Skip to main content

Research Repository

Advanced Search

All Outputs (99)

The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry (2022)
Journal Article
Richings, A. J., Faucher-Giguère, C. A., Gurvich, A. B., Schaye, J., & Hayward, C. C. (2022). The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry. Monthly notices of the Royal Astronomical Society, 517(2), 1557-1583. https://doi.org/10.1093/mnras/stac2338

Interstellar chemistry is important for galaxy formation, as it determines the rate at which gas can cool, and enables us to make predictions for observable spectroscopic lines from ions and molecules. We explore two central aspects of modelling the... Read More about The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry.

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.

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.

A theoretical analysis of the scale separation in a model to predict solid tumour growth (2022)
Journal Article
de Melo Quintela, B., Hervas-Raluy, S., Garcia-Aznar, J. M., Walker, D., Wertheim, K. Y., & Viceconti, M. (2022). A theoretical analysis of the scale separation in a model to predict solid tumour growth. Journal of Theoretical Biology, 547, Article 111173. https://doi.org/10.1016/j.jtbi.2022.111173

Solid tumour growth depends on a host of factors which affect the cell life cycle and extracellular matrix vascularization that leads to a favourable environment. The whole solid tumour can either grow or wither in response to the action of the immun... Read More about A theoretical analysis of the scale separation in a model to predict solid tumour growth.

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.

Resilience of sloshing cold fronts against subsequent minor mergers (2022)
Journal Article
Vaezzadeh, I., Roediger, E., Cashmore, C., Hunt, M., Zuhone, J., Forman, W., …Churazov, E. (2022). Resilience of sloshing cold fronts against subsequent minor mergers. Monthly notices of the Royal Astronomical Society, 514(1), 518-534. https://doi.org/10.1093/mnras/stac784

Minor mergers are common in galaxy clusters. They have the potential to create sloshing cold fronts (SCFs) in the intracluster medium of the cluster. However, the resilience of SCFs to subsequent minor mergers is unknown. Here we investigate the exte... Read More about Resilience of sloshing cold fronts against subsequent minor mergers.

Galaxy And Mass Assembly (GAMA): Data Release 4 and the z < 0.1 total and z < 0.08 morphological galaxy stellar mass functions (2022)
Journal Article
Driver, S. P., Bellstedt, S., Robotham, A. S. G., Baldry, I. K., Davies, L. J., Liske, J., …Wilkins, S. M. (2022). Galaxy And Mass Assembly (GAMA): Data Release 4 and the z < 0.1 total and z < 0.08 morphological galaxy stellar mass functions. Monthly notices of the Royal Astronomical Society, 513(1), 439-467. https://doi.org/10.1093/mnras/stac472

In Galaxy And Mass Assembly Data Release 4 (GAMA DR4), we make available our full spectroscopic redshift sample. This includes 248 682 galaxy spectra, and, in combination with earlier surveys, results in 330 542 redshifts across five sky regions cove... Read More about Galaxy And Mass Assembly (GAMA): Data Release 4 and the z < 0.1 total and z < 0.08 morphological galaxy stellar mass functions.

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.

Lexicon-Based Sentiment Analysis and Emotion Classification of Climate Change Related Tweets (2022)
Presentation / Conference Contribution
Fagbola, T. M., Abayomi, A., Mutanga, M. B., & Jugoo, V. (2022). Lexicon-Based Sentiment Analysis and Emotion Classification of Climate Change Related Tweets. In Proceedings of the 13th International Conference on Soft Computing and Pattern Recognition (SoCPaR 2021) (637-646). https://doi.org/10.1007/978-3-030-96302-6_60

The concerns for a potential future climate jeopardy has steered actions by youths globally to call the governments to immediately address challenges relating to climate change. In this paper, using natural language processing techniques in data scie... Read More about Lexicon-Based Sentiment Analysis and Emotion Classification of Climate Change Related Tweets.

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.

Localizing FRBs through VLBI with the Algonquin Radio Observatory 10 m Telescope (2022)
Journal Article
Cassanelli, T., Leung, C., Rahman, M., Vanderlinde, K., Mena-Parra, J., Cary, S., …Tendulkar, S. P. (2022). Localizing FRBs through VLBI with the Algonquin Radio Observatory 10 m Telescope. Astronomical Journal, 163(2), Article 65. https://doi.org/10.3847/1538-3881/ac3d2f

The Canadian Hydrogen Intensity Mapping Experiment (CHIME)/FRB experiment has detected thousands of fast radio bursts (FRBs) due to its sensitivity and wide field of view; however, its low angular resolution prevents it from localizing events to thei... Read More about Localizing FRBs through VLBI with the Algonquin Radio Observatory 10 m Telescope.

