic ed yield o Z→μμ e en s in he SR, wi h no
u he co ec ion.
E en s wi h ake lep ons yield a small bu s ill signi ican
backg ound con ibu ion. In mos cases, he ake lep on
is he subleading one. These e en s a e es ima ed om
da a using a “ ake- ac o me hod”simila o he one
used in Re . [9]. The ake ac o is de ined as he a io
Npass-iso
ake =N ail-iso
ake , whe e “ ake”indica es e en s wi h a leas
one ake lep on and “pass-iso”o “ ail-iso”indica e
whe he he subleading lep on passes o ails he isola ion
equi emen . The ake ac o is measu ed in e en s wi h
pai s o same-sign lep ons (SS). These e en s a e enhanced
in Wð→lνÞþje s, which is he dominan sou ce o e en s
wi h ake lep ons in he SR. E en s in he SS egion pass
he same e en selec ions as hose in he SR excep o a
same-cha ge equi emen . The ake ac o s a e measu ed as
unc ions o he ans e se momen um and pseudo apidi y
o he lep ons, sepa a ely o eτμand μτee en s. The
kinema ic p ope ies o e en s wi h ake lep ons in he SR
o in he CRs a e es ima ed by he dis ibu ions o e en s
wi h he subleading lep on ailing he isola ion equi emen ,
bu o he wise sa is ying all o he selec ion c i e ia o ha
egion, mul iplied by he ake ac o . The o al p edic ed
yields o he e en s wi h ake lep ons in he SR and CRs a e
ins ead de e mined by a combined maximum-likelihood i
o da a, sepa a ely o eτμand μτee en s. The emaining
backg ound p ocesses a e es ima ed using simula ions.
These backg ounds include e en s om he p oduc ion
and decay o op qua ks [32,40], pai s o gauge bosons
[34,35], and he Higgs boson [32,40]. The yield o he
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
271801-3
e en s wi h op qua ks is de e mined in he maximum-
likelihood i o da a ia he inclusion o a op-qua k con ol
egion (CRTop). The selec ion equi emen s o he CRTop
a e he same as o he SR excep ha a leas one b- agged
je is equi ed. The expec ed e en yields o he emaining
p ocesses a e de e mined based on hei p oduc ion c oss
sec ion, he in eg a ed luminosi y, and he simula ed selec-
ion e iciency.
A s a is ical analysis o he selec ed e en s is pe o med
o assess he p esence o signal e en s, ollowing he same
me hod used in Re . [9]. A simul aneous binned maximum-
likelihood i o he combined NN ou pu dis ibu ion in he
SR, he mcollðe; μÞdis ibu ion in he CRZττ, and he e en
yield in CRTop is used o cons ain unce ain ies in he
p edic ions and ex ac e idence o a possible signal. The i
is pe o med independen ly o he eτand μτ channels. The
ac ion o Z→eτe en s selec ed in he μτ channel (and
ice e sa) is negligible and is he e o e neglec ed. In o de
o imp o e he disc imina ion be ween signal and he
e en s wi h ake lep ons, he e en s in he SR a e u he
spli in o wo egions based on he ans e se momen um o
he subleading-pTlep on l1. The low-pTSR con ains
e en s wi h a pTðl1Þ<20ð25ÞGeV in he eτμ(μτe)
channel, while he high-pTSR con ains he e en s abo e
hese h esholds. Bo h SRs in he eτμchannel ha e
compa able sensi i i y, while he low-pTSR in he μτe
channel is mo e sensi i e han he high-pTSR. Bo h SRs
a e i ed simul aneously. The e a e ou uncons ained
pa ame e s in he i s: he pa ame e o in e es de e mines
he LFV b anching ac ion BðZ→lτÞby modi ying an
a bi a y p e i signal yield, μZde e mines σZ imes he
o e all accep ance and econs uc ion e iciency o he ll0
inal s a e in Z→ττ and signal e en s, μ op de e mines he
yield o he op-qua k e en s, and μ akes de e mines he
yield o he e en s wi h ake lep ons. Cons ained pa am-
e e s a e also in oduced o accoun o sys ema ic unce -
ain ies in he signal and backg ound p edic ions, as in
Re . [9]. These include unce ain ies in simula ed e en s in
he modeling o igge , econs uc ion, iden i ica ion and
isola ion e iciencies, as well as ene gy calib a ions and
esolu ions o econs uc ed objec s. No sys ema ic unce -
ain ies a e assigned o he o e all yields o e en s wi h Z-
boson decays, ake lep ons, o op qua ks as hese yields a e
de e mined om da a. Unce ain ies ela ed o e en s wi h
ake lep ons include s a is ical unce ain ies due o he size
o he da a sample used o measu e he ake ac o s as well
as o model hei dis ibu ions in he SRs and CRs.
Sys ema ic unce ain ies assigned o e en s wi h ake
lep ons accoun o : shape di e ences in he modeling o
he combined NN ou pu in he SS e en s; di e ences in he
composi ion o he e en s wi h ake lep ons be ween SS
e en s and he e en s in he SRs; and unce ain ies a ec ing
he numbe o e en s wi h p omp lep ons ailing he
isola ion equi emen s as es ima ed by simula ion. The
dominan unce ain ies o he sea ch a e s a is ical in na u e.
Among he sys ema ic unce ain ies, he dominan ones a e
hose in he je calib a ion which en e h ough he
calcula ion o he Emiss
T[24]. A summa y o he unce ain-
ies and hei impac on he LFV b anching ac ion is gi en
in Table II.
The obse ed and bes - i p edic ed dis ibu ions o he
combined NN ou pu in he SRs wi h he highes sensi i i y
as well as dis ibu ions o he collinea mass in he high-pT
SRs a e shown in Fig. 1. The bes - i yield o Z→lτsignal
co esponds o he b anching ac ions BðZ→eτÞ¼
½−2.63.5ðs a Þ2.7ðsys Þ×10−6and BðZ→μτÞ¼
½−4.43.9ðs a Þ3.4ðsys Þ×10−6. The bes - i yields
o Z→ττ, op qua ks, and e en s wi h ake lep ons a e
close o he p e i p edic ed alues and a e de e mined wi h
a ela i e p ecision o 2%–4%, excep he e en s wi h ake
lep ons in he μτechannel, which ha e an unce ain y o
30%. As no signi ican excess o da a o e he p edic ed
backg ound is obse ed, a combined i o he lτl0and
lτhad channels is used o se uppe limi s on BðZ→lτÞ.
The analysis o he lτhad channel wi h Run 2 da a [9] uses
a simila scheme o egions and uncons ained pa ame e s.
In he s a is ical combina ion, he pa ame e s o in e es a e
co ela ed among he di e en SRs and CRs. The o he
uncons ained pa ame e s a e unco ela ed as hese accoun
ei he o backg ounds speci ic o each channel o o di -
e en accep ances o he lτl0o lτhad inal s a es. Common
sys ema ic unce ain ies a e co ela ed, besides hose ela-
ed o he je ene gy calib a ions, which a e unco ela ed.
TABLE II. Summa y o he con ibu ions o he unce ain y in
he measu ed BðZ→lτl0Þ. The unce ain ies ela ed o ligh
cha ged lep ons include hose in he igge , econs uc ion,
iden i ica ion, and isola ion e iciencies, as well as ene gy
calib a ions. The unce ain ies ela ed o je s and Emiss
Tinclude
hose in he ene gy calib a ion and esolu ion. The unce ain y in
he Z→μμ yield is only applicable in he μτ channel. The o al
sys ema ic unce ain y can di e om he sum in quad a u e o
he di e en con ibu ions due o co ela ions among unce ain-
ies as a esul o he likelihood i o da a.
