43rd Johns Hopkins Workshop

Session

JHW

3 Jun 2019, 13:20

Kavli IPMU, Kashiwa, Japan

3. Opening

03/06/2019, 13:20

4. Migdal Effect in Dark Matter Direct Detection Experiments and Its Applications

Masahiro Ibe

03/06/2019, 13:30

The elastic scattering of an atomic nucleus plays a central role in dark matter direct detection experiments. In those experiments, it is usually assumed that the atomic electrons around the nucleus of the target material immediately follow the motion of the recoil nucleus. In reality, however, it takes some time for the electrons to catch up, which results in ionization and excitation of the...

7. Baryon Asymmetry, Chiral Asymmetry, and the Magnetic Fields in the Universe

Kohei Kamada

03/06/2019, 14:15

I will talk about the nontrivial relationship among the baryon, the chiral asymmetry and the magnetic fields in the Universe. They are related through the chiral anomaly in the Standard Model, and hence the hypermagnetic fields can produce the baryon and the chiral asymmetry of the Universe and vice versa. This opens new possibilities of nontrivial phenomena in the early Universe. I will also...

5. Dark matter in split supersymmetry: thermal wino dark matter and beyond

Ayuki Kamada

03/06/2019, 15:30

(Mini) split supersymmetry explains the observed Higgs mass and evades stringent constraints, while keeps good features of TeV-scale supersymmetry other than the little hierarchy problem. A compelling dark matter candidate in split supersymmetric scenarios is thermal wino dark matter whose mass is around 3 TeV. Even if wino is lighter and its thermal relic is a sub-dominant component of dark...

8. Understanding halo substructure for indirect dark matter searches

Shin'ichiro Ando

04/06/2019, 10:30

It is believed that the dark matter structures were formed hierarchically through mergers and accretions of smaller structures. This means that larger dark matter halos host many smaller subhalos. Cosmological N-body simulations have been performed to probe properties of the subhalos. However, because of finite computational resources, it is not possible to resolve the subhalos all the way...

9. Constraining primordial black holes with microlensing

Masahiro Takada

04/06/2019, 11:30

10. Direct Detection of Dark Matter and XENONnT

Kai Martens

04/06/2019, 13:30

A brief review of the context of and general approaches to the direct
detection of dark matter will be given. We will then focus on the
XENONnT detector which is currently being built at LNGS in Italy and
Japanese know-how we contribute to it. Looking at the future we will close
by asking what will come after XENONnT.

12. Latest Results from the XENON1T Dark Matter Project

Shingo Kazama

04/06/2019, 14:15

The most recent results from XENON1T, the world largest direct dark matter search experiment, will be presented. XENON1T is a dual-phase xenon Time Projection Chamber (TPC) using 248 low radioactivity PMTs to detect scintillation signals in a 2-ton active liquid xenon target. Since November 2016, the XENON1T detector is continuously taking data, with a background rate of more than one order of...

13. Effects of an early matter dominated era on gravitational waves induced by scalar perturbations

Keisuke Inomata

04/06/2019, 14:30

We revisit the effects of an early matter dominated era on gravitational waves induced by scalar perturbations. We carefully take into account the evolution of the gravitational potential, source of the gravitational waves, around the transition from an early matter dominated era to the radiation dominated era. As a result, we find that the induced gravitational waves can be suppressed or...

14. Bouncing Universe from Nothing

Takahiro Terada

04/06/2019, 14:45

We find a class of solutions for a homogeneous and isotropic universe in which the initially expanding universe stops expanding, experiences contraction, and then expands again (the "bounce"), in the framework of Einstein gravity with a real scalar field without violating the null energy condition nor encountering any singularities. Two essential ingredients for the bouncing universe are the...

11. Accounting deep learning decision in Jet Classification

Mihoko M. Nojiri

04/06/2019, 15:30

15. The role of future lepton colliders for fermionic Z-portal dark matter

Taisuke Katayose

04/06/2019, 16:15

We discussed about the search for Z-portal dark matter using future lepton colliders
by analyzing mono-photon channel, and how they are effective compared to LEP experiment or
direct detection experiments.

16. Halometry from Astrometry

Neal Weiner

05/06/2019, 10:30

17. Neutrino Masses and Mixing: Theoretical Aspects

Serguey Petcov

05/06/2019, 11:30

he phenomenology of 3-neutrino mixing, the present status of our knowledge about the 3-neutrino mixing parameters, including the absolute neutrino mass scale, and of the Dirac and Majorana CP violation in the lepton sector, are summarised. The current theoretical ideas about the origins i) of neutrino masses and of the enormous disparity between their values and the values of the charged...

18. Perspective to search for dark components in the Universe with coherent photon collisions

Kensuke Homma

05/06/2019, 13:30

We will discuss possibilities to directly produce sub-eV to keV pseudo Nambu-Goldstone bosons with stimulated photon-photon collider experiments. Especially, we focus on whether we can reach gravitationally weak coupling domains in laboratory experiments so that the probed pNGBs can be natural candidates for dark components in the Universe.

19. An inflationary probe of cosmic Higgs switching

JiJi Fan

05/06/2019, 14:15

While the Higgs mass is fixed today, it is possible that the Higgs mass is dynamical and varied with time in the early Universe. In particular, there is an intriguing possibility that if the Higgs field couples to some oscillating scalar (e.g., a modulus) in the early Universe, the Higgs oscillated between symmetry preserving and broken phases. I will discuss one possible cosmological...

20. Anatomy of the tthh Physics

Ying-ying Li

05/06/2019, 15:30

I will talk about a comprehensive analysis on the tthh physics at colliders. This channel can be applied to detect Higgs self-couplings and hence probe for the nature of electroweak phase transition. It is also an important channel to search for heavy resonances in neutral naturalness models, e.g. Turtle Twin Higgs model, and constrain the scale of new physics from an EFT perspective.

21. Dark Matter Sommerfeld enhanced annihilation and bound-state decay at finite temperature

Tobias Binder

05/06/2019, 16:15

Long-range interactions can lead to the existence of meta-stable bound-state solutions in the spectrum of WIMPs. During the last decade, it has been shown that the formation and subsequent decay of these bound states into SM particles gives a significant effect in the relic density computation, typically allowing for heavier DM masses. In this talk, I present some recent progress made in how...

33. Higgs data does not rule out a sequential fourth generation fermion

Ipsita Saha

05/06/2019, 16:30

22. The effects of contamination on the estimation of dark matter annihilation profile of the Milky Way's dwarf spheroidal galaxies

Miho N. Ishigaki

06/06/2019, 10:30

I will present our collaborative effort to obtain a robust constraint on the expected gamma-ray flux from dark matter annihilation events in the Milky Way's dwarf spheroidal satellite galaxies. We have built a new statistical method to take into account the effects of contaminating foreground stars to the estimate of dark matter profile based on stellar kinematic measurements. The results of...

23. Gravitational particle production and dark matter

Kazunori Nakayama

06/06/2019, 11:30

In the purely gravitational dark matter scenario, the dark matter particle does not have any interaction except for gravitational one. We study the gravitational particle production of dark matter particle in such a minimal setup and show that correct amount of dark matter can be produced depending on the inflation model and the dark matter mass. In particular, we carefully evaluate the...

24. Weak Gravity Conjecture and Phenomenological Implications

Toshifumi Noumi

06/06/2019, 13:30

The Weak Gravity Conjecture, motivated by string theory and black hole thought experiments, states that gravity is the weakest force. In particular, it claims that there exist theoretical bounds on the charge-to-mass ratio and the axion decay constant in quantum gravity, which provides theoretical constraints on models of inflation and dark matter for example. In this talk, I will first review...

25. Unitarity Violation of Nonstandard Higgs Couplings

Spencer Chang

06/06/2019, 14:15

In this talk, I will discuss the link between nonstandard Higgs coupling and unitarity violation. This motivates a correlated effort at the LHC and future colliders between Higgs coupling measurements, searches for processes that grow at high energy, and new resonances. Calculations of the unitarity violating bounds help to identify the interesting collider channels and give upper bounds on...

26. Anthropic Bound on Dark Radiation

Fuminobu Takahashi

06/06/2019, 15:30

I will derive an anthropic bound on dark radiation based on the same argument adopted by S. Weinberg to derive the anthropic bound on the cosmological constant.

27. QCD Axion Stars in Cosmology and Astrophysics

Enrico D. Schiappacasse

06/06/2019, 15:45

In this talk I discuss QCD axion stars making emphasis on their stability and astrophysical properties. First, I cover the study of Bose-Einstein condensates of axion dark matter. I explain that these condensates form spatially localized clumps. I analyze both the ground state and higher eigenstates coming from finite angular momentum. I also discuss the possibility of these clumps undergo...

28. The Dark Matter-Phonon Coupling

Peter Cox

06/06/2019, 16:00

34. Gravitational waves induced by non-Gaussian scalar perturbations

Shi Pi

06/06/2019, 16:15

In this talk I will introduce our recent work on the secondary gravitational waves induced by non-Gaussian scalar perturbations with their connection to the primordial black holes which may be candidates for dark matter, and also discuss the possible detectability of such GWs on LISA-like detectors.

30. Dark Matter Targets with Exponentially Small Couplings

Josh Ruderman

07/06/2019, 10:30

31. Classical Firewalls in General Relativity

David Kaplan

07/06/2019, 11:30

We construct spherically symmetric solutions in GR with a thin shell of matter approaching Planckian densities. We show such constructions can replace the interior of charged (and potentially rotating) black holes by replacing the inner Cauchy horizon with a singular surface. We also show a shell can be placed a Planck distance away from the outer horizon of a Schwarzschild (or charged) black...

32. Closing

07/06/2019, 12:15

6. Baryon Asymmetry, Chiral Asymmetry, and the Magnetic Fields in the Universe

Kohei Kamada

I will talk about the nontrivial relationship among the baryon, the chiral asymmetry and the magnetic fields in the Universe. They are related through the chiral anomaly in the Standard Model, and hence the hypermagnetic fields can produce the baryon and the chiral asymmetry of the Universe and vice versa. This opens new possibilities of nontrivial phenomena in the early Universe. I will also...

2. By Serguey Petcov, " Neutrino Masses and Mixing: Theoretical Aspects''

The phenomenology of 3-neutrino mixing, the present status of our knowledge about the 3-neutrino mixing parameters, including the absolute neutrino mass scale, and of the Dirac and Majorana CP violation in the lepton sector, are summarised. The current theoretical ideas about the origins i) of neutrino masses and of the enormous disparity between their values and the values of the charged...

29. Hybrid Cosmological model with variable anisotropic parameter in extended theory of gravity

Bivudutta Mishra

In this paper, we construct cosmological models of the universe with an anisotropic variable parameter. The field equations for Bianchi type I space-time have been derived in $f(R,T)$ gravity for the functional relationship $f(R,T)=R+2f(T)$, where $R$ is the Ricci scalar and $T$ is the trace of the energy momentum tensor. Two different models are constructed with respect to the scale factors,...