{"work":{"id":"ecdcd896-0d01-4707-9631-446c2f7bb47b","openalex_id":null,"doi":"10.3847/2041-8213/acd","arxiv_id":"2306.16213","raw_key":null,"title":"The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background","authors":null,"authors_text":"Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Becsy","year":2023,"venue":"astro-ph.HE","abstract":"We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15-year pulsar-timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings-Downs pattern expected for a stochastic gravitational-wave background. The presence of such a gravitational-wave background with a power-law-spectrum is favored over a model with only independent pulsar noises with a Bayes factor in excess of $10^{14}$, and this same model is favored over an uncorrelated common power-law-spectrum model with Bayes factors of 200-1000, depending on spectral modeling choices. We have built a statistical background distribution for these latter Bayes factors using a method that removes inter-pulsar correlations from our data set, finding $p = 10^{-3}$ (approx. $3\\sigma$) for the observed Bayes factors in the null no-correlation scenario. A frequentist test statistic built directly as a weighted sum of inter-pulsar correlations yields $p = 5 \\times 10^{-5} - 1.9 \\times 10^{-4}$ (approx. $3.5 - 4\\sigma$). Assuming a fiducial $f^{-2/3}$ characteristic-strain spectrum, as appropriate for an ensemble of binary supermassive black-hole inspirals, the strain amplitude is $2.4^{+0.7}_{-0.6} \\times 10^{-15}$ (median + 90% credible interval) at a reference frequency of 1/(1 yr). The inferred gravitational-wave background amplitude and spectrum are consistent with astrophysical expectations for a signal from a population of supermassive black-hole binaries, although more exotic cosmological and astrophysical sources cannot be excluded. The observation of Hellings-Downs correlations points to the gravitational-wave origin of this signal.","external_url":"https://arxiv.org/abs/2306.16213","cited_by_count":null,"metadata_source":"pith","metadata_fetched_at":"2026-07-10T06:15:00.866473+00:00","pith_arxiv_id":"2306.16213","created_at":"2026-05-09T05:50:27.445269+00:00","updated_at":"2026-07-11T11:50:26.030339+00:00","title_quality_ok":true,"display_title":"The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background","render_title":"The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background"},"hub":{"state":{"work_id":"ecdcd896-0d01-4707-9631-446c2f7bb47b","tier":"super_hub","tier_reason":"100+ Pith inbound or 10,000+ external citations","pith_inbound_count":112,"external_cited_by_count":null,"distinct_field_count":7,"first_pith_cited_at":"2023-07-20T10:14:35+00:00","last_pith_cited_at":"2026-07-08T14:41:22+00:00","author_build_status":"needed","summary_status":"needed","contexts_status":"needed","graph_status":"needed","ask_index_status":"needed","reader_status":"not_needed","recognition_status":"not_needed","updated_at":"2026-08-21T02:49:30.430852+00:00","tier_text":"super_hub"},"tier":"super_hub","role_counts":[{"context_role":"background","n":29},{"context_role":"dataset","n":3},{"context_role":"extension","n":1},{"context_role":"method","n":1}],"polarity_counts":[{"context_polarity":"background","n":27},{"context_polarity":"use_dataset","n":3},{"context_polarity":"extend","n":1},{"context_polarity":"support","n":1},{"context_polarity":"unclear","n":1},{"context_polarity":"use_method","n":1}],"runs":{"ask_index":{"job_type":"ask_index","status":"succeeded","result":{"title":"The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background","claims":[{"claim_text":"We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15-year pulsar-timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings-Downs pattern expected for a stochastic gravitational-wave background. The presence of such a gravitational-wave background with a power-law-spectrum is favored over a model with only independent pulsar noises with a Bayes factor in excess of $10^{14}$, and this same model is favored over an uncorrelated common power-law-spectrum model with Baye","claim_type":"abstract","evidence_strength":"source_metadata"},{"claim_text":"sient catalogs GWTC-1 through GWTC-3 [2-4]. These observations have transformed gravitational-wave astron- omy into a precision discipline, enabling detailed tests of strong-field gravity and compact-object population stud- ies. In parallel, pulsar timing arrays, including NANOGrav, have recently reported evidence for a stochastic nanohertz gravitational-wave background [5], opening a complementary low-frequency window onto su- permassive black hole binaries and possible cosmological sources. 