相关论文: Evaluation of the ALMA Prototype Antennas

The design of an improved microstrip antenna operating in the 28 GHz frequency spectrum is the main goal of this work. The design used a Roger RT 5880 LZ substrate with a thickness and permittivity of 0.762mm and 1.96, respectively. The…

AMANDA is a high-energy neutrino telescope presently under construction at the geographical South Pole. In the Antarctic summer 1995/96, an array of 80 optical modules (OMs) arranged on 4 strings (AMANDA-B4) was deployed at depths between…

Measurements of the fine-structure constant alpha require methods from across subfields and are thus powerful tests of the consistency of theory and experiment in physics. Using the recoil frequency of cesium-133 atoms in a matter-wave…

We present initial results of very high resolution Atacama Large Millimeter/submillimeter Array (ALMA) observations of the $z$=3.042 gravitationally lensed galaxy HATLAS J090311.6+003906 (SDP.81). These observations were carried out using a…

A new method for examining the possible space-time variation of the fine structure constant ($\alpha$) is proposed. The technique uses a relatively simple measurement with an optical resonator to compare atom-stabilized optical frequency…

We present performance studies of the Time-of-Flight (ToF) subdetector of the ATLAS Forward Proton (AFP) detector at the LHC. Efficiencies and resolutions are measured using high-statistics data samples collected at low and moderate pile-up…

The KOALA experiment measures the differential cross section of (anti)proton-proton elastic scattering over a wide range of four-momentum transfer squared 0.0008 < |t| < 0.1 (GeV/c)$^2$ . The forward scattering parameters and the absolute…

Mitigating the far sidelobes of a wide field-of-view telescope is one of the critical issues for polarization observation of the cosmic microwave background. Since even small reflections of stray light at the millimeter-wave absorbers…

The ATLAS muon spectrometer is designed to measure muon momenta with a resolution of 4% @ 100 GeV/c rising to 10% @ 1 TeV/c track momentum. The spectrometer consists of precision tracking and trigger chambers embedded in a 2T magnetic field…

We report the ALMA observation of a $z\gtrsim10$ galaxy candidate (GHZ1) discovered from the GLASS-JWST Early Release Science Program. Our ALMA program aims to detect the [OIII] emission line at the rest-frame 3393.0062 GHz ($88.36\mu$m)…

This paper presents a reflectarray compact antenna test range (RACATR). The new range layout is designed to suppress the unwanted diffraction. A fast near field optimization method has been used to determine the phase distribution of the…

Aims. We use advanced 3D NLTE radiative magnetohydrodynamic simulations of the solar atmosphere to carry out detailed tests of chromospheric diagnostics at millimeter and submillimeter wavelengths. Methods. We focused on the diagnostics of…

Metasurfaces enable efficient manipulation of electromagnetic radiation. In particular, control over plane-wave reflection is one of the most useful features in many applications. Extensive research has been done in the field of anomalous…

We report the measurement results and compensation of the antenna elevation angle dependences of the Sub-millimeter Array (SMA) antenna characteristics. Without optimizing the subreflector (focus) positions as a function of the antenna…

Protoplanetary disks, which are the natural consequence of the gravitational collapse of the dense molecular cloud cores, host the formation of the known planetary systems in our universe. Substantial efforts have been dedicated to…

Recently, Adaptive Secondary Mirrors showed excellent on-sky results in the Near Infrared wavelengths. They currently provide 30mm inter-actuator spacing and about 1 kHz bandwidth. Pushing these devices to be operated at visible wavelengths…

At the present thesis a prototype antenna is studied. In chapter 1 the antenna's geometry is selected with the supervisor's assistance and its geometrical and dimensional characteristics are outlined. In chapter 2 an extensive theoretical…

The reliability of astronomical observations at millimeter and sub-millimeter wavelengths closely depends on a low vertical content of water vapor as well as on high atmospheric emission stability. Although Concordia station at Dome C…

By observing bright and compact astronomical sources while also taking data with the 183 GHz Water Vapour Radiometers, ALMA will be able to measure the `empirical' relationship between fluctuations in the phase of the astronomical signal…

This is the second article of a series devoted to European Extremely Large Telescope (E-ELT) site characterization. In this article we present the main properties of the parameters involved in high angular resolution observations from the…