Search

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far.

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 observing run. This background is the accumulated signal from unresolved sources throughout cosmic history and encodes information about the merger history of compact binaries throughout the Universe, as well as exotic physics and potentially primordial processes from the early cosmos. Our cross-correlation analysis reveals no statistically significant background signal, enabling us to constrain several theoretical scenarios. For compact binary coalescences which approximately follow a $2/3$ power-law spectrum, we constrain the fractional energy density to ${\mathrm{\Omega }}_{\mathrm{GW}}(25\mathrm{Hz})\le 2.0\times {10}^{-9}$ (95% credibility), a factor of 1.7 improvement over previous results. Scale-invariant backgrounds are constrained to ${\mathrm{\Omega }}_{\mathrm{GW}}(25\mathrm{Hz})\le 2.8\times {10}^{-9}$, representing a $2.1\times$ sensitivity gain. We also place new limits on alternative gravity theories predicting nonstandard polarization modes and confirm that terrestrial magnetic noise sources remain below our detection threshold. Combining these spectral limits with population models for Gravitational-Wave Transient Catalog (GWTC)-4, the latest gravitational-wave event catalog, we find our constraints remain above predicted merger backgrounds but are approaching detectability. The joint analysis combining the background limits shown here with GWTC-4 enables improved inference of the binary black hole merger rate evolution across cosmic time. Furthermore, employing GWTC-4 inference results and standard modeling choices, we estimate that the total background arising from compact binary coalescences is ${\mathrm{\Omega }}_{\mathrm{CBC}}(25\mathrm{Hz})={0.9}_{-0.5}^{+1.1}\times {10}^{-9}$ at 90% confidence, where the largest contribution is due to binary black holes only, ${\mathrm{\Omega }}_{\mathrm{BBH}}(25\mathrm{Hz})={0.8}_{-0.5}^{+1.1}\times {10}^{-9}$.

We present a search of data from the first part of the fourth observing run of LIGO-Virgo-KAGRA for three kinds of dark matter—dilatons (spin-0), dark photons (spin-1), and tensor bosons (spin-2)—using three independent methods, each extended to search for all three candidates. Each dark matter candidate could interact with different standard-model particles in the instruments, causing unique differential strains on the interferometers. While we do not find any evidence for a signal, we place the most stringent upper limits to date on the couplings of each dark matter model to the interferometers. For scalars with masses between $[4\times {10}^{-14},1.5\times {10}^{-13}]\mathrm{eV}$ that couple to photons or electrons, our constraints on the scalar-to-electron or photon coupling improve upon those from the third observing run by 1 order of magnitude, with the tightest limit of $\sim {10}^{-20}{\mathrm{GeV}}^{-1}$ at a mass of $\sim 2\times {10}^{-13}\mathrm{eV}$. For vectors with masses between $[7\times {10}^{-13},8.47\times {10}^{-12}]\mathrm{eV}$ that couple to baryons, our constraints on the dark-photon or baryon coupling supersede those from MICROSCOPE and Eöt-Wash by 1 to 2 orders of magnitude, reaching a minimum of $\sim 5\times {10}^{-24}$ at a mass of $\sim {10}^{-12}\mathrm{eV}$. For tensors with masses of $[4\times {10}^{-14},8.47\times {10}^{-12}]\mathrm{eV}$ (the full mass range analyzed) that couple via a Yukawa interaction, our constraints, which are the first obtained from gravitational-wave interferometers, surpass those from fifth-force experiments by 4 to 5 orders of magnitude, achieving a limit as low as $\sim 8\times {10}^{-9}$ at $\sim 2\times {10}^{-13}\mathrm{eV}$. Our results show that each method has substantially different sensitivity to each dark matter candidate, highlighting the importance of a multimethod approach to search for new physics. Moreover, they demonstrate that gravitational-wave interferometers can simultaneously probe multiple ultralight dark matter models and place unprecedented constraints on tensor fields arising in a broad range of modified-gravity theories.

