Conveners
Plenary Session: Time Domain
- Shivani Bhandari (ASTRON)
Plenary Session: Astronomy
- Shivani Bhandari (ASTRON)
Plenary Session: The Square Kilometre Array
- Jessica Dempsey (ASTRON)
Plenary Session: Astronomy
- Jason Hessels (University of Amsterdam / ASTRON)
Plenary Session: Instrumentation
- Joeri van Leeuwen (ASTRON)
Plenary Session: Galaxy Evolution & Cosmology
- Pikky Atri (ASTRON)
Plenary Session: Galaxy Evolution & Cosmology
- Scott Trager (Kapteyn Astronomical Institute, University of Groningen)
Plenary Session: Astronomy
- Scott Trager (Kapteyn Astronomical Institute, University of Groningen)
Fast radio bursts (FRBs) are so crazily bright that they must be powered by uniquely energetic emission mechanisms. Identifying their physical nature requires good localisation of more detections, and broadband studies enabled by real-time telescope combinations. I will present the results from the Apertif FRB survey (ALERT) that ran 2019-2022. ALERT performed wide-field, fully coherent,...
Fast radio bursts (FRBs) are extragalactic radio transients of microsecond to millisecond duration, whose physical origin is largely unknown. Some FRBs are known to repeat, which rules out cataclysmic progenitor models for these sources. Repeating FRBs exhibit significantly different temporal widths and bandwidths as compared to the non-repeating sources. A potential explanation for these...
The mergers of two neutron stars are exceptional multi-messenger events including short gamma-ray burst (GRB), gravitational wave and kilonova/afterglow emission. These events enable us to probe fundamental physics in one of the most extreme environments in the Universe. A key outstanding question is the remnant’s nature: with its expected mass and rapid spin, it could either be a black hole...
Fast radio bursts (FRBs) are enigmatic millisecond-duration radio flashes with an extragalactic origin. FRBs sources can be divided into two populations: repeating and apparently non-repeating sources. The burst energy distribution from repeating FRB sources is an important diagnostic tool that can be used to better understand the emission process, cosmological applications, and the potential...
The current climate crisis has led to UN and EU regulations to reduce greenhouse gas emissions by 55% in 2030. Astronomers should lead this effort by example, as they are aware of the lack of a Planet B to live on.
In the Netherlands, the RvdA installed a working group to monitor and improve the sustainability of Dutch astronomy, including outreach & communication on this topic. Our kickoff...
As the intracluster medium (ICM) in galaxy clusters cools through the emission of X-ray radiation, it sinks down toward the central galaxy where it fuels the AGN. This AGN subsequently emits radio-mode feedback in the form of powerful jets of relativistic plasma which re-energize the ICM, completing the feedback cycle. Measurements of the energy injected by radio-mode feedback into the cluster...
We are working on is a work climate survey of Dutch astronomy, under the direction of the NWO tafel voor astronomie and would like to update the community on this and other activities.
WEAVE is the next-generation wide-field survey facility for the William Herschel Telescope (WHT). WEAVE will provide the instrument required for full scientific exploitation of the Gaia, LOFAR, and APERTIF surveys in the Northern Hemisphere. WEAVE is a multi-object and multi-integral-field-unit (IFU) facility utilizing a large, new 2-degree-diameter prime focus corrector at the WHT with a...
New phased array feed for the Westerbork synthesis radio telescope, Apertif, provides L-band continuum radio images of the sky with angular resolution and sensitivity significantly better than the previous state-of-art northern survey, the NRAO VLA Sky Survey (NVSS). We continue processing Apertif data and releasing it for the community.
In this work we mosaic together Apertif observations of...
The LOw Frequency ARray (LOFAR) is in many respects the world’s largest and most sensitive low-frequency radio telescope. LOFAR stretches across Europe, from Ireland to Latvia, with a dense core and 38 stations distributed throughout the Netherlands, as well as 14 additional stations located in 8 partner countries. The pan-European array is called the International LOFAR Telescope (ILT). ...
The recommendations from the most recent Decadal Survey on Astronomy and Astrophysics include a NASA-led probe-class X-ray telescope to be launched in the 2030s. I will discuss the mission concepts that are being developed as a response, with particular focus on SRON’s contribution to the observatories that will address the priority area “Unveiling the Drivers of Galaxy Growth”. Galaxy...
