The International Conference on Neutrinos and Dark Matter (NDM-2020)

Searches for Dark Matter with the IceCube neutrino telescope

Sebastian Baur (for the IceCube collaboration) 1

1 Université Libre de Bruxelles, Brussels, Belgium

The nature of dark matter is one of the long-standing open questions in modern cosmology. While many different experimental methods are being explored, a clear signature for particle dark matter is yet to be found. In indirect searches, the final state particles of decaying or self-annihilating dark matter could be observed with existing astro-particle experiments. Due to their small cross-section, neutrinos are able to escape from dense environments such as the Sun or the Earth which makes them unique messengers for dark matter searches. The IceCube neutrino telescope has a diverse program on dark matter searches exploring different source regions and possible mass-ranges. Furthermore, various models such as decaying, annihilating or secluded dark matter are studied.

Latest result from XMASS

Kazuyoshi Kobayashi 1, 2

1 Kamioka observatory, Institute of Cosmic Ray Research, the University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu, 506-1205, Japan
2 Kavli Institute for the Physics and Mathematics of the Universe (WPI), the University of Tokyo, Kashiwa, Chiba, 277-8582, Japan

XMASS is a multi-purpose experiment using a single-phase liquid-xenon scintillator detector located underground at Kamioka Observatory in Japan. The primary aim is to detect dark matter signal. We have taken data from November 2013 to February 2019, for more than five years. With this long-term data, we have conducted not only dark matter searches, but also various researches in particle and astroparticle physics. We report standard WIMPs, annual modulation, hidden photons and axio-like particles, and exotic neutrinos searches. No significant signals are observed in these searches.

Potential of SKA to Detect CDM ALPs with Radio Astronomy

Ahmed Ayad 1, Geoff Beck 1

1 School of Physics, University of the Witwatersrand, Private Bag 3, WITS-2050, Johannesburg, South Africa

Axions and Axion-like particles (ALPs) are light pseudo-scalar particles predicted in many theoretically well-motivated extensions to the standard model of particle physics (SM). The search for cold dark matter (CDM) ALPs has gained tremendous ground over the last few years. Essentially, ALPs are characterized by their coupling with two photons which allows axions to decay into pairs of photons. In this work, we explore the potential of the Square Kilometer Array (SKA) to detect CDM ALPs with radio astronomy in an attempt to detect an observational signature of ALPs conversion onto photons in astrophysical field.

SM-GR Reconciliation and Dark Sector

Durmuş Demir 1

1 Faculty of Engineering and Natural Sciences, Sabancı University, 34956 Tuzla, Istanbul, Turkey

Poincare breaking scale causes explicit gauge invariance breaking at the loop level in the standard model (SM) – a renormalizable QFT in flat spacetime. In this talk, we show that gauge invariance can be restored by extending the general covariance by a covariance relation for curvature such that this extended covariance carries effective QFTs into curved spacetime to lead up to QFT-GR reconciliation, with renormalized QFTs and emergent GR. This mechanism predicts the existence of new physics beyond the SM (BSM), and does not necessitate the BSM sector to have any non-gravitational coupling with the SM. The BSM sector can have a dark subsector comprising the dark matter, dark energy, and other possible SM-singlet fields.

Discrimination of Dark Matter Mass and Velocity Distribution by Directional Detection

Keiko I. Nagao 1

1 Okayama University of Science, Okayama 700-0005, Japan

Velocity distribution of dark matter is assumed to be isotropic in most cases, however, anisotropy is suggested in some simulations. Directional direct detection of dark matter is a hopeful way to discriminate the anisotropy of dark matter velocity distribution. We simulate the dark matter and target scattering in the directional direct detection, and investigate conditions required to discriminate the anisotropy. If dark matter mass is known, $O(10^3) - O(10^4)$ events are required for the discrimination if the dark matter mass is known by other experiments. We also study the case that the dark matter mass is not known, and in analysis using both the recoil energy and the scattering angle data, both the dark matter mass and the anisotropy can be restricted much better than the analysis only with either of them.

Challenges in string and supersymmetric cosmology

Ignatios Antoniadis 2, 1, Auttakit Chatrabhuti 3

1 Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland
2 Laboratoire de Physique Théorique et Hautes Energies - LPTHE, Sorbonne Université, CNRS, 4 Place Jussieu, 75005 Paris, France
3 Department of Physics, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330 , Thailand

We discuss the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Imposing an R-symmetry allows to satisfy easily the slow-roll conditions, avoiding the so-called $\eta$-problem, and leads to an interesting class of small field inflation models, characterised by an inflationary plateau around the maximum of the scalar potential near the origin, where R-symmetry is restored with the inflaton rolling down to a minimum describing the present phase of the Universe. Inflation can be driven by either an F- or a D-term, while the minimum has a positive tuneable vacuum energy. The models agree with cosmological observations and in the simplest case predict a rather small tensor-to-scalar ratio of primordial perturbations.

