We investigate reentrant and dielectric loaded cavities for the purpose of extending the range of axion cavity haloscopes to lower masses, below the range where the Axion Dark Matter experiment ...(ADMX) has already searched. Reentrant and dielectric loaded cavities were simulated numerically to calculate and optimize their form factors and quality factors. A prototype reentrant cavity was built and its measured properties were compared with the simulations. We estimate the sensitivity of axion dark matter searches using reentrant and dielectric loaded cavities inserted in the existing ADMX magnet at the University of Washington and a large magnet being installed at Fermilab.
The ADMX collaboration gathered data for its Run 1A axion dark matter search from January to June 2017, scanning with an axion haloscope over the frequency range 645-680 MHz (2.66-2.81 μeV in axion ...mass) at DFSZ sensitivity. The resulting axion search found no axion-like signals comprising all the dark matter in the form of a virialized galactic halo over the entire frequency range, implying lower bound exclusion limits at or below DFSZ coupling at the 90% confidence level. This paper presents expanded details of the axion search analysis of Run 1A, including review of relevant experimental systems, data-taking operations, preparation and interpretation of raw data, axion search methodology, candidate handling, and final axion limits.
We examined the incidence and association of bronchiolization of the alveoli with non‐small cell lung cancer in lung resection specimens from 2 patient groups: those with non‐small cell lung cancer ...and those diagnosed with a variety of non‐neoplastic lung conditions. We observed marked variation in bronchiolization of the alveoli morphology ranging from normal to severely atypical and developed a classification scheme based on growth pattern, cell number and cytologic criteria. Patterns of differentiation, proliferation and growth factor receptor and oncogene expression were studied using immuno‐histochemical and in situ hybridization techniques. While low‐grade (0–I) bronchiolization of the alveoli lesions demonstrated markers similar to normal bronchiolar epithelium, a significant decrease in the Clara cell 10 kDa protein and tubulin and an increase in surfactant protein‐A expression were observed in high‐grade (II–III) lesions. Focal p53 expression was detected in 2 high‐grade lesions, while c‐ myc mRNA and cJun protein were observed in all grades. No correlation was observed between bronchiolization of the alveoli incidence and histologic tumor type. A comparison of marker expression in lesions and tumors from the same case revealed a negative correlation between cytokeratin‐14 and c‐erbB‐2 immuno‐reactivity. Only one bronchialization of the alveoli lesion was found in the non‐neoplastic patient group. We conclude that up to 12% of non‐small cell lung cancer resection specimens contain bronchiolization of the alveoli lesions which exhibit altered morphology and patterns of differentiation. Int. J. Cancer 75:489–496, 1998. Published 1998 Wiley‐Liss, Inc.
We present the design, development, and field performance of an airborne mid-IR spectrometer configured for the simultaneous sensitive detection of CH 2 O (~40 pptv, 1 Hz) and C 2 H 6 (~15 pptv, 1 ...Hz).
Quantum cascade lasers (QCLs) are a relatively new type of semiconductor laser operating in the mid- to long-wave infrared. These monopolar multilayered quantum well structures can be fabricated to ...operate anywhere between 3.5 and 20
μm, which includes the molecular fingerprint region of the infrared. This makes them an ideal choice for infrared chemical sensing, a topic of great interest at present. Frequency stabilization and injection locking increase the utility of QCLs. We present results of locking QCLs to optical cavities, achieving relative linewidths down to 5.6
Hz. We report injection locking of one distributed feedback grating QCL with light from a similar QCL, demonstrating capture ranges of up to ±500
MHz, and suppression of amplitude modulation by up to 49
dB. We also present various cavity-enhanced chemical sensors employing the frequency stabilization techniques developed, including the resonant sideband technique known as NICE-OHMS. Sensitivities of 9.7×10
−11
cm
−1
Hz
−1/2 have been achieved in pure nitrous oxide.
Spontaneous celiac artery dissection caused by fibromuscular dysplasia is rare. Subsequent thrombosis and occlusion of the celiac trunk can result in intestinal ischemia and hepatic failure. We ...describe a case of spontaneous celiac artery dissection with an associated pseudoaneurysm caused by fibromuscular dysplasia, extending into the common hepatic artery. An endovascular intervention featuring robotic-assisted celiac artery cannulation with stent-assisted coil embolization resulted in successful treatment.
The Axion Dark Matter eXperiment (ADMX) has previously excluded Dine-Fischler-Srednicki-Zhitnisky (DFSZ) axions between 680-790 MHz under the assumption that the dark matter is described by the ...isothermal halo model. However, the precise nature of the velocity distribution of dark matter is still unknown, and alternative models have been proposed. We report the results of a non-virialized axion search over the mass range 2.81-3.31 {\mu}eV, corresponding to the frequency range 680-800 MHz. This analysis marks the most sensitive search for non-virialized axions sensitive to Doppler effects in the Milky Way Halo to date. Accounting for frequency shifts due to the detector's motion through the Galaxy, we exclude cold flow relic axions with a velocity dispersion of order 10^-7 c with 95% confidence.
We investigate reentrant and dielectric loaded cavities for the purpose of extending the range of axion cavity haloscopes to lower masses, below the range where the Axion Dark Matter eXperiment ...(ADMX) has already searched. Reentrant and dielectric loaded cavities were simulated numerically to calculate and optimize their form factors and quality factors. A prototype reentrant cavity was built and its measured properties were compared with the simulations. We estimate the sensitivity of axion dark matter searches using reentrant and dielectric loaded cavities inserted in the existing ADMX magnet at the University of Washington and a large magnet being installed at Fermilab.
We report the first result of a direct search for a Cosmic \({\it axion}\) Background (C\(a\)B) - a relativistic background of axions that is not dark matter - performed with the axion haloscope, the ...Axion Dark Matter eXperiment (ADMX). Conventional haloscope analyses search for a signal with a narrow bandwidth, as predicted for dark matter, whereas the C\(a\)B will be broad. We introduce a novel analysis strategy, which searches for a C\(a\)B induced daily modulation in the power measured by the haloscope. Using this, we repurpose data collected to search for dark matter to set a limit on the axion photon coupling of a C\(a\)B originating from dark matter cascade decay via a mediator in the 800-995 MHz frequency range. We find that the present sensitivity is limited by fluctuations in the cavity readout as the instrument scans across dark matter masses. Nevertheless, we suggest that these challenges can be surmounted using superconducting qubits as single photon counters, and allow ADMX to operate as a telescope searching for axions emerging from the decay of dark matter. The daily modulation analysis technique we introduce can be deployed for various broadband RF signals, such as other forms of a C\(a\)B or even high-frequency gravitational waves.
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