The 14th International Workshop Dark Side Of the Universe

25 juin 2018, 08:00 → 29 juin 2018, 23:50 Europe/Paris

Auditorium (Annecy-le-Vieux, France)

The 14th international workshop on the "Dark Side of the Universe 2018" will be held at LAPTh, Annecy, France. The Dark Side of the Universe (DSU) workshops bring together a wide range of theorists and experimentalists to discuss ideas on models of the dark side, and relate them to current and future experiments.

Topics covered include dark matter, dark energy, cosmic rays, cosmology,  gravitational waves, and physics beyond the standard model

 

lundi 25 juin

08:30 → 09:00 Registration

09:00 → 09:20 Introduction

Président de session: Carlos Munoz (IFT, Madrid)

DSU 2018_Annecy.ppt

09:20 → 10:40 Dark matter and direct detection

Président de session: S. Khalil

09:20 Where are the WIMPs?

Orateur: Felix Kahlhoefer

Kahlhoefer_dsu2018.pdf

10:00 Searching for low-mass dark matter with cryogenic detectors

Orateur: Julien Billard

DSU_Billard.pdf

10:40 → 11:10 Coffee break

11:10 → 13:00 Dark matter direct detection phenomenology

Président de session: Paolo Gondolo

11:10 Effective theories for direct detection

Orateur: Bradley Kavanagh

KAVANAGH-DSU2018-v2.pdf

11:50 Impact of simulation results for DM searches

Orateur: Nassim Bozorgnia

Bozorgnia-DSU18.pdf

12:30 Self-consistent description of the dark matter velocity distribution: from galactic dynamics to phenomenology

In the context of dark matter (DM) searches, it is crucial to quantify and reduce theoretical uncertainties affecting predictions that depend on the DM velocity distribution, including event rates in direct searches, velocity-dependent annihilation rates, and microlensing event rates for DM compact objects. The well-known Eddington inversion formalism for the self-consistent reconstruction of the DM velocity distribution from a Galactic mass model allows one to go beyond the simplistic Maxwellian approximation or direct fits to cosmological simulations. However, this method and its anisotropic extensions can be ill-defined depending on the DM and baryonic content of the galaxy of interest.

In this presentation, I will first discuss the validity range of the Eddington inversion methods from a theoretical perspective, as well as issues such as the impact of the finite boundary of a galactic system on observables relevant to DM searches. Then, even in their theoretical validity range, these methods must be tested against hydrodynamical cosmological simulations to assess their relevance for complex gravitational systems such as Milky-Way-like galaxies. I will therefore discuss the predictivity of these methods based on zoom simulations. Finally, as an application, I will present novel constraints on p-wave suppressed DM annihilation from positron data, and their associated theoretical uncertainties.

Orateur: Dr Thomas Lacroix (Laboratoire Univers & Particules de Montpellier)

DSU_2018_TL.pdf

13:00 → 14:30 Lunch

14:30 → 15:20 Dark matter candidates I

Président de session: Csaba Balazs (Monash University)

14:30 Susy DM

Orateur: Keith Olive

Olive-DSU18.pdf

15:00 Thermalisation and DM production

Orateur: Yann Mambrini

Mambrini_DSU18.pdf

15:20 → 16:00 Parallel I: Direct detection

Président de session: Doojin Kim

20180625DSU_DANAE_SHI.pdf

15:20 Directional Search for Dark Matter Using Nuclear Emulsion

A variety of experiments have been developed over the past decades, aiming at the detection of Weakly Interactive Massive Particles (WIMPs) via their scattering in an instrumented medium. The sensitivity of these experiments has improved with a tremendous speed, thanks to a constant development of detectors and analysis methods. Detectors capable of reconstructing the direction of the nuclear recoil induced by the WIMP scattering are opening a new frontier to possibly extend Dark Matter searches beyond the neutrino background. Exploiting directionality would also give a proof of the galactic origin of dark matter making it possible to have a clear and unambiguous signal to background separation. The NEWSdm experiment, based on nuclear emulsions, is a new experiment proposal intended to measure the direction of WIMP-induced nuclear recoils with a solid-state detector, thus with a high sensitivity. We discuss the discovery potential of a directional experiment based on the use of a solid target made of newly developed nuclear emulsions and novel read-out systems achieving nanometric resolution. We also report results of a technical test conducted in Gran Sasso.

Orateur: Ali Murat Guler

DSU2018_mguler_NEWSdm.ppt

15:40 Latest results from the LUX Dark Matter Experiment

LUX (Large Underground Xenon) was a 250 kg dual-phase (liquid/gas) xenon TPC with an active mass of 250 kg that operated at the Sanford Underground Research Facility (SURF) in the US, from 2013 until 2016. Its main objective was to look for evidence of galactic dark matter in the form of Weakly Interacting Massive Particles (WIMPs). During the full 427 live-days run, it excluded WIMP-nucleon spin-independent cross sections above 1.1×10$^{-46}$ cm$^2$ (90% confidence level) at a WIMP mass of 50 GeV/c$^2$. Due to its low radioactive and large sensitivity, LUX is able to look for other dark matter particle candidates and rare event signals. In this presentation, we will report the most recent results from several new data analyses such as: an effective field theory approach to explore a more general set of possible nuclear responses from WIMP-nucleon scattering, mirror dark matter searches with the electron recoil data, and searches for annual and diurnal rate modulations in the data. We will also present the most recent calibrations studies, such as i) pulse shape discrimination, ii) $^{14}$C beta calibrations, iii) nuclear recoil calibration using a pulsed D–D neutron generator. These calibrations are essential to the development of the next generation of dark matter detectors.

