Simon Birrer
@sibirrer
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Wow, big congrats to TDCOSMO for their `Milestone’ paper: https://t.co/9q9KZETMwg . They analyze 8 strongly lensed quasars and find Hubble constant of 72+-3 km/s/Mpc with supernova prior on Omega_M, and H0=73+-3 with DESI BAO prior. This was one of the two local H0 studies from
arxiv.org
We present cosmological constraints from 8 strongly lensed quasars (hereafter, the TDCOSMO-2025 sample). Building on previous work, our analysis incorporated new deflector stellar velocity...
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Excited to share the latest work on measuring the Hubble constant by the TDCOSMO collaboration: https://t.co/f8SKmvvXzy This work was five years in the making by many excellent people
arxiv.org
We present cosmological constraints from 8 strongly lensed quasars (hereafter, the TDCOSMO-2025 sample). Building on previous work, our analysis incorporated new deflector stellar velocity...
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IT'S HAPPENING: Strongest EVER constraints on the free-streaming length of dark matter from a combination of the first 9 lenses in our @NASAWebb program and 5 previously measured lenses. This work was led by @ucmerced postdoc @RyanEKeeley
arxiv.org
This is the second in a series of papers in which we use JWST MIRI multiband imaging to measure the warm dust emission in a sample of 31 multiply imaged quasars, to be used as a probe of the...
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So excited about this paper! https://t.co/MrXhKmU6lh It's an idea we've had for years but implementing was very challenging. The brilliant @MrGilmanDa led this, with major innovations that will revolutionize our dark matter measurements. With @maverick_sh_oh and @sibirrer
arxiv.org
Strong gravitational lensing provides a purely gravitational means to infer properties of dark matter halos and thereby constrain the particle nature of dark matter. Strong lenses sometimes appear...
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Calling all citizen scientists! DES is looking for YOUR help to look at our images and find gravitational lenses! Anyone can participate in this limited-time scientific project, hosted by @the_zooniverse and @SpaceWarps . Start now at: https://t.co/4yOlM5G8Em
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Announcing the first paper from our JWST lensed quasar dark matter survey. TLDR: We are optimistic we will be able to to use the full survey to confirm the existence of completely dark, dark matter halos if they exist.
arxiv.org
The flux ratios of gravitationally lensed quasars provide a powerful probe of the nature of dark matter. Importantly, these ratios are sensitive to small-scale structure, irrespective of the...
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A new study published in @ScienceMagazine by researchers including Dept. of Physics & Astronomy Assistant Professor @sibirrer & Associate Professor Anja von der Linden uses supernova images to measure the expansion rate of the Universe. @sbuartssciences
news.stonybrook.edu
Stony Brook astrophysicists contribute to first-of-its-kind measurement STONY BROOK, NY, May 15, 2023 – A new technique to measure the expansion rate of the Universe may serve as a tool to help...
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Congratulations Victoria Grove, Grants Manager for the Department of Physics and Astronomy, on receiving a College of Arts and Sciences Staff Excellence award! #stonybrookuniversity #staff #excellence
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omg @Stanford already starting with blatant union-busting rhetoric: "Stanford’s relationship with our graduate students is, first and foremost, an educational one." babe no, grad students are *workers* whose labor props up the university, come on we've been through this
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What is the first thing you would do if you had a living wage? SBU and other (grad) workers reply here to answer!
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Bonus: We use raytracing in Lenstronomy to enhance the lensing scales of large-scale simulations. Starting with convergence computed on a coarse ~1' grid, we introduce finer fluctuations on galaxy lensing scales of ~1" to generate our training set.
github.com
Multi-purpose lens modeling software package. Contribute to lenstronomy/lenstronomy development by creating an account on GitHub.
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Paper alert🚨 Proteins are my new dark energy, but my latest paper employs hierarchical Bayesian inference, importance sampling, deep sets – all methods close to my heart! 🧵 https://t.co/hwvlBWZDed
arxiv.org
We present a Bayesian graph neural network (BGNN) that can estimate the weak lensing convergence ($κ$) from photometric measurements of galaxies along a given line of sight. The method is of...
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We are super excited to announce a mini lecture series on #JWST early science! How is this legendary telescope changing our understanding of first galaxies, cosmology, and exoplanets? Join us on Oct. 25 for the first talk in the series. 🌌 More info: https://t.co/5GXHDghMJz
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