Article
Astronomy & Astrophysics
Andres Banares-Hernandez, Andres Castillo, Jorge Martin Camalich, Giuliano Iorio
Summary: In this paper, we investigate the viability of fuzzy dark matter by analyzing rotation curves from the LITTLE THINGS in 3D catalog. While fuzzy dark matter provides a good fit to the data, there are some inconsistencies with the predictions of the model.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Moritz S. Fischer, Marcus Brueggen, Kai Schmidt-Hoberg, Klaus Dolag, Felix Kahlhoefer, Antonio Ragagnin, Andrew Robertson
Summary: Studies have shown that the implementation of SIDM models based on frequent scattering can accurately simulate small-scale dark matter issues and have significant implications for predicting differences between SIDM models that predict rare and frequent scattering.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Moritz S. Fischer, Marcus Brueggen, Kai Schmidt-Hoberg, Klaus Dolag, Felix Kahlhoefer, Antonio Ragagnin, Andrew Robertson
Summary: In this study, the first cosmological simulation of frequent dark matter self-interactions, corresponding to small-angle scatterings, is performed. The results show that overall, large-angle and small-angle scatterings behave similarly with a few exceptions. The number of satellites is considerably suppressed for frequent self-interactions compared to rare self-interactions with the same cross-section. The degeneracy between the two cases may be broken through a combination of multiple measures.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Moritz S. Fischer, Marcus Brueggen, Kai Schmidt-Hoberg, Klaus Dolag, Antonio Ragagnin, Andrew Robertson
Summary: This study investigates the effects of dark matter self-interactions in merging systems of galaxies and galaxy clusters. The research focuses on the impact of small-angle scatterings on astrophysical observables and related quantities. The results highlight the sensitivity of the peak finding method and the potential for large dark matter-galaxy offsets in minor mergers with frequent self-interactions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Moritz S. Fischer, Nils-Henrik Durke, Katharina Hollingshausen, Claudius Hammer, Marcus Brueggen, Klaus Dolag
Summary: Mergers of galaxy clusters are useful for studying dark matter physics, and we investigated the influence of the intracluster medium (ICM) on dark matter-galaxy offsets in self-interacting dark matter models. Our simulations showed that the ICM has little effect on initial offsets, but can amplify them at later stages. We also found that different dark matter models affect the distribution of dark matter, as well as galaxies and the ICM.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Taha Dawoodbhoy, Paul R. Shapiro, Tanja Rindler-Daller
Summary: Scalar field dark matter (SFDM) composed of ultralight bosons is of interest as an alternative to standard cold dark matter, with novel structure-formation dynamics described by the coupled Schrodinger-Poisson equations. SFDM can inhibit structure below the de Broglie wavelength and in the Thomas-Fermi regime with an added repulsive self-interaction. Simulation results demonstrate SFDM-TF haloes form with cores of a certain size and pass tests based on rotation curves of dwarf galaxies in the local Universe.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
R. A. Jackson, S. Kaviraj, G. Martin, J. E. G. Devriendt, A. Slyz, J. Silk, Y. Dubois, S. K. Yi, C. Pichon, M. Volonteri, H. Choi, T. Kimm, K. Kraljic, S. Peirani
Summary: In the standard ΛCDM paradigm, dwarf galaxies are expected to be dark matter-rich, but recent observations have shown dwarf galaxies with extremely low dark matter content, potentially questioning the validity of the standard model. Research demonstrates that the sustained stripping of dark matter in tidal interactions between massive galaxies and dwarf satellites naturally produces dark matter-deficient dwarfs, leading to a large scatter in the halo-to-stellar mass relation in the dwarf regime.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Lauren H. Cooke, Rebecca C. Levy, Alberto D. Bolatto, Joshua D. Simon, Andrew B. Newman, Peter Teuben, Brandon D. Davey, Melvyn Wright, Elizabeth Tarantino, Laura Lenkic, Vicente Villanueva
Summary: Rotation curves of spiral dwarf galaxies were examined using ALMA, and it was found that these relatively massive dwarfs have steeper dark matter density profiles than predicted by simulations. This suggests the possibility of stronger gas inflows, overestimate of accretion or feedback events in the simulations, or a combination of these effects.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Paul R. Shapiro, Taha Dawoodbhoy, Tanja Rindler-Daller
