Archive for blazars

Weekly Update from the Open Journal of Astrophysics 15/08/2026

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , on August 15, 2026 by telescoper

Although it’s still holiday season for some, it’s time once more for another Saturday update of activity at the Open Journal of Astrophysics. Since the last update we have published a further four papers, bringing the number in Volume 9 (2026) to 171 and the total so far published by OJAp up to 619.

I continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week was published on Monday 10th August in the folder High-Energy Astrophysical Phenomena. “Search for neutrino emission from blazar γ-ray flares accounting for possible neutrino time delays” by Egor Podlesny & Foteini Oikonomou (Norwegian University of Science & Technology, Trondheim, Norway) investigates high-energy neutrino emissions associated with blazar flares, using data from IceCat-1, MOJAVE, CGRaBS, and Fermi-LAT. A slight correlation was found, consistent with the null hypothesis.

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Search for neutrino emission from blazar γ-ray flares accounting for possible neutrino time delays" by Egor Podlesny & Foteini Oikonomou (Norwegian University of Science & Technology, Trondheim, Norway)

doi.org/10.33232/001c.166774

August 10, 2026, 7:15 am 1 boosts 1 favorites

The second paper for this week, published on Tuesday 11th August in the folder Cosmology and Nongalactic Astrophysics is “The velocity coherence scale: a novel probe of cosmic homogeneity and a potential standard ruler” by Leonardo Giani (Swinburne University of Technology), Cullan Howlet (U. Queensland), Chris Blake (Swinburne), Ryan J. Turner (Australia National University) and Tamara M. Davis (U. Queensland) – all in Australia. This paper argues that velocity coherence scale, a measure that identifies the transition point of galaxy motion from correlated to anti-correlated, could potentially characterize the onset of cosmic homogeneity.

The overlay looks like this:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "The velocity coherence scale: a novel probe of cosmic homogeneity and a potential standard ruler" by Leonardo Giani (Swinburne U. Tech.), Cullan Howlet (U. Queensland), Chris Blake (Swinburne), Ryan J. Turner (ANU) and Tamara M. Davis (U. Queensland) – all in Australia.

doi.org/10.33232/001c.166880

August 11, 2026, 7:01 am 0 boosts 1 favorites

The third paper of the week, also published on Tuesday 11th Augus, but in the folder Astrophysics of Galaxies, is “A GLIMPSE of the 99%: a census of the faintest galaxies during the epoch of reionization and its implications for galaxy formation models” by Hakim Atek (Sorbonne Université, Paris, France) and 21 others based around the world.

The overlay is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "A GLIMPSE of the 99%: a census of the faintest galaxies during the epoch of reionization and its implications for galaxy formation models" by Hakim Atek (Sorbonne Université, Paris, France) and 21 others based around the world.

doi.org/10.33232/001c.166816

August 11, 2026, 7:39 am 0 boosts 1 favorites

The fourth and final paper of the week was published on Wednesday 12th August in the folder Astrophysics of Galaxies: “Dust and Grain Size Evolution in Galaxy Simulations: What Matters and What Does Not” by Massimiliano Parente & Desika Narayanan (U. Florida, USA) and Paul Torrey (U. Virginia, USA) presents the first implementation of an evolving dust grain size distribution within a model of galaxy evolution, successfully reproducing key observational constraints and exploring the mechanisms shaping galaxies.

The overlay is here:

The officially-accepted version of the paper can be found on arXiv here and the Fediverse announcement here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Dust and Grain Size Evolution in Galaxy Simulations: What Matters and What Does Not" by Massimiliano Parente & Desika Narayanan (U. Florida, USA) and Paul Torrey (U. Virginia, USA)

doi.org/10.33232/001c.166984

August 12, 2026, 6:07 am 0 boosts 1 favorites

That’s all for this week. We’re just ticking over at the moment, and steadily building up a backlog of papers to publish while we wait for authors to put their final versions on arXiv. I have a feeling there’s going to be a big splurge sometime. Will it be next week? We’ll find out next Saturday!

Weekly Update from the Open Journal of Astrophysics – 23/05/2026

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , on May 23, 2026 by telescoper

It’s Saturday once again, so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further six papers, bringing the number in Volume 9 (2026) to 110 and the total so far published by OJAp up to 558.

I will continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week, published on Monday 18th May in the folder Instrumentation and Methods for Astrophysics is “Edges In Coadded Images” by Erin Sheldon (Brookhaven National Laboratory, USA). This paper describes a study exploring how image discontinuities and noise impact weak gravitational lensing measurements, finding no significant biases under typical conditions. Biases occur only in extreme cases, but can be mitigated.