Observable Small-scale Effects of Thermal Inflation

Heeseung Zoe 1

1 School of Undergraduate Studies, College of Transdisciplinary Studies, DGIST, Daegu 42988, Republic of Korea

Thermal inflation, a brief low energy inflation after the primordial inflation, resolves the moduli problem in the context of supersymmetric cosmology. In the thermal inflation scenario, the primordial power spectrum is modestly redshifted on large scales, but suppressed by a factor of 1/50 on scales smaller than the horizon size at the beginning of thermal inflation. We compare the thermal inflation model with the warm dark matter and LCDM scenarios by studying CMB spectral distortions, halo abundances, and 21cm hydrogen lines.

Flavor physics and Jarlskog determinant

Jihn E. Kim 2, 1

1 Department of Physics and Astronomy, Seoul National University, 1 Gwanakro, Gwanak-Gu, Seoul 08826, Republic of Korea
2 Department of Physics, Kyung Hee University, 26 Gyngheedaero, Seoul 02447, Republic of Korea

The flavor problem is reviewed starting with the chiral symmetry, and the $A_4$ symmetry derivation and its realization in GUTs are presented.

Low scale seesaw models for low scale $U (1)_{L_\mu -L_\tau}$ symmetry

Takeshi Araki 3, Kento Asai 2, Joe Sato 1, Takashi Shimomura 4

1 Department of Physics, Saitama University, Shimo-Okubo 255, 338-y8570 Saitama Sakura-ku, Japan
2 Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 133-0033, Japan
3 Learning Support Center, Kogakuin University, 2665-1 Nakano, Hachioji, 192-0015 Tokyo, Japan
4 Faculty of Education, University of Miyazaki, 1-1 Gakuen-Kibanadai-Nishi, 889-2192 Miyazaki, Japan

We propose models for neutrino masses and mixing in the framework of low scale $U(1)_{L_\mu -L_\tau}$ gauge extension of the standard model. The models are designed to spontaneously break $U(1)_{L_\mu -L_\tau}$ so that the $U(1)_{L_\mu -L_\tau}$ gauge boson acquires an MeV scale mass, which is required to solve the long-standing problem of muon anomalous magnetic moment.

Predictions for the neutrino parameters in the minimal model extended by general lepton flavor-dependent $U(1)$ gauge symmetries

Kento Asai 1

1 Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 133-0033, Japan

Lepton flavor-dependent $U(1)$ gauge symmetries give strong constraints on the neutrino Dirac and Majorana mass matrices, and, in the cases of some kinds of $U(1)$s, the mass matrix for the light neutrinos have some zero elements. We study the minimal extensions of the Standard Model by a linear combination of $U(1)_{L_e -L_\mu}$, $U(1)_{L_\mu -L_\tau}$ and $U(1)_{B-L}$ gauge symmetries, which realizes the two-zero minor or texture structure in the mass matrix for the active neutrinos. Analyzing these structures of the neutrino mass matrix, we obtain the predictions for the neutrino parameters, such as the neutrino masses and Dirac CP phase. In addition, we also discuss the implication of our results for leptogenesis.

Exploring Neutrino-Dark Matter Interaction via Astrophysical Neutrinos at IceCube

Sujata Pandey 1, Siddhartha Karmakar 1, Subhendu Rakshit 1

1 Discipline of Physics, Indian Institute of Technology Indore,Khandwa Road, Simrol, Indore - 453552, India

Neutrinos can scatter off dark matter as they travel through the cosmos to reach the Earth. These interactions can alter neutrino spectrum at IceCube. We explore the possibility of changes in the neutrino spectrum as neutrino interact with the dark matter by considering various neutrino-dark matter interactions. In this context, interaction via light vector mediators are particularly interesting as they can lead to dip and cut-off like features in the neutrino spectrum at IceCube. We illustrate that various models of AGN, which predict more flux than the observed at IceCube, can be resolved through this mechanism. We have the scope to test such interactions in the upcoming detectors, e.g., IceCube- Gen2, GRAND, KM3NeT, etc.

A self-complementary neutrino mixing model

Xinyi Zhang 1, 2

1 INPAC, SKLPPC, and Department of Physics, Shanghai Jiao Tong University, 200240 Shanghai, China
2 School of Physics, Peking University, 100871 Beijing, China.

