The gravitational collapse of massive stars can lead to extreme stellar explosions when both fast rotation and strong magnetic fields are present during the onset of the supernova. A detailed understanding of how magnetic fields extract angular momentum from the central proto-neutron star is paramount to produce quantitative predictions with respect to not only the explosion dynamics, but also...
Simulations of astrophysical systems where neutrinos play a significant role, like core-collapse supernovae, would ideally solve the neutrino transport equation fully, i.e. solve the full Boltzmann equation. Because of its very high computational cost (6+1D), simulations generally rely on approximations of the equation that are more affordable. It is however difficult to estimate what is lost...
Collective neutrino oscillation induced by neutrino self-interaction has been brought great attention in theoretical CCSN modeling.
Especially fast flavor conversion (FFC), which is caused by angular crossings in momentum space, is expected to affect CCSN dynamics.
However, including FFC effects into CCSN simulation is challenging because (1) FFC depends on momentum space angle distribution,...
The low-frequency contribution to gravitational wave signals from core-collapse supernovae has often been overlooked due to the rapid increase in the LIGO noise floor at 10 Hz, but recent studies have illuminated the rich content of core-collapse supernova gravitational wave emission in this frequency range and the exciting prospects for its detection. Here, I will present a brief review of...
The yet-to-be-detected gravitational wave signal from core-collapse supernovae is expected to be dominated by oscillation modes of the newly born proto-neutron star (PNS). I am going to present a new general relativistic framework for computing the oscillation modes of a PNS, including, for the first time, an accretion flow and a surrounding stalled accretion shock. The oscillations can be...
Galactic (or near Galactic) core-collapse supernova (CCSN) is currently one of the most anticipated astrophysical events of the century. CCSN are multimessenger astronomy events that work as exceptional laboratories enclosing different carriers of physical information, neutrinos, photons, and gravitational waves (GWs) all coexisting in a single event. The CCSN GW signals are characterized by a...
Core-collapse supernovae are exploding massive stars and the next Galactic event will be one of the most interesting astronomical events of the century. After the collapse of a star's core, a so-called proto-neutron star (PNS) is formed, heating the star from the inside and creating a shock wave. It is believed that the majority of the gravitational-wave (GW) emission comes from PNS. The GW...
The astrophysical origin of heavy elements in the universe synthesised through the rapid neutron capture process (r-process) remains an open question, with several compact object environments such as neutron star mergers, collapsars, and magnetorotational supernovae proposed as potential sites. Systems involving accreting black holes and surrounding disks are particularly promising, as they...
Core-collapse supernovae are among the most energetic explosions in the universe. Their evolution is shaped by hydrodynamics, neutrino transport, and magnetic fields at work in the first seconds after collapse. We investigate these processes through 3D simulations of an extremely compact 39 Msun progenitor using the FLASH M1 magnetohydrodynamics code. Our study explores three models – a...
Gamma-ray bursts are one of the most energetic phenomena in the Universe. The collapsar model is the most widely accepted model for explaining long gamma-ray bursts. This model proposes that cores of massive stars with sufficient angular momentum collapse to black holes, while the stellar envelope starts to fall onto the newly born object. We performed three-dimensional GRMHD simulations of...
The generation of synthetic gravitational wave signals from core-collapse supernovae can provide a valuable tool for data augmentation in machine learning pipelines, especially for the training of detection and classification algorithms. These waveforms encode critical astrophysical information, such as the ratio of rotational kinetic to gravitational potential energy at bounce, pre-collapse...
Detection of gravitational wave emissions from a nearby core-collapse supernova explosion would mark the next milestone in gravitational wave astrophysics and multi-messenger astronomy, although the nature of the supernova explosion engine remains elusive. One possible engine is through the magneto-rotational mechanism, which may power extreme phenomena such as hypernovae and long gamma-ray...
Multi-messenger signals of gravitational waves and neutrinos from supernovae carry information about properties of supernova cores, which cannot be directly observed with electromagnetic waves. To maximize impacts of future detection of these multi-messenger signals, it is important to understand the relationship between the characteristics of the multi-messenger signals and the properties of...
High-energy astrophysical events, such as core-collapse supernovae and binary neutron-star mergers, are promising sources of detectable gravitational waves. In these extremely dense environments, neutrino transport plays a crucial role in shaping the dynamics and observables. However, most numerical models to date employ classical neutrino transport, neglecting quantum kinetic effects. In...
Calibration of gravitational wave detectors is an intricate and critical process, with amplitude and phase uncertainties typically at the percent level. These calibration uncertainties, which vary with frequency, are routinely incorporated into compact binary coalescence parameter estimation. However, their influence on burst searches and supernova parameter estimation is less explored. In...
