All Outputs (76)

Modeling nonstationary noise in pulsar timing array data analysis (2024)
Journal Article
Falxa, M., Antoniadis, J., Champion, D. J., Cognard, I., Desvignes, G., Guillemot, L., Hu, H., Janssen, G., Jawor, J., Karuppusamy, R., Keith, M., Kramer, M., Lackeos, K., Liu, K., McKee, J. W., Perrodin, D., Sanidas, S., Shaifullah, G., & Theureau, G. (2024). Modeling nonstationary noise in pulsar timing array data analysis. Physical Review D, 109(12), Article 123010. https://doi.org/10.1103/PhysRevD.109.123010

Pulsar timing array (PTA) collaborations recently reported evidence for the presence of a gravitational wave background (GWB) in their datasets. The main candidate that is expected to produce such a GWB is the population of supermassive black hole bi... Read More about Modeling nonstationary noise in pulsar timing array data analysis.

A new pulsar timing model for scalar-tensor gravity with applications to PSR J2222-0137 and pulsar-black hole binaries (2024)
Journal Article
Batrakov, A., Hu, H., Wex, N., Freire, P. C., Venkatraman Krishnan, V., Kramer, M., …Theureau, G. (2024). A new pulsar timing model for scalar-tensor gravity with applications to PSR J2222-0137 and pulsar-black hole binaries. Astronomy and Astrophysics, 686(June), Article A101. https://doi.org/10.1051/0004-6361/202245246

Context. Scalar-tensor gravity (STG) theories are well-motivated alternatives to general relativity (GR). One class of STG theories, Damour- Esposito- Farèse (DEF) gravity, has a massless scalar field with two arbitrary coupling parameters. We are in... Read More about A new pulsar timing model for scalar-tensor gravity with applications to PSR J2222-0137 and pulsar-black hole binaries.

NANOGrav 15-year gravitational-wave background methods (2024)
Journal Article
Johnson, A. D., Meyers, P. M., Baker, P. T., Cornish, N. J., Hazboun, J. S., Littenberg, T. B., …Young, O. (2024). NANOGrav 15-year gravitational-wave background methods. Physical Review D, 109(10), Article 103012. https://doi.org/10.1103/PhysRevD.109.103012

Pulsar timing arrays (PTAs) use an array of millisecond pulsars to search for gravitational waves in the nanohertz regime in pulse time of arrival data. This paper presents rigorous tests of PTA methods, examining their consistency across the relevan... Read More about NANOGrav 15-year gravitational-wave background methods.

The second data release from the European Pulsar Timing Array: IV. Implications for massive black holes, dark matter, and the early Universe (2024)
Journal Article
EPTA Collaboration and InPTA Collaboration, Antoniadis, J., Arumugam, P., Arumugam, S., Babak, S., Bagchi, M., …Valtolina, S. (2024). The second data release from the European Pulsar Timing Array: IV. Implications for massive black holes, dark matter, and the early Universe. Astronomy and Astrophysics, 685, Article A94. https://doi.org/10.1051/0004-6361/202347433

The European Pulsar Timing Array (EPTA) and Indian Pulsar Timing Array (InPTA) collaborations have measured a low-frequency common signal in the combination of their second and first data releases, respectively, with the correlation properties of a g... Read More about The second data release from the European Pulsar Timing Array: IV. Implications for massive black holes, dark matter, and the early Universe.

Comparing Recent Pulsar Timing Array Results on the Nanohertz Stochastic Gravitational-wave Background (2024)
Journal Article
Agazie, G., Antoniadis, J., Anumarlapudi, A., Archibald, A. M., Arumugam, P., Arumugam, S., …The International Pulsar Timing Array Collaboration. (2024). Comparing Recent Pulsar Timing Array Results on the Nanohertz Stochastic Gravitational-wave Background. The Astrophysical journal, 966(1), Article 105. https://doi.org/10.3847/1538-4357/ad36be

The Australian, Chinese, European, Indian, and North American pulsar timing array (PTA) collaborations recently reported, at varying levels, evidence for the presence of a nanohertz gravitational-wave background (GWB). Given that each PTA made differ... Read More about Comparing Recent Pulsar Timing Array Results on the Nanohertz Stochastic Gravitational-wave Background.

High-cadence Timing of Binary Pulsars with CHIME (2024)
Journal Article
Tan, C. M., Fonseca, E., Crowter, K., Dong, F. A., Kaspi, V. M., Masui, K. W., …Stairs, I. H. (2024). High-cadence Timing of Binary Pulsars with CHIME. The Astrophysical journal, 966(1), Article 26. https://doi.org/10.3847/1538-4357/ad28b2

We performed near-daily observations of the binary pulsars PSR J0218+4232, PSR J1518+4904, and PSR J2023+2853 with the Canadian Hydrogen Intensity Mapping Experiment (CHIME). For the first time, we detected the Shapiro time delay in all three pulsar... Read More about High-cadence Timing of Binary Pulsars with CHIME.

An Unusual Pulse Shape Change Event in PSR J1713+0747 Observed with the Green Bank Telescope and CHIME (2024)
Journal Article
Jennings, R. J., Cordes, J. M., Chatterjee, S., McLaughlin, M. A., Demorest, P. B., Arzoumanian, Z., …Witt, C. A. (2024). An Unusual Pulse Shape Change Event in PSR J1713+0747 Observed with the Green Bank Telescope and CHIME. The Astrophysical journal, 964(2), Article 179. https://doi.org/10.3847/1538-4357/ad2930

The millisecond pulsar J1713+0747 underwent a sudden and significant pulse shape change between 2021 April 16 and 17 (MJDs 59320 and 59321). Subsequently, the pulse shape gradually recovered over the course of several months. We report the results of... Read More about An Unusual Pulse Shape Change Event in PSR J1713+0747 Observed with the Green Bank Telescope and CHIME.

The NANOGrav 15 yr Data Set: Search for Transverse Polarization Modes in the Gravitational-wave Background (2024)
Journal Article
Agazie, G., Anumarlapudi, A., Archibald, A. M., Arzoumanian, Z., Baier, J., Baker, P. T., …The NANOGrav Collaboration. (2024). The NANOGrav 15 yr Data Set: Search for Transverse Polarization Modes in the Gravitational-wave Background. Astrophysical journal. Letters, 964(1), L14. https://doi.org/10.3847/2041-8213/ad2a51

Recently we found compelling evidence for a gravitational-wave background with Hellings and Downs (HD) correlations in our 15 yr data set. These correlations describe gravitational waves as predicted by general relativity, which has two transverse po... Read More about The NANOGrav 15 yr Data Set: Search for Transverse Polarization Modes in the Gravitational-wave Background.

The NANOGrav 12.5 yr Data Set: A Computationally Efficient Eccentric Binary Search Pipeline and Constraints on an Eccentric Supermassive Binary Candidate in 3C 66B (2024)
Journal Article
Agazie, G., Arzoumanian, Z., Baker, P. T., Bécsy, B., Blecha, L., Blumer, H., …The NANOGrav Collaboration. (2024). The NANOGrav 12.5 yr Data Set: A Computationally Efficient Eccentric Binary Search Pipeline and Constraints on an Eccentric Supermassive Binary Candidate in 3C 66B. The Astrophysical journal, 963(2), 144. https://doi.org/10.3847/1538-4357/ad1f61

The radio galaxy 3C 66B has been hypothesized to host a supermassive black hole binary (SMBHB) at its center based on electromagnetic observations. Its apparent 1.05 yr period and low redshift (∼0.02) make it an interesting testbed to search for low-... Read More about The NANOGrav 12.5 yr Data Set: A Computationally Efficient Eccentric Binary Search Pipeline and Constraints on an Eccentric Supermassive Binary Candidate in 3C 66B.

The NANOGrav 12.5 yr Data Set: Search for Gravitational Wave Memory (2024)
Journal Article
Agazie, G., Arzoumanian, Z., Baker, P. T., Bécsy, B., Blecha, L., Blumer, H., …The NANOGrav Collaboration. (2024). The NANOGrav 12.5 yr Data Set: Search for Gravitational Wave Memory. The Astrophysical journal, 963(1), Article 61. https://doi.org/10.3847/1538-4357/ad0726

We present the results of a Bayesian search for gravitational wave (GW) memory in the NANOGrav 12.5 yr data set. We find no convincing evidence for any gravitational wave memory signals in this data set. We find a Bayes factor of 2.8 in favor of a mo... Read More about The NANOGrav 12.5 yr Data Set: Search for Gravitational Wave Memory.

The Green Bank North Celestial Cap Survey. IX. Timing Follow-up for 128 Pulsars (2024)
Journal Article
McEwen, A. E., Swiggum, J. K., Kaplan, D. L., Tan, C. M., Meyers, B. W., Fonseca, E., …Stairs, I. H. (2024). The Green Bank North Celestial Cap Survey. IX. Timing Follow-up for 128 Pulsars. The Astrophysical journal, 962(2), Article 167. https://doi.org/10.3847/1538-4357/ad11f0

The Green Bank North Celestial Cap survey is one of the largest and most sensitive searches for pulsars and transient radio objects. Observations for the survey have finished; priorities have shifted toward long-term monitoring of its discoveries. In... Read More about The Green Bank North Celestial Cap Survey. IX. Timing Follow-up for 128 Pulsars.

A Gaussian-processes approach to fitting for time-variable spherical solar wind in pulsar timing data (2024)
Journal Article
Niţu, I. C., Keith, M. J., Tiburzi, C., Brüggen, M., Champion, D. J., Chen, S., …Vocks, C. (2024). A Gaussian-processes approach to fitting for time-variable spherical solar wind in pulsar timing data. Monthly notices of the Royal Astronomical Society, 528(2), 3304-3319. https://doi.org/10.1093/mnras/stae220

Propagation effects are one of the main sources of noise in high-precision pulsar timing. For pulsars below an ecliptic latitude of 5◦, the ionized plasma in the solar wind can introduce dispersive delays of order 100 μs around solar conjunction at a... Read More about A Gaussian-processes approach to fitting for time-variable spherical solar wind in pulsar timing data.

Practical approaches to analyzing PTA data: Cosmic strings with six pulsars (2023)
Journal Article
Quelquejay Leclere, H., Auclair, P., Babak, S., Chalumeau, A., Steer, D. A., Antoniadis, J., …Wu, Z. (2023). Practical approaches to analyzing PTA data: Cosmic strings with six pulsars. Physical Review D, 108(12), Article 123527. https://doi.org/10.1103/PhysRevD.108.123527

We search for a stochastic gravitational wave background (SGWB) generated by a network of cosmic strings using six millisecond pulsars from Data Release 2 (DR2) of the European Pulsar Timing Array (EPTA). We perform a Bayesian analysis considering tw... Read More about Practical approaches to analyzing PTA data: Cosmic strings with six pulsars.

Search for gravitational wave signals from known pulsars in LIGO-Virgo O3 data using the 5n -vector ensemble method (2023)
Journal Article
D'Onofrio, L., De Rosa, R., Palomba, C., Leaci, P., Piccinni, O. J., Sequino, V., …Stappers, B. (2023). Search for gravitational wave signals from known pulsars in LIGO-Virgo O3 data using the 5n -vector ensemble method. Physical Review D, 108(12), Article 122002. https://doi.org/10.1103/PhysRevD.108.122002

The 5n-vector ensemble method is a multiple test for the targeted search of continuous gravitational waves from an ensemble of known pulsars. This method can improve the detection probability by combining the results from individually undetectable pu... Read More about Search for gravitational wave signals from known pulsars in LIGO-Virgo O3 data using the 5n -vector ensemble method.

Constraining the magnetic field geometry of the millisecond pulsar PSRJ0030+0451 from joint radio, thermal X-ray, and γ-ray emission (2023)
Journal Article
Pétri, J., Guillot, S., Guillemot, L., Cognard, I., Theureau, G., Grießmeier, J. M., …Zarka, P. (2023). Constraining the magnetic field geometry of the millisecond pulsar PSRJ0030+0451 from joint radio, thermal X-ray, and γ-ray emission. Astronomy and Astrophysics, 680, Article A93. https://doi.org/10.1051/0004-6361/202346913

Context. With the advent of multi-wavelength electromagnetic observations of neutron stars - spanning many decades in photon energies - from radio wavelengths up to X-rays and γ-rays, it has become possible to significantly constrain the geometry and... Read More about Constraining the magnetic field geometry of the millisecond pulsar PSRJ0030+0451 from joint radio, thermal X-ray, and γ-ray emission.

Pulsar scintillation through thick and thin: bow shocks, bubbles, and the broader interstellar medium (2023)
Journal Article
Ocker, S. K., Cordes, J. M., Chatterjee, S., Stinebring, D. R., Dolch, T., Giannakopoulos, C., …Reardon, D. J. (2024). Pulsar scintillation through thick and thin: bow shocks, bubbles, and the broader interstellar medium. Monthly notices of the Royal Astronomical Society, 527(3), 7568-7587. https://doi.org/10.1093/mnras/stad3683

Observations of pulsar scintillation are among the few astrophysical probes of very small-scale ( au) phenomena in the interstellar medium (ISM). In particular, characterization of scintillation arcs, including their curvature and intensity distribut... Read More about Pulsar scintillation through thick and thin: bow shocks, bubbles, and the broader interstellar medium.

How to Detect an Astrophysical Nanohertz Gravitational Wave Background (2023)
Journal Article
Bécsy, B., Cornish, N. J., Meyers, P. M., Kelley, L. Z., Agazie, G., Anumarlapudi, A., …Young, O. (2023). How to Detect an Astrophysical Nanohertz Gravitational Wave Background. The Astrophysical journal, 959(1), Article 9. https://doi.org/10.3847/1538-4357/ad09e4

Analyses of pulsar timing data have provided evidence for a stochastic gravitational wave background in the nanohertz frequency band. The most plausible source of this background is the superposition of signals from millions of supermassive black hol... Read More about How to Detect an Astrophysical Nanohertz Gravitational Wave Background.

The black widow pulsar J1641+8049 in the optical, radio, and X-rays (2023)
Journal Article
Kirichenko, A. Y., Zharikov, S. V., Karpova, A. V., Fonseca, E., Zyuzin, D. A., Shibanov, Y. A., …Swiggum, J. K. (2024). The black widow pulsar J1641+8049 in the optical, radio, and X-rays. Monthly notices of the Royal Astronomical Society, 527(3), 4563-4572. https://doi.org/10.1093/mnras/stad3391

PSR J1641+8049 is a 2 ms black widow pulsar with the 2.2 h orbital period detected in the radio and γ -rays. We performed new phase-resolved multiband photometry of PSR J1641+8049 using the OSIRIS instrument at the Gran Telescopio Canarias. The obtai... Read More about The black widow pulsar J1641+8049 in the optical, radio, and X-rays.

Second Data Release from the European Pulsar Timing Array: Challenging the Ultralight Dark Matter Paradigm (2023)
Journal Article
Smarra, C., Goncharov, B., Barausse, E., Antoniadis, J., Babak, S., Bak Nielsen, A.-S., …European Pulsar Timing Array. (2023). Second Data Release from the European Pulsar Timing Array: Challenging the Ultralight Dark Matter Paradigm. Physical review letters, 131(17), Article 171001. https://doi.org/10.1103/PhysRevLett.131.171001

Pulsar Timing Array experiments probe the presence of possible scalar or pseudoscalar ultralight dark matter particles through decade-long timing of an ensemble of galactic millisecond radio pulsars. With the second data release of the European Pulsa... Read More about Second Data Release from the European Pulsar Timing Array: Challenging the Ultralight Dark Matter Paradigm.

The NANOGrav 15 yr Data Set: Search for Anisotropy in the Gravitational-wave Background (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: Search for Anisotropy in the Gravitational-wave Background. Astrophysical journal. Letters, 956(1), Article L3. https://doi.org/10.3847/2041-8213/acf4fd

The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has reported evidence for the presence of an isotropic nanohertz gravitational-wave background (GWB) in its 15 yr data set. However, if the GWB is produced by a population of... Read More about The NANOGrav 15 yr Data Set: Search for Anisotropy in the Gravitational-wave Background.