Summary: Scalar field dark matter (SFDM) comprised of ultralight bosons can inhibit small-scale structure formation while behaving like standard cold dark matter (CDM) on large scales. By simulating halo formation and deriving transfer functions, researchers can study SFDM dynamics in cosmological contexts.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Grace E. Lawrence, Alan R. Duffy, Chris A. Blake, Philip F. Hopkins
Summary: High-resolution simulations show that the variability of dark matter around the Solar Circle of a Milky Way-type analogue galaxy can complicate interpretations of direct dark matter detection experiments. The presence of high-velocity substructures in the velocity distribution function indicates deviations from the commonly assumed Maxwell Boltzmann form. The impact of these velocity substructures on summary statistics is generally low.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Jan Novotny, Zdenek Stuchlik, Jan Hladik
Summary: Our study aims to gain insight into the physical conditions of DM haloes in dwarf galaxies by using a physically based model, revealing three classes of dwarf galaxies based on their velocity profiles. The results suggest the possibility of different types of DM composing the haloes, with matches similar in quality to previous models.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
L. Gajovic, F. Welzmueller, V. Heesen, F. de Gasperin, M. Vollmann, M. Brueggen, A. Basu, R. Beck, D. J. Schwarz, D. J. Bomans, A. Drabent
Summary: By using the non-detection of 150 MHz radio continuum emission from dwarf spheroidal (dSph) galaxies with the LOw Frequency ARray (LOFAR), we derived constraints on the annihilation cross section of weakly interacting massive particles (WIMPs) in electron-positron pairs. Our results provide upper limits on the WIMP cross section, assuming diffusion approximation and the existence of magnetic fields in cosmic ray transport.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Emily J. E. Charles, Michelle L. M. Collins, R. Michael Rich, Justin Read, Stacy Y. Kim, Rodrigo A. Ibata, Nicolas F. Martin, Scott C. Chapman, Eduardo Balbinot, Daniel R. Weisz
Summary: In this study, we find that And XXV is a dwarf spheroidal galaxy dominated by dark matter, with a relatively high mass and significant differences compared to other galaxies of similar mass.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Ali Rida Khalifeh, Raul Jimenez
Summary: The discovery of 19 dwarf galaxies without dark matter supports the ΛCDM cosmological model and prompts exploration of modifications to gravity models to accommodate their existence. The findings suggest the need for additional contributions to the Virial theorem from modifications of gravity in the presence of galaxies devoid of dark matter.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Michelle L. M. Collins, Justin Read, Rodrigo A. Ibata, R. Michael Rich, Nicolas F. Martin, Jorge Penarrubia, Scott C. Chapman, Erik J. Tollerud, Daniel R. Weisz
Summary: In this study, dynamical observations were conducted on the And XXI galaxy, revealing a lower dark matter density than expected. Analysis of member stars' metallicity suggested possible explanations for And XXI's low density to be extreme tidal stripping or inhabiting a low-concentration halo.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
T. W. Shimwell, M. J. Hardcastle, C. Tasse, P. N. Best, H. J. A. Rottgering, W. L. Williams, A. Botteon, A. Drabent, A. Mechev, A. Shulevski, R. J. van Weeren, L. Bester, M. Bruggen, G. Brunetti, J. R. Callingham, J. E. Conway, T. J. Dijkema, K. Duncan, F. de Gasperin, C. L. Hale, M. Haverkorn, B. Hugo, N. Jackson, M. Mevius, G. K. Miley, L. K. Morabito, R. Morganti, A. Offringa, J. B. R. Oonk, D. Rafferty, J. Sabater, D. J. B. Smith, D. J. Schwarz, O. Smirnov, S. P. O'Sullivan, H. Vedantham, G. J. White, J. G. Albert, L. Alegre, B. Asabere, D. J. Bacon, A. Bonafede, E. Bonnassieux, M. Brienza, M. Bilicki, M. Bonato, G. Calistro Rivera, R. Cassano, R. Cochrane, J. H. Croston, V Cuciti, D. Dallacasa, A. Danezi, R. J. Dettmar, G. Di Gennaro, H. W. Edler, T. A. Ensslin, K. L. Emig, T. M. O. Franzen, C. Garcia-Vergara, Y. G. Grange, G. Gurkan, M. Hajduk, G. Heald, V Heesen, D. N. Hoang, M. Hoeft, C. Horellou, M. Iacobelli, M. Jamrozy, V Jelic, R. Kondapally, P. Kukreti, M. Kunert-Bajraszewska, M. Magliocchetti, V Mahatma, K. Malek, S. Mandal, F. Massaro, Z. Meyer-Zhao, B. Mingo, R. I. J. Mostert, D. G. Nair, S. J. Nakoneczny, E. Orru, T. Pasini, I Prandoni, H. E. van Piggelen, K. Rajpurohit, E. Retana-Montenegro, C. J. Riseley, A. Rowlinson, A. Saxena, C. Schrijvers, F. Sweijen, T. M. Siewert, R. Timmerman, M. Vaccari, J. Vink, J. L. West, X. Zhang, J. Zheng
Summary: This article presents the data release of LOFAR Two-metre Sky Survey, which covers 27% of the northern sky with 120-168 MHz images. The catalogue includes 4,396,228 radio sources, most of which have never been detected at radio wavelengths before. The images were derived from extensive and automated data processing, including correction for instrumental properties and ionospheric distortions. The release of Stokes I, Q, U, and V images, as well as calibrated uv-data, enables the thorough scientific exploitation of this unique dataset.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Martijn S. S. L. Oei, Reinout J. van Weeren, Martin J. Hardcastle, Andrea Botteon, Tim W. Shimwell, Pratik Dabhade, Aivin R. D. J. G. I. B. Gast, Huub J. A. Roettgering, Marcus Brueggen, Cyril Tasse, Wendy L. Williams, Aleksandar Shulevski