In this study, we formulate and describe a method for estimating parameters for rotating core-collapse supernovae, using the gravitational wave core bounce phase as a basis.
We introduce an analytical framework for the core bounce component that is determined by the ratio β, which characterizes the relationship between rotational kinetic energy and potential energy, alongside a...
Core collapse supernovae (CCSNe) are the explosive deaths of massive stars, followed by the formation of a proto-neutron star. Gravitational wave signals from these extremely compact objects can simultaneously inform macroscopic and microscopic physics, ranging from modeling what powers supernovae to constraining the nuclear equation of state. As the inner core of the collapsing star becomes...
The traditional CCSN search method relies on coherence information between multiple gravitational wave detectors to identify candidate events. This requirement reduces the effective lifetime of the search, as it excludes periods when only a single detector is operational. To address this limitation, we present a machine learning (ML)-based framework designed to enable single-detector detection...
Core-collapse supernova in the Milky Way will be one of the most interesting astronomical events of the century. As the massive core suddenly collapses a huge number of neutrinos is produced. Around a hundred milliseconds after the collapse the asymmetry of a supernova evolves through a Ledoux convection. It is believed that it marks the beginning of an efficient emission of gravitational...
Core-collapse supernova (CCSN) marks the final stage of massive stars ($M>8M_{\odot}$) entering in a violent and energetic explosion process that might be considered as one of the most anticipated astrophysical events of the century. Following the collapse of the star's core, a dense proto-neutron star (PNS) forms. Within this PNS, complex dynamics involving convection instabilities,...
Core-collapse supernovae (CCSNe) are exploding massive stars and the next Galactic event will be one of the most interesting astronomical events of the century. With the advent of the three-dimensional CCSN simulations, the number of methods to infer physical information from a gravitational wave (GW) discovery grew significantly. For example, the proto-neutron star evolution and deciphering...
Electromagnetic observations of core collapse supernovae (CCSNe) provide a wealth of information about the explosion mechanisms and trigger the searches for the possible associated gravitational wave emission.
CCSNe with distances that are less than approximatively 30 Mpc are candidate targets for the LIGO/Virgo/KAGRA searches during the ongoing observing run. Supernovae are routinely...
During a core-collapse supernova, a strong reverse shock forms at the interface between the hydrogen envelope and the helium core, slowing the ejecta and driving some material back onto the newborn compact object. Conventional Eulerian simulations usually place an inner radial boundary, yet when the reverse shock reaches this boundary, it can generate a reflecting wave that hides the true...
I will present recent results of the CFT astrophysics group on the theoretical modeling of long Gamma Ray Bursts resulting from collapsars. We focus on the massive star collapse mechanisms as well as the jet breakout and its interactions with dynamically ejected envelope.
We also probe the crucial role of self-gravity and magnetic field play
in determining the newly formed black hole...
GRBs from collapsars have been studied by imposing jets at intermediate scales beyond the iron core region while exploring a wide range of parameters, such as luminosity and central engine duration. However, these conditions should be validated by studying jets launched directly from the central engine to show a global picture of the jet propagation inside and outside of the progenitor star....
Core-collapse supernovae stand out as key multi-messenger candidates to probe the internal dynamics of stellar supernova explosions with gravitational waves, light, and neutrinos. These complex processes have motivated multiple efforts to simulate core-collapse supernovae and predict the observational signatures with different simulation and progenitor parameters. In order to develop a...
Gravitational-wave (GW) emissions from core-collapse supernovae (CCSNe) provide insights into the internal processes leading up to their explosions. Theory predicts that CCSN explosions are driven by hydrodynamical instabilities like the standing accretion shock instability or neutrino-driven convection, and simulations show that these mechanisms emit GWs at low frequencies ($\lesssim 250 $...
A supernova, the violent death of a massive star, is a promising source for multimessenger astronomy, involving electromagnetic waves, neutrinos, and gravitational waves (GWs). In this talk, I will discuss the methods and challenges of GW detection from core-collapse supernovae
Till date ~200 compact binaries have been detected with the current gravitational wave (GW) detectors. This number is expected to increase by orders of magnitude in the 3G detector era.
In Singh et al 2020 and 2024, we have shown that with just ET as a single instrument, the mass distributions and the merger rate densities of compact binaries will have much better constraints.
The...
One of the major uncertainties in core-collapse supernova phenomenology lies in the equation of state at high densities. Of particular interest is the possibility of a first-order phase transition from hadronic matter to deconfined quark matter—a topic that has recently gained attention due to its potential observational signatures in neutrinos and gravitational waves [1–7]. In this talk, I...
