Neutrino masses and self-interacting dark matter with mass mixing ZZ0gauge portal Leon M.G. de la Vegaand Eduardo Peinadoy Instituto de F sica Universidad Nacional Aut onoma de M exico A.P. 20-364 Ciudad de M exico 01000 M exico.

2025-05-02 0 0 1.22MB 11 页 10玖币

侵权投诉

Neutrino masses and self-interacting dark matter with mass mixing Z−Z0gauge portal

Leon M.G. de la Vega∗and Eduardo Peinado†

Instituto de F´ısica, Universidad Nacional Aut´onoma de M´exico, A.P. 20-364, Ciudad de M´exico 01000, M´exico.

Jos´e Wudka‡

Department of Physics and Astronomy, UC Riverside, Riverside, California 92521-0413, USA.

(Dated: October 27, 2022)

New light gauge bosons can aﬀect several low-energy experiments, such as atomic parity violation

or colliders. Here, we explore the possibility that a dark sector is charged under a new U(1)

gauge symmetry, and the portal to the Standard Model is through a Z−Z0mass mixing. In our

approach, breaking the new gauge symmetry is crucial to generate neutrino masses. We investigate

the parameter space to reproduce neutrino masses, the correct dark matter relic abundance, and to

produce the observed core-like DM distribution in galactic centers.

I. INTRODUCTION

The existence of dark matter and the non-zero neutrino masses are not explained within the Standard Model (SM)

of particle physics. Dark matter (DM) is a component of the universe that accounts for ∼27% of its total matter-

energy density [1]. No particle, fundamental or composite, in the SM can account for it. A possible way to incorporate

dark matter into the SM framework is to extend the gauge group GSM =SU(3)C×SU (2)L×U(1)Yto include a dark

gauge sector, under which the DM candidate is charged. One of the simplest ways to extend the SM is with an extra

abelian gauge symmetry U(1)D, which enlarges the gauge boson content of the SM. The dark sector of such a theory

may communicate with the SM particles via the kinetic mixing term of the abelian subgroups U(1)Yand U(1)D, the

mass mixing among the neutral gauge bosons, or the scalar sector. The connection through the kinetic mixing is a

popular and widely explored paradigm known as the dark photon [2–7], where the dark gauge boson acquires vector

couplings to the SM fermions. In the mass mixing case [8, 9], the dark gauge boson acquires both vector and axial

vector couplings to the SM fermions, leading to possible signatures in parity-violation experiments. This new gauge

boson can provide a viable communication channel between the DM and the SM, leading to the correct dark matter

relic density through the freeze-out while avoiding direct-detection constraints [10].

On the other hand, many neutrino mass generation mechanisms explain the lightness of Majorana neutrinos, compared

to the rest of SM fermions. Among them, a popular class of models is the so-called seesaw mechanism, where a large

mass scale suppresses the electroweak scale in the neutrino masses, giving rise to small neutrino masses. A popular

type of these models requires the introduction of right handed (RH) neutrinos, singlets of the SM. Diﬀerent mass

models may be obtained, depending on the mass terms present in the lagrangian after the breaking of GSM and

any other additional symmetries in the model, namely, the type-I seesaw [11–15], the linear seesaw [16–18] or the

inverse seesaw[19, 20]. Each of these models results in diﬀerent possible values for the heavy neutrino masses and

active-sterile neutrino mixings. In this work, we study the SM extended with an anomaly-free U(1)Dgauge symmetry.

The fermions, charged under the new gauge symmetry, will be identiﬁed with the right-handed neutrinos and the dark

matter candidate. An extra Higgs doublet, charged under the dark gauge symmetry, generates a mass mixing among

the dark gauge boson and the electroweak neutral gauge boson. The right-handed neutrinos’ and Higgs ﬁelds’ charges

shape the neutrino seesaw matrix [21]. Dark matter is connected to the SM matter ﬁelds through the neutral gauge

boson mass mixing, opening up viable thermal freeze-out channels and signatures in direct detection experiments.

