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Tytuł:
All-sky search for short gravitational-wave bursts in the first part of the fourth LIGO-Virgo-KAGRA observing run
Autorzy:
Kubisz, Jerzy
Współwytwórcy:
Współautorami artykułu są członkowie LIGO Scientific Collaboration Virgo Collaboration, KAGRA Collaboration w liczbie 1763
Opis:
We present a search for short-duration gravitational-wave transients in data from the first eight months of Advanced LIGO-Virgo-KAGRA’s fourth observing run, denoted O4a. We use four analyses which are sensitive to a wide range of potential signals lasting up to a few seconds in the 16–4096 Hz band. Excluding binary black hole merger candidates that were already identified by low-latency analyses, we find no statistically significant evidence for other gravitational-wave transients. We measure the sensitivity of the search for representative signals, including sine-Gaussians, Gaussian pulses, and white-noise bursts with different frequencies and durations, adopting a false alarm rate of 1 per 100 years as detection threshold. Depending on signal type, we find improvements over previous searches by factors of 2 to 10 in terms of sensitivity to strain amplitude and of 90% confidence upper limit on the rate density of sources. We also evaluate a variety of core-collapse supernova models and find that, for some models, the search could have detected gravitational waves from stellar core-collapse throughout the Milky Way. Finally, we consider neutron star f-modes associated with pulsar glitches and find that, assuming a source similar to the Vela Pulsar, the search could have detected a gravitational-wave signal from a glitch with fractional frequency change as small as ∼ 2 to 6 $\times$ 10$^{-5}$ depending on the neutron star mass.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
GW241011 and GW241110 : exploring binary formation and fundamental physics with asymmetric, high-spin black hole coalescences
Autorzy:
Kubisz, Jerzy
Współwytwórcy:
Współautorami artykułu są członkowie LIGO Scientific Collaboration, Virgo Collaboration, KAGRA Collaboration w liczbie 1782
Opis:
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 GW241110. The sources of these two signals are characterized by rapid and precisely measured primary spins, nonnegligible spin–orbit misalignment, and unequal mass ratios between their constituent black holes. These properties are characteristic of binaries in which the more massive object was itself formed from a previous binary black hole merger and suggest that the sources of GW241011 and GW241110 may have formed in dense stellar environments in which repeated mergers can take place. As the third-loudest gravitational-wave event published to date, with a median network signal-to-noise ratio of 36.0, GW241011 furthermore yields stringent constraints on the Kerr nature of black holes, the multipolar structure of gravitational-wave generation, and the existence of ultralight bosons within the mass range 10$^{−13}$–10$^{−12}$ eV.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
Search for gravitational waves emitted from SN 2023ixf
Autorzy:
Kubisz, Jerzy
Współwytwórcy:
Współautorami artykułu są członkowie LIGO Scientific Collaboration, Virgo Collaboration, KAGRA Collaboration w liczbie 1778
Opis:
We present the results of a search for gravitational-wave transients associated with core-collapse supernova SN 2023ixf, which was observed in the galaxy Messier 101 via optical emission on 2023 May 19, during the LIGO–Virgo–KAGRA 15th Engineering Run. We define a five-day on-source window during which an accompanying gravitational-wave signal may have occurred. No gravitational waves have been identified in data when at least two gravitational-wave observatories were operating, which covered ∼14% of this five-day window. We report the search detection efficiency for various possible gravitational-wave emission models. Considering the distance to M101 (6.7 Mpc), we derive constraints on the gravitational-wave emission mechanism of core-collapse supernovae across a broad frequency spectrum, ranging from 50 Hz to 2 kHz, where we assume the gravitational-wave emission occurred when coincident data are available in the on-source window. Considering an ellipsoid model for a rotating proto-neutron star, our search is sensitive to gravitational-wave energy 1 $\times$ 10$^{−4}$ M$_{⊙}$c$^{2}$ and luminosity 2.6 $\times$ 10$^{−4}$ M$_{⊙}$c$^{2}$ s$^{−1}$ for a source emitting at 82 Hz. These constraints are around an order of magnitude more stringent than those obtained so far with gravitational-wave data. The constraint on the ellipticity of the proto-neutron star that is formed is as low as 1.08, at frequencies above 1200 Hz, surpassing past results.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
Observation of gravitational waves from the coalescence of a 2.5–4.5 M$_{\bigodot }$ compact object and a neutron star
Autorzy:
Kubisz, Jerzy
Współwytwórcy:
Współautorami artykułu są członkowie LIGO Scientific Collaboration, Virgo Collaboration i KAGRA Collaboration w liczbie 1794
Opis:
We report the observation of a coalescing compact binary with component masses 2.5–4.5 M$_{\bigodot }$ and 1.2–2.0 M$_{\bigodot }$ (all measurements quoted at the 90% credible level). The gravitational-wave signal GW230529_181500 was observed during the fourth observing run of the LIGO–Virgo–KAGRA detector network on 2023 May 29 by the LIGO Livingston observatory. The primary component of the source has a mass less than 5 M$_{\bigodot }$ at 99% credibility. We cannot definitively determine from gravitational-wave data alone whether either component of the source is a neutron star or a black hole. However, given existing estimates of the maximum neutron star mass, we find the most probable interpretation of the source to be the coalescence of a neutron star with a black hole that has a mass between the most massive neutron stars and the least massive black holes observed in the Galaxy. We provisionally estimate a merger rate density of 55$^{+127}_{-47}$ GPC$^{-3}$yr$^{-1}$ for compact binary coalescences with properties similar to the source of GW230529_181500; assuming that the source is a neutron star–black hole merger, GW230529_181500-like sources may make up the majority of neutron star–black hole coalescences. The discovery of this system implies an increase in the expected rate of neutron star–black hole mergers with electromagnetic counterparts and provides further evidence for compact objects existing within the purported lower mass gap.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
A search using GEO600 for gravitational waves coincident with fast radio bursts from SGR 1935+2154
Autorzy:
Kubisz, Jerzy
Współwytwórcy:
Współautorami artykułu są członkowie LIGO Scientific Collaboration, Virgo Collaboration i KAGRA Collaboration w liczbie 1779
Opis:
The magnetar SGR 1935+2154 is the only known Galactic source of fast radio bursts (FRBs). FRBs from SGR 1935+2154 were first detected by the Canadian Hydrogen Intensity Mapping Experiment (CHIME)/FRB and the Survey for Transient Astronomical Radio Emission 2 in 2020 April, after the conclusion of the LIGO, Virgo, and KAGRA Collaborations' O3 observing run. Here, we analyze four periods of gravitational wave (GW) data from the GEO600 detector coincident with four periods of FRB activity detected by CHIME/FRB, as well as X-ray glitches and X-ray bursts detected by NICER and NuSTAR close to the time of one of the FRBs. We do not detect any significant GW emission from any of the events. Instead, using a short-duration GW search (for bursts ≤1 s) we derive 50% (90%) upper limits of 10$^{48}$ (10$^{49}$) erg for GWs at 300 Hz and 10$^{49}$ (10$^{50}$) erg at 2 kHz, and constrain the GW-to-radio energy ratio to ≤ 10$^{14}$−10$^{16}$. We also derive upper limits from a long-duration search for bursts with durations between 1 and 10 s. These represent the strictest upper limits on concurrent GW emission from FRBs
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł
Tytuł:
Test of CPT symmetry with positronium at the J-PET detector
Autorzy:
Czerwiński, Eryk
Współwytwórcy:
J-PET Collaboration
Wydawca:
World Scientific Publishing
Opis:
The Jagiellonian Positron Emission Tomograph (J-PET) is the first tomograph built from plastic scintillators capable to test CPT symmetry in decays of positronium atoms. This test is performed via determination of the expectation value of operators that are odd under discrete symmetries. The J-PET detector is optimized for the registration of photons from electron–positron annihilations, and such operators may be constructed from the spin of ortho-positronium atoms and the momenta and polarization vectors of photons originating from its annihilation.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Inne
Tytuł:
Searching for VHE gamma-ray emission associated with IceCube neutrino alerts using FACT, H.E.S.S., MAGIC, and VERITAS
Autorzy:
Stawarz, Łukasz
Jamrozy, Marek
Ostrowski, Michał
Barnacka, Anna
Wierzcholska, Alicja
Noel, Angel
Współwytwórcy:
Współautorami artykułu są członkowie Magic Collaboration, IceCube Collaboration, FACT Collaboration, H.E.S.S. Collaboration, VERITAS Collaboration w liczbie 808
Opis:
The realtime follow-up of neutrino events is a promising approach to search for astrophysical neutrino sources. It has so far provided compelling evidence for a neutrino point source: the flaring gamma-ray blazar TXS 0506+056 observed in coincidence with the high-energy neutrino IceCube-170922A detected by IceCube. The detection of very-high-energy gamma rays (VHE, E > 100 GeV) from this source helped establish the coincidence and constrained the modeling of the blazar emission at the time of the IceCube event. The four major imaging atmospheric Cherenkov telescope arrays (IACTs) - FACT, H.E.S.S., MAGIC, and VERITAS - operate an active follow-up program of target-of-opportunity observations of neutrino alerts sent by IceCube. This program has two main components. One are the observations of known gamma-ray sources around which a cluster of candidate neutrino events has been identified by IceCube (Gamma-ray Follow-Up, GFU). Second one is the follow-up of single high-energy neutrino candidate events of potential astrophysical origin such as IceCube-170922A. GFU has been recently upgraded by IceCube in collaboration with the IACT groups. We present here recent results from the IACT follow-up programs of IceCube neutrino alerts and a description of the upgraded IceCube GFU system.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Inne
Tytuł:
GWTC-4.0 : an introduction to version 4.0 of the Gravitational-Wave Transient Catalog
Autorzy:
Kubisz, Jerzy
Współwytwórcy:
Współautorami artykułu są członkowie LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration w liczbie 1807
Opis:
The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational-wave signals identified by the LIGO–Virgo–KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal’s source as inferred from the observational data. GWTC is the data release of this dataset, and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO–Virgo–KAGRA observing run up until 2024 January 31. This Letter marks an introduction to a collection of articles related to this version of the catalog, GWTC-4.0. The collection of articles accompanying the catalog provides documentation of the methods used to analyze the data, summaries of the catalog of events, observational measurements drawn from the population, and detailed discussions of selected candidates.
Dostawca treści:
Repozytorium Uniwersytetu Jagiellońskiego
Artykuł

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