A novel functional form for fitting neutrino luminosities from
core-collapse supernovae was recently proposed by Lucente et al. (2024),
capturing the effects of convection inside the proto-neutron star (PNS)
through a power-law temporal decay. While this model accurately
describes the cooling phase, it does not account for the neutrino flux
during, approximately, the first second, which...
In this work we use an analytical model that fits the Core-Bounce phase of Core Collapse Supernovae and it depends upon one physical parameter (the rotational rate) and two more phenomenological ones, which adjust the waveform to a Richers catalog of 2D axisymmetric simulations. Three different scenarios were considered in this work. The first one aims to test Markov Chain – Monte Carlo...
Gravitational waveforms arising from core-collapse supernova are yet to be observed by the existing detectors. Simulating GW waveforms for CCSN consumes a considerable number of resources. In this work we have employed the advantage of a machine learning technique, specifically conditional variational autoencoder to generate the waveforms of the CCSN. For training, publicly available...
Core-collapse supernovae are the most promising astrophysical sources of burst gravitational waves for current and next-generation interferometric detectors. In the post-bounce phase of CCSNe, the Standing Accretion Shock Instability (SASI) plays a crucial role in the explosion mechanism, generating distinctive, quasi-periodic gravitational wave signatures. Accurate detection and...
Core-collapse supernovae (CCSN) are one of the most violent and energetic astronomical processes in the Universe. The next Galactic supernova can offer us an exceptional opportunity to delve deep into the explosion mechanism through gravitational waves (GWs) emission. Theoretical developments in CCSN modeling hint at the variation of GW signature with respect to the source angle orientation....
Core-collapse supernovae (CCSNe) are exploding massive stars and the next Galactic event will be one of the most interesting astronomical events of the century. While these events are violent, the gravitational field is still relatively weak. Unlike the compact binaries with strong field regime where gravitational waveforms are given as spherical-harmonic modes in the Newman-Person formalism....
Core-collapse supernovae (CCSNe) are exploding massive stars and the next Galactic event will be one of the most interesting astronomical events of the century. If the nearby CCSN will be strong enough and the light won't be obscured by the Galactic dust then it may be visible in the sky. If gravitational waves are detected, we will be able to even listen to this explosion. The sounds of...
The use of Artificial Intelligence (AI), Machine Learning (ML), and High-Performance Computing (HPC) is playing an increasingly important role in advancing how we detect gravitational waves (GW).GW signals from core-collapse supernovae (CCSN) are still undetected. These signals are inherently weak, unmodeled and often masked by environmental and instrumental noise, presenting significant...
The goal of the project is to investigate the potential of different distributional methods in the detection of Core-Collapse supernova gravitational waves (GW) for quiet signals that would have been previously missed. To date, no supernova GW detections have been made. We use coherent WaveBurst to look at the loudest events in a span of time and form a metric for each event, which we collect...
Gravitational waves offer a direct way to probe the explosion mechanism of core-collapse supernovae and proto-neutron star turbulence. By combining state-of-the-art 3D-MHD convection simulations with physics-informed scaling laws, we generate synthetic GW spectrograms up to 7 seconds post-bounce—much longer than what is typically achieved with global core-collapse models. We examine how the GW...
Certain features of the gravitational wave spectrogram from core-collapse supernovae are the imprint of excited oscillation modes of the dense proto-compact star, excited by various manifestations of asymmetric fluid motion. One of the most robust signal components arises from a quadrupolar f/g-mode whose frequency increases from a few hundred Hz to above 1 kHz. In addition, another distinct...
Core-collapse supernovae (CCSNe) are among the most energetic astrophysical phenomena. The next Galactic CCSN will be a landmark event and Gravitational Waves (GWs) from this CCSN will offer an unique opportunity to study the explosion dynamics in detail. In this poster, we will present the development of a method for the model-independent Coherent WaveBurst (cWB) algorithm to estimate GW...
Gravitational waves from core-collapse supernovae remain one of the most promising, but as yet undetected, sources for LIGO, Virgo, and KAGRA. Confidently reconstructing a supernova waveform, or inferring key signal properties, could provide critical insight into the explosion mechanism. This task remains challenging however due to the wide range of possible signal morphologies. In this talk,...
After decades of intense research, the "neutrino-driven explosion mechanism" has meanwhile been established as the most promising and widely accepted paradigm for the majority of core-collapse supernovae (CCSNe). Nevertheless, the question remained whether the neutrino-driven mechanism can explain the characteristic properties of observed supernovae, such as explosion energies, nucleosynthesis...
