kozlov dpphysics 2019 4 · dark photons physics /theory, phenomenology, experiment/ g. kozlov jinr,...

Dark photons physics/theory, phenomenology, experiment/

G. KozlovJINR, Dubna

25.09.2019 G Kozlov J-PARC 10thY 2019 1

Dark Matter (what do we know)

DM established - Through gravitational interactions

• No exact particle nature of DM we have yet

Known more: DM originated as thermal relic from early Universe

If correct, - abundance of DM, if DM has non-gravitational interactions with SM Mass range for candidates

25.09.2019 G Kozlov J-PARC 10thY 2019

↓

𝑹𝒂𝒕𝒆𝑺𝑴 > 𝑹𝒂𝒕𝒆𝑯𝒖𝒃𝒃𝒍𝒆 𝒆𝒙𝒑.(𝒙𝒆𝑼)

~ 𝑀𝑒𝑉 − 10 𝑇𝑒𝑉𝑒𝑥𝑝𝑒𝑟𝑖𝑚𝑒𝑛𝑡𝑎𝑙 𝑝𝑟𝑜𝑏𝑒 𝑡𝑜 𝑟𝑢𝑙𝑒 𝑜𝑢𝑡 𝑡ℎ𝑒𝑟𝑚𝑎𝑙 𝐷𝑀

v DM stems from BGRD of Dark Photons

2


DM

Gravitational WIMP MiracleSUSY wimp ? ~ 100 GeV

Why?DM relic density consistent with weak interactions

Need low mass vector state – MEDIATOR to be consistent with DM Relic density

ΩJK~𝑚L∗N

𝑚OP Heavy “PHOTON”?

Dark Photon state ?

Ø Hidden sector scenario;DM does not interact directly to SM!

ü LDM requires new forces to correct relic abundance

DM search with WIMP (no results): 𝑆𝑈𝑆𝑌𝒏𝒐 𝒆𝒗𝒊𝒅𝒆𝒏𝒄𝒆 𝑨𝑻𝑳𝑨𝑺/𝑪𝑴𝑺

3

o Hidden sector scenario

- DM charged under new U’(1) gauge field mediator by U’(1) gauge boson.

- DP mixes with

o If DP is the mediator, the issues do arise:

- What is the symmetry to be responsible to its propagation

- Experimental search for the mediator – DP (observables, etc.)


𝑼(𝟏)𝒀 𝒃𝒚 𝝐 (free parameter, mixing angle)

4


vApproximate conformal breaking scenario

DM – SM mediator Dark Photon 𝑩𝝁 𝒙𝑖𝑛 𝑫𝒊𝒍𝒂𝒕𝒐𝒏 𝑐𝑜𝑛𝑑𝑒𝑛𝑠𝑎𝑡𝑒

𝑃j,𝑀jl 𝐷 𝐾j/Poincare/ /Scale/ /Conformal/

Generators of conformal group transformations

For any element g of Conformal group:

g 𝑒nopqp 𝑒n𝑩𝝁rp= 𝑒notpqp 𝑒n𝑩t𝝁rp 𝑒nuJ 𝑒nvpwKpw for 𝑥j , 𝑩𝝁 𝒙

Dark Photon field 𝑩𝝁 𝒙 ~𝑓yz𝜕j𝜎 𝑥

𝜎 𝑥 → 𝜎t 𝑥 = 𝜎 𝑥 + 𝜔𝑓, 𝑥j→ 𝑥jt = 𝑒�𝑥jNon-primary operator

GK, 2018

Ø Particle Physics / Cosmology:Ø All scales are subject of scale/conformal symmetry breaking

5


v Experiment. Fixed target idea

𝐷𝑃 → 𝑙 ̅𝑙, 𝐸Jq ≈ 𝐸��

𝜃Jq ≈𝑚Jq

𝐸��

�P≈ 0 𝑛𝑎𝑟𝑟𝑜𝑤

𝐷𝑃 → 𝑙 ̅𝑙, Θ�� ~𝑚Jq

𝐸��

ü Vertexing DP decays requires detector close to target

Signature: - Invariant mass - Momentum/mass resolution

requiredEM calorimeter ID 𝑙 𝑎𝑛𝑑 ̅𝑙

7

o Kinetic term: - mixing importance

• to estimate indirect/direct detection of DM - Indirect Annihilation to lepton-anti-leptons

