Minimal muon anomalous magnetic moment · 2018. 11. 16. · Broggio et al. 14 In a particular 2HDM!...
Transcript of Minimal muon anomalous magnetic moment · 2018. 11. 16. · Broggio et al. 14 In a particular 2HDM!...
Minimal muon anomalous magnetic moment
Based on JHEP 02 (2015) 099 in collaboration with M. Bordone
Carla Biggio Universita` di Genova
INVISIBLES15 Workshop Madrid, 22-26 June 2015
The (g-2)μ anomaly
3.1
Brookhaven 2006
Jegerlehner, Nyffeler 2009 (e+e- annih.)
�
The (g-2)μ anomaly
3 ways out: - theoretical: bad estimation of hadronic contribution ➛ disfavoured - experimental: ➛ wait for new experiment - new physics !!!
Brookhaven 2006
Jegerlehner, Nyffeler 2009 (e+e- annih.)
Passera et al. 2008-09Fermilab J-PARC
3.1 �
The (g-2)μ anomaly
3 ways out: - theoretical: bad estimation of hadronic contribution ➛ disfavoured - experimental: ➛ wait for new experiment - new physics !!!
adopt this optimistic option :)
Brookhaven 2006
Jegerlehner, Nyffeler 2009 (e+e- annih.)
Passera et al. 2008-09Fermilab J-PARC
3.1 �
Explaining Δaμ with a single new particleAssumptions: 1. add only 1 particle to the SM
2. consider only fermions and scalars
Explaining Δaμ with a single new particle
In the SM (g-2) is a D=6 operator
At 1 loop, for example:
Assumptions: 1. add only 1 particle to the SM 2. consider only fermions and scalars
Explaining Δaμ with a single new particle
In the SM (g-2) is a D=6 operator
At 1 loop, for example:
Assumptions: 1. add only 1 particle to the SM 2. consider only fermions and scalars
Requirements: 1. Lorentz invariance 2. Gauge invariance 3. Renormalizability
New fermions
NR (1, 1, 0)�R (1, 3, 1)E4 (1, 1,�1)L4 (1, 2,�1/2)T (1, 3,�1)D (1, 2,�3/2)
typeI seesawtypeIII seesaw
4th generation.}
All vector-like: masses indep. of EWSB, no anomalies
New fermions
NR (1, 1, 0)�R (1, 3, 1)E4 (1, 1,�1)L4 (1, 2,�1/2)T (1, 3,�1)D (1, 2,�3/2)
typeI seesawtypeIII seesaw
4th generation.}
✘
✘CB 09
All vector-like: masses indep. of EWSB, no anomalies
New fermions
NR (1, 1, 0)�R (1, 3, 1)E4 (1, 1,�1)L4 (1, 2,�1/2)T (1, 3,�1)D (1, 2,�3/2)
typeI seesawtypeIII seesaw
4th generation.}
✘
✘✘
✘
CB 09, Freitas et al. 14
✘
All vector-like: masses indep. of EWSB, no anomalies
Freitas et al. 14
Freitas et al. 14
Only L4 gives a positive contribution but too small (EWPT)
✳
✳
New fermions
NR (1, 1, 0)�R (1, 3, 1)E4 (1, 1,�1)L4 (1, 2,�1/2)T (1, 3,�1)D (1, 2,�3/2)
typeI seesawtypeIII seesaw
4th generation.}
✘
✘✘
✘
CB 09, Freitas et al. 14
✘
All vector-like: masses indep. of EWSB, no anomalies
Freitas et al. 14
Only L4 gives a positive contribution but too small (EWPT)
✳
✳
Freitas et al. 14
?
The contribution of D ∼ (1,2,-3/2)
Q=1
Q=2
SM
CB, Bordone 14
The contribution of D ∼ (1,2,-3/2)
Q=1
Q=2
The new contribution is negative it cannot explain the discrepancy
SM
CB, Bordone 14
New fermions
NR (1, 1, 0)�R (1, 3, 1)E4 (1, 1,�1)L4 (1, 2,�1/2)T (1, 3,�1)D (1, 2,�3/2)
typeI seesawtypeIII seesaw
4th generation.}
✘
✘✘
✘
CB 09, Freitas et al. 14
✘
All vector-like: masses indep. of EWSB, no anomalies
Freitas et al. 14 CB, Bordone 14
Freitas et al. 14
✘ CB, Bordone 14
It’s not possible to explain the discrepancy adding to the SM a single fermion
New scalars
type II seesaw
S1 (1, 1, 1)S2 (1, 1, 2)H2 (1, 2, 1/2)� (1, 3, 1)
T 1/3c (3, 3,�1/3)
S1/3c (3, 1,�1/3)
S4/3c (3, 1,�4/3)
D7/6c (3, 2, 7/6)
D1/6c (3, 2, 1/6)
II Higgs doublet
leptoquarks
New scalars
type II seesaw
S1 (1, 1, 1)S2 (1, 1, 2)H2 (1, 2, 1/2)� (1, 3, 1)
T 1/3c (3, 3,�1/3)
S1/3c (3, 1,�1/3)
S4/3c (3, 1,�4/3)
D7/6c (3, 2, 7/6)
D1/6c (3, 2, 1/6)
II Higgs doublet
✘
✘
✘
Coaraza Perez et al. 95
Gunion et al. 89
(from S1 and S2 results)
