Ultrastable frequency reference at 1.56 μm using a CO molecular overtone transition with the noise immune cavity-enhanced optical heterodyne molecular spectroscopy method

Kavli Affiliate: Robert Byer | First 5 Authors: Shailendar Saraf, Paul Berceau, Alberto Stochino, Robert Byer, John Lipa | Summary: We report on an ultrastable molecular clock based on the interrogation of the 3{nu} rotational-vibrational combination band at 1563nm of carbon monoxide 12C16O. The laser stabilization scheme is based on frequency modulation (FM) saturation spectroscopy […]


Continue.. Ultrastable frequency reference at 1.56 μm using a CO molecular overtone transition with the noise immune cavity-enhanced optical heterodyne molecular spectroscopy method

The design and performance of a prototype water Cherenkov optical time-projection chamber

Kavli Affiliate: Eric Oberla | First 5 Authors: E. Oberla, H. J. Frisch, , , | Summary: A first experimental test of tracking relativistic charged particles by `drifting’ Cherenkov photons in a water-based optical time-projection chamber (OTPC) has been performed at the Fermilab Test Beam Facility. The prototype OTPC detector consists of a 77~cm long, […]


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Preserving chemical signatures of primordial star formation in the first low-mass stars

Kavli Affiliate: Alexander Ji | First 5 Authors: Alexander P. Ji, Anna Frebel, Volker Bromm, , | Summary: We model early star forming regions and their chemical enrichment by Population III (Pop III) supernovae with nucleosynthetic yields featuring high [C/Fe] ratios and pair-instability supernova (PISN) signatures. We aim to test how well these chemical abundance […]


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Comprehensive Assessment of the Too-Big-to-Fail Problem

Fangzhou Jiang, Frank C. van den Bosch, , , | Summary: [[{“value”:”We use a semi-analytical model for the substructure of dark matter haloes to assess the too-big-to-fail (TBTF) problem. The model accurately reproduces the average subhalo mass and velocity functions, as well as their halo-to-halo variance, in N-body simulations. We construct thousands of realizations of […]


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The Effects of Self-Shadowing by a Puffed up Inner Rim in Scattered Light Images of Protoplanetary Disks

Kavli Affiliate: Ruobing Dong | First 5 Authors: Ruobing Dong, , , , | Summary: We explore whether protoplanetary disks with self-shadowing from puffed up inner rims exhibit observable features in scattered light images. We use both self-consistent hydrostatic equilibrium calculations and parameterized models to produce the vertically puffed up inner rims. We find that, […]


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Dispersion Distance and the Matter Distribution of the Universe in Dispersion Space

Kavli Affiliate: Kiyoshi Wesley Masui | First 5 Authors: Kiyoshi Wesley Masui, Kris Sigurdson, , , | Summary: We propose that "standard pings", brief broadband radio impulses, can be used to study the three-dimensional clustering of matter in the Universe even in the absence of redshift information. The dispersion of radio waves as they travel […]


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Beam calibration of radio telescopes with drones

Kavli Affiliate: Chihway Chang | First 5 Authors: Chihway Chang, Christian Monstein, Alexandre Refregier, Adam Amara, Adrian Glauser | Summary: We present a multi-frequency far-field beam map for the 5m dish telescope at the Bleien Observatory measured using a commercially available drone. We describe the hexacopter drone used in this experiment, the design of the […]


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