- Direct DM scattering against nuclei


𝜎𝑣 ~𝛼JKP /𝑚�P . annihilation rate

𝑙�𝑙y : 𝜎𝑣 � ~𝝐𝟐𝛼 𝛼JK𝑚�P 𝑃 Δ

, Δ =𝑚Jq −𝑚�

𝑚�

𝜎𝑣 � ~𝝐𝟐𝛼 𝛼JK 𝜇��P

𝑚JqN

𝑍P

𝐴P, 𝜇�q =

𝑚� 𝑚�

𝑚� +𝑚�

𝝐𝟐

8


vHeavy photon searches v Fixed target

NA 64 @ SPS, PRD 97 (2018) 072002 PRL 123 (2019) 121801

HPS @ Jlab, PRD 98 (2018) 091101

- J-PARC, T2K ?- DUNE @ FNAL ?

Ø Low , 𝒍𝒐𝒘𝒎𝑫𝑷 → 𝒍𝒐𝒏𝒈𝒆𝒓 lifetime

o EM Telescope SHUKET

𝛼JK

Detect weak DM-induced electric field 𝐸JK~𝜖 𝑚 𝜓JK

𝑒y𝑍 → 𝑒y𝑍𝛾∗ → 𝑒y𝑍𝜒�̅� invisible10y¤ ≤ 𝜖LyL∗ ≤ 10yP

𝑚L∗ ≤ 1 𝐺𝑒𝑉

19 < 𝑚L∗ < 81 𝑀𝑒𝑉, 𝜀PLyL∗~ 6 ¬ 10y

(𝜇𝑒𝑉 𝑚𝑎𝑠𝑠 @𝑚𝑖𝑥𝑖𝑛𝑔 ~10yzP )

v Colliders- LHC, FASER 480 m downstream of ATLAS int. point 2020-21?

9

25.09.2019

LHC: DP experimental signature Overall signal strength in

Ø Origin: - SI breaking sector of CFT - Contribution from DP to BR

Salient feature: DP energy with cont. spectrum vs in SM Ø By measuring spectrum in one can discriminate the

presence of DP or not. Ø Strategy of the analysis: identify candidates by precise

reconstruction of the initial Higgs state. Ø The measured rate of such events has to be compared to that expected

from known sources ü DP signal (exp. signature): detected in missing and distribution

Once DP produced: spectrum is NO more -function peaked at but rather continuous with

gg → H σ( )→ γγ γγ∗( )

BR H → γγ∗( ) ≈ 1+aε2Ω( )BR SM H → γγ( ) , Ω~ 1−m 2 / mH2( )

3

γ∗ H → γγ

Eγ

H → γγ

E p

Eγ

δ 0.5mHE

γ= 0 , 0.5mH"# $%

G Kozlov J-PARC 10thY 2019 10

25.09.2019

High Energies: SM coupled to Scale Invariant (SI) sector

ü SI d.o.f. – scalar dilaton (D) appearance

Breaking of SI at triggers EW symmetry breaking at Ø Collider physics case (importance)

Why LHC14 and HL LHC instead lower energy machines?

Ø Higgs case D triggers the breaking of gauge invariance through D mass operator

ΛCFT = 4πfΛEW = 4πv , f ≥v = 246 GeV

f =vSU L 2( )×UY 1( )

G Kozlov J-PARC 10thY 2019

𝑚°~𝑓~𝑠±/P

At √𝑠 below Λ´µ¶, → 𝛽 𝑔n ≠ 0 𝐶𝑜𝑛𝑓𝑜𝑟𝑚𝑎𝑙 𝑏𝑟𝑒𝑎𝑘𝑖𝑛𝑔

𝐿¼½��= °¾ 𝜃jj(𝑆𝑀)

