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arXiv · 2210.09182

Weak lensing in the blue: a counter-intuitive strategy for stratospheric observations

Mohamed M. Shaaban·Ajay S. Gill·Jacqueline McCleary·Richard J. Massey·Steven J. Benton·Anthony M. Brown·Christopher J. Damaren·Tim Eifler·Aurelien A. Fraisse·Spencer Everett·Mathew N. Galloway·Michael Henderson·Bradley Holder·Eric M. Huff·Mathilde Jauzac·William C. Jones·David Lagattuta·Jason Leung·Lun Li·Thuy Vy T. Luu Johanna M. Nagy·C. Barth Netterfield·Susan F. Redmond·Jason D. Rhodes·Andrew Robertson·Jurgen Schmoll·Ellen Sirks·Suresh Sivanandam
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Abstract

The statistical power of weak lensing measurements is principally driven by the number of high redshift galaxies whose shapes are resolved. Conventional wisdom and physical intuition suggest this is optimised by deep imaging at long (red or near IR) wavelengths, to avoid losing redshifted Balmer break and Lyman break galaxies. We use the synthetic Emission Line EL-COSMOS catalogue to simulate lensing observations using different filters, from various altitudes. Here were predict the number of exposures to achieve a target z > 0.3 source density, using off-the-shelf and custom filters. Ground-based observations are easily better at red wavelengths, as (more narrowly) are space-based observations. However, we find that SuperBIT, a diffraction-limited observatory operating in the stratosphere, should instead perform its lensing-quality observations at blue wavelengths.

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Mohamed M. Shaaban, Ajay S. Gill, Jacqueline McCleary, Richard J. Massey, Steven J. Benton, Anthony M. Brown, Christopher J. Damaren, Tim Eifler, Aurelien A. Fraisse, Spencer Everett, Mathew N. Galloway, Michael Henderson, Bradley Holder, Eric M. Huff, Mathilde Jauzac, William C. Jones, David Lagattuta, Jason Leung, Lun Li, Thuy Vy T. Luu Johanna M. Nagy, C. Barth Netterfield, Susan F. Redmond, Jason D. Rhodes, Andrew Robertson, Jurgen Schmoll, Ellen Sirks, Suresh Sivanandam. 2022-10-17. Weak lensing in the blue: a counter-intuitive strategy for stratospheric observations. https://doi.org/10.3847/1538-3881%2Fac9b1c

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