All Outputs (72)

The NANOGrav 15 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries (2023)
Journal Article
Agazie, G., Anumarlapudi, A., Archibald, A. M., Arzoumanian, Z., Baker, P. T., Bécsy, B., …Young, O. (2023). The NANOGrav 15 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries. Astrophysical journal. Letters, 951(2), Article L50. https://doi.org/10.3847/2041-8213/ace18a

Evidence for a low-frequency stochastic gravitational-wave background has recently been reported based on analyses of pulsar timing array data. The most likely source of such a background is a population of supermassive black hole binaries, the loude... Read More about The NANOGrav 15 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries.

The NANOGrav 15 yr Data Set: Evidence for a Gravitational-wave Background (2023)
Journal Article
Agazie, G., Anumarlapudi, A., Archibald, A. M., Arzoumanian, Z., Baker, P. T., Bécsy, B., …Stovall, K. (2023). The NANOGrav 15 yr Data Set: Evidence for a Gravitational-wave Background. Astrophysical journal. Letters, 951(1), Article L8. https://doi.org/10.3847/2041-8213/acdac6

We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15 yr pulsar timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings... Read More about The NANOGrav 15 yr Data Set: Evidence for a Gravitational-wave Background.

The NANOGrav 15 yr Data Set: Observations and Timing of 68 Millisecond Pulsars (2023)
Journal Article
Agazie, G., Faisal Alam, M. F., Anumarlapudi, A., Archibald, A. M., Arzoumanian, Z., Baker, P. T., …NANOGrav Collaboration. (2023). The NANOGrav 15 yr Data Set: Observations and Timing of 68 Millisecond Pulsars. Astrophysical journal. Letters, 951(1), Article L9. https://doi.org/10.3847/2041-8213/acda9a

We present observations and timing analyses of 68 millisecond pulsars (MSPs) comprising the 15 yr data set of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav). NANOGrav is a pulsar timing array (PTA) experiment that is sens... Read More about The NANOGrav 15 yr Data Set: Observations and Timing of 68 Millisecond Pulsars.

The NANOGrav 15yr Data Set: Search for Signals from New Physics (2023)
Journal Article
Afzal, A., Agazie, G., Anumarlapudi, A., Archibald, A. M., Arzoumanian, Z., Baker, P. T., …Siemens, X. (2023). The NANOGrav 15yr Data Set: Search for Signals from New Physics. Astrophysical journal. Letters, 951(1), Article L11. https://doi.org/10.3847/2041-8213/acdc91

The 15 yr pulsar timing data set collected by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) shows positive evidence for the presence of a low-frequency gravitational-wave (GW) background. In this paper, we investigate po... Read More about The NANOGrav 15yr Data Set: Search for Signals from New Physics.

The NANOGrav 15 yr Data Set: Detector Characterization and Noise Budget (2023)
Journal Article
Agazie, G., Anumarlapudi, A., Archibald, A. M., Arzoumanian, Z., Baker, P. T., Bécsy, B., …Young, O. (2023). The NANOGrav 15 yr Data Set: Detector Characterization and Noise Budget. Astrophysical journal. Letters, 951(1), Article L10. https://doi.org/10.3847/2041-8213/acda88

Pulsar timing arrays (PTAs) are galactic-scale gravitational wave (GW) detectors. Each individual arm, composed of a millisecond pulsar, a radio telescope, and a kiloparsecs-long path, differs in its properties but, in aggregate, can be used to extra... Read More about The NANOGrav 15 yr Data Set: Detector Characterization and Noise Budget.

Variable scintillation arcs of millisecond pulsars observed with the Large European Array for Pulsars (2023)
Journal Article
Main, R. A., Antoniadis, J., Chen, S., Cognard, I., Hu, H., Jang, J., …Zhu, W. W. (2023). Variable scintillation arcs of millisecond pulsars observed with the Large European Array for Pulsars. Monthly notices of the Royal Astronomical Society, 525(1), 1079-1096. https://doi.org/10.1093/mnras/stad1980

We present the first large sample of scintillation arcs in millisecond pulsars (MSPs), analysing 12 sources observed with the Large European Array for Pulsars (LEAP), and the Effelsberg 100-m telescope. We estimate the delays from multipath propagati... Read More about Variable scintillation arcs of millisecond pulsars observed with the Large European Array for Pulsars.

Searching for continuous Gravitational Waves in the second data release of the International Pulsar Timing Array (2023)
Journal Article
Falxa, M., Babak, S., Baker, P. T., Bécsy, B., Chalumeau, A., Chen, S., …Collaboration, I. (2023). Searching for continuous Gravitational Waves in the second data release of the International Pulsar Timing Array. Monthly notices of the Royal Astronomical Society, 521(4), 5077-5086. https://doi.org/10.1093/mnras/stad812

The International Pulsar Timing Array 2nd data release is the combination of data sets from worldwide collaborations. In this study, we search for continuous waves: gravitational wave signals produced by individual supermassive black hole binaries in... Read More about Searching for continuous Gravitational Waves in the second data release of the International Pulsar Timing Array.

Pulsar scintillation studies with LOFAR: II. Dual-frequency scattering study of PSR J0826+2637 with LOFAR and NenuFAR (2023)
Journal Article
Wu, Z., Coles, W. A., Verbiest, J. P., Ambalappat, K. M., Tiburzi, C., Grießmeier, J. M., …Corbel, S. (2023). Pulsar scintillation studies with LOFAR: II. Dual-frequency scattering study of PSR J0826+2637 with LOFAR and NenuFAR. Monthly notices of the Royal Astronomical Society, 520(4), 5536-5543. https://doi.org/10.1093/mnras/stad429

Interstellar scattering (ISS) of radio pulsar emission can be used as a probe of the ionized interstellar medium (IISM) and causes corruptions in pulsar timing experiments. Two types of ISS phenomena (intensity scintillation and pulse broadening) are... Read More about Pulsar scintillation studies with LOFAR: II. Dual-frequency scattering study of PSR J0826+2637 with LOFAR and NenuFAR.

CHIME Discovery of a Binary Pulsar with a Massive Nondegenerate Companion (2023)
Journal Article
Andersen, B. C., Fonseca, E., McKee, J. W., Meyers, B. W., Luo, J., Tan, C. M., …Tendulkar, S. P. (2023). CHIME Discovery of a Binary Pulsar with a Massive Nondegenerate Companion. The Astrophysical journal, 943(1), Article 57. https://doi.org/10.3847/1538-4357/aca485

Of the more than 3000 radio pulsars currently known, only ∼300 are in binary systems, and only five of these consist of young pulsars with massive nondegenerate companions. We present the discovery and initial timing, accomplished using the Canadian... Read More about CHIME Discovery of a Binary Pulsar with a Massive Nondegenerate Companion.

Scattering variability detected from the circumsource medium of FRB 20190520B (2022)
Journal Article
Ocker, S. K., Cordes, J. M., Chatterjee, S., Li, D., Niu, C. H., Mckee, J. W., …Anna-Thomas, R. (2023). Scattering variability detected from the circumsource medium of FRB 20190520B. Monthly notices of the Royal Astronomical Society, 519(1), 821-830. https://doi.org/10.1093/mnras/stac3547

Fast radio bursts (FRBs) are millisecond-time-scale radio transients, the origins of which are predominantly extragalactic and likely involve highly magnetized compact objects. FRBs undergo multipath propagation, or scattering, from electron density... Read More about Scattering variability detected from the circumsource medium of FRB 20190520B.

Robust parameter estimation from pulsar timing data (2022)
Journal Article
Samajdar, A., Shaifullah, G. M., Sesana, A., Antoniadis, J., Burgay, M., Chen, S., …Van Der Wateren, E. (2022). Robust parameter estimation from pulsar timing data. Monthly notices of the Royal Astronomical Society, 517(1), 1460-1468. https://doi.org/10.1093/mnras/stac2810

Recently, global pulsar timing arrays have released results from searching for a nano-Hertz gravitational wave background signal. Although there has not been any definite evidence of the presence of such a signal in residuals of pulsar timing data ye... Read More about Robust parameter estimation from pulsar timing data.

Long-term scintillation studies of EPTA pulsars I. Observations and basic results (2022)
Journal Article
Liu, Y., Verbiest, J. P., Main, R. A., Wu, Z., Ambalappat, K. M., Champion, D. J., …Theureau, G. (2022). Long-term scintillation studies of EPTA pulsars I. Observations and basic results. Astronomy and Astrophysics, 664, Article A116. https://doi.org/10.1051/0004-6361/202142552

Context. Interstellar scintillation analysis of pulsars allows us to probe the small-scale distribution and inhomogeneities of the ionized interstellar medium. From the frequency scale of scintillation, one can estimate the geometric time delays from... Read More about Long-term scintillation studies of EPTA pulsars I. Observations and basic results.

Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run (2022)
Journal Article
Abbott, R., Abbott, T. D., Acernese, F., Ackley, K., Adams, C., Adhikari, N., …McKee, J. (2022). Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run. The Astrophysical journal, 932(2), Article 133. https://doi.org/10.3847/1538-4357/ac6ad0

Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Vir... Read More about Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run.

The Large Dispersion and Scattering of FRB 20190520B Are Dominated by the Host Galaxy (2022)
Journal Article
Koch Ocker, S., Cordes, J. M., Chatterjee, S., Niu, C. H., Li, D., McKee, J. W., …Cruces, M. (2022). The Large Dispersion and Scattering of FRB 20190520B Are Dominated by the Host Galaxy. The Astrophysical journal, 931(2), Article 87. https://doi.org/10.3847/1538-4357/ac6504

The repeating fast radio burst FRB 20190520B is localized to a galaxy at z = 0.241, much closer than expected given its dispersion measure DM = 1205 ± 4 pc cm-3. Here we assess implications of the large DM and scattering observed from FRB 20190520B f... Read More about The Large Dispersion and Scattering of FRB 20190520B Are Dominated by the Host Galaxy.

Searches for Gravitational Waves from Known Pulsars at Two Harmonics in the Second and Third LIGO-Virgo Observing Runs (2022)
Journal Article
Abbott, R., Abe, H., Acernese, F., Ackley, K., Adhikari, N., Adhikari, R., …Weltevrede, P. (2022). Searches for Gravitational Waves from Known Pulsars at Two Harmonics in the Second and Third LIGO-Virgo Observing Runs. The Astrophysical journal, 935(1), Article 1. https://doi.org/10.3847/1538-4357/ac6acf

We present a targeted search for continuous gravitational waves (GWs) from 236 pulsars using data from the third observing run of LIGO and Virgo (O3) combined with data from the second observing run (O2). Searches were for emission from the l = m = 2... Read More about Searches for Gravitational Waves from Known Pulsars at Two Harmonics in the Second and Third LIGO-Virgo Observing Runs.

Detection of quasi-periodic micro-structure in three millisecond pulsars with the Large European Array for Pulsars (2022)
Journal Article
Liu, K., Antoniadis, J., Bassa, C. G., Chen, S., Cognard, I., Gaikwad, M., …Possenti, A. (2022). Detection of quasi-periodic micro-structure in three millisecond pulsars with the Large European Array for Pulsars. Monthly notices of the Royal Astronomical Society, 513(3), 4037-4044. https://doi.org/10.1093/mnras/stac1082

We report on the detection of quasi-periodic micro-structure in three millisecond pulsars (MSPs), PSRs J1022+1001, J2145-0750, and J1744-1134, using high time resolution data acquired with the Large European Array for Pulsars at a radio frequency of... Read More about Detection of quasi-periodic micro-structure in three millisecond pulsars with the Large European Array for Pulsars.

Probing the Local Interstellar Medium with Scintillometry of the Bright Pulsar B1133 + 16 (2022)
Journal Article
McKee, J. W., Zhu, H., Stinebring, D. R., & Cordes, J. M. (2022). Probing the Local Interstellar Medium with Scintillometry of the Bright Pulsar B1133 + 16. The Astrophysical journal, 927(1), Article 99. https://doi.org/10.3847/1538-4357/ac460b

The interstellar medium hosts a population of scattering screens, most of unknown origin. Scintillation studies of pulsars provide a sensitive tool for resolving these scattering screens and a means of measuring their properties. In this paper, we re... Read More about Probing the Local Interstellar Medium with Scintillometry of the Bright Pulsar B1133 + 16.

Dual-frequency single-pulse study of PSR B0950+08 (2022)
Journal Article
Bilous, A. V., Grießmeier, J. M., Pennucci, T., Wu, Z., Bondonneau, L., Kondratiev, V., …Ziemke, J. (2022). Dual-frequency single-pulse study of PSR B0950+08. Astronomy and Astrophysics, 658, Article A143. https://doi.org/10.1051/0004-6361/202142242

PSR B0950+08 is a bright nonrecycled pulsar whose single-pulse fluence variability is reportedly large. Based on observations at two widely separated frequencies, 55 MHz (NenuFAR) and 1.4 GHz (Westerbork Synthesis Radio Telescope), we review the prop... Read More about Dual-frequency single-pulse study of PSR B0950+08.

The International Pulsar Timing Array second data release: Search for an isotropic gravitational wave background (2022)
Journal Article
Antoniadis, J., Arzoumanian, Z., Babak, S., Bailes, M., Bak Nielsen, A. S., Baker, P. T., …Shaifullah, G. (2022). The International Pulsar Timing Array second data release: Search for an isotropic gravitational wave background. Monthly notices of the Royal Astronomical Society, 510(4), 4873-4887. https://doi.org/10.1093/mnras/stab3418

We searched for an isotropic stochastic gravitational wave background in the second data release of the International Pulsar Timing Array, a global collaboration synthesizing decadal-length pulsar-timing campaigns in North America, Europe, and Austra... Read More about The International Pulsar Timing Array second data release: Search for an isotropic gravitational wave background.

Modelling annual scintillation arc variations in PSR J1643-1224 using the Large European Array for Pulsars (2022)
Journal Article
Mall, G., Main, R. A., Antoniadis, J., Bassa, C. G., Burgay, M., Chen, S., …Zhu, W. W. (2022). Modelling annual scintillation arc variations in PSR J1643-1224 using the Large European Array for Pulsars. Monthly notices of the Royal Astronomical Society, 511(1), 1104-1114. https://doi.org/10.1093/mnras/stac096

In this work, we study variations in the parabolic scintillation arcs of the binary millisecond pulsar PSR J1643-1224 over five years using the Large European Array for Pulsars (LEAP). The two-dimensional (2D) power spectrum of scintillation, called... Read More about Modelling annual scintillation arc variations in PSR J1643-1224 using the Large European Array for Pulsars.