Unce ain y in BðZ→lτÞ[×10−6]
Sou ce o unce ain y eτμτ
S a is ical 3.53.9
Fake lep ons (s a is ical) 0.10.1
Sys ema ic 2.73.4
Ligh cha ged lep ons 0.40.4
Emiss
T0.40.8
Je s 1.92.2
Fla o agging 0.50.9
Z-boson modeling <0.10.1
Z→μμ yield 0.8
O he backg ounds 0.10.6
Fake lep ons (sys ema ic) 0.40.9
To al 4.45.2
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
271801-4
This conse a i e co ela ion scheme was chosen because
o di e en bes - i alues o he pa ame e s associa ed
wi h hese unce ain ies in he wo channels. Howe e ,
he i wi h co ela ed je ene gy calib a ion unce ain ies
yields compa ible combined uppe limi s. The analysis o
he lτhad channel wi h Run 1 da a is combined using
he same co ela ion scheme as in Re . [9]. The combined
bes - i amoun o Z→lτsignal co esponds o he
b anching ac ions BðZ→eτÞ¼½−1.42.5ðs a Þ
1.8ðsys Þ×10−6and BðZ→μτÞ¼½1.72.2ðs a Þ
1.6ðsys Þ×10−6.
Since no signi ican de ia ion om he SM backg ound
hypo hesisisobse ed,exclusionlimi sa e se using heCLS
me hod [45]. The uppe limi s a e shown in Table III o LFV
0
500
1000
1500
2000
2500
3000
3500
E en s / 0.025
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τ
e→Z
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τ
e→Z
ATLAS
-1
= 13 TeV, 139 bs
μ
τ
e SR,
T
pLow-
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
Combined NN ou pu
0.75
0.875
1
1.125
1.25
Da a / p ed.
(a)
0
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
2400
E en s / 0.025
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τμ
→Z
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τμ
→Z
ATLAS
-1
= 13 TeV, 139 bs
e
τμ
SR,
T
pHigh-
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
Combined NN ou pu
0.75
0.875
1
1.125
1.25
Da a / p ed.
(b)
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
E en s / 10 GeV
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τ
e→Z
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τ
e→Z
ATLAS
-1
= 13 TeV, 139 bs
μ
τ
e SR,
T
pHigh-
60 70 80 90 100 110 120 130 140 150 160
) [GeV]e,
μ
(
coll
m
0.75
0.875
1
1.125
1.25
Da a / p ed.
(c)
0
2000
4000
6000
8000
10000
E en s / 10 GeV
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τμ
→Z
Da a
Fake lep on
ττ→Z
ll→Z
Top qua k
Diboson
Higgs
)
-4
10×=3B (
τμ
→Z
ATLAS
-1
= 13 TeV, 139 bs
e
τμ
SR,
T
pHigh-
60 70 80 90 100 110 120 130 140 150 160
) [GeV]
μ
,e(
coll
m
0.75
0.875
1
1.125
1.25
Da a / p ed.
(d)
FIG. 1. Obse ed and bes - i p edic ed dis ibu ions in he SRs. Dis ibu ions o he combined NN ou pu a e shown in (a) o he low-
pTSR o he eτμchannel, and in (b) o he high-pTSR o he μτechannel. Dis ibu ions o he collinea mass in he high-pTSR a e
shown in (c) and (d) o he eτμand μτechannels, espec i ely. The expec ed signal, no malized o an a bi a y BðZ→lτÞ¼3×10−4
o isualiza ion pu poses, is shown as a dashed his og am in each plo . In he panel below each plo , he a ios o he obse ed yield
(do s) and he bes - i backg ound-plus-signal yield (solid line) o he bes - i backg ound yield a e shown. The ha ched unce ain y
bands ep esen one s anda d de ia ion o he combined s a is ical and sys ema ic unce ain ies. The i s and las bins in each plo
include unde low and o e low e en s, espec i ely.
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
271801-5

decays wi h di e en assump ions abou he τ-pola iza ion
s a e. The pola iza ion o he τlep on a ec s he ene gy o i s
isible decay p oduc s and hus he accep ance o signal
e en s. In he scena io whe e he τlep ons a e unpola ized,
he obse ed uppe limi s a 95% C.L. on BðZ→eτÞand
BðZ→μτÞa e 5.0×10−6and 6.5×10−6, espec i ely.
In conclusion, his Le e epo s he i s analysis o he
lτl0channel in he sea ch o Z→lτdecays a he LHC.
This channel yields a sensi i i y simila o he lτhad channel.
Wi h he combined esul s o he wo channels, he ATLAS
expe imen se s he mos s ingen cons ain s on LFV Z-
boson decays in ol ing τlep ons o da e. The p ecision o
hese esul s is mainly limi ed by s a is ical unce ain ies.
We hank CERN o he e y success ul ope a ion o he
LHC, as well as he suppo s a om ou ins i u ions
wi hou whom ATLAS could no be ope a ed e icien ly.
We acknowledge he suppo o ANPCyT, A gen ina;
Ye PhI, A menia; ARC, Aus alia; BMWFW and FWF,
Aus ia; ANAS, Aze baijan; SSTC, Bela us; CNPq and
FAPESP, B azil; NSERC, NRC and CFI, Canada; CERN;
ANID, Chile; CAS, MOSTand NSFC, China; Minciencias,
Colombia; MSMT CR, MPO CR and VSC CR, Czech
Republic; DNRF and Danish Na u al Science Resea ch
Council, Denma k; IN2P3-CNRS and CEA-DRF/IRFU,
F ance; Sho a Rus a eli Na ional Science Founda ion o
Geo gia, Geo gia; BMBF, HGF and MPG, Ge many;
Gene al Sec e a ia o Resea ch and Inno a ion, G eece;
RGC and Hong Kong SAR, China; ISF and Benoziyo
Cen e , Is ael; INFN, I aly; MEXT and JSPS, Japan;
CNRST, Mo occo; NWO, Ne he lands; Resea ch
Council o No way, No way; MNiSW and NCN,
Poland; FCT, Po ugal; MNE/IFA, Romania; JINR;
Minis y o Educa ion and Science o he Russian
Fede a ion and NRC KI, Russian Fede a ion; Minis y o
Educa ion, Science and Technological De elopmen ,
Se bia; Minis y o Educa ion, Science, Resea ch and
Spo , Slo akia; ARRS and Minis y o Educa ion,
Science and Spo , Slo enia; DSI/NRF, Sou h A ica;
MICINN, Spain; Swedish Resea ch Council and
Wallenbe g Founda ion, Sweden; Sec e a ia o
Educa ion and Resea ch, Swi ze land, SNSF and
Can ons o Be n and Gene a, Swi ze land; MOST,
Taiwan; TAEK, Tu key; STFC, Uni ed Kingdom; DOE
and NSF, USA In addi ion, indi idual g oups and membe s
ha e ecei ed suppo om BCKDF, CANARIE, Compu e
Canada and CRC, Canada; COST, ERC, ERDF, Ho izon
2020 and Ma ie Skłodowska-Cu ie Ac ions, Eu opean
Union; In es issemen s d’A eni Labex, In es issemen s
d’A eni Idex and ANR, F ance; DFG and A H
Founda ion, Ge many; He aklei os, Thales and A is eia
p og ammes co- inanced by EU-ESF and
he He aklei os, Thales and A is eia p og ammes co-
inanced by EU-ESF and he G eek NSRF, G eece;
BSF-NSF and GIF, Is ael; No wegian Financial
Mechanism 2014-2021, No way; La Caixa Banking
Founda ion, CERCA P og amme Gene ali a de
Ca alunya and PROMETEO and GenT P og ammes
Gene ali a Valenciana, Spain; Gö an Gus a ssons
S i else, Sweden; The Royal Socie y and Le e hulme
T us , Uni ed Kingdom. The c ucial compu ing suppo
om all WLCG pa ne s is acknowledged g a e ully, in
pa icula om CERN, he ATLAS Tie -1 acili ies a
TRIUMF (Canada), NDGF (Denma k, No way,
Sweden), CC-IN2P3 (F ance), KIT/G idKA (Ge many),
INFN-CNAF (I aly), NL-T1 (Ne he lands), PIC (Spain),
ASGC (Taiwan), RAL (UK) and BNL (USA), he Tie -2
acili ies wo ldwide and la ge non-WLCG esou ce p o-
ide s. Majo con ibu o s o compu ing esou ces a e
lis ed in Re . [46].
