papers

Publications (52)

astro-ph.HE2026

High-energy neutrino emission from the Milky Way

R. Abbasi, M. Ackermann, J. Adams +440

The Milky Way hosts astrophysical objects that accelerate cosmic rays to energies beyond the reach of terrestrial particle accelerators. It remains a longstanding goal to locate th…

gr-qc2026

All-sky Searches for Continuous Gravitational Waves from Isolated Neutron Stars in the Data from the First Part of the Fourth LIGO-Virgo-KAGRA Observing Run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1826

We present results from an all-sky search for continuous gravitational waves, using three different methods applied to the first eight months of LIGO data from the fourth LIGO-Virg…

gr-qc2025

Open Data from LIGO, Virgo, and KAGRA through the First Part of the Fourth Observing Run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1768

LIGO, Virgo, and KAGRA form a network of gravitational-wave observatories. Data and analysis results from this network are made publicly available through the Gravitational Wave Op…

astro-ph.HE2025

Characterization of the Three-Flavor Composition of Cosmic Neutrinos with IceCube

R. Abbasi, M. Ackermann, J. Adams +429

Neutrinos oscillate over cosmic distances. Using 11.4 years of IceCube data, the flavor composition of the all-sky neutrino flux from 5\,TeV--10\,PeV is studied. We report the firs…

astro-ph.HE2025

Constraints on the Correlation of IceCube Neutrinos with Tracers of Large-Scale Structure

R. Abbasi, M. Ackermann, J. Adams +430

The IceCube Neutrino Observatory has observed extragalactic astrophysical neutrinos with an apparently isotropic distribution. Only a small fraction of the observed astrophysical n…

gr-qc2026

GWTC-4.0: Tests of General Relativity. II. Parameterized Tests

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1785

In this second of three papers on tests of general relativity (GR) applied to the compact binary coalescence signals in the 4th Gravitational-Wave Transient Catalog (GWTC-4.0), we…

gr-qc2025

Directional Search for Persistent Gravitational Waves: Results from the First Part of LIGO-Virgo-KAGRA's Fourth Observing Run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1765

The angular distribution of gravitational-wave power from persistent sources may exhibit anisotropies arising from the large-scale structure of the Universe. This motivates directi…

astro-ph.CO2025

Direct multi-model dark-matter search with gravitational-wave interferometers using data from the first part of the fourth LIGO-Virgo-KAGRA observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1767

Gravitational-wave detectors can probe the existence of dark matter with exquisite sensitivity. Here, we perform a search for three kinds of dark matter -- dilatons (spin-0), dark…

astro-ph.HE2025

GW231123: a Binary Black Hole Merger with Total Mass 190-265

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1771

On 2023 November 23 the two LIGO observatories both detected GW231123, a gravitational-wave signal consistent with the merger of two black holes with masses $137^{+23}_{-18}\, M_\o…

astro-ph.HE2026

Improved measurements of the TeV-PeV extragalactic neutrino spectrum from joint analyses of IceCube tracks and cascades

R. Abbasi, M. Ackermann, J. Adams +424

The IceCube South Pole Neutrino Observatory has discovered the presence of a diffuse astrophysical neutrino flux at energies of TeV and beyond using neutrino induced muon tracks an…

astro-ph.HE2026

Evidence for a Spectral Break or Curvature in the Spectrum of Astrophysical Neutrinos from 5 TeV--10 PeV

R. Abbasi, M. Ackermann, J. Adams +424

We report improved measurements of the all flavor astrophysical neutrino spectrum with IceCube by combining complementary neutrino samples in two independent analyses. Both analyse…

gr-qc2026

Directed searches for gravitational waves from ultralight vector boson clouds around merger remnant and galactic black holes during the first part of the fourth LIGO-Virgo-KAGRA observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1769

We present the first directed searches for long-transient and continuous gravitational waves from ultralight vector boson clouds around known black holes (BHs). We use LIGO data fr…

gr-qc2026

GWTC-4.0: Updating the Gravitational-Wave Transient Catalog with Observations from the First Part of the Fourth LIGO-Virgo-KAGRA Observing Run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1786