Orateur: Cláudio Silva (LIP Coimbra)

20180625_ClaudioSilva_DSU.pdf

15:20 → 16:00 Parallel II: Dark Matter models

Président de session: Bryan Zaldivar (LAPTh, Annecy-le-Vieux)

Korsmeier_DSU18.pdf

15:20 Supersymmetric dark matter by GAMBIT

Is supersymmetry loosing ground as a compelling explanation for dark matter? Or is there still enough experimental evidence to support our faith in supersymmetric dark matter? In search of quantitative answers, focusing on dark matter properties, I review the latest GAMBIT results for various supersymmetric models covering the CMSSM, NUHM1 and 2, MSSM7 and MSSM9.

Orateur: Csaba Balazs (Monash University)

SUSY-GAMBIT.pdf

15:40 LHC and dark matter signals motivated by the $\mu\nu$SSM

Orateur: Daniel Lopez-Fogliani

lopez-fogliani-DSU2018.pdf

16:00 → 16:30 Coffee break

16:30 → 18:10 Parallel I: Direct detection

Président de session: Doojin Kim

20180625DSU_DANAE_SHI.pdf

16:30 Direct dark matter search with DEAP-3600

DEAP-3600 is a single-phase liquid-argon Dark Matter direct detection experiment located 2 km underground at SNOLAB, in Sudbury, Canada. With a 1 tonne fiducial mass, the target sensitivity to spin-independent scattering of 100 GeV weakly interacting massive particles (WIMPs) is 10^{-46} cm^2. The detector was designed and built to reach a background level of less than 0.6 events in 3 tonne-years exposure. This included designing all parts of the detector to prevent or veto backgrounds, radio-purity screening for all detector materials, working with suppliers to source radio-pure materials, and using construction techniques that limit contaminations with radio-isotopes. The largest remaining background - beta decays from Ar-39 - is mitigated offline through pulse shape analysis. DEAP-3600 has been taking physics data since late 2016. This talk presents first results and the status of the experiment.

Orateur: Tina Pollmann (Technische Universität München)

DSU2018_Pollmann.pdf

16:50 Low-mass dark matter search with the CRESST-III experiment

Orateur: Johannes Rothe

rothe_DSU.pdf

17:10 DANAE - a new experiment for direct dark matter detection with DEPFET silicon detector.

Orateur: Hexi Shi

20180625DSU_DANAE_SHI.pdf

17:30 Search for dark matter with the SABRE experiment

The Sodium-iodide with Active Background REjection (SABRE) experiment is designed to search for the annual modulation of dark matter interaction rate with NaI(Tl) crystals. The experiment will also be able to perform a conclusive model-independent test of the notorious DAMA/LIBRA annual modulation signal. This signal is compatible with the WIMP-nucleon scattering hypothesis, but it is in contrast with observations from different-target dark matter experiments. SABRE will perform a high sensitivity search using NaI(Tl) crystals with unprecedented radio-purity operated inside a liquid scintillator veto for active background rejection. The project comprises twin detectors located in the northern and southern hemispheres to identify any possible contribution to the modulation from seasonal or site-related effects.
In the first phase of the experiment, the SABRE Proof-of-Principle (PoP), a single 5 kg crystal detector is hosted in a liquid scintillator filled vessel at the Laboratori Nazionali del Gran Sasso. This phase is underway with the aim to measure the crystal background, to test the active background rejection system, and to validate the SABRE concept.
This talk will illustrate the concept of the SABRE experiment and will present the latest estimate of the background for the SABRE Proof-of-Principle. Assuming such background model, the sensitivities of the experiment to spin-independent WIMP-nucleon scattering and to the DAMA/LIBRA modulation are assessed.

Orateur: Francesco Nuti (The University of Melbourne)

sabre_2018_06_25.pdf

17:50 Signal Diversity in Dark Matter Searches from Information Geometry

Orateur: Thomas Edwards (GRAPPA, Amsterdam)

signaldiversity - Edwards.pdf

16:30 → 18:10 Parallel II: Dark Matter models

Président de session: Bryan Zaldivar (LAPTh, Annecy-le-Vieux)

Korsmeier_DSU18.pdf

16:30 Radiative corrections to the Relic Density in the IDM

The current experimental precision from PLANCK on the extraction of the relic abundance of Dark Matter calls for very precise prediction from the theory side to be able to extract meaningful information. In this study we compute the full set of radiative corrections entering the calculation of the relic density of Dark Matter in the Inert Doublet Model and weigh their impact on its prediction in well motivated regions of parameter space. The calculation is performed with the help of the SloopS code, an automatic code for predictions beyond leading order in cosmology, astrophysics and cosmology.