leptoquarks
New scalars
type II seesaw
S1 (1, 1, 1)S2 (1, 1, 2)H2 (1, 2, 1/2)� (1, 3, 1)
T 1/3c (3, 3,�1/3)
S1/3c (3, 1,�1/3)
S4/3c (3, 1,�4/3)
D7/6c (3, 2, 7/6)
D1/6c (3, 2, 1/6)
II Higgs doublet
✘
✘
✘
✘
✘
✘
✔
✔
Chakraverty et al. 01 Cheung 01
Coaraza Perez et al. 95
Gunion et al. 89
(from S1 and S2 results)
leptoquarks
New scalars
type II seesaw
S1 (1, 1, 1)S2 (1, 1, 2)H2 (1, 2, 1/2)� (1, 3, 1)
T 1/3c (3, 3,�1/3)
S1/3c (3, 1,�1/3)
S4/3c (3, 1,�4/3)
D7/6c (3, 2, 7/6)
D1/6c (3, 2, 1/6)
II Higgs doublet
✘
✘
✘
✘
✘
✘
✔
✔
Chakraverty et al. 01 Cheung 01
Coaraza Perez et al. 95
Gunion et al. 89
(from S1 and S2 results)
leptoquarks
Only these because they have both L and R couplings ➢ enhancement with top (charm) mass
New scalars
type II seesaw
S1 (1, 1, 1)S2 (1, 1, 2)H2 (1, 2, 1/2)� (1, 3, 1)
T 1/3c (3, 3,�1/3)
S1/3c (3, 1,�1/3)
S4/3c (3, 1,�4/3)
D7/6c (3, 2, 7/6)
D1/6c (3, 2, 1/6)
II Higgs doublet
✘
✘
✘
✘
✘
✘
✔
✔
✔
Chakraverty et al. 01 Cheung 01
Coaraza Perez et al. 95
Gunion et al. 89
Broggio et al. 14
In a particular 2HDM if lighter than 200 GeV
(from S1 and S2 results)
leptoquarks
Only these because they have both L and R couplings ➢ enhancement with top (charm) mass
The bR of the Higgsinoless MSSM∼
Riva, CB, Pomarol 12
It’s a SUSY model without R-parity (with U(1)R) where there are NO chiral Higgs superfields: the Higgs is identified with a sneutrino
The bR of the Higgsinoless MSSM∼
Riva, CB, Pomarol 12
It’s a SUSY model without R-parity (with U(1)R) where there are NO chiral Higgs superfields: the Higgs is identified with a sneutrino
W � YdL�QD L� = (�̃� � H, ��)
The bR of the Higgsinoless MSSM∼
Riva, CB, Pomarol 12
It’s a SUSY model without R-parity (with U(1)R) where there are NO chiral Higgs superfields: the Higgs is identified with a sneutrino
W � YdL�QD L� = (�̃� � H, ��)
Ydh0bLbR + Ydl�tLb̃R + ...
The bR of the Higgsinoless MSSM∼
Riva, CB, Pomarol 12
It’s a SUSY model without R-parity (with U(1)R) where there are NO chiral Higgs superfields: the Higgs is identified with a sneutrino
W � YdL�QD L� = (�̃� � H, ��)
Ydh0bLbR + Ydl�tLb̃R + ...
l� � µIn our case , the bR coupling is fixed to be Yb
aLQµ � v2Y 2
b
M2LQ
we have a prediction for MLQ
Mb̃R� 500GeV
The bR of the Higgsinoless MSSM∼
CB Bordone 14
In the Higgsinoless MSSM we can explain the (g-2) anomaly with a sbottom of mass Mb̃R
� 500 GeV
The bR of the Higgsinoless MSSM∼
CB Bordone 14
In the Higgsinoless MSSM we can explain the (g-2) anomaly with a sbottom of mass
Which are the current bounds?
Mb̃R� 500 GeV
The bR of the Higgsinoless MSSM∼
CB Bordone 14
Bounds from decay into bv: Br=1 M>620 GeV Br=0.6 M>520 GeV
ATLAS 13
In the Higgsinoless MSSM we can explain the (g-2) anomaly with a sbottom of mass
Which are the current bounds?
Mb̃R� 500 GeV
The bR of the Higgsinoless MSSM∼
CB Bordone 14
Bounds from decay into bv: Br=1 M>620 GeV Br=0.6 M>520 GeV
ATLAS 13
In the Higgsinoless MSSM we can explain the (g-2) anomaly with a sbottom of mass
Which are the current bounds?
In our model: b̃R � bL�L
tLlL(bRG̃)
same BR
Mb̃R� 500 GeV
This possibility is viable, to confirm/exclude it look for final states with top and charged leptons!!!
ConclusionsWe have considered single particle extensions of the SM (scalar & fermion)
A single new fermion cannot explain the (g-2)μ anomaly
Only 3 scalars -2 leptoquarks and a second Higgs doublet- can do it
The bR of the Higgsinoless MSSM could solve the (g-2)μ puzzle and we have a prediction for its mass:
Most of these solutions are going to be tested @ LHC13
Wait for new LHC run and new (g-2)μ experiment!
Mb̃R� 500 GeV
Muchas gracias
!
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