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 between May 24, 2023, and January 16, 2024. The GW signals targeted by this search are the so-called “long-duration” ($\gtrsim 1\mathrm{s}$) transients expected from a variety of astrophysical processes, including nonaxisymmetric deformations in magnetars or eccentric binary coalescences. We make minimal assumptions on the emitted GW waveforms in terms of morphologies and durations. Overall, our search targets signals with durations of $\sim 1–1000\mathrm{s}$ and frequency content in the range 16–2048 Hz. In the absence of significant detections, we report the sensitivity limits of our search in terms of root-sum-square signal amplitude ($h_{\mathrm{rss}}$) of reference waveforms. These limits improve upon the results from the third LIGO-Virgo-KAGRA observing run (O3) by about 30% on average. Moreover, this analysis demonstrates substantial progress in our ability to search for long-duration GW signals owing to enhancements in pipeline detection efficiencies. As detector sensitivities continue to advance and observational runs grow longer, unmodeled long-duration searches will increasingly be able to explore a range of compelling astrophysical scenarios involving neutron stars and black holes.

The third Gravitational-Wave Transient Catalog (GWTC-3) describes signals detected with Advanced LIGO and Advanced Virgo up to the end of their third observing run. Updating the previous GWTC-2.1, we present candidate gravitational waves from compact binary coalescences during the second half of the third observing run (O3b) between 1 November 2019, $15:00$ Coordinated Universal Time (UTC) and 27 March 2020, $17:00$ UTC. There are 35 compact binary coalescence candidates identified by at least one of our search algorithms with a probability of astrophysical origin $p_{\text{astro}}>0.5$. Of these, 18 were previously reported as low-latency public alerts, and 17 are reported here for the first time. Based upon estimates for the component masses, our O3b candidates with $p_{\text{astro}}>0.5$ are consistent with gravitational-wave signals from binary black holes or neutron-star–black-hole binaries, and we identify none from binary neutron stars. However, from the gravitational-wave data alone, we are not able to measure matter effects that distinguish whether the binary components are neutron stars or black holes. The range of inferred component masses is similar to that found with previous catalogs, but the O3b candidates include the first confident observations of neutron-star–black-hole binaries. Including the 35 candidates from O3b in addition to those from GWTC-2.1, GWTC-3 contains 90 candidates found by our analysis with $p_{\text{astro}}>0.5$ across the first three observing runs. These observations of compact binary coalescences present an unprecedented view of the properties of black holes and neutron stars.

We analyze the impact of a proposed tidal instability coupling $p$ modes and $g$ modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor ($\ln B_{!pg}^{pg}$) comparing our $p\text{−}g$ model to a standard one. We find that the observed signal is consistent with waveform models that neglect $p\text{−}g$ effects, with $\ln B_{!pg}^{pg}=0.03_{-0.58}^{+0.70}$ (maximum a posteriori and 90% credible region). By injecting simulated signals that do not include $p\text{−}g$ effects and recovering them with the $p\text{−}g$ model, we show that there is a $\simeq 50\%$ probability of obtaining similar $\ln B_{!pg}^{pg}$ even when $p\text{−}g$ effects are absent. We find that the $p\text{−}g$ amplitude for $1.4M_{\odot }$ neutron stars is constrained to less than a few tenths of the theoretical maximum, with maxima a posteriori near one-tenth this maximum and $p\text{−}g$ saturation frequency $\sim 70\mathrm{Hz}$. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest $\lesssim {10}^3$ modes saturate by wave breaking. Thus, the measured constraints only rule out extreme values of the $p\text{−}g$ parameters. They also imply that the instability dissipates $\lesssim 10^{51}\mathrm{erg}$ over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.

On August 17, 2017, the Advanced LIGO and Advanced Virgo gravitational-wave detectors observed a low-mass compact binary inspiral. The initial sky localization of the source of the gravitational-wave signal, GW170817, allowed electromagnetic observatories to identify NGC 4993 as the host galaxy. In this work, we improve initial estimates of the binary’s properties, including component masses, spins, and tidal parameters, using the known source location, improved modeling, and recalibrated Virgo data. We extend the range of gravitational-wave frequencies considered down to 23 Hz, compared to 30 Hz in the initial analysis. We also compare results inferred using several signal models, which are more accurate and incorporate additional physical effects as compared to the initial analysis. We improve the localization of the gravitational-wave source to a 90% credible region of $16{\mathrm{deg}}^2$. We find tighter constraints on the masses, spins, and tidal parameters, and continue to find no evidence for nonzero component spins. The component masses are inferred to lie between 1.00 and $1.89{\mathrm{M}}_{\odot }$ when allowing for large component spins, and to lie between 1.16 and $1.60{\mathrm{M}}_{\odot }$ (with a total mass ${2.73}_{-0.01}^{+0.04}{\mathrm{M}}_{\odot }$) when the spins are restricted to be within the range observed in Galactic binary neutron stars. Using a precessing model and allowing for large component spins, we constrain the dimensionless spins of the components to be less than 0.50 for the primary and 0.61 for the secondary. Under minimal assumptions about the nature of the compact objects, our constraints for the tidal deformability parameter $\tilde{\mathrm{\Lambda }}$ are (0,630) when we allow for large component spins, and ${300}_{-230}^{+420}$ (using a 90% highest posterior density interval) when restricting the magnitude of the component spins, ruling out several equation-of-state models at the 90% credible level. Finally, with LIGO and GEO600 data, we use a Bayesian analysis to place upper limits on the amplitude and spectral energy density of a possible postmerger signal.