Orateur: Guillaume Chalons (LPSC-IN2P3-CNRS)

chalons_DSU_18.pdf

16:50 Moduli Portal Dark Matter

Supergravity and string theories usually have particles, such as a modulus, with only gravitational interactions. These moduli fields arise due to the flat directions in the above theories. We inspect the possibility that these moduli fields acting as a mediator between the dark sector and the Standard Model, from an effective field theory perspective. We show that in this scenario, dark matter can be efficiently produced via freeze-in mechanism during the reheating epoch. We delineate the regions where this portal is efficient by varying the modulus mass relative to the temperatures attained during the reheating process.

Orateur: Debtosh Chowdhury (CPHT, Ecole Polytechnique)

DSU_2018.pdf

17:10 Dynamical EW symmetry breaking via multiple bosonic seesaw

Orateur: Shohei Okawa (TUM, Munich)

multiseesaw_okawa_DSU.pdf

17:30 SuperIso Relic new extensions for direct and indirect detection

SuperIso Relic is a public computing program for the calculation of flavour observables and relic density in supersymmetry (MSSM and NMSSM). We present new extensions of the code dedicated to the calculation of dark matter direct and indirect detection constraints from the latest experiment results. After presenting the new features of the program in particular the treatment of the relevant uncertainties, I will show some exemplified results and implications.

Orateur: Glenn Robbins (CRAL)

superiso.pdf

17:50 Dark matter searches with cosmic-ray antideuteron and antihelium

Orateur: Michael Korsmeier

Korsmeier_DSU18.pdf

mardi 26 juin

09:00 → 11:00 Direct detection and dark matter candidates II

Président de session: Carlos Munoz (IFT, Madrid)

09:00 Recent results from Xenon

Orateur: Ranny Budnik

Xenon1T_DSU.pdf

09:40 Axion and ALP dark matter and searches

Orateur: Javier Redondo

inte.pdf

10:20 Dark Matter and the Strong CP problem

Orateur: Lawrence Hall

DSU 2018 Hall.pdf

11:00 → 11:30 Coffee break

11:30 → 12:50 Dark matter candidates III

Président de session: Abdelhak Djouadi (LPT Orsay)

11:30 DM and freeze-in

Orateur: Andreas Goudelis

AndreasDSUFreezeIn2018.pdf

11:50 SIMP and SIDM

Orateur: Hyun Min Lee

dsu2018-hmlee2.pdf

12:10 Long range interactions and dark matter

Dark matter interacting through a light mediator arises in many extensions of the Standard Model. This scenario has been proposed for several phenomenological reasons, in particular to enhance dark matter self-interactions and solve the putative discrepancies between collisionless cold DM and observations of galactic structures.
I will discuss several phenomenological consequences showing that a variety of indirect detection constraints (gamma-rays, CMB, anti-protons) severely constrain such model.
Then I will consider the possibility of an asymmetry in the dark matter sector. I will show that, contrary to the common lore, detectable annihilations occur even for large asymmetries. I will discuss the possibility to test this scenario with direct and indirect searches.

Orateur: Marco Taoso (INFN Torino)

MTaoso_DarkSide.pdf

12:30 Neutrino-nucleus scattering in COHERENT

Orateur: Rex Tayloe

RTayloeCOHdarkside18 (1).pdf

12:50 → 14:30 Lunch

14:30 → 16:10 Dark matter searches at colliders

Président de session: Fawzi Boudjema (LAPTh)

14:30 DM searches with monoX and other exotic searches at LHC

Orateur: Barbara Clerbaux

DSU_DMatLHC_Clerbaux.pdf

15:00 DM searches in SUSY and other UV complete models at LHC

Orateur: Francesco Conventi

FConventi_DSU2018_SF.pdf

15:30 Search for subGeV dark sector particles with NA64 experiment at the CERN SPS

Orateur: Mikhail Kirsanov

DM_NA64_DSU2018.pdf

15:50 Exotic particles NA62

Orateur: Mathieu Perrin-Terrin (CPPM, Marseille)

perrin-terrin_2018-06-26.pdf

16:10 → 16:30 Coffee break

16:30 → 17:50 Parallel I: Dark matter models at colliders

Président de session: Y. Mambrini

20180625DSU_DANAE_SHI.pdf

16:30 Use and limitations of simplified-model constraints from the LHC

Simplified models have become one of the standard methods to interpret searches for new physics at the LHC. They reduce full models with dozens of particles and a plethora of parameters to subsets with just a handful of new states. The virtue of simplified model spectra (SMS), namely that a full model decomposes into many different SMS, also defines their main challenge: depending on the complexity of the mass and decay patterns, a full model may not be fully reconstructed by SMS.

In this talk, I present SModelS, an automatised public tool for interpreting simplified model results from LHC SUSY searches. I explain the working principle and how SModelS can be used -standalone or interfaced with micrOMEGAs- to a) constrain SUSY and non-SUSY models of new physics and b) identify interesting channels for which no SMS results are available. Finally, I address the limitations of the approach, that is to what extent full models can indeed be constrained by SMS results.

Orateur: Sabine Kraml (LPSC Grenoble)

Kraml-DSU-final.pdf

16:50 Next-to-minimal dark matter at the LHC

We examine the collider signatures of a WIMP dark matter scenario comprising a singlet fermion and an SU(2) n-plet fermion, with a focus on n=3 and n=5. The singlet and n-plet masses are of the order of the electroweak scale. The n-plet contains new charged particles which will be copiously pair-produced at the LHC. Small mixing angles and near-degenerate masses, both of which feature naturally in these models, give rise to long-lived particles and their characteristic collider signatures. In particular, the n=5 model can be constrained by displaced lepton searches independently of the mixing angle, generically ruling out 5-plet masses below about 280 GeV. For small mixing angles, we show that there is a parameter range for which the model reproduces the observed thermal relic density but is severely constrained by disappearing track searches in both the n=3 and the n=5 cases. The n=3 model is further constrained by soft di-lepton searches irrespectively of whether any new particles are long-lived.

Orateur: Nishita Desai (L2C & LUPM)

DSU-2018.pdf

17:10 Scalar versus vector dark matter

We investigate and compare two simple models of dark matter (DM): a vector and a scalar DM. In the former case an extra gauged group factor $U(1)$ is introduced, and the DM is the corresponding massive gauge boson $A_X^\mu$. The $U(1)$ symmetry is spontaneously broken by a vacuum of an extra scalar complex field $S$. Dark charge conjugation $A_X^\mu\to -A_X^\mu$ with $S \to S^*$ is responsible for stabilization of DM. In the latter case the gauge group remains standard, but an extra scalar complex field $S$ is also introduced. The DM is an imaginary part of $S$ and the stabilizing symmetry is also the dark charge conjugation $S \to S^*$. In this case, in order to avoid spontaneous breaking, the $U(1)$ symmetry is broken explicitly, but softly, in the scalar potential. The possibility to disentangle the two models has been investigated.

Orateur: Bohdan Grzadkowski (University of Warsaw)

DSU_18_Grzadkowski.pdf

17:30 Flavourful $Z′$ portal for vector-like neutrino Dark Matter and $R_{K^{(∗)}}$

We discuss a flavourful $Z'$ portal model with a coupling to fourth-family singlet Dirac neutrino dark matter. In the absence of mixing, the $Z′$ is fermiophobic, having no couplings to the three chiral families, but does couple to a fourth vector-like family. Due to mixing effects, the Z′ gets induced couplings to second family left-handed lepton doublets and third family left-handed quark doublets. This model can simultaneously account for the measured $B$-decay ratios $R_K$ and $R_{K^*}$ and for the observed relic abundance of dark matter. We identify the parameter space where this explanation is consistent with existing experimental constraints from dark matter direct and indirect detection, LHC searches, and precision measurements of flavour mixing and neutrino processes.

Orateur: Mathias Pierre (LPT Orsay)

DSU_Annecy_MP.pdf

16:30 → 17:50 Parallel II: Indirect dark matter searches

Président de session: Francesca Calore (LAPTh, CNRS)

Korsmeier_DSU18.pdf

16:30 Constraining Galactic dark matter with gamma-ray pixel counts statistics

The investigation of the composition of the extra-galactic gamma-ray background (EGB) is a powerful tool to search for dark matter signals in the gamma-ray sky. In the last few years, statistical analysis methods have been demonstrated to outperfom classic detection methods in decomposing the EGB. In particular, the 1-point photon counts statistics (1pPDF) permits to resolve the population of extra-galactic point sources and to decompose the diffuse components into Galactic foreground and isotropic background emissions.
For the first time, we extend this analysis to include a potential contribution from dark matter annihilating in the Galactic dark matter halo. In this contribution I will discuss the sensitivity reach of 1pPDF analysis for the dark matter thermally-averaged self-annihilation cross section when applied to eight years of Fermi-LAT data between 1 and 10 GeV.

Orateur: Silvia Manconi (University of Turin)

Manconi_DSU18.pdf

16:50 Probing the Nature of Dark Matter with Gamma Rays: Prospects for the Cherenkov Telescope Array at the Galactic Center

Revealing the nature of dark matter is one of the most riveting open tasks of modern astronomy and cosmology. To this end, observing and analyzing high-energy gamma-rays provides a promising and highly-effective tool which is, in particular, well-suited to constrain Weakly Interacting Massive Particle (WIMP) models.
Being currently in its pre-construction phase, the Cherenkov Telescope Array (CTA) will soon observe the high-energy gamma-ray sky in the 20 GeV - 300 TeV energy range. Thus, it will open the possibility to explore the parameter space of heavy dark matter (above 100 GeV) with unprecedented sensitivity.
One of the main targets for searches for signals of dark matter annihilation or decay is the center of our Galaxy. Due to its lower energy threshold and significantly larger effective area when compared to the current generation of ground-based Cherenkov telescopes, the CTA is expected to be sensitive to diffuse astrophysical emission which is present in that region.
In this talk, we present the status of the collaboration effort to estimate the sensitivity of CTA to various diffuse gamma-ray components in the surroundings of the Galactic Center. Moreover, based on the astrophysical emission observed with the LAT at lower energies, we report on the impact of these diffuse astrophysical emission backgrounds on dark matter searches and suggest promising data analysis and observational strategies for the upcoming CTA data.