Version 4.0 of the Gravitational-Wave Transient Catalog (GWTC-4.0) adds new candidates detected by the LIGO, Virgo, and KAGRA observatories through the first part of the fourth obs…

hep-ex2026

Sensitivity Projections for Low-Mass Dark Matter Annihilation with the IceCube Upgrade

R. Abbasi, M. Ackermann, J. Adams +412

The IceCube Upgrade, an extension designed to enhance the IceCube Neutrino Observatory's detection of neutrinos with energies between 1 GeV and 500 GeV, will markedly improve IceCu…

astro-ph.CO2025

GWTC-4.0: Constraints on the Cosmic Expansion Rate and Modified Gravitational-wave Propagation

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1772

We analyze data from 142 of the 218 gravitational-wave (GW) sources in the fourth LIGO-Virgo-KAGRA Collaboration (LVK) Gravitational-Wave Transient Catalog (GWTC-4.0) to estimate t…

gr-qc2026

GWTC-4.0: Tests of General Relativity. III. Tests of the Remnants

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1779

This is the third paper of the set recording the results of the suite of tests of general relativity (GR) performed on the signals from the fourth Gravitational-Wave Transient Cata…

astro-ph.HE2026

Evidence for neutrino emission from X-ray Bright Seyfert Galaxies in the Southern Hemisphere using Enhanced Starting Track Events with IceCube

R. Abbasi, M. Ackermann, J. Adams +428

IceCube recently reported the observation of TeV neutrinos from the nearby Seyfert galaxy NGC~1068, and the corresponding neutrino flux is significantly higher than the upper limit…

hep-ex2026

Identification and Denoising of Radio Signals from Cosmic-Ray Air Showers using Convolutional Neural Networks

R. Abbasi, M. Ackermann, J. Adams +426

Radio pulses generated by cosmic-ray air showers can be used to reconstruct key properties like the energy and depth of the electromagnetic component of cosmic-ray air showers. Rad…

physics.ins-det2026

WavePID: Low-energy flavor identification using single-PMT time series in IceCube

R. Abbasi, M. Ackermann, J. Adams +416

The IceCube Neutrino Observatory, a cubic-kilometer detector at the South Pole, identifies neutrino flavor through event morphology. Sparse photon detection makes this classificati…

astro-ph.HE2026

High-Energy Neutrino Tomography of the Earth's Interior with IceCube

The IceCube Collaboration, R. Abbasi, M. Ackermann +417

The Earth's interior reflects its geological evolution, from accretion to present-day dynamics. Its structure drives the geodynamo in the outer core, generating the magnetic field…

gr-qc2025

Cosmological and High Energy Physics implications from gravitational-wave background searches in LIGO-Virgo-KAGRA's O1-O4a runs

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1769

We search for gravitational-wave background signals produced by various early Universe processes in the Advanced LIGO O4a dataset, combined with the data from the earlier O1, O2, a…

gr-qc2025

GW250114: testing Hawking's area law and the Kerr nature of black holes

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1785

The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. The signal was emitted by the coalescence o…

astro-ph.HE2025

The IceCube Collaboration -- Contributions to the 39th International Cosmic Ray Conference (ICRC2025)

R. Abbasi, M. Ackermann, J. Adams +426

The IceCube Observatory at the South Pole has been operating in its full configuration since May 2011 with a duty cycle of about 99%. Its main component consists of a cubic-kilomet…

gr-qc2026

Constraints on gravitational waves from the 2024 Vela pulsar glitch

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1774

Among known neutron stars, the Vela pulsar is one of the best targets for gravitational-wave searches. It is also one of the most prolific in terms of glitches, sudden frequency ch…

astro-ph.HE2026

IceCube Second Track Data Release IceTracks-DR2: Data from 2008-2022 for Neutrino Source Searches

R. Abbasi, M. Ackermann, J. Adams +412

We present IceCube's latest release of muon track data for neutrino point-source searches, extending the previously published 10-year dataset to cover 14 years of observations (Apr…

astro-ph.HE2026

Search for GeV-scale Dark Matter from the Galactic Center with IceCube-DeepCore

The IceCube Collaboration, R. Abbasi, M. Ackermann +431

Models describing dark matter as a novel particle often predict that its annihilation or decay into Standard Model particles could produce a detectable neutrino flux in regions of…

gr-qc2026

GWTC-4.0: Tests of General Relativity. I. Overview and General Tests

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1781

The worldwide LIGO-Virgo-KAGRA network of gravitational-wave (GW) detectors continues to increase in sensitivity, thus increasing the quantity and quality of the detected GW signal…

astro-ph.HE2026

Searches for Binary Mergers with Sub-solar Mass Components in Data from the First Part of LIGO--Virgo--KAGRA's Fourth Observing Run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1834

