Published July 15, 1987 | Version v1
Journal article

X-ray intensity and spectral variations in the BL Lac sources H2155-304 and PKS0548-322

  • 1. Tata Inst. of Fundamental Research, Bombay (India)
  • 2. Jet Propulsion Lab., Pasadena, CA (USA)

Description

The results from the X-ray observations of two BL Lacertae objects, H2155-304 and PKS0548-322, are presented. The observations were carried out with the HEAO-1 A2 Low Energy Detectors, the High Resolution Imager and the Monitor Proportional Counter aboard the Einstein Observatory. Correlated X-ray intensity variations of approx. 20 per cent in the 0.15-3.5 keV energy band and approx. 40 per cent in the 1.5-10 keV energy band are observed in H2155-304 over a period of about 8 hr. A factor of 2 change in the intensity of PKS0548-322 in the 3.5-10 keV energy interval is also detected over a time interval of 1 hr. Variations in the X-ray intensity over a time-scale of months and the hardening of the spectrum with increasing intensity are seen in the HEAO-1 A2 data on H2155-304. (author)

Additional details

Publishing Information

Journal Title
Mon. Not. R. Astron. Soc.
Journal Volume
227
Journal Issue
2
Series
Mon. Not. R. Astron. Soc.
Journal Page Range
525-534
ISSN
0035-8711
CODEN
MNRAA

INIS

Country of Publication
United Kingdom
Country of Input or Organization
United Kingdom
INIS RN
18092123
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Resource subtype / Literary indicator
Numerical Data
Descriptors DEI
BL LACERTAE OBJECTS; COORDINATES; COSMIC X-RAY SOURCES; EXPERIMENTAL DATA; RADIATION FLUX; SOFT X RADIATION; VARIATIONS; X-RAY SPECTRA
Descriptors DEC
COSMIC RADIO SOURCES; COSMIC RAY SOURCES; DATA; ELECTROMAGNETIC RADIATION; INFORMATION; IONIZING RADIATIONS; NUMERICAL DATA; RADIATIONS; SPECTRA; X RADIATION