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Dr John Helly's Outputs (8)

EIGER. VI. The Correlation Function, Host Halo Mass, and Duty Cycle of Luminous Quasars at z ≳ 6 (2024)
Journal Article
Eilers, A.-C., Mackenzie, R., Pizzati, E., Matthee, J., Hennawi, J. F., Zhang, H., Bordoloi, R., Kashino, D., Lilly, S. J., Naidu, R. P., Simcoe, R. A., Yue, M., Frenk, C. S., Helly, J. C., Schaller, M., & Schaye, J. (2024). EIGER. VI. The Correlation Function, Host Halo Mass, and Duty Cycle of Luminous Quasars at z ≳ 6. The Astrophysical Journal, 974(2), Article 275. https://doi.org/10.3847/1538-4357/ad778b

We expect luminous (M 1450 ≲ −26.5) high-redshift quasars to trace the highest-density peaks in the early Universe. Here, we present observations of four z ≳ 6 quasar fields using JWST/NIRCam in the imaging and wide-field slitless spectroscopy mode a... Read More about EIGER. VI. The Correlation Function, Host Halo Mass, and Duty Cycle of Luminous Quasars at z ≳ 6.

The FLAMINGO project: a comparison of galaxy cluster samples selected on mass, X-ray luminosity, Compton-Y parameter, or galaxy richness (2024)
Journal Article
Kugel, R., Schaye, J., Schaller, M., McCarthy, I. G., Braspenning, J., Helly, J. C., Forouhar Moreno, V. J., & McGibbon, R. J. (2024). The FLAMINGO project: a comparison of galaxy cluster samples selected on mass, X-ray luminosity, Compton-Y parameter, or galaxy richness. Monthly Notices of the Royal Astronomical Society, 534(3), 2378-2396. https://doi.org/10.1093/mnras/stae2218

Swift: A modern highly-parallel gravity and smoothed particle hydrodynamics solver for astrophysical and cosmological applications (2024)
Journal Article
Schaller, M., Borrow, J., Draper, P. W., Ivkovic, M., McAlpine, S., Vandenbroucke, B., Bahé, Y., Chaikin, E., Chalk, A. B. G., Chan, T. K., Correa, C., van Daalen, M., Elbers, W., Gonnet, P., Hausammann, L., Helly, J., Huško, F., Kegerreis, J. A., Nobels, F. S. J., Ploeckinger, S., …Xiang, Z. (2024). Swift: A modern highly-parallel gravity and smoothed particle hydrodynamics solver for astrophysical and cosmological applications. Monthly Notices of the Royal Astronomical Society, 530(2), 2378–2419. https://doi.org/10.1093/mnras/stae922

Numerical simulations have become one of the key tools used by theorists in all the fields of astrophysics and cosmology. The development of modern tools that target the largest existing computing systems and exploit state-of-the-art numerical method... Read More about Swift: A modern highly-parallel gravity and smoothed particle hydrodynamics solver for astrophysical and cosmological applications.

Non-linear CMB lensing with neutrinos and baryons: FLAMINGO simulations versus fast approximations (2024)
Journal Article
Upadhye, A., Kwan, J., McCarthy, I. G., Salcido, J., Helly, J. C., Kugel, R., …Broxterman, J. C. (2024). Non-linear CMB lensing with neutrinos and baryons: FLAMINGO simulations versus fast approximations. Monthly Notices of the Royal Astronomical Society, 529(2), 1862-1876. https://doi.org/10.1093/mnras/stae663

Weak lensing of the cosmic microwave background is rapidly emerging as a powerful probe of neutrinos, dark energy, and new
physics. We present a fast computation of the non-linear CMB lensing power spectrum that combines non-linear perturbation
the... Read More about Non-linear CMB lensing with neutrinos and baryons: FLAMINGO simulations versus fast approximations.

The FLAMINGO project: baryonic impact on weak gravitational lensing convergence peak counts (2024)
Journal Article
Broxterman, J. C., Schaller, M., Schaye, J., Hoekstra, H., Kuijken, K., Helly, J. C., Kugel, R., Braspenning, J., Elbers, W., Frenk, C. S., Kwan, J., McCarthy, I. G., Salcido, J., van Daalen, M. P., & Vandenbroucke, B. (2024). The FLAMINGO project: baryonic impact on weak gravitational lensing convergence peak counts. Monthly Notices of the Royal Astronomical Society, 529(3), 2309-2326. https://doi.org/10.1093/mnras/stae698

Weak gravitational lensing convergence peaks, the local maxima in weak lensing convergence maps, have been shown to contain valuable cosmological information complementary to commonly used two-point statistics. To exploit the full power of weak lensi... Read More about The FLAMINGO project: baryonic impact on weak gravitational lensing convergence peak counts.