Summary: This paper introduces a newly discovered giant radio galaxy Alcyoneus, which is one of the largest structures in the universe. Through observation and analysis, researchers found that some characteristics of this galaxy are lower than the average level, but similar to other giant radio galaxies. Therefore, it is concluded that the formation of giant radio galaxies does not necessarily require very massive stars or central black holes, and a low-density environment may be an explanation.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
I Heywood, M. J. Jarvis, C. L. Hale, I. H. Whittam, H. L. Bester, B. Hugo, J. S. Kenyon, M. Prescott, O. M. Smirnov, C. Tasse, J. M. Afonso, P. N. Best, J. D. Collier, R. P. Deane, B. S. Frank, M. J. Hardcastle, K. Knowles, N. Maddox, E. J. Murphy, I Prandoni, S. M. Randriamampandry, M. G. Santos, S. Sekhar, F. Tabatabaei, A. R. Taylor, K. Thorat
Summary: MIGHTEE is a galaxy evolution survey using simultaneous radio continuum, spectropolarimetry, and spectral line observations from the South African MeerKAT telescope. The data processing strategy for MIGHTEE's total intensity continuum has been described and validated, resulting in image products forming the basis of the Early Science continuum data release. The survey covers multiple extragalactic deep fields and aims to meet survey specifications with thermal noise levels below 2 Jy beam(-1).
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
B. Barkus, J. H. Croston, J. Piotrowska, B. Mingo, P. N. Best, M. J. Hardcastle, R. I. J. Mostert, H. J. A. Rottgering, J. Sabater, B. Webster, W. L. Williams
Summary: Extended radio sources play an important role in deep radio surveys, allowing for detailed exploration of the physics of active galaxies and their surroundings. Identifying the optical host galaxies for these complex and diverse extended sources is challenging. This study presents a novel method using ridgelines to automate the identification of host galaxies for extended sources. The results show that ridgelines can be versatile in providing information about spatial structure and brightness distributions, enabling both optical host identification and morphological studies in radio surveys.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
G. H. Heald, V Heesen, S. S. Sridhar, R. Beck, D. J. Bomans, M. Brueggen, K. T. Chyty, A. Damas-Segovia, R-J Dettmar, J. English, R. Henriksen, S. Ideguchi, J. Irwin, M. Krause, J-T Li, E. J. Murphy, B. Nikiel-Wroczynski, J. Piotrowska, R. J. Rand, T. Shimwell, Y. Stein, C. J. Vargas, Q. D. Wang, R. J. van Weeren, T. Wiegert
Summary: New radio continuum images of the edge-on starburst galaxy NGC 5775 were presented, revealing the extent of the non-thermal radio halo and estimating the magnetic field strength. An updated model incorporating an iso-thermal wind with a 'flux tube' geometry suggests that the wind influences the cosmic ray propagation and mass flow of interstellar material.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
F. Davis, S. Kaviraj, M. J. Hardcastle, G. Martin, R. A. Jackson, K. Kraljic, K. Malek, S. Peirani, D. J. B. Smith, M. Volonteri, L. Wang
Summary: In this study, optical and radio data were combined to investigate AGN in nearby dwarf galaxies. The results showed that AGN and control samples have similar environments, star formation rates, and incidence of tidal features. The properties of the AGN were explored using simulations, and it was found that AGN feedback could be plausible and important for dwarf galaxy evolution.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
B. Mingo, J. H. Croston, P. N. Best, K. J. Duncan, M. J. Hardcastle, R. Kondapally, I Prandoni, J. Sabater, T. W. Shimwell, W. L. Williams, R. D. Baldi, M. Bonato, M. Bondi, P. Dabhade, G. Gurkan, J. Ineson, M. Magliocchetti, G. Miley, J. C. S. Pierce, H. J. A. Rottgering
Summary: This study investigates the relationship between accretion mode and radio morphology for a sample of 286 well-resolved radio galaxies using the LOFAR Two-metre Sky Survey Deep Fields (LoTSS-Deep) data release. The results show that radio-loud active galaxies can have two accretion modes, radiatively inefficient (RI) and radiatively efficient (RE), and both can produce FRII structures. The study also finds a population of low-luminosity FRII galaxies, indicating that FRII radio structures can exist at all radio luminosities. Furthermore, the probability of producing FRI or FRII radio morphology is directly linked to stellar mass, while RE accretion occurs in systems with high specific star formation rate.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
