S. Chanlaridis
A5061685688- Pulsars and Gravitational Waves Research
- Radio Astronomy Observations and Technology
- Geophysics and Gravity Measurements
- Gamma-ray bursts and supernovae
- Cosmology and Gravitation Theories
- Superconducting Materials and Applications
- Stellar, planetary, and galactic studies
- Dark Matter and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- High-pressure geophysics and materials
- Scientific Research and Discoveries
- Radiology practices and education
- Advanced X-ray and CT Imaging
- Seismic Waves and Analysis
- Radiation Dose and Imaging
- Black Holes and Theoretical Physics
- Astro and Planetary Science
Institute of Astrophysics and Space Sciences
2025
Foundation for Research and Technology Hellas
2022-2024
University of Crete
2022
Aristotle University of Thessaloniki
2014-2022
We present the results of search for an isotropic stochastic gravitational wave background (GWB) at nanohertz frequencies using second data release European Pulsar Timing Array (EPTA) 25 millisecond pulsars and a combination with first Indian (InPTA). analysed (i) full 24.7-year EPTA set, (ii) its 10.3-year subset based on modern observing systems, (iii) set InPTA ten commonly timed pulsars, (iv) data. These combinations allowed us to probe contributions instrumental noise interstellar...
The European Pulsar Timing Array (EPTA) and Indian (InPTA) collaborations have measured a low-frequency common signal in the combination of their second first data releases, respectively, with correlation properties gravitational wave background (GWB). Such may its origin number physical processes including cosmic population inspiralling supermassive black hole binaries (SMBHBs); inflation, phase transitions, strings, tensor mode generation by non-linear evolution scalar perturbations early...
The European Pulsar Timing Array (EPTA) and Indian (InPTA) collaborations have measured a low-frequency common signal in the combination of their second first data releases respectively, with correlation properties gravitational wave background (GWB). Such may its origin number physical processes including cosmic population inspiralling supermassive black hole binaries (SMBHBs); inflation, phase transitions, strings tensor mode generation by non-linear evolution scalar perturbations early...
Aims. The nanohertz gravitational wave background (GWB) is expected to be an aggregate signal of ensemble waves emitted predominantly by a large population coalescing supermassive black hole binaries in the centres merging galaxies. Pulsar timing arrays (PTAs), which are ensembles extremely stable pulsars at approximately kiloparsec distances precisely monitored for decades, most precise experiments capable detecting this background. However, subtle imprints that GWB induces on pulsar data...
Abstract 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 different choices in modeling their data, we perform comparison GWB individual noise parameters across results reported from PTAs constitute International Pulsar Timing Array (IPTA). We show despite making choices, there is no significant...
Pulsar Timing Array experiments probe the presence of possible scalar or pseudoscalar ultralight dark matter particles through decade-long timing an ensemble galactic millisecond radio pulsars. With second data release European Array, we focus on most robust scenario, in which interacts only gravitationally with ordinary baryonic matter. Our results show that masses 10^{-24.0} eV≲m≲10^{-23.3} eV cannot constitute 100% measured local density, but can have at density ρ≲0.3 GeV/cm^{3}.
We present the results of a search for continuous gravitational wave signals (CGWs) in second data release (DR2) European Pulsar Timing Array (EPTA) Collaboration. The most significant candidate event from this has frequency 4–5 nHz. Such signal could be generated by supermassive black hole binary (SMBHB) local Universe. follow-up analysis using both Bayesian and frequentist methods. gives Bayes factor 4 favour presence CGW over common uncorrelated noise process. In contrast, estimates...
We present the results of search for an isotropic stochastic gravitational wave background (GWB) at nanohertz frequencies using second data release European Pulsar Timing Array (EPTA) 25 millisecond pulsars and a combination with first Indian (InPTA). analysed (i) full 24.7-year EPTA set, (ii) its 10.3-year subset based on modern observing systems, (iii) set InPTA ten commonly timed pulsars, (iv) data. These combinations allowed us to probe contributions instrumental noise interstellar...