II. THE MODEL

We consider the model for the mass mixing of a new gauge boson with the Zboson, described by Table I [22]. The

dark sector (stable after the SSB) consists of a vector-like pair of fermions χLand χR. Fermions charged under U(1)D

transform trivially under the SM gauge symmetry, guaranteeing the cancellation of all mixed SM-dark anomalies.

For each charged fermion under U(1)D, there is a fermion with an opposite charge, such that the pure U(1)Dand

∗leonm@estudiantes.ﬁsica.unam.mx

†epeinado@ﬁsica.unam.mx

‡jose.wudka@ucr.edu

arXiv:2210.14863v1 [hep-ph] 26 Oct 2022

L N N0F H1H2φ χLχc

SU(2)L2 1 1 1 2 2 1 1 1

U(1)Y−1/2 0 0 0 1/2 1/2 0 0 0

U(1)D0 1 −1 0 0 1 −1QD−QD

TABLE I: Matter content of the dark matter with mass mixed U(1)Dgauge boson. The model contains two dark

charges, we have chosen to absorb one of them into the deﬁnition of the dark gauge coupling, leaving the dark

matter charge QDfree.

the U(1)D-gravity anomalies vanish. The right-handed neutrinos N, N0, F , participate in the seesaw mechanism,

with their U(1)Dcharges shaping the seesaw mass matrix. The scalar sector will induce mass mixing among the

electroweak and dark neutral bosons, linking the SM fermions with the dark sector. The χﬁelds can act as a dark

matter candidate, interacting with SM ﬁelds through the mass-mixed dark gauge boson. In this way, we show that

the U(1)Dcan drive the phenomenology of neutrino and dark matter. The neutral gauge boson mixing will impact

the quark and lepton physics, such as parity violation in polarized electron-nucleon and electron-electron scattering.

A. Neutrino sector

The RH neutrinos are charged under the U(1)D. To generate the Yukawa Lagrangian, their charges must match

that of the H2Higgs doublet. To avoid extra Goldstone bosons, in the scalar sector we must have a term such as

H2H†

1φor H2H†

1φ2. From these two conditions, we conclude that the charge of φequals one of the RH neutrinos

charges. The two RH neutrinos N and N’ have a Dirac mass term. In contrast, there is no way to generate a Majorana

mass for any of those ﬁelds through the φﬁeld. The only way to do so is to include an extra fermion with no U(1)D

charge. In this way, the Lagrangian density of the neutrino sector is

Lν=Yν

1L˜

H1F+Yν

2L˜

H2N+M1NcN0+YNNcF φ +YN0N0CF φ∗+MFFCF+h.c. (1)

After spontaneous symmetry breaking (SSB) the resulting neutrino mass matrix in the (νL, N, N 0, F ) basis is

M=





0mD

20mD

(mD

2)T0M1YNvφ

0 (M1)T0YN0vφ

(mD

1)T(YN)Tvφ(YN0)TvφMF







,(2)

where mD

i=Yν

iviare the Dirac mass matrices. The light neutrino mass matrix is given by

mlight = (mD

1)TαmD

1+ (mD

2)TβmD

1+ (mD

1)TδmD

2+ (mD

2)TmD

2,(3)

where the α, β, δ,  matrices are deﬁned as

α=(MF+YN(MT

1)−1(YN0)Tv2

φ+YN0(M1)−1(YN)Tv2

φ)−1,

β=((YN)Tvφ)−1+ ((YN)Tvφ)−1M1(MT

1)−1[Id +MT

1(YNvφ)−1(YN0vφM−1

1(YNvφ)−1−MF)((YN0vφ)T)−1]−1,

δ=−(MT

1)−1(YN0vφ)T[MF+YN(MT

1)−1(YN0)Tv2

φ+YN0(M1)−1(YN)Tv2

φ]−1,

=−(YNvφ)−1[YN0vφ(MT

1)−1[Id +MT

1(YNvφ)−1(YN0vφM−1

1(YNvφ)−1−MF)((YN0vφ)T)−1]−1+MFβ],

(4)

where Id is the Identity Matrix. The minimal ﬁeld content leading to two massive light neutrinos is (Nr(N) =

2, Nr(N0) = 2, Nr(F) = 2). There are several familiar limits to this framework:

1. The type-I seesaw limit can be obtained when YN, Y N0→0 or YN, mD

2→0 or YN0, mD

2→0. The magnitude

of light neutrino masses is

mν∼v2

.(5)

2. When MF, mD

1→0, the light neutrino masses take the form of the inverse seesaw

mν∼(mD

2)2YN0

M1YN

.(6)

3. When MF, mD

2→0, the light neutrino masses take a inverse seesaw form

mν∼(m1

D)2M1

φYNYN0

.(7)

4. When YN, mD

1→0, the light neutrino masses take the form

mν∼(mD

2)2(YN0)2v2

1MF

.(8)

In this case, there is an extra suppression compared with the inverse seesaw from the light (heavy) scale vφ

(MF).

We will examine the viability of each limit, depending on the scale of vφindicated by DM phenomenology in section

(III E).

B. Dark Sector

We choose as dark matter candidate a Dirac fermion χ=χL+χRwith mass term

Lmass

χ=1

2Mχχχ. (9)

We choose QDso that Majorana mass terms are forbidden at any order in perturbation theory, with the scalar content

of Table I. The condition to keep the Dirac character of χis

QD6=m

2, m ∈.(10)

Since QD6= 0, χcouples to the dark gauge boson X; once the gauge symmetry is broken this induces a coupling

to both the physical Zboson and the dark photon Z0, see Eq. (18). For deﬁniteness we will choose QD= 1/3 that

satisﬁes Eq. (10). A similar dark matter model is described in [10].

C. Gauge sector

The U(1)Dcharges of the new ﬁelds, except for χ, are equal in magnitude. Therefore, we may redeﬁne the gauge

coupling and ﬁeld charges such that Q=±1 for these ﬁelds. With this in mind, the kinetic terms of the scalar ﬁelds

in the model deﬁned in Table I are

LSK =

i=1 (DµHi)†(DµHi)+(Dµφ)†(Dµφ),(11)

where the covariant derivatives for the SU(2)LHiggs doublets are

DµHi= (∂µ+ig

2~τ ·~

Wµ+ig0

2Bµ+igDQiXµ)Hi,(12)

with Q1= 0 and Q2= 1. The corresponding covariant derivative for the SU(2)Lscalar singlet is

Dµφ= (∂µ−igDXµ)φ . (13)

文档加载中……请稍候！
如果长时间未打开，您也可以点击刷新试试。

下载文档到电脑，查找使用更方便

10 玖币 0人已下载

立即下载

摘要：

Neutrinomassesandself-interactingdarkmatterwithmassmixingZZ0gaugeportalLeonM.G.delaVegaandEduardoPeinadoyInstitutodeFsica,UniversidadNacionalAutonomadeMexico,A.P.20-364,CiudaddeMexico01000,Mexico.JoseWudkazDepartmentofPhysicsandAstronomy,UCRiverside,Riverside,California92521-0413,USA.(Dated:...

展开>> 收起<<

Neutrino masses and self-interacting dark matter with mass mixing ZZ0gauge portal Leon M.G. de la Vegaand Eduardo Peinadoy Instituto de F sica Universidad Nacional Aut onoma de M exico A.P. 20-364 Ciudad de M exico 01000 M exico..pdf

共11页,预览3页

还剩页未读，继续阅读

声明：本站为文档C2C交易模式，即用户上传的文档直接被用户下载，本站只是中间服务平台，本站所有文档下载所得的收益归上传人(含作者)所有。玖贝云文库仅提供信息存储空间，仅对用户上传内容的表现方式做保护处理，对上载内容本身不做任何修改或编辑。若文档所含内容侵犯了您的版权或隐私，请立即通知玖贝云文库，我们立即给予删除！

Neutrino masses and self-interacting dark matter with mass mixing ZZ0gauge portal Leon M.G. de la Vegaand Eduardo Peinadoy Instituto de F sica Universidad Nacional Aut onoma de M exico A.P. 20-364 Ciudad de M exico 01000 M exico.

相关推荐

开通VIP享超值会员特权

作者详情

相关内容

热门标签

举报选择: