The universal Teukolsky equations and black hole perturbations in higher-derivative gravity

We reduce the study of perturbations of rotating black holes in higher-derivative extensions of general relativity to a system of decoupled radial equations that stem from a set of universal Teukolsky equations. We detail a complete computational strategy to obtain these decoupled equations in general higher-derivative theories. We apply this to six-derivative gravity to compute the shifts in the quasinormal mode frequencies with respect to those of Kerr black holes in general relativity. At linear order in the angular momentum we reproduce earlier results obtained with a metric perturbation approach. In contrast with this earlier work, however, the method given here applies also to post-merger black holes with significant spin, which are of particular observational interest.Comment: 50 pages, 5 figures. v2: we fixed an error in our code and this led to improved results for the QNMs reported in section 6. The rest of the sections remain unchanged up to small adjustements. Conclusions unchanged. Version sent to the journal. We provide an ancillary Mathematica notebook with the modified Teukolsky radial equations for the (l,m)=(2,3) and (3,3) modes in six-derivative gravit

Quasinormal modes of rotating black holes in higher-derivative gravity

We compute the spectrum of linearized gravitational excitations of black holes with substantial angular momentum in the presence of higher-derivative corrections to general relativity. We do so perturbatively to leading order in the higher-derivative couplings and up to order fourteen in the black hole angular momentum. This allows us to accurately predict quasinormal mode frequencies of black holes with spins up to about $70\%$ of the extremal value. For some higher-derivative corrections, we find that sizable rotation enhances the frequency shifts by almost an order of magnitude relative to the static case.Comment: 5 pages+appendices, 2 figure

KinOath Kinship Archiver Version 1.4

This talk will introduce a new tool for Humanities research, in particular Ethnology, Linguistics, Law, History, but also Genetics and Archiving. This tool is KinOath Kinship Archiver which is an application for collecting and analysing kinship data. It is designed to be flexible and culturally nonspecific, which is important to prevent extraneous concepts being imposed onto the data being recorded. The kinship data can be linked to external resources such as archive data. Graphical representation of the data is a key feature, it produces publishable quality diagrams that can be exported to SVG, PDF and JPG formats. Data can be imported from GEDCOM, CSV and TIP files. Data can be exported into CSV format, with additional formats becoming available as plugins. KinOath provides very flexible data fields for each individual / entity recorded in the kinship data, this is combined with customisable relation types, customisable symbols and customisable kin types. This means, for example, that any number of genders and kinship relations can be defined and represented on a diagram. The most common format, GEDCOM (Family History Department, 1999), can be imported into KinOath. However this GEDCOM format exhibits cultural specificities because it has a predetermined set of kinship types, genders and initiation ceremonies. We know that there is a wider array of kinship types (e.g. suckling relations (Altorki, 1980)) and genders (e.g. the Māhū of Hawaiʻi (Matzner, 2001)). There are also initiation ceremonies beyond the Christian and Jewish ceremonies that are predefined in GEDCOM. However once this data is imported, all the flexibility of KinOath will be available. KinOath has project based diagrams and freeform diagrams. Freeform diagrams are like a quick sketch; while project diagrams each have a database of kinship data which can be shared across multiple diagrams. Project based diagrams also allow kin type string queries, such that individuals to be found based on their relations to others. Individuals in a project diagram can be duplicated and merged, which can be useful, for example, in correcting data, or merging multiple data sets where some individuals overlap. In freeform diagrams kin terms can be defined with kin type strings and shown on the diagram, organised in groups, imported and exported. In the future it will be possible to overlay these kin terms onto project diagrams. In order to perform statistical analysis, the kinship data for each project or freeform diagram can be exported for use in R or SPSS. This combined with queries based on kin types and other search parameters, provides great potential in the analysis of both the kin data and the archive data that has been recorded. The intended users of Kinoath are any researchers that collect data in a context of social relations. Kinship data is often not systematically included in the metadata of archives, however these kin relations provide a context that enriches that archived data. KinOath is in active development and new features are regularly being added. The plugin framework that KinOath shares with Arbil has made it possible for external developers to add features. The various versions and the manual are available at: http://tla.mpi.nl/tools/tlatools/kinoath/ REFERENCES Family History Department of The Church of Jesus Christ of Latterday Saints, 1999, THE GEDCOM STANDARD DRAFT Release 5.5.1 http://www.phpgedview.net/ged551¬5.pdf Matzner, Andrew. 2001. 'O au no keia: voices from Hawaii's Mahu and transgender communities. Bloomington, Indiana: Xlibris. Altorki, Soraya. 1980. MilkKinship in Arab Society: An Unexplored Problem in the Ethnography of Marriage. Ethnology 19(2): 233-24

Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass $M>70$ $M_\odot$) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities $0 < e \leq 0.3$ at $0.33$ Gpc$^{-3}$ yr$^{-1}$ at 90\% confidence level.Comment: 24 pages, 5 figure

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame mass M > 70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e ≤ 0.3 at 16.9 Gpc−3 yr−1 at the 90% confidence level

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M&gt;70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0&lt;e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Observation of gravitational waves from the coalescence of a 2.5–4.5 M ⊙ compact object and a neutron star

We report the observation of a coalescing compact binary with component masses 2.5–4.5 M ⊙ and 1.2–2.0 M ⊙ (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 ⊙ 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 55−47+127Gpc−3yr−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

Ruth - Een woord van trouw

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