We present the results of a search for continuous gravitational wave signals (CGWs) in second data release (DR2) European Pulsar Timing Array (EPTA) collaboration. The most significant candidate event from this has frequency 4-5 nHz. Such signal could be generated by supermassive black hole binary (SMBHB) local Universe. follow-up analysis using both Bayesian and frequentist methods. gives Bayes factor 4 favor presence CGW over common uncorrelated noise process, while estimates p-value to...
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 different choices in modeling their data, we perform comparison GWB individual noise parameters across results reported from PTAs constitute International Pulsar Timing Array (IPTA). We show despite making choices, there is no significant difference...
We search for a stochastic gravitational wave background (SGWB) generated by network of cosmic strings using six millisecond pulsars from Data Release 2 (DR2) the European Pulsar Timing Array (EPTA). perform Bayesian analysis considering two models string loops, and compare it to simple power-law model which is expected population supermassive black hole binaries. Our main strong assumption that previously reported common red noise process SGWB. find one-parameter slightly favored over...
Ultralight axionlike particles (ALPs) can be a viable solution to the dark matter problem. The scalar field associated with ALPs, coupled electromagnetic acts as an active birefringent medium, altering polarization properties of light through which it propagates. In particular, oscillations axionic induce monochromatic variations plane linearly polarized radiation astrophysical signals. radio emission millisecond pulsars provides excellent tool search for such manifestations, given their...
Millisecond pulsars (MSPs) are laboratories for stellar evolution, strong gravity, and ultra-dense matter. Although MSPs thought to originate in low-mass X-ray binaries (LMXBs), approximately 27% do not have a binary companion, others found systems with large orbital eccentricities. Understanding how these form may provide insight into the internal properties of neutron stars (NSs). We studied formation twin compact star through rapid first-order phase transitions NS cores due mass accretion...
The nanohertz gravitational wave background (GWB) is expected to be an aggregate signal of ensemble waves emitted predominantly by a large population coalescing supermassive black hole binaries in the centres merging galaxies. Pulsar timing arrays, ensembles extremely stable pulsars, are most precise experiments capable detecting this background. However, subtle imprints that GWB induces on pulsar data obscured many sources noise. These must carefully characterized increase sensitivity GWB....
Type Ia supernovae (SNe Ia) are manifestations of stars deficient hydrogen and helium disrupting in a thermonuclear runaway. While explosions carbon-oxygen white dwarfs thought to account for the majority events, part observed diversity may be due varied progenitor channels. We demonstrate that with masses between $\sim$1.8 2.5 M$_{\odot}$ evolve into highly degenerate, near-Chandrasekhar mass cores helium-free envelopes subsequently ignite carbon oxygen explosively at densities...
(abridged) When stripped from their hydrogen-rich envelopes, stars with initial masses between $\sim$7 and 11 M$_\odot$ develop massive degenerate cores collapse. Depending on the final structure composition, outcome can range a thermonuclear explosion, to formation of neutron star in an electron-capture supernova (ECSN). It has been recently demonstrated that this mass may initiate explosive oxygen burning when central densities are still below $\rho_{\rm c} \lesssim 10^{9.6}$ g cm$^{-3}$....
Millisecond pulsars (MSPs) are laboratories for stellar evolution, strong gravity, and ultra-dense matter. Although MSPs thought to originate in low-mass X-ray binaries (LMXBs), approximately 27% lack a binary companion, while others found systems with large orbital eccentricities. Understanding how these form may provide insight into the internal properties of neutron stars (NSs). We study formation twin compact star through rapid first-order phase transitions NS cores due mass accretion...
(abridged) When stripped from their hydrogen-rich envelopes, stars with initial masses between $\sim$7 and 11 M$_\odot$ develop massive degenerate cores collapse. Depending on the final structure composition, outcome can range a thermonuclear explosion, to formation of neutron star in an electron-capture supernova (ECSN). It has been recently demonstrated that this mass may initiate explosive oxygen burning when central densities are still below $ρ_{\rm c} \lesssim 10^{9.6}$ g cm$^{-3}$....