All Outputs (12)

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.