𝜃jj = 𝜃j

j 𝑆𝑀 ¼½�� + 𝜃jj 𝑆𝑀 �¿À�, 𝜃j

j 𝑆𝑀 �¿À�

= −𝛼Á8𝜋 𝑏ÃÄ𝐺jl� 𝐺jl� −

𝛼8𝜋 𝑏ÅKÄ𝐹jl𝐹jl −

11

Effect of DM sector on observable(s) Ø Mixing strength is bounded by

GK Nucl. Phys. B273 (2016)

ε ε <sd

v2Md−2( )2


s = 8−14 TeV, M = 800−1000 TeV, d = 4

12

Upper limit on mixing angle e NP signals with DP increase with For : Relevant energy scale Result: DP visible @ LHC for the UV scale up to TeV, d=4 If , the only decay is appropriate within SM ü LHC is a very good facility where the DM Physics can be tested well

s, d

H→ γγ ∗ L ~ OSM OIR ~ εψ γµψ H B µM −1

Q ~ mq, q : top,...

ε < 3⋅10−2 , q : top , d = 4; M >v

M <103


𝜀 → 0 𝐻 → 𝛾𝛾

13

Upper limit on DP mass

No final state interactions: (partial decay width)

For

Am γ∗ → νν( ) = 12 f νν gVν γβ + g Aν γβγ5( )νγβ∗

fν2 = 4 2Gm 2 , G ~ 10−5GeV −2

Γ γ∗ → νν( ) = 23α⋅ε2m

↓

2Ggν2m 2

4πα, gVν

2 = g Aν2 = g

ν2 =14


𝜀 < 3 ¬ 10yP → 𝑚 < 3.3 𝐺𝑒𝑉 GK (2016)

14

To predict , the more detailed calculations need E.g., EMNFF

DP mass: Combined calculations give

mν

γ∗ ν

Γ γ∗ → νν( )~ α2m 5G 2 ln Λν2

ml2−16

)

*++

,

-..

2


m≈ 𝑚j� PÉ±ÊË

∑Í:Î,p Ï¿ÐwÑ

ÒÍÑy

ËÓ

→ 𝑚 = 0.83 𝐺𝑒𝑉

Λl~𝑂 𝑚Õ , 𝜺 = 𝟕. 𝟔 ¬ 𝟏𝟎y𝟑 𝐺𝐾 (2016)

e, 𝜇 𝑙𝑜𝑜𝑝𝑠

15


v Field theory. SM𝐿ÜK= −

14𝐹jlP + Þ𝜓 𝑖𝐷j𝛾j − 𝑚� 𝜓 + 𝐷jΦ

P− 𝜆P Φ N

+ 𝜇ÃP Φ P

+ 2𝜂 yz𝑏 − 𝑏 𝜕 ¬ 𝐴 , 𝐷j= 𝜕j + 𝑖𝑒𝐴j

Ø Invariance under transformations:

𝐴j → 𝐴j + 𝜕jΛ, 𝑏 → 𝑏,

Φ → 𝑒nâãΦ, 𝜓 → 𝜓𝑒nâã, ∆PΛ 𝑥 = 0

16


𝐿ÜK = −zN𝐹jlP + Þ𝜓 𝑖𝐷j𝛾j − 𝑚� 𝜓 + 𝐷jΦ

P − 𝜆P Φ N + 𝜇ÃP Φ P +2𝜂 yz𝑏 − 𝑏 𝜕 ¬ 𝐴 , 𝐷j= 𝜕j + 𝑖𝑒𝐴j

𝐴j → 𝐴j + 𝛼𝜖 𝐵j trick

−zN𝐹jlP → −z

N𝐹jlP - z

P𝛼𝜖 𝐹jl𝐵jl −

zN𝛼𝜖 P𝐵jlP

𝐿ÜK�Jq�JK= −

14𝐹jlP −

12𝛼𝜖 𝐹jl𝐵jl −

14𝛼𝜖 P𝐵jlP + Þ𝜓 𝑖𝜕j𝛾j − 𝑚� 𝜓 − 𝑒𝐴j𝐽j

− 𝑔𝐵j𝐽j + 𝐷jΦP− 𝜆P Φ N + 𝜇ÃP Φ P + �̅� 𝑖𝜕j𝛾j − 𝑚O 𝜒

− 𝑔J 𝐵 ¬ 𝐽J − 𝑏 𝜕 ¬ 𝐴 − 𝑏 𝛼𝜖 𝜕 ¬ 𝐵 +12𝜂 𝑏

P

𝑔 = 𝑒𝛼𝜖, 𝐽j = Þ𝜓𝛾j𝜓, 𝐽jJ = �̅�𝛾j 𝜒

v Weak Dipole Dark Photon Model (WDDPM)