Orateurs: Christopher Eckner (University of Nova Gorica), for the CTA Consortium

DM_at_GC_DSU_2018_Eckner.pdf

17:10 Constraining TeV-scale dark matter with cosmic-ray antiprotons

osmic-ray observations provide a powerful probe of dark matter annihilation in the Galaxy. In this paper we derive constraints on heavy dark matter from the recent precise AMS-02 antiproton data. We consider all possible annihilation channels into pairs of standard model particles. Furthermore, we interpret our results in the context of minimal dark matter, including higgsino, wino and quintuplet dark matter. We compare the cosmic-ray limits to limits from γ-ray observations of dwarf spheroidal galaxies and, for the specific case of minimal dark matter, to limits from γ-line observations of the Galactic center. While the latter limit is highly dependent on the dark matter density distribution and only excludes a thermal wino for cuspy profiles, the cosmic-ray limits are more robust, strongly disfavoring the thermal wino dark matter scenario even for a conservative estimate of systematic uncertainties.

Orateur: Dr Jan Heisig (RWTH Aachen University)

Heisig_DSU2018_Annecy.pdf

17:30 Astrophysical background and dark matter implication based on latest AMS-02 data

The cosmic ray(CR) positrons and antiprotons are often regarded as the products of collisions of CR nucleons with the interstellar medium. However this conclusion is challenged by recent experimental data. In this work, we choose the latest AMS-02 data to analyze the astrophysical background of CR positrons and antiprotons based on the GALPROP code for CR propagation and QGSJET-II-04 for hadronic CR interactions. The results show that in low energies the flux of CR antiprotons is consistent with AMS-02 data, and the over-predicted flux of CR positrons is well reduced in a diffusion model combining the re-acceleration and convection terms.
Using this model, the calculated flux of CR protons is consistent with AMS-02 data with the hardening feature above 330 GeV. Based on this model, using the total fluxes of CR electrons and positrons from AMS-02, interpretation of dark matter annihilation on the positron excess are also analyzed.

Orateur: Hong-Bo Jin (National Astronomical Observatories, Chinese Academy of Sciences)

DSU2018_HongBo_Jin.pdf

18:30 → 20:30 Reception at Annecy-le-Vieux Townhall

mercredi 27 juin

09:00 → 10:50 Dark matter indirect detection I

Président de session: Pierre SALATI (Laboratoire d'Annecy-le-Vieux de Physique Théorique LAPTH)

09:00 Multimessenger dark matter searches

Orateur: Marco Regis

DSU_Regis.pdf

09:40 PAMELA experiment: cosmic rays deep inside the heliosphere

Orateur: Riccardo Munini

RiccardoMuniniAnnecyPresentation.pdf

10:05 Antinuclei in cosmic rays

Orateur: Philip Von Doetinchen

1806_antideuteron_dsu_pvd.pdf

10:30 Indirect detection with antiprotons

Orateur: Mathieu Boudaud

DSU_2018_mathieu_boudaud.pdf

10:50 → 11:10 Coffee break

11:10 → 13:00 Dark matter indirect detection II

Président de session: Prof. Keith Olive (University of Minnesota)

11:10 CALET Results

Orateur: Pier Simone Marrocchesi

2018-06-27-DSU-Marrocchesi_v2.pdf

11:40 DAMPE Results

Orateur: Li Xiang

DAMPE-DSU2018.pdf

12:10 IceCube observations on the cosmos

IceCube, the cubic-kilometre neutrino telescope at the South Pole, is observing the sky with sensors embedded at more than 1.5 km depth. We describe recent findings of the experiment in standalone and in multi-messenger mode concerning time-dependent and independent searches of cosmic-ray sources. We also describe the results on indirect dark matter searches.

Orateur: Prof. Teresa Montaruli (University of Geneva)

DSU2018_montaruli.pdf

12:40 Indirect Search for Dark Matter with the ANTARES and KM3NeT Neutrino Telescopes

The ANTARES detector is the largest water Cherenkov neutrino telescope in the Northern hemisphere, installed in the Mediterranean Sea offshore France. It has been continuously taking data for more than ten years.

One major goal of ANTARES is the search for high energy neutrinos potentially produced by self-annihilation of Dark Matter particles trapped in massive objects such as the Sun or the Galactic Centre. Latest results of ANTARES on the indirect search for Dark Matter towards the Sun, the Earth and the Galactic Centre are presented. In particular, the results obtained by ANTARES on Dark Matter searches towards the Galactic Centre lead to the most stringent limits on the annihilation cross-sections for high mass WIMPs.

Finally, preliminary sensitivities on indirect search for Dark Matter with KM3NeT, the next generation neutrino telescope already under construction in the Mediterranean Sea, are also presented.

