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相关论文: Evaluation of the ALMA Prototype Antennas

200 篇论文

We demonstrate wide-angle, broadband and efficient reflection holography by utilizing coupled dipole-patch nano-antenna cells to impose an arbitrary phase profile on of the reflected light. High fidelity images were projected at angles of…

光学 · 物理学 2017-02-15 Yuval Yifat , Michal Eitan , Zeev Iluz , Yael Hanein , Amir Boag , Jacob Scheuer

We report the results of the Atacama Large Millimeter/sub-millimeter Array (ALMA) observations of the solar chromosphere on the southern polar limb. Coordinated observations with the Interface Region Imaging Spectrograph (IRIS) are also…

太阳与恒星天体物理 · 物理学 2018-08-22 Takaaki Yokoyama , Masumi Shimojo , Takenori J. Okamoto , Haruhisa Iijima

Modern interferometric imaging relies on advanced calibration that incorporates direction-dependent effects. Their increasing number of antennas (e.g. in LOFAR, VLA, MeerKAT/SKA) and sensitivity are often tempered with the accuracy of their…

天体物理仪器与方法 · 物理学 2019-03-20 K. Iheanetu , J. N. Girard , O. Smirnov , K. M. B. Asad , M. de Villiers , K. Thorat , S. Makhathini , R. A. Perley

We use the Atacama Large sub/Millimetre Array (ALMA) to efficiently observe spectral lines across Bands 3, 4, 5, 6, 7, and 8 at high-resolution (0.5" - 0.1") for 16 bright southern Herschel sources at $1.5 < z < 4.2$. With only six and a…

Movable antenna (MA), which can flexibly change the position of antenna in three-dimensional (3D) continuous space, is an emerging technology for achieving full spatial performance gains. In this paper, a prototype of MA communication…

信息论 · 计算机科学 2024-08-19 Zhenjun Dong , Zhiwen Zhou , Zhiqiang Xiao , Chaoyue Zhang , Xinrui Li , Hongqi Min , Yong Zeng , Shi Jin , Rui Zhang

Astrophysical tests of the stability of fundamental couplings are becoming an increasingly important probe of new physics. Motivated by the recent availability of new and stronger constraints we update previous works testing the consistency…

宇宙学与河外天体物理 · 物理学 2017-01-31 C. J. A. P. Martins , A. M. M. Pinho

After eight observing Cycles, the Atacama Large Millimeter-submillimeter Array (ALMA) is capable of observing in eight different bands (covering a frequency range from 84 to 950 GHz), with 66 antennas and two correlators. For the current…

天体物理仪器与方法 · 物理学 2021-01-12 Jorge F. García Yus , Bill Dent , Drew Brisbin , Chin-Shin Chang , Laura Gómez , Theodoros Nakos

Both the 1S-2S transition and the ground state hyperfine spectrum have been observed in trapped antihydrogen. The former constitutes the first observation of resonant interaction of light with an anti-atom, and the latter is the first…

原子物理 · 物理学 2018-03-28 S. Eriksson

Absorption-line systems detected in high resolution quasar spectra can be used to compare the value of dimensionless fundamental constants such as the fine-structure constant, alpha, and the proton-to-electron mass ratio, mu = m_p/m_e, as…

We present the first high-resolution, simultaneous observations of the solar chromosphere in the optical and millimeter wavelength ranges, obtained with ALMA and the IBIS instrument at the Dunn Solar Telescope. In this paper we concentrate…

太阳与恒星天体物理 · 物理学 2019-08-27 Momchil E. Molnar , Kevin P. Reardon , Yi Chai , Dale Gary , Han Uitenbroek , Gianna Cauzzi , Steven R. Cranmer

We conducted the observational tests of a phase correction scheme for the Atacama Compact Array (ACA) of the Atacama Large Millimeter and submillimeter Array (ALMA) using the Submillimeter Array (SMA). Interferometers at millimeter- and…

天体物理仪器与方法 · 物理学 2015-05-19 Satoki Matsushita , Yu-Lin Chen

The strongest known correspondence between ALMA 3mm emission and other solar observations is between the H-alpha line width and 3 mm brightness temperature, while the typical 3-5min p-mode oscillations found in many chromospheric…

太阳与恒星天体物理 · 物理学 2023-01-10 Lucas A. Tarr , Adam R. Kobelski , Sarah A. Jaeggli , Momchil Molnar , Gianna Cauzzi , Kevin P. Reardon

HH 211 is a highly collimated jet with a chain of knots and a wiggle structure on both sides of a young Class 0 protostar. We used two epochs of Atacama Large Millimeter/submillimeter Array (ALMA) data to study its inner jet in the…

太阳与恒星天体物理 · 物理学 2021-03-10 Kai-Syun Jhan , Chin-Fei Lee

The ALFA subdetector is designed to measure elastic proton-proton scattering from which the total cross section and $\rho$-parameter are determined. In 2016, special runs at a center-of-mass energy of $\sqrt{s} = 13$\,TeV and with…

高能物理 - 实验 · 物理学 2022-10-24 M. Schmidt

The sensitivity of ALMA makes it possible to detect thermal mm/submm emission from small/distant Solar System bodies at the sub-mJy level. Measured fluxes are primarily sensitive to the objects' diameters, but deriving precise sizes is…

地球与行星天体物理 · 物理学 2017-12-06 E. Lellouch , R. Moreno , T. Müller , S. Fornasier , P. Santos-Sanz , A. Moullet , M. Gurwell , J. Stansberry , R. Leiva , B. Sicardy , B. Butler , J. Boissier

The Advanced ACTPol upgrade on the Atacama Cosmology Telescope aims to improve the measurement of the cosmic microwave background anisotropies and polarization, using four new dichroic detector arrays fabricated on 150-mm silicon wafers.…

We test the consistency of several independent astrophysical measurements of fundamental dimensionless constants. In particular, we compare direct measurements of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio…

宇宙学与河外天体物理 · 物理学 2014-05-05 M. C. Ferreira , O. Frigola , C. J. A. P. Martins , A. M. R. V. L. Monteiro , J. Solà

We present new Atacama Large Millimeter/submillimeter Array (ALMA) continuum observations at 336GHz of two transition disks, SR21 and HD135344B. In combination with previous ALMA observations from Cycle 0 at 689GHz, we compare the…

The success of an astronomical facility is measured by its scientific impact. A principal metric for this impact is the ensemble of peer-reviewed publications based on the observational data obtained by the facility. We present a…

Instruments targeting 21~cm emission at high redshifts need a spectral dynamic range of better than ten thousand to distinguish the 21~cm background against bright foregrounds. Systematics arising from the antenna pattern are a leading…

天体物理仪器与方法 · 物理学 2026-05-21 Daniel C. Jacobs