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Lett. 951, L8 (2023), arXiv:2306.16213 [astro-ph.HE]. [4] G. Agazie et al. (NANOGrav), Astrophys. J. Lett. 951, L9 (2023), arXiv:2306.16217 [astro-ph.HE]. [5] G. Agazie et al. (NANOGrav), (2023), arXiv:2","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"Ever since the first detection of a gravitational wave event by LIGO [183], several large observatories are projected, e.g., LISA [184], Taiji [185], TianQin [185] and the Einstein Telescope [186]. In addi- tion to the detection of singular events, the gravitational wave background has also been recently detected by Pulsar Timing Array collaborations (e.g., NANOGrav, [187], CPTA [188], EPTA, [189]). Regarding FRBs, current radio observatories regularly detect these events, compiling ever-growing","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"be the detection of a stochastic primordial gravitational wave background, and the future gravitational wave experiments will operate in frequency bands that will probe the inflationary gravitational waves [6-14]. NANOGrav already verified a stochastic gravitational wave background back in 2023 [15], but inflation itself cannot generate such a signal [16, 17]. Thus the next ten years will be extremely important for modern theoretical physics. Recently, the Atacama Cosmology Telescope (ACT) [18, ","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"turbation equations in certain higher-dimensional scenar - ios due to the influence of the bulk on the brane [55, 56]. Secondly, massive gravitons, either in explicit massive gravity theories or as effective degrees of freedom, have been argued to contribute to very long-wavelength grav- itational signals [57], which are currently being probed by Pulsar Timing Array experiments [58, 59]. Thirdly, massive fields may support arbitrarily long-lived QNMs for particular values of the field mass, leading ","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"}],"why_cited":"Pith tracks The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background because it crossed a citation-hub threshold. 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[30]. Among them,Cosmic Strings(CSs) attract a fair amount of attention currently since they contribute to the CMB and generate [31] a stochastic back- ground ofgravitational waves(GWs) in the nanohertz range, probed bypulsar timing arrays(PT As) such asNANOGrav (15-yr)[32],EPTA[33],PPTA[34], andCPTA[35]. The tension of CSs is directly linked to the symmetry-breaking scale ofG, connecting ACT/SPT-preferred inflationary parameters with the spectrum of the GWs observed by PTAs - see, e.g., Ref. [15, 36-42]. For a reliable approach to FHI, soft SUSY-breaking terms [43-50] andSupergravity(SUGRA) cor- rections [51-55] have to be taken into account together with theradiative corrections(RCs) employed","citing_arxiv_id":"2605.08931"},{"n":1,"role":"method","polarity":"use_method","paper_title":"Imprint of domain wall annihilation on induced gravitational waves","primary_cat":"hep-ph","context_text":"annihilation and the onset of standard radiation domina- tion, bothΩpeak andf peak are modified. The peak ampli- tude is suppressed by the entropy dilution factor, while the peak frequency is redshifted according to the expan- sion history during and after the MD epoch. Incorporat- ing these modifications, we describe the GW spectrum using the broken power-law parametrization introduced 6 in Refs.[2, 105]: ΩGWh2 = Ωph2 D4/3 (a+b) c \u0012 b \u0010 D1/3 f fp \u0011−a/c +a \u0010 D1/3 f fp \u0011b/c\u0013c ,(36) wherea,bandcare real and positive parameters. Here the low-frequency slope4 a= 3can be fixed by causality, while numerical simulations suggestb≃c≃1[96]. InFig. 