We present directed searches for continuous gravitational waves from the neutron stars in the Cassiopeia A (Cas A) and Vela Jr. supernova remnants. We carry out the searches in the LIGO detector data from the first six months of the third Advanced LIGO and Virgo observing run using the weave semicoherent method, which sums matched-filter detection-statistic values over many time segments spanning the observation period. No gravitational wave signal is detected in the search band of 20–976 Hz for assumed source ages greater than 300 years for Cas A and greater than 700 years for Vela Jr. Estimates from simulated continuous wave signals indicate we achieve the most sensitive results to date across the explored parameter space volume, probing to strain magnitudes as low as $\sim 6.3\times {10}^{-26}$ for Cas A and $\sim 5.6\times {10}^{-26}$ for Vela Jr. at frequencies near 166 Hz at 95% efficiency.

We present a directed search for continuous gravitational wave (CW) signals emitted by spinning neutron stars located in the inner parsecs of the Galactic Center (GC). Compelling evidence for the presence of a numerous population of neutron stars has been reported in the literature, turning this region into a very interesting place to look for CWs. In this search, data from the full O3 LIGO-Virgo run in the detector frequency band $[10,2000]\mathrm{Hz}$ have been used. No significant detection was found and 95% confidence level upper limits on the signal strain amplitude were computed, over the full search band, with the deepest limit of about $7.6\times {10}^{-26}$ at $\simeq 142\mathrm{Hz}$. These results are significantly more constraining than those reported in previous searches. We use these limits to put constraints on the fiducial neutron star ellipticity and r-mode amplitude. These limits can be also translated into constraints in the black hole mass–boson mass plane for a hypothetical population of boson clouds around spinning black holes located in the GC.

Results are presented for a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to allow for spin wandering. This search improves on previous HMM-based searches of Laser Interferometer Gravitational-Wave Observatory data by including the orbital period in the search template grid, and by analyzing data from the latest (third) observing run. In the frequency range searched, from 60 to 500 Hz, we find no evidence of gravitational radiation. This is the most sensitive search for Scorpius X-1 using a HMM to date. For the most sensitive subband, starting at 256.06 Hz, we report an upper limit on gravitational wave strain (at 95% confidence) of $h_0^{95\%}=6.16\times {10}^{-26}$, assuming the orbital inclination angle takes its electromagnetically restricted value $\iota =44°$. The upper limits on gravitational wave strain reported here are on average a factor of $\sim 3$ lower than in the second observing run HMM search. This is the first Scorpius X-1 HMM search with upper limits that reach below the indirect torque-balance limit for certain subbands, assuming $\iota =44°$.

Rapidly spinning neutron stars are promising sources of continuous gravitational waves. Detecting such a signal would allow probing of the physical properties of matter under extreme conditions. A significant fraction of the known pulsar population belongs to binary systems. Searching for unknown neutron stars in binary systems requires specialized algorithms to address unknown orbital frequency modulations. We present a search for continuous gravitational waves emitted by neutron stars in binary systems in early data from the third observing run of the Advanced LIGO and Advanced Virgo detectors using the semicoherent, GPU-accelerated, binaryskyhough pipeline. The search analyzes the most sensitive frequency band of the LIGO detectors, 50–300 Hz. Binary orbital parameters are split into four regions, comprising orbital periods of three to 45 days and projected semimajor axes of two to 40 light seconds. No detections are reported. We estimate the sensitivity of the search using simulated continuous wave signals, achieving the most sensitive results to date across the analyzed parameter space.