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J. A. Apa isi Pozo,169 M. A. Apa o,152 L. Ape io Bella,44 N. A anzabal,34 V. A aujo Fe az,78a C. A cangele i,49
A. T. H. A ce,47 E. A ena,88 J-F. A guin,107 S. A gy opoulos,50 J.-H. A ling,44 A. J. A mb us e ,34 A. A ms ong,166
O. A naez,162 H. A nold,34 Z. P. A uba ena Tame,111 G. A oni,130 H. Asada,113 K. Asai,122 S. Asai,159 N. A. Asbah,57
E. M. Asimakopoulou,167 L. Asqui h,152 J. Assahsah,33d K. Assamagan,27 R. As alos,26a R. J. A kin,31a M. A kinson,168
N. B. A lay,17 H. A mani,58b P. A. A masiddha,103 K. Augs en,137 S. Au icchio,67a,67b V. A. Aus up,177 G. A ne ,156
G. A olio,34 M. K. Ayoub,13c G. Azuelos,107,e D. Babal,26a H. Bachacou,140 K. Bachas,158 F. Backman,43a,43b A. Badea,57
P. Bagnaia,70a,70b H. Bah asemani,148 A. J. Bailey,169 V. R. Bailey,168 J. T. Baines,139 C. Bakalis,9O. K. Bake ,178
P. J. Bakke ,116 E. Bakos,14 D. Bakshi Gup a,7S. Balaji,153 R. Balasub amanian,116 E. M. Baldin,118b,118a P. Balek,138
E. Ballabene,66a,66b F. Balli,140 W. K. Balunas,130 J. Balz,97 E. Banas,82 M. Bandie amon e,134 A. Bandyopadhyay,17
L. Ba ak,157 E. L. Ba be io,102 D. Ba be is,53b,53a M. Ba be o,99 G. Ba bou ,92 K. N. Ba ends,31a T. Ba illa i,112
M-S. Ba isi s,34 J. Ba keloo,127 T. Ba klow,149 B. M. Ba ne ,139 R. M. Ba ne ,16 A. Ba oncelli,58a G. Ba one,27 A. J. Ba ,130
L. Ba anco Na a o,43a,43b F. Ba ei o,96 J. Ba ei o Guima ães da Cos a,13a U. Ba on,157 S. Ba so ,133 F. Ba els,59a
R. Ba oldus,149 G. Ba olini,99 A. E. Ba on,87 P. Ba os,26a A. Basalae ,44 A. Basan,97 I. Bash a,72a,72b A. Bassala ,62
M. J. Basso,162 C. R. Basson,98 R. L. Ba es,55 S. Ba lamous,33e J. R. Ba ley,30 B. Ba ool,147 M. Ba aglia,141 M. Bauce,70a,70b
F. Baue ,140,a P. Baue ,22 H. S. Bawa,29 A. Bayi li,11c J. B. Beacham,47 T. Beau,131 P. H. Beauchemin,165 F. Beche e ,50
P. Bech le,22 H. P. Beck,18, K. Becke ,173 C. Beco ,44 A. J. Beddall,11a V. A. Bednyako ,77 C. P. Bee,151 T. A. Bee mann,177
M. Begalli,78b M. Begel,27 A. Behe a,151 J. K. Beh ,44 C. Bei ao Da C uz E Sil a,34 J. F. Bei e ,51,34 F. Beisiegel,22
M. Bel ki ,4G. Bella,157 L. Bellagamba,21b A. Belle i e,32 P. Bellos,19 K. Belobo odo ,118b,118a K. Belo skiy,109
N. L. Belyae ,109 D. Benchek oun,33a Y. Benhammou,157 D. P. Benjamin,27 M. Benoi ,27 J. R. Bensinge ,24 S. Ben elsen,116
L. Be es o d,34 M. Be e a,49 D. Be ge,17 E. Be geaas Kuu mann,167 N. Be ge ,4B. Be gmann,137 L. J. Be gs en,24
J. Be inge ,16 S. Be lendis,6G. Be na di,131 C. Be nius,149 F. U. Be nlochne ,22 T. Be y,91 P. Be a,44 A. Be hold,46
I. A. Be am,87 O. Bessidskaia Bylund,177 S. Be hke,112 A. Be i,40 A. J. Be an,90 S. Bha a,151 D. S. Bha acha ya,172
P. Bha a ai,24 V. S. Bhopa ka ,5R. Bi,134 R. M. Bianchi,134 O. Biebel,111 R. Bielski,34 N. V. Biesuz,69a,69b M. Biglie i,72a
T. R. V. Billoud,137 M. Bindi,51 A. Bingul,11d C. Bini,70a,70b S. Biondi,21b,21a C. J. Bi ch-sykes,98 G. A. Bi d,19,139
M. Bi man,175 T. Bisanz,34 J. P. Biswal,2D. Biswas,176,g A. Bi adze,98 C. Bi ich,46 K. Bjø ke,129 I. Bloch,44 C. Blocke ,24
A. Blue,55 U. Blumenschein,90 J. Blumen hal,97 G. J. Bobbink,116 V. S. Bob o niko ,118b,118a D. Boga ac,12
A. G. Bogdanchiko ,118b,118a C. Bohm,43a V. Bois e ,91 P. Bokan,44 T. Bold,81a M. Bomben,131 M. Bona,90
M. Boonekamp,140 C. D. Boo h,91 A. G. Bo b´ely,55 H. M. Bo ecka-Bielska,107 L. S. Bo gna,92 G. Bo isso ,87
D. Bo ole o,130 D. Bosche ini,21b M. Bosman,12 J. D. Bossio Sola,101 K. Bouaouda,33a J. Boud eau,134
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
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E. V. Bouho a-Thacke ,87 D. Boumediene,36 R. Bouque ,131 A. Bo eia,123 J. Boyd,34 D. Boye,27 I. R. Boyko,77
A. J. Bozson,91 J. B acinik,19 N. B ahimi,58d,58c G. B and ,177 O. B and ,30 F. B a en,44 B. B au,100 J. E. B au,127
W. D. B eaden Madden,55 K. B endlinge ,44 R. B ene ,175 L. B enne ,34 R. B enne ,167 S. B essle ,175 B. B ickwedde,97
D. L. B iglin,19 D. B i on,55 D. B i zge ,112 I. B ock,22 R. B ock,104 G. B ooijmans,37 W. K. B ooks,142d E. B os ,27
P. A. B uckman de Rens om,82 B. B üe s,44 D. B uncko,26b A. B uni,21b G. B uni,21b M. B uschi,21b N. B uscino,70a,70b
L. B yngema k,149 T. Buanes,15 Q. Bua ,151 P. Buchholz,147 A. G. Buckley,55 I. A. Budago ,77 M. K. Bugge,129
O. Buleko ,109 B. A. Bulla d,57 T. J. Bu ch,117 S. Bu din,88 C. D. Bu ga d,44 A. M. Bu ge ,125 B. Bu ghg a e,7J. T. P. Bu ,44
C. D. Bu on,10 J. C. Bu zynski,100 V. Büsche ,97 P. J. Bussey,55 J. M. Bu le ,23 C. M. Bu a ,55 J. M. Bu e wo h,92
W. Bu inge ,139 C. J. Buxo Vazquez,104 A. R. Buzykae ,118b,118a G. Cab as,21b,21a S. Cab e a U bán,169 D. Ca o io,54
H. Cai,134 V. M. M. Cai o,149 O. Caki ,3a N. Calace,34 P. Cala iu a,16 G. Calde ini,131 P. Cal ayan,63 G. Callea,55
L. P. Caloba,78b A. Cal abiano,71a,71b S. Cal en e Lopez,96 D. Cal e ,36 S. Cal e ,36 T. P. Cal e ,99 M. Cal e i,69a,69b
R. Camacho To o,131 S. Cama da,34 D. Cama e o Munoz,96 P. Cama i,71a,71b M. T. Came lingo,72a,72b D. Came on,129
C. Caminche ,171 M. Campanelli,92 A. Camplani,38 V. Canale,67a,67b A. Canesse,101 M. Cano B e ,75 J. Can e o,125 Y. Cao,168
M. Capua,39b,39a A. Ca bone,66a,66b R. Ca da elli,71a F. Ca dillo,169 G. Ca ducci,39b,39a T. Ca li,34 G. Ca lino,67a
B. T. Ca lson,134 E. M. Ca lson,171,163a L. Ca mina i,66a,66b M. Ca nesale,70a,70b R. M. D. Ca ney,149 S. Ca on,115