3, wefirstpresentthepower-lawintegratedsen- sitivity curves [106] of the future GW detectors ET [107], LISA [108], DECIGO [109],µAres [110], SKA [111], and","citing_arxiv_id":"2604.25726"},{"n":1,"role":"dataset","polarity":"use_dataset","paper_title":"Forecasting graviton-mass constraints from the full covariance of PTA-astrometry ORF estimators","primary_cat":"gr-qc","context_text":"containing the PTA, astrometric, and cross-channel observables. Using Hierarchical Equal Area isoLatitude Pixelation of a sphere (HEALPix) [51], we discretize the celestial sphere into a finite set of pixels, denoted byN pix. The fiducial model is the general-relativistic limit mg = 0 (ϵ= 0), with an injected power-law SGWB (A GWB, α) = (2.4×10 −15,−2/3) [14, 46]. At each discrete frequencyf k, we assemble the covariance matrix of the all-sky three- component signal field from the global-basis pairwise correlation subblocksC glob xy defined by Eqs. (12) and (13). In the present implementation, this signal covariance has dimension 3Npix ×3N pix, corresponding to one PTA-like observable and two astrometric deflection","citing_arxiv_id":"2604.23384"},{"n":1,"role":"dataset","polarity":"use_dataset","paper_title":"Purely Quadratic Non-Gaussianity from Tachyonic Instability: Primordial Black Holes and Scalar-Induced Gravitational Waves","primary_cat":"astro-ph.CO","context_text":"Thermal inflation provides a useful benchmark scenario with asteroid-mass PBH dark matter and high-frequency scalar-induced gravitational waves potentially detectable by future space-based interferometers, but its typically broad spectra make it challenging to reconcile PTA observations with PBH constraints. I. INTRODUCTION The recent pulsar timing array (PTA) data releases by the NANOGrav [1, 2], EPTA (in combination with InPTA) [3-5], PPTA [6-8], and CPTA [9] collaborations have reported compelling evidence for the existence of a stochas- tic gravitational wave background (SGWB) in the nanohertz (nHz) band. These measurements exhibit a statistical preference for the Hellings-Downs correlation among pulsar pairs, widely regarded as the hallmark signature of an","citing_arxiv_id":"2604.20063"},{"n":1,"role":"extension","polarity":"extend","paper_title":"The Heavy Tailed Non-Gaussianity of the Supermassive Black Hole Gravitational Wave Background","primary_cat":"astro-ph.CO","context_text":"ries, some of which may become individually resolvable as the PTA sensitivity improves [16-19]. The background is static because these binaries are far from coalescence, and their emission is nearly monochromatic, but exhibits significant anisotropies [20-23] and polarization [22, 24]. Furthermore, the distribution of realizations shows sub- stantial deviations from Gaussianity [10, 24-29]. These are characterized most conveniently by the SMBH GW amplitude distribution (GWAD). Building on our earlier results [10, 24], we confirm that the high-amplitude tail of GWAD exhibits auniversal, model-independent power-law scaling∝A −4 arising from the possibility of having nearby sources. This should be contrasted with an exponentially suppressed Gaus-","citing_arxiv_id":"2604.08506"}]},"error":null,"updated_at":"2026-06-30T12:20:09.303002+00:00"},"identity_refresh":{"job_type":"identity_refresh","status":"succeeded","result":{"items":[{"title":"Qwen3 Technical Report","outcome":"unchanged","work_id":"25a4e30c-1232-48e7-9925-02fa12ba7c9e","resolver":"local_arxiv","confidence":0.98,"old_work_id":"25a4e30c-1232-48e7-9925-02fa12ba7c9e"}],"counts":{"fixed":0,"merged":0,"unchanged":1,"quarantined":0,"needs_external_resolution":0},"errors":[],"attempted":1},"error":null,"updated_at":"2026-06-30T12:20:04.715440+00:00"},"role_polarity":{"job_type":"role_polarity","status":"succeeded","result":{"title":"The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background","claims":[{"claim_text":"We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15-year pulsar-timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings-Downs pattern expected for a stochastic gravitational-wave background. The presence of such a gravitational-wave background with a power-law-spectrum is favored over a model with only independent pulsar noises with a Bayes factor in excess of $10^{14}$, and this same model is favored over an uncorrelated common power-law-spectrum model with Baye","claim_type":"abstract","evidence_strength":"source_metadata"},{"claim_text":"sient catalogs GWTC-1 through GWTC-3 [2-4]. These observations have transformed gravitational-wave astron- omy into a precision discipline, enabling detailed tests of strong-field gravity and compact-object population stud- ies. In parallel, pulsar timing arrays, including NANOGrav, have recently reported evidence for a stochastic nanohertz gravitational-wave background [5], opening a complementary low-frequency window onto su- permassive black hole binaries and possible cosmological sources. 