17


v WDDPM, symmetry breaking

Real fields 𝜙 + 𝑓 =12Φ +Φ∗ , 𝜑 =

−𝑖2Φ −Φ∗

Ω, 𝜑Ω = 0, 𝑓 = Ω, 𝜙 + 𝑓 Ω , Ω, Ω = 1

After symmetry breaking𝐿é= −

14𝐹jlP −

12𝛼𝜖 𝐹jl𝐵jl −

14𝛼𝜖 P 𝐵jlP − 𝑏 𝛼𝜖 𝜕𝐵 − 𝑏 𝜕𝐴 +

12𝜂𝑏P

+ �̅� 𝑖𝜕𝛾 − 𝑚O 𝜒 + Þ𝜓 𝑖𝜕𝛾 −𝑚� 𝜓 − 𝑒 𝐴𝐽 − 𝑔 𝐵𝐽 − 𝑔J 𝐵𝐽J

+𝒎𝟐

𝟐𝑩𝝁𝟐 +𝒎𝐵j𝜕j𝜑 −

12𝜇P𝜙P +

12

𝜕j𝜙P + 𝜕j𝜑

P

𝑚 = 𝑔𝑓 DP mas𝜇 = 2𝜆𝑓 𝑠𝑐𝑎𝑙𝑎𝑟 𝑑𝑖𝑙𝑎𝑡𝑜𝑛 𝑚𝑎𝑠𝑠 18


q Dark photon field itselfØBasic Eq.

𝑚P𝐵j +𝑚𝜕j𝜑 − 𝑔𝐽j − 𝑔J𝐽jJ + 𝛼𝜖 𝜕l𝐹lj+ 𝛼𝜖 P𝜕l𝐵lj + 𝛼𝜖 𝜕j𝑏 = 0

Ø Solution. DP field 𝑩𝝁 𝒙 = 𝒈𝑫𝒎𝟐 𝑱𝝁𝑫−

𝝏𝝁𝝋 𝒙𝒎

∆P∆P𝜑 𝑥 = �±�

∆P 𝜕 ¬ 𝐴 𝑥

𝑫𝑴 ← gôJôö → 𝑫𝑷 ← 𝜕ôφ → 𝑺𝑴↪ mediator

19

GK (2019)


q DM couplingsAnnihilation cross-section 𝑺𝑴𝝍 → 𝑫𝑴 𝝌

𝜎𝑣 ~𝑔P𝑔JP

4𝜋𝑇 P , 𝑔 = 𝑒𝛼𝜖, Relic abundance: ΥO~10yNâÑâ#

Ñ K$Í¶

If 𝑚O ~ 𝑂 𝑀𝑒𝑉𝑇%�½�À¿n� ��¼¼�½ ~ 𝑂 100 𝑀𝑒𝑉 < 𝑇� ~ 𝑂 170 𝑀𝑒𝑉

𝑔J~ 0.1 − 10if kinetic mixing for DP 𝜖 ~ 10y� − 10y¤

𝐿'( ⊃ 𝑒𝐽j𝐴j + 𝑔J 𝑄𝐽j + 𝐽jJ 𝐵j

𝑄~10y − 10yPØ DM – DP Mixing-coupling parameter

20


vLight DM Phenomenology

𝐿𝑖𝑔ℎ𝑡 𝐷𝑀 𝑚 > 2𝑚O

Invisible decays of DP: Γ 𝐵 → �̅�𝜒 = â#Ñ

zPÉ𝑚 1 +P�,

Ñ

�Ñ 1 −N�,

Ñ

�Ñ

Observable abundance density

𝑔JP ≈ 0.3𝜗 zÃÊ.

