An Absolute Flux Density Measurement of the Supernova Remnant Cassiopeia A at 32 GHz
نویسندگان
چکیده
We report 32 GHz absolute flux density measurements of the supernova remnant Cas A, with an accuracy of 2.5%. The measurements were made with the 1.5-meter telescope at the Owens Valley Radio Observatory. The antenna gain had been measured by NIST in May 1990 to be 0.505 ± 0.007 Jy . Our observations of Cas A in May 1998 yield Scas,1998 = 194± 5 Jy. We also report absolute flux density measurements of 3C48, 3C147, 3C286, Jupiter, Saturn and Mars. Subject headings: standards — ISM: individual (Cassiopeia A) — planets and satellites: individual (Jupiter, Mars, Saturn) — quasars: individual (3C48, 3C147, 3C273, 3C286, 3C345) — galaxies: individual (3C84, 3C218, 3C353)
منابع مشابه
An Absolute Flux Density Measurement of the Supernova Remnant Casseopia A at 32 GHz
We report 32 GHz absolute flux density measurements of the supernova remnant Cas A, with an accuracy of 2.4%. The measurements were made with the 1.5-meter telescope at the Owens Valley Radio Observatory. The antenna gain had been measured by NIST in May 1990 to be 0.505 ± 0.007 Jy . Our observations of Cas A in May 1998 yield Scas,1998 = 194.0 ± 4.7 Jy. We also report absolute flux density mea...
متن کاملThe Fading of Supernova Remnant Cassiopeia A from 38 MHz to 16 . 5 GHz from 1949 to 1999 with New Observations at 1405 MHz
We report 1405 MHz measurements of the flux density of the ≈ 320 year old supernova remnant Cassiopeia A, relative to the flux density of Cygnus A, made between 1995 and 1999. When compared to measurements made between 1957 and 1976, we find that the rate at which Cassiopeia A has been fading at this and nearby frequencies has changed from ≈ 0.9 % yr in the 1960s to ≈ 0.6 − 0.7 % yr now. Furthe...
متن کاملA multiwavelength study of the remnant of nova GK Persei
We present new observations of the nebular remnant of the old nova GK Persei 1901, in the optical using the Himalayan Chandra Telescope (HCT) and at low radio frequencies using the Giant Metrewave Radio Telescope (GMRT). The previous such study was by Seaquist et al (1989, hereafter S89). The dimensions of the shell in the optical emission lines of [NII], [OIII] and [OII] are 108×94 arcsec, 104...
متن کاملObservation of VHE γ-rays from Cassiopeia A with the MAGIC telescope
Aims. We searched for very high energy (VHE) γ-ray emission from the supernova remnant Cassiopeia A Methods. The shell-type supernova remnant Cassiopeia A was observed with the 17 meter MAGIC telescope between July 2006 and January 2007 for a total time of 47 hours. Results. The source was detected above an energy of 250 GeV with a significance of 5.2 σ and a photon flux above 1 TeV of (7.3±0.7...
متن کاملDiscovery of the Energetic Pulsar J1747–2809 in the Supernova Remnant G0.9+0.1
The supernova remnant G0.9+0.1 has long been inferred to contain a central energetic pulsar. In observations with the NRAO Green Bank Telescope at 2 GHz, we have detected radio pulsations from PSR J1747–2809. The pulsar has a rotation period of 52 ms, and a spin-down luminosity of Ė = 4.3×1037 erg s−1, the second largest among known Galactic pulsars. With a dispersion measure of DM = 1133 pc cm...
متن کامل