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Lett. 951, L8 (2023), arXiv:2306.16213 [astro-ph.HE]. [4] G. Agazie et al. (NANOGrav), Astrophys. J. Lett. 951, L9 (2023), arXiv:2306.16217 [astro-ph.HE]. [5] G. Agazie et al. (NANOGrav), (2023), arXiv:2","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"Ever since the first detection of a gravitational wave event by LIGO [183], several large observatories are projected, e.g., LISA [184], Taiji [185], TianQin [185] and the Einstein Telescope [186]. In addi- tion to the detection of singular events, the gravitational wave background has also been recently detected by Pulsar Timing Array collaborations (e.g., NANOGrav, [187], CPTA [188], EPTA, [189]). 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Lett. 951, L8 (2023), arXiv:2306.16213 [astro-ph.HE]. [4] G. Agazie et al. (NANOGrav), Astrophys. J. Lett. 951, L9 (2023), arXiv:2306.16217 [astro-ph.HE]. [5] G. Agazie et al. (NANOGrav), (2023), arXiv:2","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"Ever since the first detection of a gravitational wave event by LIGO [183], several large observatories are projected, e.g., LISA [184], Taiji [185], TianQin [185] and the Einstein Telescope [186]. In addi- tion to the detection of singular events, the gravitational wave background has also been recently detected by Pulsar Timing Array collaborations (e.g., NANOGrav, [187], CPTA [188], EPTA, [189]). Regarding FRBs, current radio observatories regularly detect these events, compiling ever-growing","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"be the detection of a stochastic primordial gravitational wave background, and the future gravitational wave experiments will operate in frequency bands that will probe the inflationary gravitational waves [6-14]. NANOGrav already verified a stochastic gravitational wave background back in 2023 [15], but inflation itself cannot generate such a signal [16, 17]. Thus the next ten years will be extremely important for modern theoretical physics. Recently, the Atacama Cosmology Telescope (ACT) [18, ","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"turbation equations in certain higher-dimensional scenar - ios due to the influence of the bulk on the brane [55, 56]. Secondly, massive gravitons, either in explicit massive gravity theories or as effective degrees of freedom, have been argued to contribute to very long-wavelength grav- itational signals [57], which are currently being probed by Pulsar Timing Array experiments [58, 59]. Thirdly, massive fields may support arbitrarily long-lived QNMs for particular values of the field mass, leading ","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"}],"why_cited":"Pith tracks The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background because it crossed a citation-hub threshold. Current citing contexts most often use it as background evidence (27 contexts).","role_counts":[{"n":27,"context_role":"background"},{"n":3,"context_role":"dataset"},{"n":1,"context_role":"extension"},{"n":1,"context_role":"method"}]},"error":null,"updated_at":"2026-06-30T12:19:52.318565+00:00"}},"summary":{"title":"The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background","claims":[{"claim_text":"We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15-year pulsar-timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings-Downs pattern expected for a stochastic gravitational-wave background. The presence of such a gravitational-wave background with a power-law-spectrum is favored over a model with only independent pulsar noises with a Bayes factor in excess of $10^{14}$, and this same model is favored over an uncorrelated common power-law-spectrum model with Baye","claim_type":"abstract","evidence_strength":"source_metadata"},{"claim_text":"sient catalogs GWTC-1 through GWTC-3 [2-4]. These observations have transformed gravitational-wave astron- omy into a precision discipline, enabling detailed tests of strong-field gravity and