Orateur: Vincent Bertin (CPPM)

Bertin-DSU18.pdf

13:00 → 14:30 Lunch

14:30 → 15:10 Dark matter indirect detection III

Président de session: B. Gradkowski

14:30 X-ray polarimetry

Orateur: Francesca Day

Day_Annecy.pdf

14:50 Dark energy stars

Orateur: Paolo Gondolo

15:10 → 19:00 Excursions

jeudi 28 juin

09:00 → 11:00 Cosmology I

Président de session: Laura Lopez Honorez (Univ. Libre de Bruxelles Belgium)

09:00 Cosmological probes of dark matter

Orateur: Francis-Yan Cyr-Racine

DSU_cyr-racine_2018.pdf

09:40 Cosmology and neutrinos

Orateur: Yvonne Wong

yyyw.pdf

10:20 Status of Inflationary models after PLANCK

Orateur: Fabio Finelli

Finelli_Annecy.pdf

11:00 → 11:30 Coffee break

11:30 → 13:00 Cosmology II

Président de session: Jan Hamann (CERN)

11:30 LSST/Euclid future surveys

Orateur: Eric Aubourg

LSST-Euclid-Annecy-Jun2018.pdf

12:10 Cluster cosmology with the NIKA2 camera at the IRAM 30-m telescope

The main limiting factor of cosmological analyses based on thermal Sunyaev-Zel’dovich (SZ) cluster statistics comes from the bias and systematic uncertainties that affect the estimates of the mass of galaxy clusters. High-angular resolution SZ observations at high redshift are needed to study a potential redshift dependence of the cluster mass-observable scaling relation used in SZ cosmological analyses.
The NIKA2 camera is a new generation continuum instrument installed at the IRAM 30-m telescope. The combination of a large field of view (6.5 arcmin), a high angular resolution (17.7 arcsec), and a high-sensitivity of 8 mJy.s1/2 at 150 GHz provides the NIKA2 camera with unique SZ mapping capabilities. The NIKA2 SZ observation program will allow us to observe a large sample of clusters (50) at redshifts between 0.5 and 1.

I will present the characterization of the first NIKA2 SZ observations of a galaxy cluster at the IRAM 30-m telescope. I will then describe the ongoing SZ observation program with the NIKA2 camera and emphasize the synergy between the high quality NIKA2 SZ and XMM-Newton X-ray data for the calibration of the mass-obervable scaling relation at high redshift.

Orateur: Frédéric Mayet (LPSC Grenoble)

Mayet-DSU18-NIKA2.pdf

12:30 Apollo

Orateur: James Battat

battat_APOLLO_DSU_2018.pdf

12:50 DSU 2019

Orateur: Daniel Lopez-Fogliani

DSU2019-Bueno-Aires.pdf

13:00 → 14:30 Lunch

14:30 → 16:10 Cosmology III

Président de session: Frédéric Mayet (LPSC Grenoble)

14:30 DM haloes, open problems, perspectives

Orateur: Arianna Di Cintio

Annecy_2018_dicintio.pdf

15:10 Innovative methods to probe new models of dark matter in Clusters of Galaxies

In a bid to unveil the illusive fundamental properties of dark matter, physicists are being forced to look beyond the standard model and develop both new theoretical models and observational methods. In this talk I shall present exciting new results from observations and state-of-the-art simulations that exploits the largest structures in the known Universe, galaxy clusters to study the the dark matter self-interaction cross-section in a whole new way. This fundamental property, which has the discriminatory power to rule out large swathes of dark matter models has become of great interest in the last decade and these results could be another step closer to understanding exactly what this mysterious matter could be.

Orateur: David Harvey (EPFL)

DarkSideUniverse.pdf

15:30 A fresh look into the interacting dark matter scenario

Orateur: Laura Lopez Honorez

DSU-18-LLH.pdf

15:50 Role of the SM Higgs boson in the DM searches at colliders

I show that the SM Higgs boson can play an important role for the fermion or vector dark matter with Higgs portal interactions, because of the SM gauge invariance and unitarity, unlike the usual simplified models that includes only the singlet scalar mediator. I demonstrate how the ATLAS and the CMS bounds from the mono jet + missing $E_T$ and $t\bar{t} $ + missing $E_T$ on the DM models are modified when the effects of the SM Higgs boson is correctly included. Then I will discuss prospects for discovery and the spin discrimination of these DM models at the current and the future high energy colliders.

Refs: Based on arXiv:1712.05123,arXiv:1610.03997 (and also arXiv:1705.02149, arXiv:1701.04131, arXiv:1506.06556 )

Orateur: Pyungwon Ko (KIAS)

DSU2018_pko_1.pdf

16:10 → 16:40 Coffee break

16:40 → 18:40 Parallel I: Cosmology

Président de session: Pasquale Dario Serpico (LAPTh, Annecy-le-vieux)

20180625DSU_DANAE_SHI.pdf

16:40 Optimal and accurate cosmology from the Dark Energy Survey and beyond

We are in the midst of an exciting time for understanding the dark sector of the Universe. Current and upcoming projects, including DES, LSST, and Euclid are observing an unprecedented number of galaxies and other astrophysical objects. It is critical to develop robust strategies that fully utilize this statistical power to extract cosmological information. I will present recent work connecting these observations to the underlying cosmological and astrophysical processes. In particular, I will discuss an analytic framework that maps between the behavior of dark matter and dark energy and the observed positions and shapes of galaxies (or any other luminous tracer). I will describe how this framework can be used in joint analyses of multiple probes or data sets, highlighting recent results from DES as an example.