We construct the self-complementary (SC) neutrino mixing pattern from the SC relation plus $\delta_{CP}=-\frac{\pi}{2}$ and show that the indicated effective neutrino mass matrix has to be constructed perturbatively. We build an $S_4$ model for neutrino masses and mixings based on the SC neutrino mixing pattern. After performing a numerical study on the model’s parameter space, we find that the model is phenomenologically viable in the case of normal ordering, and it gives predictions for the not-yet observed quantities like the lightest neutrino mass $m_1 \in [0.003,0.010]$ eV and the Dirac CP violating phase $\delta_{CP} \in [256.72^\circ,283.33^\circ ]$, which can be tested in the future experiments.

Search for New Resonances

Aytul Adiguzel, on behalf of the ATLAS and CMS collaborations 1

1 Istanbul University, Istanbul, Turkey

Many theories beyond the Standard Model (BSM) predict new phenomena at the highest energies accessible by the LHC. Several searches for new resonances have been performed by the ATLAS and CMS experiments. This paper presents results using 13TeV $pp$ data collected during Run 2 by the ATLAS and CMS experiments.

Magnetic Monopole Dark Matter

Christopher B. Verhaaren 1

1 Department of Physics and Astronomy, University of California, Irvine, California 92697, USA

Magnetic monopoles are predicted by many quantum field theories. Non-minimal dark sectors may well includesuchparticles.Ishowhowdarkmagneticmonopolescanhavesmall,perturbative,couplingstothe visible sector, and how they might make up a portion of the observed dark matter. I clarify how such dark monopoles can be detected experimentally, including novel effects in Aharonov-Bohm phase detectors.

Testing SUSY GUTs at the Dark Matter and Collider Experiments

Cem Salih Ün 2, Zafer Altın 2, Ali Çiçi 2, Zerrin Kırca 2, Shabbar Raza 1, Qaisar Shafi 3, Tuğçe Tanımak 2

1 Department of Physics, Federal Urdu University of Arts, Science and Technology, Karachi 75300, Pakistan
2 Department of Physics, Bursa Uludağ University, TR16059 Bursa, Turkey
3 Bartol Research Intitute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA

We discuss low scale implications of a class of SUSY GUTs with non-universal SSB masses and confront them with the current experimental results from the direct detection of dark matter experiments, as well as the collider experiments of different center of mass energies. This class of SUSY GUTs are expected to be tested soon in direct detection dark matter experiments through the scatterings of Higgsino and Wino-like dark matters at nuclei. Besides, the stop and gluino will be able to be probed and tested up to about 5-6 TeV in the current and future collider experiments. These probe scales are expected to be further when high luminosities are achieved.

New Insights on Lepton Number and Dark Matter

Ernest Ma 1

1 hysics and Astronomy Department, University of California, Riverside, CA 92521, USA

Dark matter (DM) is usually assumed to be stabilized by a symmetry, which is mostly considered to be Z2. For example, in supersymmetry it is R parity, i.e. $(-1)^{3B+L+2j}$. . However, it may be $Z_n$ or $U(1)_D$, and derivable from generalized lepton number. In this context, neutrinos may be Majorana or Dirac, and owe their existence to dark matter, i.e. they are scotogenic.

Minimalistic Scotogenic Scalar Dark Matter

Valentina De Romeri 1

1 Institut de Física Corpuscular CSIC/Universitat de València, Parc Científic de Paterna C/ Catedrático Josè Beltrán, 2 E-46980 Paterna (Valencia) - Spain

n this talk, we reexamine the minimal Singlet + Triplet Scotogenic Model, where dark matter is the mediator of neutrino mass generation. We assume it to be a scalar WIMP, whose stability follows from the same $\mathbb{Z}_2$ symmetry that leads to the radiative origin of neutrino masses. We performed a full numerical analysis of the signatures expected at dark matter as well as collider experiments.

Two Component FIMP DM in a $U (1)_{B-L}$ Extension of the SM

Waleed Abdallah 3, 4, Sandhya Choubey 1, Sarif Khan 2

1 Department of Physics, School of Engineering Sciences, KTH Royal Institute of Technology, AlbaNova University Center, 106 91 Stockholm, Sweden
2 nstitut für Theoretische Physik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, Göttingen, D-37077 Germany
3 Harish-Chandra Research Institute, HBNI, Chhatnag Road, Jhunsi, Allahabad 211019, India
4 Department of Mathematics, Faculty of Science, Cairo University, Giza 12613, Egypt

In this work, we discuss two component fermionic FIMP dark matter (DM) in a popular $B -L$ extension of the standard model (SM) with inverse seesaw mechanism. Due to the introduced $\mathbb{Z}_2 $ discrete symmetry, a keV SM gauge singlet fermion is stable and can be a warm DM candidate. Also, this $\mathbb{Z}_2 $ symmetry helps the lightest right-handed neutrino, with mass of order GeV, to be a long-lived or stable particle by choosing a corresponding Yukawa coupling to be very small. Firstly, in the absence of a GeV DM component (i.e., without tuning its corresponding Yukawa coupling), we consider only a keV DM as a single component DM produced by the freeze-in mechanism. Secondly, we study a two component FIMP DM scenario and emphasize that the correct ballpark DM relic density bound can be achieved for a wide parameter space.

