A5016578459- Dark Matter and Cosmic Phenomena
- Gyrotron and Vacuum Electronics Research
- Particle physics theoretical and experimental studies
- Microwave Engineering and Waveguides
- Superconducting and THz Device Technology
- Particle Accelerators and Free-Electron Lasers
- Photonic and Optical Devices
- Particle accelerators and beam dynamics
- Atomic and Subatomic Physics Research
- Terahertz technology and applications
- Cosmology and Gravitation Theories
- Metamaterials and Metasurfaces Applications
- Vestibular and auditory disorders
- Quantum Information and Cryptography
- Pulsed Power Technology Applications
- Particle Detector Development and Performance
- Computational Physics and Python Applications
- Antenna Design and Analysis
- Optical Coatings and Gratings
- Astrophysics and Cosmic Phenomena
- Advanced Electron Microscopy Techniques and Applications
- Neuroscience and Neuropharmacology Research
- Neuroscience of respiration and sleep
- Laser-Matter Interactions and Applications
- Cold Atom Physics and Bose-Einstein Condensates
University of California, Berkeley
1992-2025
Fermi National Accelerator Laboratory
2022-2025
Wellesley College
2024-2025
SLAC National Accelerator Laboratory
2010-2024
Stanford University
2020-2024
University of Colorado Anschutz Medical Campus
2021
Yale University
2017
University of Colorado Denver
2017
Massachusetts Institute of Technology
2013-2016
Plasma Technology (United States)
2013-2014
We report on the first results from a new microwave cavity search for dark matter axions with masses above $20~\mu\text{eV}$. exclude axion models two-photon coupling $g_{a\gamma\gamma} \gtrsim 2\times10^{-14}~\text{GeV}^{-1}$ over range $23.55~\mu\text{eV} < m_a 24.0~\mu\text{eV}$. These represent two important achievements. First, we have reached cosmologically relevant sensitivity an order of magnitude higher in mass than any existing limits. Second, by incorporating dilution refrigerator...
We report on the results from a search for dark matter axions with HAYSTAC experiment using microwave cavity detector at frequencies between 5.6-5.8$\, \rm Ghz$. exclude axion models two photon coupling $g_{a\gamma\gamma}\,\gtrsim\,2\times10^{-14}\,\rm GeV^{-1}$, factor of 2.7 above benchmark KSVZ model over mass range 23.15$\,<\,$$m_a \,$<$\,$24.0$\,\mu\rm eV$. This doubles reported in our previous paper. achieve near-quantum-limited sensitivity by operating temperature $T<h\nu/2k_B$ and...
We introduce the Broadband Reflector Experiment for Axion Detection (BREAD) conceptual design and science program. This haloscope plans to search bosonic dark matter across [10^{-3},1] eV ([0.24, 240] THz) mass range. BREAD proposes a cylindrical metal barrel convert into photons, which novel parabolic reflector focuses onto photosensor. unique geometry enables enclosure in standard cryostats high-field solenoids, overcoming limitations of current dish antennas. A pilot 0.7 m^{2} experiment...
A search for dark matter axions with masses $>10\text{ }\text{ }\mathrm{\ensuremath{\mu}}\mathrm{eV}/{\mathrm{c}}^{2}$ has been performed using the HAYSTAC experiment's squeezed state receiver to achieve subquantum limited noise. This work includes details of design and operation experiment previously used in mass ranges 16.96--17.12 $17.14--17.28\text{ (4.100--4.140 GHz 4.145--4.178 GHz) as well upgrades facilitate an extended at higher masses. These include improvements data acquisition...
We report the experimental demonstration of a gyrotron traveling-wave-tube amplifier at 250 GHz that uses photonic band gap (PBG) interaction circuit. The achieved peak small signal gain 38 dB and 45 W output power 247.7 with an instantaneous $\ensuremath{-}3\text{ }\text{ }\mathrm{dB}$ bandwidth 0.4 GHz. can be tuned for operation from 245--256 widest 4.5 centered 253.25 was observed 24 dB. PBG circuit provides stability oscillations by supporting propagation transverse electric (TE) modes...
The cerebellum consists of parallel circuit modules that contribute to diverse behaviors, spanning motor cognitive. Recent work employing cell-type-specific tracing has identified circumscribed output channels the cerebellar nuclei (CbN) could confer tight functional specificity. These studies have largely focused on excitatory projections CbN, however, leaving open question whether inhibitory neurons also constitute multiple modules. We mapped and input patterns intersectionally restricted...
This Letter reports new results from the HAYSTAC experiment’s search for dark matter axions in our galactic halo. It represents widest to date that utilizes squeezing realize subquantum limited noise. The cover <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mn>1.71</a:mn><a:mtext> </a:mtext><a:mtext> </a:mtext><a:mi mathvariant="normal">μ</a:mi><a:mi>eV</a:mi></a:mrow></a:math> of newly scanned parameter space mass ranges <d:math...
In this paper, we present the design of a microwave generator using metamaterials (MTMs) in negative index waveguide interacting with high-power electron beam. The structure is formed by inserting two MTM plates loaded complementary split-ring-resonators (CSRRs) into rectangular waveguide. Electromagnetic simulations high-frequency simulator code confirm presence TM-like mode suitable for use backward-wave oscillator (BWO). Particle-in-cell (PIC) computer simulation technology (CST) Particle...