compact-object population stud- ies. In parallel, pulsar timing arrays, including NANOGrav, have recently reported evidence for a stochastic nanohertz gravitational-wave background [5], opening a complementary low-frequency window onto su- permassive black hole binaries and possible cosmological sources. Ev","claim_type":"background","confidence":0.95,"evidence_strength":"citation_context"},{"claim_text":"(PTAs) has provided strong evidence for a stochastic GW background [5-11]. With the fourth LIGO-Virgo- KAGRA observing run in progress and the continued PTA campaign [5, 7, 12, 13], more and more observa- tional data and, thus, scientific insight can be expected. While Earth-based detectors utilize interferometry to detect GWs, PTAs, including NANOGrav [7], the Euro- pean Pulsar Timing Array [8, 14], the Parkes Pulsar Tim- ing Array [9, 10, 12], the Chinese Pulsar Timing Array [11], and the Meer","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"ch § dschmitt@itp.uni-frankfurt.de [1] B. P. Abbott et al. (LIGO Scientific, Virgo), Phys. Rev. Lett. 116, 061102 (2016), arXiv:1602.03837 [gr-qc]. [2] G. Agazie et al. (NANOGrav), Astrophys. J. Lett. 951, L10 (2023), arXiv:2306.16218 [astro-ph.HE]. [3] G. Agazie et al. (NANOGrav), Astrophys. J. Lett. 951, L8 (2023), arXiv:2306.16213 [astro-ph.HE]. [4] G. Agazie et al. (NANOGrav), Astrophys. J. Lett. 951, L9 (2023), arXiv:2306.16217 [astro-ph.HE]. [5] G. Agazie et al. (NANOGrav), (2023), arXiv:2","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"Ever since the first detection of a gravitational wave event by LIGO [183], several large observatories are projected, e.g., LISA [184], Taiji [185], TianQin [185] and the Einstein Telescope [186]. In addi- tion to the detection of singular events, the gravitational wave background has also been recently detected by Pulsar Timing Array collaborations (e.g., NANOGrav, [187], CPTA [188], EPTA, [189]). Regarding FRBs, current radio observatories regularly detect these events, compiling ever-growing","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"be the detection of a stochastic primordial gravitational wave background, and the future gravitational wave experiments will operate in frequency bands that will probe the inflationary gravitational waves [6-14]. NANOGrav already verified a stochastic gravitational wave background back in 2023 [15], but inflation itself cannot generate such a signal [16, 17]. Thus the next ten years will be extremely important for modern theoretical physics. Recently, the Atacama Cosmology Telescope (ACT) [18, ","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"},{"claim_text":"turbation equations in certain higher-dimensional scenar - ios due to the influence of the bulk on the brane [55, 56]. Secondly, massive gravitons, either in explicit massive gravity theories or as effective degrees of freedom, have been argued to contribute to very long-wavelength grav- itational signals [57], which are currently being probed by Pulsar Timing Array experiments [58, 59]. Thirdly, massive fields may support arbitrarily long-lived QNMs for particular values of the field mass, leading ","claim_type":"background","confidence":0.9,"evidence_strength":"citation_context"}],"why_cited":"Pith tracks The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background because it crossed a citation-hub threshold. Current citing contexts most often use it as background evidence (27 contexts).","role_counts":[{"n":27,"context_role":"background"},{"n":3,"context_role":"dataset"},{"n":1,"context_role":"extension"},{"n":1,"context_role":"method"}]},"graph":{"co_cited":[{"title":"The second data release from the European Pulsar Timing Array III. Search for gravitational wave signals","work_id":"64aaf45a-ea75-497c-a5be-b1b7929567c1","shared_citers":52},{"title":"Search for an isotropic gravitational-wave background with the Parkes Pulsar Timing Array","work_id":"a701de45-9096-4e36-88b2-a80500e1c9ab","shared_citers":51},{"title":"Searching for the nano-Hertz stochastic gravitational wave background with the Chinese Pulsar Timing Array Data Release I","work_id":"026097ec-3d59-4324-957d-a33afc5b93d3","shared_citers":48},{"title":"The NANOGrav 15-year Data Set: Search for Signals from New Physics","work_id":"b174cd56-be02-4083-9bbc-7c59fc3b059b","shared_citers":33},{"title":"Observation