Potential for deﬁnitive discovery of a 70 GeV dark matter WIMP with only second-order gauge couplings Bailey Tallman Alexandra Boone Adhithya Vijayakumar Fiona Lopez Samuel Apata Jehu Martinez and

2025-05-02 0 0 3.33MB 6 页 10玖币

侵权投诉

Potential for deﬁnitive discovery of a 70 GeV dark matter WIMP

with only second-order gauge couplings

Bailey Tallman, Alexandra Boone, Adhithya Vijayakumar, Fiona Lopez, Samuel Apata, Jehu Martinez, and

Roland Allen

Physics and Astronomy Department, Texas A&M University, College Station, Texas 77843, USA

Received: October 2022, Published: 2022

Abstract

As astronomical observations and their interpretation improve, the case for cold dark matter (CDM) be-

comes increasingly persuasive. A particularly appealing version of CDM is a weakly interacting massive

particle (WIMP) with a mass near the electroweak scale, which can naturally have the observed relic abun-

dance after annihilation in the early universe. But in order for a WIMP to be consistent with the cur-

rently stringent experimental constraints it must have relatively small cross-sections for indirect, direct,

and collider detection. Using our calculations and estimates of these cross-sections, we discuss the poten-

tial for discovery of a recently proposed dark matter WIMP which has a mass of about 70 GeV/c2and only

second-order couplings to W and Z bosons. There is evidence that indirect detection may already have

been achieved, since analyses of the gamma rays detected by Fermi-LAT and the antiprotons observed by

AMS-02 are consistent with 70 GeV dark matter having our calculated hσannvi ≈ 1.2 ×10−26 cm3/s. The

estimated sensitivities for LZ and XENONnT indicate that these experiments may achieve direct detec-

tion within the next few years, since we estimate the relevant cross-section to be slightly above 10−48 cm2.

Other experiments such as PandaX, SuperCDMS, and especially DARWIN should be able to conﬁrm on a

longer time scale. The high-luminosity LHC might achieve collider detection within about 15 years, since

we estimate a collider cross-section slightly below 1 femtobarn. Deﬁnitive conﬁrmation should come from

still more powerful planned collider experiments (such as a future circular collider) within 15-35 years.

Keywords: dark matter

There are many aspects of the dark matter problem [1, 2]

and a vast number of dark matter candidates [3, 4], with masses

and couplings spanning many orders of magnitude. The cold

dark matter (CDM) paradigm has, however, become increas-

ingly compelling during the past quarter century, because of

the growing sophistication of astronomical observations and

their interpretation [4, 5]. A particularly appealing version

of CDM continues to be weakly interacting massive particles

(WIMPs), since a weakly interacting particle with a mass near

the electroweak scale can naturally emerge from the early uni-

verse with about the observed relic abundance.

There are, however, stringent limits on the cross-sections

for direct, indirect, and collider detection. Figure 1 shows the

remarkable sensitivity achieved in direct detection experiments

during the past few decades [6], which demonstrates that a

viable dark matter candidate must have a very small cross-

section for scattering off an atomic nucleus.

As can be seen in Fig. 2, there are also strong bounds on

the cross-section for annihilation in the present universe, deter-

mined by observations of dwarf spheroidal galaxies [7].

Finally, the hopes for collider detection at the LHC have

not been realized, and strong limits have been placed on new

particles of any kind, including dark matter particles [8, 9].

Here we will focus on the potential for detection of a new

dark matter particle which is consistent with all experimen-

tal and observational limits, and which additionally appears

to be the only viable candidate with a well-deﬁned mass and

well-deﬁned couplings [10, 11, 12]. Since there are no free pa-

rameters, it is possible to determine the cross-sections for indi-

rect, direct, and collider detection, providing clean experimen-

tal tests of the theory.

FIGURE 1: Reach of previous direct detection experiments.

From Ref. [6], used with permission. The present dark mat-

ter candidate has couplings to only W and Z bosons, and

these are only second-order. It consequently has only a small

cross-section for scattering off atomic nuclei, estimated to be

slightly above 10−48cm2in the case of Xe [12], so it lies be-

low the sensitivities of earlier experiments. With a mass of

about 70 GeV/c2, it should barely be detectable by the LZ and

XENONnT experiments, both of which estimate a reach down

to about 1.4 ×10−48cm2for a dark matter particle with a mass

∼50 GeV/c2. The current and projected sensitivities of LZ and

XENONnT, shown in Figs. 3 - 6, demonstrate the grounds for

this prediction in more detail.

arXiv:2210.15019v1 [hep-ph] 24 Oct 2022

FIGURE 2: Upper bounds on hσannvifrom Fermi-LAT gamma-

ray observations of dwarf spheroidal galaxies near the Milky

Way. The solid and dashed curves are two limiting cases which

“should bracket somewhat the real energy correlation”. The

dashed gray line indicates the thermal relic cross section in-

ferred for generic WIMP models [13]. From Ref. [7], used with

permission.

