Ultra-High-Frequency Gravitational Waves


Background plot generated at gwplotter.com

Goals of the initiative

The first direct detection of gravitational waves by the LIGO and VIRGO collaborations has spawned new avenues for the exploration of the Universe. Currently operating and planned gravitational wave detectors mostly focus on the frequency range below 10 kHz, where signatures from the known astrophysical sources are expected to be discovered. However, based on what happens with the electromagnetic spectrum, there may well be interesting physics to be discovered at every scale of the gravitational wave frequencies. Gravitational waves at frequencies higher than 10 kHz are bound to be sourced by some phenomenon involving beyond the Standard Model physics, such as exotic astrophysical objects or cosmological events in the early Universe. In particular, several cosmological sources - for instance preheating after inflation and phase transitions at high energies - would leave their imprint in the gravitational wave spectrum at frequencies around the GHz. Hence, the search for gravitational waves at frequencies above the LIGO/VIRGO range is a promising and challenging search for new physics, providing an opportunity to test many theories beyond the Standard Model, that could not be tested otherwise.

The UHF-GW (Ultra-High-Frequency Gravitational Wave) initiative promotes the creation of a network of researchers for the development of gravitational wave science in the frequency range above 10 kHz. We strongly believe that a fruitful collaboration between experimentalists and theorists is necessary to make progress in this quest and we facilitate it by organising meetings and workshops aimed at putting in contact these two worlds. One of the goals of the initiative is to support the testing phase of currently existing detector proposals and stimulate the technological developments necessary to come up with new schemes for gravitational wave detectors at frequencies above 10 kHz.

Technological roadmap announcement

The first step of this initiative has been a workshop held at ICTP in Trieste in 2019 (http://indico.ictp.it/event/9006/overview) that led to a review paper (https://arxiv.org/abs/2011.12414) in which the state of the art of the subject was summarised. See the section below for details.

One issue identified in Trieste was the need for technological development of the various detector schemes being currently considered. This announcement invites groups working on detector development to contribute to a roadmap defining the medium and long term objectives for such a program. The first stage necessary for us to coordinate such a plan is to gather information from interested groups about their current and planned technology via a questionnaire, for which you can find the link below.

Another point identified in the Trieste meeting is the importance of sharpening the science case for gravitational wave physics in the frequency band above 10 kHz. Hence, we also invite theory groups and researchers who would like to support this initiative to contribute to this questionnaire (link below), specifying the scientific reasons that make this subject relevant to their research.

The information collected in this process will form an important part of a future UHF-GW workshop, to be held online in October 2021. We encourage all interested scientists to complete the questionnaire by the end of May, and to forward this message to all the potentially interested collaborators.

The link to the questionnaire is https://forms.gle/VW9RgcytD1SJfjoe9.

It is proposed that this technology group within UHF-GW adopts a simple set of governance rules and a code of conduct. A draft version of this document is here.

Members of the initiative:

  • Nancy Aggarwal
    Affiliation: Center for Fundamental Physics; Centre for Interdisciplinary Exploration and Research in Astrophysics (CIERA); Department of Physics and Astronomy, Northwestern University.
    Contact: nancy[dot]aggarwal[at]northwestern[dot]edu
  • Mike Cruise
    Affiliation: University of Birmingham.
    Contact: cruiseam1[at]gmail[dot]com
  • Valerie Domcke
    Affiliation: CERN; Laboratory for Particle Physics and Cosmology, EPFL, Lausanne.
    Contact: valerie[dot]domcke[at]cern[dot]ch
  • Francesco Muia
    Affiliation: The Stephen Hawking Centre for Theoretical Cosmology; DAMTP, University of Cambridge.
    Contact: fm538[at]cam[dot]ac[dot]uk
  • Fernando Quevedo
    Affiliation: The Stephen Hawking Centre for Theoretical Cosmology; DAMTP, University of Cambridge.
    Contact: fq201[at]damtp[dot]cam[dot]ac[dot]uk
  • Andreas Ringwald
    Affiliation: Deutsches Elektronen-Synchrotron DESY, Hamburg.
    Contact: andreas[dot]ringwald[at]desy[dot]de
  • Jessica Steinlechner
    Affiliation: Maastricht University; Nikhef, Amsterdam; SUPA, School of Physics and Astronomy, University of Glasgow.
    Contact: jessica[dot]steinlechner[at]maastrichtuniversity[dot]nl
  • Sebastian Steinlechner
    Affiliation: Maastricht University; Nikhef, Amsterdam.
    Contact: s[dot]steinlechner[at]maastrichtuniversity[dot]nl

Challenges and Opportunities of High Frequency Gravitational Wave Detection

Details of our October 2019 workshop in Trieste can be found here:

http://indico.ictp.it/event/9006/

The workshop was summarised in the following paper:

https://arxiv.org/abs/2011.12414

Keynote speakers

Short contributions

Summary and final discussion

Keynote speakers

Prof. Odylio D. Aguiar, Instituto Nacional de Pesquisas Espaciais (INPE), Sao Paulo, Brazil
The Schenberg Gravitational Wave Antenna: a resonant mass spherical antenna
Slides
Video

Prof. Andreas Bauswein, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
Neutron star mergers and kHz gravitational wave emission
Slides
Video

Prof. Mike Cruise, School of Physics and Astronomy, University of Birmingham, Birmingham, UK
Strategies for GW science above 1GHz
Slides
Video

Prof. Daniel G. Figueroa, Instituto de Fisica Corpuscular (IFIC), University of Valencia, Valencia, Spain
Introduction to cosmological sources of high frequency gravitational waves
Slides
Video

Prof. Andrew Geraci, Center for Fundamental Physics, Department of Physics and Astronomy, Northwestern University, Evanston, USA
Detecting high-frequency gravitational waves with optically levitated sensors
Slides
Video

Dr. Maxim Goryachev, ARC Centre of Excellence for Engineered Quantum Systems, Department of Physics, University of Western Australia, Crawley, Australia
High Frequency Gravitational Wave Detection with Bulk Acoustic Devices: From Technology to First Data
Slides
Video

Prof. Hartmut Grote, Cardiff University, Cardiff, UK
Experimental upper limits on (ultra) high frequency gravitational waves and prospects for more: Magnetic conversion detection and correlated interferometry
Slides
Video

Prof. Mark Hindmarsh, Department of Physics and Helsinki Institute of Physics, Helsinki, Finland; Department of Physics and Astronomy, University of Sussex, Brighton, UK
Gravitational Waves from Phase Transitions
Slides
Video

Prof. David Ottaway, Department of Physics, School of Physical Sciences and The Institute of Photonics and Advanced Sensing (IPAS), University of Adelaide, Adelaide, Australia; Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav)
OzGrav HF: A detector for studying nuclear matter at extreme pressure, temperature and density
Slides
Video

Prof. Marco Peloso, Dipartimento di Fisica e Astronomia Galileo Galilei, Università di Padova, Padova, Italy; INFN, Sezione di Padova, Italy
Gravitational Waves from Inflation and Primordial Black Holes
Slides
Video

Short contributions

Dr. Francisco Torrenti, Department of Physics, University of Basel, Basel, Switzerland
Gravitational waves from preheating: parameter dependence
Slides
Video

Dr. Toby Opferkuch, CERN, Geneva, Switzerland
Gravitational Imprints of Flavour Hierarchies
Slides
Video

Prof. Seyed M. S. Movahed, Department of Physics, Shahid Beheshti University, Tehran, Iran
A pipeline for searching Stochastic Gravitational Wave by Pulsar Timing Residuals
Slides
Video

Summary and final discussion

Discussion: How to move forward?
Slides
Video