A5077669464- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astronomy and Astrophysical Research
- Geophysics and Gravity Measurements
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- GNSS positioning and interference
- Solar and Space Plasma Dynamics
- Cosmology and Gravitation Theories
- Pulsars and Gravitational Waves Research
- Particle Accelerators and Free-Electron Lasers
- Astrophysical Phenomena and Observations
- Ionosphere and magnetosphere dynamics
- Geomagnetism and Paleomagnetism Studies
- Superconducting and THz Device Technology
- Astro and Planetary Science
- Scientific Research and Discoveries
- Calibration and Measurement Techniques
- Dark Matter and Cosmic Phenomena
- Radio Wave Propagation Studies
- Historical Geography and Cartography
- History and Developments in Astronomy
Max Planck Institute for Radio Astronomy
2012-2024
Chinese Academy of Sciences
2021
Max Planck Society
1998-2019
Max Planck Institute for Research on Collective Goods
1987-1996
Max Planck Institute for Extraterrestrial Physics
1996
Understanding diffuse Galactic radio emission is interesting both in its own right and for minimizing foreground contamination of cosmological measurements. Cosmic Microwave Background experiments have focused on frequencies > 10 GHz, whereas 21 cm tomography the high redshift universe will mainly focus < 0.2 which less currently known about emission. Motivated by this, we present a global sky model derived from all publicly available total power large-area surveys, digitized with optical...
We present an improved Global Sky Model (GSM) of diffuse Galactic radio emission from 10 MHz to 5 THz, whose uses include foreground modelling for cosmic microwave background (CMB) and 21 cm cosmology. Our model improves on past work both algorithmically by adding new data sets such as the Planck maps enhanced Haslam map. method generalizes principal component analysis approach handle non-overlapping regions, enabling inclusion 29 sky with no region common all. also perform a blind...
The results of an absolutely calibrated radio continuum survey the South Celestial Hemisphere at a frequency 1420 MHz are presented. Contour maps show area for declination range to . steps (50 mK TB; 3 rms noise) and angular resolution (HPBW 35 4) match already existing Stockert northern sky same frequency. We compare flux densities compact extended sources with published data from Parkes 64-m telescope find excellent agreement in general. sensitive enough constrain synchrotron thermal...
We present the first section of a radio continuum and polarization survey at medium Galactic latitudes carried out with Effelsberg 100-m telescope 1.4 GHz. Four large fields have been observed, which all together cover an area about . The rms-sensitivity is 15 mK TB (about 7 mJy/beam area) in total intensity limited by confusion. A sensitivity 8 obtained linear polarization. angular resolution observations 9 l35. maps absolutely calibrated low data where ava ilable. Significant seen maps. In...
We present the results of a radio continuum survey at 21 cm wavelength Galactic plane between 955 240° and -4° ≤ b +5° with Effelsberg 100-m telescope. The data have been absolutely calibrated by using Stockert northern sky same wavelength. This complements for l Reich et al. (1990a). are presented as contour maps sensitivity 100 mK TB an angular resolution (HPBW) 94. In addition we extend list compact sources given (1990a) 1830 new entries. These peak flux densities exceeding 160 (or 79...
We study the spectral and polarization properties of supernova remnants (SNRs) based on our 6cm survey data. The observations were taken from Sino-German Galactic plane. By using integrated flux densities at together with measurements other wavelengths literature we derive global spectra 50 SNRs. In addition, use to present images 24 derived for 51 small SNRs angular sizes less than 1 degree. Global radio indices obtained in all cases except Cas A. For G15.1-1.6, G16.2-2.7, G16.4-0.5,...
Observations of large supernova remnants (SNRs) at high frequencies are rare, but provide valuable information about their physical properties. The total intensity and polarization properties 16 SNRs in the Galactic plane were investigated based on observations Urumqi $\lambda$6\ cm survey with an angular resolution 9$\farcm$5. We extracted linear maps from survey, obtained integrated flux densities, derived radio spectra context previously published densities various frequencies. In...
(Abridged) Polarization measurements of the Galactic plane at lambda6 cm probe interstellar medium (ISM) to larger distances compared longer wavelengths, hence enable us investigate properties magnetic fields and electron density. We are conducting a new continuum polarization survey covering 10degr < l 230degr |b|<5degr. Missing large-scale structures in U Q maps restored based on extrapolated K-band from WMAP satellite. The data analyzed together with other bands. discuss some...
<i>Context. <i/>Linearly polarized Galactic synchrotron emission provides valuable information about the properties of magnetic field and interstellar magneto-ionic medium, when Faraday rotation along line sight is properly taken into account.<i>Aims. <i/>We aim to survey plane at <i>λ<i/>6 cm including linear polarization. At such a short wavelength effects are in general small can be probed larger distances than long wavelengths.<i>Methods. <i/>The Urumqi 25-m telescope used for sensitive...
(Abridged) We have conducted a total intensity and polarization survey of the Galactic plane at 6 cm using Urumqi 25 m telescope for longitude range 10 deg<l<60 deg latitude |b|<5 deg. Missing absolute zero levels Stokes U Q maps were restored by extrapolating WMAP five-year K-band data. For intensities we recovered missing large-scale components referring to Effelsberg 11 survey. Total are presented with an angular resolution 9.5 arcmin sensitivity 1 mK 0.5 in polarized intensity,...
We present a survey of the 45 MHz radio continuum emission in declination range +5° to +65°. The observations were made with circular filled array Japanese Midle and Upper Atmosphere Radar half-power beam width . results are presented sets maps galactic equatorial coordinates (Epoch 1950).
Context. Linear polarization of Galactic synchrotron emission provides valuable information on the magnetic field and properties magneto-ionic medium. Polarized high-latitude is major foreground for studies cosmic microwave background.
Context: Observations of polarized emission are a significant source information on the magnetic field that pervades Interstellar Medium Galaxy. Despite acknowledged importance in interstellar processes, our knowledge configurations all scales is seriously limited. Aims: This paper describes an extensive survey Galactic at 1.4 GHz provides data with arcminute resolution and complete coverage structures from broadest angular to limit, giving magneto-ionic medium over wide range environments....
We aim to study the polarization and magnetic field properties of supernova remnant HB 9 using new 21-cm continuum cube data from Five-hundred-meter Aperture Spherical Radio Telescope (FAST). computed Faraday depth at 21 cm re-analyzed rotation measures (RMs) additional Effelsberg 2695-MHz Urumqi 4800-MHz data. FAST total-intensity images two subbands were decomposed into components multiple angular scales check spectral-index variation via temperature versus plots (TT-plots). The...
Radio continuum and polarization observations of the entire Cygnus Loop at λ6 cm wavelength were made with Urumqi 25 m telescope. The map is analysed together recently published maps from Effelsberg 100 telescope λ21 λ11 cm. integrated flux density 90 ± 9 Jy, which implies a spectral index 0.06. This rules out any global steepening up to However, small variations in some regions source are possible, but there no indications for curvature. linear data show percentage polarizations 35% areas...
Context. Galactic foreground emission fluctuations are a limiting factor for precise cosmic microwave background (CMB) anisotropy measurements.