This candidate is a WIMP with a mass of about 70 GeV/c2

and an annihilation cross section in the present universe given

by hσannvi ≈ 1.2 ×10−26 cm3/s, according to the calculations

described below, if it is assumed to constitute 100% of the dark

matter. It should be mentioned, however, that the present the-

ory also predicts supersymmetry (susy) at some energy scale,

and that the lightest superpartner [1, 14, 15, 16, 17, 18, 19, 20,

21, 22, 23] can be a subdominant component in a multicompo-

nent scenario.

The results above were obtained with MicrOMEGAs [24].

If we assume that the dark matter fraction ΩDM is 0.27, that the

present candidate constitutes all of the dark matter, and that the

reduced Hubble constant his 0.73 [25], we obtain ΩDM h2=

0.144. If it is instead assumed that a few percent of the dark

matter consists of other components, making ΩDM ≈0.26

for the present candidate, and that h=0.68 [26], one obtains

ΩDMh2≈0.120. (This value is equal to that obtained by Planck

for all dark matter in an analysis that conﬁrms the consistency

of standard ΛCDM cosmology [26].) Finally, as an extreme,

we can consider ΩDM =0.22 (for the present candidate) with

h=0.68, giving ΩDM h2=0.102.

Our calculations with MicrOMEGAs yield:

ΩDMh2=0.162, 0.147, 0.134, 0.121, 0.098 and

hσannvi=1.08, 1.19, 1.30, 1.43, 1.73 ×10−26 cm3/s, respectively,

for mh=69.5, 70.0, 70.5, 71.0, 72.0 GeV/c2.

We can conclude that mh=70 −72 GeV/c2and that

hσannvi=1.2 −1.7 ×10−26 cm3/s. It is then reasonable to

say that mhis about 70 GeV/c2and that correspondingly (with

some bias toward the measured value of h=0.73 over the the-

oretical value of h=0.68 in the context of the present universe)

hσannvi ≈ 1.2 ×10−26 cm3/s.

It can be seen that our calculated hσannviwith an approxi-

mately 70 GeV mass is well below the upper bounds of Fig. 2

for any of the above values of ΩDM h2.

FIGURE 3: Reach of LZ in July 2022. From Ref. [27], used with

permission.

FIGURE 4: Reach of LZ with 1000 days of data. From Ref. [28],

used with permission.

Our calculated mass and hσannviare also consistent with

analyses of the Galactic center gamma ray excess observed by

Fermi-LAT [30, 31, 32, 33, 34, 35] and the antiproton excess ob-

served by AMS-02 [36, 37, 38, 39, 40].

Ref. [33] concludes that “The center of the Milky Way is

predicted to be the brightest region of γ-rays generated by self-

annihilating dark matter particles. Excess emission about the

Galactic center above predictions made for standard astrophys-

ical processes has been observed in γ-ray data collected by the

Fermi Large Area Telescope. It is well described by the square

of a Navarro, Frenk, and White dark matter density distribu-

tion. Although other interpretations for the excess are plausi-

ble, the possibility that it arises from annihilating dark matter

is valid.... Its spectral characteristics favor a dark matter parti-

cle with a mass in the range approximately from 50 to 190 (10

to 90) GeV and annihilation cross section approximately from

1×10−26 to 4 ×10−25 (6 ×10−27 to 2 ×10−25) cm3/s for pseu-

doscalar (vector) interactions.”

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：

Potentialfordenitivediscoveryofa70GeVdarkmatterWIMPwithonlysecond-ordergaugecouplingsBaileyTallman,AlexandraBoone,AdhithyaVijayakumar,FionaLopez,SamuelApata,JehuMartinez,andRolandAllenPhysicsandAstronomyDepartment,TexasA&MUniversity,CollegeStation,Texas77843,USAReceived:October2022,Published:2022Ab...

展开>> 收起<<

Potential for deﬁnitive discovery of a 70 GeV dark matter WIMP with only second-order gauge couplings Bailey Tallman Alexandra Boone Adhithya Vijayakumar Fiona Lopez Samuel Apata Jehu Martinez and.pdf

共6页,预览2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！

Potential for deﬁnitive discovery of a 70 GeV dark matter WIMP with only second-order gauge couplings Bailey Tallman Alexandra Boone Adhithya Vijayakumar Fiona Lopez Samuel Apata Jehu Martinez and

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: