Phenomenology 2017 Symposium

Session

Dark Sector & ALPs

8

8 May 2017, 16:30

G-27 (Benedum Hall)

404. Probing the chirality of dark matter at colliders with dark photon showering

Myeonghun Park (Institute for basic Science (KR))

08/05/2017, 16:30

parallel talk

As conventional dark matter scenarios have been probed extensively so far, the physics of a light dark matter charged under a new gauge group (dark gauge group) becomes one of new research avenues in many theoretical and experimental studies. We examine properties of a dark photon showering, the radiation process of light gauge bosons from energetic dark matter particles produced at the Large...

296. Hidden Valley searches at the LHCb

Dr Yue Zhao (University of Michigan), Dr Yue Zhao (University of Michigan), Yue Zhao, Yue Zhao (Rutgers), Yue Zhao (Stanford)

08/05/2017, 16:45

parallel talk

Dark shower is a generic feature of the Hidden Valley (HV) models. It has interesting implications on collider studies on Neutral Naturalness models. Bound states in the hidden sector are produced with a high multiplicity, low masses, and long lifetimes. A collider search of such signals requires good vertex resolution, low energy threshold, as well as a good particle id to veto the...

253. Revisiting Supernova 1987A Constraints on Dark Photons

Jae Hyeok Chang (YITP, Stony Brook)

08/05/2017, 17:00

parallel talk

We revisit constraints on dark photons with masses below ∼ 100 MeV from the observations of Supernova 1987A. If dark photons are produced in sufficient quantity, they reduce the amount of energy emitted in the form of neutrinos, in conflict with observations. For the first time, we include the effects of finite temperature and density on the kinetic-mixing parameter, ε, in this environment....

303. New constaints on SM-anomalous gauge symmetries

Jeff Dror (Cornell University)

08/05/2017, 17:15

parallel talk

In this talk I discuss unappreciated phenomenological consequences of classes of models with new light vector bosons coupled to anomalous currents of Standard Model fermions. Such couplings result in certain process rates growing quadratically with energy. Focusing on this class of constraints I derive new limits that are significantly stronger than in the previous literature for a wide...

286. Surveying the Landscape of Axially-Coupled Dark Forces

Siddharth Mishra Sharma (Princeton University)

08/05/2017, 17:30

parallel talk

I will describe the landscape of constraints on MeV-GeV scale, hidden U(1) forces with nonzero axial-vector couplings to Standard Model fermions. While the purely vector-coupled dark photon, which may arise from kinetic mixing, is a well-motivated scenario, several MeV-scale anomalies motivate a theory with axial couplings which can be UV-completed consistent with Standard Model gauge...

251. Astrophysics of Collapsing and Colliding Axion Stars

Joshua Eby (University of Cincinnati)

08/05/2017, 17:45

parallel talk

Axion stars are condensed states of large numbers of axion particles, bound by self-gravitation and quantum self-interactions. The mass of weakly bound axion stars is limited by gravitational stability, with condensates exceeding the maximum mass subject to collapse. During the collapse process, the axion density increases and higher-order self-interactions become increasingly relevant. By...

361. Emission of Photons and Relativistic Axions from Axion Stars

Abhishek Mohapatra (The Ohio State University)

08/05/2017, 18:00

parallel talk

The number of nonrelativistic axions can be changed by inelastic reactions that produce relativistic axions or photons. Any even number of nonrelativistic axions can scatter inelastically into two relativistic axions. Any odd number of axions can annihilate into two photons. This reaction produces a monochromatic radio-frequency signal at an odd-integer harmonic of the fundamental frequency...

310. Collider Probes of Axion-Like Particles

Andrea Thamm (Johannes-Gutenberg-Universitaet Mainz (DE))

08/05/2017, 18:15

parallel talk

We argue that the study of rare Higgs decays in the high-luminosity run at the LHC can probe axions and axion-like particles (ALPs) in a wide range of parameter space, which is otherwise inaccessible to experimental searches. If the ALP decays predominantly into photons, our strategy covers the current “gap” in the mass range between 1 MeV and 60 GeV down to photon- axion coupling as small as...

435. Self-interacting Vector Dark Matter in the Higgsed-Phase

Corey Kownacki (University of California, Riverside)

08/05/2017, 18:30

parallel talk

One simple proposal to explain observed anomalies in the small-scale structure of the universe is that dark matter self-interacts. In that spirit, we consider a model of non-abelian, non-confining, gauge boson dark matter that self-interacts through a light vector mediator. The dark sector consists of an SU(2) Yang-Mills theory that is twice-higgsed so that the physical low-energy spectrum...