E. Ca quin,142d S. Ca á,44 G. Ca a a,21b,21a J. W. S. Ca e ,162 T. M. Ca e ,48 D. Casadei,31c M. P. Casado,12,h
A. F. Casha,162 E. G. Cas iglia,178 F. L. Cas illo,59a L. Cas illo Ga cia,12 V. Cas illo Gimenez,169 N. F. Cas o,135a,135e
A. Ca inaccio,34 J. R. Ca mo e,129 A. Ca ai,34 V. Ca alie e,27 N. Ca alli,21b,21a V. Ca asinni,69a,69b E. Celebi,11b F. Celli,130
K. Ce ny,126 A. S. Ce quei a,78a A. Ce i,152 L. Ce i o,71a,71b F. Ce u i,16 A. Ce elli,21b,21a S. A. Ce in,11b Z. Chadi,33a
D. Chak abo y,117 M. Chala,135 J. Chan,176 W. S. Chan,116 W. Y. Chan,88 J. D. Chapman,30 B. Cha geish ili,155b
D. G. Cha l on,19 T. P. Cha man,90 M. Cha e jee,18 C. C. Chau,32 S. Chekano ,5S. V. Chekulae ,163a G. A. Chelko ,77,i
A. Chen,103 B. Chen,157 C. Chen,58a C. H. Chen,76 H. Chen,13c H. Chen,27 J. Chen,58a J. Chen,37 J. Chen,24 S. Chen,132
S. J. Chen,13c X. Chen,13b Y. Chen,58a Y-H. Chen,44 C. L. Cheng,176 H. C. Cheng,60a H. J. Cheng,13a A. Cheplako ,77
E. Che emushkina,44 R. Che kaoui El Mou sli,33e E. Cheu,6K. Cheung,61 L. Che alie ,140 V. Chia ella,49 G. Chia elli,69a
G. Chiodini,65a A. S. Chisholm,19 A. Chi an,25b I. Chiu,159 Y. H. Chiu,171 M. V. Chizho ,77,j K. Choi,10 A. R. Chomon ,70a,70b
Y. Chou,100 Y. S. Chow,116 L. D. Ch is ophe ,31 M. C. Chu,60a X. Chu,13a,13d J. Chudoba,136 J. J. Chwas owski,82 D. Cie i,112
K. M. Ciesla,82 V. Cind o,89 I. A. Cioa ă,25b A. Ciocio,16 F. Ci o o,67a,67b Z. H. Ci on,175,k M. Ci e io,66a D. A. Ciubo a u,25b
B. M. Ciungu,162 A. Cla k,52 P. J. Cla k,48 J. M. Cla ijo Columbie,44 S. E. Clawson,98 C. Clemen ,43a,43b L. Clissa,21b,21a
Y. Coadou,99 M. Cobal,64a,64c A. Cocca o,53b J. Coch an,76 R. F. Coelho Ba ue,135a R. Coelho Lopes De Sa,100 S. Coelli,66a
H. Cohen,157 A. E. C. Coimb a,34 B. Cole,37 J. Collo ,56 P. Conde Muiño,135a,135h S. H. Connell,31c I. A. Connelly,55
E. I. Con oy,130 F. Con en i,67a,l H. G. Cooke,19 A. M. Coope -Sa ka ,130 F. Co mie ,170 L. D. Co pe,34 M. Co adi,70a,70b
E. E. Co igan,94 F. Co i eau,101,m M. J. Cos a,169 F. Cos anza,4D. Cos anzo,145 B. M. Co e,123 G. Cowan,91 J. W. Cowley,30
J. C ane,98 K. C anme ,121 R. A. C eage ,132 S. C ´ep´e-Renaudin,56 F. C escioli,131 M. C is inziani,147 M. C is o o e i,73a,73b,n
V. C o ,165 G. C ose i,39b,39a A. Cue o,4T. Cuhada Donszelmann,166 H. Cui,13a,13d A. R. Cukie man,149
W. R. Cunningham,55 S. Czekie da,82 P. Czod owski,34 M. M. Czu ylo,59b M. J. Da Cunha Sa gedas De Sousa,58a
J. V. Da Fonseca Pin o,78b C. Da Via,98 W. Dab owski,81a T. Dado,45 S. Dahbi,31 T. Dai,103 C. Dallapiccola,100 M. Dam,38
G. D’amen,27 V. D’Amico,72a,72b J. Damp,97 J. R. Dandoy,132 M. F. Dane i,28 M. Danninge ,148 V. Dao,34 G. Da bo,53b
S. Da mo a,5A. Da agup a,127 S. D’Au ia,66a,66b C. Da id,163b T. Da idek,138 D. R. Da is,47 B. Da is-Pu cell,32
I. Dawson,90 K. De,7R. De Asmundis,67a M. De Beu s,116 S. De Cas o,21b,21a N. De G oo ,115 P. de Jong,116
H. De la To e,104 A. De Ma ia,13c D. De Pedis,70a A. De Sal o,70a U. De Sanc is,71a,71b M. De San is,71a,71b A. De San o,152
J. B. De Vi ie De Regie,56 D. V. Dedo ich,77 J. Degens,116 A. M. Deiana,40 J. Del Peso,96 Y. Delaba Diaz,44 F. Delio ,140
C. M. Deli zsch,6M. Della Pie a,67a,67b D. Della Volpe,52 A. Dell’Acqua,34 L. Dell’As a,66a,66b M. Delmas o,4
P. A. Delsa ,56 S. Deme s,178 M. Demiche ,77 S. P. Deniso ,119 L. D’E amo,117 D. De enda z,82 J. E. De kaoui,33d
F. De ue,131 P. De an,88 K. Desch,22 K. De e,162 C. Deu sch,22 P. O. De i ei os,34 F. A. Di Bello,70a,70b A. Di Ciaccio,71a,71b
L. Di Ciaccio,4C. Di Dona o,67a,67b A. Di Gi olamo,34 G. Di G ego io,69a,69b A. Di Luca,73a,73b B. Di Micco,72a,72b
R. Di Na do,72a,72b C. Diaconu,99 F. A. Dias,116 T. Dias Do Vale,135a M. A. Diaz,142a F. G. Diaz Cap iles,22 J. Dickinson,16
M. Didenko,169 E. B. Diehl,103 J. Die ich,17 S. Díez Co nell,44 C. Diez Pa dos,147 A. Dimi ie ska,16 W. Ding,13b
J. Ding elde ,22 I-M. Dinu,25b S. J. Di meie ,59b F. Di us,34 F. Djama,99 T. Djoba a,155b J. I. Dju sland,15
M. A. B. Do Vale,143a D. Dodswo h,24 C. Doglioni,94 J. Dolejsi,138 Z. Dolezal,138 M. Donadelli,78c B. Dong,58c J. Donini,36
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
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C. Zhu,13a,13d H. L. Zhu,58a H. Zhu,13a J. Zhu,103 Y. Zhu,58a X. Zhuang,13a K. Zhuko ,108 V. Zhulano ,118b,118a D. Zieminska,63
N. I. Zimine,77 S. Zimme mann,50,a M. Ziolkowski,147 L. Ži ko ić,14 A. Zoccoli,21b,21a K. Zoch,52 T. G. Zo bas,145
O. Zo mpa,42 W. Zou,37 and L. Zwalinski34
(ATLAS Collabo a ion)
1Depa men o Physics, Uni e si y o Adelaide, Adelaide, Aus alia
2Depa men o Physics, Uni e si y o Albe a, Edmon on AB, Canada
3aDepa men o Physics, Anka a Uni e si y, Anka a, Tu key
3bIs anbul Aydin Uni e si y, Applica ion and Resea ch Cen e o Ad anced S udies, Is anbul, Tu key
3cDi ision o Physics, TOBB Uni e si y o Economics and Technology, Anka a, Tu key
4LAPP, Uni . Sa oie Mon Blanc, CNRS/IN2P3, Annecy, F ance
5High Ene gy Physics Di ision, A gonne Na ional Labo a o y, A gonne, Illinois, USA
6Depa men o Physics, Uni e si y o A izona, Tucson, A izona, USA
7Depa men o Physics, Uni e si y o Texas a A ling on, A ling on, A ling on, Texas, USA
8Physics Depa men , Na ional and Kapodis ian Uni e si y o A hens, A hens, G eece