We report the experimental demonstration of a mm-wave electron accelerating structure powered by high-power rf source. demonstrate reliable coupling an unprecedented power—up to 575 kW into accelerator using quasi-optical setup. This standing wave consists single-cell copper cavity and Gaussian TM01 mode converter. The is 110 GHz, 10-ns long pulses. These pulses are chopped from 3 ms gyrotron oscillator laser-driven silicon switch. show high gradient up 230 MV/m that corresponds peak surface...
The last decade has seen unprecedented effort in dark matter model building at all mass scales coupled with the design of numerous new detection strategies. Transformative advances quantum technologies have led to a plethora high-precision sensors and strategies for ultralight ($<10\,$eV) bosonic that can be described by an oscillating classical, largely coherent field. This white paper focuses on searches wavelike scalar vector candidates.
Cryogenic calorimetric experiments to search for neutrinoless double-beta decay ( 0νββ ) are highly competitive, scalable and versatile in isotope. The largest planned detector array, CUPID, is comprised of about 1500 individual Li 2 100 MoO 4 modules with a further scale up envisioned follow experiment (CUPID-1T). In this article, we present novel concept targeting second stage low impedance TES based readout the absorber that easily mass-produced lends itself multiplexed readout. We design...
We present an experimental demonstration of ultrafast electron diffraction (UED) with THz-driven bunch compression and time-stamping that enables UED probes improved temporal resolution. Through longitudinal compression, a factor approximately four is achieved. Moreover, the time-of-arrival jitter between compressed pump laser pulse suppressed by three. Simultaneously, THz interaction imparts transverse spatiotemporal correlation on distribution, which we utilize to further enhance precision...
Understanding cerebellar contributions to motor coordination requires deeper insight into how the output structures of cerebellum, nuclei, integrate their inputs and influence downstream pathways. The magnocellular red nucleus (RNm), a brainstem premotor structure, is major target interposed (IN), has also been described in previous studies send feedback collaterals cerebellum. Because such pathway key position provide efferent information satisfying predictions about use corollary discharge...
Visualizing ultrafast dynamics at the atomic scale requires time-resolved characterization with femtosecond temporal resolution. For fully relativistic electron bunch probes, existing techniques for single-shot diffraction (UED) are limited by achievable probe length, charge, and timing jitter. We present first experimental demonstration of dual-fed THz-driven compression time-stamping that enables probes improved This technique utilizes two counter-propagating quasi-single-cycle THz pulses...
In experiments searching for axionic dark matter, the use of standard threshold-based data analysis discards valuable information. We present a Bayesian framework that builds on an existing processing protocol [B. M. Brubaker, L. Zhong, S. K. Lamoreaux, W. Lehnert, and A. van Bibber, Phys. Rev. D 96, 123008 (2017)] to extract more information from coherent axion detectors such as operating haloscopes. The avoids logical subtleties accompany enables greater experimental flexibility future...
Microcalorimeters that leverage microwave kinetic inductance detectors to read out phonon signals in the particle-absorbing target, referred as phonon-mediated (KIPM) detectors, offer an attractive detector architecture probe dark matter (DM) down fermionic thermal relic mass limit. A prototype KIPM featuring a single aluminum resonator patterned onto 1-gram silicon substrate was operated NEXUS low-background facility at Fermilab for characterization and evaluation of this architecture's...
We present results for the successful fabrication of low-loss THz metallic waveguide components using direct machining with a CNC end mill. The approach uses split-block process addition an RF choke running parallel to waveguide. greatly reduces coupling parasitic mode parallel-plate produced by split-block. This method has demonstrated loss as low 0.2 dB/cm at 280 GHz copper WR-3 It also been used in 3 and 10 dB directional couplers brass, demonstrating excellent agreement design...
We report the amplification of 250 GHz pulses as short 260 ps without observation pulse broadening using a photonic-band-gap circuit gyrotron traveling-wave-amplifier. The amplifier operates with device gain 38 dB and an instantaneous bandwidth 8 GHz. operational can be tuned over 16 by adjusting operating voltage electron beam magnetic field. uses 30 cm long interaction to confine desired TE03-like mode while suppressing lower order modes which result in undesired oscillations. is...
Abstract A plasma haloscope has recently been proposed as a feasible approach to extend the search for dark matter axions above 10 GHz (≈40 eV), whereby microwave cavity in conventional axion is supplanted by wire array metamaterial. Since frequency of metamaterial determined its unit cell, and thus bulk property, resonator any can be made arbitrarily large, contrast which incurs steep penalty volume with increasing frequency. To assess actual potential this concept practical haloscope,...
A gyrotron amplifier that uses a novel photonic band gap (PBG) interaction circuit has achieved peak small signal gain of 38 dB at 247.7 GHz, 32 kV and 0.35 A. The instantaneous -3 bandwidth the is 0.4 GHz. output power 45 W been measured. not saturated but limited by 7.5 mW available input power; believed to be order 500W. PBG confines TE03-like mode for operation provides stability from oscillations in lower modes. can tuned 245-255 Experimental results taken over wide range parameters,...