Designation of the sources of x-rays

With the development of the observations in the field of the X-rays in Astronomy, a growing number of sources of x-rays could be detected. This number is today (2007) very high, but at the beginnings of the astronomy of x-rays, it was significantly weaker. Historically, these sources of x-rays were called name of the Constellation to which they belonged, followed capital letter X, of an indent, and their number of discovery. According to the cases, the Latin whole name of the constellation is indicated, or its abbreviation of three letters (Cyg X-1 or Cygnus X-1, for example). A similar designation is applied to the localized objects in an unquestionable way in other galaxies, in particular both Nuages of Magellan. This type of designation was used in particular at the time of the first satellite of observation of x-rays, Uhuru.

Among the sources of x-rays histories the most known, one finds:

Centaurus X-1, a Remanent of supernova, associated with the historical Supernova SN 185
Centaurus X-3, the first Pulsar X, pertaining to a Binary system and accrétant of the matter resulting from his/her companion, called star of Krzeminski;
Cygnus X-1, the first stellar candidate Black hole the, and still most serious to date;
Cygnus X-3, a Microquasar
Herculis X-1, another pulsar X of the same type as Cen X-3;
Sagittarius X-4, the Binary system with shortest the orbital Period known (less than 12 minutes);
Scorpius X-1, source presenting of the Oscillations quasi-periodicals;
Taurus X-1 for the Remanent of supernova of the historical Supernova SN 1054, (the Nebulous of the Crab).

The astronomical sources of x-rays being almost exclusively detected by satellite , whose resolution remained vague a long time, they are in general located by a symbol indicating the name of the satellite, follow-up of the coordinates (sometimes approximate) of the source.

One finds thus the denominations following:

2A HHMM+DD or 2A HHMM+DDd , then 3A HHMM+DDd : sources detected by the satellite Ariel V (105 then 251 in all), located by their position in Right ascension (hours and minutes) and variation (degree and tenth of degree)
1ES HHMM+DD.dA : sources detected by the satellite Einstein (or HEAO-2), 821; the positions are expressed in hour and minutes of right ascension and degree and tenth of degree in variation;
2nd NNNN or 2nd HHMM.m+DDMM for the second grinding of the data of the Einstein satellite, counting 9612 sources, located by their number or their coordinates in hour, minute and tenth of minutes in right ascension and degree and minutes in variation;
1:00 HHMM+DDd : sources detected by the satellite HEAO-1 (251 in all), located by their position in right ascension (hours and minutes) and variation (degree and tenth of degree);
H HHMM+DDd : sources detected by another instrument of the satellite HEAO-1 (174 in all), located by their position in right ascension (hours and minutes) and variation (degree and tenth of degree);
INTEGRAL1 NNN , for the first sources (123 in all) detected by the INTEGRAL satellite in 2004;
MXB HHMM+DD or MXB HHMM+DDd for a catalog of sources of the type Sursauteur X, carried out initially in 1981 by Walter H.G. Lewin and Paul C. Joss, acronym MXB corresponding to Massachusetts university X-ray Bursters ;
1RXS JHHMMSS.s+DDMMSS for the first reading taken by the satellite Rose (more 120 000 objects); the positions are given in hour, minute, second and tenth of a second in right ascension and degree, minute, second in variation, the J meaning that the time corresponds to J2000.0;
X-ray JHHMM.m+DDMM , JHHMMSS+DDMMm gold X-ray JHHMMSS.s+DDMMS for sources observed by Rose, the format determining the precision of localization of the source;
2U HHMM+DD , 3U HHMM+DD , and 4U HHMM+DD or 4U HHMM+DDd for the sources detected by the satellite Uhuru in 1972 (125, then 161, and finally 339 for the three statements), with position expressed in hour and minute of right ascension and degree of variation, except for last grinding, where the tenth of degree of variation are known.

See too

Designation of the sources of waves radio

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