The overlay for this paper is here

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Edges In Coadded Images" by Erin Sheldon (Brookhaven National Laboratory, USA)

doi.org/10.33232/001c.162176

May 18, 2026, 6:43 am 1 boosts 0 favorites

The second paper for this week, also published on Monday 18th May but in the folder Cosmology and Nongalactic Astrophysics, is “Joint cosmological fits to DESI-DR1 full-shape clustering and weak gravitational lensing in configuration space” by A. Semenaite (Swinburne Institute of Technology, Australia) and 72 other authors from all round the world. This paper presents a cosmological analysis of correlations between the DESI-DR1 Bright Galaxy Survey and Luminous Red Galaxy samples and overlapping shear measurements from various weak lensing surveys.

The overlay for this one is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Joint cosmological fits to DESI-DR1 full-shape clustering and weak gravitational lensing in configuration space " by A. Semenaite (Swinburne Institute of Technology, Australia) and 72 others from all round the world.

doi.org/10.33232/001c.162334

May 18, 2026, 6:52 am 1 boosts 1 favorites

Next one up, the third paper of the week, and the third published on Monday 18th May, and in the folder Cosmology and Nongalactic Astrophysics is “Probing Dark Energy Microphysics with kSZ Tomography” by Julius Adolff, Selim Hotinli and Neal Dalal (all of the Perimeter Institute, Canada). This paper explores how kinetic Sunyaev-Zel’dovich tomography and galaxy clustering can enhance our understanding of dark energy and its effects, potentially revealing its microphysical properties in future surveys.

The overlay for this one is here:

The final, accepted version can be found on arXiv here and the Mastodon announcement is here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Probing Dark Energy Microphysics with kSZ Tomography" by Julius Adolff, Selim Hotinli and Neal Dalal (Perimeter Institute, Canada)

doi.org/10.33232/001c.162336

May 18, 2026, 7:04 am 1 boosts 0 favorites

The fourth paper this week, published on Wednesday May 20th is “A Census of Variable Radio Sources at 3 GHz” by Yjan A. Gordon, Peter S. Ferguson, Michael N. Martinez and Eric J. Hooper (all of the University of Wisconsin, USA). This article, published in the folder Astrophysics of Galaxies, uses data from the Very Large Array Sky Survey to analyze variability in the radio sky, finding most changes consistent with blazars and quasars.

The overlay is here:

The officially accepted version can be found on arXiv here and here is the Mastodon announcement:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "A Census of Variable Radio Sources at 3 GHz" by Yjan A. Gordon, Peter S. Ferguson, Michael N. Martinez & Eric J. Hooper (U. Wisconsin, USA)

doi.org/10.33232/001c.162407

May 20, 2026, 2:52 pm 0 boosts 2 favorites

The fifth article of this week was published on Friday 22nd May in the folder Instrumentation and Methods for Astrophysics. The title is “Uncovering the Next Galactic Supernova with the Vera C. Rubin Observatory” by John Banovetz (Lawrence Berkeley Lab., USA), Claire-Alice Hebert & Peter B. Denton (Brookhaven National Lab., USA), Dan Scolnic (Duke University, USA), Anze Slosar (Brookhaven) and Chris Walter (Duke). The paper presents a study simulating how effectively the Vera C. Rubin Observatory can localize supernovae using neutrino triggers, finding a 57-97% success rate based on stellar mass density predictions.

The overlay is here:

You can find the authorized version of this paper on arXiv here and the Fediverse announcement is here:

Open Journal of Astrophysics

New Publlication at the Open Journal of Astrophysics: "Uncovering the Next Galactic Supernova with the Vera C. Rubin Observatory" by John Banovetz (Lawrence Berkeley Lab., USA), Claire-Alice Hebert & Peter B. Denton (Brookhaven National Lab., USA) , Dan Scolnic (Duke U., USA) , Anze Slosar (Brookhaven), and Chris Walter (Duke)

doi.org/10.33232/001c.162454

May 22, 2026, 8:31 am 0 boosts 1 favorites

Last, but by no means least, this week we have “Pulsar timing solutions for 17 pulsars at 150 MHz from the Irish LOFAR station” by David J. McKenna (ASTRON, The Netherlands), Evan F. Keane (Trinity College Dublin, Ireland), Peter T. Gallagher (DIAS, Ireland) and Joe McCauley (Trinity). This was published on Friday 22nd May in the folder High-Energy Astrophysical Phenomena. It presents a demonstration of the use of international Low Frequency Array (LOFAR) stations in tracking and characterizing pulsars, providing new insights into these neutron stars’ emission properties.

The overlay for this one is here:

You can find the authorized version of this paper on arXiv here and the Fediverse announcement is here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Pulsar timing solutions for 17 pulsars at 150 MHz from the Irish LOFAR station" by David J. McKenna (ASTRON, The Netherlands), Evan F. Keane (Trinity College Dublin, Ireland), Peter T. Gallagher (DIAS, Ireland) and Joe McCauley (Trinity)

doi.org/10.33232/001c.162455

May 22, 2026, 8:59 am 0 boosts 0 favorites

And that concludes this week’s update. I’ll do another one next Saturday.

