Christopher Harvey-Hawes

Through a gravitational lens effect caused by a massive foreground cluster of galaxies (MACS J0138), multiple images of a perfectly aligned background galaxy (MRG-M0138) are created, including the supernova Encore it hosts. This image was captured by JWST in 2023.

#APOD Astronomy Picture of the Day

SN Encore: A Second Supernova Seen Several Times

Credits: NASA, ESA, CSA, STScI, J. Pierel (STScI) & A. Newman (Carnegie Inst. for Science) 🧪🔭
www.star.ucl.ac.uk/~apod/apod/a...

New Publication at the Open Journal of Astrophysics: "The matter with(in) CPL" by Leonardo Giani (U. Queensland, Australia), Rodrigo Von Marttens (Universidade Federal da Bahia, Brazil) and Oliver Fabio Piattella (Universita degli Studi dell’Insubria, Italy)

doi.org/10.33232/001...

A collage of seven by eight squares containing examples of gravitational lenses. Each example typically comprises a bright centre with smears of stars in an arc or multiple arcs around it as a result of light travelling towards Euclid from distant galaxies being bent and distorted by normal and dark matter in the foreground. In some rare cases the smearing is in a complete ring, creating a so-called Einstein Ring.

Another collage of seven by eight squares containing examples of gravitational lenses. Each example typically comprises a bright centre with smears of stars in an arc or multiple arcs around it as a result of light travelling towards Euclid from distant galaxies being bent and distorted by normal and dark matter in the foreground. In some rare cases the smearing is in a complete ring, creating a so-called Einstein Ring.

How about some lunchtime lensing? 🥪🔎

A team based at @ox.ac.uk , Portsmouth and @newcastleuni.bsky.social universities combined the power of citizen scientists and AI to sift through the more than one million galaxies seen in Euclid’s latest data, searching for strong gravitational lenses... (1/4)

Just my luck that as soon as I finish my thesis intro, then DES, DESI, Euclid + more release a seemingly endless list of papers 😅 #cosmolgy

🔊 New BAO analysis from the 3-year observations (DR2). Long story short, as follows.
1. DESI alone is consistent with LCDM. 👉 Boring
2. DESI and Planck have a 2.3 discrepancy in Ωm-H0rd plane. 👉Interesting.

A collage of fourteen by eight squares containing examples of gravitational lenses. Each example typically comprises a bright centre with smears of stars in an arc or multiple arcs around it as a result of light travelling towards Euclid from distant galaxies being bent and distorted by normal and dark matter in the foreground. In some rare cases the smearing is in a complete ring, creating a so-called Einstein Ring.

Using #AI models & #CitizenScience contributions, another first catalogue of 500 galaxy-galaxy strong lens candidates is also released today, almost all of which were previously unknown. 8/
🔭🧪 #astrosci

New Publication out in PRD! 🎉
link.aps.org/doi/10.1103/...
@apsphysics.bsky.social #blackholes

Excellent paper by Tania Barone has this lovely image by PhD student Huimin Qu arxiv.org/abs/2503.08041

QZO: A Catalog of 5 Million Quasars from the Zwicky Transient Facility Machine learning methods are well established in the classification of quasars (QSOs). However, the advent of light curve observations adds a great amount of complexity to the problem. Our goal is to ...

5 million 😲 I'd imagine this will be massive for the Ellis-Baldwin test.
arxiv.org/abs/2502.13054
#cosmology

How’s this for a Monday morning? 🤩 A team of #HumansOfEuclid discovered an Einstein ring 💍 in nearby galaxy, NGC 6505. Only possible with the unique capabilities of this wonderful telescope!

It's stunningly close to a perfect ring as well. A nice little teaser before the Q1 data release next month. Gutted to be writing the thesis while all this data comes in 😅

DESI Strong Lens Foundry I: HST Observations and Modeling with GIGA-Lens We present the Dark Energy Spectroscopic Instrument (DESI) Strong Lens Foundry. We discovered $\sim 3500$ new strong gravitational lens candidates in the DESI Legacy Imaging Surveys using residual neu...

3,500 lenses is crazy. Will be very interested to know what proportion of these end up as spiral galaxy lenses?
arxiv.org/abs/2502.03455
#DESI #cosmology #strong-lensing