V Heesen, M. Staffehl, A. Basu, R. Beck, M. Stein, F. S. Tabatabaei, M. J. Hardcastle, K. T. Chyzy, T. W. Shimwell, B. Adebahr, R. Beswick, D. J. Bomans, A. Botteon, E. Brinks, M. Brueggen, R-J Dettmar, A. Drabent, F. de Gasperin, G. Guerkan, G. H. Heald, C. Horellou, B. Nikiel-Wroczynski, R. Paladino, J. Piotrowska, H. J. A. Roettgering, D. J. B. Smith, C. Tasse
Summary: This study investigates the radio-star formation rate relationship in galaxies using low-frequency radio observations. The results show that more massive galaxies with higher star formation rates have stronger radio signals. The study also reveals variations in the radio spectral index, with steeper indices in galaxies with higher SFRs.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
M. Arias, A. Botteon, C. G. Bassa, S. van der Jagt, R. J. van Weeren, S. P. O'Sullivan, Q. Bosschaart, R. S. Dullaart, M. J. Hardcastle, J. W. T. Hessels, T. Shimwell, M. M. Slob, J. A. Sturm, C. Tasse, N. C. M. A. Theijssen, J. Vink
Summary: We report the discovery of a ring of low surface brightness radio emission around the Calvera pulsar, indicating a possible supernova remnant. The ring shows positional coincidence with the pulsar and an X-ray-emitting non-equilibrium ionization plasma, suggesting its association with the supernova remnant interpretation.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
V Heesen, T-L Klocke, M. Brueggen, F. S. Tabatabaei, A. Basu, R. Beck, A. Drabent, B. Nikiel-Wroczynski, R. Paladino, S. Schulz, M. Stein
Summary: This study investigates the origin and properties of magnetic fields in late-type galaxies. By measuring the magnetic field strengths in 39 galaxies and analyzing the relations between magnetic fields and gas density, interstellar medium density, and molecular gas density, it concludes that the magnetic field is regulated by the saturation of small-scale dynamo.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Rafael I. J. Mostert, Kenneth J. Duncan, Lara Alegre, Huub J. A. Rottgering, Wendy L. Williams, Philip N. Best, Martin J. Hardcastle, Raffaella Morganti
Summary: The study aims to automate the radio component association of large (>15 arcsec) radio components using machine learning. By turning the association problem into a classification problem, an adapted Fast region-based convolutional neural network was trained to mimic expert annotations. Through data augmentation and using predictions from an existing gradient boosting classifier, the model simplifies the component association process, providing same associations as manual efforts in 85.3% of cases.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Lara Alegre, Jose Sabater, Philip Best, Rafael I. J. Mostert, Wendy L. Williams, Gulay Gurkan, Martin J. Hardcastle, Rohit Kondapally, Tim W. Shimwell, Daniel J. B. Smith
Summary: This paper uses machine learning to classify and associate radio sources, improving model performance, and the results have important practical applications.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
L. Gajovic, F. Welzmueller, V. Heesen, F. de Gasperin, M. Vollmann, M. Brueggen, A. Basu, R. Beck, D. J. Schwarz, D. J. Bomans, A. Drabent
Summary: By using the non-detection of 150 MHz radio continuum emission from dwarf spheroidal (dSph) galaxies with the LOw Frequency ARray (LOFAR), we derived constraints on the annihilation cross section of weakly interacting massive particles (WIMPs) in electron-positron pairs. Our results provide upper limits on the WIMP cross section, assuming diffusion approximation and the existence of magnetic fields in cosmic ray transport.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Alessandro Ignesti, Marisa Brienza, Benedetta Vulcani, Bianca M. Poggianti, Antonino Marasco, Rory Smith, Martin J. Hardcastle, Andrea Botteon, Ian D. Roberts, Jacopo Fritz, Rosita Paladino, Myriam Gitti, Anna Wolter, Neven Tomicic, Sean McGee, Alessia Moretti, Marco Gullieuszik, Alexander Drabent
Summary: We report the serendipitous discovery of an unprecedented interaction between the radio lobe of a radio galaxy and a spiral galaxy. The interaction, which occurred between the central galaxy GIN 049 and the spiral galaxy JO36, resulted in a positive feedback event for JO36, leading to a significant increase in its star formation rate.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
M. Stimpson, M. J. Hardcastle, M. G. H. Krause
Summary: In this study, we present relativistic magnetohydrodynamic simulations of jets interacting with spherically symmetric cluster atmospheres. By analyzing synthetic emission maps and examining dynamic, energetic, and polarimetric data, we find that the cluster atmosphere and jet power play a crucial role in shaping the morphology and energy distribution of the jets.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)