Publications associées à Pôle de l'écliptique

Highly Active Ice‐Nucleating Particles at the Summer North Pole

The amount of ice versus supercooled water in clouds is important for their radiative properties and role in climate feedbacks. Hence, knowledge of the concentration of ice-nucleating particles (INPs) is needed. Generally, the concentrations of INPs are fo ...

2022

Evolution of critical buckling conditions in imperfect bilayer shells through residual swelling

Pedro Miguel Nunes Pereira de Almeida Reis, Matteo Pezzulla, Dong Yan, Anna Lee

We propose and investigate a minimal mechanism that makes use of differential swelling to modify the critical buckling conditions of elastic bilayer shells, as measured by the knockdown factor. Our shells contain an engineered defect at the north pole and ...

ROYAL SOC CHEMISTRY2019

Gaia Data Release 1 Summary of the astrometric, photometric, and survey properties

Stephan Morgenthaler, Mikaël Martino, Shuangqing Liao

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illu ...

EDP Sciences2016

Renormalization and blow up for wave maps from $S^2 \times \mathbb{R}$ to $S^2$

Sohrab Mirshams Shahshahani

We construct a one parameter family of nite time blow ups to the co-rotational wave maps problem from

S^2\times R

to

S^2

parameterized by

\nu \epsilon (\frac{1}{2},1]

. The longitudinal function

u(t,\alpha)

which is the main object of study will be ...

2016

All-particle cosmic ray energy spectrum measured with 26 IceTop stations

Shirit Cohen, Mathieu Ribordy, Matthias Wolf, Xiaoxia Bai

We report on a measurement of the cosmic ray energy spectrum with the IceTop air shower array, the surface component of the IceCube Neutrino Observatory at the South Pole. The data used in this analysis were taken between June and October, 2007, with 26 su ...

Elsevier Science Bv2013

IceTop: The surface component of IceCube

Shirit Cohen, Mathieu Ribordy, Matthias Wolf, Xiaoxia Bai

IceTop, the surface component of the IceCube Neutrino Observatory at the South Pole, is an air shower array with an area of 1 km(2). The detector allows a detailed exploration of the mass composition of primary cosmic rays in the energy range from about 10 ...

Elsevier Science Bv2013

Diffuse gamma-ray constraints on dark matter revisited I: the impact of subhalos

Steve Blanchet

We make a detailed analysis of the indirect diffuse gamma-ray signals from dark matter annihilation in the Galaxy. We include the prompt emission, as well as the emission from inverse Compton scattering whenever the annihilation products contain light lept ...

Iop Publishing Ltd2012

Design and performance of the South Pole Acoustic Test Setup

Mathieu Ribordy

The South Pole Acoustic Test Setup (SPATS) was built to evaluate the acoustic characteristics of the South Pole ice in the 10-100 kHz frequency range, for the purpose of assessing the feasibility of an acoustic neutrino detection array at the South Pole. T ...

2012

Background studies for acoustic neutrino detection at the South Pole

Shirit Cohen, Mathieu Ribordy, Matthias Wolf, Xiaoxia Bai

The detection of acoustic signals from ultra-high energy neutrino interactions is a promising method to measure the flux of cosmogenic neutrinos expected on Earth. The energy threshold for this process depends strongly on the absolute noise level in the ta ...

2012

The IceCube data acquisition system: Signal capture, digitization, and timestamping

Xiaoxia Bai

IceCube is a km-scale neutrino observatory under construction at the South Pole with sensors both in the deep ice (InIce) and on the surface (IceTop). The sensors, called Digital Optical Modules (DOMs). detect, digitize and timestamp the signals from optic ...

2009

Alignment and signed-intensity anomalies in WMAP data

Pierre Vandergheynst, Yves Wiaux

Significant alignment and signed-intensity anomalies of local features of the cosmic microwave background (CMB) are detected on the three-year WMAP data, through a decomposition of the signal with steerable wavelets on the sphere. In addition to identifyin ...

2007

Steerable wavelet analysis of CMB structures alignment

Pierre Vandergheynst, Yves Wiaux

This paper reviews the application of a novel methodology for analysing the isotropy of the universe by probing the alignment of local structures in the CMB. The strength of the proposed methodology relies on the steerable wavelet filtering of the CMB sign ...

2006

Global universe anisotropy probed by the alignment of structures in the cosmic microwave background

Pierre Vandergheynst, Yves Wiaux

We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet decomposition of the CMB signal on the sphere. The analysis ...

2006