Orateur: Jonathan Blazek (EPFL and OSU)

Blazek_DSU2018_upload.pdf

17:00 Cosmology with recent and future massive spectroscopic surveys: eBOSS and 4MOST/CRS

Massive spectroscopic surveys are a key-component of the cosmological experiments, constraining the dark energy with the measurement of the Baryon Acoustic Oscillation (BAO) scale, but also the General Relativity on cosmological scales through redshift-space distortion (RSD) measurements, or the summed mass of all neutrino species.
I will first present latest results from the SDSS/eBOSS survey (2014-2019, ~1 million spectra over 7500 deg2), which is focusing on the [0.6,2.2] redshift range. I will then introduce the 4MOST/CRS survey (2021-2026) which will observe 20 million spectra for redshifts within 0 and 3, over 14,000 deg2, to map the three-dimensional matter distribution. 4MOST/CRS will thus be a reference survey over the Southern Sky.

Orateur: Anand Raichoor (EPFL)

Raichoor_DSU_28Jun2018.pdf

17:20 Fuzzy dark matter and Planck

Orateur: Arata Aoki

3_aoki_DSU2018.pdf

17:40 Modified dark matter: relating dark energy, DM and baryonic matter

Orateur: Y. Jack Ng

14thDSU.pdf

18:00 Birkhoff theorem in theories with torsion

In this talk I will present some recent results about the Birkhoff theorem in theories of gravity with non-vanishing torsion. Specifically, I will consider the most general quadratic Lagrangian, which depends on 9 parameters. Then, I will show that under some combination of the parameters, we can new theories in which the Birkhoff theorem holds. Moreover, other combinations allow us to find vacuum solutions different from Schwarzschild, that were not present in previous literature. Finally, I will explain the relation of these results with the stability conditions in these theories.

Orateur: F.J. Maldonado Torralba (University of Cape Town)

DSU2018 Final Presentation FJMT.pdf

16:40 → 18:40 Parallel II: Dark matter direct detection

Président de session: Hyun Min Lee

Korsmeier_DSU18.pdf

16:40 One loop direct detection

Orateur: Natsumi Nagata

Nagata.pdf

17:00 Direct detection of exothermic dark matter with light mediator

In this talk, we study the possible models trying to reconcile the tension between the CDMS-Si signals and null experiments. In particular, we focus on the models with the following properties: isospin-violating couplings, exothermic scatterings, and/or a light mediator. In the light of the latest constraints from LUX, PandaX-II, XENON1T, CDMSlite and PICO-60, we find that, for almost all the considered models, the predicted CDMS-Si signal regions are either severely constrained or completely excluded, including the previously promising Xe-phobic exothermic DM models with/without a light mediator.

Orateur: Dr Da Huang (University of Warsaw)

DMDD_DSU.pdf

17:20 Boosted dark matter and surface detector

Orateur: Jong-Chul Park

SurfaceDetectors_JCPark_DSU.pdf

17:40 Direct detection of mirror dark matter

Orateur: Robert Foot

2018DSUFOOT.pdf

18:00 Surrogate Models for Direct Dark Matter Detection

This talk will introduce the use of surrogate model techniques for direct detection of dark matter. We have developed a tool, RAPIDD, that replaces the exact calculation of the dark matter differential rate (which in general involves up to three nested integrals) with a much faster parametrization in terms of ordinary polynomials of the dark matter mass and couplings, obtained in an initial training phase. Based on the work presented in arXiv:1802.03174, we explore the need and benefit of doing direct detection calculations differently, increasing speed vastly and sacrificing very little in terms of accuracy. We will exhibit the general analysis that these methods enable us to do, requiring larger than usual dimensionality and including astrophysical uncertainties. RAPPID is particularly well suited to analysis that demands high-dimensional parameter spaces and a large number of evaluations.

Orateur: Andrew Cheek (Durham, IPPP)

cheek_dsu.pdf

18:20 Inelastic boosted dark matter at protoDUNE

Orateur: Doojin Kim

Presentation_DSU2018_DoojinKim.pdf

19:00 → 22:00 Social dinner

vendredi 29 juin

09:00 → 11:00 Gravitational Waves and Black Holes

Président de session: Subhendra Mohanty (Physical Research Laboratory, Ahmedabad)

09:00 LIGO/Virgo Results

Orateur: Loic Rolland

2018_06_29_ConfDSU_GWresults_Rolland.pdf

09:40 Perspectives of gravitational waves: LISA &PTA

Orateur: Alberto Sesana

Sesana_Annecy18.pdf

10:20 Primordial Black holes

Orateur: Misao Sasaki

PBH_DSU18.pdf

11:00 → 11:30 Coffee break

11:30 → 13:10 Gravitational Waves and Modified Gravity

11:30 Gravitational-Wave Signals in Extended Theories of Gravity

Once the Einsteinian paradigm is abandoned, the phenomenology of neutron stars changes dramatically since neutron-star masses can be much larger than their General Relativity counterparts. Consequently, the total energy available for radiating gravitational waves could be of the order of several solar masses, and thus a merger of these stars constitutes a privileged wave source. This opens the door to a careful study of novel gravitational-wave signals as extracted from extended theories of gravity.