Weekly Update from the Open Journal of Astrophysics – 13/12/2025

Posted in OJAp Papers, Open Access, The Universe and Stuff with tags , , , , , , , , , , , , , , , , , , , , , , , , , , on December 13, 2025 by telescoper

It’s time once again for the usual Saturday morning update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published a further five papers, which brings the number in Volume 8 (2025) up to 195, and the total so far published by OJAp up to 430.

The first paper this week is “Cosmic Rays Masquerading as Cool Cores: An Inverse-Compton Origin for Cool Core Cluster Emission” by Philip F. Hopkins (Caltech), Eliot Quataert (Princeton), Emily M. Silich, Jack Sayers, Sam B. Ponnada and Isabel S. Sands (Caltech).  This was published on Tuesday 9th December 2025 in the folder marked High-Energy Astrophysical Phenomena. It presents an argument  that cosmic-ray inverse-compton emission could contribute significantly to the X-ray surface brightness (SB) in cool-corre clusters, implying that gas densities may have been overestimated therein.

The overlay is here:

You can find the officially accepted version on arXiv here and the Fediverse announcement is here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Cosmic Rays Masquerading as Cool Cores: An Inverse-Compton Origin for Cool Core Cluster Emission" by

Philip F. Hopkins (Caltech), Eliot Quataert (Princeton), Emily M. Silich, Jack Sayers, Sam B. Ponnada and Isabel S. Sands (Caltech)

doi.org/10.33232/001c.154053

December 9, 2025, 7:22 am 1 boosts 0 favorites

The second paper of the week is “Detecting False Positives With Derived Planetary Parameters: Experimenting with the KEPLER Dataset” by Ayan Bin Rafaih (Aitchison College, Lahore, Pakistan) and Zachary Murray (Université Côte d’Azur, France). This one was published on 9th December 2025 in the folder Earth and Planetary Astrophysics. It is an investigation into the performance of a range of machine-learning algorithms on the KEPLER dataset, using precision-recall trade-off and accuracy metrics.

The overlay is here:

You can find the official version of this one on arXiv here. The federated announcement on Mastodon is here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Detecting False Positives With Derived Planetary Parameters: Experimenting with the KEPLER Dataset" by Ayan Bin Rafaih (Aitchison College, Lahore, Pakistan) and Zachary Murray (Université Côte d’Azur, France)

doi.org/10.33232/001c.154054

December 9, 2025, 7:34 am 1 boosts 0 favorites

Next one up is “The role of peculiar velocity uncertainties in standard siren cosmology” by Chris Blake and Ryan J. Turner (Swinburne, Australia). This paper discusses the impact of peculiar velocities on the error in H0 determinations from local distance indicators with observed redshifts, incorporating the effect of bulk flows. It was published on Tuesday 9th December in the folder Cosmology and Nongalactic Astrophysics.

The overlay is here:

You can find the official accepted version on arXiv here. The fediverse announcement is here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "The role of peculiar velocity uncertainties in standard siren cosmology" by Chris Blake and Ryan J. Turner (Swinburne, Australia)

doi.org/10.33232/001c.154055

December 9, 2025, 7:47 am 1 boosts 0 favorites

The fourth article of the week is “Transient QPOs of Fermi-LAT blazars with Linearly Multiplicative Oscillations” by P. Penil (Clemson University, USA) and 7 others based in the USA, Italy and Germany. This was published on Thursday 10th December in the folder High-Energy Astrophysical Phenomena. This paper presents an investigation of patterns of quasi-periodic oscillations in observed blazar systems characterized by periodic multiplicative amplitudes including both the periodicities and long-term variations.  The overlay is here:

You can find the official published version on arXiv here. The Fediverse announcement follows:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Transient QPOs of Fermi-LAT blazars with Linearly Multiplicative Oscillations" by P. Penil (Clemson University, USA) and 7 others based in the USA, Italy and Germany

doi.org/10.33232/001c.154123

December 10, 2025, 12:22 pm 0 boosts 1 favorites

The last paper for this week is “Tidally Delayed Spin-Down of Very Low Mass Stars” by Ketevan Kotorashvili and Eric G. Blackman (U. Rochester, USA). This was published on Friday 12th December (yesterday) in the folder Solar and Stellar Astrophysics. It discusses the effect of tides from sub-stellar companions on rotational evolution of very low-mass stars, suggesting that these may explain the dearth of field, late-type M dwarfs with intermediate rotation periods.

The overlay is here:

 

You can find the officially-accepted version on arXiv here, and the Mastodon announcement is here:

Open Journal of Astrophysics

New Publication at the Open Journal of Astrophysics: "Tidally Delayed Spin-Down of Very Low Mass Stars" by Ketevan Kotorashvili and Eric G. Blackman (U. Rochester, USA)

doi.org/10.33232/001c.154268

December 12, 2025, 10:31 am 1 boosts 0 favorites

 

And that concludes the update for this week. I will do another of these regular announcements next Saturday, which will be the last such update for 2025. Will we make it past 200 for the year? Tune in next week to find out!