of Gravitational Waves from a Binary Black Hole Merger","work_id":"ab878228-151c-4a29-8026-a4308b076d30","shared_citers":25},{"title":"Laser Interferometer Space Antenna","work_id":"04a25305-b4d4-47f9-9613-efea8cc0292b","shared_citers":22},{"title":"Planck 2018 results. VI. Cosmological parameters","work_id":"eeae0089-7b56-4c63-ace2-a31de468f6c5","shared_citers":22},{"title":"Cosmological Backgrounds of Gravitational Waves","work_id":"7d5d7ae0-6229-4c5f-9ce4-de6446b851f8","shared_citers":18},{"title":"Antoniadis et al","work_id":"2a060b09-7a5c-4887-b709-77c27476b25d","shared_citers":17},{"title":"Agazie et al","work_id":"f2d5a5d8-e2e1-43ee-a822-d2a50ad610c9","shared_citers":15},{"title":"Planck 2018 results. X. Constraints on inflation","work_id":"ac5d2133-b998-4b22-878d-b78fb5623e08","shared_citers":14},{"title":"The dataset and timing analysis,Astron","work_id":"593ddb23-1dd1-4d02-84f2-359c96c72d7a","shared_citers":14},{"title":"Detecting a stochastic background of gravitational radiation: Signal processing strategies and sensitivities","work_id":"4da2a6ff-2132-4f7e-9e26-2e34ea3139b6","shared_citers":13},{"title":"Gravitational wave astronomy with the SKA","work_id":"8e6e5d7c-f2b1-4ef3-9e89-5a61ddbfc0ad","shared_citers":13},{"title":"Science with the space-based interferometer eLISA. II: Gravitational waves from cosmological phase transitions","work_id":"1984496d-cfc6-46a3-953f-6b8aab5d502d","shared_citers":13},{"title":"The MeerKAT Pulsar Timing Array: The first search for gravitational waves with the MeerKAT radio telescope","work_id":"09981ee0-3f7d-406b-9161-1d84f3add128","shared_citers":13},{"title":"Unveiling the Gravitational Universe at \\mu-Hz Frequencies","work_id":"2837616c-6afa-4b5b-8f7d-e180aec020b4","shared_citers":13},{"title":"Agazie et al","work_id":"820ed646-deec-4f92-8272-0e57a1008392","shared_citers":12},{"title":"A Practical Theorem on Gravitational Wave Backgrounds","work_id":"db82e604-7d41-4806-994f-6620fd0543f3","shared_citers":12},{"title":"Zic et al.,The Parkes Pulsar Timing Array third data release,Publ","work_id":"69ae7569-0d42-40f0-b1d7-de00c17d1f49","shared_citers":12},{"title":"Agazie et al","work_id":"2f1fcd5f-e9b2-4649-a65d-8fe2236ed823","shared_citers":11},{"title":"TianQin: a space-borne gravitational wave detector","work_id":"6938d8d9-beb8-4a5e-ad7e-06e38d30620d","shared_citers":11},{"title":"Agazieet al.[International Pulsar Timing Array],Comparing recent PTA results on the nanohertz stochastic gravitational wave background,Astrophys","work_id":"9a4c3027-c074-4c91-bc50-4446b6b13549","shared_citers":10},{"title":"Auclair et al","work_id":"264d2696-4222-4047-a5f7-4d3ff5a2e546","shared_citers":10}],"time_series":[{"n":1,"year":2023},{"n":2,"year":2024},{"n":25,"year":2025},{"n":58,"year":2026}],"dependency_candidates":[{"n":1,"role":"dataset","polarity":"use_dataset","paper_title":"F-Term Hybrid Inflation with T-Model K\\\"ahler Geometry and Beyond","primary_cat":"hep-ph","context_text":"Theory(GUT) phase transition which may lead to the production of cosmological defects if predicted by the symmetry-breaking scheme - see e.g. Ref. [30]. Among them,Cosmic Strings(CSs) attract a fair amount of attention currently since they contribute to the CMB and generate [31] a stochastic back- ground ofgravitational waves(GWs) in the nanohertz range, probed bypulsar timing arrays(PT As) such asNANOGrav (15-yr)[32],EPTA[33],PPTA[34], andCPTA[35]. The tension of CSs is directly linked to the symmetry-breaking scale ofG, connecting ACT/SPT-preferred inflationary parameters with the spectrum of the GWs observed by PTAs - see, e.g., Ref. [15, 36-42]. For a reliable approach to FHI, soft SUSY-breaking terms [43-50] andSupergravity(SUGRA) cor- rections [51-55] have to be taken into account together with theradiative corrections(RCs) employed","citing_arxiv_id":"2605.08931"},{"n":1,"role":"method","polarity":"use_method","paper_title":"Imprint of domain wall annihilation on induced gravitational waves","primary_cat":"hep-ph","context_text":"annihilation and the onset of standard radiation domina- tion, bothΩpeak andf peak are modified. The peak ampli- tude is suppressed by the entropy dilution factor, while the peak frequency is redshifted according to the expan- sion history during and after the MD epoch. Incorporat- ing these modifications, we describe the GW spectrum using the broken power-law parametrization introduced 6 in Refs.[2, 105]: ΩGWh2 = Ωph2 D4/3 (a+b) c \u0012 b \u0010 D1/3 f fp \u0011−a/c +a \u0010 D1/3 f fp \u0011b/c\u0013c ,(36) wherea,bandcare real and positive parameters. Here the low-frequency slope4 a= 3can be fixed by causality, while numerical simulations suggestb≃c≃1[96]. InFig. 3, wefirstpresentthepower-lawintegratedsen- sitivity curves [106] of the future GW detectors ET [107], LISA [108], DECIGO [109],µAres [110], SKA [111], and","citing_arxiv_id":"2604.25726"},{"n":1,"role":"dataset","polarity":"use_dataset","paper_title":"Forecasting graviton-mass constraints from the full covariance of PTA-astrometry ORF estimators","primary_cat":"gr-qc","context_text":"containing the PTA, astrometric, and cross-channel observables. Using Hierarchical Equal Area isoLatitude Pixelation of a sphere (HEALPix) [51], we discretize the celestial sphere into a finite set of pixels, denoted byN pix. The fiducial model is the general-relativistic limit mg = 0 (ϵ= 0), with an injected power-law SGWB (A GWB, α) = (2.4×10 −15,−2/3) [14, 46]. At each discrete frequencyf k, we assemble the covariance matrix of the all-sky three- component signal field from the global-basis pairwise correlation subblocksC glob xy defined by Eqs. (12) and (13). In the present implementation, this signal covariance has dimension 3Npix ×3N pix, corresponding to one PTA-like observable and two astrometric deflection","citing_arxiv_id":"2604.23384"},{"n":1,"role":"dataset","polarity":"use_dataset","paper_title":"Purely Quadratic Non-Gaussianity from Tachyonic Instability: Primordial Black Holes and Scalar-Induced Gravitational Waves","primary_cat":"astro-ph.CO","context_text":"Thermal inflation provides a useful benchmark scenario with asteroid-mass PBH dark matter and high-frequency scalar-induced gravitational waves potentially detectable by future space-based interferometers, but its typically broad spectra make it challenging to reconcile PTA observations with PBH constraints. I. INTRODUCTION The recent pulsar timing array (PTA) data releases by the NANOGrav [1, 2], EPTA (in combination with InPTA) [3-5], PPTA [6-8], and CPTA [9] collaborations have reported compelling evidence for the existence of a stochas- tic gravitational wave background (SGWB) in the nanohertz (nHz) band. These measurements exhibit a statistical preference for the Hellings-Downs correlation among pulsar pairs, widely regarded as the hallmark signature of an","citing_arxiv_id":"2604.20063"},{"n":1,"role":"extension","polarity":"extend","paper_title":"The Heavy Tailed Non-Gaussianity of the Supermassive Black Hole Gravitational Wave Background","primary_cat":"astro-ph.CO","context_text":"ries, some of which may become individually resolvable as the PTA sensitivity improves [16-19]. The background is static because these binaries are far from coalescence, and their emission is nearly monochromatic, but exhibits significant anisotropies [20-23] and polarization [22, 24]. Furthermore, the distribution of realizations shows sub- stantial deviations from Gaussianity [10, 24-29]. These are characterized most conveniently by the SMBH GW amplitude distribution (GWAD). Building on our earlier results [10, 24], we confirm that the high-amplitude tail of GWAD exhibits auniversal, model-independent power-law scaling∝A −4 arising from the possibility of having nearby sources. This should be contrasted with an exponentially suppressed Gaus-","citing_arxiv_id":"2604.08506"}]},"authors":[{"id":"33c424ec-e0b0-4f5a-bf7a-82e12cee41ca","orcid":null,"display_name":"Akash Anumarlapudi","source":"manual","import_confidence":0.72},{"id":"cb0519c7-d1e5-4e62-ae84-b34690b9ded5","orcid":null,"display_name":"Anne M. Archibald","source":"manual","import_confidence":0.72},{"id":"49de92f4-60ec-4b7f-89fb-643f0c1dad79","orcid":null,"display_name":"Bence Becsy","source":"manual","import_confidence":0.72},{"id":"f52daf1a-bd4c-45af-880a-1fb397d30085","orcid":null,"display_name":"Gabriella Agazie","source":"manual","import_confidence":0.72},{"id":"8f003767-021e-4d9a-9358-4129ceedd91c","orcid":null,"display_name":"Paul T. Baker","source":"manual","import_confidence":0.72},{"id":"039b68ba-15b7-4c42-a1cf-4f07a0149ca9","orcid":null,"display_name":"Zaven Arzoumanian","source":"manual","import_confidence":0.72}]}}