This paper presents the results of a search for generic short-duration gravitational-wave transients in data from the third observing run of Advanced LIGO and Advanced Virgo. Transients with durations of milliseconds to a few seconds in the 24–4096 Hz frequency band are targeted by the search, with no assumptions made regarding the incoming signal direction, polarization, or morphology. Gravitational waves from compact binary coalescences that have been identified by other targeted analyses are detected, but no statistically significant evidence for other gravitational wave bursts is found. Sensitivities to a variety of signals are presented. These include updated upper limits on the source rate density as a function of the characteristic frequency of the signal, which are roughly an order of magnitude better than previous upper limits. This search is sensitive to sources radiating as little as $\sim {10}^{-10}{M}_{\odot }{c}^2$ in gravitational waves at $\sim 70\mathrm{Hz}$ from a distance of 10 kpc, with 50% detection efficiency at a false alarm rate of one per century. The sensitivity of this search to two plausible astrophysical sources is estimated: neutron star $f$ modes, which may be excited by pulsar glitches, as well as selected core-collapse supernova models.

This paper describes the first all-sky search for long-duration, quasimonochromatic gravitational-wave signals emitted by ultralight scalar boson clouds around spinning black holes using data from the third observing run of Advanced LIGO. We analyze the frequency range from 20 to 610 Hz, over a small frequency derivative range around zero, and use multiple frequency resolutions to be robust towards possible signal frequency wanderings. Outliers from this search are followed up using two different methods, one more suitable for nearly monochromatic signals, and the other more robust towards frequency fluctuations. We do not find any evidence for such signals and set upper limits on the signal strain amplitude, the most stringent being $\approx {10}^{-25}$ at around 130 Hz. We interpret these upper limits as both an “exclusion region” in the boson mass/black hole mass plane and the maximum detectable distance for a given boson mass, based on an assumption of the age of the black hole/boson cloud system.

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension $G\mu$ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO–Virgo constraints on $G\mu$ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: $G\mu \lesssim 4\times {10}^{-15}$. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

GW240925 and GW250207 are two loud gravitational-wave signals from binary black hole coalescences observed with network signal-to-noise ratios $\sim 32$ and $\sim 69$, respectively, by the LIGO Hanford-LIGO Livingston-Virgo network. Gravitational-wave signals from coalescing binaries have characteristic phase and amplitude evolution predicted by general relativity. These signal waveforms, together with measured instrumental calibration uncertainties, are used to infer source parameters. However, for sufficiently loud detections, it is possible to constrain the calibration of the detectors directly using the signals themselves. We present the first informative astrophysical measurements of gravitational-wave detector calibration. For GW240925, we verify the inference of Hanford calibration from the astrophysical signal through cross-checks with known calibration errors obtained from in situ measurements. At the time of GW250207, the Hanford detector was not fully stabilized, leading to elevated calibration uncertainties; thus, astrophysical calibration is essential to obtain accurate data and to enable source localization. These well-localized, high signal-to-noise observations have the potential to offer precise measurements of source properties, stringent tests of general relativity, and informative dark siren measurements, provided that calibration uncertainties are properly incorporated. As detector sensitivity improves, astrophysical calibration will become an increasingly valuable complement to in situ calibration measurements. Obtaining accurate calibration will be essential for precision gravitational-wave science.

We report on a new all-sky search for periodic gravitational waves in the frequency band 475–2000 Hz and with a frequency time derivative in the range of $[-1.0,+0.1]\times 10^{-8}\mathrm{Hz}/\mathrm{s}$. Potential signals could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the data from Advanced LIGO’s first observational run O1. No gravitational-wave signals were observed, and upper limits were placed on their strengths. For completeness, results from the separately published low-frequency search 20–475 Hz are included as well. Our lowest upper limit on worst-case (linearly polarized) strain amplitude $h_0$ is $\sim 4\times 10^{-25}$ near 170 Hz, while at the high end of our frequency range, we achieve a worst-case upper limit of $1.3\times 10^{-24}$. For a circularly polarized source (most favorable orientation), the smallest upper limit obtained is $\sim 1.5\times 10^{-25}$.

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function $p(\rho )$ of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as $R_1={10.8}_{-1.7}^{+2.0}\mathrm{km}$ for the heavier star and $R_2={10.7}_{-1.5}^{+2.1}\mathrm{km}$ for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than $1.97{\mathrm{M}}_{\odot }$ as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain $R_1={11.9}_{-1.4}^{+1.4}\mathrm{km}$ and $R_2={11.9}_{-1.4}^{+1.4}\mathrm{km}$ at the 90% credible level. Finally, we obtain constraints on $p(\rho )$ at supranuclear densities, with pressure at twice nuclear saturation density measured at ${3.5}_{-1.7}^{+2.7}\times {10}^{34}\text{dyn}{\mathrm{cm}}^{-2}$ at the 90% level.