9Physics Depa men , Na ional Technical Uni e si y o A hens, Zog a ou, G eece
10Depa men o Physics, Uni e si y o Texas a Aus in, Aus in, Texas, USA
11aBahcesehi Uni e si y, Facul y o Enginee ing and Na u al Sciences, Is anbul, Tu key
11bIs anbul Bilgi Uni e si y, Facul y o Enginee ing and Na u al Sciences, Is anbul, Tu key
11cDepa men o Physics, Bogazici Uni e si y, Is anbul, Tu key
11dDepa men o Physics Enginee ing, Gazian ep Uni e si y, Gazian ep, Tu key
12Ins i u de Física d’Al es Ene gies (IFAE), Ba celona Ins i u e o Science and Technology, Ba celona, Spain
13aIns i u e o High Ene gy Physics, Chinese Academy o Sciences, Beijing, China
13bPhysics Depa men , Tsinghua Uni e si y, Beijing, China
13cDepa men o Physics, Nanjing Uni e si y, Nanjing, China
13dUni e si y o Chinese Academy o Science (UCAS), Beijing, China
14Ins i u e o Physics, Uni e si y o Belg ade, Belg ade, Se bia
15Depa men o Physics and Technology, Uni e si y o Be gen, Be gen, No way
16Physics Di ision, Law ence Be keley Na ional Labo a o y and Uni e si y o Cali o nia, Be keley, Cali o nia, USA
17Ins i u ü Physik, Humbold Uni e si ä zu Be lin, Be lin, Ge many
18Albe Eins ein Cen e o Fundamen al Physics and Labo a o y o High Ene gy Physics, Uni e si y o Be n, Be n, Swi ze land
19School o Physics and As onomy, Uni e si y o Bi mingham, Bi mingham, Uni ed Kingdom
20aFacul ad de Ciencias y Cen o de In es igaciónes, Uni e sidad An onio Na iño, Bogo á, Colombia
20bDepa amen o de Física, Uni e sidad Nacional de Colombia, Bogo á, Colombia, Colombia
21aDipa imen o di Fisica e As onomia A. Righi, Uni e si `a di Bologna, Bologna, I aly
21bINFN Sezione di Bologna, Bologna, I aly
22Physikalisches Ins i u , Uni e si ä Bonn, Bonn, Ge many
23Depa men o Physics, Bos on Uni e si y, Bos on, Massachuse s, USA
24Depa men o Physics, B andeis Uni e si y, Wal ham, Massachuse s, USA
25aT ansil ania Uni e si y o B aso , B aso , Romania
25bHo ia Hulubei Na ional Ins i u e o Physics and Nuclea Enginee ing, Bucha es , Romania
25cDepa men o Physics, Alexand u Ioan Cuza Uni e si y o Iasi, Iasi, Romania
25dNa ional Ins i u e o Resea ch and De elopmen o Iso opic and Molecula Technologies,
Physics Depa men , Cluj-Napoca, Romania
25eUni e si y Poli ehnica Bucha es , Bucha es , Romania
25 Wes Uni e si y in Timisoa a, Timisoa a, Romania
26aFacul y o Ma hema ics, Physics and In o ma ics, Comenius Uni e si y, B a isla a, Slo ak Republic
26bDepa men o Subnuclea Physics, Ins i u e o Expe imen al Physics o he Slo ak Academy o Sciences, Kosice, Slo ak Republic
27Physics Depa men , B ookha en Na ional Labo a o y, Up on, New Yo k, USA
28Depa amen o de Física (FCEN) and IFIBA, Uni e sidad de Buenos Ai es and CONICET, Buenos Ai es, A gen ina
29Cali o nia S a e Uni e si y, F esno, Cali o nia, USA
30Ca endish Labo a o y, Uni e si y o Camb idge, Camb idge, Uni ed Kingdom
31aDepa men o Physics, Uni e si y o Cape Town, Cape Town, Sou h A ica
31biThemba Labs, Wes e n Cape, Sou h A ica
31cDepa men o Mechanical Enginee ing Science, Uni e si y o Johannesbu g, Johannesbu g, Sou h A ica
31dNa ional Ins i u e o Physics, Uni e si y o he Philippines Diliman, Philippines
31eUni e si y o Sou h A ica, Depa men o Physics, P e o ia, Sou h A ica
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
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31 School o Physics, Uni e si y o he Wi wa e s and, Johannesbu g, Sou h A ica
32Depa men o Physics, Ca le on Uni e si y, O awa ON, Canada
33aFacul ´e des Sciences Ain Chock, R´eseau Uni e si ai e de Physique des Hau es Ene gies—Uni e si ´e Hassan II,
Casablanca, Mo occo
33bFacul ´e des Sciences, Uni e si ´e Ibn-To ail, K´eni a, Mo occo
33cFacul ´e des Sciences Semlalia, Uni e si ´e Cadi Ayyad, LPHEA-Ma akech, Mo occo
33dLPMR, Facul ´e des Sciences, Uni e si ´e Mohamed P emie , Oujda, Mo occo
33eFacul ´e des sciences, Uni e si ´e Mohammed V, Raba , Mo occo
33 Mohammed VI Poly echnic Uni e si y, Ben Gue i , Mo occo
34CERN, Gene a, Swi ze land
35En ico Fe mi Ins i u e, Uni e si y o Chicago, Chicago, Illinois, USA
36LPC, Uni e si ´e Cle mon Au e gne, CNRS/IN2P3, Cle mon -Fe and, F ance
37Ne is Labo a o y, Columbia Uni e si y, I ing on, New Yo k, USA
38Niels Boh Ins i u e, Uni e si y o Copenhagen, Copenhagen, Denma k
39aDipa imen o di Fisica, Uni e si `a della Calab ia, Rende, I aly
39bINFN G uppo Collega o di Cosenza, Labo a o i Nazionali di F asca i, I aly
40Physics Depa men , Sou he n Me hodis Uni e si y, Dallas, Texas, USA
41Physics Depa men , Uni e si y o Texas a Dallas, Richa dson, Texas, USA
42Na ional Cen e o Scien i ic Resea ch “Demok i os”, Agia Pa aske i, G eece
43aDepa men o Physics, S ockholm Uni e si y, Sweden
43bOska Klein Cen e, S ockholm, S ockholm, Sweden
44Deu sches Elek onen-Synch o on DESY, Hambu g and Zeu hen, Ge many
45Leh s uhl ü Expe imen elle Physik IV, Technische Uni e si ä Do mund, Do mund, Ge many
46Ins i u ü Ke n- und Teilchenphysik, Technische Uni e si ä D esden, D esden, Ge many
47Depa men o Physics, Duke Uni e si y, Du ham, No h Ca olina, USA
48SUPA—School o Physics and As onomy, Uni e si y o Edinbu gh, Edinbu gh, Uni ed Kingdom
49INFN e Labo a o i Nazionali di F asca i, F asca i, I aly
50Physikalisches Ins i u , Albe -Ludwigs-Uni e si ä F eibu g, F eibu g, Ge many
