Australian Journal of Physics Astrophysical Supplement

Bolton, J. G.; Shimmins, AJ; Wall, J. V.

doi:10.1071/ph750239

Cited by 15 publications

(21 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has been suggested by Bridle and Feldman (1972) that steep-spectrum extended radio sources may be associated with X-ray emission as the result of inverse Compton scattering of the synchrotron electrons from the microwave background. No definite support for this suggestion could be found among the present results.…”

Section: Cluster Luminosity Functionmentioning

confidence: 99%

“…Although there is a diversity of absolute flux density scales at low frequencies, reasonably accurate spectral indices may be obtained by making systematic flux density adjustments. The data used are : 80 MHz, Higgins (1973, 1975); 85 MHz, Mills et al (1958);178 MHz, Goweret al (1967); 1420MHz, Ekers (1969, Murdoch (1976); 2700 MHz, Ekers (1969), Bolton et al (1975), Murdoch (1976, Wall et al (1971); 5000 MHz, Bolton et al (1975), Wall et al (1976). Flux density adjustment factors of 1· 2 and 1· 15 were applied to the 80 and 178 MHz data respectively.…”

Section: Cluster Luminosity Functionmentioning

confidence: 99%

See 1 more Smart Citation

A Radio Study of Abell Clusters

Mills¹,

Hoskins²

1977

Aust. J. Phys.

View full text Add to dashboard Cite

A search for radio sources close to 247 clusters of galaxies in the Abell catalogue has been carried out at the Molonglo Radio Observatory at a frequency of 408 MHz. A list of 116 sources near 89 clusters is given, identifications have been made and criteria for cluster membership have been established. A cluster luminosity function is derived in the range 1()23_10 25 WHz-l SCi, and spectra have been obtained for sources in 25 clusters utilizing published surveys made at other frequencies. It is found that there is no correlation between the richness of a cluster and its inclusion of at least one radio source, but those clusters containing multiple sources are significantly richer than average.

show abstract

Section: Cluster Luminosity Functionmentioning

confidence: 99%

Section: Cluster Luminosity Functionmentioning

confidence: 99%

A Radio Study of Abell Clusters

Mills¹,

Hoskins²

1977

Aust. J. Phys.

View full text Add to dashboard Cite

show abstract

“…These references have been taken from the MC1 list. Three of the sources are included in the Parkes 2700 MHz survey (Bolton et al 1975;Wall et al 1976) and are distinguished simply by the note PKS. Contour maps for some of the sources are given in Figs 1-18, and details of the maps are listed in Table 5.…”

Section: Source Cataloguementioning

confidence: 99%

The Molonglo Deep Sky Survey of Radio Sources. I. Declination Zone -20°

Robertson¹

1977

Aust. J. Phys.

View full text Add to dashboard Cite

Results of a deep survey made at 408 MHz with the Molonglo cross are given. The catalogue lists positions and flux densities for a total of 373 radio sources, most of which have not previously been catalogued, in a solid angle of 0·0201 Sf. This covers (with some excluded areas) right ascensions 0l h oom-06 h 44m and 13 h 45 m -17 h 19 m , with a range in declination of 41'. Eighteen contour maps are given of sources that are extended or have very close companions. A thorough error analysis is given, as well as new operational definitions of completeness and reliability. The lower limit of flux density is 88 mJy, which is five times the r.m.s. error. An upper limit of 1000 mJy has also been imposed. Typical errors in positions are 15" at 100 mJy and 6" at 250 mJy.

show abstract

“…First detected at radio frequencies (Bolton et al 1975), it was observed at X-rays by the Einstein observatory (Zamorani et al 1981) and later studied with ASCA (Cappi et al 1997;Siebert et al 1996), ROSAT (Fiore et al 1998), XMM (Reeves et al 2001) and Swift (Sambruna et al 2007). These observations showed an extremely luminous quasar (L x = 10 47 erg s −1 in the 0.1-2 keV range) with a particularly hard spectrum (Γ = 1 measured by Swift/BAT) and a weak iron K emission line and reflection features.…”

Section: Introductionmentioning

confidence: 99%

PKS 0537-286, carrying the information of the environment of SMBHs in the early Universe

Bottacini

Ajello

Greiner

et al. 2009

A&A

View full text Add to dashboard Cite

Context. The high-redshift (z = 3.1) blazar PKS 0537-286, belonging to the flat spectrum radio quasar blazar subclass, is one of the most luminous active galactic nuclei (AGN) in the Universe. Blazars are very suitable candidates for multiwavelength observations. Indeed, the relativistic beaming effect at work within the jet enhances their luminosity. This in turn allows the properties of the extragalactic jets, the powering central engine, and the surrounding environment to be derived. Aims. Our aim is to present the results of a multifrequency campaign from the near-IR to hard X-ray energies on PKS 0537-286 and give insight into the physical environment where the radiation processes take place. Methods. We observed the source at different epochs from 2006 to 2008 with INTEGRAL and Swift, and nearly simultaneously with ground-based optical telescopes. We also analyzed two archival spectra taken with XMM-Newton in 1999 and 2005. A comparative analysis of the results is performed. Results. The X-ray continuum of the blazar, as sampled by XMM, is described by a power law of index Γ = 1.2, modified by variable absorption at the soft X-rays, as found in other high-redshift QSOs. Modest X-ray continuum variability is found in the Swift observations. The combined Swift/BAT and Swift/XRT spectrum is very hard (Γ = 1.3). This, together with the non simultaneous EGRET detection and the more recent non detection by Fermi-LAT, constrains the peak of the high-energy component robustly. The optical/UV data, heavily affected by intervening Ly α absorption, indicate the presence of a bright thermal accretion disk that decreased in luminosity between 2006 and 2008. We infer from this a reduction of the BLR radius. When taking this into account, the 2006 and 2008 SEDs are compatible with a model based on synchrotron radiation and external inverse Compton scattering where the accretion-disk luminosity decreases between the 2 epochs by a factor 2, while the bulk Lorentz factor remains unchanged and the magnetic field changed only marginally.

show abstract

Australian Journal of Physics Astrophysical Supplement

Cited by 15 publications

References 0 publications

A Radio Study of Abell Clusters

A Radio Study of Abell Clusters

The Molonglo Deep Sky Survey of Radio Sources. I. Declination Zone -20°

PKS 0537-286, carrying the information of the environment of SMBHs in the early Universe

Contact Info

Product

Resources

About