International Summer Research Program in Gravitational-Wave Physics:
Research Experiences for Undergraduates around the world

AstroParticule et Cosmologie, Université Paris 7 - Denis Diderot
  • Wavelet graph for the detection of coalescing binary chirps:
    Coalescing binaries of neutron star and/or black hole are to be one of the most promising sources of gravitational waves. Data analysis pipelines are currently under development in preparation for the next scientific runs of Advanced LIGO and Virgo. In this project, we will explore the potential of wavelet graphs to detect weak chirping signals from coalescing binaries.
    Mentor: Eric Chassande-Mottin
    Related Project 2014: "Wavelet Graph Searches for Gravitational Chirps"
  • New clustering scheme for the detection of chirp-like signals:
    Coherent WaveBurst (cWB) is one of the pipelines developed for the search for transient GW. cWB has been successfully applied in the context of "eyes wide open" all-sky and all-time searches for GW transients. A new and improved version of cWB is currently under development and will be ready for the up-coming data takings. cWB relies on sensor array techniques (analogous to beam-forming used in radio astronomy, for instance) to analyze coherently data streams from multiple GW detectors. In a nutshell, cWB performs the wavelet decomposition of the coherently combined data. Significant wavelet coefficients are then clustered to form GW "events". For this project, we propose to implement and test a new clustering scheme that improves cWB sensitivity to a specific class of GW sources such as coalescing binaries of neutron-star and/or black-hole (in short, CBC for compact binary coalescences). CBC are often considered one of the most promising sources of GW. The last minutes before the binary merges give rise to the emission of an intense burst of GW. From the accurate modeling of the binary dynamics, it can be predicted that the GW waveform is a quasi-periodic signal or chirp. The chirp frequency sweeps towards high values according to a power law at first order. The basic idea is to design a clustering scheme that incorporates this morphological information.
    Mentor: Eric Chassande-Mottin
    Related Project 2014: "Wavelet Graph Searches for Gravitational Chirps"
  • Electromagnetic follow-up strategies for advanced GW detectors:
    The field of gravitational-wave physics will enter soon a new era with the advent of a new generation of detectors. Thanks to a ten-fold increase in sensitivity with respect to the previous generation, the advanced LIGO and Virgo detectors will probably make the first direct detection of gravitational waves. Most likely sources are very energetic astrophysical events like core collapse supernovae or mergers of neutron-star and/or black hole binaries. The observation of a electromagnetic counterpart will likely be a key ingredient to confirm the astrophysical nature of a gravitational-wave candidate event. The idea is to evaluate possible scenarios for the future electromagnetic follow-up programs using a global network of wide-field robotic telescopes, X-ray and/or Gamma-ray observatories, etc.
    Mentor: Eric Chassande-Mottin
    Related Project 2012: "End to End Simulations of Gravitational Wave Electromagnetic Follow-Up Program"
  • Development and data analysis of an optical simulator for eLISA:
    eLISA (formerly LISA) is a space mission aiming at detecting gravitational waves, using 3 distant satellites forming a Michelson-like interferometer.  With 1 million kilometers between the spacecraft, one of the main challenges of testing the required eLISA technologies is to produce representative optical signals. Especially, key algorithms such as the Time Delay Interferometry (TDI) and arm-locking techniques make use of the slowly evolving propagation delays (about 3 s) and of the redundancy of the laser frequency noise measurements. In order to study the influence of the opto-electronic devices (such as photodiodes, phasemeters, etc.) on the reconstruction algorithms, our team at the APC is currently developing an optical bench to produce eLISA-like interferometric signals.  The student will participate in and contribute to different aspects of this project: characterization and optimization of the optical setup, design and realization of improved control electronics, development of control software, analysis of the recorded signals and comparisons with the expected performance.
    Mentor: Hubert Halloin
    Related Project 2011: "Noise Reduction for LISA On Table (LOT)"
    Related Project 2012: "Characterization of Fiber Optics Devices for LASIC II"

Past Projects: AstroParticule et Cosmologie, Université Paris 7 - Denis Diderot
  • Searching for gravitational-wave bursts with low latency:
    Low-latency data analysis will be of particular importance for the advanced detector era as it will enable the follow-up of remarkable gravitational-wave events with other observatories with access to electromagnetic or neutrino spectra, such as from optical telescopes or large-scale neutrino detectors. The student would contribute to the development of low-latency data analysis pipelines.
    Mentor: Eric Chassande-Mottin
  • Data analysis for the Virgo and LIGO detectors:
    In June 2009, Virgo and LIGO will start a long-term science run. Part of the analysis of the data will be performed in real-time with the objective to send trigger alerts to other observatories. The Virgo group at APC contributes to this work through several projects. In particular, searches for an optical counterpart (together with the robotic telescope TAROT) or for coincident high energy neutrinos (together with the neutrino telescope ANTARES) are considered. We propose that the student participate in and contribute to one of these projects.
    Mentor: Eric Chassande-Mottin
    Related Project 2009: "Simulations of Gravitational Wave Generating Transient Objects on Telescope Images"
  • Multi-detector coherent event follow-up incorporating a clustering algorithm:
    Gravitational Wave burst detection algorithms typically rely on the hypothesis that the burst signal changes slowly with frequency, in which case the signal can be decomposed into a small number of wavelets with constant frequency. This justifies the use of sine-Gaussian templates in the Omega pipeline, one of the algorithms used in LIGO-Virgo burst searches. There are, however, plausible scenarios in which the burst frequency might evolve rapidly, such as in the merger phase of a binary black hole and/or neutron star coalescence. In such cases, the local stationarity of sine-Gaussians induces performance losses, due to the mismatch between the template and the actual signal. We have proposed an extension of the Omega pipeline based on chirplet-like templates. Chirplets incorporate an additional parameter, the chirp rate, to control the frequency variation. The proposed extension was limited to a single-detector analysis and had no clustering of extended events. We will examine the possibility of a multi-detector coherent event follow-up and the implementation of an adequate clustering algorithm for chirplets.
    Mentor: Eric Chassande-Mottin
    Related Project 2011: "Significant trigger clustering algorithm for the chirplet omega pipeline"

Past IREU Projects
Other Prior Projects