51II. Physikalisches Ins i u , Geo g-Augus -Uni e si ä Gö ingen, Gö ingen, Ge many
52D´epa emen de Physique Nucl´eai e e Co pusculai e, Uni e si ´e de Gen`e e, Gen`e e, Swi ze land
53aDipa imen o di Fisica, Uni e si `a di Geno a, Geno a, I aly
53bINFN Sezione di Geno a, Geno a, I aly
54II. Physikalisches Ins i u , Jus us-Liebig-Uni e si ä Giessen, Giessen, Ge many
55SUPA—School o Physics and As onomy, Uni e si y o Glasgow, Glasgow, Uni ed Kingdom
56LPSC, Uni e si ´e G enoble Alpes, CNRS/IN2P3, G enoble INP, G enoble, F ance
57Labo a o y o Pa icle Physics and Cosmology, Ha a d Uni e si y, Camb idge, Massachuse s, USA
58aDepa men o Mode n Physics and S a e Key Labo a o y o Pa icle De ec ion and Elec onics,
Uni e si y o Science and Technology o China, He ei, China
58bIns i u e o F on ie and In e disciplina y Science and Key Labo a o y o Pa icle Physics and Pa icle I adia ion (MOE),
Shandong Uni e si y, Qingdao, China
58cSchool o Physics and As onomy, Shanghai Jiao Tong Uni e si y, Key Labo a o y o Pa icle As ophysics and Cosmology (MOE),
SKLPPC, Shanghai, China
58dTsung-Dao Lee Ins i u e, Shanghai, China
59aKi chho -Ins i u ü Physik, Rup ech -Ka ls-Uni e si ä Heidelbe g, Heidelbe g, Ge many
59bPhysikalisches Ins i u , Rup ech -Ka ls-Uni e si ä Heidelbe g, Heidelbe g, Ge many
60aDepa men o Physics, Chinese Uni e si y o Hong Kong, Sha in, N.T., Hong Kong, China
60bDepa men o Physics, Uni e si y o Hong Kong, Hong Kong, China
60cDepa men o Physics and Ins i u e o Ad anced S udy, Hong Kong Uni e si y o Science and Technology, Clea Wa e Bay,
Kowloon, Hong Kong, China
61Depa men o Physics, Na ional Tsing Hua Uni e si y, Hsinchu, Taiwan
62IJCLab, Uni e si ´e Pa is-Saclay, CNRS/IN2P3, 91405, O say, F ance
63Depa men o Physics, Indiana Uni e si y, Blooming on, Indiana, USA
64aINFN G uppo Collega o di Udine, Sezione di T ies e, Udine, I aly
64bICTP, T ies e, I aly
64cDipa imen o Poli ecnico di Ingegne ia e A chi e u a, Uni e si `a di Udine, Udine, I aly
65aINFN Sezione di Lecce, Lecce, I aly
65bDipa imen o di Ma ema ica e Fisica, Uni e si `a del Salen o, Lecce, I aly
66aINFN Sezione di Milano, Milano, I aly
66bDipa imen o di Fisica, Uni e si `a di Milano, Milano, I aly
67aINFN Sezione di Napoli,Napoli, I aly
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
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67bDipa imen o di Fisica, Uni e si `a di Napoli, Napoli, I aly
68aINFN Sezione di Pa ia, Pa ia, I aly
68bDipa imen o di Fisica, Uni e si `a di Pa ia, Pa ia, I aly
69aINFN Sezione di Pisa, Pisa, I aly
69bDipa imen o di Fisica E. Fe mi, Uni e si `a di Pisa, Pisa, I aly
70aINFN Sezione di Roma, Roma, I aly
70bDipa imen o di Fisica, Sapienza Uni e si `a di Roma, Roma, I aly
71aINFN Sezione di Roma To Ve ga a, Roma, I aly
71bDipa imen o di Fisica, Uni e si `a di Roma To Ve ga a, Roma, I aly
72aINFN Sezione di Roma T e, Roma, I aly
72bDipa imen o di Ma ema ica e Fisica, Uni e si `a Roma T e, Roma, I aly
73aINFN-TIFPA, T en o, I aly
73bUni e si `a degli S udi di T en o, T en o, I aly
74Ins i u ü As o- und Teilchenphysik, Leopold-F anzens-Uni e si ä , Innsb uck, Aus ia
75Uni e si y o Iowa, Iowa Ci y, Iowa, USA
76Depa men o Physics and As onomy, Iowa S a e Uni e si y, Ames, Iowa, USA
77Join Ins i u e o Nuclea Resea ch, Dubna, Russia
78aDepa amen o de Engenha ia El´e ica, Uni e sidade Fede al de Juiz de Fo a (UFJF), Juiz de Fo a, B azil
78bUni e sidade Fede al do Rio De Janei o COPPE/EE/IF, Rio de Janei o, B azil
78cIns i u o de Física, Uni e sidade de São Paulo, São Paulo, B azil
79KEK, High Ene gy Accele a o Resea ch O ganiza ion, Tsukuba, Japan
80G adua e School o Science, Kobe Uni e si y, Kobe, Japan
81aAGH Uni e si y o Science and Technology, Facul y o Physics and Applied Compu e Science, K akow, Poland
81bMa ian Smoluchowski Ins i u e o Physics, Jagiellonian Uni e si y, K akow, Poland
82Ins i u e o Nuclea Physics Polish Academy o Sciences, K akow, Poland
83Facul y o Science, Kyo o Uni e si y, Kyo o, Japan
84Kyo o Uni e si y o Educa ion, Kyo o, Japan
85Resea ch Cen e o Ad anced Pa icle Physics and Depa men o Physics, Kyushu Uni e si y, Fukuoka, Japan
86Ins i u o de Física La Pla a, Uni e sidad Nacional de La Pla a and CONICET, La Pla a, A gen ina
87Physics Depa men , Lancas e Uni e si y, Lancas e , Uni ed Kingdom
88Oli e Lodge Labo a o y, Uni e si y o Li e pool, Li e pool, Uni ed Kingdom
89Depa men o Expe imen al Pa icle Physics, Jože S e an Ins i u e and Depa men o Physics,
Uni e si y o Ljubljana, Ljubljana, Slo enia
90School o Physics and As onomy, Queen Ma y Uni e si y o London, London, Uni ed Kingdom
91Depa men o Physics, Royal Holloway Uni e si y o London, Egham, Uni ed Kingdom
92Depa men o Physics and As onomy, Uni e si y College London, London, Uni ed Kingdom
93Louisiana Tech Uni e si y, Rus on, Louisiana, USA
94Fysiska ins i u ionen, Lunds uni e si e , Lund, Sweden
95Cen e de Calcul de l’Ins i u Na ional de Physique Nucl´eai e e de Physique des Pa icules (IN2P3), Villeu banne, F ance
96Depa amen o de Física Teo ica C-15 and CIAFF, Uni e sidad Au ónoma de Mad id, Mad id, Spain
97Ins i u ü Physik, Uni e si ä Mainz, Mainz, Ge many
98School o Physics and As onomy, Uni e si y o Manches e , Manches e , Uni ed Kingdom
99CPPM, Aix-Ma seille Uni e si ´e, CNRS/IN2P3, Ma seille, F ance
