Negative / Null Result ReportOpen accessAstrophysics
John T. Whelan, Rodrigo Tenorio, Jared K. Wofford et al. · 2023 · The Astrophysical Journal
Improved observational constraints on the orbital parameters of the low-mass X-ray binary Scorpius X-1 were recently published in Killestein et al. In the process, errors were corrected in previous orbital ephemerides, which have been used in searches for continuous gravitational waves from Sco X-1 using data from the Advanced LIGO detectors. We present the results of a reanalysis of LIGO detector data from the third observing run of Advanced LIGO and Advanced Virgo using a model-based cross-correlation search. The corrected region of parameter space, which was not covered by previous searches
View details →Negative / Null Result ReportOpen accessAstrophysics
Nima Chartab, Andrew B. Newman, Gwen C. Rudie et al. · 2025 · The Astrophysical Journal
We investigate the environmental dependence of galaxy properties at z ∼ 2.5 using the Ly α Tomography IMACS Survey (LATIS), which provides high-resolution three-dimensional maps of intergalactic medium (IGM) overdensity via Ly α forest tomography. Our analysis focuses on a UV-selected spectroscopic sample of 2185 galaxies from LATIS and a complementary set of 1157 galaxies from heterogeneous spectroscopic surveys in the COSMOS field. We compare these data sets to forward-modeled mock catalogs constructed from the IllustrisTNG300-1 simulation, incorporating realistic selection functions to matc
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Huanbin Chi, Zhi Li, Feng Wang et al. · 2026 · The Astrophysical Journal
We present a deep photometric analysis of the main-sequence (MS) population in the old, metal-rich open cluster (OC) NGC 6791 using Gaia Data Release 3 data. After correcting for differential reddening, we use the Bayesian model comparison to test whether stellar rotation can account for the observed MS broadening and find that a rotation-dominated interpretation is strongly disfavored. We therefore infer that unresolved multiplicity is the primary contributor to the photometric offsets. We derive a high- q companion fraction of 54.3% ± 2.8% for systems with q ≳ 0.5, significantly higher than
View details →Negative / Null Result ReportOpen accessAstrophysics
Barry F. Madore, Wendy L. Freedman · 2024 · The Astrophysical Journal
Using an updated and significantly augmented sample of Cepheid and tip of the red giant branch (TRGB) distances to 28 nearby spiral and irregular galaxies, covering a wide range of metallicities, we have searched for evidence of a correlation of the zero-point of the Cepheid period–luminosity relation with H ii region (gas-phase) metallicities. Our analysis, for the 21 galaxies closer than 12.5 Mpc, results in the following conclusions: (1) The zero-points of the Cepheid and TRGB distance scales are in remarkably good agreement, with the mean offset in the zero-points of the most nearby distan
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Mohit Bhardwaj, Victoria M. Kaspi, K. W. Masui et al. · 2025 · The Astrophysical Journal
Despite hundreds of detected fast radio bursts (FRBs), the faint-end slope ( γ ) of their energy distribution remains poorly constrained, hindering understanding of whether bright, cosmological FRBs and faint, Galactic magnetar SGR 1935+2154-like bursts share a common origin. In this study, we constrain this faint-end slope, modeled with a Schechter-like distribution, by searching for potential associations between bursts from the CHIME/FRB Catalog-1 and galaxies in the Local Volume. We crossmatched CHIME/FRB Catalog-1 FRBs with 495 Local Volume galaxies within 21 Mpc, identified from the HECA
View details →Replication FailureOpen accessAstrophysics
J. Ming, M. A. Papa, H.-B. Eggenstein et al. · 2024 · The Astrophysical Journal
We perform a search for continuous nearly monochromatic gravitational waves from the central compact objects associated with the supernova remnants Vela Jr. and G347.3. Over 10 ^18 different waveforms are considered, covering signal frequencies between 20 and 1300 Hz (20 and 400 Hz) for G347.3-0.5 (Vela Jr.) and a very broad range of frequency derivatives. The data set used for this first search is from the second observing run of LIGO (O2). Thousands of volunteers donating compute cycles through the computing project Einstein@Home have made this endeavor possible. Following the Einstein@Home
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B. King, T. Heinzl, T. G. Blackburn · 2023 · European Physical Journal C: Particles and Fields
Abstract By combining an adiabatic approach based on a ‘locally monochromatic’ approximation with a local Hilbert transform, it is demonstrated how vacuum birefringence in the strong field regime can be calculated using a rate approach suitable for Monte Carlo simulation codes. Results for the flipping of the photon’s polarisation (helicity) are benchmarked with evaluation of exact expressions in a circularly (linearly) polarised plane wave of finite extent. For the circularly polarised case, the Heisenberg–Euler approach predicts a null result; an approximation similar to the ‘locally constan
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Chen Du, Yong-Feng Huang, Zhi-Bin Zhang et al. · 2024 · The Astrophysical Journal
Fast radio bursts (FRBs) are bright radio transients with millisecond durations, which typically occur at extragalactic distances. The association of FRB 20200428 with the Galactic magnetar SGR J1935+2154 strongly indicates that they could originate from neutron stars, which naturally leads to the expectation that periodicity connected with the spinning of magnetars should exist in the activities of repeating FRBs. However, previous studies have failed to find any signatures supporting such a conjecture. Here we perform a thorough search for short-timescale periodicity in the four most active
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Yuta Hamada, Masatoshi Yamada · 2017 · European Physical Journal C: Particles and Fields
Abstract The null result in the LHC may indicate that the standard model is not drastically modified up to very high scales, such as the GUT/string scale. Having this in the mind, we suggest a novel leptogenesis scenario realized in the false vacuum of the Higgs field. If the Higgs field develops a large vacuum expectation value in the early universe, a lepton number violating process is enhanced, which we use for baryogenesis. To demonstrate the scenario, several models are discussed. For example, we show that the observed baryon asymmetry is successfully generated in the standard model with
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