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between $0.2M_{\odot }–1.0M_{\odot }$ using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning ($0.2M_{\odot }$, $0.2M_{\odot }$) ultracompact binaries to be less than $1.0\times {10}^6{\mathrm{Gpc}}^{-3}{\mathrm{yr}}^{-1}$ and the coalescence rate of a similar distribution of ($1.0M_{\odot }$, $1.0M_{\odot }$) ultracompact binaries to be less than $1.9\times {10}^4{\mathrm{Gpc}}^{-3}{\mathrm{yr}}^{-1}$ (at 90% confidence). Neither black holes nor neutron stars are expected to form below $\sim 1M_{\odot }$ through conventional stellar evolution, though it has been proposed that similarly low mass black holes could be formed primordially through density fluctuations in the early Universe and contribute to the dark matter density. The interpretation of our constraints in the primordial black hole dark matter paradigm is highly model dependent; however, under a particular primordial black hole binary formation scenario we constrain monochromatic primordial black hole populations of $0.2M_{\odot }$ to be less than 33% of the total dark matter density and monochromatic populations of $1.0M_{\odot }$ to be less than 5% of the dark matter density. The latter strengthens the presently placed bounds from microlensing surveys of massive compact halo objects (MACHOs) provided by the MACHO and EROS Collaborations.

On August 17, 2017 at 12∶41:04 UTC the Advanced LIGO and Advanced Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with a combined signal-to-noise ratio of 32.4 and a false-alarm-rate estimate of less than one per $8.0\times {10}^4\mathrm{years}$. We infer the component masses of the binary to be between 0.86 and $2.26M_{\odot }$, in agreement with masses of known neutron stars. Restricting the component spins to the range inferred in binary neutron stars, we find the component masses to be in the range $1.17–1.60M_{\odot }$, with the total mass of the system $2.74_{-0.01}^{+0.04}{M}_{\odot }$. The source was localized within a sky region of $28{\mathrm{deg}}^2$ (90% probability) and had a luminosity distance of $40_{-14}^{+8}\mathrm{Mpc}$, the closest and most precisely localized gravitational-wave signal yet. The association with the $\gamma$-ray burst GRB 170817A, detected by Fermi-GBM 1.7 s after the coalescence, corroborates the hypothesis of a neutron star merger and provides the first direct evidence of a link between these mergers and short $\gamma$-ray bursts. Subsequent identification of transient counterparts across the electromagnetic spectrum in the same location further supports the interpretation of this event as a neutron star merger. This unprecedented joint gravitational and electromagnetic observation provides insight into astrophysics, dense matter, gravitation, and cosmology.

We present a search for dark photon dark matter that could couple to gravitational-wave interferometers using data from Advanced LIGO and Virgo’s third observing run. To perform this analysis, we use two methods, one based on cross-correlation of the strain channels in the two nearly aligned LIGO detectors, and one that looks for excess power in the strain channels of the LIGO and Virgo detectors. The excess power method optimizes the Fourier transform coherence time as a function of frequency, to account for the expected signal width due to Doppler modulations. We do not find any evidence of dark photon dark matter with a mass between $m_{\mathrm{A}}\sim {10}^{-14}–{10}^{-11}\mathrm{eV}/c^2$, which corresponds to frequencies between 10–2000 Hz, and therefore provide upper limits on the square of the minimum coupling of dark photons to baryons, i.e., $U(1{)}_{\mathrm{B}}$ dark matter. For the cross-correlation method, the best median constraint on the squared coupling is $\sim 1.31\times {10}^{-47}$ at $m_{\mathrm{A}}\sim 4.2\times {10}^{-13}\mathrm{eV}/c^2$; for the other analysis, the best constraint is $\sim 2.4\times {10}^{-47}$ at $m_{\mathrm{A}}\sim 5.7\times {10}^{-13}\mathrm{eV}/c^2$. These limits improve upon those obtained in direct dark matter detection experiments by a factor of $\sim 100$ for $m_{\mathrm{A}}\sim [2–4]\times {10}^{-13}\mathrm{eV}/c^2$, and are, in absolute terms, the most stringent constraint so far in a large mass range $m_A\sim 2\times {10}^{-13}–8\times {10}^{-12}\mathrm{eV}/c^2$.