100Depa men o Physics, Uni e si y o Massachuse s, Amhe s , Massachuse s, USA
101Depa men o Physics, McGill Uni e si y, Mon eal QC, Canada
102School o Physics, Uni e si y o Melbou ne, Vic o ia, Aus alia
103Depa men o Physics, Uni e si y o Michigan, Ann A bo , Michigan, USA
104Depa men o Physics and As onomy, Michigan S a e Uni e si y, Eas Lansing, Michigan, USA
105B.I. S epano Ins i u e o Physics, Na ional Academy o Sciences o Bela us, Minsk, Bela us
106Resea ch Ins i u e o Nuclea P oblems o Byelo ussian S a e Uni e si y, Minsk, Bela us
107G oup o Pa icle Physics, Uni e si y o Mon eal, Mon eal QC, Canada
108P.N. Lebede Physical Ins i u e o he Russian Academy o Sciences, Moscow, Russia
109Na ional Resea ch Nuclea Uni e si y MEPhI, Moscow, Russia
110D.V. Skobel syn Ins i u e o Nuclea Physics, M.V. Lomonoso Moscow S a e Uni e si y, Moscow, Russia
111Fakul ä ü Physik, Ludwig-Maximilians-Uni e si ä München, München, Ge many
112Max-Planck-Ins i u ü Physik (We ne -Heisenbe g-Ins i u ), München, Ge many
113G adua e School o Science and Kobayashi-Maskawa Ins i u e, Nagoya Uni e si y, Nagoya, Japan
114Depa men o Physics and As onomy, Uni e si y o New Mexico, Albuque que, New Mexico, USA
115Ins i u e o Ma hema ics, As ophysics and Pa icle Physics, Radboud Uni e si y/Nikhe , Nijmegen, Ne he lands
116Nikhe Na ional Ins i u e o Suba omic Physics and Uni e si y o Ams e dam, Ams e dam, Ne he lands
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
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117Depa men o Physics, No he n Illinois Uni e si y, DeKalb, Illinois, USA
118aBudke Ins i u e o Nuclea Physics and NSU, SB RAS, No osibi sk, Russia
118bNo osibi sk S a e Uni e si y No osibi sk, No osibi sk, Russia
119Ins i u e o High Ene gy Physics o he Na ional Resea ch Cen e Ku cha o Ins i u e, P o ino, Russia
120Ins i u e o Theo e ical and Expe imen al Physics named by A.I. Alikhano o Na ional Resea ch Cen e “Ku cha o Ins i u e”,
Moscow, Russia
121Depa men o Physics, New Yo k Uni e si y, New Yo k, New Yo k, USA
122Ochanomizu Uni e si y, O suka, Bunkyo-ku, Tokyo, Japan
123Ohio S a e Uni e si y, Columbus, Ohio, USA
124Home L. Dodge Depa men o Physics and As onomy, Uni e si y o Oklahoma, No man, Oklahoma, USA
125Depa men o Physics, Oklahoma S a e Uni e si y, S illwa e , Oklahoma, USA
126Palacký Uni e si y, Join Labo a o y o Op ics, Olomouc, Czech Republic
127Ins i u e o Fundamen al Science, Uni e si y o O egon, Eugene, O egon, USA
128G adua e School o Science, Osaka Uni e si y, Osaka, Japan
129Depa men o Physics, Uni e si y o Oslo, Oslo, No way
130Depa men o Physics, Ox o d Uni e si y, Ox o d, Uni ed Kingdom
131LPNHE, So bonne Uni e si ´e, Uni e si ´e de Pa is, CNRS/IN2P3, Pa is, F ance
132Depa men o Physics, Uni e si y o Pennsyl ania, Philadelphia, Pennsyl ania, USA
133Kons an ino Nuclea Physics Ins i u e o Na ional Resea ch Cen e “Ku cha o Ins i u e”, PNPI, S . Pe e sbu g, Russia
134Depa men o Physics and As onomy, Uni e si y o Pi sbu gh, Pi sbu gh, Pennsyl ania, USA
135aLabo a ó io de Ins umen ação e Física Expe imen al de Pa ículas—LIP, Lisboa, Po ugal
135bDepa amen o de Física, Faculdade de Ciências, Uni e sidade de Lisboa, Lisboa, Po ugal
135cDepa amen o de Física, Uni e sidade de Coimb a, Coimb a, Po ugal
135dCen o de Física Nuclea da Uni e sidade de Lisboa, Lisboa, Po ugal
135eDepa amen o de Física, Uni e sidade do Minho, B aga, Po ugal
135 Depa amen o de Física Teó ica y del Cosmos, Uni e sidad de G anada, G anada (Spain), Spain
135gDep Física and CEFITEC o Faculdade de Ciências e Tecnologia, Uni e sidade No a de Lisboa, Capa ica, Po ugal
135hIns i u o Supe io T´ecnico, Uni e sidade de Lisboa, Lisboa, Po ugal
136Ins i u e o Physics o he Czech Academy o Sciences, P ague, Czech Republic
137Czech Technical Uni e si y in P ague, P ague, Czech Republic
138Cha les Uni e si y, Facul y o Ma hema ics and Physics, P ague, Czech Republic
139Pa icle Physics Depa men , Ru he o d Apple on Labo a o y, Didco , Uni ed Kingdom
140IRFU, CEA, Uni e si ´e Pa is-Saclay, Gi -su -Y e e, F ance
141San a C uz Ins i u e o Pa icle Physics, Uni e si y o Cali o nia San a C uz, San a C uz, Cali o nia, USA
142aDepa amen o de Física, Pon i icia Uni e sidad Ca ólica de Chile, San iago, Chile
142bUni e sidad And es Bello, Depa men o Physics, San iago, Chile
142cIns i u o de Al a In es igación, Uni e sidad de Ta apacá, A ica, Chile
142dDepa amen o de Física, Uni e sidad T´ecnica Fede ico San a Ma ía, Valpa aíso, Chile
143aUni e sidade Fede al de São João del Rei (UFSJ), São João del Rei, B azil
143bUni e sidad de la Se ena, La Se ena, Chile
144Depa men o Physics, Uni e si y o Washing on, Sea le, Washing on, USA
145Depa men o Physics and As onomy, Uni e si y o She ield, She ield, Uni ed Kingdom
146Depa men o Physics, Shinshu Uni e si y, Nagano, Japan
147Depa men Physik, Uni e si ä Siegen, Siegen, Ge many
148Depa men o Physics, Simon F ase Uni e si y, Bu naby BC, Canada
149SLAC Na ional Accele a o Labo a o y, S an o d, Cali o nia, USA
150Depa men o Physics, Royal Ins i u e o Technology, S ockholm, Sweden
151Depa men s o Physics and As onomy, S ony B ook Uni e si y, S ony B ook, New Yo k, USA
152Depa men o Physics and As onomy, Uni e si y o Sussex, B igh on, Uni ed Kingdom