Orateur: Dr Álvaro de la Cruz-Dombriz (University of Cape Town)

DSU2018_DOMBRIZ_29June2018final.pdf

11:50 Cosmological Backgrounds of Gravitational Waves

Orateur: Daniel G. Figueroa

DaniFigueroa_DSU2018.pdf

12:30 Modified Gravity: the current landscape

Orateur: Tessa Baker

Annecy2Baker.pdf

13:10 → 14:30 Lunch

14:30 → 16:10 Parallel I: Particle Cosmology

14:30 Asymptotic Scale Invariance, Electroweak Vacuum Stability and Higgs Inflation

We discuss a possibility that our electroweak vacuum is absolutely stable even if the top Yukawa coupling is larger than the critical value. Such a scenario can be realized without introducing new particles if we adopt a renormalization prescription which respects the asymptotic scale invariance at the quantum level. Instead, the theory becomes non-renormalizable and the perturbative unitarity is violated at some energy scale. We argue that the perturbative computation of the Higgs effective potential is still justified and hence the quantum scale invariance can actually stabilize our vacuum. We also discuss the Higgs inflation with uncertainties coming from the violation of the perturbative unitarity.

Orateur: Dr Kengo Shimada (EPFL)

1_KengoShimada-DSU2018.pdf

14:50 Are dark matter interactions ruled out?

Orateur: Deanna Hooper

2_DSU18_Hooper.pdf

15:10 CMB constraints on light primordial black holes

Orateur: Jan Hamann (CERN)

Hamann_DSU2018.pdf

15:30 Updated observational constraints on quintessence Dark Energy models

The recent GW170817 measurement favors the simplest Dark Energy models, such as a single scalar field. Quintessence models can be classified in two classes, freezing and thawing, depending on whether the equation of state decreases towards −1 or departs from it. In this work we put observational constraints on the parameters governing the equations of state of tracking freezing, scaling freezing and thawing models using updated data, from the Planck 2015 release, Joint Light-Curve Analysis and Baryonic Acoustic Oscillations. Because of the current tensions on the value of the Hubble parameter H0 , unlike previous authors, we let this parameter vary, which modifies significantly the results. Finally, we also derive constraints on neutrino masses in each of these scenarios.

Orateur: Jean-Baptiste Durrive (Univ. Nagoya)

4_AnnecyWorkshop2018_Durrive.pdf

14:30 → 16:10 Parallel II: Dark matter models II

Président de session: Cédric Delaunay

14:30 Baryogenesis from non-thermal wimp

Orateur: Ki-Young Choi

BaryogenesisNTPWIMP_Annecy.pdf

14:50 SIDM with a light mediator in a gauged U(1) Lmu-Ltau model

Orateur: Keisuge Yanagi

yanagi_DSU2018.pdf

15:10 Nonperturbative Effects in Late Time Dark Matter Phenomenology

Self-interacting dark matter is a promising candidate for solving the small-scale problems in the standard model of cosmology. A natural consequence of having self-interactions among dark matter particles is the Sommerfeld effect which can affect both the annihilation and self-scattering rates of dark matter particles. I shall show that as a result of the Sommerfeld effect, caused by a long-range off-diagonal interaction, the dark matter annihilation signal from the Milky Way center is preferentially enhanced by several orders of magnitude. This result can have important implication for indirect detection searches. I shall also explain this result with the help of simple particle exchange symmetry. The same interaction also predicts a faster dark matter halo cooling rate and a new drag force induced by large inelastic scattering. It could potentially modify the late time dynamics of the halos.

Orateur: Anirban Das (Tata institute of Fundamental Research)

dsu_talk_anirban.pdf

15:30 Enhancement of the dark matter abundance before reheating: thermal and non-thermal production

In the first stages of inflationary reheating, the temperature of the radiation produced by inflaton decays is higher than the commonly defined reheating temperature $T_R$. At these temperatures particle production can be significantly enhanced. Furthermore, in the earliest stages of reheating, before thermalization takes place, scattering of the inflaton decay products with momenta comparable to the inflaton mass can further enhance the particle production rate relative to the thermal one.

I will discuss these effects in a high scale supersymmetry model in which the only supersymmetric state below the inflationary scale is the gravitino, which plays the role of the dark matter particle. In such scenario, the thermal and non-thermal enhancement dominates over the dilution by the later generation of entropy near $T_R$, leading to a relic abundance that is sensitive to the maximum temperature of the Universe, set by the time scale of thermalization.

Orateur: Marcos A. Garcia Garcia (Rice University)

DSU2018_Marcos.pdf