We report on a gravitational wave search for compact binary coalescences involving at least one component with mass between to , and ratio of component m…

gr-qc2025

Upper Limits on the Isotropic Gravitational-Wave Background from the first part of LIGO, Virgo, and KAGRA's fourth Observing Run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1773

We present results from the search for an isotropic gravitational-wave background using Advanced LIGO and Advanced Virgo data from O1 through O4a, the first part of the fourth obse…

astro-ph.IM2025

The LED calibration systems for the mDOM and D-Egg sensor modules of the IceCube Upgrade

R. Abbasi, M. Ackermann, J. Adams +432

The IceCube Neutrino Observatory, instrumenting about 1 km of deep, glacial ice at the geographic South Pole, is due to be enhanced with the IceCube Upgrade. The IceCube Upgrad…

gr-qc2025

All-sky search for long-duration gravitational-wave transients in the first part of the fourth LIGO-Virgo-KAGRA Observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1772

We present an all-sky search for long-duration gravitational waves (GWs) from the first part of the LIGO-Virgo-KAGRA fourth observing run (O4), called O4a and comprising data taken…

astro-ph.HE2026

Deep Search for Joint Sources of Gravitational Waves and High-Energy Neutrinos with IceCube During the Third Observing Run of LIGO and Virgo

The IceCube Collaboration, R. Abbasi, M. Ackermann +2209

The discovery of joint sources of high-energy neutrinos and gravitational waves has been a primary target for the LIGO, Virgo, KAGRA, and IceCube observatories. The joint detection…

astro-ph.HE2025

Limits on GeV-scale WIMP Annihilation in Dwarf Spheroidals with IceCube DeepCore

R. Abbasi, M. Ackermann, J. Adams +428

Dark matter is approximately five times more abundant than baryonic matter in the universe, but its physical nature continues to elude physicists. One potential candidate for dark…

gr-qc2026

GWTC-4.0: Searches for Gravitational-Wave Lensing Signatures

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1766

Gravitational waves can be gravitationally lensed by massive objects along their path. Depending on the lens mass and the lens--source geometry, this can lead to the observation of…

gr-qc2026

GW230814: investigation of a loud gravitational-wave signal observed with a single detector

The LIGO Scientific Collaboration, The Virgo Collaboration, The Kagra Collaboration +1783

GW230814, detected by the LIGO Livingston observatory with a signal-to-noise ratio of 42.4, represents the loudest gravitational-wave signal in the GWTC-4.0 catalog. Its source is…

gr-qc2025

Search for planetary-mass ultra-compact binaries using data from the first part of the LIGO--Virgo--KAGRA fourth observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1802

We present a search for gravitational waves from inspiraling, planetary-mass ultra-compact binaries using data from the first part of the fourth observing run of LIGO, Virgo and KA…

astro-ph.HE2025

All-sky neutrino point-source search with IceCube combined track and cascade data

R. Abbasi, M. Ackermann, J. Adams +424

Despite extensive efforts, discovery of high-energy astrophysical neutrino sources remains elusive. We present an event-level simultaneous maximum likelihood analysis of tracks and…

hep-ex2025

Limiting the Parameter Space for Unstable eV-scale Neutrinos Using IceCube Data

R. Abbasi, M. Ackermann, J. Adams +422

This Letter extends a recent IceCube sterile neutrino search to include unstable sterile neutrinos within the context of a model termed 3+1+Decay, which expands upon the 3+1 model…

hep-ex2026

Neural posterior estimation of the neutrino direction in IceCube using transformer-encoded normalizing flows on the sphere

R. Abbasi, M. Ackermann, J. Adams +411

IceCube is a cubic-kilometer-scale neutrino detector located at the geographic South Pole. A precise directional reconstruction of IceCube neutrinos is vital for associations with…

astro-ph.HE2025

Constraining the Prompt Atmospheric Neutrino Flux Combining IceCube's Cascade and Track Samples