153School o Physics, Uni e si y o Sydney, Sydney, Aus alia
154Ins i u e o Physics, Academia Sinica, Taipei, Taiwan
155aE. And onikash ili Ins i u e o Physics, I . Ja akhish ili Tbilisi S a e Uni e si y, Tbilisi, Geo gia
155bHigh Ene gy Physics Ins i u e, Tbilisi S a e Uni e si y, Tbilisi, Geo gia
156Depa men o Physics, Technion, Is ael Ins i u e o Technology, Hai a, Is ael
157Raymond and Be e ly Sackle School o Physics and As onomy, Tel A i Uni e si y, Tel A i , Is ael
158Depa men o Physics, A is o le Uni e si y o Thessaloniki, Thessaloniki, G eece
159In e na ional Cen e o Elemen a y Pa icle Physics and Depa men o Physics, Uni e si y o Tokyo, Tokyo, Japan
160Depa men o Physics, Tokyo Ins i u e o Technology, Tokyo, Japan
161Tomsk S a e Uni e si y, Tomsk, Russia
162Depa men o Physics, Uni e si y o To on o, To on o ON, Canada
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
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163aTRIUMF, Vancou e BC, Canada
163bDepa men o Physics and As onomy, Yo k Uni e si y, To on o ON, Canada
164Di ision o Physics and Tomonaga Cen e o he His o y o he Uni e se, Facul y o Pu e and Applied Sciences,
Uni e si y o Tsukuba, Tsukuba, Japan
165Depa men o Physics and As onomy, Tu s Uni e si y, Med o d, Massachuse s, USA
166Depa men o Physics and As onomy, Uni e si y o Cali o nia I ine, I ine, Cali o nia, USA
167Depa men o Physics and As onomy, Uni e si y o Uppsala, Uppsala, Sweden
168Depa men o Physics, Uni e si y o Illinois, U bana, Illinois, USA
169Ins i u o de Física Co puscula (IFIC), Cen o Mix o Uni e sidad de Valencia—CSIC, Valencia, Spain
170Depa men o Physics, Uni e si y o B i ish Columbia, Vancou e BC, Canada
171Depa men o Physics and As onomy, Uni e si y o Vic o ia, Vic o ia BC, Canada
172Fakul ä ü Physik und As onomie, Julius-Maximilians-Uni e si ä Wü zbu g, Wü zbu g, Ge many
173Depa men o Physics, Uni e si y o Wa wick, Co en y, Uni ed Kingdom
174Waseda Uni e si y, Tokyo, Japan
175Depa men o Pa icle Physics and As ophysics, Weizmann Ins i u e o Science, Reho o , Is ael
176Depa men o Physics, Uni e si y o Wisconsin, Madison, Wisconsin, USA
177Fakul ä ü Ma hema ik und Na u wissenscha en, Fachg uppe Physik, Be gische Uni e si ä Wuppe al, Wuppe al, Ge many
178Depa men o Physics, Yale Uni e si y, New Ha en, Connec icu , USA
aDeceased.
bAlso a Depa men o Physics, King’s College London, London, Uni ed Kingdom.
cAlso a Is anbul Uni e si y, Dep . o Physics, Is anbul, Tu key.
dAlso a Ins i u o de Fisica Teo ica, IFT-UAM/CSIC, Mad id, Spain.
eAlso a TRIUMF, Vancou e BC, Canada.
Also a Depa men o Physics, Uni e si y o F ibou g, F ibou g, Swi ze land.
gAlso a Depa men o Physics and As onomy, Uni e si y o Louis ille, Louis ille, Ken ucky, USA.
hAlso a Depa amen de Fisica de la Uni e si a Au onoma de Ba celona, Ba celona, Spain.
iAlso a Moscow Ins i u e o Physics and Technology S a e Uni e si y, Dolgop udny, Russia.
jAlso a Facul y o Physics, So ia Uni e si y, ’S . Klimen Oh idski’, So ia, Bulga ia.
kAlso a Depa men o Physics, Ben Gu ion Uni e si y o he Nege , Bee She a, Is ael.
lAlso a Uni e si a di Napoli Pa henope, Napoli, I aly.
mAlso a Ins i u e o Pa icle Physics (IPP), Vic o ia, Canada.
nAlso a B uno Kessle Founda ion, T en o, I aly.
oAlso a Depa men o Physics, S . Pe e sbu g S a e Poly echnical Uni e si y, S . Pe e sbu g, Russia.
pAlso a Bo ough o Manha an Communi y College, Ci y Uni e si y o New Yo k, New Yo k, New Yo k, USA.
qAlso a Depa men o Physics, Cali o nia S a e Uni e si y, F esno, USA.
Also a Depa men o Financial and Managemen Enginee ing, Uni e si y o he Aegean, Chios, G eece.
sAlso a Cen o S udi e Rice che En ico Fe mi, Rome, I aly.
Also a Depa men o Physics, Cali o nia S a e Uni e si y, Eas Bay, USA.
uAlso a Ins i ucio Ca alana de Rece ca i Es udis A anca s, ICREA, Ba celona, Spain.
Also a G adua e School o Science, Osaka Uni e si y, Osaka, Japan.
wAlso a Physikalisches Ins i u , Albe -Ludwigs-Uni e si ä F eibu g, F eibu g, Ge many.
xAlso a Uni e si y o Chinese Academy o Sciences (UCAS), Beijing, China.
yAlso a Ins i u e o Physics, Aze baijan Academy o Sciences, Baku, Aze baijan.
zAlso a Yedi epe Uni e si y, Physics Depa men , Is anbul, Tu key.
aaAlso a CERN, Gene a, Swi ze land.
bbAlso a Join Ins i u e o Nuclea Resea ch, Dubna, Russia.
ccAlso a Hellenic Open Uni e si y, Pa as, G eece.
ddAlso a Cen e o High Ene gy Physics, Peking Uni e si y, China.
eeAlso a The Ci y College o New Yo k, New Yo k, New Yo k, USA.
Also a Depa men o Physics, Cali o nia S a e Uni e si y, Sac amen o, USA.
ggAlso a D´epa emen de Physique Nucl´eai e e Co pusculai e, Uni e si ´e de Gen`e e, Gen`e e, Swi ze land.
hhAlso a Facul y o Physics, M.V. Lomonoso Moscow S a e Uni e si y, Moscow, Russia.
iiAlso a Ins i u ü Expe imen alphysik, Uni e si ä Hambu g, Hambu g, Ge many.
jjAlso a CPPM, Aix-Ma seille Uni e si ´e, CNRS/IN2P3, Ma seille, F ance.
kkAlso a Ins i u e o Pa icle and Nuclea Physics, Wigne Resea ch Cen e o Physics, Budapes , Hunga y.
llAlso a Gi esun Uni e si y, Facul y o Enginee ing, Gi esun, Tu key.
mmAlso a Depa men o Physics and As onomy, Michigan S a e Uni e si y, Eas Lansing, Michigan, USA.
nnAlso a Ins i u e o Theo e ical Physics, Ilia S a e Uni e si y, Tbilisi, Geo gia.
PHYSICAL REVIEW LETTERS 127, 271801 (2021)
271801-20