We present cosmological constraints from a gravitational lensing mass map covering 9400 deg2reconstructed from measurements of the cosmic microwave background (CMB) made by the Atacama Cosmology Telescope (ACT) from 2017 to 2021. In combination with measurements of baryon acoustic oscillations and big bang nucleosynthesis, we obtain the clustering amplitude
The explicit breaking of the axial symmetry by quantum fluctuations gives rise to the so-called axial anomaly. This phenomenon is solely responsible for the decay of the neutral pion π0into two photons (γγ), leading to its unusually short lifetime. We precisely measured the decay width Γ of the
- Award ID(s):
- 1812396
- NSF-PAR ID:
- 10147467
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 368
- Issue:
- 6490
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- p. 506-509
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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