�

P �Ã.z /�0

N Ã.Ãz /�0�,

P, ϑ ≤ 1, 𝐷𝑀 𝑓𝑒𝑟𝑚𝑖𝑜𝑛𝑠

E. Izaguirre et al., PRD91 (2015)

𝑔J > 𝑔 = 𝑒 𝛼𝜖

21


§ DM search in missing energy events with NA 64 experiment

PRL 123 (2019) 121801D. Banerjee et al (NA64 Coll.)

Invisible decay of DP, to DM particles 𝑚JK ≤ 𝑚2L/2

22


Physical observables.

Both DM and DP are observables under stochastic forces ℎj 𝑥 ONLY

DP 𝐵j 𝑥 𝑓luctuations in medium: probability 𝑃 𝐵j ~𝑒𝑥𝑝 −𝐺 ℎj 𝛽

𝐺 ℎj = 𝑙𝑛:𝑑𝐵j𝑒y ∫ �o < o �=p o %p o

𝐹= = :𝑑ℎj𝐺 ℎj 𝑒y ∫ �o=p> o , 𝑛 = 1,2,… 𝜕jℎj 𝑥 = 𝛿 𝑥

Both DM and DP are not observables. 𝑏 𝑥 , 𝐵j 𝑦 ≠ 0, 𝑏 𝑥 , 𝜒 𝑦 ≠ 0

vDM & DP in medium.

• 𝑫𝑴 𝜒 𝑥 → B𝝌 𝒙; 𝒉𝝁 = 𝑒𝑥𝑝 𝑖𝑔 ∫𝑑N𝑦ℎj 𝑥 − 𝑦 𝐵j 𝑦 𝜒 𝑥

o 𝑫𝑷 𝐵j 𝑥 → E𝑩𝝁 𝒙; 𝒉𝝁 = ∫𝑑N𝑦 𝛿lj𝛿 𝑥 − 𝑦 − 𝜕jℎl 𝑥 − 𝑦 𝐵l 𝑦

23


v Dark photon explore: collider or fixed target?

𝑅µ¶/´ÀÏÏ =𝑁µ¶𝑁´ÀÏÏ

=𝐿µ¶𝐿´ÀÏÏ

𝐸µ¶𝐸´ÀÏÏ

P¿yP

𝑅µ¶/´ÀÏÏ =

10zzy¿ zÃÃ /�0 (�y��)<H´

10zNyI¿ zÃÃ /�0 (�y��) ÜqÜ ´Åé(<H´

,

10zyzz¿ z /�0 (�y��) J<��<H´

𝑛 = 0 𝑅µ¶/´ÀÏÏ ~10zzy 10z

𝑛 = 1 𝑅µ¶/´ÀÏÏ ~ 10¤

𝑛 = 2 𝑅µ¶/´ÀÏÏ ~10y − 10yz

𝑳𝒊𝒏𝒕/𝒎𝒆𝒅 = Ä𝒌,𝒍,𝒎,𝒏

𝒌�𝒍�𝒎L𝒏�𝟒𝑶𝑫𝑴

𝒌 𝑶𝑫𝑷𝒍 𝑶𝑺𝑴

𝒎

𝜦𝒏

𝜎~𝜖P𝜁P

𝐸P𝐸Λ

P¿Ø Production cross-section collider or fixed target?

24

Conclusion

1. Abelian conformal-gauge model for DP and interactions.

2. DP solution. DP massive.

3. DM - SM interactions through DP (the portal) as non-trivial combination of the derivatives of dilaton field.

4. Influence of Conformal Sector to SM sector.

5. DP production rate for collider and fixed target modes.


𝜺 = 7.6¬ 𝟏𝟎y𝟑, m = 0.83 GeV,

25

Спасибо за внимание!Thank you!

DM

DP is the conformal portal to DM


kozlov dpphysics 2019 4 · dark photons physics /theory, phenomenology, experiment/ g. kozlov jinr,...

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