Exploring Neutrino Physics through Sneutrinos

Stefano Moretti 1, 3, Claire Shepherd-Themistocleous 1, 3, Harri Waltari 1, 3, 2

1 Particle physics department, STFC/Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, United Kingdom
2 Department of physics, University of Helsinki, P.O. box 64, 00014 Helsinki, Finland
3 Physics & Astronomy, University of Southampton, Southampton, SO17 1BJ, United Kingdom

Supersymmetry relates neutrinos with their superpartners, sneutrinos. Unlike neutrinos, sneutrinos may decay visibly in colliders. We discuss how we could get information from neutrino Yukawa couplings in the NMSSM extended with right- handed neutrinos, if the right-handed sneutrinos are within the reach of the colliders.

Dark-Matter Spontaneous Freeze Out

Hervé Partouche 1

1 CPHT, CNRS, Ecole polytechnique, IP Paris, F-91128 Palaiseau, France

We consider the possibility that thermalized dark-matter particles acquire their mass thanks to the spontaneous breaking of a symmetry below some critical temperature. We describe the regime where a freeze out mechanism takes place shortly after the onset of the phase transition, while the dark-matter mass has not yet reached its final constant value. For such a “spontaneous freeze out” to yield the correct relic density, the present-time cross section of annihilation of the dark matter into Standard-Model states has to be one or two orders of magnitude larger than in the case of a constant dark-matter mass.

Scotogenic Neutrino Masses and Dark Matter Stability from Residual Gauge Symmetry

Julio Leite 5, 3, Oleg Popov 4, 2, Rahul Srivastava 5, 1, José W. F. Valle 5

1 India Institute of Science Education and Research - Bhopal, Bhopal Bypass Road, Bhauri, 462066, Bhopal, India
2 Department of Physics, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
3 Centro de Ciˆencias Naturais e Humanas, Universidade Federal do ABC, 09210-580, Santo Andr´e-SP, Brasil
4 Institute of Convergence Fundamental Studies, Seoul National University of Science and Technology, Seoul 139-743, Republic of Korea
5 AHEP Group, Institut de Física Corpuscular – C.S.I.C./Universitat de Valéncia, Parc Científic de Paterna. C/ Catedrático José Beltrán, 2 E-46980 Paterna (Valencia) - SPAIN

In the context of the $SU(3)_c \bigotimes SU(3)_L \bigotimes U(1)_X \bigotimes U(1)_N (3-3-1-1)$ extension of the standard model, we show how the spontaneous breaking of the gauge symmetry gives rise to a residual symmetry which accounts for dark matter stability and small neutrino masses in a scotogenic fashion. As a special feature, the gauge structure implies that one of the light neutrinos is massless and, as a result, there is a lower bound for the $0\upsilon \beta\beta$ decay rate.

Prospect of the Electroweak Scale Right-Handed Neutrino Model in the Lifetime Frontier

Shreyashi Chakdar 1, P.Q Hung 2

1 Department of Physics, College of the Holy Cross, 1 College Street,Worcester, MA 01610, USA
2 Department of Physics, University of Virginia, Charlottesville, VA 22904-4714, USA

Motivated by the null results of the BSM searches in the post-Higgs era of the LHC, our current approach is to look for new physics shifting from theory driven search strategies to signature driven ones. One possible direction might come from investigating the long-lived particles (LLP’s) present in various theoretical scenarios through the newly formed “Lifetime frontier”. In this talk, I discuss a non-sterile right-handed neutrino model consisting of EW-scale Majorana masses, having signals with large displaced vertices arising in both the fermion and scalar sectors.The characteristic features in this model, the displaced vertices, i.e. several charged tracks originating from a position separated from the proton interaction point has to be greater than a mm and can be as long as order of centimeters. These events originating from the decays of the mirror fermions produce promising signatures at the LHC environment due to the low associated backgrounds. We discuss the experimental implications and possible search strategies in this framework and LHC’s potential to unravel these underlying events.

Implication of Electroweak Monopole

Y. M. Cho 2, 1

1 School of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
2 Center for Quantum Spacetime, Sogang University, Seoul 04107, Korea

The electroweak monopole in the standard model and it’s physical implications are discussed. It could generate the hitherto unknown magnetic current which has unlimited practical applications. Moreover, in cosmology it could generate the primordial magnetic black holes which might explain the dark matter, become the seed of the large scale structures of the universe, and be the source of the intergalactic magnetic field. Most importantly, if detected, it becomes the first magnetically charged and stable topological elementary particle in the history of physics.