Study of 72 Pulsars Discovered in the PALFA Survey: Timing Analysis, Glitch Activity, Emission Variability, and a Pulsar in an Eccentric Binary (2022)
Journal Article
Parent, E., Sewalls, H., Freire, P. C., Matheny, T., Lyne, A. G., Perera, B. B., …Zhu, W. W. (2022). Study of 72 Pulsars Discovered in the PALFA Survey: Timing Analysis, Glitch Activity, Emission Variability, and a Pulsar in an Eccentric Binary. The Astrophysical journal, 924(2), Article 135. https://doi.org/10.3847/1538-4357/ac375d

We present new discoveries and results from long-term timing of 72 pulsars discovered in the Pulsar Arecibo L-band Feed Array (PALFA) survey, including precise determination of astrometric and spin parameters, and flux density and scatter broadening... Read More about Study of 72 Pulsars Discovered in the PALFA Survey: Timing Analysis, Glitch Activity, Emission Variability, and a Pulsar in an Eccentric Binary.

Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: inferences in the stochastic gravitational-wave background search (2021)
Journal Article
Chen, S., Caballero, R. N., Guo, Y. J., Chalumeau, A., Liu, K., Shaifullah, G., …Xu, H. (2021). Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: inferences in the stochastic gravitational-wave background search. Monthly notices of the Royal Astronomical Society, 508(4), 4970-4993. https://doi.org/10.1093/mnras/stab2833

We present results from the search for a stochastic gravitational-wave background (GWB) as predicted by the theory of General Relativity using six radio millisecond pulsars from the Data Release 2 (DR2) of the European Pulsar Timing Array (EPTA) cove... Read More about Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: inferences in the stochastic gravitational-wave background search.

Removal and replacement of interference in tied-array radio pulsar observations using the spectral kurtosis estimator (2021)
Journal Article
Purver, M., Bassa, C. G., Cognard, I., Janssen, G. H., Karuppusamy, R., Kramer, M., …Stappers, B. W. (2022). Removal and replacement of interference in tied-array radio pulsar observations using the spectral kurtosis estimator. Monthly notices of the Royal Astronomical Society, 510(2), 1597-1611. https://doi.org/10.1093/mnras/stab3434

We describe how to implement the spectral kurtosis method of interference removal (zapping) on a digitized signal of averaged power values. Spectral kurtosis is a hypothesis test, analogous to the t-test, with a null hypothesis that the amplitudes fr... Read More about Removal and replacement of interference in tied-array radio pulsar observations using the spectral kurtosis estimator.

Noise analysis in the European Pulsar Timing Array data release 2 and its implications on the gravitational-wave background search (2021)
Journal Article
Chalumeau, A., Babak, S., Petiteau, A., Chen, S., Samajdar, A., Caballero, R. N., …Xu, H. (2022). Noise analysis in the European Pulsar Timing Array data release 2 and its implications on the gravitational-wave background search. Monthly notices of the Royal Astronomical Society, 509(4), 5538-5558. https://doi.org/10.1093/mnras/stab3283

The European Pulsar Timing Array (EPTA) collaboration has recently released an extended data set for six pulsars (DR2) and reported evidence for a common red noise signal. Here we present a noise analysis for each of the six pulsars. We consider seve... Read More about Noise analysis in the European Pulsar Timing Array data release 2 and its implications on the gravitational-wave background search.

PSR J2222-0137: I. Improved physical parameters for the system (2021)
Journal Article
Guo, Y. J., Freire, P. C., Guillemot, L., Kramer, M., Zhu, W. W., Wex, N., …Theureau, G. (2021). PSR J2222-0137: I. Improved physical parameters for the system. Astronomy and Astrophysics, 654, Article A16. https://doi.org/10.1051/0004-6361/202141450

Context. The PSR J2222-0137 binary system has a set of features that make it a unique laboratory for tests of gravity theories. Aims. To fully exploit the system's potential for these tests, we aim to improve the measurements of its physical paramete... Read More about PSR J2222-0137: I. Improved physical parameters for the system.

Strong-field gravity tests with the double pulsar (2021)
Journal Article
Kramer, M., Stairs, I. H., Manchester, R. N., Wex, N., Deller, A. T., Coles, W. A., …Theureau, G. (2021). Strong-field gravity tests with the double pulsar. Physical Review X, 11(4), Article 041050. https://doi.org/10.1103/PhysRevX.11.041050

Continued timing observations of the double pulsar PSR J0737-3039A/B, which consists of two active radio pulsars (A and B) that orbit each other with a period of 2.45 h in a mildly eccentric (e=0.088) binary system, have led to large improvements in... Read More about Strong-field gravity tests with the double pulsar.