Despite its crucial role in shaping our understanding of galaxy formation and evolution, the low mass end of the high redshift galaxy mass function has so far remained largely unknown. This is specially true for the high redshift universe, where even the deepest surveys have been unable to probe this elusive galaxy population.
To address this challenge, we leverage the powerful...
Galaxy formation in the first billion years mark a time of great upheaval in our cosmic history: the first sources of light in the Universe, these galaxies ended the 'cosmic dark ages' and produced the first photons that could break apart the hydrogen atoms suffusing all of space starting the process of cosmic reionization. At the forefront of astronomical research, the past few years have...
Various feedback mechanisms, such as star formation, large-scale outflows, shocks or Active Galactic Nuclei, affect the shape and evolution of galaxies. Starburst galaxies, in particular, show exceptionally higher star-formation rates compared to regular galaxies (e.g. the Milky Way), indicating different physical conditions. Understanding how these physical conditions differ in starburst...
One of the most exciting frontiers in extragalactic astronomy is understanding how rapidly galaxies formed stars in the Early Universe. This involves us constraining the Star Formation Rate Density (SFRD) at z >~ 6. Given the much greater ease in surveying the z > 4 universe in the rest-UV, the SFRD at z > 4 is biased to the unobscured, less dusty sources. Recent work shows that the...
We present an empirical galaxy evolution model, investigating the co-evolution of dark matter halos, galaxies, and supermassive black holes using from z= 0 - 10. Our approach connects the evolution of dark matter structure with simple empirical prescriptions for baryonic processes, allowing us to reproduce key observations in the relationship between galaxies and their black holes.
To...
In the literature, large amount of work has been devoted to the study of the build-up of metals and dust in disc galaxies. However, most of these analyses are based on global galactic properties. Therefore, spatially resolved studies are crucial to provide more detailed information on the evolution processes affecting these star forming galaxies.
In this talk, I will present a spatially...
Recent studies have revealed the existence of particularly massive galaxies within the first Gyr after the Big Bang. These findings push the limits of galaxy evolution models, but our understanding of the formation of such galaxies is limited due to a lack of sub-kpc resolution observations of bright, spectroscopically-confirmed targets.
The REBELS ALMA large program have observed [CII]...
How galaxies replenish their gas supply in order to sustain star formation, is a research topic of many of the new and upcoming neutral atomic hydrogen (HI) surveys on the SKA precursor instruments.
I present recent deep HI observations of NGC 5068, an isolated nearby star-forming galaxy observed by MeerKAT as part of the MHONGOOSE survey. This survey is the deepest HI survey of nearby...
Understanding how supermassive black holes and their host galaxies co-evolve in the universe is an unsolved problem. In a classical “unified” model for active galactic nuclei (AGN), observers can detect unobscured (Type-1) AGNs,with broad emission lines and continuum, or obscured (Type-2) AGNs, with only narrow emission lines. Type-2 AGNs have been readily identified at low redshift (z<1)....
Feedback from radio AGN has been observed in the form of jet driven gas outflows, which can affect the host galaxy’s evolution. Radio AGN are also known to have a life-cycle of activity. However it is still not completely clear how feedback evolves with the AGN life-cycle. In the first part of my talk, I will discuss our results from a study to investigate this with a sample of uniformly...
X-ray emission from young supernova remnants (SNRs) is characterized by non-thermal radiation and is usually interpreted as synchrotron process. This type of emission is detected in regions close to the shock front and it is explained with the the diffusive shock acceleration (DSA) theory, which requires high magnetic turbulence. However, the current spectral models used to fit the data...
Since the first detection by LIGO in 2015, gravitational-wave detectors observe mergers of black holes which formed in the low-metallicity, high-redshift Universe. A main uncertainty in our understanding of these mergers is the evolution of the progenitor stars of these black holes – stars more massive than ~20 solar masses. WC/WO stars are hot, post main-sequence stars with powerful winds...
Understanding and modelling the complex state of the Sun-solar wind-heliosphere system, requires a comprehensive set of multiwavelength observations. LOFAR has unique capabilities in the radio domain. Some examples of these include: a) the ability to take high-resolution solar dynamic spectra and radio images of the Sun; b) observing the ionospheric scintillation and the iterplanetary...
The serendipitous appearances of Near-Earth Objects (NEOs) in a subset of the millions of archival exposures of optical and near-infrared astronomical imaging surveys can improve our knowledge of the orbits and compositions of NEOs. We show how the data processing and data mining of such imaging archives can be exploited to identify new and known NEOs, leading to a re-assessment of the impact...