R. Abbasi, M. Ackermann, J. Adams +428

The IceCube Neutrino Observatory has observed a diffuse flux of high-energy astrophysical neutrinos for more than a decade. A relevant background to the astrophysical flux is promp…

gr-qc2026

Narrowband searches for continuous gravitational waves from known pulsars in the first two parts of the fourth LIGO--Virgo--KAGRA observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1853

Rotating non-axisymmetric neutron stars (NSs) are promising sources for continuous gravitational waves (CWs). Such CWs can, if detected, inform us about the internal structure and…

astro-ph.HE2026

Sub-Torque-Balance Upper Limits on Continuous Gravitational Waves from Scorpius X-1

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1836

We present the results of a search for continuous gravitational waves from the low-mass X-ray binary Scorpius X-1 using LIGO data from the first part of the fourth LIGO-Virgo-KAGRA…

astro-ph.IM2026

Advanced Virgo Plus for O5 -- Design Report Overview

F. Acernese, A. Agapito, D. Agarwal +578

This document presents an overview of the design, implementation, and expected performance of the Advanced Virgo Plus (AdV+) upgrades in view of the O5 observing run. Following the…

gr-qc2026

Searches for Continuous Gravitational Waves from Supernova Remnants in the first part of the LIGO-Virgo-KAGRA Fourth Observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1764

We present results from directed searches for continuous gravitational waves from a sample of 15 nearby supernova remnants, likely hosting young neutron star candidates, using data…

hep-ex2025

Search for High-Energy Neutrinos From the Sun Using Ten Years of IceCube Data

R. Abbasi, M. Ackermann, J. Adams +424

In this Letter, we present the results of a search for high-energy neutrinos produced by the annihilation of dark matter particles trapped in the Sun. Using 9.3 and 10.4 years of d…

astro-ph.HE2026

IceCube Real-time Searches for High-energy Neutrinos Coincident with LIGO/Virgo/KAGRA Gravitational-Wave Alerts in O4a

The IceCube Collaboration, R. Abbasi, M. Ackermann +418

Gravitational-wave events from mergers of compact objects are a predicted source of high-energy neutrinos. Using data from the IceCube Neutrino Observatory, we search for neutrinos…

astro-ph.HE2025

Prompt Searches for Very-High-Energy γ-Ray Counterparts to IceCube Astrophysical Neutrino Alerts

J. Abhir, A. Biland, K. Brand +817

The search for sources of high-energy astrophysical neutrinos can be significantly advanced through a multi-messenger approach, which seeks to detect the gamma rays that accompany…

astro-ph.HE2025

GW241011 and GW241110: Exploring Binary Formation and Fundamental Physics with Asymmetric, High-Spin Black Hole Coalescence

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1783

We report the observation of gravitational waves from two binary black hole coalescences during the fourth observing run of the LIGO--Virgo--KAGRA detector network, GW241011 and GW…

gr-qc2025

All-sky search for continuous gravitational-wave signals from unknown neutron stars in binary systems in the first part of the fourth LIGO-Virgo-KAGRA observing run

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1765

We present the results of a blind all-sky search for continuous gravitational-wave signals from neutron stars in binary systems using data from the first part of the fourth observi…

astro-ph.HE2026

Evidence for Neutrino Emission from X-Ray-bright Active Galactic Nuclei with IceCube

R. Abbasi, M. Ackermann, J. Adams +429

Recently, IceCube reported neutrino emission from the Seyfert galaxy NGC 1068. Using 13.1 years of IceCube data, we present a follow-up search for neutrino sources in the northern…

hep-ex2026

Estimating the sensitivity of the IceCube Upgrade to probe the interior of the Earth using atmospheric neutrino oscillations

The IceCube Collaboration, R. Abbasi, M. Ackermann +421

The IceCube Upgrade is a densely instrumented central region of the IceCube Neutrino Observatory, deployed during the 2025-26 polar season. It will reduce the detector's energy thr…

gr-qc2026

GW240925 and GW250207: Astrophysical Calibration of Gravitational-wave Detectors

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration +1839

GW240925 and GW250207 are two loud gravitational-wave signals from binary black hole coalescences observed with network signal-to-noise ratios and , respectively…